THE GAS ENGINEER'S POCKET-BOOK
THE
GAS ENGINEER'S
POCKET-BOOK
COMPRISING RELATING TO
THE MANUFACTURE, DISTRIBUTION, AND USE OF COAL GAS
AND
THE CONSTRUCTION OF GAS WORKS
BY
HENRY O'CONNOR
ASSOCIATE MEMBER OF THE INSTITUTION OF CIVIL ENGINEERS PAST PRESIDENT OF THE SOCIETY OF ENGINEERS
SECOND EDITION, REVISED
LONDON CROSBY LOCKWOOD AND SON
7, STATIONERS' HALL COURT, LUDGATE HILL 1901
BRADBURY, AGNEW, & CO. LD., PRINTERS, LONDON AND XONBRIDGE.
vv
getricateft
TO HIS OLD CHIEFS
GOBBET WOODALL, ESQ., M.lNST.C.E.
GEORGE LIVESEY, ESQ., M.lNST.C.E.
GEORGE CARELESS TREWBY, ESQ., M.lNST.C.E.
IN ACKNOWLEDGMENT OF MUCH VALUABLE INFORMATION EECEIVED
FROM THEM BY THE AUTHOR DURING HIS WORK
UNDER THEIR DIRECTION
HENRY O'CONNOR
95908
PEEFACE.
IN placing this compilation before his readers — and in particular, his brother Engineers of the Gas Industry — it may not be out of place for the Author to indicate the circumstances which have led, in the first instance, to the preparation of the Tables, Notes, and other matter comprised in the volume, and now to their issue in the present form.
Having frequently during the course of his professional career experienced the want of any book containing those numerous tables, data, &c., which, with the spread of engineering knowledge, are every day becoming more and more necessary to the Gas Engineer for reference, he has for many years been in the habit of making and preserving, for his own use, full notes from every available source. These notes have formed the basis of the present work, and the fact that they were originally intended only for his own personal use has rendered it in many cases well-nigh impossible for the Author to acknowledge the sources of his information. He desires, however, to express here his indebtedness to both the Journal of Gas Lighting and the Gas World, whose full and careful reports, given from time to time, of papers read and discussions held at the various meetings of Engineering Societies, at which questions con- cerning the Gas Industry have been under review, have afforded him the means of obtaining a considerable portion of the matter here presented.
Vlll PREFACE.
In deciding the plan upon which the matter should be arranged, it appeared to the Author that the most suitable method was to take the various processes consecutively as they occur in the course of Gas-making, and to treat of the Construction of the Works separately from the Manufacture of the Gas.
The diagrammatic form of tabulating has been followed wherever it seemed to be preferable, and the dimensions of the volume have in consequence been increased from the ordinary pocket-book size, so as to enable the diagrams to be better seen and read.
The Tables have been most carefully checked, and every precaution taken to render them as accurate as possible. Should, however, any error be detected in them, the Author will feel much obliged for information of the fact ; while he will welcome any communication upon the subject generally with which readers may be pleased to favour him.
H. O'C.
Edinburgh, 1897.
NOTE TO SECOND EDITION.
IT is very gratifying that a new edition has been speedily called for, and the opportunity has been taken of correcting a few errors of the press. The Statutory Regulations for Testing the Illuminating Power and Purity of Gas have also been added, and the text of the book amended where it was found advisable.
TABLE OF CONTENTS.
GENERAL CONSTRUCTING MEMORANDA. General Mathematical Tables.
PAGE
Squares, Cubes, Square Roots, Cube Eoots, Reciprocals and
Logarithms 1
Logarithms, description of 23
Area and Circumferences of Circles in Jths, ±\jths, and ^ths . 21
Properties of Circles 41
Weights and Measures 42
Decimals of £1, cwt., mile, year, inch, foot, lb., ton . . . 45
Equivalent English and Metric Weights and Measures . . 56
Cubic Feet into Cubic Metres, and the reverse . . . . 58
Sizes of Drawing Paper, and Colours used in Drawings . . 59
Weights of Materials 60
Foundations . . . . 64
Footings 65
Damp Courses and Inverted Arches 66
Brickwork notes . . . 67
„ Courses (diagrams) ....... 70
Scaffolding notes 72
Strength of Mortar 72
Portland Cement notes . ........ 73
Facing and Pointing . . . . . . .74
Resistance to Crushing . 75
Stonework notes . . . . . . . . . .76
Painting notes 76
Glazing notes 77
Roof Coverings 78
Proportions of Treads and Risers to Staircases . . -. . 81
X CONTENTS.
PAGE
Timber notes 81
Breaking Loads on Wooden Pillars (diagram) .... 84
Safe Loads on Wooden Beams ., .... 85
„ „ Joists „ .... 86
Dead and Live Loads 87
Water Power, Specific Heats 88
Radiant Heat . . 89
Factors of Safety . 89
Weight of Flat Rolled Iron 90
Birmingham and American Gauges 96
Weight of Zinc, Thickness of Tin- Plates 96
Corrugated Iron 97
Heat Conductivity of Metals 97
Castings 99
Case-Hardening 100
Breaking Strength, Elastic Strength, and Modulus of Elasticity 101
Proportions, Strengths, and Weights of Bolts, Nuts, and Washers 102
„ and Strengths of Riveted Joints . . . .104
„ Strengths, and Weights of Rivets . ... 106
Strengths of Ropes and Chains 109
Testing Iron and Steel 113
Weights of Cast Iron Pipes 115
Average Dimensions of Socket Connections 116
„ ,, Flanged „ .... 118
Diagrams of Weight of Cast Iron Pipes 120
Proportions of Pipe Flanges 122
Weight of Lead and Composition Pipes . . . . '. 123
Whit worth Screw Threads 125
Weights of Sheet Metals (diagram) 128
Weight of Half-round Iron and Sheet Brass . . . .130
Wrought Iron Pipe Thicknesses 131
Wrought Iron Girders notes 132
Diagram of proper Size of Rolled Joists 134
Moments of Inertia and Resistance of Beams .... 13(5
Girders 138
Plates 140
Least Radius of Gyration 141
Arches 143
Unloading Materials and Storage (Construction).
Space required by different Coals 145
Coal Stores . 145
CONTENTS. XI
PAGE
Stabling and Roads . . . 146
Railways and Locomotives . 148
Crane Hooks . 150
Retort House (Construction).
Hydraulic Cranes . • - 151
Conveyors and Grabs 152
Fire-Clays and Bricks ' . . . . 152
Retorts 153
Dimensions of Retort Houses 154
Settings 155
Hydraulic Mains . 159
Ascension Pipes 160
Hydraulic Main Valves 161
Connections in Gas Works 162
Condensers (Construction).
Dimensions necessary 163
General notes 163
Loss of Heat in Air and under Water 164
Deposition of Tar . ... 165
Tar and Liquor Tanks 165
Boilers, Engines, Pumps, and Exhausters (Construction).
Horse-power and Space required . . . . . 166
„ „ for 24-inch Pressure 1G7
., ., to pass Gas . . . . . . . 167
Steam Pressures 169
Proportions of Boilers 170
Strength „ 171
Safety Valves 176
Boiler Chimneys 176
Lightning Conductors . . . • 181
Steam and Exhaust Pipes 182
Distance between Bearings of Shafts (diagram) . . . . 183
Notes on Pumps 184
Flywheels and Toothed Gearing 187
Belt Gearing 188
Xll CONTENTS.
PAGE
Rope Gearing 189
Gas Engines 190
Values of Explosive Mixtures . . . . . . 193
Scrubbers and Washers (Construction).
Dimensions necessary 195
Absorptive Power of Water 196
Reaction of Cyanides 196
Purifiers (Construction).
Area required '..197
Arrangements of Purifier Connections . . . .199
Claus Process . . . 201
Gasholder Tanks (Construction).
General notes and Natural Slopes of Earths .... 202
Resistance of Earth Backing 204
Formula for Strength of Tank Walls .205
Pressure of Water against a Tank Side . • 206
Thickness of Sheets for Wrought Iron Tanks (diagram) . . 208
Concrete Tank Walls . . . 209
Gasholders (Construction).
General notes . . . 210
Strains on Top Sheets . . 211
Rivets required for different Thicknesses of Plates . . . 212
Force of the Wind 215
Allowance for Wind and Snow 217
Guide Framing notes . . 220
Diagram of Pressures thrown by Holders 221
Formulas for Multipost Gasholders 222
„ Cantilever „ 223
Notes on Cups and Grips . . 221
Strains on Gasholder Sheeting . . . . . . . 225
Workshop Notes.
Station Meters 229
r, ., General Dimensions . , 230
CONTENTS. Xlll
MANUFACTURING. Storing Materials.
PAGE
Stacking Coal 231
Igniting Point of various Coals 232
Retort House (Working)
Carbonising notes . . . . . ... . . 233
Effects of Temperature on Distillation 235
Make of Gas per Hour 237
Climatic Effects on Carbonisation . 239
Generator Furnaces . . . 240
Kegenerator Furnaces . 241
Labour required for Carbonising 245
Curing Stopped Ascension Pipes . . . . . . 246
Table of Effects of Heat . . 247
Pyrometers 249
Residuals from Coal 251
Gas from different Substances . 253
Condensing Gas.
General notes '•.••. . . . 255
Tests for Napthalene . . .256
Exhausters, &c.
Effects of Air on Gas 258
Combustion of Fuels in Boilers . , 259
Boiler Incrustations , 261
Washing and Scrubbing.
Quantity of Ammonia removed 262
General notes 263
Cyanogen 265
XIV CONTENTS.
Purification.
PAGE
Analyses of Oxides 267
Notes on Oxide Purification 269
„ Lime „ 270
Removal of Sulphur Compounds . . . . . . 272
„ Carbon Dioxide . 272
Weldon Mud 274
Revivification in situ 275
Oxygen in Purification . . . . . . . . 276
Arresting Cyanogen Compounds 277
Composition of Purified Illuminating Gas ... . . 277
Gasholders (Care of).
Diffusion of Gases 279
Painting notes 279
Distributing Gas.
Flow of Gases through Pipes 281
Diagrams of Distributing Power of Pipes 282
Lead required for Jointing 285
Dimensions of Pipes 286
Jointing Material . . . 288
Dimensions of Socket Joints 289
Testing Mains 291
Rack and Pinion Valves 293
Service Pipes 296
Wrought Iron Tubing 297
Diagram of Comparative Pressures 299
Napthalene 301
Cold Enrichers 301
Diagram of the Number of Cubic Feet per 1^7. for different
prices per 1,000 Cubic Feet 303
Diagram of Comparison of Prices of Gas in Sterling and French
Moneys 304
Relative Values of Illuminating Agents 305
Vitiation of Air 307
Height of Lamps . 309
CONTENTS. XV
PAGE
Ventilation notes 311
Comparative Costs of different Lights 313
Gas Stove notes 314
Warming by Steam 315
Heats of Fires 317
Balloons 318
Wet Meters . . 319
Dry Meters 320
Testing.
Elementary Bodies 322
Air, Gas, and Water 323
Saturated Hydrocarbons 325
Tension of Aqueous Vapour 327
Explosive Mixtures . . 329
Lbs. Water heated and C02 produced 331
Expansion and Weight of Water 333
Melting Points . . . 334
Boiling Points 335
Specific Heats 336
Freezing Mixtures 337
Radiation of Heat 339
Heat Units evolved by different Substances 341
To Prepare Chemical Indicators 342
„ Normal Solutions - . 344
Twaddell 346
Burners 348
Composition of Coal Gas 349
Comparative Analysis of Coal and Carburetted Water Gas . . 352
Values of Illuminating Gases 353
Illuminating Values of Hydrocarbons 355
Temperatures of Flames . . 357
Photometers 358
„ general notes 360
Diagram for Correcting for Irregular Burning of Candles . . 362
„ „ Gas. . . 364
„ of Tabular Numbers 366
„ for Correcting for Tabular Numbers .... 368
Harcourt's 1 -Candle Pen tane Unit 369
Hefner Unit , 370
XVI CONTENTS.
PAGE
Dibdin's 10- Candle Unit . . . 371
To Test Lime 372
„ Oxide . . . . . . . . . . . 373
Ten per cent. Acid Solution 375
Diagram for use with Harcourt's Colour Test . . . . 377
Specific Gravities of Gases . . .879
Testing Coals . . . 380
Diagrams showing actual Grains Sulphur from Grains BaS04 . 383
Enriching Processes.
Cost of Enrichment . . . 385
Benzol as an Enricher , . . . . 387
Acetylene . . . . . . ... . . . 390
Carburetted Water Gas Plant 393
Calorific Value of Water Gas 399
Dowson Gas . . . 400
Peebles Process 402
Products Works.
Sulphate Making .' . . 404
Coal Tar Products . . . . - . .• . .406 Analysis of Coal Tar 408
Supplementary.
Statutory and Official Regulations for Testing the Illuminating
Power and Purity of Gas . . 410
Gas Referees' Standard Burner 422
Ten-Candle Pentane Lamp . . . • • • • • 423
The Table Photometer 425
Table giving Illuminating Power of Gas 426
English, French, and German Glossary of Terms used in Gas
Works, , . ' 427
THE
GAS ENGINEER'S
POCKET-BOOK.
GENEKAL MATHEMATICAL TABLES.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
1 |
1 |
1 |
1-000 |
1-000 |
1-000000 |
000000 |
301030 |
|
2 |
4 |
8 |
1-414 |
1-259 |
•500000 |
301030 |
176091 |
|
3 |
9 |
27 |
1-732 |
1-442 |
•333333 |
477121 |
124939 |
|
4 |
16 |
64 |
2-000 |
1-587 |
•250000 |
602060 |
96910 |
|
5 |
25 |
125 |
2-236 |
1-709 |
•200000 |
698970 |
79181 |
|
6 |
36 |
216 |
2-449 |
1-817 |
•166667 |
778151 |
66947 |
|
7 |
49 |
343 |
2-645 |
1-912 |
•142857 |
845098 |
57992 |
|
8 |
64 |
512 |
2-828 |
2-000 |
•125000 |
903090 |
51153 |
|
9 |
81 |
729 |
3-000 |
2-080 |
•111111 |
954243 |
45757 |
|
10 |
100 |
1.000 |
3-162 |
2-154 |
•100000 |
000000 |
41393 |
|
11 |
121 |
1,331 |
3-316 |
2-223 |
•090909 |
041393 |
37788 |
|
12 |
144 |
1,728 |
3-464 |
2-289 |
•083333 |
079181 |
34762 |
|
13 |
169 |
2,197 |
3-605 |
2-351 |
•076923 |
113943 |
32185 |
|
14 |
196 |
2,744 |
3-741 |
2-410 |
•071429 |
146128 |
29963 |
|
15 |
225 |
3,375 |
3-872 |
2-466 |
•066667 |
176091 |
28029 |
|
16 |
256 |
4,096 |
4-000 |
2-519 |
•062500 |
204120 |
26329 |
|
17 |
289 |
4,913 |
4-123 |
2-571 |
•058824 |
230449 |
24824 |
|
18 |
324 |
5,832 |
4-242 |
2-620 1 -055556 |
255273 |
23481 |
|
|
19 |
361 |
6,859 |
4-358 |
2-668 |
•052632 |
278754 |
22276 |
|
20 |
400 |
8,000 |
4-472 |
2-714 |
•050000 |
301030 |
21189 |
|
21 |
441 |
9,261 |
4-582 |
2-758 |
•047619 |
322219 |
20204 |
|
22 |
484 |
10,624 |
4-690 |
2-802 |
•015455 |
342423 |
19305 |
|
23 |
529 |
12,167 |
4-795 |
2-843 |
•043478 |
361728 |
18483 |
|
24 |
576 |
13,824 |
4-898 |
2-884 |
•041667 |
380211 |
17729 |
|
25 |
625 |
15,625 |
5-000 |
2-924 |
•040000 |
397940 |
17033 |
|
26 |
676 |
17,576 |
5-099 |
2-962 |
•038462 |
414973 |
16391 |
|
27 |
729 |
19,683 « |
5-196 |
3-000 |
•037037 |
431364 |
15794 |
|
28 |
784 |
21.952 |
5-291 |
3-036 |
•035714 |
447158 |
15240 |
|
29 |
841 |
24,389 |
5-385 |
3-072 |
•034483 |
462398 |
14723 |
G.E.
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
«"* s= |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
|
30 |
900 |
27,000 |
5-477 |
3-107 |
•033333 477121 |
14241 |
|
|
31 |
961 |
29,791 |
5-567 |
3-141 |
•032258 491362 |
13798 |
|
|
32 |
1.024 |
32,768 |
5-656 |
3-175 |
•031250 505150 |
13364 |
|
|
33 |
1,089 |
35,937 |
5-744 |
3-207 |
•030303 518514 |
12965 |
|
|
34 |
1,156 |
39,304 |
5-830 |
3-239 |
•029412 531479 |
125S9 |
|
|
35 |
1^225 |
42,875 |
5-916 |
3-271 |
•028571 |544068 |
12235 |
|
|
36 |
1,296 |
46,656 |
6-000 |
3-301 |
•027778 556303 11899 |
||
|
37 |
1,369 |
50.653 |
6-082 |
3-332 |
•027027 568202 11582 |
||
|
38 |
1,444 |
54,872 |
6-164 |
3-361 |
•026316 ; 579784 |
11281 |
|
|
39 |
1,521 |
59,319 |
6-244 |
3-391 |
•025641 |
591065 |
10995 |
|
40 |
1,600 |
64,000 |
6-326 |
3-419 |
•025000 |
602060 |
10724 |
|
41 |
1,681 |
68,921 |
6-403 |
3-448 |
•024390 |
612784 |
10465 |
|
42 |
1,764 |
74,088 |
6-480 |
3-476 |
•023810 |
623249 |
10219 |
|
43 |
1.849 |
79,507 |
6-557 3-503 |
•023256 |
633468 |
9985 |
|
|
44 |
1,986 |
85,184 |
6-633 3-530 |
•022727 |
643453 |
9760 |
|
|
45 |
2,025 |
91,125 |
6-708 |
3-556 |
•022222 |
653213 |
9545 |
|
46 |
2,116 |
97,336 |
6-782 |
3-583 |
•021739 |
662758 |
9340 |
|
47 |
2,209 |
103,823 |
6-855 |
3-608 |
•021277 |
672098 |
9143 |
|
48 |
2,304 |
110,592 |
6-928 |
3-634 |
•020833 |
681241 |
8955 |
|
49 |
2,401 |
117,649 |
7-000 |
3-659 |
•020408 |
690196 |
8774 |
|
50 |
2,500 |
125,000 |
7-071 |
3-684 |
•020000 |
698970 |
8600 |
|
51 |
2,601 |
132,651 |
7-141 |
3-708 |
•019608 |
707570 |
8433 |
|
52 |
2,704 |
140,608 |
7-211 |
3-732 |
•019231 |
716003 |
8273 |
|
53 |
2,809 |
148,877 |
7-280 |
3-756 |
•018868 |
724276 |
8118 |
|
54 |
2,916 |
157,464 |
7-348 |
3-779 |
•018519 |
732394 |
7969 |
|
55 |
3,025 |
166,375 |
7-416 |
3-802 |
•018182 |
740363 |
7825 |
|
56 |
3,136 |
175,616 |
7-483 |
3-825 |
•017857 |
748188 |
7687 |
|
57 |
3,249 |
185,193 |
7-549 |
3-848 |
•017544 |
755875 |
7553 |
|
58 |
3,364 |
195,122 |
7-615 |
3-870 |
•017241 |
763428 |
7424 |
|
59 |
3,481 |
205,379 |
7-681 |
3-892 |
•016949 |
770852 |
7299 |
|
60 |
3,600 |
216,000 |
7-745 |
3-914 |
•016667 |
778151 |
7179 |
|
61 |
3,721 |
226,981 |
7-810 |
3-936 |
•016393 785330 |
7062 |
|
|
62 |
3,844 |
238,328 |
7-874 |
3-957 |
•016129 792392 |
6949 |
|
|
63 |
3,969 |
250,047 |
7-937 |
3-979 |
•015873 799341 |
6839 |
|
|
64 |
4,096 |
262,144 |
8-000 |
4-000 |
•015625 J806180 |
6733 |
|
|
65 |
4.225 |
274,625 |
8-062 |
4-020 |
•015385 812918 |
6631 |
|
|
66 |
4,356 |
287,496 |
8-124 |
4-041 |
•015152 819544 |
6531 |
|
|
67 |
4,489 |
300,763 |
8-185 |
4-061 |
•014925 826075 |
6434 |
|
|
68 |
4,624 |
314,432 |
8-246 |
4-081 |
•014706 832509 |
6340 |
|
|
69 |
4,761 |
328,509 |
8-306 |
4-101 |
•014493 |
838849 |
6249 |
|
70 |
4,900 |
343,000 |
8-366 |
4-121 |
•014286 |
845098 |
6160 |
|
71 |
5,041 |
357,911 |
8426 |
4-140 |
•014085 851258 |
6074 |
|
|
72 |
5,184 |
373,248 |
8-485 |
4-160 |
•013889 857332 |
5991 |
|
|
73 |
5,329 |
389,017 |
8*644 |
4-179 |
•013699 863323 5909 |
||
|
74 |
5,476 |
405,224 |
8-602 |
4-198 |
•013514 869232 5829 |
GENERAL MATHEMATICAL TABLES.
|
No. |
Square. |
Cube. |
Square Boot, |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
75 |
5,625 |
421,875 |
8-660 |
4-217 |
•013333 |
875061 |
5753 |
|
76 |
5,770 |
438,976 |
8-717 |
4-235 |
•013158 |
880814 |
5677 |
|
77 |
5,929 |
456,533 |
8-744 |
4-254 |
•012987 |
886491 |
5604 |
|
78 |
6,084 |
474,552 |
8-831 |
4-272 |
•012821 |
892095 |
5532 |
|
79 |
6,241 |
493,039 |
8-888 |
4-290 |
•012658 |
897627 |
5463 |
|
80 |
6,400 |
512,000 |
8-944 |
4-308 |
•012500 |
903090 |
5395 |
|
81 |
6,561 |
531.441 |
9-000 |
4-326 |
•012346 |
908485 |
5329 |
|
82 |
6.724 |
551,368 |
9-055 |
4-344 |
•012195 |
913814 |
5264 |
|
83 |
6,889 |
571,787 |
9-110 |
4-362 |
•012048 |
919078 |
5201 |
|
84 |
7,056 |
592,704 |
9-165 |
4-379 |
•011905 |
924279 |
5140 |
|
85 |
7,225 |
614,125 |
9-219 |
4-396 |
•011765 |
929419 |
5079 |
|
86 |
7,396 |
636,056 |
9-273 |
4-414 |
•011628 |
934498 |
5021 |
|
87 |
7,5(59 |
658,503 |
9-327 |
4-431 |
•011494 |
939519 |
4964 |
|
88 |
7.744 |
681,472 |
9-380 |
4-447 |
•011364 |
944483 |
4907 |
|
89 |
7/J21 |
704,969 |
9-433 |
4-461 |
•011236 |
949390 |
4853 |
|
90 |
8,100 |
729,000 |
9-486 |
4-481 |
•011111 |
954243 |
4798 |
|
91 |
8,281 |
753,571 |
9-539 |
4-497 |
•010989 |
959041 |
4747 |
|
92 |
8,464 |
778,688 |
9-591 |
4-514 |
•010870 |
963788 |
4695 |
|
93 |
8,649 |
804,357 |
9-643 |
4-530 |
•010753 |
968483 |
4645 |
|
94 |
8,836 |
830,584 |
9-695 |
4-546 |
•010638 |
973128 |
4596 |
|
95 |
9,025 |
857.375 |
9-746 |
4-562 |
•010526 |
977724 |
4547 |
|
96 |
9,216 |
884^36 |
9-797 |
4-578 |
•010417 |
982271 |
4501 |
|
97 |
9,409 |
912,673 |
9-848 |
4-594 |
•010309 |
986772 |
4454 |
|
98 |
9,604 |
941,192 |
9-899 |
4-610 |
•010204 |
991226 |
4409 |
|
99 |
9,801 |
970,299 |
9-949 |
4-626 |
•010101 |
995635 |
4360 |
|
100 |
10,000 |
1,000,000 |
10-000 |
4-641 |
•010000 |
000000 |
4321 |
|
101 |
10,201 |
,030,301 |
10-049 |
4-657 |
•009901 |
004321 |
4279 |
|
102 |
10,404 |
,061,208 |
10-099 |
4-672 |
•009804 |
008600 |
4237 |
|
103 |
10,609 |
,092,727 |
10-148 |
4-687 |
•009709 |
012837 |
4196 |
|
104 |
10,816 |
,124,864 |
10-198 |
4-702 |
•009615 |
017033 |
4156 |
|
105 |
11,025 |
,157,625 |
10-246 |
4-717 |
•009524 |
021189 |
4117 |
|
106 |
11,236 |
,191,016 |
10-295 |
4-732 |
•009434 |
025306 |
4078 |
|
107 |
11,449 |
,225,043 |
10-344 |
4-747 |
•009346 |
029384 |
4040 |
|
108 |
11,664 |
,259,712 |
10-392 |
4-762 |
•009259 |
033424 |
4002 |
|
109 |
11,881 |
,295,029 |
10-440 |
4-776 |
•009174 |
037426 |
3967 |
|
110 |
12,100 |
,331,000 |
10-488 |
4-791 |
•009091 |
041393 |
3930 |
|
111 |
12,321 |
,367,631 |
10-535 |
4-805 |
•009009 |
045323 |
3895 |
|
112 |
12,554 |
,404,928 |
10-583 |
4-820 |
•008929 |
049218 |
3860 |
|
113 |
12,769 |
,442,897 |
10-630 |
4-834 |
•008850 |
053078 |
3827 |
|
114 |
12,996 |
,481,544 |
10-677 |
4-848 |
•008772 |
056905 |
3793 |
|
115 |
13,225 |
,520,875 |
10-723 |
4-862 |
•008696 |
060698 |
3760 |
|
116 |
13,456 |
,560,896 |
10-^70 |
4-876 |
•008621 |
064458 |
3728 |
|
117 |
13,689 |
,601,613 |
10-816 |
4-890 |
•008547 |
068186 |
3696 |
|
118 |
13,924 |
,643,032 |
10-862 |
4-904 |
•008475 |
071882 |
3665 |
|
119 |
14,161 |
,685,159 |
10-908 |
4-918 |
•008403 |
075547 |
3634 |
B 2
GAS ENGINEER'S POCKET-BOOK,
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
120 |
14,400 |
1,728,000 10-954 |
4-932 |
•008333 |
079181 |
3604 |
|
|
121 |
14,641 |
1,771,561 11-000 |
4-946 |
•008264 |
082785 |
3575 |
|
|
122 |
14,884 |
1,815,848 jll-045 |
4-959 |
•008197 |
086360 |
3545 |
|
|
123 |
15,129 |
1,860,867 111-090 |
4-973 |
•008130 |
089905 |
3517 |
|
|
124 |
15,376 |
1,906,624 111-135 |
4-986 |
•008065 |
093422 |
3488 |
|
|
125 |
15,625 |
1,953,125 11-180 |
5-000 |
•008000 096910 |
3461 |
||
|
126 15,876 |
2,000,376 11-224 |
5-013 |
•007937 |
100371 |
3433 |
||
|
127 |
16,129 |
2,048,383 11-269 |
5-026 |
•007874 |
103804 |
3406 |
|
|
128 |
16,384 |
2,097,152 11-313 |
5-039 |
•007813 |
107210 |
3380 |
|
|
129 |
16,641 |
2.146,689 11-357 |
5-052 |
•007752 |
110590 |
3343 |
|
|
130 |
16,900 |
2,197,000 |
11-401 |
5-065 |
•007692 |
113943 |
3328 |
|
131 |
17,161 |
2,248,091 |
11-445 |
5-078 |
•007634 |
117271 |
3303 |
|
132 |
17,424 |
2,299,968 |
11-489 |
5-091 |
•007576 |
120574 |
3278 |
|
133 |
17.689 |
2,352,637 |
11-532 |
5-104 |
•007519 |
123852 |
3253 |
|
134 |
17^956 |
2,406,104 |
11-575 |
5-117 |
•007463 |
127105 |
3229 |
|
135 |
18,225 |
2,460,375 |
11-618 |
5-129 |
•007407 |
130334 |
3205 |
|
136 |
18,496 |
2,515,456 |
11-661 |
5-142 |
•007353 |
133539 |
3182 |
|
137 |
18,769 |
2,571,353 |
11-704 |
5-155 |
•007299 |
136721 |
3148 |
|
138 |
19,044 |
2,620,872 |
11-747 |
5-167 |
•007246 |
139879 |
3136 |
|
139 |
19,321 |
2,685,619 |
11-789 |
5-180 |
•007194 |
143015 |
3113 |
|
140 |
19,600 |
2,744,000 |
11-832 |
5-192 |
•007143 |
146128 |
3091 |
|
141 |
19,881 |
2,803,221 |
11-874 |
5-204 |
•007092 |
149219 |
3069 |
|
142 |
20,164 |
2,863,288 |
11-916 |
5-217 |
•007042 |
152288 |
3048 |
|
143 |
20,449 |
2,924,207 |
11-958 |
5-229 |
•006993 |
155336 |
3026 |
|
144 |
20,736 |
2,985,984 |
12-000 |
5-241 |
•006944 |
158362 |
3006 |
|
145 |
21,025 |
3,048,625 |
12-041 |
5-253 |
•006897 |
161368 |
2985 |
|
146 |
21,316 |
3,112,136 |
12-083 |
5-265 |
•006849 |
164353 |
2964 |
|
147 |
21,609 |
3.176,523 |
12-124 |
5-277 |
•006803 |
167317 |
2945 |
|
148 |
21,904 |
3,241,792 |
12-165 |
5-289 |
•006757 |
170262 |
2924 |
|
149 |
22,201 |
3,307,949 |
12-206 |
5-301 |
•006711 |
173186 |
2905 |
|
150 |
22,500 |
3,375,000 |
12-247 |
5-313 |
•006667 |
176091 |
2886 |
|
151 |
22,801 |
3.442,951 |
12-288 |
5-325 |
•006623 |
178977 |
2867 |
|
152 |
23.104 |
3,511,808 |
12-328 |
5-336 |
•006579 |
181844 |
2847 |
|
153 |
23,409 |
3,581,577 |
12-369 |
5-348 |
•006536 |
184691 |
2830 |
|
154 |
23,716 |
3,652,264 |
12-409 |
5-360 |
•006494 |
187521 |
2811 |
|
155 |
24,025 |
3,723,875 |
12-449 |
5-371 |
•006452 |
190332 |
2793 |
|
156 |
24,336 |
3,796,416 |
12-489 |
5-383 |
•006410 |
193125 |
2775 |
|
157 |
24,649 |
3,869,893 |
12-529 |
5-394 |
•006369 |
195900 |
2757 |
|
158 |
24,964 |
3,944,312 |
12-569 |
5-406 |
•006329 |
198657 |
2740 |
|
159 |
25,281 |
4,019,679 |
12-609 |
5-417 |
•006289 |
201397 |
2723 |
|
160 |
25,600 |
4,096,000 |
12-649 |
5-428 |
•006250 |
204120 |
2706 |
|
161 |
25,921 |
4,173,281 |
12-688 |
5-440 |
•006211 |
206826 |
2689 |
|
162 |
26,244 |
4,251,528 |
12-727 |
5-451 |
•006173 |
209515 |
2673 |
|
163 |
26,569 |
4,330,747 |
12-767 |
5-462 |
•006135 |
212188 |
2656 |
|
164 |
26,896 |
4,410,944 |
12-806 |
5-473 |
•006098 |
214844 |
2640 |
GENERAL MATHEMATICAL TABLES.
|
Xo. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
165 |
27,225 |
4,492,125 |
12-845 |
5-484 |
•006061 |
217484 |
2624 |
|
166 |
27,556 |
4,574,296 |
12-884 |
5-495 |
•006024 |
220108 |
2608 |
|
167 |
27,889 |
4,657,463 |
12-922 |
5-506 |
•005988 |
222716 |
2583 |
|
168 |
28,224 |
4,741,632 |
12-961 |
5-517 |
•005952 |
225309 |
2578 |
|
169 |
28,561 |
4,826,809 |
13-000 |
5-528 |
•005917 |
227887 |
2562 |
|
170 |
28,900 |
4,913,000 |
13-038 |
5-539 |
•005882 |
230449 |
2547 |
|
171 |
29,241 |
5,000,211 |
13-076 |
5-550 |
•005848 |
232996 |
2532 |
|
172 |
29,584 |
5,088,448 |
13-114 |
5-561 |
•005814 |
235528 |
2518 |
|
173 |
29,929 |
5,177,717 |
13-152 |
5-572 |
•005780 |
238046 |
2503 |
|
174 |
30,276 |
5,268,024 |
13-190 |
5-582 |
•005747 |
240549 |
2489 |
|
175 |
30,625 |
5,359,576 |
13-228 |
5-593 |
•005714 |
243038 |
2475 |
|
176 |
30,976 |
5,451,776 |
13-266 |
5-604 |
•005682 |
245513 |
2460 |
|
177 |
31.329 |
5,545,233 |
13-304 |
5-614 |
•005650 |
247973 |
2447 |
|
178 |
31,684 |
5,639,752 |
13-341 |
5-625 |
•005618 |
250420 |
2433 |
|
179 |
32,041 |
5,735,339 |
13-379 |
5-635 |
•005587 |
252853 |
2420 |
|
180 |
32,400 |
5,832,000 |
13-416 |
5-646 |
•005556 |
255273 |
2406 |
|
181 |
32,761 |
5,929,741 |
13-453 |
5-656 |
•005525 |
257679 |
2392 |
|
182 |
33,124 |
6,028,568 |
13-490 |
5-667 |
•005495 |
260071 |
2380 |
|
183 |
33,489 |
6,128,487 |
13-527 |
.5-677 |
•005464 |
262451 |
2367 |
|
184 |
33,856 |
6,229,504 |
13-564 |
5-687 |
•005435 |
264818 |
2354 |
|
185 |
34,225 |
6,331,625 |
13-601 |
5-698 |
•005405 |
267172 |
2311 |
|
186 |
34,596 |
6,434,856 |
13-638 |
5-708 |
•005376 |
269513 |
2329 |
|
187 |
34,969 |
6,539,203 |
13-674 |
5-718 |
•005348 |
271842 |
2316 |
|
188 |
35,344 |
6,644,672 |
13-711 |
5-728 |
•005319 |
274158 |
2304 |
|
189 |
35,721 |
6,751,269 |
13-747 |
5-738 |
•005291 |
276462 |
2292 |
|
190 |
36,100 |
6,859,000 |
13-784 |
5-748 |
•005263 |
278754 |
2279 |
|
191 |
36,481 |
6,967,871 |
13-820 |
5-758 |
•005236 |
281033 |
2268 |
|
192 |
36,864 |
7,077,888 |
13-856 |
5-768 |
•005208 |
283301 |
2256 |
|
193 |
37,249 |
7,189,057 |
13-892 |
5-778 |
•005181 |
285557 |
2245 |
|
194 |
37,636 |
7,301,384 |
13-928 |
5-788 |
•005155 |
287802 |
2233 |
|
195 |
38,025 |
7,414,875 |
13-964 |
5-798 |
•005128 |
290035 |
2221 |
|
196 |
38,416 |
7,529.536 |
14-000 |
5-808 |
•005102 |
292256 |
2210 |
|
197 |
38,809 |
7,645,373 |
14-035 |
5-818 |
•005076 |
294466 |
2199 |
|
198 |
39,204 |
7,762,392 |
14-071 |
5-828 |
•005051 |
296665 |
2188 |
|
199 |
39,601 |
7,880,599 |
14-106 |
5-838 |
•005025 |
298853 |
2177 |
|
200 |
40,000 |
8,000.000 |
14-142 |
5-848 |
•005000 |
301030 |
2166 |
|
201 |
40,401 |
8,120,601 |
14-177 |
5-857 |
•004975 |
303196 |
2155 |
|
202 |
40,804 |
8,242,408 |
14-212 |
5-867 |
•004950 |
305351 |
2145 |
|
203 |
41,209 |
8,365,427 |
14-247 |
5-877 |
•004926 |
307496 |
2134 |
|
204 |
41,616 |
8,489,664 |
14-282 |
5-886 |
•004902 |
309630 |
2124 |
|
205 |
42,025 |
8.615,125 |
14-317 |
5-896 |
•004878 |
311754 |
2113 |
|
206 |
42,436 |
8,741,816 |
14-352 |
5-905 |
•004854 |
313867 |
2103 |
|
207 |
42,849 |
8,869,743 |
14-387 |
5-915 |
•004831 |
315970 |
2093 |
|
208 |
43,264 |
8,998,912 |
14-422 |
5-924 |
•004808 |
318063 |
2083 |
|
209 |
43,681 |
9,123,329 |
14-456 |
5-934 |
•004785 |
320146 |
2073 |
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
210 |
44,100 |
9.261,000 |
14-491 |
5-943 |
•004762 |
322219 |
2063 |
|
211 |
44,521 |
9^393,931 |
14-525 |
5-953 |
•004739 |
324282 |
2054 |
|
212 |
44,944 |
9,528,128 |
14-560 |
5-962 |
•004717 |
326336 |
2044 |
|
213 |
45,369 |
9,663,597 |
14-594 |
5-972 |
•004695 |
328380 |
2034 |
|
214 |
45,796 |
9,800,344 |
14-628 |
5-981 |
•004673 |
330414 |
2024 |
|
215 |
46,225 |
9.938,375 |
14-662 |
5-990 |
•004651 |
332438 |
2016 |
|
216 |
46,656 |
10^077,696 |
14-696 |
6-000 |
•004630 |
334454 |
2006 |
|
217 |
47,089 |
10,218,313 |
14-730 |
6-009 |
•004608 |
336460 |
1996 |
|
218 |
47,524 |
10,360,232 |
14-764 |
6-018 |
•004587 |
338456 |
1988 |
|
219 |
47,961 |
10,503,459 |
14-798 |
6-027 |
•004566 |
340444 |
1979 |
|
220 |
48,400 |
10.648,000 |
14-832 |
6-036 |
•004545 |
342423 |
1969 |
|
221 |
48,841 |
10,793,861 |
1466-8 |
6-045 |
•004525 |
344392 |
1961 |
|
222 |
49,284 |
10,941,048 |
14-899 |
6-055 |
•004505 |
346353 |
1952 |
|
223 |
49,729 |
11,089,567 |
14-933 |
6-064 |
•004484 |
348305 |
1943 |
|
224 |
50,176 |
11,239,424 |
14-966 |
6-073 |
•004464 |
350248 |
1 1)35 |
|
225 I 50,625 |
11,390,625 |
15-000 |
6-082 |
•004444 |
352183 |
1925 |
|
|
226 |
51,076 |
11,543,176 |
15-033 |
6-091 |
•004425 |
354108 |
1918 |
|
227 |
51,529 |
11,697,083 |
15-066 |
6-100 |
•004405 |
356026 |
1909 |
|
228 |
51,984 |
11,852,352 |
15-099 |
6-109 |
•004386 |
357935 |
1900 |
|
229 |
52,441 |
12,008>89 |
15-132 |
6-118 |
•004367 |
359835 |
1893 |
|
230 |
52,900 |
12,167,000 |
15-165 |
6-126 |
•004348 |
361728 |
1884 |
|
231 |
53,361 |
12,326,391 |
15-198 |
6-135 |
•004329 |
363(512 |
1876 |
|
232 |
53,824 |
12,487,168 |
15-231 |
6-144 |
•004310 |
365488 |
1868 |
|
233 |
54,289 |
12,649,337 |
15-264 |
6-153 |
•004292 |
367356 |
I860 |
|
234 |
54,756 |
12,812,904 |
15-297 |
6-162 |
•004274 |
369216 |
1852 |
|
235 |
55,225 |
12,977,875 |
15-329 |
6-171 |
•004255 |
371068 |
1844 |
|
236 |
55,696 |
13,144.256 |
15-362 |
6-179 |
•004237 |
372912 |
1836 |
|
237 |
56,169 |
13,312,053 |
15-394 |
6-188 |
•004219 |
374748 |
1829 |
|
238 |
56,644 |
13,481,272 |
15-427 |
6-197 |
•004202 |
376577 |
1821 |
|
239 |
57,121 |
13,651,919 |
15-459 |
6-205 |
•004184 |
378398 |
1813 |
|
240 |
57,600 |
13,824,000 |
15-491 |
6-214 |
•004167 |
380211 |
1806 |
|
241 |
58,081 |
13,997,521 |
15-524 |
6-223 |
•004149 |
382017 |
1798 |
|
242 |
58,564 |
14,172,488 |
15*556 |
6-231 |
•004132 |
383815 |
1 791 |
|
243 |
59,049 |
14,348,907 |
15-588 |
6-240 |
•004115 |
385606 |
1784 |
|
244 |
59,536 |
14,526,784 |
15-620 |
6-248 |
•004098 |
387390 |
1776 |
|
245 |
60,025 |
14,706,125 |
15-652 |
6-257 |
•004082 |
389166 |
1 769 |
|
246 |
60,516 |
14,886,936 |
15-684 |
6-265 |
•004065 |
390935 |
1762 |
|
247 |
61,009 |
15,069,223 |
15-716 |
6-274 |
•004049 |
392697 |
1 75 5 |
|
248 |
61,504 |
15,252.992 |
15-748 |
6-282 |
•004032 |
394452 |
1747 |
|
249 |
62,001 |
15,438,249 |
15-779 |
6-291 |
•004016 |
396199 |
1741 |
|
250 |
62.500 |
15,625,000 |
15-811 |
6-299 |
•004000 |
397940 |
1734 |
|
251 |
63,001 |
15,813,251 |
15-842 |
6-307 |
•003984 |
399674 |
1727 |
|
252 |
63,504 |
16,003,008 |
15-874 |
6-316 |
•0039(58 |
401401 |
1720 |
|
253 |
64,009 |
16,194,277 |
15-905 |
6-324 |
•003953 |
403121 |
1713 |
|
254 |
64,516 |
16,387,064 |
15-937 |
6-333 |
•003937 |
404834 1706 |
GENERAL MATHEMATICAL TABLES.
|
Xo. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
255 |
65,025 |
16,581,375 |
15-908 |
0-341 |
•003922 |
400540 |
1700 |
|
256 |
65,536 |
16,777,216 |
10-000 |
0-349 |
•003906 |
408240 |
1693 |
|
257 |
66,019 |
16,974,593 |
10-031 |
0-357 |
•003891 |
409933 |
1087 |
|
258 |
66,564 |
17,173,512 |
10-002 |
6-306 |
•003876 |
411020 |
1680 |
|
259 |
67,081 |
17,373,979 |
16-093 |
6-374 |
•003801 |
413300 |
1073 |
|
260 |
67,600 |
17,576,000 |
10-124 |
6-382 |
•003840 |
414973 |
1668 |
|
261 |
68,121 |
17,779.581 |
10-155 |
0-390 |
•003831 |
410041 |
1060 |
|
262 |
68,644 |
17.984,728 |
10-186 |
6-398 |
•003817 |
418301 |
1655 |
|
263 |
69,169 |
18^191,447 |
10-217 |
0-400 |
•003802 |
419950 |
1048 |
|
264' 69,«96 |
18,399,744 |
10-248 |
6-415 |
•003788 |
421004 |
1042 |
|
|
265 |
70,225 |
18,609,625 |
16-278 |
0-423 |
•003774 |
423240 |
1636 |
|
266 |
70,756 |
18,821,096 |
10-309 |
6-431 |
•003759 |
424882 |
1029 |
|
267 |
71,289 |
19,034,103 |
10-340 |
0-439 |
•003745 |
420511 |
1024 |
|
268 |
71,824 |
19,248,832 |
10-370 |
0-447 |
•003731 |
428135 |
1017 |
|
269 |
72,361 |
19.405,109 |
10-401 |
6-455 |
•003717 |
429752 |
1012 |
|
270 |
72,900 |
19,083,000 |
16-431 |
0-403 |
•003704 |
431364 |
1005 |
|
271 |
73,441 |
19,902,511 |
16-402 |
0-471 |
•003090 |
432909 |
1000 |
|
272 |
73,984 |
20,123,648 |
10-492 |
0-479 |
•003076 |
434509 |
1594 |
|
273 |
74,529 |
20,340,417 |
10-522 |
0-487 |
•003003 |
430103 |
1588 |
|
274 |
75,076 |
20,570,824 |
16-552 |
0-495 |
•003050 |
437751 |
1582 |
|
275 |
75,625 |
20,790,875 |
10,583 |
0-502 |
•003030 |
439333 |
1576 |
|
276 |
70,176 |
21,024,570 |
10-013 |
6-510 |
•003023 |
440909 |
1571 |
|
277 |
76,729 |
21,253,933 |
16-043 |
6-518 |
•003610 |
442480 |
1505 |
|
278 |
77,284 |
21,484,952 |
16-073 |
0-520 |
•003597 |
444045 |
1559 |
|
279 |
77,841 |
21,717,039 |
10-703 |
6-534 |
•003584 |
445004 |
1554 |
|
280 |
78,400 |
21,952,000 |
10-733 |
6-542 |
•003571 |
447158 |
1548 |
|
281 |
78,961 |
22,188,041 |
10-703 |
0-549 |
•003559 |
448700 |
1543 |
|
282 |
79,524 |
22.425,768 |
10-792 |
6-557 |
•003516 |
450249 |
1537 |
|
283 |
80,089 |
22,005,187 |
10-822 |
6-565 |
•003534 |
451786 |
1532 |
|
284 |
80,f>56 |
22,900,304 |
10-852 |
6-573 |
•003522 |
453318 |
1527 |
|
285 |
81,225 |
23,149,125 |
10-881 |
6-580 |
•003509 |
454845 |
1521 |
|
286 |
81,796 |
23,393,050 |
10-911 |
6-588 |
•003497 |
450300 |
1510 |
|
287 |
82,369 |
23,039,903 |
10-941 |
6-590 |
•003484 |
457882 |
1510 |
|
288 |
82.944 |
23,887,872 |
16-970 |
6-003 |
•003472 |
459392 |
1506 |
|
289 |
83^21 |
24,137,569 |
17-000 |
6-611 |
•003400 |
400898 |
1500 |
|
290 |
84.100 |
24,389,000 |
17-029 |
6-619 |
•003448 |
402398 |
1495 |
|
291 |
84^81 |
24,042,171 |
17-059 |
6-027 |
•003430 |
403893 |
1490 |
|
292 |
85,264 |
24,897,088 |
17-088 |
0-034 |
•003425 |
405383 |
1485 |
|
293 |
85,849 |
25,153,757 |
17-117 |
0-642 |
•003413 |
400868 |
1479 |
|
294 |
86,436 |
25,412.184 |
17-140 |
•6-649 |
•003401 |
468347 |
1475 |
|
295 |
87,025 |
25,072^375 |
17-176 |
6-657 |
•003390 |
469822 |
1470 |
|
296 |
87,616 |
25.934.330 |
17-205 |
0-664 |
•003378 |
471292 |
1404 |
|
297 |
88,209 |
26J 98,073 |
17-234 |
0-672 |
•003307 |
472756 |
1400 |
|
298 |
88.804 |
26.403,592 |
17-203 |
0-679 |
•003350 |
474216 |
1455 |
|
299 |
89^01 |
20^30.899 |
17-292 0-687 |
•003344 |
475671 |
1450 |
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
300 |
90.000 |
27,000,000 |
17-320 |
6-694 |
•003333 |
477121 |
1445 |
|
301 |
90^601 |
27,270,901 |
17-349 |
6-702 |
•003322 |
478566 |
1441 |
|
302 |
91,204 |
27,543,608 |
17-378 |
6-709 |
•003311 |
480007 |
1436 |
|
303 |
91,809 |
27,818,127 |
17-407 |
6-717 |
•003301 |
481443 |
1431 |
|
304 |
92,416 |
28,094,464 |
17-436 |
6-724 |
•003289 |
482874 |
1426 |
|
305 |
93,025 |
28,372,625 |
17-464 |
6-731 |
•003279 |
484300 |
1421 |
|
306 |
93.636 |
28,652,616 |
17-493 |
6-739 |
•003268 |
485721 |
1417 |
|
307 |
94,249 |
28,934,443 |
17-521 |
6-746 |
•003257 |
487138 |
1413 |
|
308 |
94,864 |
29,218,112 |
17-549 |
6.753 |
•003247 |
488551 |
1407 |
|
309 |
95,481 |
29,503,629 |
17-578 |
6-761 |
•003236 |
489958 |
1404 |
|
310 |
96,100 |
29,791,000 |
17-607 |
6-768 |
•003226 |
491362 |
1398 |
|
311 |
96,721 |
30,080,231 |
17*635 |
6-775 |
•003215 |
492760 |
1395 |
|
312 |
97,344 |
30,371.328 |
17-663 |
6-782 |
•003205 |
494155 |
1389 |
|
313 |
97,969 |
30,664,297 |
17-692 |
6-789 |
•003195 |
495544 |
1386 |
|
314 |
98.596 |
30,959.144 |
17-720 |
6-797 |
•003185 |
496930 |
1381 |
|
315 |
99,225 |
31,255,875 |
17,748 |
6-804 |
•003175 |
498311 |
1376 |
|
316 |
99,856 |
31,554,496 |
17-776 |
6-811 |
•003165 |
499687 |
1372 |
|
317 |
100,489 |
31,855,013 |
17-804 |
6-818 |
•003155 |
501059 |
1368 |
|
318 |
101,124 |
32,157,432 |
17-832 |
6-826 |
•003145 |
502427 |
1364 |
|
319 |
101,761 |
32,461,759 |
17-860 |
6-833 |
•003135 |
503791 |
1359 |
|
320 |
102,400 |
32,768,000 |
17-888 |
6-839 |
•003125 |
505150 |
1355 |
|
321 |
103,041 |
33,076,161 |
17-916 |
6-847 |
•003115 |
506505 |
1351 |
|
322 |
103,684 |
33,386,248 |
17-944 |
6-854 |
•003106 |
507856 |
1347 |
|
323 |
104,329 |
33,698,267 |
17-972 |
6-861 |
•003096 |
509203 |
1342 |
|
324 |
104,976 |
34,012.224 |
18-000 |
6-868 |
•003086 |
510545 |
1338 |
|
325 |
105,625 |
34,328,125 |
18-028 |
6-875 |
•003077 |
511883 |
1335 |
|
326 |
106.276 |
34,645,976 |
18-055 |
6-882 |
•003067 |
513218 |
1330 |
|
327 |
106,929 |
34,965,783 |
18-083 |
6-889 |
•003058 |
514548 |
1326 |
|
328 |
107,584 |
35.287,552 |
18-111 |
6-896 |
•003049 |
515874 |
1322 |
|
329 |
108,241 |
35^611,289 |
18-138 |
6-903 |
•003040 |
517196 |
1318 |
|
330 |
108,900 |
35,937.000 |
18-166 |
6-910 |
•003030 |
518514 |
1314 |
|
331 |
109,561 |
36,264,691 |
18-193 |
6-917 |
•003021 |
519828 |
1310 |
|
332 |
110,224 |
36,594,368 |
18-221 |
6-924 |
•003012 |
521138 |
1306 |
|
333 |
110,889 |
36,926,037 |
18-248 |
6-931 |
•003003 |
522444 |
1302 |
|
334 j 111,556 |
37,259,704 |
18-276 |
6-938 |
•002994 |
523746 |
1299 |
|
|
335 ! 112,225 |
37,595,375 |
18-303 |
6-945 |
•002985 |
525045 |
1294 |
|
|
336 |
112,896 |
37.933,056 |
18-330 |
6-952 |
•002976 |
526339 |
1291 |
|
337 |
113,569 |
38,272,753 |
18-357 |
6-959 |
•002967 |
527630 |
1287 |
|
338 |
114,244 |
38,614,472 |
18-385 |
6-966 |
•002959 |
528917 |
1283 |
|
339 |
114,921 |
38,958,219 |
18-412 |
6-973 |
•002950 |
530200 |
1279 |
|
340 |
115,600 |
39.304,000 |
18-439 |
6-979 |
•002941 |
531479 |
1275 |
|
341 |
116,281 |
39,651,821 |
18-466 |
6-986 |
•002933 |
532754 |
1272 |
|
342 |
116,964 |
40,001,688 18-493 |
6-993 |
•002924 |
534026 |
1268 |
|
|
343 |
117,649 |
40,353,607 |
18-520 |
7-000 |
•002915 |
535294 |
1264 |
|
344 |
118,336 |
40,707,584 |
18-547 |
7-007 |
•002907 |
536558 |
1261 |
GENERAL MATHEMATICAL TABLES,
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
345 |
119,025 |
41,063,625 |
18-574 |
7-014 |
•002899 |
537819 |
1257 |
|
346 |
119,716 |
41,421,736 |
18-601 |
7-020 |
•002890 |
539076 |
1253 |
|
347 |
120,409 |
41,781,923 |
18-628 |
7-027 |
•002882 |
540329 |
1250 |
|
348 |
121,104 |
42.144,192 |
18-655 |
7-034 |
•002874 |
541579 |
1246 |
|
349 |
121,801 |
42,508,549 |
18-681 |
7-040 |
•002865 |
542825 |
1243 |
|
350 |
122,500 |
42.875,000 |
18-708 |
7-047 |
•002857 |
544068 |
1239 |
|
351 |
123,201 |
48,243,551 |
18-735 |
7-054 |
•002849 |
545307 |
1236 |
|
352 |
123,904 |
43,614,208 |
18-762 |
7-061 |
•002841 |
546543 |
1232 |
|
353 |
124,609 |
43,986,977 |
18-788 |
7-067 |
•002833 |
547775 |
1228 |
|
354 |
125,316 |
44,361,864 |
18-815 |
7-074 |
•002825 |
549003 |
1225 |
|
355 |
126,025 |
44,738,875 |
18-842 |
7-081 |
•002817 |
550228 |
1222 |
|
356 |
126.736 |
45,118,016 |
18-868 |
7-087 |
•002809 |
551450 |
1218 |
|
357 |
127,449 |
45,499,293 |
18-894 |
7-094 |
•002801 |
552668 |
1215 |
|
358 |
128,164 |
45,882,712 |
18-921 |
7-101 |
•002793 |
553883 |
1211 |
|
359 |
128,881 |
46,268,279 |
18-947 |
7-107 |
•002786 |
555094 |
1209 |
|
360 |
129,600 |
46,656,000 |
18-974 |
7-114 |
•002778 |
556303 |
1204 |
|
361 |
130,321 |
47,045,881 |
19-000 |
7-120 |
•002770 |
557507 |
1201 |
|
362 |
131,044 |
47,437,928 |
19-026 |
7-127 |
•002762 |
558709 |
1198 |
|
363 |
131,769 |
47,832,147 |
19-052 |
7-133 |
•002755 |
559907 |
1195 |
|
364 |
132.496 |
48,228,544 |
19-079 |
7-140 |
•002747 |
561101 |
1192 |
|
365 |
133,225 |
48,627,125 |
19-105 |
7-146 |
•002740 |
562293 |
1188 |
|
366 |
133,956 |
49,027,896 |
19-131 |
7-153 |
•002732 |
563481 |
1185 |
|
367 |
134,689 |
49,430,863 |
19-157 |
7-159 |
•002725 |
564666 |
1182 |
|
368 |
135,424 |
49,836,032 |
19-183 |
7-166 |
•002717 |
565848 |
1178 |
|
369 |
136,161 |
50,243,409 |
19-209 |
7-172 |
•002710 |
567026 |
1175 |
|
370 |
136,900 |
50,653,000 |
19-235 |
7-179 |
•002703 |
568202 |
1172 |
|
371 |
137,641 |
51,064,811 |
19-261 |
7-185 |
•002695 |
569374 |
1169 |
|
372 |
138,384 |
51,478,848 |
19-287 |
7-192 |
•002688 |
570543 |
1166 |
|
373 |
139,129 |
51,895,117 |
19-313 |
7-198 |
•002681 |
571709 |
1163 |
|
374 |
139,876 |
52,313,624 |
19-339 |
7-205 |
•002674 |
572872 |
1159 |
|
375 |
140,625 |
52,734,375 |
19-365 |
7-211 |
•002667 |
574031 |
1157 |
|
376 |
141,376 |
53,157,376 |
19-391 |
7-218 |
•002660 |
575188 |
1154 |
|
377 |
142,129 |
53,582,633 |
19-416 |
7-224 |
•002653 |
576341 |
1151 |
|
378 |
142,884 |
54,010,152 |
19-442 |
7-230 |
•002646 |
577492 |
1148 |
|
379 |
143,641 |
54,439,939 |
19-468 |
7-237 |
•002639 |
578639 |
1145 |
|
380 |
144,400 |
54,872,000 |
19-493 |
7-243 |
•002632 |
579784 |
1141 |
|
381 |
145,161 |
55,306,341 |
19-519 |
7-249 |
•002625 |
580925 |
1138 |
|
382 |
145,924 |
55,742,968 |
19-545 |
7-256 |
•002618 |
582063 |
1135 |
|
383 |
146,689 |
56,181,887 |
19-570 |
7-262 |
•002611 |
583199 |
1132 |
|
384 |
147,456 |
56,623,104 |
19-596 |
7-26S |
•002604 |
584331 |
1129 |
|
385 |
148,225 |
57,066,625 |
19-621 |
7-275 |
•002597 |
585461 |
1126 |
|
386 |
148,996 |
57.512,456 |
19-647 |
7-281 |
•002591 |
586587 |
1124 |
|
387 |
149,769 |
57,960,603 |
19-672 |
7-287 -002584 |
587711 |
1121 |
|
|
388 |
150,544 |
58,411,072 |
19-698 |
7-294 -002577 |
588832 |
1118 |
|
|
389 |
151,321 |
58,863,869 |
19-723 |
7-299 -002571 |
589950 |
1115 |
10
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
390 |
152,100 |
59,319,000 |
19-748 |
7-306 |
•002564 |
591065 |
1112 |
|
391 |
152,881 |
59,776,471 |
19-774 |
7-312 |
•002558 |
592177 |
1109 |
|
392 |
153,664 |
60,236,288 |
19-799 |
7-319 |
•002551 |
593286 |
1106 |
|
393 |
154,449 |
60,698,457 |
19-824 |
7-325 |
•002545 |
594393 |
1103 |
|
394 |
155,236 |
61,162,984 |
19-849 |
7-331 |
•002538 |
595496 |
1101 |
|
395 |
156,025 |
61,629,875 |
19-875 |
7-337 |
•002532 |
596597 |
1098 |
|
396 |
156,816 |
62,099,136 |
19-899 |
7-343 |
•002525 |
597695 |
1095 |
|
397 |
157,609 |
62,570,773 |
19-925 |
7-349 |
•002519 |
598791 |
1092 |
|
398 |
158,404 |
63,044,792 |
19-949 |
7-356 |
•002513 |
599883 |
1090 |
|
399 |
159,201 |
63,521,199 |
19-975 |
7-362 |
•002506 |
600973 |
1087 |
|
400 |
160,000 |
64,000.000 |
20-000 |
7-368 |
•002500 |
602060 |
1084 |
|
401 |
160,801 |
64,481,201 |
20-025 |
7-374 |
•002494 |
603144 |
1082 |
|
402 |
161,604 |
64,964,808 |
20-049 |
7-380 |
•002488 |
604226 |
1079 |
|
403 |
162,409 |
65,450,827 |
20-075 |
7-386 |
•002481 |
605305 |
1076 |
|
404 |
163,216 |
65,939,264 |
20-099 |
7-392 |
•002475 |
606381 |
1074 |
|
405 |
164,025 |
66,430,125 |
20-125 |
7-399 |
•002469 |
607455 |
1071 |
|
406 |
164,836 |
66,923,416 |
20-149 |
7-405 |
•002463 |
608526 |
1068 |
|
407 |
165,649 |
67,419.143 |
20-174 |
7-411 |
•002457 |
609594 |
1066 |
|
408 |
166,464 |
67,911,312 |
20-199 |
7-417 |
•002451 |
610660 |
1063 |
|
409 |
167,281 |
68,417,929 |
20-224 |
7-422 |
•002445 |
611723 |
1061 |
|
410 |
168,100 |
68,921,000 |
20-248 |
7-429 |
•002439 |
612784 |
1058 |
|
411 |
168,921 |
69,426,531 |
20-273 |
7-434 |
•002433 |
613842 |
1055 |
|
412 |
169,744 |
69,934,528 |
20-298 |
7-441 |
•002427 |
614897 |
1053 |
|
413 |
170,569 |
70,444,997 |
20-322 |
7-447 |
•002421 |
615950 |
1050 |
|
414 |
171,396 |
70,957,944 |
20-347 |
7-453 |
•002415 |
617000 |
1048 |
|
415 |
172,225 |
71,473,375 |
20-371 |
7-459 |
•002410 |
618048 |
1045 |
|
416 |
173,056 |
71,991,296 |
20-396 |
7-465 |
•002407 |
619093 |
1043 |
|
417 |
173.889 |
72,511,713 |
20-421 |
7-471 |
•002398 |
620136 |
1040 |
|
418 |
174,724 |
73,034,632 |
20-445 |
7-477 |
•002392 |
621176 |
1038 |
|
419 |
175..561 |
73,560,059 |
20-469 |
7-483 |
•002387 |
622214 |
1035 |
|
420 |
176,400 |
74,088,000 |
20'494 |
7-489 |
•002381 |
623249 |
1033 |
|
421 |
177,241 |
74,618,461 |
20-518 |
7-495 |
•002375 |
624282 |
1030 |
|
422 |
178,084 |
75.151,448 |
20-543 |
7-501 |
•002370 |
625312 |
1028 |
|
423 |
178,929 |
75,686,967 |
20-567 |
7-507 |
•002364 |
626340 |
1026 |
|
424 |
179,776 |
76,225,024 |
20-591 |
7-513 |
•002358 |
627366 |
1023 |
|
425 |
180,625 |
76,765,625 |
20-615 |
7-518 |
•002353 |
628389 |
1021 |
|
426 |
181,476 |
77,308,776 |
20-639 |
7-524 |
•002347 |
629410 |
1018 |
|
427 |
182,329 |
77,854,483 |
20-664 |
7-530 |
•002342 |
630428 |
1016 |
|
428 |
183,184 |
78,402,752 |
20-688 |
7-536 |
•002336 |
631444 |
1013 |
|
429 |
184,041 |
78,953,589 |
20-712 |
7-542 |
•002331 |
632457 |
1011 |
|
430 |
184,900 |
79,507,000 |
20-736 |
7-548 |
•002326 |
633468 |
1009 |
|
431 |
185,761 |
80,062,991 |
20-760 |
7-554 |
•002320 |
634477 |
1007 |
|
432 |
186,624 |
80,621,568 |
20-785 |
7-559 |
•002315 |
635484 |
1004 |
|
433 |
187,489 |
81,182,737 |
20-809 |
7-565 |
•002309 |
636488 |
1002 |
|
434 |
188,356 |
81,746,504 |
20-833 |
7-571 |
•002304 |
637490 |
999 |
GENERAL MATHEMATICAL TABLES.
11
|
No. |
Square. |
Cube, |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
43.-) |
189,225 |
82,312,875 |
20-857 |
7-577 |
•002299 |
638489 |
997 |
|
436 |
190,09(5 |
82,881,856 |
20-881 |
7-583 |
•002294 |
639486 |
995 |
|
437 |
190,909 |
83,453,453 |
20-904 |
7-588 |
•002288 |
640481 |
993 |
|
438 |
191,844 |
84,027,672 |
20-928 |
7-594 |
•002283 |
641474 |
991 |
|
439 |
192,721 |
84,604,519 |
20-952 |
7-600 |
•002278 |
642465 |
988 |
|
440 |
193,600 |
85,184,000 |
20-976 |
7-606 |
•002273 |
643453 |
986 |
|
441 |
194,481 |
85,766.121 |
21-000 |
7-612 |
•002268 |
644439 |
983 |
|
442 |
195,364 |
86,350,388 |
21-024 |
7-617 |
•002262 |
645422 |
981 |
|
443 |
196,249 |
86,938,307 |
21-047 |
7-623 |
•002257 |
646404 |
979 |
|
444 |
197,136 |
87,528,384 |
21-071 |
7-629 |
•002252 |
647383 |
977 |
|
445 |
198,025 |
88,121.125 |
21-095 |
7-635 |
•002247 |
618360 |
975 |
|
446 i 198,916 |
88,716,536 |
21-119 |
7-640 |
•002242 |
649335 |
973 |
|
|
447 |
199,809 |
89,314,623 |
21-142 |
7-646 |
•002237 |
650308 |
970 |
|
448 |
200,704 |
89,915,392 |
21-166 |
7'652 |
•002232 |
651278 |
968 |
|
449 |
201,601 |
90,518,849 |
21-189 |
7-657 |
•002227 |
652246 |
967 |
|
450 |
202,500 |
91,125,000 |
21-213 |
7-663 |
•002222 |
653213 |
964 |
|
451 |
203,401 |
91,733,851 |
21-237 |
7-669 |
•002217 |
654177 |
962 |
|
452 |
204,304 |
92,345,408 |
21-260 |
7-674 |
•002212 |
655138 |
960 |
|
453 |
205,209 |
92,959,677 |
21-284 |
7-680 |
•002208 |
656098 |
958 |
|
454 |
206,106 |
93,576,664 |
21-307 |
7-686 |
•002203 |
657056 |
956 |
|
455 |
207,025 |
94,196.375 |
21-331 |
7-691 |
•002198 |
658011 |
954 |
|
456 |
207,936 |
94,818,816 |
21-354 |
7-697 |
•002193 |
658965 |
951 |
|
457 |
208,849 |
95,443,993 |
21-377 |
7-703 |
•002188 |
659916 |
949 |
|
458 |
209,764 |
96,071,912 |
21-401 |
7-708 |
•002183 |
660865 |
947 |
|
459 |
210,681 |
96,702,579 |
21-424 |
7-714 |
•002179 |
661813 |
945 |
|
460 |
211,600 |
97,336,000 |
21-447 |
7-719 |
•002174 |
662758 |
943 |
|
461 |
212,521 |
97,972,181 |
21-471 |
7-725 |
•002169 |
663701 |
941 |
|
462 |
213,444 |
98,611,128 |
21-494 |
7-731 |
•002165 |
664642 |
939 |
|
463 |
214,369 |
99,252,847 |
21-517 |
7-736 |
•002160 |
665581 |
937 |
|
464 |
215,296 |
99,897,345 |
21-541 |
7-742 |
•002155 |
666518 |
935 |
|
465)216.225 |
100,544,625 |
21-564 |
7-747 |
•002151 |
667453 |
933 |
|
|
466 217,156 |
101,194,696 |
21-587 |
7-753 |
•002146 |
668386 |
931 |
|
|
467 i 218,089 |
101,847.563 |
21-610 |
7-758 |
•002141 |
669317 |
929 |
|
|
468 |
219,024 |
102,503,232 |
21-633 |
7-764 |
•002137 |
670246 |
927 |
|
469 |
219,961 |
103,161,709 |
21-656 |
7-769 |
•002132 |
671173 |
925 |
|
470 |
220,900 |
103,823,000 |
21-679 |
7-775 |
•002128 |
672098 |
923 |
|
471 |
221,841 |
104,487,111 |
21-702 |
7-780 |
•002123 |
673021 |
921 |
|
472 |
222,784 |
105,154,048 |
21-725 |
7-786 |
•002119 |
673942 |
919 |
|
473 |
223,729 |
105,823,817 |
21-749 |
7-791 |
•002114 |
674861 |
917 |
|
474 |
224,676 |
106,496,424 |
21-771 |
7-797 |
•002110 |
675778 |
915 |
|
475 |
225,625 |
107,171,875 |
21-794 |
7-802 |
•002105 |
676694 |
913 |
|
476 |
226,576 |
107,850,176 |
21-817 |
7-808 |
•002101 |
677607 |
911 |
|
477 |
227,529 |
108,531,333 |
21-840 |
7-813 |
•002096 |
678518 |
910 |
|
478 ! 228,484 |
109,215,352 |
21-863 |
7-819 |
•002092 |
679428 |
908 |
|
|
479 ( 229,441 |
109,902,239 |
21-886 |
7-824 |
•002088 |
680336 |
905 |
12
GAS ENGINEER S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square lioot. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
480 |
230,400 |
110,592,000 |
21-909 |
7-830 |
•002083 |
681241 |
904 |
|
481 |
231,8(51 |
111,284,641 |
21-932 |
7-835 |
•002079 |
682145 |
902 |
|
482 |
232,324 |
111,980,168 |
21-954 |
7-840 |
•002075 |
683047 |
900 |
|
483 |
233,289 |
112,678,587 |
21-977 |
7-846 |
•002070 |
683947 |
898 |
|
484 |
234,256 |
113,379,904 |
22-000 |
7-851 |
•002066 |
684845 |
896 |
|
485 |
235.225 |
114,084,125 |
22-023 |
7-857 |
•002062 |
685742 |
894 |
|
486 |
236,196 |
114,791,256 |
22-045 |
7-862 |
•002058 |
686636 |
893 |
|
487 |
237,169 |
115,501,303 |
22-069 |
7-868 |
•002053 |
687529 891 |
|
|
488 |
238,144 |
116,214,272 |
22-091 |
7-873 |
•002049 |
688420 |
889 |
|
489 |
239,121 |
116,936,169 |
22-113 |
7-878 |
•002045 |
689309 |
887 |
|
490 |
240,100 |
117,649,000 |
22-136 |
7-884 |
•002041 |
690196 |
885 |
|
491 |
241,081 |
118,370,771 |
22-158 |
7-889 |
•002037 |
691081 |
884 |
|
492 |
242,064 |
119,095,488 |
22-181 |
7-894 |
•002033 |
691965 |
882 |
|
493 |
243,049 |
119,823,157 |
22-204 |
7-899 |
•002028 |
692847 |
880 |
|
494 |
244,036 |
120,553,784 |
22-226 |
7-905 |
•002024 |
693727 |
878 |
|
495 |
245,025 |
121,287,375 |
22-248 |
7-910 |
•002020 |
694605 |
876 |
|
496 |
246,016 |
122,023,936 |
22-271 |
7-915 |
•002016 |
695482 |
874 |
|
497 |
247,009 |
122,763,473 |
22-293 |
7-921 |
•002012 |
696356 |
873 |
|
498 |
248,004 |
123,505,992 |
22-316 |
7-926 |
•002008 |
697229 |
871 |
|
499 |
249,001 |
124,251,499 |
22-338 |
7-932 |
•002004 |
698101 |
869 |
|
500 |
250,000 |
125,000,000 |
22-361 |
7-937 |
•002000 |
698970 |
868 |
|
501 |
251,001 |
125,751,501 |
22-383 |
7-942 |
•001996 |
699838 |
866 |
|
502 |
252,004 |
126,506,008 |
22-405 |
7-947 |
•001992 |
700704 |
864 |
|
503 |
253,009 |
127,263,527 |
22-428 |
7-953 |
•001988 |
701568 |
862 |
|
504 |
254,016 |
128,024,864 |
22-449 |
7-958 |
•001984 |
702431 |
860 |
|
505 |
255,025 |
128,787,625 |
22-472 |
7-963 |
•001980 |
703291 |
859 |
|
506 |
256,036 |
129,554,216 |
22-494 |
7-969 |
•001976 |
704151 |
857 |
|
507 |
257,049 |
130,323,843 |
22-517 |
7-974 |
•001972 |
705008 |
856 |
|
508 |
258,064 |
131,096,512 |
22-539 |
7-979 |
•001969 |
705864 |
854 |
|
509 |
259,081 |
131,872,229 |
22-561 |
7-984 |
•001965 |
706718 |
852 |
|
510 |
260,100 |
132,651,000 |
22-583 |
7-989 |
•001961 |
707570 |
851 |
|
511 |
261,121 |
133,432,831 |
22-605 |
7-995 |
•001957 |
708421 |
849 |
|
512 |
262,144 |
134,217,728 |
22-627 |
8-000 |
•001953 |
709270 |
847 |
|
513 |
263,169 |
135,005,697 |
22-649 |
8-005 |
•001949 |
710117 |
846 |
|
514 |
264,196 |
135,796,744 |
22-671 |
8-010 |
•001946 |
710963 |
844 |
|
515 |
265,225 |
136,590,875 |
22-694 |
8-016 |
•001942 |
711807 |
843 |
|
516 |
266,256 |
137,388,096 |
22-716 |
8-021 |
•001938 |
712650 |
841 |
|
517 |
267,289 |
138,188,413 |
22-738 |
8-026 |
•001934 |
713491 |
839 |
|
518 |
268,324 |
138,991,832 |
22-759 |
8-031 |
•001931 |
714330 |
837 |
|
519 |
269,361 |
139,798,359 |
22-782 |
8-036 |
•001927 |
715167 |
836 |
|
520 |
270,400 |
140,608,000 |
22-803 |
8-041 |
•001923 |
716003 |
835 |
|
521 |
271,441 |
141,420,761 |
22-825 |
8-047 |
•001919 |
716838 |
833 |
|
522 |
272,484 |
142,236,648 |
22-847 |
8-052 |
•001916 |
717671 |
831 |
|
523 |
273,529 |
143,055,667 |
22-869 |
8-057 |
•001912 |
718502 |
829 |
|
524 |
274,576 |
143,877,824 |
22-891 |
8-062 |
•001908 |
719331 |
828 |
GENERAL MATHEMATICAL TABLES.
13
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
525 |
275,625 |
144,703,125 |
22-913 |
8-067 |
•001905 |
720159 |
827 |
|
526 |
276,676 |
145,531,576 |
22-935 |
8-072 |
•001901 |
720986 |
825 |
|
527 j 277,729 |
146.363,183 |
22-956 |
8-077 |
•001898 |
721811 |
823 |
|
|
528 278.781 |
147^197,952 |
22-978 |
8-082 |
•001894 |
722634 |
822 |
|
|
529 |
279,841 |
148,035,889 |
23-000 |
8-087 |
•001890 |
723456 |
820 |
|
530 |
280.900 |
148,877,000 |
23-022 |
8-093 |
•001887 |
724276 |
819 |
|
531 281,9(51 |
149,721,291 |
23-043 |
8-098 |
•001883 |
725095 |
817 |
|
|
532 283,024 |
150,568,768 |
23-0(55 |
8-103 |
•001880 |
725912 |
815 |
|
|
533 j 284,089 |
151,419.437 |
23-087 |
8-108 |
•001876 |
726727 |
814 |
|
|
534 285.156 |
152,273,304 |
23-108 |
8-113 |
•001873 |
727541 |
813 |
|
|
535 28(5.225 |
153,130,375 |
23-130 |
8-118 |
•001869 |
728354 |
811 |
|
|
536 |
287,296 |
153.990,656 |
23-152 |
8-123 |
•001866 |
729165 |
809 |
|
537 |
288,3(59 |
154,854,153 |
23-173 |
8-128 |
•001862 |
729974 |
808 |
|
538 |
28!). 444 |
155,720,872 |
23-195 |
8-133 |
•001859 |
730782 |
807 |
|
539 |
290,521 |
156,590,819 |
23-216 |
8-138 |
•001855 |
731589 |
805 |
|
540 |
291,600 |
157,464,000 |
23-238 |
8-143 |
•001852 |
732394 |
803 |
|
541 |
292,681 |
158.340,421 |
23-259 |
8-148 |
•001848 |
733197 |
802 |
|
542 |
293,764 |
159.220,088 |
23-281 |
8-153 |
•001845 |
733999 |
801 |
|
543 |
294,849 |
160^103,007 |
23-302 |
8-158 |
•001842 |
734800 |
799 |
|
544 |
295.936 |
160,989,184 |
23-324 |
8-163 |
•001838 |
735599 |
798 |
|
545 |
297,025 |
161,878,625 |
23-345 |
8-168 |
•001835 |
736397 |
796 |
|
546 |
298,116 |
162,771,336 |
23-367 |
8-173 |
•001832 |
737193 |
794 |
|
547 |
299,209 |
163,667,323 |
23-388 |
8-178 |
•001828 |
737987 |
793 |
|
548 |
300,304 |
164,566,592 |
23-409 |
8-183 |
•001825 |
738781 |
792 |
|
549 |
301 ,401 |
165,469,149 |
23-431 |
8-188 |
•001821 |
739572 |
791 |
|
550 |
302,500 |
166,375,000 |
23-452 |
8-193 |
•001818 |
740363 |
789 |
|
551 |
303,601 |
167,284,151 |
23-473 |
8-198 |
•001815 |
711152 |
787 |
|
552 |
304,704 |
168,296,608 |
23-495 |
8-203 |
•001812 |
741939 |
786 |
|
553 |
305,809 |
169,112,377 |
23-516 |
8-208 |
•001808 |
742725 |
785 |
|
554 |
306,916 |
170,031,464 |
23-537 |
8-213 |
•001805 |
743510 |
783 |
|
555 |
308,025 |
170,953,875 |
23-558 |
8-218 |
•001802 |
744293 |
782 |
|
556 |
309,136 |
171,879,616 |
23-579 |
8-223 |
•001799 |
745075 |
780 |
|
557 |
310,249 |
172,808,693 |
23-601 |
8-228 |
•001795 |
745855 |
779 |
|
558 |
311,364 |
173,741,112 |
23-622 |
8233 |
•001792 |
746634 |
778 |
|
559 |
312,481 |
174,676,879 |
23-643 |
8-238 |
•001789 |
747412 |
776 |
|
560 |
313,600 |
175.616,000 |
23-664 |
8-242 |
•001786 |
748188 |
775 |
|
561 314,721 |
176,558,481 |
23-685 |
8-247 |
•001783 |
748963 |
773 |
|
|
562 315,844 |
177,504,328 |
23-706 |
8-252 |
•001779 |
749736 |
772 |
|
|
563 ; 316,969 |
178,453,547 |
23-728 |
8-257 |
•001776 |
750508 |
771 |
|
|
564 318,096 |
179,406,144 |
23-749 |
8-262 |
•001773 |
751279 |
769 |
|
|
565 . 319,225 |
180,362,125 |
23-769 |
8-267 |
•001770 |
752048 |
768 |
|
|
566 320,356 |
181,321,496 |
23 791 |
8-272 |
•001767 |
752816 |
767 |
|
|
567 |
321,489 |
182,284,263 23-812 |
8-277 |
•001764 |
753583 |
765 |
|
|
568 |
322,624 |
183,250,432 23'833 |
8-282 |
•001761 |
754348 |
764 |
|
|
569 j 323,761 |
184,220,009 23-854 |
8-286 |
•001757 |
755112 |
763 |
14
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Hoot, |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
570 |
324,900 |
185,193,000 |
23-875 |
8-291 |
•001754 |
755875 |
761 |
|
571 |
326,041 |
186,169,411 |
23-896 |
8-296 |
•001751 |
75663(5 |
7GO |
|
572 |
327,184 |
187,149,248 |
23-916 |
8-301 |
•0017-18 |
757396 |
759 |
|
573 |
328,329 |
188.132.517 |
23-937 |
8-306 |
•001745 |
758153 |
757 |
|
574 |
329,476 |
189,119.224 |
23-958 |
8-311 |
•001742 |
758912 |
756 |
|
575 |
330,625 |
190,109,375 |
23-979 |
8-315 |
•001739 |
75^668 |
754 |
|
576 |
331,776 |
191.102,976 |
24-000 |
8-320 |
•001736 |
760422 |
753 |
|
577 |
332,929 |
192,100,033 |
24-021 |
8-325 |
•001733 |
761176 |
752 |
|
578 |
334,084 |
193,100,552 |
24-042 |
8-330 |
•001730 |
761928 |
751 |
|
579 |
335,241 |
194,104,539 |
24062 |
8-335 |
•001727 |
762679 |
749 |
|
580 |
336,400 |
195,112,000 |
24-083 |
8-339 |
•001724 |
763228 |
748 |
|
581 |
337,561 |
196,122,941 |
24-104 |
8-344 |
•001721 |
76417(1 |
747 |
|
582 |
338,724 |
197,137,368 |
24-125 |
8-349 |
•001718 |
764923 |
746 |
|
583 |
339,889 |
198,155,287 |
24-145 |
8-354 |
•001715 |
765669 |
744 |
|
584 |
341,056 |
199,176,704 |
24-166 |
8-359 |
•001712 |
7664 13 |
743 |
|
585 |
342,225 |
200,201,625 |
24-187 |
8-363 |
•001709 |
767156 |
742 |
|
586 |
343,396 |
201,230,056 |
24-207 |
8-368 |
•001706 |
767898 |
740 |
|
587 |
344,569 |
202,262,003 |
24-228 |
8-373 |
•001704 |
768638 |
739 |
|
588 |
345,744 |
203,297,472 |
24-249 |
8-378 |
•001701 |
769377 |
738 |
|
589 |
346,921 |
204,336,469 |
24-269 |
8-382 |
•001698 |
770115 |
737 |
|
590 |
348,100 |
205.379,000 |
24-289 |
8-387 |
•001695 |
770852 |
735 |
|
591 |
349,281 |
206^425,071 |
24-310 |
8-392 |
•001692 |
771587 |
734 |
|
592 |
350,464 |
207.474,688 |
24-331 |
8-397 |
•001689 |
772322 |
733 |
|
593 |
351,649 |
208,527,857 |
24-351 |
8-401 |
•001686 |
773055 |
731 |
|
594 |
352,836 |
209,584,584 |
24-372 |
8-406 |
•001684 |
773786 |
730 |
|
595 |
354,025 |
210,644,875 |
24-393 |
8-411 |
•001681 |
774517 |
729 |
|
596 |
355.216 |
211,708,736 |
24-413 |
8-415 |
•001678 |
775246 |
728 |
|
597 |
356,409 |
212,776,173 |
24-433 |
8-420 |
•001675 |
775974 |
727 |
|
598 |
357,604 |
213,847,192 |
24-454 |
8-425 |
•001672 |
776701 |
726 |
|
599 |
358,801 |
214,921,799 |
24-474 |
8-429 |
•001669 |
777427 |
724 |
|
600 |
360.000 |
216,000,000 |
24-495 |
8-434 |
•001667 |
778151 |
723 |
|
601 |
361,201 |
217,081,801 |
24-515 |
8-439 |
•001664 |
778874 |
722 |
|
602 |
362,404 |
218,167,208 |
24-536 |
8-444 |
•001661 |
779596 |
721 |
|
603 |
363,609 |
219,256,227 |
24-556 |
8-448 |
•001658 |
780317 |
720 |
|
604 |
364816 |
220,348,864 |
24-576 |
8-453 |
•001656 |
781037 |
719 |
|
605 |
366,025 |
221,445,125 |
24-597 |
8-458 |
•001653 |
781755 |
718 |
|
606 |
367,236 |
222,545,016 |
24-617 |
8-462 |
•001650 |
782473 716 |
|
|
607 |
368,449 |
223,648,543 |
24-637 |
8-467 |
•001647 |
783189 715 |
|
|
608 1 369,664 |
224,755,712 |
24-658 |
8-472 |
•001645 |
783904 714 |
||
|
609 |
370,881 |
225.866,529 |
24-678 |
8-476 |
•001642 |
784617 713 |
|
|
610 |
372,100 |
226,981,000 |
24-698 |
8-481 |
•001639 |
785330 '711 |
|
|
611 |
373,321 |
228,099,131 |
24-718 |
8-485 |
•001637 |
786041 |
710 |
|
612 374,544 |
229,220,928 |
24-739 |
8-490 |
•001634 |
786751 |
709 |
|
|
613 375,769 |
230,346,397 |
24-758 |
8-495 |
•001631 |
787460 |
708 |
|
|
614 376,996 |
231,475,544 |
24-779 1 8-499 |
•001629 |
788168 |
707 |
GENERAL MATHEMATICAL TABLES.
15
|
No. |
Squai'e. |
Cube. |
Square Root, |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
615 |
378,225 |
232,608,375 |
24-799 |
8-504 |
•001626 |
788875 |
706 |
|
616 |
379,456 |
233,744,896 |
24-819 |
8-509 |
•001623 |
789581 |
704 |
|
617 |
380,689 |
234,885,113 |
24-839 |
8-513 |
•001621 |
790285 |
703 |
|
618 |
381,924 |
236.029.032 |
24-859 |
8-518 |
•001618 |
790988 |
702 |
|
619 |
383,161 |
237,176,659 |
24-879 |
8-522 |
•001616 |
791691 |
701 |
|
620 |
384,400 |
238,628,000 |
24-899 |
8-527 |
•001613 |
792392 |
700 |
|
621 |
385,641 |
239,483,061 |
24-919 |
8-532 |
•001610 |
793092 |
699 |
|
622 |
386,884 |
240,641,348 |
24-939 |
8-536 |
•001608 |
793790 |
698 |
|
623 |
388,129 |
241,804,367 |
24-959 I 8-541 |
•001605 |
794488 |
697 |
|
|
624 |
389,376 |
242,970,624 |
24-980 |
8-545 |
•001603 |
795185 |
695 |
|
625 |
390,625 |
244,140,625 |
25-000 |
8-549 |
•001600 |
795880 |
694 |
|
626 |
391,876 |
245,314,376 |
25-019 |
8-554 |
•001597 |
796574 |
693 |
|
627 |
393,129 |
246,491.883 |
25-040 |
8-559 |
•001595 |
797268 |
692 |
|
628 |
394,384 |
247,673,152 |
25-059 |
8-563 |
•001592 |
797960 |
691 |
|
629 |
395,641 |
248,858,189 |
25-079 |
8-568 |
•001590 |
798651 |
690 |
|
630 |
396,900 |
250,047,000 |
25-099 |
8-573 |
•001587 |
799341 |
689 |
|
631 |
398,161 |
251,239,591 |
25-119 |
8-577 |
•001585 |
800029 |
688 |
|
632 |
399,424 |
252,435.968 |
25-139 |
8-582 |
•001582 |
800717 |
687 |
|
633 |
400,689 |
253,636,137 |
25-159 |
8-586 |
•001580 |
801404 |
685 |
|
634 |
401,956 |
254,840,104 |
25-179 |
8-591 |
•001577 |
802089 |
684 |
|
635 |
403,225 |
256,047,875 |
25-199 |
8-595 |
•001575 |
802774 |
683 |
|
636 |
404,496 |
257,259,456 |
25-219 |
8-599 |
•001572 |
803457 |
682 |
|
637 |
405,769 |
258.474,853 |
25-239 |
8-604 |
•001570 |
804139 |
681 |
|
638 |
407,044 |
259^694,072 |
25-259 |
8-609 |
•001567 |
804821 |
680 |
|
639 |
408,321 |
260,917,119 |
25-278, |
8-613 |
•001565 |
805501 |
679 |
|
640 |
409,600 |
262,144,000 |
25-298 |
8-618 |
•001563 |
806180 |
678 |
|
641 |
410,881 |
263,374,721 |
2V318 |
8-622 |
•001560 |
806858 |
677 |
|
642 |
412,164 |
264,609,288 |
25-338 |
8-627 |
•001558 |
807535 |
676 |
|
643 |
413,449 |
265,847,707 |
25-357 |
8-631 |
•001555 |
808211 |
675 |
|
644 |
414,736 |
267,089,984 |
25-377 |
8-636 |
•001553 |
808886 |
674 |
|
645 |
416,025 |
268,836,125 |
25-397 |
8-640 |
•001550 |
809560 |
673 |
|
646 |
417,316 |
269,586,136 |
25-416 |
8-644 |
•001548 |
810233 |
672 |
|
647 |
418,609 |
270,840,023 |
25-436 |
8-649 |
•00154(5 |
810904 |
671 |
|
648 |
419,904 |
272,097,792 |
25-456 |
8-653 |
•001543 |
811575 |
670 |
|
649 |
421,201 |
273,359,449 |
25-475 |
8-658 |
•001541 |
812245 |
669 |
|
650 |
422,500 |
274,625,000 |
25-495 |
8-662 |
•001538 |
812913 |
668 |
|
651 |
423,801 |
275,894,451 |
25-515 |
8-667 |
•001536 |
813581 |
667 |
|
652 |
425,104 |
277,167,808 |
25-534 |
8-671 |
•001534, |
814248 |
666 |
|
653 |
426,409 |
278,445,077 |
25-554 |
8-676 |
•001531 |
814913 |
665 |
|
654 |
427,716 |
279,726,264 |
25-573 |
8-680 |
•001529 |
815578 |
664 |
|
655 |
429,025 |
281,011,375 |
25-593 |
8-684 |
•001527 |
816241 |
663 |
|
656 |
430,336 |
282,800,416 |
25-612 |
8-689 |
•001524 |
816904 |
6'52 |
|
657 |
431,649 |
283,593,393 |
25-632 |
8-693 |
•001522 |
817565 |
661 |
|
658 |
432,964 |
284,890,312 |
25-651 |
8-698 |
•001520 |
818226 |
660 |
|
659 |
434.281 |
286,191,179 |
25-671 |
8-702 |
•001517 |
818885 |
659 |
16
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube, |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
660 |
435,600 |
287,496,000 |
25-690 |
8-706 |
•001515 |
819544 |
658 |
|
661 |
436,921 |
288,804.781 |
25-710 |
8-711 |
•001513 |
820201 |
657 |
|
662 |
438,244 |
290,117,528 |
25-720 |
8-715 |
•001511 |
820858 |
656 |
|
663 |
439,569 |
291,434,247 |
25-749 |
8-719 |
•001508 |
821514 |
654 |
|
664 |
440,896 |
292,754,944 |
25-768 |
8-724 |
•001506 |
822168 |
653 |
|
665 |
442,225 |
294,079,625 |
25-787 |
8-728 |
•001504 |
822822 |
652 |
|
666 |
443,556 |
295,408,296 |
25-807 |
8-733 |
•001502 |
823474 |
651 |
|
667 |
444,889 |
296,740,963 |
25-826 |
8-737 |
•001499 |
824126 |
650 |
|
668 |
446,224 |
298,077,632 |
25-846 |
8-742 |
•001497 |
824776 |
650 |
|
669 |
447,561 |
299,418,309 |
25-865 |
8-746 |
•001495 |
825426 |
649 |
|
670 |
448,900 |
300,763,000 |
25-884 |
8-750 |
•001493 |
826075 |
648 |
|
671 |
450,241 |
302,111,711 |
25-904 |
8-753 |
•001490 |
826723 |
647 |
|
672 |
451,584 |
303,464,448 |
25-923 |
8-759 |
•001488 |
827369 |
646 |
|
673 |
452,929 |
304,821,217 |
25-942 |
8-763 |
•001486 |
828015 |
645 |
|
674 |
454,276 |
306,182,024 |
25-961 |
8-768 |
•001484 |
828660 |
644 |
|
675 |
455,625 |
307,546,875 |
25-981 |
8-772 |
•001481 |
829304 |
643 |
|
676 |
456.976 |
308,915,776 |
26-000 |
8-776 |
•001479 |
829947 |
642 |
|
677 |
458,329 |
310,288,733 |
26-019 |
8-781 |
•001477 |
830589 |
641 |
|
678 |
459,684 |
311,665,752 |
26-038 |
8-785 |
•001475 |
831230 |
640 |
|
679 |
461,041 |
313,046,839 |
26-058 |
8-789 |
•001473 |
831870 |
639 |
|
680 |
462,400 |
314,432,000 |
26-077 |
8-794 |
•001471 |
832509 |
638 |
|
681 |
463,761 |
315,821,241 |
26-096 |
8-798 |
•001468 |
833147 |
637 |
|
682 |
465,124 |
317,214,568 |
26-115 |
8-802 |
•001466 |
833784 |
637 |
|
683 |
466,489 |
318.611,987 |
26-134 |
8-807 |
•001464 |
834421 |
636 |
|
684 |
467,856 |
320,013,504 |
26-153 |
8-811 |
•001462 |
835056 |
635 |
|
685 |
469,225 |
321,419,125 |
26-172 |
8-815 |
•001460 |
835691 |
634 |
|
686 |
470.596 |
322,828,856 |
26-192 |
8-819 |
•001458 |
836324 |
633 |
|
687 |
471,969 |
324,242,703 |
26-211 |
8-824 |
•001456 |
836957 |
632 |
|
688 |
473,344 |
325,660,672 |
26-229 |
8-828 |
•001453 |
837588 |
631 |
|
689 |
474,721 |
327,082,769 |
26-249 |
8-832 |
•001451 |
838219 |
630 |
|
690 |
476,100 |
328,509,000 |
26-268 |
8-836 |
•001449 |
838849 |
629 |
|
691 |
477,481 |
329,939,371 |
26-287 |
8-841 |
•001447 |
839478 |
628 |
|
692 |
478,864 |
331,373,888 |
26-306 |
8-845 |
•001445 |
840106 |
627 |
|
693 480,249 |
332,812,557 |
26-325 |
8-849 |
•001443 |
840733 |
626 |
|
|
694 481,636 |
334,255,384 |
26-344 |
8-853 |
•001441 |
841359 |
625 |
|
|
695 483,025 |
335,702,375 |
26-303 |
8-858 |
•001439 |
841985 |
624 |
|
|
696 |
484,416 |
337.153,536 |
26-382 |
8-862 |
•001437 |
842609 |
623 |
|
697 |
485,809 |
338^08,873 |
26-401 |
8-866 |
•001435 |
843233 |
622 |
|
698 |
487,204 |
340,068,392 |
26-419 |
8-870 |
•001433 |
843855 |
622 |
|
699 |
488,601 |
341,532,099 |
26-439 |
8-875 |
•001431 |
844477 |
621 |
|
700 |
490,000 |
343,000,000 |
26-457 |
8-879 |
•001429 |
845098 |
620 |
|
701 |
491.401 |
344,472,101 |
26-476 |
8-883 |
•001427 |
845718 |
619 |
|
702 |
492^04 |
345.948,088 |
26-495 |
8-887 |
•001425 |
846337 |
618 |
|
703 |
494,209 |
347,528.927 |
26-514 |
8-892 |
•001422 |
846955 |
617 |
|
704 |
495,616 |
348,913,664 |
26-533 |
8-896 |
•001420 |
847573 |
616 |
GENERAL MATHEMATICAL TABLES.
17
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
705 |
497,025 |
350,402,625 |
26-552 |
8-900 |
•001418 |
848189 |
615 |
|
706 |
498,430 |
351,895,816 |
26-571 |
8-904 |
•001416 |
848805 |
614 |
|
707 |
499,849 |
353,393,243 |
26-589 |
8-908 |
•001414 |
849419 |
614 |
|
708 |
501.264 |
354,894,912 |
26-608 |
8-913 |
•001412 |
850033 |
613 |
|
709 |
502,681 |
356,400,829 |
26-627 |
8-917 |
•001410 |
850646 |
612 |
|
710 |
504,100 |
357,911,000 |
26-644 |
8-921 |
•001408 |
851258 |
611 |
|
711 |
505,521 |
359,425,431 |
26-664 |
8-925 |
•001406 |
851870 |
610 |
|
712 |
50(5,944 |
360,944.128 |
26-683 |
8-929 |
•001404 |
852480 |
610 |
|
713 |
508,369 |
362.467^097 |
26-702 |
8-934 |
•001403 |
853090 |
609 |
|
714 |
509,796 |
363,994.344 |
26-721 |
8-938 |
•001401 |
853698 |
608 |
|
715 |
511,225 |
365,525,875 |
26-739 |
8-942 |
•001399 |
854306 |
607 |
|
716 |
512,656 |
367,061,696 |
26-758 |
8-946 |
•001397 |
854913 |
606 |
|
717 |
514,089 |
368,601,813 |
26-777 |
8-950 |
•001395 |
855519 |
605 |
|
718 |
515,524 |
370,146,232 |
26-795 |
8-954 |
•001393 |
856124 |
604 |
|
719 |
516,961 |
371,694,959 |
26-814 |
8-959 |
•001391 |
856729 |
603 |
|
720 |
518,400 |
373,248,000 |
26-833 |
8-963 |
•001389 |
857332 |
603 |
|
721 |
519,841 |
374,805,361 |
26-851 |
8-967 |
•001387 |
857935 |
602 |
|
722 |
521,284 |
376,367,048 |
26-870 |
8-971 |
•001385 |
858537 |
601 |
|
723 |
522,729 |
377,933,067 |
26-889 |
8-975 |
•001383 |
859138 |
600 |
|
724 |
524,176 |
379,503,424 |
26-907 |
8-979 |
•001381 |
859739 |
599 |
|
725 |
525,625 |
381,078,125 |
26-926 |
8-983 |
•001379 |
860338 |
598 |
|
726 |
527,076 |
382,657,176 |
26-944 |
8-988 |
•001377 |
860937 |
597 |
|
727 |
528,529 |
384,240,583 |
26-963 |
8-992 |
•001376 |
861534 |
597 |
|
728 |
529,984 |
385,828,352 |
26-991 |
8-996 |
•001374 |
862131 |
596 |
|
729 |
531,441 |
387,420,489 |
27-000 |
9-000 |
•001372 |
862728 |
595 |
|
730 |
532,900 |
389,017,000 |
27-018 |
9-004 |
•001370 |
863323 |
594 |
|
731 |
534,361 |
390,617,891 |
27-037 |
9-008 |
•001368 |
863917 |
594 |
|
732 |
535,824 |
392,223,168 |
27-055 |
9-012 |
•001366 |
864511 |
593 |
|
733 |
537,289 |
393,832,837 |
27-074 |
9-016 |
•001364 |
865104 |
592 |
|
734 |
538,756 |
395,446,904 |
27-092 |
9-020 |
•001362 |
865696 |
591 |
|
735 |
540,225 |
397,065,375 |
27-111 |
9-023 |
•001361 |
866287 |
590 |
|
736 |
541,696 |
398,688,256 |
27-129 |
9-029 |
•001359 |
866878 |
589 |
|
737 |
543,169 |
400,315,553 |
27-148 |
9-033 |
•001357 |
867467 |
589 |
|
738 |
544,644 |
401,947,272 |
27-166 |
9-037 |
•001355 |
868056 |
588 |
|
739 |
546,121 |
403,583,419 |
27-184 |
9-041 |
•001353 |
898644 |
587 |
|
740 |
547,600 |
405,224,000 |
27-203 |
9-045 |
•001351 |
869232 |
586 |
|
741 |
549,081 |
406,869,021 |
27-221 |
9-049 |
•001350 |
869818 |
586 |
|
742 |
550,564 |
408,518,488 |
27-239 |
9-053 |
•001348 |
870404 |
585 |
|
743 |
552,049 |
410,172,407 |
27-258 |
9-057 |
•001346 |
870989 |
584 |
|
744 |
553,536 |
411,830,784 |
27-276 |
9-061 |
•001344 |
871573 |
583 |
|
745 |
555,025 |
413,493,625 |
27-295 |
9-065 |
•001342 |
872156 |
583 |
|
746 |
556,516 |
415,160.936 |
27-313 |
9-069 |
•001340 |
872739 |
582 |
|
747 |
558,009 |
416,832,723 |
27-331 |
9-073 |
•001339 |
873321 |
581 |
|
748 |
559,504 |
418,508,992 |
27-349 |
9-077 |
•001337 |
873902 |
580 |
|
749 |
561,001 |
420,189,749 |
27-368 |
9-081 |
•001335 |
874482 |
579 |
G.E.
IS
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
750 |
502,500 |
421,875,000 |
27-386 |
9-086 |
•001333 |
875061 |
579 |
|
751 |
564,001 |
423,564,751 |
27-404 |
9-089 |
•001332 |
875640 |
578 |
|
752 |
565,504 |
424,525,900 |
27-423 |
9-094 |
•C01330 |
876218 |
577 |
|
753 |
567,009 |
426,957,777 |
27-441 |
9-098 |
•001328 |
876795 |
576 |
|
754 |
568,516 |
428,661,064 |
27-459 |
9-102 |
•001326 |
877371 |
576 |
|
755 |
570,025 |
430,368,875 |
27-477 |
9-106 |
•001325 |
877947 |
575 |
|
756 |
571,536 |
432,081,216 |
27-495 |
9-109 |
•001323 |
878522 |
574 |
|
757 |
573,049 |
433,798,093 |
27-514 |
9-114 |
•001321 |
879096 |
573 |
|
758 |
574,564 |
435,519,512 |
27-532 |
9-118 |
•001319 |
879669 |
573 |
|
759 |
576,081 |
437,245,479 |
27-549 |
9-122 |
•001318 |
880242 |
572 |
|
760 |
577,600 |
438,976,000 |
27-568 |
9-126 |
•001316 |
880814 |
571 |
|
761 |
579,121 |
440,711,081 |
27-586 |
9-129 |
•001314 |
881385 |
570 |
|
762 |
580,644 |
442,450,728 |
27-604 |
9-134 |
•001312 |
881955 |
570 |
|
763 |
582,169 |
444,194,947 |
27-622 |
9-138 |
•001311 |
882525 |
569 |
|
764 |
583,696 |
445,943,744 |
27-640 |
9-142 |
•001309 |
883093 |
568 |
|
765 |
585,225 |
447,697,125 |
27-659 |
9-146 |
•001307 |
883661 |
567 |
|
766 |
586,756 |
449,455,096 |
27-677 |
9-149 |
•001305 |
884229 |
566 |
|
767 |
588,289 |
451,217,663 |
27-695 |
9-154 |
•001304 |
884795 |
566 |
|
768 |
589,824 |
452,984,832 |
27-713 |
9-158 |
•001302 |
885361 |
565 |
|
769 |
591,361 |
454,756,609 |
27-731 |
9-162 |
•001300 |
885926 |
565 |
|
770 |
592,900 |
456.533,000 |
27-749 |
9-166 |
•001299 |
886491 |
564 |
|
771 |
594,441 |
458^314,011 |
27-767 |
9-169 |
•001297 |
887054 |
563 |
|
772 |
595,984 |
460,099,648 |
27-785 |
9-173 |
•001295 |
887617 |
562 |
|
773 |
597,529 |
461,889,917 |
27-803 |
9-177 |
•001294 |
888179 |
562 |
|
7T4 |
599,076 |
463,684,824 |
27-821 |
9-181 |
•001292 |
888741 |
r><;i |
|
775 |
600,625 |
465,484,375 |
27-839 |
9-185 |
•001290 |
889302 |
560 |
|
776 |
602,176 |
467,288,576 |
27-857 |
9-189 |
•001289 |
889862 |
559 |
|
777 |
603,729 |
469,097,433 |
27-875 |
9-193 |
•001287 |
890421 |
559 |
|
778 |
605,284 |
470,910,952 |
27-893 |
9-197 |
•001285 |
890980 |
558 |
|
779 |
606,841 |
472,729,139 |
27-910 |
9-201 |
•001284 |
891537 |
558 |
|
780 |
608,400 |
474,552,000 |
27-928 |
9-205 |
•001282 |
892095 |
556 |
|
781 |
609,961 |
476,379,541 |
27-946 |
9-209 |
•001280 |
892651 |
556 |
|
782 |
611,524 |
478,211,768 |
27-964 |
9-213 |
•001279 |
893207 |
555 |
|
783 |
613,089 |
480,048,687 |
27-982 |
9-217 |
•001277 |
893762 |
554 |
|
784 |
614,656 |
481,890,304 |
28-000 |
9-221 |
•001276 |
894316 |
554 |
|
785 |
616,225 |
483,736,625 |
28-017 |
9-225 |
•001274 |
894870 |
553 |
|
786 |
617,796 |
485,587,656 |
28-036 |
9-229 |
•001272 |
895423 |
552 |
|
787 |
619,369 |
487,443,403 |
28-053 |
9-233 |
•001271 |
895975 |
551 |
|
788 |
620,944 |
489,303,872 |
28-071 |
9-237 |
•001269 |
896526 |
551 |
|
789 |
622,521 |
491,169,069 |
28-089 |
9-240 |
•001267 |
897077 |
550 |
|
790 |
624,100 |
493,039,000 |
28-107 |
9-244 |
•001266 |
897627 |
549 |
|
791 |
625,681 |
494,913,671 |
28-125 |
9-248 |
•001264 |
898176 |
549 |
|
792 |
627,624 |
496,793,088 |
28-142 |
9-252 |
•001263 |
898725 |
548 |
|
793 |
628,849 |
498,677,257 |
28-160 |
9-256 |
•001261 |
899273 |
547 |
|
794 |
630,436 |
500,566,184 |
28-178 |
9-260 |
•001259 |
899821 |
546 |
GENERAL MATHEMATICAL TABLES.
19
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
795 |
632,025 502,459,875 28'196 |
9-264 |
•001258 |
9003(57 |
546 |
||
|
796 |
633,616 |
504,358,336 28*213 |
9-268 |
•001256 |
900913 |
545 |
|
|
797 |
635,209 |
506,261,573 128-231 |
9-271 |
•001255 |
901458 |
545 |
|
|
798 |
636,804 |
508,169,592 J28-249 |
9-275 |
•001253 |
902003 |
544 |
|
|
799 |
638,401 |
510,082,399 |
28-266 |
9-279 |
•001251 |
902547 |
543 |
|
800 |
640,000 |
512,000,000 |
28-284 |
9-283 |
•001250 |
903090 |
542 |
|
801 |
641,601 |
513,922,401 |
28-302 |
9-287 |
•001248 |
903633 541 |
|
|
802 |
643.204 |
515,849,608 |
28-319 |
9-291 |
•001247 |
904174 ! 541 |
|
|
803 1 641,809 |
517,781,627 |
28-337 |
9-295 |
•001245 |
904716 : 540 |
||
|
804 |
646,416 |
519,718,464 |
28-355 |
9-299 |
•001244 |
905256 540 |
|
|
805 |
648,025 |
521,660,125 |
28-372 |
9-302 |
•001242 |
905796 |
539 |
|
806 |
649,636 |
523,606,616 |
28-390 |
9-306 |
•001241 |
906335 |
538 |
|
807 |
651,249 |
525,557,943 |
28-408 |
9-310 |
•001239 |
906874 |
537 |
|
808 |
652,864 |
527,514,112 |
28-425 |
9-314 |
•001238 |
907411 |
537 |
|
809 |
654,481 |
529,475,129 |
28-443 |
9-318 |
•001236 |
907949 |
536 |
|
810 |
656,100 |
531,441,000 |
28-460 |
9-321 |
•001235 |
908485 |
536 |
|
811 |
657,721 |
533,411,731 |
28-478 |
9-325 |
•001233 |
909021 |
535 |
|
812 |
659,344 |
535,387,328 |
28-496 |
9-329 |
•001232 |
909556 |
535 |
|
813 |
660,969 |
537,366,797 |
28-513 |
9-333 |
•001230 |
910091 |
534 |
|
814 |
662,596 |
539,353,144 |
28-531 |
9-337 |
•001229 |
910624 |
533 |
|
815 |
664,225 |
541,343,375 |
28-548 |
9-341 |
•001227 |
911158 |
533 |
|
816 |
665,856 |
543,338,496 |
28-566 |
9-345 |
•001225 |
911690 |
533 |
|
817 |
667,489 |
545,338,513 |
28-583 |
9-348 |
•001224 |
912220 |
532 |
|
818 |
669,124 |
547,343,432 |
28-601 |
9-352 |
•001222 |
912753 |
531 |
|
819 |
670,761 |
549,353,259 |
28-618 |
9-356 |
•001221 |
913284 |
530 |
|
820 |
672,400 |
551,368,000 |
28-636 |
9-360 |
•001220 |
913814 |
529 |
|
821 |
674,041 |
553,387,661 |
28-653 |
9-364 |
•001218 |
914343 |
529 |
|
822 |
675,684 |
555,412,248 |
28-670 |
9-367 |
•001217 |
914872 |
528 |
|
823 |
677,329 |
557,441,767 |
28-688 |
9-371 |
•001215 |
915400 |
527 |
|
824 |
678,976 |
559,476,224 |
28-705 |
9-375 |
•001214 |
915927 |
527 |
|
825 |
680,625 |
561,515,625 |
28-723 |
9-379 |
•001212 |
916454 |
526 |
|
826 |
682,276 |
563,559,976 |
28-740 |
9-383 |
•001211 |
916980 |
526 |
|
827 |
683,929 |
565,609,283 |
28-758 |
9-386 |
•001209 |
917506 |
525 |
|
828 |
685,584 |
567,663,552 |
28-775 |
9-390 |
•001208 |
918030 |
524 |
|
829 |
687,241 |
569,722,789 |
28-792 |
9-394 |
•001206 |
918555 |
523 |
|
830 |
688,900 |
571,787,000 |
28-810 |
9-398 |
•001205 |
919078 |
523 |
|
831 |
690,561 |
573,856,191 |
28-827 |
9-401 |
•001203 |
919601 |
522 |
|
832 |
692,224 |
575,930,368 |
28-844 |
9-405 |
•001202 |
920123 |
522 |
|
833 |
693,889 |
578,009,537 |
28-862 |
9-409 |
•001200 |
920645 |
521 |
|
834 |
695,556 |
580,093,704 |
28-879 |
9-413 |
•001199 |
921166 |
520 |
|
835 |
697,225 |
582,182,875 |
28-896 |
9-417 |
•001198 |
921686 |
520 |
|
836 |
698,896 |
584,277,056 |
28-914 |
9-420 |
•001196 |
922206 |
519 |
|
837 |
700,569 |
586,376,253 |
28-931 |
9-424 |
•001195 |
922725 |
519 |
|
838 |
702,244 |
588,480,472 |
28-948 |
9-428 |
•001193 |
923244 |
518 |
|
839 |
703,921 |
590,589,719 |
28-965 |
9-432 |
•001192 |
923762 |
517 |
C 2
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
840 |
705.600 |
592,704,000 |
28-983 9-435 |
•001190 |
924279 |
517 |
|
|
841 |
707.281 |
594,823,321 |
29-000 1 9-439 |
•001189 |
924796 |
516 |
|
|
842 |
708,964 |
596,947,688 |
29-017 |
9-443 |
•001188 |
925312 |
516 |
|
843 |
710,649 |
599,077,107 |
29-034 |
9-447 |
•001186 |
925828 |
515 |
|
844 |
712,836 |
601,211,584 |
29-052 |
9-450 |
•001185 |
926342 |
514 |
|
845 |
714,025 |
6031351,125 |
29-069 |
9-454 |
•001183 |
926857 |
513 |
|
846 |
715,716 |
605,495,736 |
29-086 |
9-458 |
•001182 |
927370 |
513 |
|
847 |
717.409 |
607,645,423 |
29-103 |
9-461 |
•001181 |
927883 |
513 |
|
848 |
719^104 |
609,800,192 |
29-120 |
9-465 |
•001179 |
928396 |
512 |
|
849 |
720,801 |
611,960,049 |
29-138 |
9-469 |
•001178 |
928908 |
511 |
|
850 |
722,500 |
614,125,000 |
29-155 |
9-473 |
•001176 |
929419 |
511 |
|
851 |
724,201 |
616,295,051 |
29-172 |
9-476 |
•001175 |
929930 |
510 |
|
852 |
725,904 |
618,470,208 |
29-189 |
9-480 |
•001174 |
930440 |
509 |
|
853 |
727,609 |
620,650,477 |
29-206 |
9-483 |
•001172 |
930949 |
509 |
|
854 |
729,316 |
622,835,864 |
29-223 |
9-487 |
•001171 |
931458 |
508 |
|
855 |
731,025 |
625,026,375 |
29-240 |
9-491 |
•001170 |
931966 |
508 |
|
856 |
732,736 |
627,222,016 |
29-257 |
9-495 |
•001168 |
932474 |
507 |
|
857 |
734,419 |
629,422,793 |
29-274 |
9-499 |
•001167 |
932981 |
506 |
|
858 |
736,164 |
631,628,712 |
29-292 |
9-502 |
•001166 |
933487 |
506 |
|
859 |
737,881 |
633,839,779 |
29-309 |
9-506 |
•001164 |
933993 |
505 |
|
860 |
739,600 |
636,056,000 |
29-326 |
9-509 |
•001163 |
934498 |
505 |
|
861 |
741.321 |
638.277,381 |
29-343 |
9-513 |
•001161 |
935003 |
504 |
|
862 |
743,044 |
640,503.928 |
29-360 |
9-517 |
•001160 |
935507 |
504 |
|
863 |
744,769 |
642,735,647 |
29-377 |
9-520 |
•001159 |
936011 |
503 |
|
864 |
746,496 |
644,972,544 |
29-394 |
9-524 |
•001157 |
936514 |
502 |
|
865 |
748,225 |
647.214,625 |
29-411 |
9-528 |
•001156 |
937016 |
502 |
|
866 |
749,956 |
649,461,896 |
29-428 |
9-532 |
•001155 |
937518 |
501 |
|
867 |
751,689 |
651,714,363 |
29-445 |
9-535 |
•001153 |
938019 |
501 |
|
868 |
753,42N4 |
653,972,032 |
29-462 |
9-539 |
•001152 |
938520 |
500 |
|
869 |
755,161 |
656,234,909 |
29-479 |
9-543 |
•001151 |
939020 |
499 |
|
870 |
756,900 |
658,503,000 |
29-496 |
9-546 |
•001149 |
939519 |
499 |
|
871 |
758,641 |
660,776,311 |
29-513 |
9-550 |
•001148 |
940018 |
498 |
|
872 |
760,384 |
663,054,848 |
29-529 |
9-554 |
•001147 |
940516 |
498 |
|
873 |
762,129 |
665,388,617 |
29-546 |
9-557 |
•001145 |
941014 |
497 |
|
874 |
763,876 |
667,627,624 |
29-563 |
9-561 |
•001144 |
941511 |
497 |
|
875 |
765,625 |
669,921,875 |
29-580 |
9-565 |
•001143 |
942008 |
496 |
|
876 |
767,376 |
672,221,376 |
29-597 |
9-568 |
•001142 |
942504 |
496 |
|
877 |
769,129 |
674,526,133 |
29-614 |
9-572 |
•001140 |
943000 |
495 |
|
878 |
770,884 |
676,836,152 |
29-631 |
9-575 |
•001139 |
943495 |
494 |
|
879 |
772,641 |
679,151,439 |
29-648 |
9-579 |
•001138 |
943989 |
494 |
|
880 |
774,400 |
681,472,000 |
29-665 |
9-583 |
•001136 |
944483 |
493 |
|
881 |
776,161 |
683,797,841 |
29-682 |
9-586 |
•001135 |
944976 |
493 |
|
882 |
777,924 |
686,1 28,966 |
29-698 |
9-590 |
•001134 |
945469 |
492 |
|
883 |
779,689 |
688,465,387 |
29-715 |
9-594 |
•001133 |
945961 |
491 |
|
884 |
781,456 |
690,807,104 |
29-732 |
9-597 |
•001131 |
946452 |
491 |
GENERAL MATHEMATICAL TABLES.
21
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
885 |
783,225 |
693,154,125 |
29-749 |
9-601 |
•001130 |
946943 |
490 |
|
886 |
784,996 |
695,506,456 |
29-766 |
9-604 |
•001129 |
947434 |
490 |
|
887 |
786,769 |
697,864,103 |
29-782 |
9-608 |
•001127 |
947924 |
489 |
|
888 |
788,544 |
700,227,072 |
29-799 |
9-612 |
•001126 |
948413 |
489 |
|
889 |
790,321 |
702,595,369 |
29-816 |
9-615 |
•001125 |
948902 |
488 |
|
890 |
792,100 |
704,969,000 |
29-833 |
9-619 |
•001124 |
949390 |
488 |
|
891 |
793,881 |
707,347,971 |
29-850 |
9-623 |
•001122 |
949878 |
487 |
|
892 |
795,664 |
709,732,288 |
29-866 |
9-626 |
•001121 |
950365 |
486 |
|
893 |
797,449 |
712,121,957 |
29-883 |
9-630 |
•001120 |
950851 |
486 |
|
894 |
799.236 |
714,516,984 |
29-900 |
9-633 |
•001119 |
951338 |
485 |
|
895 |
801,025 |
716,917,375 |
29-916 |
9-637 |
•001118 |
951823 |
485 |
|
896 |
802,816 |
719,323,136 |
29-933 |
9-640 |
•001116 |
952308 |
484 |
|
897 |
804,609 |
721,734,273 |
29-950 |
9-644 |
•001115 |
952792 |
484 |
|
898 |
806,404 |
724,150,792 |
29-967 |
9-648 |
•001114 |
953276 |
484 |
|
899 |
808,201 |
726,572,699 |
29-983 |
9-651 |
•001112 |
953760 |
483 |
|
900 |
810,000 |
729,000,000 |
30-000 |
9-655 |
•001111 |
954243 |
482 |
|
901 811,801 |
731,432,701 |
30-017 |
9-658 |
•001110 |
954725 |
482 |
|
|
902 813,604 |
733,870,808 |
30-033 |
9-662 |
•001109 |
955207 |
481 |
|
|
903 : 815,409 |
736,314,327 |
30-050 |
9-666 |
•001107 |
955688 |
480 |
|
|
904 |817,216 |
738,763,264 |
30-066 |
9-669 |
•001106 |
956168 |
480 |
|
|
905 i 819,025 |
741,217,625 |
30-083 |
9-673 |
•001105 |
956649 |
479 |
|
|
906 ! 820,836 |
743,677,416 |
30-100 |
9-676 |
•001104 |
957128 |
479 |
|
|
907 : 822,649 |
746.142,643 |
30-116 |
9-680 |
•001103 |
957604 |
478 |
|
|
908 ! 824,464 |
748,613,312 |
30-133 |
9-683 |
•001101 |
958086 |
478 |
|
|
909 |
826,281 |
751,089,429 |
30-150 |
9-687 |
•001100 |
958564 |
477 |
|
910 |
828,100 |
753,571,000 |
30-163 |
9-690 |
•001099 |
959041 |
477 |
|
911 |
829,121 |
756,058,031 |
30-183 |
9-694 |
•001098 |
959518 |
477 |
|
912 |
831,744 |
758.550,528 |
30-199 |
9-698 |
•001096 |
959995 |
476 |
|
913 |
833,569 |
761,048,497 |
30-216 |
9-701 |
•001095 |
960471 |
475 |
|
914 |
835.396 |
763,551,944 |
30-232 |
9-705 |
•001094 |
960946 |
475 |
|
915 |
837,225 |
766,060,875 |
30-249 |
9-708 |
•001093 |
961421 |
474 |
|
916 839,056 |
768,575,296 |
30-265 |
9-712 |
•001092 |
961895 |
474 |
|
|
917 810,889 |
771,095,213 |
30-282 |
9-715 |
•001091 |
962363 |
474 |
|
|
918 842,724 |
773,620,632 |
30-298 |
9-718 |
•001089 |
962843 |
473 |
|
|
919 844,561 |
776,151,559 |
30-315 |
9-722 |
•001088 |
963316 |
473 |
|
|
920 : 846,400 |
778,688,000 |
30-331 |
9-726 |
•001087 |
963788 |
472 |
|
|
921 j 848,241 |
781,229,961 |
30-348 |
9-729 |
•001086 |
964260 |
471 |
|
|
922 |
850,084 |
783,777,448 |
30-364 |
9-733 |
•001085 |
964731 |
471 |
|
923 |
851,929 |
786,330,467 |
30-381 |
9-736 |
•001083 |
965202 |
470 |
|
924 853,776 |
788,889,024 |
30-397 |
9-740 |
•001082 |
965672 |
470 |
|
|
925 855,625 |
791,453,125 |
30-414 |
9-743 |
•001081 |
966142 |
469 |
|
|
926 i 857,476 |
794,022,776 |
30-430 |
9-747 |
•001080 |
966611 |
469 |
|
|
927 859,329 |
796,597,983 |
30-447 |
9-750 |
•001079 |
967080 |
468 |
|
|
928 861,184 |
799,178,752 |
30-463 |
9-754 |
•001078 |
967548 |
468 |
|
|
929 863,041 |
801,765,089 |
30-479 |
9-757 |
•001076 |
968016 |
467 |
GAS ENGINEER'S POCKET-BOOK.
|
No. |
Square. |
Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
930 |
864.900 |
804,357,000 |
30-496 |
9-761 |
•001075 |
968483 |
467 |
|
931 |
866,761 |
806,954,491 |
30-512 |
9-764 |
•001074 |
968950 |
466 |
|
932 |
868,624 |
809,557,568 |
30-529 |
9-768 |
•001073 |
969416 |
466 |
|
933 |
870,489 |
812,166.237 |
30-545 |
9-771 |
•001072 |
969882 |
465 |
|
934 |
872,356 |
814,780,504 |
30-561 |
9-775 |
•001071 |
970347 |
465 |
|
935 |
"874,225 |
817,400,375 |
30-578 |
9-778 |
•001070 |
970812 |
464 |
|
936 |
876,096 |
820,025,856 |
30-594 |
9-783 |
•001068 |
971276 |
464 |
|
937 |
877,969 |
822,656,953 |
30-610 |
9-785 |
•001067 |
971740 |
463 |
|
938 |
879,844 |
825,293,672 |
30-627 |
9-789 |
•001066 |
972203 |
463 |
|
939 |
881,721 |
827,936.019 |
30-643 |
9-792 |
•001065 |
972666 |
462 |
|
940 |
883,600 |
830,584,000 |
30-659 |
9-796 |
•001064 |
973128 |
462 |
|
941 |
885,481 |
833,237,621 |
30-676 |
9-799 |
•001063 |
973590 |
461 |
|
942 |
887,364 |
835,896,888 |
30-692 |
9-803 |
•001062 |
974051 |
461 |
|
943 |
889,249 |
838,561.807 |
30-708 |
9-806 |
•001060 |
974512 |
460 |
|
944 |
891,136 |
841.232,284 |
30-724 |
9-810 |
•001059 |
974972 |
460 |
|
945 |
893,025 |
843,908,625 |
30-741 |
9-813 |
•001058 |
975432 |
459 |
|
946 |
894,916 |
846,590,536 |
30-757 |
9-817 |
•001057 |
975891 |
459 |
|
947 |
896.809 |
849,278,123 |
30-773 |
9-820 |
•001056 |
976350 |
458 |
|
948 |
898^704 |
851,971.392 |
30-790 |
9-823 |
•001055 |
976808 |
458 |
|
949 |
900,601 |
854,670,349 |
30-806 |
9-827 |
•001054 |
977266 |
457 |
|
950 |
902,500 |
857,375,000 |
30-822 |
9-830 |
•001053 |
977724 |
457 |
|
951 |
904,401 |
860,085,351 |
30-838 |
9-834 |
•001052 |
978181 |
456 |
|
952 |
906.304 |
862,801,408 |
30-854 |
9-837 |
•001050 |
978637 |
456 |
|
953 |
908,209 |
865,523,177 |
30-871 |
9-841 |
•001049 |
979093 |
455 |
|
954 |
910,116 |
868,250,664 |
30-887 |
9-844 |
•001048 |
979548 |
455 |
|
955 |
912,025 |
870,983,875 |
30-903 |
9-848 |
•001047 |
980003 |
455 |
|
956 |
913,936 |
873,722,816 |
30-919 |
9-851 |
•001046 |
980458 |
454 |
|
957 |
915,849 |
876,467.493 |
30-935 |
9-854 |
•001045 |
980912 |
454 |
|
958 |
917,764 |
879,217^12 |
30-951 |
9-858 |
•001044 |
981366 |
453 |
|
959 |
919,681 |
881,974,079 |
30-968 |
9-861 |
•001043 |
981819 |
452 |
|
960 |
921,600 |
884,736,000 |
30-984 |
9-865 |
•001042 |
982271 |
452 |
|
961 |
923,521 |
887,503,681 |
31-000 |
9-868 |
•001041 |
982723 |
452 |
|
962 |
925,444 |
890,277,128 |
31-016 |
9-872 |
•001040 |
983175 |
451 |
|
963 |
927,369 |
893,056,347 |
31-032 |
9-875 |
•001038 |
983626 |
451 |
|
964 |
929,296 |
895,841,344 |
31-048 |
9-878 |
•001037 |
984077 |
450 |
|
965 |
931,225 |
898,632,125 |
31-064 |
9-881 |
•001036 |
984527 |
450 |
|
QRR yoo |
933,156 |
901,428,696 |
31-080 |
9-885 |
•001035 |
984977 |
449 |
|
967 |
935,089 |
904,231,063 |
31-097 |
9-889 |
•001034 |
985426 |
449 |
|
968 |
937,024 |
907,039,232 |
31-113 |
9-892 |
•001033 |
985875 |
449 |
|
969 |
938,961 |
909,853,209 |
31-129 |
9-895 |
•001032 |
986324 |
448 |
|
970 |
940,900 |
912,673,000 |
31-145 |
9-899 |
•001031 |
986772 |
447 |
|
971 |
942,841 |
915,498,611 |
31-161 |
9-902 |
•001030 |
987219 |
447 |
|
972 |
944,784 |
918,330.048 |
31-177 |
9-906 |
•001029 |
987666 |
447 |
|
973 |
946,729 |
921,167,317 |
31-193 |
9-909 |
•001028 |
988113 |
446 |
|
974 |
948,676 |
924,010,424 |
31-209 |
9-912 |
•001027 |
988559 |
446 |
GENERAL MATHEMATICAL TABLES.
|
No. |
Square. |
: Cube. |
Square Root. |
Cube Root. |
Recip- rocal. |
Loga- rithm. |
Differ- ence. |
|
975 |
950,625 |
926,859,375 |
31-225 |
9-916 |
•001026 |
989005 |
445 |
|
976 |
952.576 |
929.714,176 |
31-241 |
9-919 |
•001025 |
989450 |
445 |
|
977 |
954,529 |
932,574,833 |
31-257 |
9-923 |
•001024 |
989895 |
444 |
|
978 956,484 |
935,441,352 |
31-273 |
9-926 |
•001022 |
990339 |
444 |
|
|
979 958,441 |
938,313,739 |
31-289 |
9-929 |
•001021 |
990783 |
443 |
|
|
980 900,400 |
941,192,000 |
31-305 |
9-933 |
•001020 |
991226 |
443 |
|
|
981 962.361 |
944,076,141 |
31-321 |
9-936 |
•001019 |
9916-69 |
442 |
|
|
982 964,324 |
946,966,168 |
31-337 |
9-940 |
•001018 |
992111 |
442 |
|
|
983 966,289 |
949,862,087 |
31-353 |
9-943 |
•001017 |
992554 |
441 |
|
|
984 968,256 |
952,763,904 |
31-369 |
9'946 |
•001016 |
992995 |
441 |
|
|
985, 970,225 |
955,671,625 |
31-385 |
9-950 |
•001015 |
993436 |
441 |
|
|
986! 972.196 |
958,585,256 |
31-401 |
9-953 |
•001014 |
993877 |
440 |
|
|
987 |
974,169 |
961,504.803 |
31-416 |
9-956 |
•001013 |
994317 |
440 |
|
988 |
976,144 |
964,430^272 |
31-432 |
9-960 |
•001012 |
994757 |
439 |
|
989 |
978,121 |
967,361,669 |
31-448 |
9-963 |
•001011 |
995196 |
439 |
|
990 |
980,100 |
970,299,000 |
31-464 |
9-966 |
•001010 |
995635 |
439 |
|
991 |
982,081 |
973,242.271 |
31-480 |
9-970 |
•001009 |
996074 |
438 |
|
992; 984.064 |
976,191,488 |
31-496 |
9-973 |
•001008 |
996512 |
437 |
|
|
993 |
986,049 |
979,146,657 |
31-512 |
9:977 |
•001007 |
996949 |
437 |
|
994 |
988,036 |
982.107,784 |
31-528 |
9-980 |
•001006 |
997386 |
437 |
|
995 |
990,025 |
985,074.875 |
31-544 |
9-983 |
•001005 |
997823 |
436 |
|
996 |
992,016 |
988,047.936 |
31-559 |
9-987 |
•001004 |
998259 |
436 |
|
997 |
994,009 |
99l!026i973 |
31-575 |
9-990 |
•001003 |
998695 |
435 |
|
998 |
996,004 |
994,011,992 |
31-591 |
9-993 |
•001002 |
999131 |
434 |
|
QQQ you |
998,001 |
997,002,999 |
31-607 |
9-997 |
•001001 |
999565 |
|
|
1000 |
1,000,0001,000,000,000 |
31-623 |
10-000 |
•001000 |
The common Logarithm of any number is the power to which, if 10 be raised, the said number is the result thus :—
102 ss 100 therefore Log. = 2' ID2-** = 263 „ „ = 2-42
10-2.42 _ >0263 =2-42
GAS ENGINEER'S POCKET-BOOK. Areas and Circumferences of Circles.
BO t> C* O CO «Q Ok »O iQ 00 «P Ql t» ** A fc> O O CO 94 C4 IQ CO OS
3 I- OS C rH W M -* tO t- O C5 O (M >S IS CT GO C5 O C^l CO -H Iti »O
cs o o o o rH i M i-i <i
^ i-l <M C^ C^ <M C^ M (M (M C<}
-c
B d <X' CO i-H •* »O i-H — t^ O OC CC C5 JC O CO N « QO W •'*» t- »O O g ^ft CO b« OO O> O 64 A ^< CD -CD b> A O Od CO U) CiD (•• O O rH 9^ O9
-tlC5iO(M-tlt^-COC<)COt^C<imiC'^H'^IH^Ci-ti'1* O (N «S lr- C5 O r^l «> O r-t Cp IS b- O CO >p t- C5 O
M tQ t* tO »-4 OP CO O>f-4 O» C4 *« CO QO CO 00 £4 O) <0 f-t C4 i-4
-I|M Ht «!» HN <i» «!•* H«
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AREAS AND CIRCUMFERENCES OF CIRCLES. 25
26
GAS ENGINEERS POCKET-BOOK.
S O t- 'M CS M CC Ci is IS GC iS <M t -- f Ci t^ O O O <N ?t IS JC C5
N t t- 1- cs o 1+ e H-«S w i> os e« e* to i < - s o * <N o*
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b- 50 O » C3 t> GO 5O
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AREAS AND CIRCUMFERENCES OF CIRCLES.
27
10 «o t» oo o i^ oo T»t 10 ip cc o TH w 05 TH « b- op o «H
ft Ci O^ Oi 05 05 O5 O O O O O O O i"H »""* i—l r*4 I—*. i—* T-H r-H i-H r-
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nH O Cl b- -rH b- 00 CO Ci O5 C<« O
28
GAS ENGINEER'S POCKET-BOOK.
Hr-l t» C4 0» M CO 0» «g kQ 00 CO r-l GO <« 0> CO O O CO iH C* *Q CO 0) g i—l CO ^4 ^< CO l> 00 ^ PH £) CO '^jH CO ^b O) O ff4 CO ^t CO t~ CO 0} O)
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t-H i-l <N <M <M iM (>) <N 1C CO 1C CO CO •* •* -+H T*I -* -t< 11 IS >~ >S »S
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AREAS AND CIRCUMFERENCES OF CIRCLES.
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GAS ENGINEERS POCKET-BOOK.
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GAS ENGINEER'S POCKET-BOOK.
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AREAS AND CIRCUMFERENCES OF CIRCLES.
33
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AREAS AND CIRCUMFERENCES OF CIRCLES. 35
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38
GAS ENGINEER'S POCKET-BOOK.
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40
GAS ENGINEERS TOCKET-BOOK.
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PROPERTIES OF THE CIRCLE.
41
To find Area of a Segment of a Circle. — R'rom the area of a sector having same arc subtract the area of triangle whose 2 sides = radius of circle and base = chord of segment.
The volume of a sphere = diameter 3 X '5236.
Area of oval = major diameter X minor diameter X '7854.
To find the Length of a Side, the diameter being given : —
For a Hexagon, multiply the diameter by '577 Octagon, „ „ „ „ '414
,. '325
Decagon, Dodecagon, „
•2(58
The square of any number containing a fraction equals the whole number multiplied by its next higher digit + the square of the fraction, as follows : —
(802=8 X 9 + J
Properties of the Circle.
Circumference = diameter X 3-1416 or 3i. Diameter x '88(52 = side of equal square. Diameter x '7071 = „ inscribed square. Diameter2 X "7854 = area of circle. Length of arc of circle = no. of degrees X '01 7453.
42 GAS ENGINEER'S POCKET-BOOK.
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44 GAS ENGINEER'S POCKET-BOOK.
Square yards X '000000323 = square miles,
Acres * X -0015625 = ., .,
27,878,400 square feet = 1 ., '.,
3,097,600 square yards = 1 '.. .,
640 acres * = 1 !, i,
2-471143 „ = 1 hectare.
1 „ =10 square chains.
1 chain wide = 8 acres per mile.
Cubic Measure.
inches. feet. yards. cubic metres.
1 = -0005788 = -00002144 = -00001638(5 1.728= 1 = -03704 =-028315
46,656 = 27 =1 = -764513
Ale and Beer Measure (used for ammoniacal liquor), gills.
4 = 1 pint. 8 = 2 = 1 quart. 32 = 8 = 4 = 1 gallon. 288 = 72 = 36 = 9=1 firkin. 576 = 144= 72= 18= 2 = 1 kilderkin. 1.152 = 288 = 144= 36= 4 = 2 = 1 barrel. 1,728 = 432 = 216 = 54 = 6 = 3 = 1 -5 = 1 hogshead. 2.304 = 576 = 288 = 72 = 8 = 4 = 2 = r:'l = 1 puncheon. 3,356 = 864 = 432 = 108 = 12 = 6 = 3 =2 = 1'5 = 1 butt.
Measures of Capacity, or Dry Measure.
pints, galls. ]>ecks. bushels, quarters, weys. last. cubic1 feet. litres.
1- -125= -0025 = -01562= '00195= '00039= '000195= '020051= '5079
8=1 = -5 = -125 = '015(5 = -00312= '00150 = -10046 = 4'543
16= 2 =1 = -25 = '03125= '00025= '00312 = '32092 = 9'087
64 =8 = 4 =1 = '125 = '025 = '0125 = 1 '28307 = 30-34700
512= 64 =32 =8 =1 = '2 = '1 = 10'209 = 290'781
2560=3201 =100 = 40 = 5 =1 = '5 = 51-347 =1453-900
5120 = 640' =320 =80 =10 =2 =1 =102-09 =2907 'SI
Cubic inches X '028848 = pints. „ „ X -014424 = quarts.
'„ „ X -003606 = gallons.
„ „ X -0004508 = bushels. „ „ X -00005635 = quarters.
1 pint = 34-66 cubic inches.
1 gallon = 277-27384 cubic inches = 10 Ibs. distilled water.
Cubic feet X 6-2355 = gallons.
Cubic inches X '003607 = " .. Cubic feet x '78 = bushels. Cubic inches X -00045 = „
DECIMALS OF <£l STERLING.
45
Decimals of £1 Sterling.
|
Pence and |
*I. |
jdL |
||||
|
Shillings. |
Id. |
|||||
|
0 |
•0010416 |
•002083 |
•003125 |
|||
|
1 |
•00416 |
•0052083 |
•00625 |
•007291-6 |
||
|
2 |
•0083 |
•009375 |
•010416 |
•0114583 |
||
|
3 |
•0125 |
•0135416 |
•014583 |
' -015625 |
||
|
4 |
•016 |
•0177083 |
•01875 |
•0197916 |
||
|
5 |
•02083 |
•021875 |
•022916 |
•0239583 |
||
|
6 |
•025 |
•026416 |
•027083 |
•028125 |
||
|
7 |
•02910 |
•0302083 |
•03125 |
•0322916 |
||
|
8 |
•03 |
•034375 |
•035416 |
•0364583 |
||
|
9 |
•0375 |
•0385416 |
•039583 |
•040625 |
||
|
10 |
•0416 |
•0427083 |
•04375 |
•0447916 |
||
|
11 |
•04583 |
•046875 |
•047916 |
•0489583 |
||
|
1-0 |
•05 |
•0510416 |
•0520S3 |
•053125 |
||
|
1-1 |
•05416 |
•0552083 |
•05(525 |
•0572916 |
||
|
1-2 |
•0583 |
•059375 |
•060416 |
•0614583 |
||
|
1-8 |
•0625 |
•0635416 |
•064583 |
•065625 |
||
|
1-1 |
•06 |
•0677083 |
•06875 |
•0697916 |
||
|
1-5 |
•07083 ' |
•071875 • |
•072916 |
•0739583 |
||
|
W |
•075 |
•0760416 |
•077083 |
•078125 |
||
|
1-7 |
•07916 |
•0802083 ' |
•08125 |
•0822916 |
||
|
1-8 |
•083 |
•OS4375 |
•085416 |
•0864583 |
||
|
1-9 |
•0875 |
•0885416 |
•089583 |
•090625 |
||
|
1-10 |
•0916 |
•0927083 |
•09375 |
•0947916 |
||
|
Ml |
•09583 |
•096875 |
•097916 |
•0989583 |
||
|
2-0 |
•1 |
8-0 |
•4 |
14-0 '7 |
||
|
3-0 |
•15 |
9'0 |
•45 |
15-0 -75 |
||
|
4-0 |
•2 |
10-0 |
•5 |
16-0 -8 |
||
|
5-0 |
•25 |
11-0 |
•55 |
17-0 -85 |
||
|
o-o |
•3 |
12-0 |
•6 |
18-0 -9 |
||
|
7-0 |
•35 |
13-0 |
•65 |
19-0 -95 ' |
To Convert £ s. d. into Decimals of £1 by Inspection (approxi- mately).—I lace the £'s before the decimal point ; in the first place, after the decimal point, insert the florins or half the even number of shillings ; fill the second and third places with the number of farthings in any odd shilling, pence, and farthings, adding thereto 1 if the number of farthings be 24, 2 if 48, and 3 if 72 or more (the number of farthings can never amount to 96, because 96 farthings = 2/- = 'l).
By this rule the error cannot amount to 1 farthing.
GAS ENGINEER'S POCKET-BOOK.
Decimals of 1 Cwt.
|
Qrs. |
Qrs. |
Qrs. |
||||
|
0 |
1 |
2 |
3 |
|||
|
0 |
•25 |
•5 |
•75 |
|||
|
1 |
•008928 |
•258928 |
•508928 |
•758928 |
||
|
2, |
•017857 |
•267857 |
•517857 |
•767857 |
||
|
3 |
•026786 |
•276786 |
•52( |
5786 |
•776786 |
|
|
4 |
•035714 |
•285714 |
•535714 |
•785714 |
||
|
5 |
•044643 |
•294643 |
•544643 |
•794643 |
||
|
6 |
•053571 |
•303571 |
•553571 |
•803571 |
||
|
7 |
•0625 |
•3125 |
•5625 |
•8125 |
||
|
8 |
•071458 |
•321458 |
•571458 |
•821458 |
||
|
9 |
•080357 |
•330357 |
•580357 |
•830357 |
||
|
10 |
•089286 |
•339286 |
•589286 |
•839286 |
||
|
11 |
•098214 |
•348214 |
•598214 |
•848214 |
||
|
12 |
•107143 |
•357143 |
•607143 |
•857143 |
||
|
13 |
•116071 |
•366071 |
•616071 |
•866071 |
||
|
14 |
•125 |
•375 |
•625 |
•875 |
||
|
15 |
•133928 |
•383928 |
•633928 |
•883928 |
||
|
16 |
•142856 |
•392856 |
•642856 |
•892856 |
||
|
17 |
•151785 |
•401785 |
•651785 |
•901785 |
||
|
18 |
•160714 |
•410714 |
•660714 |
•910714 |
||
|
19 |
•169643 |
•419643 |
•669643 |
•919643 |
||
|
20 |
•178572 |
•428572 |
•678572 |
•928572 |
||
|
21 |
•1875 |
•4375 |
•6875 |
•9375 |
||
|
22 |
•196428 |
•446428 |
•696428 |
•946428 |
||
|
23 |
•205357 |
•455357 |
•705357 |
•955357 |
||
|
24 |
•214286 |
•464286 |
•714286 |
•964286 |
||
|
25 |
•223214 |
•473214 |
•723214 |
•973214 |
||
|
26 |
•232143 |
•482143 |
•732143 |
•982143 |
||
|
27 |
•241071 |
•491071 |
•741071 |
•991071 |
||
|
Ozs. |
Ozs. |
Ozs. |
||||
|
1 |
•000558 |
7 |
•003906 |
13 -007254 |
||
|
2 |
•001116 |
8 |
•004464 |
14 -007812 |
||
|
3 |
•001674 |
9 |
•005023 |
15 -008370 |
||
|
4 |
•002232 |
10 |
•005580 |
i -000139 |
||
|
5 |
•002790 |
11 |
•006138 |
$ -000279 |
||
|
6 |
•003348 |
12 |
•006696 |
f -000418 |
DECIMAL EQUIVALENTS. Decimals of 1 Mile.
|
500 yards 400 „ |
•284091 •227222 |
20 yards 10 , |
•011364 •005682 |
1 foot 11 inches |
•0001894 •000174 |
|
300 „ |
•170454 |
9 , |
•005114 |
10 ,, |
•000158 ' |
|
200 „ |
•113036 |
8 , |
•004545 |
9 „ |
•000142 |
|
100 „ |
•056818 |
7 , |
•003977 |
8 |
•000126 |
|
90 ., |
•051136 |
6 , |
•003409 |
7 , |
•000111 |
|
80 „ |
•045454 |
5 , |
•002841 |
6 |
•000095 |
|
70 „ |
•039773 |
•002273 |
5 |
•000079 |
|
|
60 „ |
•034091 |
3 I |
•001704 |
4 , |
•000063 |
|
50 „ |
•028409 |
2 |
•001136 |
3 '. |
•000047 |
|
40 ., |
•022727 |
I |
•000568 |
2 ;, |
•000032 |
|
30 ;. |
•017045 |
2 feet |
•000379 |
1 M |
•000016 |
Decimals of 1 Year of 365 Days.
|
300 days |
•821918 |
9 davs |
•024657 |
9 hours |
•001026 |
|
200 „ |
•547945 |
s .; |
•021918 |
8 , |
•000912 |
|
100 „ |
•273975 |
7 ., |
•019178 |
7 , |
•000798 |
|
90 „ |
•246575 |
5 " |
•016438 |
6 , |
•000684 |
|
80 „ |
•219178 |
5 ., |
•013698 |
5 .'. |
•000576 |
|
70 „ |
•191781 |
4 „ |
•010959 |
4 ; |
•000456 |
|
60 „ |
•164383 |
3 » |
•008219 |
3 ; |
•000342 |
|
50 i, |
•136986 |
2 M |
•005479 |
2 „ |
•000228 |
|
40 ;, |
•109589 |
•002739 |
i ;, |
•000114 |
|
|
30 ., |
•082192 |
12 hours |
•001369 |
i „ |
•000085 |
|
20 „ |
•054794 |
11 ., |
•001254 |
*„ |
•000057 |
|
10 ,. |
•027397 |
10 ., |
•001140 |
4 •» |
•000028 |
Decimal Equivalents of an Inch.
|
* |
•015625 |
ii |
•34375 |
i |
•671875 |
|
i |
•03125 |
8 |
•359375 |
ti |
•6875 |
|
i A |
•046875 |
, I |
•375 |
sf |
•703125 |
|
* |
•0625 |
if |
•390625 |
i |
•71875 |
|
& , |
•078125 |
3a |
•40625 |
II |
•734375 |
|
•09375 |
§7i |
•421875 |
1 |
•75 |
|
|
Si |
•109375 |
i7o |
•4375 |
si |
•765625 |
|
1 |
•125 |
5l |
•453 12» |
11 |
•78125 |
|
0°5 |
•140625 |
M |
•46875 |
55 |
•796875 |
|
& |
•15625 V |
ol |
•484375 |
ft |
•8125 |
|
u |
•171875 |
i |
•5 |
ST |
•828125 |
|
3 Ta |
•1875 |
$ |
•515625 |
I |
•84375 |
|
B |
•203125 |
ta |
•53125 |
§1 |
•859375 |
|
7 32 |
•21875 |
if |
•546875 |
| |
•875 |
|
ft |
•234375 |
i9s |
•5625 |
fl |
•890625 |
|
i |
•25 |
S7 R |
•578125 |
il |
•90625 |
|
' 1Z t)4 |
•265625 |
si |
•59375 |
of |
•921875 |
|
i |
•28125 |
§f |
•609475 |
y |
•9375 |
|
-5! |
•296875 |
i |
-.625 |
i |
•953125 |
|
A |
•3125 |
04l |
•640625 |
i |
•96875 |
|
B |
•328125 |
11 |
•65625 |
03 M |
•984375 |
48
GAS ENGINEERS POCKET-BOOK,
Inches and Fractions of Inches in Decimals of 1 foot.
|
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 11 |
|
|
0 |
•oooo |
•0833 |
•1667 '2500 |
•3333 |
•4167 |
•5000 |
•5833 |
•6667 |
<:7500 |
•8333 '9167 |
|
|
& |
•00-2(5 |
•0859 • |
•1693 |
•2526 |
•3359 -4198- |
•5026 |
•5859 |
•6693 |
•7526 |
•8359 '9193 |
|
|
TV |
•Oo;>2 |
•0885 |
•1719 |
•2552 '3385 |
•4219 |
•5052 |
•5885 |
•6719 |
•7552 |
•8385 '9219 |
|
|
« |
•0078 |
•0911 |
•1745 |
•2578 '3411 |
•4245 |
•5078 |
•5911 |
•6745 |
•7578 |
•8411 ,'9245 |
|
|
1 |
•0104 |
•0938 |
•1771 |
•2604 ! '3438 |
•4271 |
•5104 |
•5938 |
•6771 |
•7604 |
•8438 '-9271 |
|
|
& |
•0130 |
•0964 |
•1797 |
•2630 '34(54 |
•4297 |
•5130 |
•5964 |
•6797 |
•7630 |
•84(>4 -9297 |
|
|
A |
•015(5 |
•0990 |
•1823 |
•2656 ' '3490 |
•4323 |
•5156 |
•5990 |
•6823 |
•7656 |
•8490: "9323 |
|
|
T X |
•0182 |
•1016 |
•1849 |
•2682 |
•3516 |
•4349 |
•5182 -6016 |
•6849 |
•7682 |
•8516-9349 |
|
|
32 £ |
•0208 |
•1042 |
•1875 |
•2708 |
•3542 |
•4375 |
•5208 -6042 |
•6875 |
•7708 |
•8542 ,-9375 |
|
|
39o |
•02:54 |
•1068 |
•1901 |
"2734 |
•3568 |
•4401 |
•5234 -6068 |
•6901 |
•7734 |
•8568 i '9401 |
|
|
" TO |
•0260 |
•1094 |'1927 |
•2760 |
•3594 |
•4427 |
•5260 i -6094 |
•6927 |
•7760 |
•8594 I -9427 |
||
|
u |
•0286 |
•1120 |
•1953 -2786 |
•3620 |
•4453 |
•5286 :6120 |
•6953 |
•7786 |
•8620' '9453 |
||
|
1 |
•0313 |
•1146 |
•1117!' -2S13 |
•3646 |
•4479 |
•5313 | -614(5 |
•6979 |
•7813 |
•8646, '9479 |
||
|
11 7 |
•0339 |
•1172 |
•2005 '2839 |
•3672 |
•4505 |
•5,339 -6172 |
•7005 |
•7839 |
•8672 , -9505 |
||
|
To |
•03(55 |
•1198 |
•2031 |
•2865 |
•3698 |
•4531 |
•5365 |
•6198 |
•7031 |
•7865' |
•8698 '• -9531 |
|
U |
•0391 |
•1224 |
•2057 |
•2891 |
•3724 |
•4557 |
•5391 |
•6224 |
•7057 |
•7891 |
•8724 -9557 |
|
t |
•0417 |
•1250 |
•2083 |
•2917 |
•3750 |
•4583 |
•5417 |
•6250 |
•7083 |
•7917 |
•8750 '9583 |
|
H |
•0443 |
•1276 |
•2109 |
•2943 |
•3776 |
•4609 |
•5443 |
•6276 |
•7109 |
•7943 |
•8776 ! -9609 |
|
A |
•04(59 |
•1302 |
•2135 |
•2969 |
•3802 |
•4(535 |
•5469 |
•6302 |
•7135 |
•7969 |
•8802 -9635 |
|
11 |
•0495 |
•1328 |
•2161 |
•2995 |
•3828 |
'4661 |
•5495 |
•6328 |
•7161 |
•7995 |
•8828 -9661 |
|
1 |
•0521 |
•1354 |
•2188 |
•3021 |
•3854 |
•4(588 |
•5521 |
•6354 |
•7188 |
•8021 |
•8854 i -9688 |
|
5J |
•0547 |
•1380 |
•2214 |
•3047 |
•3880 |
•4714 |
•5547 |
•6380 |
•7214 |
•8047 |
•8880 1-9714 |
|
« |
•0573 |
•1406 |
•2240 |
•3073 |
•3U06 |
•4740 |
•5573 |
•6406 |
•7240 |
•8.073 |
•8906 -9740 |
|
If |
•0599 |
•1432 |
•2266 |
•3099 '3932 |
•4766 |
•5599 |
•6432 |
•7266 |
•8099 |
•8932 -9766 |
|
|
f |
•0(525 |
•1458 |
•2292 |
•31 •_'.-» -:w;..s |
•4792 |
•5625 |
•6458 |
•7292 |
•8125 |
•8958 i -9792 |
|
|
M |
•0651 |
•1484 |
•2318 |
•3151 '3984 |
•4818 |
•5651 |
•6484 |
•7318 |
•8151 |
•8984 j '9818 |
|
|
H |
•0677 |
•1510 |
•2344 -3177 '4010 |
•4844 |
•5677 |
•6510 |
7344 |
•8177 |
•9010 1-9844 |
||
|
** |
•0703 |
•1536 |
•2370 '3203 |
•4036 -4870 |
•5703 |
•6536 |
•7370 |
•8203 |
•9036-9870 |
||
|
1 |
•0729 |
•1563 |
•2396 ;-3229 -4063-4896 |
•5729 |
•6563 |
•7396 |
•8229 |
•9063 -9896. |
|||
|
If |
•0755 |
•1589 |
•2422 '3255* '4089 '4922 |
•5755 |
•6589 |
•7422 |
•8255 |
•9089 ,'9922 |
|||
|
« |
•0781 |
•1615 |
•2448 !'3281 '4115 '4948 |
•5781 |
•6615 |
•7448 |
•8281 |
•9115 ,-09-18 |
|||
|
»- |
•0807 |
•1641 |
•2474 |
•3307 I '4141 |
•4974 |
•5807 |
•6641. |
i* |
•8307 |
•9141 -9974 |
Ounces in Decimals of 1 Ib.
|
Ozs. |
'Lbs. |
Ozs. |
Lbs. |
Ozs. |
Lbs. |
|
i |
•015625 |
5 |
•3125 |
1<H |
•65625 |
|
i |
•03125 |
Bi |
•34375 |
11 |
•6875 |
|
|. |
•046875 |
6 |
•375 |
Hi |
•71875 |
|
1 |
•0625 |
*H |
•40625 |
12 |
•75 |
|
H |
•09375 |
7 |
•4375 |
12£ |
•78125 |
|
2 |
•125 , |
71 |
•46875 |
13 |
•8125 |
|
2i |
•15625 |
8 |
•5 |
13i |
•84375 |
|
3 |
•1875 |
8i |
•53125 |
14 |
•875 |
|
3 J |
•21875 |
9 |
•5625 |
Ui |
•90625 |
|
4 |
:25 |
% |
•59376 |
15 |
•9375 |
|
« |
•28125 |
10 |
•625 • |
IBi |
•9687 |
DECIMALS OF 1 TON. Decimals of 1 Ton.
•^CSCO ••* OO 00
O CO CO <N CO is T-( GO "* T- I OS -* »OOS-^OSCOOOCvll>-<MCerH«OOlO C^tDi— llSO-**OSIOCC<Nt-T— I SO O
OO>— li-H
•* CO CO t> <N «O
O-*OS OJO5CS
eOQO<Mt>»-l«>O
ii -^^'SiS^C^Ct-
CO CO GO GO GO CO CO CO CO CO CO GO GO GO
so so so so so so so so so so so so sc so sc so so t^* t*- t*» t^-
909999999909099999999
SCeOOSSOlNOOlSrHOO^+lr-lt-"* SOCO COC^COlSi-IGO'^rHCJ**
ooooooooooooooooooooooo
COCOCOICMCO^'ti-*i-
r— I i— IC<ICx1ICeO^-*'*l»SlS OOOOOOOOOOO
99099099990
i— I i— IC<I Or- (T-HI-HI-H-H
009999
50
GAS ENGINEER'S POCKET-BOOK.
CO «O OS CO 94 GOTO rH 00 **» ^ t» oj< O CC CC IN GO Ml rH GO -fw— I Ci -+i o}< OS CO OO CO to 941> rH CO rH 1Q O tO OS 0)4 OS CO OO 94 to C4 CO f— i CO O IQ M IS Ci CC CO IN t- i-i CC O IS Ci -f GO CC I- rH JC O iS Ci -* GO CC b- (M O i— i IS tofcooOcOCbOSOQi-lrHi-l9494COCO^'<HiOtQaQCOCOtotoGOaOOSOS
Ci Ci CiCiCiCiCiCiCiCiCiCiCiCi Ci Ci Ci Ci Ci Ci Ci Ci
C<1 <N <N <M IN tN <M 'M (N *N CV) cq <N 7q GN <N <N <N 1^4 (N <>i r>\
O O i— i i—( ^i ri cs cc cc ^ -t1 i's is 5 cc i^
COCOCOOOGOCOaOOOCOCOCOCOGOCOGOCO
IO
IS Ci CC GO (N t-^ i— I i O >S CS -f OO CC t~- i— I ^C O 1*S Ci -* GO CC l>- <N CC I-H IS CI IN CC CC -ti -f >S iS » CC CC l~~ 1-- GC OC Ci Ci O O O i— I i— I C<l ^ CC CC -t< -f
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0 ^GOCCl^C^tC^iSO^OCCCO^itb^-llSOo^OSCOOoStofMtOO
« ^-» r-4 i-H 94 (N CO CO ^* •* •* »O »O CO CO l> to OO 00 GO OS OS O Q i-C rH (N
CCCCCi«C'<NCOlS'-iaO-HrHt H CCCC ?CC<lQOlSi-ICO-tii— IC5-*
^ CI CC X CC t^ (M t^ ^-i -C i-H »O O M2.OS •* q> CO OO 94 to <N CO f-4 CO O «O w iSpCCCOlNl-r^OOlS l>» t>- GO CC Ci C
IN (N C<l M O
CCCCCS?C(NGOiSi— IGO^Hi— I t» -^ CCCC CCfNOOiCi-HGO-^i— (Ci oj( O^ CO OO-CO 1^ 94^ ^ CO rH. 1C O IO Ci -«ti Ci CC GO <N h- IN tC i— I CO O I CJ
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^^CCCO^I^^I>r4^rHlSOlSCi-JC^CCGO
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DECIMALS OP 1 TON.
COcOCiCO<MGO»arHCO-HrHt * O CO «T C<1 CO »C i— I CO -H rH Ci ^1
-* Ci CO CO CO b-- <M b- i— I CO r—t 1C O »C Ci -^ CS CO CO C-l b- <M ICJ i— I iD O 1C »C Ci CO CO C^ lr- f— ItOOiCCi-tlCOCOt-"— lOO»SOS^<GOcCb-C<ICCi— lid
«O CO «O<MGOlCrHGO^r-lCi'*l
M ^ QO c3 ^ C^ & rH IQ O ^ OS CO CO Gtt CO iH IQ O <** OS CO CO CSI b» rH CO O
** »OiCiCOCOb-t~-COCOCiCiCiOOrHr- I <M <M CO CC CO •* -tl 1C 1C ?O to b- <M <M <M C"J *>} rN C^l Ol <M 'M <M ?» CO TO CO CC CO TO CC 1C CO CO CO CO CO CO CO CO
CO
^ os co oo eb t» e» t> rH co i-t 10 o »a os •** os co co c* t~ c* co »H cc o »o
M <M CO CO -H -tl 1C 1C «S CO O b- b- CO CO Ci Ci O O O r— I rH Vl <M CO CO -H -tl r-* i— I rH i— I i— ( r— I i— I i— I i— i r- 1 i— I I-H r— ! rH i— I i— I rH (M (M O1 (M M <M O\ (M (>4 C-l OJ
C5 CO Ci CO iM CO »S i— ICOHHi— (b--*l tTCO O<MCOlC^HCO-^r— iCi-* -* Ci CO CO CO b- <M b- i-l iC ^H 1C O 1C Ci -H Ci CO CO <M r^ <M 'O r-l O O 1C H> OO CO b- O5 CO r-t 1O O •«** O> CO CO C9 CO rH »O O •* OS CO CO C^ b- f-l «O C
SoOO§OOOOOOOOOOOOc5oOOOrHi-t»HrHr3
CCcOOSCCOlCClSrHGO-*rHb--tl tCCO OC^lCOlCi— ICO-rHi— ! CS -+l -HCiCOCOCOb-C^Jt^r-iOr-llCOlOOS^.OSeOOOIMb-NeOr-ICOOlO »O OS CO CO O» b» |H CO O B> OS H4 CO CO l>- rH CO O U5 OS ^ 00 CO b- « CO rH »O
b-b-COCOCiCiOOr-4rHrHC»<NCOCO-*-tllCiCiC^^;i-~t:^COCOCiCi
COCOCJCSC-lCOlCi-HCOH^rHb-HH ?£CO CC (M GO >O r- 1 CO -^ <— I C5 -+l -tl Ci CO CO CO b- <M t^ rH CO rH 1C O 1C Ci -f Ci CO CO <M r^ 'M tC i— I «5 O 1C •«#CO»fc»<M<£T-tiCO-HCiCOCO'<ri?Ci~<iCO^OSCO<»e<lt>rHCOO
cpwcpotcpcocpcocpcpcocpcpcpcpcpcpcocpcpcpcpcocpcoc^
"*l Ci CO CO CO b- 1^5 b- r-l O i-^ 1C O »C Ci -f Ci CO CO <M t^ C<I CO rH .CO O »O 1C Ci CO CC (M b- .-I <£ O 1C Ci -tl CO' CO b- rH CC O 1C Ci -H CO1 CO 1^ <M '•£ rH 1C <M O-l CO CO HH HH 1C 1C <VO ?C CC l^- l>- CO CO Ci Ci O O O i— I i— I (N C-l CO CO -H -tl «OtO«OCO5OCO«OCOCOCOCOCOCOCOCOCp<Ob-b-b-b-t-b«b- 1^- b- b- l>-
cpcpcpcpcpcpcpcpcpcpcpcocpcocpcpcpcpcpcpcpcocpcocpcococo
Q «* CO CO t» CN-CO rH lO ^ -5n O» CO OO Ol CO rH 1C O -ti Ci CO C/D (M b-
O O f-lrH « CT CO CO •* -* ^»4 iQ iO CO tC t> t* CO GQ CO OS OS O O i-i r-, v.-,
cpcpcocpcpcocococpcocococpcpcocpcpcpcocpcpcpcoco
-+i Ci CO CO CO I- 7^ b^ i-l '•£ rH 1C O 1C Ci -ft Ci CO CO C-l l^ C^ tC r- 1 5 O 1C
gn 1C Ci CO CO C-l L- >— I — O 1C Ci -t-l CO CO l^- '-H tT O 1C Ci -+i CO CO b- (M ^O i— I 1C
cococpcpcpcpcpcpcpcpcpcpMcpcococpcpcpcocpcpcpcoc^
CSCOOSCC<MGC»Ci-HCOHHrHt * tTCO '-C'MCOlCr-IGO-^rHCi'+l
•>«4 O> CO CO CO t- « t» rH CO i-H O O »C O --H Ci CO CO (^ b- C^ O rH CO O ^
cococococpcpcpcpcpcocpcpcpcpcpcocpco co
«OSOCS^<NOOlOrHCO-+lrHr>"*l tOCO iO 0-1 CO 1C rH CO -H i— I Ci ^ -* Ci CO CO CO b- CN b- rH O rH «O Q »O O» •* OS CO CO CSI t- CH.CO rH CO O >O
1C Ci CO CO <M I— i— I ^O O 1C Ci -ti CO CO I"- i— I ^O O 1C Ci -tl CO CO b- C<) CO r- 1 1C
^p^rHrHrHrHi-trHrHrHiHiHrHrHiHrHrHC^C^e^e^eXICqC^C^eSICSie^
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p
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Q A 'cococococococococococpcocococococococpcococpcocpcpcococo
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52
GAS ENGINEER'S POCKET-BOOK.
ip ip ip in ip m in in in ip m in in in m in in >n in in m in in in in m in
«CCOCiCC<NOOinT-IOO-*i--ll.--'*l CC CO «C<MGCini-IGC^r-ICi-*
•«* os co ao co t» o* tvi-t to r-i *o © »o o> •**< es «o oo eM I><N «o »H «o o >o
r>-t-t-t-i>.i>.t-t>.t-t-i--t>-GcccGC<XGCGCccGcccGC<x><x>Gcco<XGC in m m in m in in in in m in m in m m in in »n m m m in in in in m >n m
CCCOCiCCC<lGClOi— I GO -*l i— I t- -eH CC CO CC C<> GC in i— I GC -i"1 r— I Ci -*
^c»soaocot-§5i>i-i«i>Hio©ioo»<i*c»«oaDc^i>w<O'-<«c©»fi
iaosccco<Nt-i-i?ooinci-+icocot-T-iecoinci-*cocoJ^<M«ei— i m <M <M co cc -* •«*( in m ec «c cc t- t— co GO cs ci o o o T-H i— i o\ <M cc co -* -*
(O «O <O tO «O *O <O <C tC ^r O CC tC O O «O tO b» t» !>• b» t» ««• b» t» l«» l> t*
>n in » m in in in i in in in in in in in in in in in in in in in in in in in in
ini— i oo -^ i— i ci t>c^«Cr-H?co OOeOt*e^«Oi-l
i:^ t^ cc cc C5 o o o I-H ^-i t-i <M <M co cc ^H -* m m m en ?c t^ t^ QO cc c;
in in in in in in m m m m m m m m m in m in m m in in in in m >n m in
C^<MC<IC^<M(MC^<M(MC^M<MCOCOCOCOCCCCCOCOCO?OCOCCCOCOCOCO
in in in in in in in in in in in in in in m m m in in in in in in in in m in ip
t-<Mt~-rHtDi— (inOinC5-*C3COOOC<lt^O)iC'r-l?nOin
c^t^i— itcomO5-+iGOcoi^-i— iscoinoHHcccot^c^tCr— iin <<K'*»a»o<o«o«ot^t^
i in in i in i i in in in in in in in in in in in in in in in in in in in in
cc tc c<i oo «n i— i oo •**< i— • i Oi -^
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O O O O O O O O O O O O O O O O O O O O O O i— I r-H r— i rH I-H
m in in m m in in m m in in in in m in in m in in in in in in in in in in
«o<NQOiai-Hco-^r-(t — JH «cco eofMcoini-noo^i-ic:-*! co eo t- c5 »> »-i w t-i in o m cs -H as cc cc <M t^ <M ?c I-H «o o MS
c<ii>-i— itcoinO5-*cccot>-r-^^coinci-+ioccoi>-c<iec!— i m co cc cs cs o o i— i i— i i— i <M cq co co -t- -^ »n m >n cc is t^ t^- oo oo c> os
CC OO GO OO CC GC G7i Ci CTi Ci C5 Ci Ci Ci Ci Ci Ci Ci
m m m cc tc t- t— oo oc ci cs Ci o o •— i i— i »M c^i co co co •** •* m m «c «c i~-
t— t— t-t— t-t-t-t— t-t--t-l^-GOGOGOGOGOGOGOGOGOGOGOOOQOOOQOOO
CN t- I-H to i— iinoinci-Cicooo(Mi~-(Mccr— i n ci co 'CC <N t- i— i ec o m Ci -^ oo co t— i— i to o m ci -* cc co t- w cc i— i m
>n m >n m in m m m m m co cc cc «c «o
^-H_H-t(-^^t(^-tl-hl-tl-H^-tl-*-«tl-tl
DECIMALS OF 1 TON.
53
I1— t— CO CO Si Ci O O r-H i— I i— i i?l <M CO CO -H -H 1C 1C 1C CO CO 1-- t- CO CO C5 C5
COCOOiCOfNGOiCi— ICO-tli— ll>--+l «OCO CO<MCOiC<— IGC"*i— IC5-*
-fCicococot'-'Mt—'— itoi—iico»aci-*i35soooc<it— M«OI— i co o ic
~* CO CO t- iM CO i— liCO-*C5COGO(MCO'-iiCO~fC5COCO<Ml-i— I CO O 1C 1C 1C CO CO 1^ t- CO GO C5 OS O O O r-i ,— i C-J <M CO CO CO -* -* 1C IS CO CO l-
S3
-t-b5IOGOCOl^-'>ll~^^COi-HiCOlCC5-tHC?;Coi;CN|t^OqcC'-HCCOiC iCCiCOCOC<ll>-i-HCOOiCCJ'^ICOCOt— i— (CCOlCCS-^COCOt—CNICOi— i 1C
£'MX)»ft'— (QO^i— II— -+l CCCO 1C (M 00 lf5 r-H GO -fi i— t Ci -^1 OCOI"-'MI— i— (COi— liftO>CCS-^OSeOQOC^t-MCOi— I ?O O ) ^C^tCJi— liSO-+lCiCOOOM«CrHOO'*lClCOOO(Mt-rHCC
«CrHOO'*lClCOOO(Mt-rHCCO O O i— li—H'M!MfCJO-ti-tl-t<<Ol^CCCC^t'-COGOOOO5C5OOi— li— (<M
a ia >c »a >a <a >?: ic >o ia o is >c ic >c ic »c 10 ic ic <ic to co tc o
-f< C5 SO OC JO t^ <M I- rH
iCCSSOOOWI^-f— tSCO»C I— t^- 30 OO O» O» O O <-H i— i
t- C^ CO ^-t CO O 1C
i— I 1C OOOOOiCi
iCrHOO^i-lt -- H COCO i O5 CO 00 CO t- Cq t^ i-H CO ^H 1C O 1C Si -H 55 CO 00 *M 1^ «M CO »-l
ao 55 i> N «o 1-1 us p •g* o» w op w «c — i «Q O
»
« OD <M t- i-i so O
'C CO CO I—
2
>C 1C 1C -«O CO t— t— X' GO C5 C5 C5 O O i— I •— I M C<l CO CO CO -r -fi 1C 'C CO CO I— <M 'M' <M fr\ iM (M <M 'M <M (M <M <M CO CO CC CO CO CO CO CO CO CO CO CO CO CO CO CO
cp^cpcpcptpcpcpcccccpcptocccccccccccocpcpcccpcpcpcpcpcp
COCOC5CO<M<X>lC-HGO-t<'— lt--H COCO COdCOlC^HOO-tli— IO5-+I
-HCiCOCOCOt-'>JI^^-ICCi-HiCOlCC5-HC5COCC'MI^'M'^i-(CCOlC
1C Ci CO CO <M t^ r-( CO O 1C C5 -H CO CO I— —< CO O 1C Ci -+< CC CO I- «M CC rH 1C
n c-i co co -+1 -+i »c ic to co cc t- i^ cc x Ci c; c: o o ^- -H £i 7-1 co co
COCOCSCCiMCOltirHQO-^r— it—'+l COCO COlMCOlCi-HOO^Ir— lCi-tl •^CSCOCCCOt— <Mt— t— (?Ci— I »{J O >ft wJ -t< C7i CO CO d t— (>1CO>— (COOiC -HCCCOI^-'7<lCC-HlCO-tlC5COOOMCCi— 'iCO-fCSCO
54
GAS ENGINEER'S POCKET-BOOK.
COCCCiCO'7<ICOlCr~IOO-+li— It^-H^ COCO
n L^t^cocociCiOOi— irHi— «oflc^eoei5^H-5iciBiccocot>-i>-cococici
COCOCOCOCOCC'CiCiCiC^OCiC^CiCiOCiCiCiCiCSCiCiCiCiOCiCi
COCOCiCO<MCOiCr-IGO-*i-lt~-*l COCO
>CiCiCCOCOl^l>-COCOCiC^CiOOrHrH<>l<NCOc6cC-+l~+llCiCCOCCl>' '-- l_— l>- t— l^- 1^- l^- t- I:— t~- t~ I— CO CO CO CC 'CO CO CO CC '00 CO CO X CO GO CO CO
1> "
CC CO Ci CC <M GO 1C r~ ICO-MrHr>--7HiCCOCO CO'MOOiCrHCO'tlrHCi'^l *•* Ci CO CO CO t- CM t^ i-H CO rH 1C O 1^ Ci -H Ci CO CO' CN I- rM CO rH CO O >C 1C Ci CO -CO CN t- rH CO O 1C Ci -H CO CO CO rH CO CT 1C CS -H CC CO I- CN CO rH 1C
to cb to to to co co to co to co co co co to to tc i~ i- ft h- r- r'-- t- ^ i-I i— i- OOOpCpobOOOOOOODOOQpOOClOOOQOOOOoOpaOflpaOOOapOOGOaDQOQOQO
CC CO Ci CC CN X >C rH X -tl i-H l>- •-£ COCO CC<MCOlOi— ICO^i-HCi-tl
O ^ x cV: i- £i to rH ic o ^ Ci cc x ^j cc I-H ~c o ^ Ci cc x^ i- rH cc o
I X CO CO CO CO CO X CO CO X X CO CO X X X CO CO CO CO CO CO CO CO CO CC CO CO
-tl Ci CO CO CO l^ M 1^ i-H CO rH 1C O O Ci ^-H Ci CO CC 7-1 1^ ^) CO rH CO O 1C 1C Ci CO CC Ol l^- rH CO C: 1C Ci -HH CO CO t^- rH CO O 1C Ci -H X CO 1- C^J CO r-H 1C
1^. 1^. CO CO Ci Ci O O' i— i i— I rH C<J CN CO CO
CO CO CO CO CO CC*
-f Ci CO CO CO l-^ GST l^ rH CO rH 1C O 1C Ci ^ Ci CO CO CM I- !M CO rH CO O 1C
-H CC CO l^- CM CC rH 1C O -f Ci CO CO C<J CO rH 1C O -+" Ci CO • CC <M t-- rH CO O
1C 1C 1C tO tO t- I- CC X Ci Ci Ci O O rH rH CN 'M CO CO CO -f 'fl 1C 1C CO CO l^
(M 0-J <>1 'M 'M (M CN (M (M CN| <M (M CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO CO
CO> CO CC CO CO CO CO CO CO CO CO CO CO CO CO CO CC CO CO CO CO CO CO CO CC ^CO CO CO
COCOCiCC<M'CO>CrHCO'tlrHt H COCO CO-MXlCrHCC'^HrHCi-^
-f Ci CO CO CO t>- <M t~- rH CO i— I 1C O 1C Ci -f Ci CO CC »M I- I'M CO i— I CC O >C
|lCCiCOCOCNt^rHCOOlCCi-rHCOCOt^rHtOOlCCi-HCOCOt^(MCOr->C COCOt-l>OOCOCiCiOOOrHr-iC>?<NCOCO"H-->-
cocpcpcpcococpcocpcooooococp
CO CO Ci CO CN X 1C rH X -H^ rH t^» T^ CO CO CO C^l CO >C rH CO "^ rH Ci ~f -H C5 CO X CO !•>• Tl l~~ rH CC rH 1C O JC Ci -* Ci CO X <M I.-- C-1 CO •— I CO O 1C Q i -H X CO t— <N CO rH 1C O -f Ci CO CO <M CO rH i.C O -H Ci CO X »M t^ rH CO O
COCOCiCO(MCOlCrHOO-tlrHl>--tl COCO CCi>lCO>CrHCO-^^HCi-+l -H Ci CO CO CO l^ <M t^ rH CO rH 1C O 1C Ci -C Ci CO CO <M t- <M CO rH CO O 1C — 1C Ci CO X 0-1 I- rH CO O 1C Ci -* .CO CO 1^ rH CC O 1C Ci -H X CO t^ 01 CO rH 1C TO 1^ I- X X Ci Ci O O rH rH i-< ~1 »>7 CO CO -H ~H 1C iC 1C CO CO 1^- t>- X X Ci Ci
XCOXCOXXCiCiC-.CiCiCiCiCiCiCiCiCiCiCiCiC3CiCiCiCiC-.Ci
CO CO Ci CO <M X 1C rH X -H rH I H CO CO CO -M CO 1C rH X ^ rH Ci ^
-f Ci CO -V CO I- -M t^ r-H CO -H 1C ~ 1C Ci -H Ci CO X ?\ I- <M CO rH CO O 1C
-^XCOI-'MCOrHlCO-HCiCOXiMCOr-iCO-H-CiCOX'Mt-rHCCO
ic ic ic to to i- j- x x c-. C-. C-. — c r^ — ri ri co co co ^H -*• ic i_c cc co r-
CO CO Ci CO <M X 1C rH CO -f — ' I' H CO CO CO *N X 1C rH CO -+< i-H Ci -H
-t^ Ci CO X CO 1^ iM 1^ rH CO rH 1C O 1C Ci -h Ci CO X <M I- »M CO rH CO O 1C
1C Ci CO X <M I- rH CO O 1C Ci -f X CO I- rH CO O 1C Ci -* X CO 1^ 'M CO rH 1C
(M <M CO CO -* -H 1C 1C CO CO CO I- I- X X Ci Ci O O O rH -H <M 'M CO CO MH -H
co co to to co co to to co co co co co to co co co i- i^ r^ i- t^ i^ i- t- t- j^ i-
COCOCitO<MGC»OrHCC-Hr-Ht H COCO CO'MCClCrHX'frHCi-H
-5 C> CT CO CO «- <M ^ rH CO rH 1C O 1C Ci -H Ci CO X ^ t^ (M CO rH CC O 1C
^ X CO I- Vl CO rH 1C O -H Ci CO X <M CO rH 1C O -H Ci CO X <M t- rH CC O
O C5 r^ rH rf-T W CO CO -* -^ -+- 1C 1C CO CO 1^ 1^ CO X X Ci Ci O O rH rH <M
1C >C iC 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C 1C CC CO CO tO CO
t^ !•— l^ t- 1^-
DECIMALS OF 1 TON.
55
COCOO:CO<NCCltrHGO-HrHt H COCO CO<NGOltrHCO-*lrHCS-7H
-JH OS CO 00 CO t- CN !>• rHI CO rHj ifi O it CS -H CS CO GO C<l t>- C^l CO rH CO O »O ItOSCOGOfMt-r-ICOOltOS-tlGOCOt^r-ICOOltOS-rHGOCOt-INCOrHit t- t- 00 CO OS OS O O rH rH ^H CN IN CO CO -H -* It It It CO CO I- t- CO GO OS OS
OOCOGOGOCOGOCSOSCSCSCSCSCiOSCSOCSCSCSCSCSCJCSOSOiCSCSCS OSCSCSCSOSOSCSCSCSCSCSOSCSCSCSOSCSCSOSCSOSCSCSCSOSOSOSOS
CCCOOSCOiNCCltr-IGO-HrHl>-* COCO CCfNGCltrHCC-HrHCS-* -+<C5COCOCOt-<Ml>-rHCCi— lltOltCS-HHOSCOGOfNt-lNCCrHCOOlQ <« -HH GO CO t> IN CO r- (itO-^CSCOGOlNCCrHitO-^ICSeOGOlNt-rHCCO
It It It CO CO l>- l>- GO GO OS OS OS O O i-H rH CN CS CO CO CO -^ ~t* It It CO CO t>»
CnOSCS^CSCSCSCSOSCSCSOSCSOSCSCSCSCSOSCSOSCSCSCrsCSCsaS
cecOC5CC<NCOitrHOo'H;rHb..--h ^ CO CO CC<NGOitrHCO~*l'-^CS~* CSMCOCSt^i^CCC>t5^GO^t^^CCOitC5-t<COCOl>'CvlcerH»O
Xcscs^cscscsXcscscscso-SSS^oscscscscjcscjcsoscsas
COCSCCCxlGOltrHGO-+<rHr>--+( COCO CCOlGCltrHGO-flrHCS-*!
CS CO GO CO t^ W l>- r-H CO •— < it' O It OS -H-l CS CO GO CM t^ CN CC i— I CC O >t
O rH rH fl <?I TC CO ^ ~H ^h It It CC CO t^ t^ GO GO' GO OS OS O O rH rH (N
- It It It It It It
-* OS CO GO CO t^ M t^ rH CO rH it O It O5 ^ O5 Ct CO ^1 t- tl CO rH CO O it It OS CO GO CXI I— i— I CO O It OS -HH CC CO t~- rH CO O it OS -+i GO CO t- <>] CC rH 1C!
t^- t^ GO GO OS OS O O rH rH rH C^l I>1 SO 'CO -Hr| -f It 1C it CO CO t>- t— GO GO1 OS OS
I
^ OS CO GO CO I- M l^ rH CO rH It O It OS ^ OS CO GO' C^l 1^ CN CO rH CO O it -tl OO CO t— IN CO rH It O -H O CO GO <N CC rH It O -H OS CO CO Cxl 1^- r- 1 CO O
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6 i o- JB
GAS ENGINEER'S POCKET-BOOK.
Equivalent Weights.
Metric. English.
1 milligramme = -0154 grain. 1 centigramme 1 decigramme 1 gramme 1 decagramme 1 hectogramme
1 kilogramme
1 millier or tonne = 19-6841 cwts.
.== '1543
= 1-5432
= 15-4323
= -3527 oz."
= 3-5274 .,
= 2-204621 25 Ibs.
|
English. |
Metric. |
|
L grain = |
•0648 gramme. |
|
L drachm = |
1-7718 „ |
|
07. = |
28-3495 |
|
Ib. = |
•4535926 kilogramme. |
|
stone = |
6-3503 „ |
|
quarter = |
12-7006 „ |
|
cwt. •= |
50-8024 „ |
|
1 fnn — 1 |
1016-048 ., |
|
L I1 Ml — ^ |
1-01605 metric tonne. |
Equivalent Liquid Measures.
Metric. 1 centilitre 10 cubic centimetres 1 decilitre 1 litre 1 decalitre 1 hectolitre 1 cubic metre
English. •0176 pint,
= -1761 ., = -2201 gallon. = 2-2009 „ = 22-009 „ = 220-09
English. Metric.
1 gill or quartern = -1420 litre. 1 pint = *5679 „
1 quart = 1-1359 „
1 gallon = 4-5435 „
|
Equivalent Measures of Length. |
|
|
Metric. |
English. |
|
1 millimetre = |
•03937 inches. |
|
1 centimetre = |
•3937 „ |
|
1 decimetre = |
3-93704 „ |
|
f 39-3704 |
|
|
1 metre = |
( 3-2809 feet. |
|
1 decametre = |
32-8087 „ |
|
1 hectometre = |
109-3623 yards. |
|
( 3280-369 feet. |
|
|
1 kilometre = |
< 1093-623 yards. |
|
1 -62138 mile. |
|
EQUIVALENT MEASURES OF LENGTH. |
|||
|
English. |
Metric. |
||
|
inch |
— - |
25'4 millimetres. |
|
|
link |
— • |
•2012 metre. |
|
|
foot |
— |
•3048 |
|
|
yard |
— - |
•91439 |
|
|
fathom |
— |
1-82878 |
|
|
rod, pole or |
perch = |
5-02915 |
|
|
chain |
— |
20-11662 |
|
|
1 furlong |
= 1 |
201-1 6(>2 0-20117 ki |
lometre. |
|
1 mile |
I " '1 |
1609-3296 metres. 1-6093296 kilometres. |
57
1 admiralty knot | _ or nautical mile f
1-85315
|
Pounds Square inches Circular inches |
X X X X |
•0089; •0004? •007 •0054( |
|
|
Cylindrical inches |
X |
•0004f |
|
|
Cubic |
inches |
X |
•0005* |
|
M |
M |
X |
•0036C |
|
?» |
feet |
X |
6-232 |
|
Cylindrical inches |
X |
•0028? |
|
|
Jj |
feet |
X |
4-895 |
|
Cubic |
inches |
X |
•281 |
|
5> |
55 |
X |
•283 |
|
X |
•3225 |
||
|
M |
55 |
X |
•3037 |
|
5> |
55 |
X |
•26 |
|
J) |
55 |
X |
•4103 |
|
5» |
5) |
X |
•2636 |
|
«> |
• ? |
X |
•4908 |
|
Cylindrical inches |
X |
•2168 |
|
|
?J |
X |
•2223 |
|
|
X |
•2533 |
||
|
X |
•2385 |
||
|
X |
•2042 |
||
|
X |
•3223 |
||
|
X |
•207 |
||
|
X |
•3854 |
= square feet.
•0004546 = cubic feet. •00058 = „ „ •003607 = imperial gallons.
= Ibs. avoirdupois of wrought iron. = ., „ ., steel.
= „ ., „ copper.
=^ .. ., .. brass.
= 55 55 51 zinc.
= ., ., h lead.
= 55 55 55 tin.
= -5 .5 „ mercury.
= ., „ ., wrought iron.
— •; ., .. steel.
= 55 55 55 copper.
= „ ., ., brass.
= ., „ ., zinc.
= ., ., ., lead.
= 55 55 55 tin.
= -5 5, ., mercury.
Metric Equivalents. To convert grains into grammes
grammes into grains
drachms into grammes
ounces (avoirdupois) into grammes
pounds „ „ „
cubic centimetres into grains „ „ „ drachms
„ „ „ ounces (avoirdupois)
pints into cubic centimetres
litres into ounces (avoirdupois)
gallons into litres
0-065 15-5 3-9 28-4 453-6 15-5 0-29 0-036 X 473 X 35-3 X 3-8
58:.
GAS ENGINEER'S rocKET-BOOK.
To Convert Grammes, Decigrammes, Centigrammes and Milligrammes to Grains.
1 gramme = 15-4:323 grains. 6 grammes = 92*5938 grains.
2 „ = 30-8646 ., ' 7 ., = 108-0261 .,
3 ;, = 46-2969 ;, 8 ;, = 123-4581 „
4 „ = 61-7292 ., 9 „ = 138'8907 „
5 ., = 77-1615 „
For the number of grains in a decigramme shift the decimal point one place to the left, thus, 1 decigramme = 1-51323 grains.
For the number of grains in a centigramme shift the decimal point two places to the left, thus, 1 centigramme = -154323 grains.
For the number of grains in a milligramme shift the decimal point three places to the left, thus, 1 milligramme = -0154323 grains.
Cubic Feet into Cubic Metres.
|
Cubic feet. |
Cubic metres. |
Cubic feet. |
Cubic i letres. |
Cubic feet. |
Cubic metres.' |
Cubic feet. |
Cubic metres. |
|
1 |
•0283 |
31 |
•8778 |
61 |
1-7272 |
91 |
2-5767 |
|
2 |
•056:; |
32 |
•9061 |
62 |
1 '7555 ' |
92 |
.2-6050 |
|
3 |
•084S) |
33 |
•9344 |
63 |
1-7838 |
93 |
2-6333 |
|
4 |
•1133 |
34 |
•9(527 |
64 |
1-8122 |
94 |
2-6616 |
|
5 |
•1416 |
35 |
•9910 |
65 |
1-8405 |
95 |
2-6899 |
|
6 |
•1699 |
36 |
1-0193 |
66 |
1-8688 |
96 |
2-7182 |
|
7 |
•1982 |
37 |
1-0477 |
67 |
1-8971 |
97 |
2-7466 |
|
8 |
•2265 |
38 |
1-0760 |
68 |
1-9254 |
98 |
2-7749 |
|
9 |
•2548 |
39 |
1-1043 |
69 |
1-9537 |
99 |
2-8032 |
|
10 |
•2831 |
40 |
1-1326 |
70 |
1-9820 |
100 |
2-8315 |
|
11 |
•3115 |
41 |
1-1609 |
71 |
2-0104 |
200 |
5-663 |
|
12 |
•3398 |
42 |
1-1892 |
72 |
2-0387 |
300 |
8-494 |
|
13 |
•3681 |
43 |
1-2175 |
73 |
2-0670 |
400 |
11-326 |
|
14 |
•3964 |
44 |
•2459 |
74 |
2-0953 |
500 |
14-157 |
|
15 |
•4247 |
45 |
•2742 |
75 |
2-1236 |
600 |
16-989 |
|
16 |
•4530 |
46 |
•3025 |
76 |
2-1519 |
700 |
1 9-820 |
|
17 |
•4814 |
47 |
•3308 |
77 |
2-1803 |
800 |
22-652 |
|
18 |
•5097 |
48 |
•3591 |
78 |
2-2086 |
900 |
25-483 |
|
19 |
•5380 |
49 |
•3874 |
79 |
2-2369 |
1000 |
28-315 |
|
20 |
•5663 |
50 |
•4157 |
80 |
2-2652 |
1.500 |
42-472 |
|
21 |
•5946 |
51 |
•4450 |
81 |
2-2935 |
2.000 |
56-620 |
|
22 |
•15229 |
52 |
•4724 |
82 |
2-3218 |
2500 |
70-787 |
|
23 |
•6512' |
53 |
•5007 |
83 |
2-3501 |
3000 |
84-944 |
|
24 |
•6795 |
54 |
1-5290 |
84 |
2-3785 |
4000 |
113-240 |
|
25 |
•7079 |
55 |
1-5573 |
85 |
2-4068 |
5000 |
141-574 |
|
26 |
•7362 |
56 |
1-585(5 |
86 |
2-4351 |
6000 |
169-888 |
|
27 |
•7645 |
57 |
1-6140 |
87 |
2-4634 |
7.000 |
198-184 |
|
28 |
•7928 |
58 |
1-6423 |
88 |
2-4917 |
8000 |
226-480 |
|
29 |
•8211 |
59 |
1-6706 |
89 |
2-5200 |
9000 |
254-814 |
|
30 |
•8494 |
60 |
1-6989 |
90 |
2-54X3 |
10.000 |
283-148 |
|
• |
CUBIC METRES INTO CUBIC FEET. Cubic Metres into Cubic Feet.
59
|
Cubic Cubic |
Cubic |
Cubic |
Cubic |
Cubic |
Cubic |
Cubic |
|
|
metres feet. |
metres |
feet. |
metres |
feet. |
metres |
feet. |
|
|
1 |
35-3156 |
31 |
1094-7836 |
61 |
2154-2516 |
91 |
3213-7196 |
|
2 |
70-6312 |
32 |
1130-0992 |
62 |
2189-5672 |
92 |
3249-0352 |
|
3 |
105-9468 |
33 |
1165-4148 |
63 |
2224-8828 |
93 |
3284-3508 |
|
4 |
141-2624 |
34 |
1200-7304 |
64 |
2260-1984 |
94 |
3319-6664 |
|
5 |
176-5780 |
35 |
1236-0460 |
65 |
2295-5140 |
95 |
3354-9820 |
|
6 |
211-8936 |
36 |
1271-3616 |
66 |
2330-8296 |
96 |
3390-2976 |
|
7 |
247-2092 |
37 |
1300-6772 |
67 |
2366-1452 |
97 |
3425-6132 |
|
8 |
282-5248 |
38 ! 1341-9928 |
68 |
2401-4608 |
98 |
3460-9288 |
|
|
9 |
317-8404 |
39 11377-3084 |
69 |
2436-7764 |
99 |
3496-2444 |
|
|
10 |
353-1560 |
40 |
1412-6240 |
70 |
2472-0920 |
100 |
3531-560 |
|
11 |
388-4716 |
41 |
1447-9396 |
71 |
2507-4076 |
110 |
3884-716 |
|
12 |
423-7872 |
42 |
1483-2552 |
72 12542-7232 |
120 |
4237-872 |
|
|
13 |
459-1028 |
43 |
1518-5708 |
73 |
2578-0388 |
130 |
4591-028 |
|
14 |
494-4184 |
44 |
1553-8864 |
74 |
2613-3544 |
140 |
4944-184 ' |
|
15 |
529-7340 |
45 |
1589-2020 |
75 |
2648-6700 |
150 |
5297-340 |
|
16 |
565-0496 |
43 |
1624-5176 |
76 |
2683-9856 |
160 |
5650-496 |
|
17 |
600-3652 |
47 1659-8332 |
77 |
2719-3012 |
170 |
6003-652 |
|
|
18 |
635-6808 |
48 |
1695-1488 |
78- |
2754-6168 |
180 |
6356-808 |
|
19 |
670-9964 |
49 |
1 730-4644 |
79 2789-9324 |
190 |
6709-964 |
|
|
20 |
706-3120 |
50 |
1765-7800 |
80 |
2825-2480 |
200 |
7063-120 |
|
21 |
741-6276 |
51 |
1801-0956 |
81 |
2860-5636 |
250 |
8828-900 |
|
22 |
776-9432 |
52 |
1836-4112 |
82 |
2895-8792 |
300 ! 10594-468 |
|
|
23 |
812-2588 |
53 |
1871-7268 |
83 |
2931-1948 |
350 '12363-46 |
|
|
24 |
847-5744 |
54 |
1907-0424 |
84 2966-5104 |
400 |
14126-24 |
|
|
25 |
882-8900 |
55 |
1942-3580 |
85 |
3001-8260 |
500 |
17657-80 |
|
26 |
918-2056 |
56 |
1977-6736 |
86 |
3037-1416 |
600 |
21189-36 |
|
27 |
953-5212 |
57 |
2012-9892 |
87 |
3072-4572 |
700 |
24720-92 |
|
28 |
988-8368 |
58 |
2048-3048 |
88 3107-7728 |
800 |
28252-48 |
|
|
29 |
1024-1524 |
59 i 2083 -6204 |
89 J3143-0884- |
900 |
3t734-04 |
||
|
30 1059-4680 |
60 2118-9360 |
90 3178-4040 |
1000 |
38847-16 |
Demy . Medium Royal . Imperial Elephant
Sizes of Drawing Paper,
20 X 15 Columbier . . . 34 X 23
22 X 17 Atlas . . . . 33 X 26
24 X 19 Double Elephant . . 40 X 26
31 X 21 Antiquarian. . . 52 X 29
27 X 23 i Emperor . . . 68 X 48
60
GAS ENGINEER'S POCKET-BOOK.
Colours used in Architectural and Engineering Drawings.
For Brickwork in plan or section (to be executed) . . „ Brickwork in elevation.
Flintwork or parts of brick- work to be removed
Granite .
Cement or Stone .
Concrete .
Clay Earth .
Plaster .
Slate
Tiles
Wood
English Timber, not Oak ,
Oak or Teak
Fir Timber .
Mahogany .
Iron, wrought ,, cast .
Lead
Copper. ...
Brass ....
Gunmetal .
Glass .
Leather .
Meadow land
Sky effects .
Crimson Lake or Carmine. Venetian red or Crimson Lake and Burnt Sienna (light).
Prussian Blue. Violet Carmine. Sepia.
„ mottled with Burnt Umber. Burnt Umber. Sepia (light).
Indigo with Crimson Lake. Indian red. Burnt Sienna. Kaw „ Burnt ., Indian yellow.
„ red. Prussian blue. Payne's Grey. Indigo or light Indian-ink. Crimson Lake with Gamboge. Gamboge. Dark Cadmiums. Cobalt mottled. Vandyke brown. Hooker's Green. ; Cobalt Blue.
Weight of Materials.
|
MATES uxs. |
Weight of One Cubic Foot. |
Cubic Feet per Ton. |
|
Ibs. |
||
|
37 |
601 |
|
|
„ 52 feet = 1 chaldron . . . |
||
|
100 |
22f |
|
|
„ in cement . ... |
110 |
20f |
|
Bricks, red kiln |
135 |
17 |
|
., common |
110 |
20f| |
|
„ London Stock .... |
115 |
19f |
|
„ Welch fire |
150 |
15 |
|
Cement, Portland .... |
84 |
26f |
|
„ „ cask 4 bushels = . |
5 feet |
2 cwt. |
|
., Roman |
60 |
37£ |
|
'„ „ cask 5 bushels = . . |
6 feet |
4 cwt. |
|
Chalk |
140 to 160 |
15£ to 13| |
|
Clav |
120 to 135 |
18f to 17 |
|
y |
WEIGHT OF MATERIALS.
61
|
MATKBIALS. |
Weight of One Cubic Foot. |
Cubic Feet per Ton. |
|
Coal, Cannel and Welsh „ Newcastle Coke Concrete Earth |
Ibs. 84 80 47 120 95 to 126 164 157 187 184 112 to 120 450 487 53 44 88 119 90 118 lib 54f BSf 57| 62£ 64 |
26| 28 48 18} 23i to 18 ISf 14* 12 12J 21f to 18f 5 4* 42i 51 25i 19 23i to 25 19 131 13* 14i 141 15 14f 16 12i to 13 20 41 38 39 35 35 |
|
Flint Glass, Crown . . . . . „ Flint |
||
|
„ Plate. . . . . . Gravel |
||
|
Iron, cast „ wrought Lime, stone „ chalk Mortar, from (old) .... ,. to (new) Sand, pit ,, river Shingle Slate . . . . . . ' . |
||
|
Stone, Granite ,, Purbeck . . • . . „ Yorkshire „ Craigleith „ Derby „ Portland „ Bath |
||
|
Marble |
||
|
Tiles, average Oil of Turpentine „ Linseed Whale |
||
|
Rain Water (252 gallons per ton) Sea „ (224 „ „ ) . . |
||
|
Gallon of water =10 Ibs. = 277£ cubic inches. 6£ „ „ = 1 cubic foot nearly. Roofing — 1 square of 100 feet slating = 10i cwt. „ 1 „ and timbers = 15£ 1 tiling =15i , „ 1 „ and timbers = 21 , „ 1 with 7 Ib. lead = 10 „ 1 „ and timbers = 17 , 1 with 6 Ib. lead = 8i , „ 1 „ and timbers = 15£ , „ 1 with 16 gauge zinc = 3£ , „ 1 . „ and timbers = 10i , |
62 GAS ENGINEER'S POCKET-BOOK.
Miscellaneous Articles.
One barrel of tar = 26| gallons.
Battens = boards 7 inches wide.
Bushel of coal = 80 Ibs.
„ coke = 45 „
„ quicklime = 70 „
Chaldron of coal = 25| cwts.
„ coke = 12 J to 15 cwts.
Fodder of lead = 19£ cwts.
Hundred of deals = 120 in number.
.. nails =120 „
Load of bricks = 500 „
„ lime (1 ton) = 32 bushels.
„ sand = 36 „
Planks = boards 12 inches wide.
Sack of. coal = 224 Ibs.
Square of planking =100 superficial feet.
; „ slate = 100
Weight of Earths, Rocks, etc.
Cwt. I Cwt.
1 cub. yd. sand . . = 30 1 „ gravel . = 30
1 „ mud . . = 25 1 „ marl . . =• 26 1 „ clay . . = 31
1 chalk . . = 35 to 36
1 cub. yd. sandstone . = 39 1 ,. shale . . = 40 1 .. quartz . = 41 1 . ., granite . . = 42 1 ' .. trap . . = 42 1 slate . = 43
L ., cannel coal = 81 to 87 | Natural Slopes of Earths with the Horizontal or Angles of Repose.
|
Gravel, average |
. 40° |
||
|
„ and sand mixed |
.- 38° |
||
|
Dry sand |
. 37° |
to 38° = |
1-33 to 1 |
|
Sand .... |
. 21° |
to 22° = |
•263 to 1 |
|
„ fine dry |
. 32° |
||
|
Vegetable earth or peat |
. 28° |
= |
1-89 to 1 |
|
„ new , |
. 34° |
||
|
Compact „ |
. 48° |
to 50° = |
•09 to 1 |
|
Loamy ,, |
. 40° |
= |
1-2 to 1 |
|
Shingle, average |
. 39° |
to 40° = |
1-2 to 1 |
|
„ -clean. |
. 36° |
||
|
Bubble, average . |
. 45° |
sa |
1 to 1 |
|
Clay, well dried |
. 45° |
= |
1 to 1 |
|
„ stiff or dry mud |
. 45° |
= |
1 to 1 |
|
„ wet, average |
. 16° |
||
|
., „ London |
. 15° |
||
|
Coal .... |
. 33° |
= |
1-65 to 1 |
1 cub. yd. rock in large pieces = when excavated T50 c. yds.
1 „ ,. medium as due: = „ „ 1 '25 to 1-30 c. yds.
1 „ chalk . . . .= „ „ l'30c. yds.
1 „ sand and gravel . = ., „ 1-07 „
1 „ clay and earth . . = ,. „ 1-2 to 1-25 c. yds.
RESULTS OF POWER. Observed Results of Power (Nystrom).
63
|
Work! |
Effects |
||||
|
Description of Works. |
hours pei- |
Force. |
Velocity |
of ft. Ibs. per |
Horses. |
|
day. |
second. |
||||
|
A man can raise a weight by a |
|||||
|
single fixed pulley . . |
6 |
50 |
0-8 |
40 |
0-072 |
|
., working a crank |
8 |
20 |
2-5 |
50 |
0-090 |
|
., on a treadwheel(horizontal) |
8 |
144 |
0-5 |
72 |
0-130 |
|
„ in a treadwheel (axis 24° |
|||||
|
from vertical) . . . |
8 |
30 |
2-3 |
G9 |
0-125 |
|
„ draws or pushes in a hori- |
|||||
|
zontal direction |
8 |
30 |
2-0 |
GO |
0-109 |
|
„ pulls up or down . . . |
8 |
12 |
3-7 |
44-4 |
0-080 |
|
„ can bear on his back . |
7- |
~$5~ |
2-5 |
237-5 |
|
|
A horse in a horsemill, walking |
|||||
|
moderately |
8 |
106 |
3-0 |
318 |
0-577 |
|
„ „ „ running fast |
5 |
72 |
9 |
648 |
1-178 |
|
An ox in a horsemill walking |
|||||
|
moderately |
8 |
154 |
2 |
308 |
0-518 |
|
A mule „ „ |
8 |
71 |
3 |
293 |
0-308 |
|
An ass „ „ „ |
8 |
33 |
2-05 |
87-4 |
0-160 |
|
Ori bad foot roads like those in |
|||||
|
Peru a man can bear . . . |
10 |
50 |
3-5 |
175 |
|
|
Llama of Peru can bear |
10 |
100 |
3-5 |
350 |
|
|
Donkey can bear . . ' . . |
10 |
200 |
3-5 |
700 |
|
|
Mule can bear . . |
10 |
400 |
5-0 |
2000 |
Man Power.
Efforts -exerted for short periods of time. R.A. rule.
Pushing a load horizontally . . . . 100 Ibs.
Pulling ., „ ....'. 70 „
Tractive -force in dragging a cart . . . 40 „
Lifting a weight from the ground by the hands . 150 „
Carrying on his shoulders 120 „
On a winch for continuous work , . . 15 to 20 Ibs.
When a number of men are pulling on a rope, the effort per man will average very much below the above quotation, and the greater the number the less the average per man. 24 men will not pull half as much again as 12 men. The most advantageous application of a .man's power in hauling is in a slanting direction downwards, as his weight is added to his strength.
Power of Horses.
Rate (miles per hour) =2 3 3J 4 4£ 5 Tractive force in Ibs,, ==166 125 J04 83 62 41
64
GAS ENGINEER'S POCKET-BOOK.
To set out a perpendicular measure a base of 4 parts, perpendicular measuring 3 parts and diagonal 5 parts.
To Divide a given Line into any number of Equal Farts.
Let A B be the line to be divided, then at B erect perpendicular B C, then on the line A C set out the divisions by any convenient scale, and from the points as D E F draw lines perpendicular to A B, which will cut at G H K the divisions required.
This method is useful for making scales to uneven dimensions.
Excavating.— A man can dig from 5 cubic yards in hard gravel to 10 cubic yards in loose ground per day.
1 tori of light soil = 18 cubic feet.
Carts usually hold 2£ tons or 45 cubic feet.
Piles driven until they are in firm ground will stand 1000 Ibs. per sq. inch of area of head, but when depending only upon the friction of their sides 200 Ibs. per square inch.
On sloping ground step and stair the foundations.
A cubic yard of earth, before digging, will occupy about 1£ cubic yard when dug.
A dobbin cart will contain f cube yard.
Earth waggon, small size. 1£ „ „ „ „ large . 3 „ „
Wheelbarrow . . . ^ „ ,, A single load of earth = 27 cubic feet = 21 bushels. A double „ „ = 54 „ „ 1 cubic yard of gravel =18 bushels in the pit. 1 „ „ „ =24 „ when dug.
When formed into embankments gravel sinks nearly J in height and decreases 1 in bulk. If earth is well drained, it will stand in embankments about 1£ to 1.
Foundations. — 6 of good aggregate to 1 of ground lias lime will answer every purpose in ordinary cases, and should be about a foot wider than the' bottom course of footings, or 6 inches on each side.
SAFE PRESSURES ON FOUNDATIONS. 65
Whenever large weights occur, as on foundations of columns, angles of buildings, &c., Portland cement should be used in place of lias lime ; the dimensions can be increased if desirable.
Foundations in water are formed sometimes by rows of wooden piles so fastened together as to form a pier for the horizontal beams to be fixed upon, as in wooden bridges. A great objection to wooden piles is the fact that in water, fluctuating by the tide, the timber decays at the water-line and therefore requires to be sheathed with copper.
The following Pressures may be used with safety per superficial foot for Foundations : —
Tons. Rock . 13
Chalk . . . . . Solid blue clay and gravel London clay . . . 12 in. by 12 in. piles well driven
4
3 to 6 2
20 to 30
Well punned ground will sustain 1 ton per square foot, if punned each foot as filled in ; if not, not more than £ ton per square foot.
Gravel, good in foundation will uphold 5 tons per square foot.
Sandy gravel, near water, 1J tons per square foot.
Foundation always 2 ft. 6 in. below ground line.
Tons per sq. ft. Moist clay and sand (prevented from spreading laterally) . 1-36
Coarse sand and dry clay . 2*27
Firm bedded broken stones on dry clay 3-18
Loose impermeable beds with piling 1-82
„ „ „ „ „ and concrete. . . 2-73
It is necessary at all times to allow sufficient room for men to work in a trench where it has to be excavated more than 3 feet deep.
In loose ground a man can throw up about 10 cubic yards per day, but in hard or gravelly soils 5 yards will be a fair day's work. Three men will remove 30 yards of earth a distance of 20 yards in a day.
A yard of concrete requires about 3 hours' labour to mix and throw in, or, if in heavy masses and the materials handy, about 2 hours.
Burning clay into ballast is done by making a fire of small coal or coke breeze, and casing the same with clay, laying alternate layers of fuel and clay until the mass is burnt through. 2 tons of small coals will burn about 25 cube yards of earth. It is used for roads and concrete walls, and very frequently ground for mortar as a sub- stitute for sand, but it is essential that when used for such a purpose it be well burnt. Value, reckoning coals at 15*. per ton, 2s. 6d. per cubic yard.
19 cubic feet of sand, 18 ditto clay, 24 ditto earth, 15 J ditto chalk 20 ditto gravel, will each weigh 1 ton.
Footings. — Projection at bottom on each side should not be less, than half the thickness of wall at base, diminishing in regular offsets, and height not less than projection.
C.E. F
66 GAS ENGINEER'S POCKET-BOOK.
Punn all trenches before putting in concrete for foundations, and drain off all surface water permanently.
Sewerage about 5 feet head per mile is required to maintain a flow and to overcome f rictioa in small pipes.
Temperature increases about 1° F. for every 60 feet below the level of the ground.
Damp Course.— This is to prevent the moisture rising in the walls, and should be placed from 6 to 12 inches above the ground line. It can be made of slates laid in Portland cement, but recently asphalte has been adopted and is effective and economical. A glazed earthen- ware damp course, with ventilating spaces through its centre, has also been suggested.
Damp Courses for External Walls (Prof. H. Adams) : —
A course of slates throughout the thickness, 3 to 6 inches above
ground line.
A double course of slates in cement, 3 to 6 ins. above ground line, A layer of asphalte, i to ^ inch thick, „ „ „ „ „ A layer of cement, „ „ „ „ „ „ „ „ Taylor's patent glazed and perforated stoneware slabs, above
ground line. A layer of melted pitch with sufficient coal-tar mixed in to prevent
it setting too brittle. A layer of sheet lead 4 Ib. to 8 Ib. per square foot, with H in. laps
(the best). A layer of asphalted (i.£., tarred) roofing felt laid dry.
Inverted Arches should be turned from pier to pier in all heavy buildings to equalize the weight throughout the building and thus prevent unequal settlement. Arches are generally worked in half- brick rings, thus saving a vast amount of cutting and waste, but a course of headers should be thrown up every 3 or 4 feet, the upper course bonded over the lower, to tie the rings together. If this be properly attended to there will be no fear of the ri rigs separating when the centres are struck.
Hoop-iron bond, usually 1J in. X TV, in., should be well tarred and sanded before use and laid say every 5 feet in height of wall.
Asphalte damp course usually | inch thick at 12 inches above ground line.
Slate damp course, usually 2 courses thick, carefully bedded and laid in floating cement, upper layer overlapping the lower to prevent cracking ; they should project 1^ inches beyond the wall on each side.
A rise of & inch per foot span usually allowed in making centres for flat arches for settlements.
Wood slips, about f inch thick in joints of brickwork, better than wood bricks, as they are less liable to shrink.
Bricks of 6 parts breeze to 1 of cement will allow nails to be driven in and they do not shrink.
Brickwork. — The roughest and hardest of the stock bricks to be used should be selected for the footings, and worked English bond
BRICKWORK.
67
as high as where the facing commences ; or if the building is faced with stone or cement, English bond should be worked all through (excepting 9-inch walls), as it is much stronger than Flemish bond, although not so ornamental. 9-inch walls should in all cases be worked Flemish bond ; or, from the unequal length of the bricks, one side will be very rough. Where red bricks or seconds are used for facings, Flemish bond should be worked, and care taken to properly tie it in with the backing ; although a certain portion of the headers may be bats, every third should be whole bricks and occasionally cross or diagonal bond should be worked in the backing to prevent the wall splitting. In dry weather the bricks should be thoroughly soaked before laying ; each course of bricks must be properly flushed in with the trowel, and grouted every four courses to ensure stability in the work.
Bond.— Hoop iron, 1J inches wide, is now very generally used and with great advantage. There should be a course of hooping to each half brick in thickness, well tarred and sanded every 5 feet in height, and well lapped at all angles ; the course of bricks above and below the hooping should be laid in cement.
The quality of bricks and tiles may be told by the sound and by their appearance when broken. If they are well burnt through and when clapped together produce a good clear ringing sound, they may be considered good bricks.
Size and Weight of Various Materials.
|
DESCRIPTION. |
Size. |
Weight. |
||
|
ft. in. |
ft. in. |
ft. in. |
Ibs. oz. |
|
|
Stock or place brick |
0 8f |
0 4| |
0 2£ |
5 0 |
|
Paving brick . . . . |
0 9 |
0 41 |
0 If |
4 6 |
|
Dutch Clinker |
0 6£ |
0 3 |
o u |
1 8 |
|
Pantile |
1 l| |
0 9£ |
0 OA |
5 0 |
|
Bridgewater pantile |
i H |
1 7 |
0 Oi |
9 0 |
|
Plain tiles . . |
0 10£ |
0 6£ |
0 Of |
2 5 |
|
Pavement foot tile |
0 llf |
0 llf |
0 4 |
13 0 |
|
10 in. . . |
0 9f |
0 9f |
0 1 |
8 9 |
|
Pantile laths, 10 ft. bundles. |
||||
|
contains 12 laths |
120 0 |
o H |
0 1 |
4 6 |
|
Ditto ; a 12 ft. bundle con- |
||||
|
tains 12 laths . . . |
144 0 |
o H |
0 1 |
5 0 |
|
Plain tile laths, in 5 ft. |
||||
|
bundles, contains 500 laths |
500 0 |
0 1 |
0 OJ |
3 0 |
|
Thirty bundles of laths 1 load |
... |
cubic. |
||
|
A bricklayer's hod |
1 4 |
0 9 |
p*"fl |
1,296 in. |
|
A single load of sand . . |
3 0 |
3 0 |
3 0 |
27ft. |
|
A double load of sand . |
3 0 |
3 0 |
6 0 |
54 ft. |
|
A measure of lime . . . |
3 0 |
3 0 |
3 0 |
27ft. |
F 2
68
GAS ENGINEER'S POCKET-BOOK. Fire Bricks Weigh per 1000.
|
SIZES. |
Martins. |
Scotts. |
Welsh. |
|
Tns. Cts. Qr. Lb. |
Tiis. Cts. Qr. Lb. |
Tns. Cts. Qr. Lb. |
|
|
9 in. Bricks |
2 19 0 0 |
3000 |
2 17 1 0 |
|
7 in. „ |
2 11 1 0 |
|
... |
|
6 in. „ |
4620 |
... ... |
|
|
3 in. „ |
3 13 2 0 |
3 12 10 |
3 11 3 7 |
|
Side Bevels |
2 12 2 0 |
2430 |
1 17 3 0 |
|
9 in. end do. . |
2 U 0 0 |
2 11 1 21 |
... |
|
7 in. „ „ . |
1 18 1 0 |
2020 |
... |
|
F. Edge . |
1 12 1 0 |
1 13 1 0 |
16 o' 0 |
|
Arch . . . |
2 18 1 0 |
2730 |
2 15 3 0 |
|
Closers . |
1810 |
1 10 3 0 |
... |
|
2 in. Splits . . |
2200 |
2 10 2 0 |
2"'s 6"o |
|
IJin. „ |
1 17 2 0 |
1 16 0 0 |
1 15 1 0 |
|
1 in. „ . . |
1410 |
1610 |
1320 |
Resistance to Crushing.
Exposed Surface,
hquare inches.
. 39-33 .
Average Crushing '" Ight ~
40*15 — 27-9 34-85 34-76 39-94 39-94 38-28
Weight, Tons. 40 17 48 50 65 72 47 91 96
X 2f , subjected to hydraulic
Oldham red bricks . Medway gault bricks . .
„ pressed . . Stafford blue brick . . Fire-clay brick . . . Wortley blue brick . . Portland stone ... Bramley fall stone . . Yorkshire landing . . Bricks made of neat cement 9 X pressure, at the following ages : —
3 months old fractured by a pressure of 65 tons.
" J> » 5! 5> >» «** »
9 ., „ ,. „ „ 120 „
The pressure was applied in their bed, having a superficies of 38-25 square inches.
Strength of Columns of brickwork (height = less than thickness).
Crushing Commences at
Bricks, hard stocks, best quality, set in Portland cement and sand (1 to 1), 3 months old ..... 40 tons.
Bricks, ordinary well burnt London stocks, 3 months old . 30 „ „ hard stocks Roman cement and sand (1 to 1), 3 „ months old ..... 28 „
„ „ lias lime and sand (1 to 2), 6 months
old ....... 24 „
„ „ „ grey chalk-lime and sand (1 to 2). 6
months old
12 „ Herring.
BRICKWORK. 69
Brick and Stone Pillars should never be built of a height more than 12 times the thickness at base.
Where height = 24 times thickness strength is reduced to *7
?> ?> —"• "" j» ;» ?? ?> » <f*
„ =40 „ „ „ „ „ -3
Safe load should equal ^ breaking load.
Hard red bricks have sp. gr. 2-136, and will absorb 4-56 % water. Soft „ „ „ „ 1-981, „ „ 8-81 % „ Fire „ „ „ 2-000, „ „ 6-17 % „
1,000 stock bricks weigh 60| cwts.
1,000 red kiln „ „ 63 „
1,000 paving „ „ 45 „
The essential quality of a brick is hardness, and that it shall not absorb more water than one-sixth its weight. The highly vitrified brick only absorbs one-thirteenth to one-sixteenth its weight.
The characteristics of a good brick are : (1) it should be free from flaws ; (2) it should have a good ring when struck ; (3) the surfaces of the sides and faces must be level, not hollow or rounded excepting the "frog" ; (4) the surfaces must not be too smooth, or the mortar will not adhere thereto ; (5) the brick must be well burnt ; and (6) a brick should not contain any white patches nor show small stones or rough particles, when broken.
If a brick be made red-hot, and when dropped into water does not break up, it is of very good quality.
Bricks, unless of very bad quality, are not much affected by the solvent power of rainwater or the acids it holds in solution.
Analysis of a Brick Clay of Average Quality.
Silica 49-44
Alumina 34-26
Ferric Oxide .... 7!74
Lime 1-48
Magnesia 5-14
Alkalies
Water .... 1-94
100-00
English bond consists of alternate courses of headers and stretchers.
Flemish bond consists of headers and stretchers alternately in every course.
Brickwork in mortar weighs per cubic foot, 100 Ibs. „ „ cement „ „ „ 110 „
1 rod of brickwork requires 1£ cubic yards chalk lime and 3 yards sand ; or 1 cubic yard stone lime and 3£ yards sand ; or 36 bushels cement and 36 bushels sharp sand.
4,350 bricks required per rod reduced work if set 4 courses 1 foot high.
1 rod of brickwork weighs about 15 tons and contains 235 cubic feet bricks and 71 cubic feet mortar.
70
GAS ENGINEER'S TOCKET-BOOK,
L
FLEMISH BOND CORNERS.
71
|
1 |
||||||||||||||||||
|
I |
j V rt |
/ |
||||||||||||||||
|
H- |
-IK |
| |
r*, 1 ** 1 |
/ |
||||||||||||||
|
J |
TR
3 1
72 GAS ENGINEER'S POCKET-BOOK.
A bricklayer should lay 1,000 to 1,500 bricks per day in mortar (1 cement to 3 sand).
English bond gives the strongest building possible, and warehouses and other buildings in which strength is essential should be built in this style.
The rule for the thickness of walls under the Metropolitan Building Act is,
T_HL ~N 1)
Where T = thickness to be found, H = height in feet, L = length in feet, N = the constant,
D = diagonal of the face of the wall.
The constant N = 22 for dwelling-houses, 20 for warehouses, and 18 for public buildings.
Brick on edge coping should be set in 1 Portland cement to 2 or 3 sand.
1 square of pointing requires 1£ bushels sand, £ bushel lime, and small per cent, of cement.
To Preserve Scaffold Cords. — Dip when dry into a bath of 20 grains sulphate of copper per litre of water and keep in soak for 4 days, then dry. The copper salt should then be fixed in the fibres by a coating of tar ; to do this, pass the rope through a bath of boiled tar, hot, drawing it through a thimble to press back surplus tar, and suspend on a staging to dry and harden.
Scaffolding.— The putlogs or cross-pieces are generally 6 feet long, one end bearing on the ledgers and the other end resting in the wall ; upon these are placed the boards to form the stage. In scaffolding great care should be taken to see it is well braced.
Resistance to tensile strain per square inch of Mortar in Brick
joints after setting for 168 days. Common stock bricks, with masons' mortar (1 lime, 2 sand,
i smithy ashes) 27'5 Ibs.
Common stock bricks, with bricklayers' mortar (1 lime,
1 sand, 1 smithy ashes) . . . . . . 33*8 „
Firebricks, with bricklayers' mortar 28'6 „
„ „ masons' ., . . ... 24-0 .,
Masons' mortar loses about 13 % on second mixing, and bricklayers' 28%.— Bancroft.
Crushing load Crushing load per sq. inch. per sq. foot.
Portland cement 1 to 1 sand and gravel 1-18 tons 170-5 tons. „ „ 1 to 3 „ „ -81 „ 115-5 „
„ ItoG „ „ '63 „ 91-0 „
Lime and sand lose one-third of their bulk when made into mortar. Cement and sand „ „ „ .,
Sand in mortar prevents cracking, and makes it go farther ; also permits air to get to the lime while setting.
PORTLAND CEMENT. 73
Coarse is preferable to fine sand for cement mortar, up to the size that passes a sieve with 12 and is stopped by one with 16 wires to the inch. Below the grade of sand that will pass 40 and be stopped by 60 wires to the inch there is no practical difference in the value of any sands so far as the size is concerned.
The best sand for mortar should, when magnified, show a sharp angular formation, not a round or pisolite grain ; and as the porosity of a mortar affects its hardening, especially in the case of non- hydraulic limes, the size of the grains should be excessively fine.
Should be as free as possible from dirt.
Good mortar will not part easily when wet, or crumble under finger when dry.
Trap or granite sand, when sharp, appears to be the best kind of all for the purpose.
A bricklayer's hod measures usually 16" X 9", and =s 1,296 cubic inches. It will hold 20 bricks, or f cubic foot mortar (= nearly a half bushel).
Lime, or cement and sand, to make mortar, require as much water as is equal to one-third of their bulk, or about 5£ barrels for a rod of brickwork built with mortar.
Directions for using Portland Cement.
All sand, gravel, broken bricks, or other material used for making the concrete, should be clean and perfectly free from all loamy, clayey, or earthy substances whatever, otherwise failure is sure to result, notwithstanding the undoubted excellence of the cement.
Clean cold water should be used, and only just sufficient to mix to the consistency of stiff mortar. The water should be added by means of a can with a large rose, so as to spread the water evenly over the materials, the materials being thoroughly turned over and mixed while this is being done. The use of a bucket should be strictly prohibited, so as to avoid risk of deluging the concrete and washing away the cement. For stucco work only fresh water is to be used.
In order to obtain uniformity in the strength of the work, it is necessary that a thorough admixture of the cement with the other material be made — the dry mixture should be turned over twice before the water is applied, and again turned over twice in the process of wetting. No more cement should be mixed or gauged up at one time than can be used before the setting process takes place. Cement that has partially set and is mixed up again will never harden properly.
For making concrete^six to eight parts of sharp sand or clean rough gravel, to o ae of cement may be used.
For stucco work, the sand must be clean, the undercoat should be three parts of sand to one of cement, and the finishing coat, equal parts of sharp fine sand and cement, carefully avoiding mixing the mortar with too much water. The brickwork or other absorptive material on which the Portland cement is to be used must be first well wetted.
74 GAS ENGINEER'S POCKET-BOOK.
Careful attention to these directions is most essential to obtain a satisfactory result.
When making cement blocks or paving slabs, it is sometimes con- sidered advisable to steep them in a solution of sodium silicate for 10 to 14 days.
The cause of disintegration of mortar during frosty weather is the expansion due to the conversion of the water, contained in the mortar, into ice, the expansion equalling a 10 % increase in volume.
Facings and Pointing. — There is always considerable risk in using a brick for facing, unless it is known to stand the weather ; this is especially the case with red bricks. A great diversity of opinion and practice exists as to pointing. Ordinary Tuck pointing consists of well raking out the joints, filling in with coloured mortar, and then laying on a neat parallel joint with white mortar or stopping. The brickwork is also in most cases first coloured to obtain a uniform appearance.
Flat pointing is merely raking out the course joints and filling in again with blue mortar.
Lime is much improved if Portland cement is added thereto, and well mixed with it.
Eoman cement is about one-third strength of Portland cement.
Plaster of Paris.
Weight per striked bushel = 64 Ibs.
„ „ cubic foot = 50 „
The adhesive power of Portland cement is at least f of the cohesive, when new, and in time it will become fully equal to it.
L. J. Af elder and R. C. Brown.
Cement. — Magnesia causes expansion and crumbling or flaking ;
Sulphur destroys either stone or concrete. Coefficient of expansion of cement = 0-0000145
„ „ „ „ iron = 0-0000137 to 0-0000148
The Monier system of making concrete has proved itself from 5^ to 12 times as strong as that made in the ordinary way.
It has been proposed to coat ironwork which is to be imbedded in brickwork with cement, instead of asphalte or paint.
Make concrete in foundations three times as wide as the brick wall to be built upon it.
Concrete should be turned at least twice dry and twice wet. About 25 gallons water required per cubic yard concrete.
Volume of Spaces per Cent, in Concrete Materials. Limestone, crushed, to pass through 3 inch ring, 51 per cent.
!> M » 4 »l 48 -5
2* „ 36 .,
2 „ 39 ..
H ,, 42 „
Gravel, to pass through 2£ „ 34 „
RESISTANCE TO CRUSHING.
75
Shingle 33 per cent.
Thames ballast (including sand) . . . 17 „ Limestone and gravel mixed equally, to pass
through 3 inch ring 34 „
Good concrete will bear 3T6 tons per square foot in compression, and 3-16 tons per square foot in tension.
Safe Load that may be put upon a superficial foot on —
Granite piers .
Portland stone piers . . = 13 Bath stone piers . . = 6 Brickwork in cement and
sand (1 to 1) . . . = 5 Rubble masonry . . = 4 Firebrick . . . . = 6 Lias Lime (concrete
foundations) . . = 5 Ordinary brickwork in
lime mortar . . . = 3 Pine (yellow) . . = 34 Gravel or stiff clay . . = 2
= 40 tons (crushing commences at 300 tons)
90 40
40 40 50
20
24 340
Resistance to Crushing (Stones).
Per square inch. Per square foot.
Granite, average » »•-" . , 5*4 781
Limestone „ . . . . . . 3'06 441-1
Sandstone „ 1-87 268'9
Victoria stone (granite and Portland cement steeped in solution of flint), average . . 3'71 534
Ibs. per cubic in.
Crushing commences on Sandstone, strong . . . 5,000 to 9,000 „ „ „ ordinary . . 3,000 to 5,000
„ weak . . . 2,000
Limestone, compact . . 8,000 „ strong magnesian 7,000
„ weak „ 3,000
„ granular . . 4,000 to 4,500
Chalk 300 to 400
Whinstone . Granite
9,000 to 17,000
6,000 to 11,000
Mimgall.
Safe Resistance to Loads per square foot.
Rock
Chalk
Solid blue clay and gravel ....
London clay
12" X 12" wood piles, well driven to 4 blows = j" 20 to 30
13 tons. 4 „ 3 to 6 „
9
76
GAS ENGINEER'S POCKET-BOOK.
A factor of safety of one-fifth of crushing weight, if the load be dead, and of one-tenth, if the load be live, may be taken.
In laying stone the joints should be in contact from face to tail, and be thoroughly wetted on surface before laying.
The Test for the Porosity of Stone, — Weigh the stone when dry and weigh it after immersion in a pail of water. If a sandstone absorbs not more than half a gallon per cubic foot it is a good building stone.
Granite consists chiefly of quartz 50 to 60 per cent., felspar 30 to 40 per cent., mica 10 per cent. ; best with most quartz and less mica. The composition of granite is about —
Silica ..... 72-07
Alumina ..... H'81
Oxide of iron .... ,2-22
Potash ...... 5-11
Soda ..... 2-79
Lime ..... . . . T63
Magnesia ..... 0'33
Water, &c. ... . . . . 1'09
Portland Stone. — Average composition : — Silica ..... Carbonate of lime . . . Carbonate of magnesia . Iron and alumina . . . Water and loss Bitumen .....
100-00
Sandstone should consist of small grains of quartz and only small quantity of carbonate of lime and no uncombined particles of iron. Bath stone weight is 123 Ibs. per foot cube. York stone weight 156 Ibs. per foot cube.—//. Adams.
2 inch York paving weighs per square foot 26 Ibs.
2i „ „ „ , „ „ 321 .,
52
78
Covering Power of Paint.
10 Ibs. white lead .
1 oz. red lead . . . .
2 ozs. litharge
4 pints linseed oil . .
10 Ibs. white lead . 2 ozs. litharge . . . . 2£ pints linseed oil . . 1J pints spirits of turpentine
63 superficial yards, 1st coat.
100 superficial yards, 2nd coat.
PAINTS.
77
10 Ibs. white lead . . , j
' I 113 superficial yards, 3rd and 4th coats.
2 pints spirits of turpentine . j
1 pint varnish will cover about 16 square yards one coat.
100 square yards of painting, 4 coats, will require about 48 Ibs. white lead or colour paint, 4 Ibs. putty, 1\ quarts oil, 1 Ib. red lead, \ Ib. size, 2£ pints turpentine, \ Ib. pumice-stone, 1 quire glass-paper, 1 Ib. driers.
Paint should contain 1 pint turps to f gallon raw and \ gallon boiled linseed oil.
A good paint for wooden structures should consist of from 66 to 75 per cent, pigment, and the balance oil, &c.
Boiled linseed oil specific gravity should be '947 Kaw „ „ „ „ „ „ -932 to -937
„ flashpoint „ „ 500° F.
Oxide of iron paints are said to oxidize their oil and gradually destroy it.
White lead = Pb. C. 03.
The effect of sulphur upon white lead is to change the carbonate of lead into a sulphide, which becomes soluble in condensed moisture or rain-water.
To Test White Lead. — If pure carbonate it will not lose weight at 212° F. 68 grains should be entirely dissolved in 150 minims of acetic acid diluted with 1 fl. oz. distilled water.
Plumbago mixed with hot coal-tar forms a good coating for rough ironwork.
It is said that none of the metallic oxides, commonly used as pigments, chemically combine with the linseed oil in the painting mixture.
Thickness of Sheet Glass.
|
No. or Weight in ozs. per sq. ft. |
Thickness, inches. |
No. or Weight in ozs. per sq. ft. |
Thickness, inches. |
|
12 |
•059 |
21 |
•100 |
|
13 |
•or>3 |
24 |
•111 |
|
15 |
•071 |
26 |
•125 |
|
16 |
•077 |
32 |
•154 |
|
17 |
•083 |
36 |
•167 |
|
19 |
•091 |
42 |
•200 |
78
GAS ENGINEER'S POOKET-BOOK,
The Average Weight of the Materials Covering and Bearing on Hoofs, &c., may be taken roughly as follows : —
|
Description of Material. |
Weight per Foot Super. |
|
Common rafters .... |
7 Ib |
|
f-in. boarding |
91 |
|
1-m. „ Battens 3-in. by f-in. Felt . . . |
•^2 »» 3* ,, if |
|
Zinc |
a 14 |
|
Corrugated iron . |
J4 91 |
|
Slates . |
*1 |
|
Tiles . |
90 |
|
Wind | pitch about |
22 |
|
25 |
|
|
27 |
|
|
Snow .... |
5 |
|
Slate, 1 in. thick . Paving-stone, 2 in. thick . Tiles, 1 in. thick Marble, 2 in. thick .... |
15 , 28 „ 281- |
In calculating the safe load on a floor, from 1 j cwt. to 1£ cwt. per superficial foot is generally allowed for ordinary work, and from 2 cwt. to 4 cwt. for factories and warehouses, including the weight of the floor itself.
Table to facilitate the Calculation of the Area of any Roof.
|
Rise or Pitch. |
Angle. |
Proportion. |
|
|
One-sixth of span |
18 25 |
1 to 1-05 or to |
If |
|
One-quarter of span . . |
26 35 |
1 „ M2 |
1» |
|
30 00 |
1 „ 1-20 |
]i |
|
|
One-third of span . . |
33 42 |
,, 1-20 |
1| |
|
One-half of span |
45 00 |
» 1>41 |
If |
|
Two-thirds of span . . |
53 00 |
» 1-67 |
|
|
Three-quarters of span Equilateral . ... |
56 20 60 00 |
„ 1-80 „ 2-00 |
% |
|
Whole pitch . |
63 30 |
1 „ 2-83 , „ |
* |
Multiply span by the number found in the proportion column ; this gives the superficial area of the roof on the slope.
Load on roof may be taken as 50 Ibs. per foot superficial ; this includes weight of roof, and provides for extra strains thrown on it by snow, wind, <kc., from 5 to 6 tons safe load per inch of section of ties.
Slates should not be laid at less than 26 £° with horizoatal.
SLATING.
Eoof Coverings. — Roofs covered with slates or shingles should have a pitch of not less than one-fourth the width of span ; bat the roof may be truncated if a lower pitch is required.
Allowance for Wind and Snow.
Weight of snow on horizontal surface . = say, 15*5 Ibs. per sq. ft. Wind pressure on surface at right angles
to line of impact = „ 24-6 „ „
Do. do. in specially exposed positions = „ 31*0 .,
D. K. Clark.
Laths for Queens and slates should be 12 inches apart. „ Duchess and Princesses „ 10£ „ „ „ Countesses 8
Provide for removing Rainfall per Hour.
From roofs .... 5 inches in depth.
Flagged surface ... 2 „ „
Gravelled .... 0-5 „ „
Meadows, or grass plots . . 0-2 „ „
Paved surfaces ... 1 „ „
Rainfall, maximum, may be taken as 1J inches in 24 hours in cal- culating size of rain-water pipes.
|
SLATES. |
Sizes. |
Squares covered by 1000. |
Weight per 1000. |
Weight per square. |
|
Doubles |
13 in. X 6 in. |
2 |
15 cwts. |
7J cwts. |
|
Ladies . . |
16 „ X 8 „ |
*i |
25 „ |
5| „ |
|
Countesses . |
20 „ X 10 „ |
7 |
40 „ |
5f „ |
|
Duchesses . |
24 ,, X 12 „ |
10 |
60 „ |
6 „ |
To test slates, place on edge half immersed in water for 12 hours ; if water has spread up to near the top of slate, reject it ; if not risen more than \ inch, may be considered non-absorbent. Or weigh a slate before and after immersion, and the difference will show quantity of water absorbed ; should not be more than ^th part of weight of slate.
Good slates should be compact, with a metallic ring when struck, the edge not friable, incapable of absorbing or retaining much moisture hard and rough to the touch.
Weight of Zinc Slating Nails.
1 inch go about 340 to the pound. H » » 290
H „ „ 220 „
If „ „ 140
2 sj 5, 90 „
80
GAS ENGINEER'S POCKET-BOOK.
Curved roofs of 25 to 30 feet span, rise £ span may be used if 16 B.W.G. corrugated iron sheets, rivetted together with tie rods every few feet, continuous angle iron skewbacks, and thin rods from the centre, to prevent sagging in tie rods.
Use two nails to fasten each slate, say 1£ inch long, of copper. Lowest course of laths for slates should be 1 inch higher than the others.
Fall in gutters should be 1 in 50 at least.
Thick asphalted or inodorous felt is made in rolls 25 yards long by 32 inches wide.
Sheathing felt is made in sheets 32 inches x 20 inches. Dryhair „ „ , 34 „ X 20 „
No. 0, 12 oz. per sheet. No. 3, 2 Ibs. per sheet.
No. 1, 1 Ib. „ No. 4, 2£ „ „
No. 2, li Ibs. „ No. 5, 3 „ „
Willesden roofing is supplied in rolls of 50 and 100 yards X 27 inches wide (in two qualities), or 54 inches wide if required.
Allport's patent wire-wove waterproof roofing, a strong covering material made upon japanned or tinned steel wire gauze, is made in sheets 40 in. X 28 in., 42 in. X 26 in., 49 in. X 26 in. ; a lighter quality is made in sheets 42 in. x 26 in.
In laying lead, where possible avoid soldered joints.
Use not more than 10 feet sheets, and then fix roll.
Lay to a slope of not less than 1 inch in 10 feet.
Weight and Thickness of Sheet Lead.
|
Weight in Ibs. per square foot. |
Thickness in inches. |
Weight in Ibs. per square foot. |
Thickness in inches. |
|
1 |
•017 |
7 |
•118 |
|
2 |
•034 |
8 |
•135 |
|
3 |
•051 |
9 |
•152 |
|
4 |
•008 |
10 |
•169 |
|
5 |
•085 |
11 |
•186 |
|
6 |
•101 |
12 |
•203 |
Usual Thickness of Sheet Lead in use.— For aprons, 5 Ibs. per square foot ; for roofs, flats, gutters, &c., 7 to 8 Ibs. ; for hips and ridges, 6 to 8 Ibs.
Proper Proportion of Tread to Riser on Staircase, projection of Nosing not included.
Width of tread 12 inches, rise should be 5£ inches.
10* 10
PROPORTIONS OF TREADS AND RISERS.
81
Another method is to multiply the tread by the riser, both in inches, and the sums should equal 72.
Another rule —
Width of tread 6 inches, height of risers 8} inches.
7 8 9
10 H 12 13
8 71
«1 G 5 5
A further method of obtaining the Proportion of Stair Treads and Kisers —
Thus 9-inch tread requires 7-inch risers.
Stone steps upheld both ends should have 6-inch bearing at each end. „ „ • „ one end only should have 9 inches built into wall.
Timber. — Timber should never be so enclosed in a building that the air cannot circulate around it, or it will decompose. When timber has to be fixed near the ground, or in any damp place, it may be coated with a thin solution of coal tar and fish oil mixed with finely powdered clinkers from the forge.
All timber should be thoroughly seasoned before any preservative is used.
One method of preserving timber is to dry it and apply a weak solution of corrosive sublimate, or of nitric acid and water, and then paint it with white lead and oil.
Another method is to soak the timber for from 2 to 12 hours in melted napthalene at a temperature of about 200° F.
The timber used in building operations for carpenter's work is imported from Memel, Riga, Dantzic and Sweden ; and that for joiner's work from Christiania, Stockholm, Gefle, Onega and other northern ports.
In selecting timber the most convenient sizes are 12 inches square;
G.E. G
GAS ENGINEER'S POCKET-BOOK.
choose the brightest in colour, where the strong red grain appears to rise to the surface ; avoid spongy hearts, porous grain, and dead knots. (Laxtoti.*)
(1) Seasoned timber is about twice as strong as green timber ; (2) well seasoned timber loses some of its strength when moisture is re-absorbed ; (3) when free from knots and flaws timber in large pieces is as strong, per inch section, as when in smaller pieces ; (4) knots weaken timber as greatly whether it is for use as a strut or as a tie ; (5) long leafed pine is as strong as average oak ; (15) bleeding a tree does not impair the quality of its timber.
Timber joists should, where possible, be left open to the atmosphere at the ends, and not built into the wall. Iron joists should have a space at the ends to allow of expansion, and should be built in pockets.
Planks are 11 inches wide ; deals. 9 inches ; and battens, 7 inches.
Loads on Floors.
Floors of factories, workshops, and warehouses should be able to carry a load of 2^ cwt. per square foot. Floors of large buildings such as public buildings, lecture halls, churches, and chapels, should be able to carry a load of 1^ cwt. per square foot. Floors of dwelling- houses need only be strong enough to carry a load of 120 to 140 Ibs. per square foot. Basement floor joists should rest on sleepers, which should not be laid on stone.
(U.S. Assoc. of Superdts. of Bridges and Buildings.)
|
In Tension. |
In Compression. |
Shearing. |
||||
|
With Grain. |
Across. |
With Grain. |
Across. |
With Grain. |
Across. |
|
|
White Oak |
1,000 Ibs. |
200 Ibs. |
900 Ibs. |
500 Ibs. |
200 Ibs. |
1,000 Ibs. |
|
„ Pine |
700 |
50 „ |
700 , |
200 „ |
100 „ |
500 „ |
|
Red „ |
900 |
50 „ |
800 , |
200 „ |
||
|
Norway „ |
800 |
800 , |
200 „ |
|||
|
Cedar . . |
800 |
— |
800 , |
200 „ |
— |
400 „ |
|
Chestnut . |
900 |
— |
1,000 , |
250 ., |
150 „ |
400 „ |
All per square inch safe stresses.
To calculate dead distributed safe load on timber (rectangular section — floor joists, &c.) —
1,100, if fir 4 b x d? x 1.900, if oak
— = load in Ibs.
2 L
b = breadth in inches. d = depth ., „ L = span „ „
(R. A. Rule.)
A crowd of men closely packed = 120 Ibs. per square foot. A cart horse =14 cwt.
STRENGTH Of TIMBER. 8 3
Strength of Timber. (Rankine's " Civil Engineering.")
|
Wood. |
Resistance to Shearing per Square Inch in Ibs. |
|
|
Along the Fibres. |
Across the Fibres. |
|
|
Oak . . Ash and elm . Spruce or white fir Red pine |
2,300 MOO 000 500 to 800 |
4,000 |
|
Wood. |
Weight required to crush 1 Square Inch in the direction of the Fibres. |
Weight required to indent 1 Square Inch J5 inch deep across the Grain. |
|
Ash Fir (white) . Fir (yellow) Oak |
Cwt. 80 50 52 S0£ |
Cwt. 12* Bi •H 18 |
|
Pine |
3(3 |
g |
|
Wood. |
Weight required to break a Stick 1 Inch Square by Tensile Stress. |
|
Ash . |
Tons. 41 |
|
Fir (white) |
3i |
|
Fir (yellow) . Oak . |
3i 6 |
|
Pine. ... |
1 |
Time required for Seasoning. (Laslett.)
Pieces 24 inches and upward square require about Pieces under 24 inches to 20 „ „ „
»> » » 51 16 ., ,, .,
» 16 » » 12
Oak.
Months.
26
22
18
14
10
6
Fir.
Months. 13 11
9
7
5
3
G2
GAS ENGINEER'S POCKET-BOOK.
Breaking Load in Tons on Square Yellow Pine Pillars, firmly fixed and equally loaded.
6 7 8 9 ion 12
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1234567
Side of Square Pine Pillar in Inches.
STRENGTH OF PINE BEAMS.
85
Diagram showing Safe Centre Load on Yellow Pine Beams 1 Inch wide ; factor of safety, one fifth. Pitch Pine will carry one fourth more.
To find necessary width = "*ual load
load on diagram. 10" 12" 14" 9" n" 10 16" 18" 20 30 40
Feet Span.
15 20 25 3° 35
For Distributed Load multiply by 2.
86
GAS ENGINEER S POCKET-BOOK,
Distributed Safe Load on Timber Joists 1 Inch wide,
Load in Cwts. '30 20
5" 4'
Depth of Beam.
DEAD AND LIVE LOADS,
87
Average Dead Load of different Classes of Material that may have to be provided for in the Building Trade. (F. Crocker.)
Material.
Per Cubic Foot.
Slate 180 Ibs.
Lime (stone) ........ 60 „
Lime (ground) 54 „
Portland cement 85 „
Tiles 108 „
Asphalt HO .,
Brick 130
Brickwork in mortar 112
Coal 80
Concrete 130
Mud 100
Gravel 110
Masonry 140
Mortar 112
Sand 100
Snow „ . . . . ; 5 to 12
Timber (oak) j 50
„ (deal) ! 32
Water . . . ' . . . ' . . . i 62
Seeds . . . 50 „
Hay . . . .; 8 „
Straw I 4£ „
Average Weight of various Live Loads.
Description. Weight.
Man about 150 Ibs.
Crowd of men per foot superficial . . . . 86 „
„ „ densely packed 120 „
Horse (heavy) 14 cwt.
„ (light) ........ 8 „
Ox 10 „
Cow 6J „
Pig from 1 to 2 „
Sheep (small) ........ 65 Ibs.
„ (large) 90 „
Single-horse load, including horse and vehicle (heavy) 4 tons.
Pair-horse „ „ „ „ (heavy) 6£ „
Theoretical H.P. of falling water = -00189 Q.H.
Q = volume in cubic feet of water flowing per minute. H = fall of water in feet.
88 GAS ENGINEER'S POCKET BOOK.
Power of water fall (theoretically) :—
Gallons per minute x lOlbs. x height of fall in feet -f- 33,000 = II. P. Head of water in feet x -434 = Ibs. per square inch. Velocity of water in a uniform diameter cast iron pipe of smooth bore =
48 ./head in feet x diameter in feet
V lpno-1-h in fAPf
length in feet " (Hawksley.)
Quantity of water discharged from a channel or pipe =
100 sectional area of / head in feet
current in square feet V length in feet x hydraulic mean dePth-
(Downing.)
Frictional Loss in Hydraulic Rams.
(" Hicks' Formula.") F = -04 P
P = total load in Ibs.
D = diameter in inches.
F = frictional resistance in Ibs.
1 inch mercury = 13'4 inches water = 345*4 millimetres.
3^ths inch mercury = 12 inches water.
1 gallon salt water = 10-272 Ibs.
1 tou „ ., = 35 cubic feet = 218 gallons.
Specific Heat.
Specific heat = proportion of heat required to heat a substance through 1 degree compared with equal weight of water. Specific heat of water = 1.
Specific Heats.
|
Brickwork Chalk .... Charcoal . Coal (anthracite) . „ (bituminous) . Coke |
•192 •215 •241 •201 •241 •203 |
Glass . ; ' Graphite '. Ice . Stonework . Wood average . |
. -190 . . -202 . -504 . . -197 . -550 |
Speed of Sound.
In air at 0° = 1.093 feet per second. Add 2 feet for every degree Centigrade.
In water = 4,780 feet per second. In copper = 11.666 ., „ ,, In iron = 16,822 ., „ „
RADIANT HEAT.
89
Comparative Powers of Substances for Reflecting Eadiant Heat.
Lead . . . .60 Glass . . . . 10 Lampblack. . . 0
100 90
Polished brass . Silver .
Tin . . . 80
Steel . . . . 60 Table of Coefficients of Linear Expansion for 1 Degree Centigrade.
Glass =
Platinum —
Cast iron = Wrought iron =
SET :
Zinc =
Brass =
•0000085
•0000085
•00001
•000012
•000017
•000028
•00003
•000019
— idboo
1OOOOO
= 55000
68OOO
= 35000 _ . \
34OOO
= 52000
Specimens vary in their expansions, and the above Table is only approximate.
Factors of Safety, (Unvvin.)
|
Dead Load. |
Live Load. |
In Structures subjected to Shocks. |
||
|
Temporary Structures. |
Permanent Structures. |
|||
|
Wrought iron and steel Cast iron . . . Timber Brickwork . . . Masonry |
3 3 20 |
4 4 4 |
4 to 5 5 10 6 20 to 30 |
10 10 |
One B.T. unit of electricity = 1,000 watts for 1 hour. One H.P. = 746 watts.
One B.T. unit of electricity = 1| HP. very nearly. Sizes of Wire Gauges in Decimals of an Inch.
|
Size. |
Birmingham Wire Gauge. |
Imperial Standard Gauge. |
Size. |
Birmingham Wire Gauge. |
Imperial Standard Gauge. |
|
1 |
•312 |
•300 |
13 |
•093 |
•092 |
|
2 |
•281 |
•276 |
14 |
•078 |
•080 |
|
3 |
•265 |
•252 |
15 |
•070 |
•072 |
|
4 |
•234 |
•232 |
16 |
•062 |
•064 |
|
5 |
•218 |
•212 |
17 |
•054 |
•056 |
|
6 |
•203 |
•192 |
18 |
•016 |
•048 |
|
7 |
•187 |
•176 |
19 |
•042 |
•040 |
|
8 |
•171 |
•160 |
20 |
•038 |
•036 |
|
9 |
•156 |
•144 |
21 |
•034 |
•032 |
|
10 |
•140 |
•128 |
22 |
•031 |
•028 |
|
11 |
•125 |
•116 |
23 |
•028 |
•024 |
|
12 |
•109 |
•104 |
24 |
•02-") |
•022 |
90
GAS ENGINEERS POCKET-BOOK
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WEIGHT OF ONE LINEAL FOOT OF FLAT ROLLED IRON. 91
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92
GAS ENGINEER'S POCKET-BOOK.
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WEIGHT OF ONE LINEAL FOOT OF FLAT ROLLED IRON. 93
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94
GAS ENGINEER'S POCKET-BOOK.
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96 GAS ENGINEER'S POCKET-BOOK.
American and Birmingham Gauges. 1 mil. is equal to T^j inch.
|
No. |
American. Diameter in Mils. |
Birmingham. Diameter in Mils. |
No. |
American. Diameter in Mils. |
Birmingham Diameter in Mils. |
|
0000 |
4GO |
454 |
8 |
128-5 |
165 |
|
000 |
409-6 |
425 |
9 |
114-4 |
148 |
|
00 |
364-8 |
380 |
10 |
101-9 |
134 |
|
0 |
324-9 |
340 |
12 |
80-8 |
109 |
|
1 |
289-3 |
300 |
14 |
64-1 |
83 |
|
2 |
257-6 |
284 |
16 |
50-8 |
65 |
|
3 |
229-4 |
259 |
18 |
40-3 |
49 |
|
4 |
204-3 |
238 |
20 |
32 |
35 |
|
5 |
181-9 |
220 |
30 |
10 |
12 |
|
6 |
162 |
203 |
40 |
3-1 |
5-8 |
|
7 |
144-3 |
180 |
Weight of Vieille-Montagne Zinc Sheeting per Square Foot.
|
Gauge. |
Lb. |
Ozs. |
Drms. |
Gauge. |
Lb. |
Ozs. |
Drms. |
|
9 |
0 |
10 |
5 |
14 |
1 |
2 |
12 |
|
10 |
0 |
11 |
7 |
15 |
1 |
5 |
12 |
|
11 |
0 |
13 |
5 |
16 |
1 |
8 |
12 |
|
12 |
0 |
15 |
2 |
17 |
1 |
11 |
11 |
|
13 |
1 |
0 |
15 |
18 |
1 |
14 |
11 |
Thickness of Tin Plates.
|
ic = 30 B. G. ix = 28-1 ixx = 26-8 |
ixxx = 25-8 ixxxx = 24-8 IXXXXX = 23'9 |
ixxxxxx = 23-l DC == 27-8 DX = 25-6 |
DXX = 24-2 DXXX = 23-0 DXXXX = 22'0 |
Table Showing the Number of Square Feet a Cwt. of Sheet Lead will cover on a Flat Eoof or Gutter.
Thickne.^. Inch.
Weight per Square Foot.
Milled lead
- Cast lead
28 feet 0 inches. 22 „ 5 „
Specific gravity = 11 '325. Weight per cubic foot = 708 Ibs. 330 l}-inch galvanised slate nails weigh 1 Ib. 50 5-inch lead nails weigh 3 Ibs. 2| ozs.
CORRUGATED IRON.
97
To unite two pieces of lead, the surfaces to be joined are scraped bright, and between them there is immediately inserted a very thin leaf of lead amalgam — that is, lead-foil that has been saturated with mercury. On passing a soldering iron along the seam, or by heating in some other way, the mercury is vaporised and driven off. The lead is left free in an extremely fine state of division, and in that state readily fuses, and forms a sound joint between the adjacent parts.
Weight of Copper Nails. 1 inch weigh about 3 Ibs. 4 ozs. per 1,000.
H ,, „ „
9 11 29
40
16 B.W.G. Corrugated iron weighs per square
Cwt. Qrs.Lbs.
20
94.
^- r
allowing for laps.
Corrugated Iron Roof. Sheeting.
|
B. Wire Gauge. |
Size of Sheets. |
Weightier Square Foot. |
Weight per 100 Square Feet. |
Square Feet per Ton. |
||
|
Feet. |
Cwt. |
Qra. |
Lbs. |
|||
|
No. 1C) |
6 x 2 to 8 x 3 |
3-5 |
3 |
0 |
14 |
800 |
|
, 18 |
6 x 2 to 8 x 3 |
2-6 |
2 |
1 |
6 |
1,000 |
|
, 20 |
6 x 2 to 8 x 3 |
2-05 |
1 |
3 |
G |
1,250 |
|
, 22 |
6 x 2 to 7 x 2£ |
1-75 |
1 I 2 |
7 |
1,550 |
|
|
> 24 |
6 x 2 to 7 x 2^ |
1-36 |
1 |
0 |
24 |
1,880 |
|
, 26 |
6 x 2 to 7 x 2£ |
1-12 |
1 |
0 |
6 |
2,170 |
jLth weight to be added for lappnge. Relative Heat Conducting Power of Metals. Silver = 1,000.
|
Metals |
Conducting Power. |
|
Silver . Gold „ with 1 per cent, silver . . . ... Copper, rolled » cast |
1,000 982 840 845 811 677 |
|
„ with 1'25 per cent, tin Aluminium . |
412 (65 |
G.E.
98
GAS ENGINEERS POCKET-BOOK.
Eelative Heat Conducting Power of Metals. Silver = 1,000
(continued).
|
Metals. |
Conducting Power. |
|
Zinc, rolled „ cast vertically „ „ horizontally .... . . Cadmium Wrought iron . Tin .... |
641 628 608 577 436 422 |
|
Steel Platinum Sodium |
397 380 365 |
|
Cast iron Lead |
359 287 |
|
Antimony, cast horizontally „ „ vertically Bismuth Copper with 1 per cent, arsenic . . . . » » '° » »»••••• » "25 „ „ |
215 192 61 570 669 771 |
Relative Electrical Conductivity of Metals.
Silver Copper Brass Tin .
100 74 24 15
Iron Lead . Platinum Bismuth
12 8 8 2
Melting Point of Metals.
|
°F. |
Specific Heat. |
CF. |
Specific Heat. |
||
|
Aluminium |
Nickel . . . |
2,810 |
•109 |
||
|
(pure) . . |
1,300 |
•234 |
Platinum . . |
3,080 |
•039 |
|
Antimony |
810 |
•051 |
Silver |
1,832 |
•057 |
|
Bismuth . . . Brass . . . |
507 1,650 |
•031 •094 |
Steel (hard) . Steel (mild) . |
2,370 2,550 |
Vll7 |
|
Copper |
|
•095 |
Tin . |
446 |
•057 |
|
Gold . . . |
2,166 |
•032 |
Zinc . |
736 |
•096 |
|
Iron (cast) . . |
1,920 to |
•130 |
Phosphorus . . |
110 |
•288 |
|
2,012 |
Spermaceti |
120 |
|||
|
„ (wrought) |
2,912 |
•110 |
Sulphur . . |
230 |
•203 |
|
Lead . . |
612 |
•031 |
Tallow |
92 |
|
|
Manganese . . |
— |
•144 |
Wax (bees') . |
150 |
|
|
Mercury . |
- 39 |
•033 |
„ (paraffin). |
114 |
SHRINKAGE OF CASTINGS. 99
Cast iron usually consists of from 3 to 5 per cent, of carbon, which in white iron is thoroughly combined with the iron, and in grey iron 0-6 to 1-5 per cent, is combined, and the remainder crystallises separately as graphite.
Cast iron contracts ^ inch per foot ; patterns should therefore be that amount larger, or say 1 per cent.
Usual Allowance for Shrinkage of Castings per Foot.
Parts of an Inch.
For cast iron pipes . . . . -125 = |
„ „ beams and girders . . •! = ib
„ „ cylinders, large . . -094 = ^
„ „ „ small . . -06 = i
Brass -17 = &
Lead . . . . . . . -31 =
Zinc -25 =
Copper . . . . . . . -17 = A
Babbitt Metal.
Proportions of Babbitt metal for running in cast iron boxes —
1. For light work . . . 50 tin,' 5 antimony, 1 copper.
2. „ heavy „ . . . 46 ,,8 ,,4 „
Attrition Metal.
One copper, 3 best tin, 2 regulus of antimony ; heat separately and then mix and add 3 more parts tin ; on remelting add twice the quantity of tin to one of above mixture.
Delta Metal.
Cast.— Copper, 55-94 per cent. ; zinc, 41-61 per cent. ; iron, '81 per cent. ; manganese, -81 per cent. ; lead, -72 par cent. ; phosphorus, •013 per cent. ; nickel, a trace.
Wrought. — Copper, 55-8 per cent. ; zinc, 40-07 per cent. ; lead, 1-82 per cent. ; iron, 1-28 per cent. ; manganese, -96 per cent. ; phosphorus, -Oil per cent. ; nickel, a trace.
Rolled. — Copper, 55*82 per cent. ; zinc, 41-41 per cent. ; manganese, 1'38 per cent. ; iron, -86 per cent. ; lead, -76 per cent. ; nickel, "06 per cent. ; phosphorus, a irace.
Hot-punched Metal.— Copper, 54-22 per cent. ; zinc, 42-25 per cent.; lead, 1-1 per cent. ; manganese, 1'09 per cent. ; iron, -99 per cent. ; nickel, -16 per cent. ; phosphorus, -02 per cent.
Tensile strength of cast = 35 tons per square inch.
i» M » forged = 42 „ „ „ „
Will not weld, but can be soldered.
H2
100
GAS ENGINEER'S POCKET-BOOK.
To Case harden. — Make the surface bright, heat to red heat, rub with prussiate of potash, and quench in water. Or, better, heat the iron in a close box filled with boiie dust and (
(Unwin.)
cuttings of horn and leather.
Colours and Temperatures for Hardening Tools.
Pale straw = 430°F. for lancets, &c.
Dark yellow = 470°F. „ razors.
„ straw = 470°F. , penknives.
Clay yellow = 490°F. , chisels and shears.
Brown „ = 500°F. , adzes and plane irons.
Very pale purple = 520°F. table knives.
Light purple = 530°F. swords and watch springs.
Dark „ = 550°F. softer swords and watch springs.
„ blue = 570°F. small fine saws.
Blue = 590°F. large saws.
Pale blue = 610°F. saws, the teeth of which are set
with pliers.
Greenish blue = 630°F. „ very soft temper.
STRENGTHS AND MODULUS OF ELASTICITY.
101
1 1 1 1 1 1 i" 1 1 1 i 1 1 1 § I § i § If 1 1 1 1 1 1 1 1 § §f
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0-M =
aj > 42
102
GAS ENGINEER'S POCKET-BOOK.
PROPORTIONS OF BOLTS AND NUTS. (Uiiwin.)
Hexagon Nuts.
Diameter across flats = D = I' nil + O'lS to I'od -f 0'44 if rough.
„ „ „ = I'od -f 0-06 to I-od + 0 18 if bright.
„ „ angles = Dx= I'7od + O'Ui to l'7»d + 0'4 if rough.
= I'7od -f 0-07 to I'lU + 0-2 if bright.
Height of nut = d = diameter of bolt.
d „ „ lock nut = Y
Square Nuts.
Diameter across flats = I.od + 0-18 to I-od + 0-44 if rough.
., „ „ = I'od -f O'OG to I'od + 0'18 if bright.
„ ., angles = 2'12d + 0-25 to 2-12^ + 0-6 if rough. „ ,, = 2-I2d + 0-08 to 2ri2^ + 0-25 if bright.
Head of bolt may be square, hexagonal, or circular. Its height fd to d'
Washers.
Thickness, O'lorf ; diameter |Dr
Small washers are usually 14 B.W.G. or 0'083 inches thick. Washers for wood may be 3d in diameter and Q'3d in thickness.
Length of spanner = lod to I8d.
A workman exerting a pull of 301bs. on a spanner will cause tension in the bolt = 2.4G01bs., a force enough .to break a f inch bolt, and to seriously strain a £ inch bolt. Therefore bolts of less than | inch diameter should not be used for joints requiring to be tightly screwed up.
Number of Cold-punched Nuts per 100 Lbs.
|
Inch. |
Square. |
Hexa gon. |
Inch. |
Square. |
Hexagon. |
|
f |
1.951 |
3,020 |
1 |
109 |
100 |
|
i |
812 |
800 |
1* |
81 |
83 |
|
• |
428 |
444 |
if |
65 |
62 |
|
£ |
248 |
261 |
34 |
31 |
|
|
I |
165 |
165 |
Weight in Lbs. of Nuts and Bolt Heads.
|
Diameter of Bolt in Inches. |
|||||||||||||
|
Head and Nut. |
i |
1 |
i |
1 |
1 |
1 |
1 |
H |
H |
If |
2 |
2J |
3 |
|
Hexagon |
•017 |
•057 |
•128 |
•207 |
•43 |
•73 |
1-1 |
2-14 |
3-77 |
5-62 |
8-75 |
17-2 |
28'8 |
|
Square. |
•021 |
•070 |
•164 |
•321 |
•553 |
•882 |
1-31 |
2-56 |
4-4-2 |
7-00 |
10-5 |
21-0 |
36-4 |
BOLTS, NUTS, AND WASHERS.
103
Weight of Wrought Iron Hexagon Bolt Heads and Nuts,
inch = -0171b3.
„ = -059 „
„ = -137 „
= -267 ,
(Another Rule.)
inch = -461 Ibs. „ = '73 „ „ =1-09 „ » =2-13 „
li inches = 3'6S Ibs. If „ = 5-86 „ 2 =8-74 ,
Weight of Washers per 100.
§ inch = If Ibs. | inch = 6| Ibs. 14 inch = 18| Ibs.
1 __ o i 7 Q i it __ fyt
2 » — ^2 » 8 » ~ °2 ?> 1? » — ** M fi II i tr\r-i 11 _OA
•••2 » ^^4. j] -» a »
Strength of bolts — allow a factor of safety of
30 „
8.
Strength of Bolts. (Unwin.)
|
Diameter of Bolt. |
Strength when there is no stress due to screwing up. |
Pull on Spanner. |
Stress due to screwing tip. |
Effective Strength when screwed up against an Elastic flange. |
|
Inches. |
Lbs. |
Lbs. |
Lbs. |
Lbs. |
|
i |
1,008 |
16 |
1,312 |
_— |
|
i |
1,830 |
18 |
1,476 |
360 |
|
1 |
2,736 |
20 |
1,640 |
1,096 |
|
I |
3,798 |
23 |
Ij890 |
1,908 |
|
i |
4,98f> |
25 |
2,050 |
2,936 |
|
H |
6,273 |
27 |
2,214 |
4,069 |
|
if |
8,046 |
29 |
2,380 |
6,666 |
|
if |
10,044 |
32 |
2,624 |
7,420 |
|
11 |
11,700 |
34 |
2,790 |
8,910 |
|
i| |
15,750 |
39 |
3,200 |
12,510 |
|
2 |
20,790 |
43 |
3,530 |
17.260 |
|
21 i 27,180 |
47 |
3,940 |
23,240 |
|
|
2^ |
33,570 |
52 |
4,260 |
29.310 |
|
2| |
41,760 |
57 |
4,670 |
37,090 |
|
8 |
48,870 |
61 |
5,000 |
43,870 |
|
»i |
58,590 |
65 |
5,350 |
53,240 |
|
3i |
68,310 |
70 |
5,740 |
62,570 |
|
8| |
79,740 |
74 |
6,100 |
73,640 |
|
4 |
90,090 |
79 |
6,500 |
93,590 |
|
5 |
136,080 |
97 |
7,950 |
128,130 |
|
6 |
212,760 |
115 |
9.450 |
203,310 |
rot
GAS ENGINEER'S POCKET-BOOK.
Proportion of Riveted Joints.
Single Lap Joints. Iron Plates and Rivets, and Steel Plates and Rivets.
|
Thickness of |
Diameter of Rivets. |
Pitch of Rivets. |
Centre of Rivets to Edge of Plates. |
|||
|
Iron. |
Steel. |
Iron. |
Steel. |
Iron. |
Steel. |
|
|
Inch. |
Inch. |
Inch. |
Inches. |
Inches. |
Inch. |
Inch. |
|
4 |
i f |
1 |
11 |
l| |
itt |
H 14 |
|
7 |
lo5 |
a |
2 2 |
2 2 |
i| |
if |
|
A |
a |
i |
2* |
2J |
ITO |
14 |
|
1 |
iiV |
H |
2* |
1J |
14 |
|
|
F |
if |
2* |
Ja |
is |
Double Lap Joints. Iron Plates and Rivets, and Steel Plates and Rivets.
|
Distance between rows |
|||||||||
|
Thick- ness of |
Diameter of Rivets. |
Pitch of Rivets. |
Centre of Rivets to edge of Plates. |
of Rivets. |
|||||
|
Zigzag. |
Chain. |
||||||||
|
Plates. |
|||||||||
|
Iron. |
Steel. |
Iron. |
Steel. |
Iron. ; Steel |
Iron. |
Steel. |
Iron. |
Steel. |
|
|
... In. |
• In. |
In. |
Ins. |
Ins. |
In. In. |
In. In. |
Ins. |
Ins. |
|
|
i7* |
I |
% ' 2* |
2fl |
H 1£ |
If |
If |
2 |
24 |
|
|
i |
a |
2J |
2^ H 1^ |
}J |
rf |
24 |
24 |
||
|
£ |
! |
iS » |
2{i 1^ I H |
4 |
1* |
24 |
2f |
||
|
K |
a |
1 |
3J |
8 |
if i H |
ij |
H |
2| |
2^ |
|
f |
i }i |
1} |
84 4 |
8* 4 |
n i& If i Itt |
if 113 w |
itt if |
H N |
2| 2:1 |
|
1 |
i* |
H |
N |
»i |
if n |
4 |
MI |
2J |
3 |
RIVETED JOINTS.
105
Proportion of Riveted Joints — continued.
Single Riveted Double-butt Joints. Iron Plates and Rivets, and Steel Plates and Rivets.
|
Thickness of |
Diameter of Rivets. |
Pitch of Rivets. |
Centre of Rivets to Edsje of Plate. |
Thickness of Butt Strap. |
||||
|
Plates |
||||||||
|
Iron. |
Steel. |
Iron. |
Steel. |
Iron. |
Steel. |
Iron. |
Steel. |
|
|
Inch. |
Inch. |
Inch. |
Inches. |
Inches. |
Inch. |
Inch. |
Inch. |
Inch. |
|
I |
i |
9 |
HI |
If! |
y |
i* |
i |
i |
|
^3 |
y |
I |
2* |
2£ |
i$ |
ll |
i |
i |
|
i |
& |
2ft |
2ft |
H |
ii |
& |
4 |
|
|
Tli |
i |
i |
2ft |
2* |
H |
ITS« |
i |
|
|
% |
i 8 |
a |
2^ |
2* |
>i |
if |
1 |
t |
|
y |
tf |
i |
2}o- |
21 |
lj |
il |
7 10 |
7 10 |
|
i |
1 |
14 |
2g |
2* |
H |
il |
V, |
|
|
i |
H |
IT'O |
2 |
3 |
iti |
iy |
9 10 |
a To |
Double Riveted Double-butt Joints. Iron Plates and Rivets. Steel Plates and Rivets.
•
Diameter of Rivets.
Pitch of Rivets.
Centre of Distance between Rows
Rivets to Edge of Plates.
Iron. Steel. Iron. ! Steel. Iron. Steel.
In. i In. f
y
In. Iii.
In. !
In.
jl 4
of Rivets.
Zigzag.
Iron.
Steel.
In. H If
28 2f6
Chain.
Iron.
Steel. In.
Thickness
of Butt Strap.
Iron.
In.
Steel.
Riveted Joints. — Ultimate resistance to shearing
= 22 tons per square inch of rivets if wrought iron. = 30 to 40 tons per square inch of rivets if steel. Bolts. — Head's should be at least *7 times the diameter of screwed ends of bolts.
Nuts. — Should be at least -S3 times the diameter of screwed ends of bolts.
Table of Ultimate Single Strength of Rivets.
|
Diameter. |
Tons. |
Diameter. |
Tons. |
Diameter. |
Tons. |
|
£ inch |
•246 |
5 inch |
6-16 |
1$ inch |
20 |
|
A „ |
•986 |
1 „ |
8-88 |
U „ |
24-6 |
|
1 „ |
2-22 |
1 „ |
12-1 |
If „ |
29-8 |
|
\ „ |
3-94 |
1 „ |
15-8 |
106
GAS ENGINEER'S POCKET-BOOK.
If the rivet is in double shear it will have double the strength shown in table, i.e.
If a butt joint has two cover plates — one each side.
Weight of Rivet Heads (actual). Two 1-inch rivets (heads only) = 9f ounces
Weight of Eivet Heads.
No. 10 rivet heads, 1 inch diameter = 2*7 Ibs.
7 _ 9.9
» » 8 M H — * ^ 55
3 _ 1 .K
» » 4 »> » — -1 ° »
I „ ,, =0-9 „ (W.I.G.)
Diameter of Rivets for Plates of Different Thicknesses.
|
Thickness of Plates = t. |
Diameter of Rivets = d. |
Diar. of Rivets after Riveting = l'04d. |
|
|
Inches. |
Inches. |
||
|
i |
o-oo |
JL |
0-624 |
|
t |
0-67 |
5 |
0-72 |
|
0-73 |
I |
0-78 |
|
|
ia |
0-79 |
a |
0-85 |
|
\ |
0-85 |
0-91 |
|
|
ire |
0-90 |
^ |
0'91 |
|
| |
0-95 |
15 |
0-97 |
|
1-04 |
Ijg |
MO |
|
|
£ |
1-12 |
I* |
1-17 |
|
1 |
1-20 |
1-24 |
Resistance to Shearing.
When rivets fit the holes exactly, shearing stress = P — area of cross-section.
If the section is rectangular, and pressure perpendicular to one
side, —i
If the section is circular or elliptical, and pressure perpendicular
to one side, = 4
3 a If the section is square, and pressure acts parallel to a diagonal,
= ^_Z 8 a
STEENGTH OP RIVETED JOINTS.
107
Resistance to Torsion.
m . ' 12 x 33,000 x HP.
Twisting moment = - — — — —
Resistance to twisting = Shearing stress x Z^ Zt for cylindrical bars = 0'196 ds
Z, ., hollow do. do. = 0-196 d^ ~ 2 * «i
Z, „ square bars = 0*208 side3
Average Proportions of Rivets to Diameter of Hole. The shearing resistance of steel rivets is little greater than of rivet iron, owing to its necessary soft quality.
Small rivets for plates less than § inch, thick may be riveted cold. Strength of Riveted Joints to Plates.
|
Joint. |
Riveting. |
Cover Straps. |
Pitch of Rivets. Diameters. |
Strength of Joint to Plate. |
|
Lap |
Single |
— |
3d |
•65 |
|
Butt |
" |
1 |
3d |
•55 |
|
M |
Jl |
2 |
3-25rf |
•57 |
|
Lap |
Double |
— |
4-od |
•69 |
|
Butt |
»» |
1 |
4-5^ |
•69 |
|
?> |
;? |
2 |
5-5d |
•72 |
Shearing resistance of iron or steel bars = |ths their tenacity. Rivet iron, shearing resistance, in Ibs., per square inch 49,(>00 ., steel „ „ ., „ ., 52,800
Values of Riveted J oints and Apparent Tenacity in Lbs. per Square Inch.
|
Iron Plates. |
Steel Plates. |
Plates |
Steel Plates. |
|
|
Single riveted, drilled . |
0-88 |
i-oo |
40,500 |
62.000 |
|
., ., punched ! 0-77 |
0-90 |
35,400 |
55.SOO |
|
|
Double „ drilled . |
0-95 |
1-06 |
43,700 |
65.700 |
|
„ .. punched |
0-85 |
1-00 |
39.000 |
62.000 |
|
Treble „ drilled . |
— |
1-08 |
45,000 |
67,000 |
lakmg iron at 46,000 Ibs. per square inch, and steel at 62,000 Ibs.
108 GAS ENGINEER'S POCKET-BOOK.
Apparent Shearing Resistance of Rivets in Riveted Joints. (Unwin.)
Iron rivets in punched holes ... 10,000 Ibs. per square inch.
„ drilled ., ... 43,000 ., „ .,
Steel „ punched ., ... 53,OUO ., !, I,
„ „ drilled „ ... 49,000 „ „ j-
Proportions of Rivets.— The height of a finished snap-head should be from §ths to fths the diameter of shank. Allowance in length necessary for this = 1 J times the diameter ; in machine riveting add $th to |th more. Allowance for countersunk riveting = diameter of shank.
Strength of double riveted joint = 70 per cent.
„ single „ ., = 56 ., (Herring.)
Diameter of rivets in plates under £ inch thick should be twice the thickness of the plate.
Diameter of rivets in plates above £ inch thick should be 1£ times the thickness of the plate.
Proportion' of rivets to thickness of plate diameter = T2 V thickness of plate. (Unwin.)
Advantage of machine riveting is that the rivet is still hot when the head is finished.
Pressure on rivets by machine = about 25 tons.
Holes in iron should be punched, and afterward drilled out 'th inch larger to prevent starring and damage to the surrounding metal, or drilled full size — in all girder work.
Rivets are not considered reliable in tension.
The best way with steel plates is to anneal them after punching if of i inch to f inch thickness, or the holes rimered after punching. Above this thickness all plates should be drilled.
The sharp square edge of a drilled hole is not likely to add any strength to the rivet, but rather the reverse.
If the plates through which a rivet is to be passed are more than 6 inches in all it is distinctly better to use bolts.
The old plan of driving a conical drift into the rivet holes is an objectionable method of ensuring agreement, as it injures the plates, but if the holes are rimered when in position the punched hole is improved in strength.
With very soft, ductile plates, it is believed that the injury done in punching is comparatively small if the punch be sharp. But with rigid plates the injury is apparently serious, the plates being weakened 15 per cent, to 30 per cent. (Unwin.)
To fill up the hole and form a head, from 1-3 to 1-7 times the diameter should be allowed in ordinary riveting, and about three- fourths the diameter if countersunk rivets are to be used.
Machine riveted work is slightly stronger than hand work.
STRENGTH OF ROPES AND CHAINS.
109
fc!
•3
4
00
3 £
111
I I I
<M t^ <M O t- JO
its
fH i-l (M <M CC CO
110 GAS ENGINEER'S POCKET-BOOK.
Strength and Weight of Hemp and Wire Ropes.
|
TARRED ITALIAN HEMP. HAWSER LAID. |
WIRE ROPE. HAWSER LAID. |
||||
|
Circum- ference. |
B. W. |
Weight of One Fathom. |
Iron B. W. |
Steel B. W. |
Weight of One Fathom. |
|
Inches. |
Tons. |
Lbs. |
Tons. |
Tons. |
Lbs. |
|
| |
•11 |
•15 |
|||
|
1 |
•17 |
•221 |
|||
|
1 |
•30 |
•3 |
1-0 |
|
•94 |
|
H |
•89 |
•43 |
1-35 |
— |
1-5 |
|
1* |
•94 |
•57 |
2-15 |
6-25 |
2-5 |
|
2 |
1-44 |
•93 |
4-0 |
11-2 |
3-5 |
|
2* |
— |
— |
5-0 |
|
4-5 |
|
2* |
2-16 |
1-5 |
6-0 |
19-5 |
5-75 |
|
2f |
— |
— |
7-73 |
— |
6-5 |
|
3 |
3-0 |
2-02 |
9-2 |
24-5 |
7-5 |
|
g* |
— . |
— |
10-93 |
27-5 |
8-5 |
|
3£ |
4-2 |
2-9 |
12-5 |
45-0 |
10-75 |
|
4 |
5-6 |
3-8 |
15-75 |
54-5 |
13-25 |
|
4J |
6-75 |
4-7 |
21-0 |
GG-87 |
17*75 |
|
5 |
8-0 |
6-0 |
24-8 |
— |
21-5 |
|
5J |
11-0 |
7-1 |
30-0 |
83-0 |
26-5 |
|
6 |
14-25 |
8-5 |
36-2 |
100-0 |
31-5 |
|
6| |
16-1 |
10-0 |
42-75 |
40-6 |
|
|
7 |
20-6 |
11-7 |
48-35 |
— 42-5 |
|
|
7* |
21-75 |
13-3 |
55-0 |
4(v75 |
|
|
8 |
25-75 |
15-0 |
59-0 |
|
51-75 |
|
8.1 |
28-0 |
17-0 |
65-33 |
— |
58-42 |
|
9 |
30-5 |
19-0 |
|||
|
9* |
33-75 |
21-3 |
|||
|
10 |
36-0 |
23-6 |
|||
|
IQi |
38-9 |
26-0 |
|||
|
11 |
42-0 |
28-5 |
|||
|
U| |
45-1 |
30-0 |
|||
|
12 |
48-5 |
34-0 |
STRENGTH OF ROPES AND CHAINS. Bound Ropes of Iron and Steel Wire. (R. A. Rule.)
Ill
|
Circum~ |
IRON WIRE. |
STEEL WIRE. |
|||
|
ference in Inches. |
per Fathom in Ibs. , |
Safe Load in |
Breaking Load in |
Safe Load in |
Breaking Load in |
|
Tons. |
Tons. |
Tons. |
Tons. |
||
|
1 |
1 |
0-33 |
ro |
0-83 |
2-5 |
|
H |
1-5 |
0-58 |
1-75 |
1-25 |
3-75 |
|
2 |
0-7 |
2-1 |
2- |
6 |
|
|
22 |
4 |
1-25 |
3-75 |
333 |
10 |
|
2i |
6 |
1-86 |
5-6 |
5-33 |
16 |
|
3 |
8 |
2-95 |
8-85 |
8- |
24 |
|
H |
11-5 |
3-88 |
11-65 |
10-66 |
32 |
|
4 |
15-5 |
4-92 |
14-75 |
13-33 |
40 |
|
41 |
19 |
6-55 |
19-65 |
17- |
51 |
|
52 |
23 |
7-73 |
23-2 |
21- |
63 |
|
51 |
28 |
936 |
28-1 |
25-33 |
76 |
|
62 |
34 |
11-32 |
33-95 |
30- |
90 |
|
ftj |
40 |
13-3 |
40-0 |
35-33 |
106 |
|
7 |
46 |
15-1 |
45-3 |
41 |
123 |
Steel wire ropes are usually made from f to § inch diameter, but can be had up to 3 inches diameter. When made with a hempen core they are more pliable, and for that reason more generally adopted for the purpose of transmitting power, when the wire rope takes the place of the leather straps which are more usually employed. One advantage of the use of rope gearing is the greater distance over which the power can be transmitted.
In testing steel cables, the result will only equal about 75 per cent, of the aggregate strength of the individual wires.
Safe working strain in tons of iron chains = (diameter in eighths of inches)3 10
Weight in Ibs, per fathom of iron chain = (diameter in eighths of inches)2
Safe working strains in tons of rope = circumference*
Weight in Ibs. per fathom of tarred rope —
White rope is about \ lighter.
8 circumference3
Safe Working Loads in Iron Chains.
Diameter. | inch
Load. Tons. Cwts.
0
14 16
0 10
Diameter. 1 inch If
Load. Tons. Cwts.
7 0
9 0 11 0 13 0
112
GAS ENGINEER'S POCKET-BOOK.
Approximate Strength of Chains.
The square of the diameter in eighths = the weight of chain in Ibs. per fathom.
The square of the diameter in eighths divided by 2 = breaking weight in tons. Safe load = J. ( F. llogers.)
Temperature of iron when welding.— 1,500 to 1,000° F.
Strains in Hopes round Pulleys. (R. A. Tests.)
Two treble blocks used. Weight lifted = 59 cwt. 109 Ibs.
|
Position where Strain is taken. |
Strain. |
Holding after Lowering. |
|
|
Raising. | Lowering. |
|||
|
Free End. |
15'37 |
5-91 |
6-62 |
|
1st return 2nd , 3rd , 4th , 5th , Gth , |
13-28 120 10-o7 9-7 8-7 6-105 |
7-10 8-42 9-42 10-56 12-28 13-56 |
7-84 8-84 9-60 10-56 11-77 12-0 |
|
Total, excluding free end |
00-45 |
61-34 |
60-61 |
The free end has no share in supporting the weight.
When a weight is being raised, the strain on the running end is greatest, the sum of all the friction being at that end, and on the standing end least. When the weight is being lowered the reverse is the case.
Safe Working Loads on Hemp Ropes,
|
Circumference. |
Load. |
Circumference. |
Load. |
||||||
|
1 inch = |
If cwt. |
5} |
inches |
= |
2 tons 14 |
cwt |
|||
|
\i z= |
4 |
6 |
5» |
— |
3 „ 4 |
.? |
|||
|
2 „ - |
7 |
M |
55 |
= |
3 „ 15 |
j '» |
|||
|
— |
H |
7 |
» |
r= |
A. |
J M |
|||
|
32 |
— |
16 |
U |
)> |
— |
5 |
0 |
»> |
|
|
3£ |
= |
21 |
8 |
5J |
— |
5 |
14 |
If |
|
|
4 |
— |
28 £ |
8k |
?» |
= |
6 |
7 |
,, |
|
|
4J |
= |
36 |
9 |
!> |
= |
7 |
1 |
?) |
|
|
5 |
— |
44i |
Testing Iron and Steel. — If a fracture of iron gives long, silky fibres of a leaden grey hue, the fibres cohering and twisting together
TESTING
before breaking, it may be considered a tough soft iron. A medium, even grain mixed with fibres is a good sign. A short blackish fibre indicates badly-refined iron. A very fine grain denotes a hard, steely iron, apt to be cold-short and hard to work with a file. Coarse grain, with brilliant crystallised fracture, and yellow or brown spots, denotes a brittle iron, cold-short, working easily when heated. This iron welds easily. Cracks on the edge of bars are a sign of hot-short iron. Good iron is readily heated soft under the hammer, and throws out but few sparks. Nitric acid will produce a black spot on steel ; the darker the spot the harder the steel. Iron, on the contrary, remains bright if touched with nitric acid. Good steel in its soft state has a curved fracture and a uniform grey lustre ; in its hard state, a dull, silvery, uniform white. Cracks, thread, or sparkling particles denote bad quality. Good steel will not bear a white heat without falling to pieces, and will crumble under the hammer at a bright rel heat, while at a middling heat it may be drawn out under the hammer to a fine point. (" Journal of Gas Lighting.")
Contraction at point of fracture should be about 10 per cent, for plates, 15 per cent, for T and L iron, and 20 per cent, for round or square bars. (Kirkaldy.)
Iron or steel subjected to stresses above half their ultimate strength are permanently disabled.
Breaking strength equals 39 (1 + C.2) tons per square inch (C. = per cent, of carbon). (Bauschinger.)
In calculating the weight of metals up to 100° C., the temperature can be omitted as the difference is so small (TT^). An iron rod one square inch in section exerts a force of one ton, by contraction in decreasing in temperature 9° C.
Wrought iron increases TirW of its length for every ton per square inch of tension up to the limit of elasticity. (Unwin.)
The expansion due to a tension of one ton per square inch is pro- duced by a rise in temperature of from 12° to 15° F., according to the quality of the iron. Wrought iron expands by heat T^th more than cast iron, while tension causes twice as much stretch in cast iron as in wrought iron when within the elastic limit.
27° F. increase or decrease of temperature causes an expansion or contraction, equals a stress of one ton per square inch, if the metal be fixed at each end.
Strength of wrought iron and steel increases with a rise of temperature up to about 500° F., beyond which point the metals become plastic and will flow under almost any strain. (Professor R. C. Carpenter.)
The tensile strength of steel diminishes as the temperature increases from zero until a maximum is reached between 200° and 300° F. ; the total decrease being about 4,000 Ibs. per square inch in the softer steels, and from 6,000 Ibs. to 8,000 Ibs. in steels of over 80,000 Ibs. tensile strength. From this minimum the strength increases up to 400° to 650° P. ; the maximum being reached earlier in the harder steels, and the increase amounting to from 10,000 Ibs. to 20,000 Ibs. per square inch above the minimum strength at from 200° to 300° F. (J.E.Howard.)
G.E. T
114
GAS
POCKET-BOOK.
Effect of Temperature on the Strength of Steel and Wrought Iron.
Taking the initial temperature at 0° C., with an increase of tempera- ture of 200° C., the strength of wrought iron is reduced 5 per cent.
At 300° Cent. 10 per cent. „ 400 „ 27 „ „ 500 62
At 000° Cent. 81 per cent. „ 800 „ 89 „ „ 1,000 „ 96 „
The ratios between cast iron, wrought iron, and steel are 13 '3 4, 10, and 10'7 respectively.
Diminution of Strength of Copper by Heat. (Franklin Institute.)
|
Temperature above 3:2 degrees. |
Diminution of Strength. |
Temperature above 32 degrees. |
Diminution of Strength. |
|
Degrees. |
Degrees. |
||
|
90 |
0-0175 |
660 |
0-3425 |
|
180 |
0-0540 |
769 |
0-4389 |
|
270 |
0-0926 |
812 |
0-4944 |
|
360 |
0-1513 |
880 |
0'5581 |
|
450 |
0-2046 |
984 |
0-6691 |
|
460 |
0-2133 |
1000 |
0-6741 |
|
513 |
0-2446 |
1200 |
0-8861 |
|
529 |
0-2558 |
1300 |
1 -0000 |
Weight of Cast Iron Pipes.
In Ibs. per lineal foot. The weight of two flanges or one socket may be reckoned weight of 1 foot : —
|
THICKNESS OK METAL. |
||||||||
|
Bore |
||||||||
|
1 |
i 3 |
1 |
-I |
1 |
l |
H |
I* |
|
|
Inches. |
||||||||
|
2 |
8-7 |
12-3 |
16-1 |
|||||
|
3 |
12-4 |
17-1 |
22-2 |
|||||
|
4 |
16-1 |
22-1 |
28-3 |
|||||
|
5 |
19-8 |
26-9 |
34-4 |
42-3 |
||||
|
6 |
23-4 |
31-9 |
40-6 |
49-7 |
||||
|
7 |
27-1 |
36-8 |
46-7 |
56-8 |
||||
|
8 |
30-8 |
41-6 |
52-8 |
64-3 |
||||
|
9 |
34-4 |
46-0 |
58-9 |
71-7 |
||||
|
10 |
— |
51-4 |
65-1 |
79-0 |
93-3 |
CAST IRON PIPES.
115
Weight of Cast Iron Pipes — (continued').
In Ibs. per lineal foot. The weight of two flanges or one socket may be reckoned weight of 1 foot :—
|
THICKNESS OF METAL. |
||||||||
|
Bore |
||||||||
|
Inches. |
i |
i |
i |
1 |
i |
1 |
n |
H |
|
11 |
5<V4 |
71-0 |
86-4 |
101-8 |
||||
|
12 , _ |
|
77-3 |
93-7 |
110-4 |
127-4 |
|||
|
H |
|
|
89$ |
108-4 |
127-5 |
147-0 |
||
|
15 |
|
|
|
115-7 |
13()-1 |
15(5 -8 |
||
|
1<> |
|
|
- |
123-1 |
144-7 |
16(i-(5 |
||
|
18 |
|
|
|
137-9 |
1G1-8 |
18(5-2 |
||
|
20 |
|
|
|
|
178-9 |
205-8 |
2<>0-3 |
|
|
22 |
|
|
|
|
|
225-4 |
284-8 |
|
|
24 |
— |
— |
— |
— |
245-0 |
309-3 |
All cast iron pipes above 0 inches diameter should be cast on end, spigot up, and about 4 or 6 inches cut off afterwards in a lathe to remove the spongy portion.
Rule for the Weight of Pipes. (Molesworth.)
D = outside diameter of pipes in inches.
d = inside ., „ „
iv — weight of a lineal foot of pipe in Ibs.
w = k (D2 - da).
k = 2-45 for cast iron = 2'64 for wrought iron = 2'82 for brass = 3-03 for copper = 3'86 for lead.
116
GAS ENGINEER'S POCKET-BOOK.
|
2 <M |
«(XM|tHN t- CN CC r-( <M i-H |
|
_g o |
HtH» l> iM CC i-l (M r-t |
|
.2* Ci |
tC <M CO 1— 1 (M l-H |
|
.a CO |
o o N l-H <M l-H |
|
.2' t~ |
HM Ha -1" Cl i— I |
|
.s to |
4< cc'^T |
|
a »n |
«ixH» CC I- O |
|
-*5 |
~H- H2»w CC «C O5 i— 1 r-( |
|
d -t< |
mi-* f-H tC OS |
|
d MX cc |
H» ~IM -H- i— i -* t- |
|
.9 CO |
H— MH> <N ^ OC |
|
JO HN gq |
HM Ht o -* to |
|
.S <M |
HN CS <M tO |
|
n |
HN 00 i-l <O |
|
d |
cc o o |
|
£ Ht |
»4N«4« to ct -H |
|
^fl i— | |
wit -It »~ OS ^ |
|
.2 «« |
-Irf 1~ n •** |
|
Diameter |
<JPQ« |
|
.S «M |
-N1 -IN Ha "* >^ O r-l C<1 r-l |
|
_rt o |
Ml^wlceHso (M CO GO i-t <M |
|
q Q) |
Hxosjeo-H* (M I-H CO r-l (M |
|
2 CO |
«1XWM.*|2 (M Oi CO |
|
c t^ |
OS Ci i^ |
|
d 0 |
HtHtHee CO ri ti (N |
|
jj |
t» e*1** |
|
g HM •JJ |
«!oo CO ->C iO |
|
d •ti |
MH- l> •<# •* i— I |
|
0 HM CO |
HN mlf r^ •* CO |
|
•1 .2 -IN <M |
«!2 «^» to ec n PH eJht-lM-H1 l-t (M OC |
|
Q N |
mteHMwhi IS --I (N |
|
d |
•4+HN >A l-H (M l-H |
|
^c -IN |
HNH»Ht -* l-H (M |
|
d «it |
HN-lt to c; ^ |
|
d |
RiS*-* |
|
.2* «]* |
-It »rj C5 •* |
|
Diameter |
<^?Q« |
|
.2 (M |
-It H« •«** to •* r-i i-H S<| |
|
_C O |
-It HN ^2cg |
|
_c C5 |
«!S»itH» CC i-l -ti i-l »M ^1 |
|
G CO |
HN-ltmHi M -H>l O I-H l-H CM |
|
c t^ |
*«»!* «',2 c cc tc |
|
_c v |
HN n|x 'C,M O M l^ |
|
.2' >n |
HN wit <iX O i-c l^ |
|
_C HN -tl |
HN HN -It 0 I-H tO |
|
.2* ^B |
Ht n|co O l-H >^ |
|
Q cc |
fix -it 0 ^H l~ |
|
o cc |
«0hf «l* C5 O l^ |
|
0 M |
- x Hx -It Ci C5 tO |
|
d (M |
mlt HN t-- cj'irs |
|
d wit |
-IN l^ CO (M |
|
d HN |
ST^cT |
|
a -it |
«,x-|t«leo to t^ sc |
|
G |
HN «l» tS GO (M |
|
d Ntt |
HtHNWH" »n i^. i— i |
|
Diameter |
<JMP5 |
XHOHS
Hif
SOCKET BENDS.
< A
117
|th Bend.
118 GAS ENGINEER'S POCKET-BOOK.
Ordinary Stock Dimensions of Flanged Connections.
|
D |
In. H |
In. 2 |
In. 2^ |
In. a |
In. $i |
in. 4 |
4jf |
In. 5 |
In. 6 |
|
(1 |
2£ |
2| |
3i^ |
31 |
^ |
H |
5fi |
H |
6fl |
|
F |
71 |
81- |
9 |
10 |
10' |
12 |
|||
|
°4 |
|||||||||
|
H |
9 |
10 |
11 |
12 |
12* |
12i |
14 |
i«i |
18f |
|
II .... |
6 |
5J |
0 |
6| |
11 |
9| |
IOJ |
10 |
U« |
|
No. of Holes in Flange |
* |
4 |
4 |
4 |
4 |
4 |
4 |
4 |
6 |
|
Centres of Holes . . |
In. ^ |
In. M |
2 |
In. 6! |
In. 6* |
In. 7 |
In. 8 |
In. si |
In. 10 |
|
D . , ... |
In. 1* |
In. 2 |
In. 2^ |
In. 3 |
In. 8| |
In. 4 |
In. 4£ |
In. 5 |
In. 6 |
|
(1 . . . "'" '.A~. |
2£ |
9u |
8A |
3ii |
4 A |
4J |
S| |
nj |
m |
|
F .... |
G |
Qi |
7 |
T* |
»4L |
9 |
10 |
10i |
12 |
|
L . |
8| |
9§ |
J'f |
10| |
11 |
"A |
111 |
12^ |
12$ |
|
It .... |
1fi2 |
14f |
ISj |
HH |
1f>i |
IfU |
18J |
13i |
|
|
No. of Holes in Flange |
j |
4 |
4 |
4 |
^ |
4 |
4 |
4 |
6 |
|
Centres of Holes . . |
In. *| |
In. 4§ |
In. r>4 |
In. 5| |
In. 6* |
In. 7 |
In. 8 |
In. &i |
In. 10 |
|
D |
In. i| |
In. 2 |
In. 2i |
In. 3 |
In. BI |
In. 4 |
In. *i |
In. 5 |
In. G |
|
d |
2& |
2fl |
^ |
8* |
H |
4| |
B| |
g |
*H |
|
F .... |
6 |
8j |
7 |
n |
8i |
9 |
10 |
10| |
12 |
|
A |
i& |
7^ |
^ |
9& |
9& |
9& |
10 |
12& |
12i |
|
B |
7aa |
6| |
»i |
9* |
9i^ |
»* |
10 |
12i |
I2| |
|
No. of Holes in Flange |
4 |
4 |
4 |
4 |
4 |
4 |
4 |
4 |
|
|
Centres of Holes . . |
In. H |
In. *l |
In. 5i |
In. 5! |
In. 8J |
In. 7 |
In. 8 |
In. 8| |
In. 10 |
FLANGED CONNECTIONS.
119
|
~T |
— i «Q i |
|
|
!--^p- |
||
|
f A - — 4 — * — - — |
I JO
GAS ENGINEER'S POCKET-BOOK.
Diagram showing Weight of small Cast Iron Pipes of different Diameters and Thicknesses.
1 60
i'
3 4" 5" 6'' 7" 8" 9" 10'' n" 12'' Bore,
WEIGHT OF CAST IRON PIPES.
121
Diagram showing Weight of Cast Iron Pipes of different Diameters and Thicknesses.
20' 30
Diameters.
4°" 48"
122
GAS ENGINEER'S POCKET-BOOK.
Weight of Cast Iron Gas Pipes,
|
Internal Diameter. |
Thick- ness of Metal. |
1 Internal Diameter. |
Thick- ness of Metal. |
||||
|
Inches. |
Inches. |
Cwta. Qrs. Lbs. Inches. |
Inches. |
C\vts. Qrs. Lbs. |
|||
|
1 |
in |
0 1 3 |
(U |
& |
730 |
||
|
1| |
H |
A |
017 |
15 |
i |
8 1 0 |
|
|
^ bo |
2 |
£ |
0 1 16 |
16 |
i |
9 1 0 |
|
|
55 § |
21 |
i |
028 |
•j |
18 |
y |
11 1 0 |
|
3 |
_s_ |
0 3 18 |
-*-> 60 |
20 |
13 20 |
||
|
4 |
s |
1 1 13 |
i |
21 |
a |
14 0 0 |
|
|
XI |
5 |
1 3 8 |
— * * |
22 |
i |
15 0 0 |
|
|
f |
G |
i? |
2 1 15 |
i |
24 |
17 2 0 |
|
|
7 |
2 3 15 |
30 |
i |
2<5 1 0 |
|||
|
•£ |
8 |
12 |
3 1 24 |
OS |
36 |
i /,- |
34 3 0 |
|
1 |
9 |
r |
4 0 10 |
42 |
46 2 0 |
||
|
« 1 10 |
426 |
48 |
1A |
51 0 0 |
|||
|
112 |
i |
5 2 20 |
\ |
Proportions of Pipe Flanges. (Unwin.)
Thickness of flange = £ thickness of pipe (= 0 If joint is made with lead ring, thickness = % t Width of flange outside pipe = twice diameter of bolt + 1
/pressure in pipe Diameter of bolts = 0-016 diam. of pipe x V j • + 0-4
V Nn nf hnlrs
. of bolts
Number of bolts = 2
diameter of pipe 2
Diameter of bolt hole = diameter of bolt + $
Barffs process protects iron by forming on its surface a coating of magnetic or black oxide of iron, by subjecting the iron for some time to the action of superheated steam at a high temperature.
Dr. Angus Smith's process consists of heating the iron to 310° F. and plunging it in a bath of pitch maintained at a temperature of at least 210°. A little oil may be added to the pitch. Tar with a little tallow and resin forms a good coating to be applied cold.
The requisites of a good paint for the preservation of iron and steel are stated by Mr. Woodruff Jones to be these : (1) It should firmly adhere to the surface and not chip or peel off ; (2) It must not corrode the iron, otherwise the remedy may only aggravate the disease ; (3) It must form a surface hard enough to resist frictional influences, yet elastic enough to conform to the expansion and con- traction of the metal by heat and cold ; (4) It must be impervious to, and unaffected by, moisture and atmospheric and other influences to which it may be exposed.
LEAD PIPES.
123
A Coating for Cast Iron Pipes.
A bath made up of gas tar. Burgundy pitch, oil and resin, is kept at 400° F., and the pipes are laid 'in this until they are of the same heat as the bath, when they are set up on end to drain off.
Weight of Lead Pipe per Foot Kun.
|
Diameter. |
Light, i Middling, i Strong. |
Diameter |
Light. |
Middling. |
Strong |
||
|
Lbs. |
Lbs. |
Lbs. |
Lbs. |
Lbs. |
Lbs. |
||
|
^ in. pipe |
! |
1 |
H |
2£ in. pipe |
6 |
«j |
H| |
|
4 » |
1 |
11 |
2 |
2f „ „ |
— |
10 |
|
|
i |
11 |
2} |
3 |
^ » » |
10 |
12 |
13 |
|
2| |
3* |
4 |
•i "2 >5 5> |
H| |
13 |
15 |
|
|
H |
n |
4 |
54 |
1 „ ,, |
14 |
16 |
17 |
|
1* |
8 |
4 |
5 |
44 » « |
14 |
17 |
22 |
|
l* |
5 |
7 |
8 |
5 „ » |
15 |
22 |
25 |
|
2 |
5 |
G |
8 |
"•J !> » |
— |
22 |
|
|
n |
- 1 8* |
11 |
<> „ „ |
— |
22 |
A Table Showing the Weight of Lead Pipes per Length in Lbs.
|
Bore. |
Length. |
Common. |
Middling. |
Strong. |
|
Inches. |
Feet. |
Lbs. |
Lbs. |
Lbs. |
|
i |
15 |
16 |
||
|
3 |
15 |
24 |
27 |
30 |
|
1 |
15 |
30 |
40 |
43 |
|
H |
12 |
36 |
44 |
53 |
|
14 |
12 |
48 |
56 |
67 |
|
2 |
10 |
5(5 |
70 |
83 |
|
84 |
10 |
70 |
89 |
100 |
Weight of Composite Pipe per Yard.
inch inside diameter .
Lbs. Ozs. 0 13
0
5
10 2 4 4
12 8
124:
| inch inside diameter
13 » » J)
GAS ENGINEER'S POCKET-BOOK. Weight of Block Tin Tubes per Yard.
inch inside diameter
Lbs. Ozs. 0 8 0 i)i 0 11"
0 14
1 1
Weight of Copper Pipes.
Per foot.
2 inches diameter . . Hlbs. 1 4 inches diameter 2| „ ., . . If „
3 . 21 .
Lbs. Ozs. . 1 7 . 1 H
. 2 <;
. 2 15
Per foot. 3 Ibs.
**»
Soldering Tin.
Flux may be resin and sweet oil, spirits of salts (hydrochloric acid), killed with zinc cuttings, or Baker's mixture. Solder.— Two parts tin, 1 lead, melts at 340° F. Blow Pipe Solder. — 1£ parts tin, 1 lead.
Flux.— Dissolve zinc in hydrochloric acid until effervescence ceases ; filter the liquid, add | spirits of sal-ammoniac, and dilute with rain water.
Flux.— One part lactic acid, 1 part glycerine, 8 parts wrater.
These two fluxes will not rust iron or steel.
Weight of Black Sheet Iron and Rolled Brass.
|
Wire Gauge. |
Per Sheet, 72 x 24 in. |
Per Sheet, 72 x 30 in. |
Per Sheet, 72 x iJG in. |
P,T sq. foot. |
Sleet IJruss, per sq. foot. |
|
Nos. |
Qrs. Lbs. |
Qrs. Lbs. Qrs. Lbs. |
Lbs. |
Lbs. |
|
|
10 |
2 14 |
3 4 |
3 21 |
5| |
5 f |
|
11 |
2 4 |
2 19 |
3 6 |
5 |
5-L |
|
12 |
1 25 |
2 12 |
2 25 |
4-i |
4: |
|
13 |
1 20 |
2 4 |
2 16 |
4 |
4r |
|
14 |
1 13 |
1 23 |
2 5 |
3 a |
Bf |
|
15 |
1 8 |
1 17 |
1 21) |
3 |
si |
|
16 |
1 2 |
1 10 |
1 17 |
2£ |
2! |
|
17 |
0 27 |
1 6 |
1 13 |
2£ |
2J |
|
18 |
0 24 |
1 2 |
1 8 |
2 |
2J |
|
19 |
0 21 |
0 26 |
1 3 |
]} |
1* |
|
20 |
0 18 |
0 23 |
0 27 |
n |
M |
|
21 |
0 1(5 |
0 21 |
0 25 |
] i |
if |
|
22 |
0 15 |
0 19 |
0 23 |
i* |
i* |
|
23 |
0 14 |
0 17 |
0 20 |
i* |
i |
|
24 |
0 12 |
0 15 |
0 18 |
i |
15 oz. |
|
25 |
0 11 |
0 13 |
0 16 |
14 oz. |
14 oz. |
|
26 |
0 10 |
0 12 |
0 14 |
13 oz. |
12 oz. |
SCREW THREADS. Whitworth's Screw Threads.
125
|
Diar. |
Diar. at |
Area at |
No. of |
Width of |
Depth |
Diar. |
|
|
of |
bottom |
bottom |
Threads |
' Nuts across |
of Bolt |
of Bolt |
|
|
Screw. |
ofThread. |
of Thread. |
per In. |
Flats. |
Head. |
Head. |
|
|
Inches. |
Inches. |
Indies. |
Indies. |
Inches. |
Indies. |
Inches |
|
|
£ |
•0929 |
•006 |
40 |
•338 |
A-f JL F |
^L-f A |
\ |
|
3 1(1 |
•1341 |
•0141 |
24 |
•448 |
i-f gL B |
1 + JL |
|
|
•1859 |
•0271 |
20 |
•525 |
l + JL F |
A-f-gC |
! |
|
|
A |
•2413 |
•0457 |
18 |
•6014 |
^4-Jg F |
1 + JL |
|
|
| |
•2949 |
•0883 |
16 |
•7094 |
Ii + JL F |
A-f JL |
I |
|
•346 |
•0940 |
14 |
•8204 |
13-f _L B |
f F |
||
|
1° |
•3932 |
•1214 |
12 |
•9191 |
| + 5 B |
7 ^3 |
1 |
|
A |
•4557 |
•1626 |
12 |
1-011 |
1 + -1" B |
f |
|
|
? |
•5085 |
•2027 |
11 |
1-101 |
1|> v |
i |
|
|
•571 |
•2565 |
11 |
1-2011 |
l_?_-jl Jj B |
H |
||
|
3 |
•6219 |
•3037 |
10 |
1-3012 |
1 i -f JL F |
B+^ |
IA |
|
i |
•6844 |
•3687 |
10 |
139 |
H + £ B |
o 32 |
4° |
|
I |
•7327 |
•4026 |
9 |
1-4788 |
IJL -|_ji B |
f + ir |
|
|
y |
•7952 |
•4966 |
9 |
1-5745 |
!_»_ + j_ B |
ii F |
IJL |
|
i |
•8399 |
•5540 |
8 |
1-6701 |
1| -f A B |
^ |
I5 |
|
]i |
•942 |
•6969 |
7 |
1-8605 |
li^ + J^ F |
l! |
|
|
H |
1-067 |
•8941 |
7 |
2-0483 |
2^j F |
l|j |
|
|
1-1615 |
1-0592 |
6 |
2-2146 |
2A-f _L B |
1 -3- +"-1- |
2? |
|
|
4 |
1-2865 |
1-2999 |
6 |
2-4134 |
21| + JL F |
101^_6* |
2| |
|
1-3688 |
1-4715 |
5 |
2-5763 |
2-9- + 4^ B |
1 1 + — |
||
|
if |
1-49 |
1-7525 |
5 |
2-7578 |
2| F |
il+A |
2ii |
|
1-5904 |
1-9865 |
41 |
3-0183 |
3 J- F |
2X |
||
|
28 |
1-7154 |
2-311 |
4* |
3-1491 |
3i+AB |
4 |
3 A |
|
2J |
1-8404 |
2-6602 |
3-337 |
3i |
|||
|
2* |
1-9298 |
2-9249 |
±* |
3-546 |
31-f A B |
1— + -^ |
3f |
|
2| |
2-0548 |
3-3161 |
4 |
3-75 |
3J0i |
2-1- + -1- |
|
|
2-1798 |
3-7318 |
4 |
3-894 |
2A |
3f° |
||
|
2* |
2-3048 |
4-1721 |
4 |
4-049 |
4?& F |
2i + s3j |
3 » |
|
2| |
2-384 |
4-4637 |
3.1 |
4-181 |
4_s_B |
2| + ^5 |
4 |
|
2-509 |
4-9441 |
31 |
4-3456 |
4A + JL F |
2A + i |
4A |
|
|
38 |
2-634 |
5-4490 |
»* |
4-531 |
41 + JL B |
2| |
4° |
|
3^ |
2-884 |
6-5325 |
n |
||||
|
3i |
3-106 |
7-5769 |
3i |
||||
|
3| |
3-356 |
8-8457 |
3 |
||||
|
4 |
3-574 |
10-032 |
3 |
||||
|
•H |
3-824 |
11-481 |
2j |
||||
|
4.1 |
4-055 |
12-914 |
2I |
||||
|
4| |
4-305 |
14-556 |
2| |
||||
|
5 |
4-534 |
16-145 |
2| |
||||
|
B* |
4-764 |
17-826 |
2| |
||||
|
5-014 |
19-745 |
2f |
|||||
|
M |
5-238 |
21-548 |
2i |
||||
|
6 |
5-488 |
23-654 |
2i |
126 GAS ENGINEER'S POCKET-BOOK.
Wrought Iron Bolts (Whitworth Thread).
|
Diar. of Screw. |
Safe Working Load, allowing a Stress 4,000 to 10,000 Ibs. • |
||||||
|
Inches. |
4,000. |
5,000. |
0,000. |
7,000. |
8,000. |
9,000. |
10,000. |
|
§ |
26 |
33 |
.. 40 |
46 |
53 |
60 |
67 |
|
IS |
56 |
70 |
84 |
98 |
112 |
126 |
141 |
|
108 |
135 |
162 |
189 |
216 |
243 |
271 |
|
|
& |
182 |
228 |
279 |
319 |
365 |
411 |
457 |
|
253 |
347 |
409 |
478 |
546 |
614 |
683 |
|
|
)o |
376 |
470 |
564 |
658 |
752 |
846 |
940 |
|
i |
485 |
607 |
728 |
849 |
971 |
1,092 |
1,214 |
|
IB |
650 |
813 |
975 |
1,138 |
1,300 |
1,463 |
1.626 |
|
* |
818 |
1,013 |
1.216 |
1,418 |
1.621 |
1,824 |
2,027 |
|
y |
1,026 |
1.282 |
1.539 |
1,795 |
2.052 |
2,308 |
2,56.") |
|
1,214 |
1,518 |
L822 |
2,125 |
2,429 |
2,733 |
3.037 |
|
|
y |
1.474 |
1.843 |
2,212 |
2.580 |
2,949 |
3,318 |
3.687 |
|
i |
1,660 |
2.013 |
2.415 |
2,818 |
3,220 |
3,623 |
4^026 |
|
y |
1,986 |
2,483 |
2,979 |
3,476 |
3,972 |
4,469 |
4.966 |
|
i |
2,216 |
2,770 |
3.324 |
3.878 |
4^432 |
4,986 |
5,540 |
|
H |
2,787 |
3,484 |
4,181 |
4^78 |
5;575 |
6.271 |
6,969 |
|
U |
3,576 |
4,470 |
5,364 |
6.258 |
7^152 |
8,046 |
8,941 |
|
if |
4,236 |
5^296 |
6,355 |
7.414 |
8,473 |
9,532 |
10.592 |
|
H |
5,199 |
6,499 |
7,799 |
9,05)9 |
10.399 |
11,699 |
1 2,999 |
|
if |
5.886 |
7,357 |
8,829 |
10.300 |
11,772 |
13^243 |
14,715 |
|
1* |
7,010 |
8.762 |
10,515 |
12.267 |
14.020 |
15,772 |
17,525 |
|
*I |
7^946 |
9,932 |
11.919 |
1 3,905 |
15.892 |
17.878 |
19.865 |
|
2 |
9,244 |
1 1 ,555 |
13.866 |
16,177 |
18.488 |
20,799 |
23,110 |
|
2J |
10,640 |
13.301 |
15,961 |
18,621 |
21,281 |
23.941 |
26,602 |
|
2i |
11,699 |
14.624 |
17,549 |
20,474 |
23,399 |
26,234 |
29.249 |
|
2i |
13,264 |
16,580 |
19,896 |
23.212 |
26,528 |
29^844 |
33,161 |
|
2| |
14,927 |
18,659 |
22,390 |
26,122 |
29,854 |
33,586 |
37.318 |
|
2f |
16,688 |
20,860 |
25,032 |
29,204 |
33,376 |
37,548 |
41.721 |
|
2f |
17,854 |
22^318 |
26,782 |
31,245 |
35,709 |
40,173 |
44^637 |
|
2| |
19,776 |
24,720 |
29,664 |
34.608 |
39,552 |
44,496 |
49,441 |
|
3 |
21,796 |
27,245 |
32,694 |
38,143 |
43,592 |
49,041 |
54.490 |
|
3i |
26.130 |
32.662 |
39.195 |
45,727 |
52^260 |
58,792 |
65,325 |
|
3| |
30,307 |
37,884 |
45,461 |
53,038 |
60^615 |
68,192 |
75.769 |
|
3f |
35,382 |
44,228 |
53,074 |
61.918 |
70,765 |
79,611 |
88,457 |
|
4 |
40,128 |
50,160 |
60,193 |
70,224 |
80,256 |
90,288 |
100,320 |
|
H |
45,924 |
57,405 |
68,886 |
80,367 |
91,848 |
103,329 |
114,810 |
|
H |
51,656 |
64,570 |
77,484 |
90,398 |
103,312 |
116,226 |
129,140 |
|
4J |
58,224 |
72,780 |
87,336 |
101,892 |
116.448 |
131,004 |
145,560 |
|
5 |
64,580 |
80,725 |
96,870 |
113,015 |
123,160 |
145,305 |
161,450 |
|
&| |
71,304 |
89,130 |
106,956 |
124,782 |
142,608 |
160,434 |
178,260 |
|
5i |
78,980 |
98,725 |
118.470 |
138,215 |
157,960 |
177,705 |
197,450 |
|
5$ |
86,192 |
107,740 |
129,288 |
150,836 |
172,384 |
193,932 |
215,480 |
|
6 |
94,616 |
118,270 |
141,924 |
165,578 |
189,232 |
212,886 |
236,540 |
SCREW THREADS.
Whit worth's Standard Screw Threads.
127
|
Outside Diameter in Inches. |
Diameter at bottom of Thread. |
Nearest Size for Drilling |
Number of Threads per Inch. |
Outside Diameter in Inches. |
Diameter at bottom of Thread. |
Nearest Size for Drilling |
Number of Threads per Inch. |
|
1 |
•093 |
n H |
40 |
16 |
•455 |
y |
12 |
|
I |
•112 |
ft |
32 |
i 8 |
•508 |
33 05 |
11 |
|
• id |
•134 |
9 (H |
24 |
y |
•571 |
8 |
11 |
|
S2 |
•165 |
tt |
24 |
i |
•622 |
i 8 |
10 |
|
•186 |
V is |
20 |
a |
•684 |
y |
10 |
|
|
5 1(1 |
•241 |
18 |
•732 |
17 til |
9 |
||
|
§ |
•295 |
H |
16 |
y |
•795 |
8 |
9 |
|
7 • |
•346 |
i |
14 |
i |
•841 |
i |
8 |
|
4 |
•393 |
i |
12 |
Hoop Iron.
|
B. W. Gauge. |
Width in Inches. |
Weight per Foot Run. |
Weight per 100 Foot Run. |
B. W. Gauge. |
Width in Inches. |
Weight per Foot Run. |
Weight per 100 Foot Run. |
|
Lbs. |
Lbs. |
Lbs. |
Lbs. |
||||
|
12 |
21 |
•91 |
91-78 |
16 |
H |
•27 |
26-52 |
|
13 |
H |
•71 |
71-23 |
17 |
H |
•21 |
20-84 |
|
13 |
2 |
•63 |
63-31 |
IS |
i |
•16 |
16-16 |
|
14 |
n |
•48 |
47-15 |
19 |
i |
•12 |
12-37 |
|
15 |
H |
•36 |
36-37 |
20 |
' 2 |
•087 |
8-84 |
|
15 |
If |
•33 |
33-34 |
Rust Joint Cement for Cast Iron Tanks and Cisterns.
Cast iron borings . . . 5 Ibs. Powdered sal-ammoniac . 1 oz. Flour of sulphur . . 2 ozs.
mix with
Another and perhaps better cement is —
Cast iron borings . . . 6 Ibs. j Powdered sal-ammoniac . 1 oz. /• mix wl Flour of sulphur . . . ^ oz )
?Z&
^> OF THE
UNIYERS
•oP1
128
GAS ENGINEER'S POCKET-BOOK.
Working Safe Stresses in Its. per Square Inch.
|
Tension. |
Compression. |
(Shearing. |
|
|
Cast iron . . . |
3,000 |
10,400 |
2,700 |
|
Wrought iron bars . . |
10,400 |
10,400 |
7.800 |
|
„ „ plates |
10,000 |
10,000 |
7,800 |
|
Soft steel, untempered . |
17,700 |
17,700 |
13,000 |
|
Cast ., |
52.000 |
52,000 |
38,500 |
|
Copper |
3,600 |
3,120 |
2,300 |
|
Brass . . . . |
8,600 |
— |
2.700 |
|
Gun metal . |
3,120 |
— |
2.400 |
|
Phosphor bronze . |
9,870 |
— |
7,380 |
Comparative Weights.
|
Cast Iron. |
Bar Iron. |
Steel. |
Brass. |
Copper. |
Gun Metal. |
Lead. |
Yellow Pine. |
|
|
Cast iron = | 1 |
•953 |
•925 |
•807 |
•83 |
•8288 |
•04 |
10-0 |
|
|
Bar iron = 1.048 |
1 |
•973 |
•909 |
•8(50 |
•8087 |
•07 |
16-8 |
|
|
Steel = |
1-07(1 |
1-026 |
1 |
•933 |
•89 |
•8917 |
•088 |
17-0 |
|
Brass = |
1-153 |
1*1 |
1-07 |
1 |
•95 |
•9558 |
•737 |
18-8 |
|
Copper = |
1-213 |
1-151 |
1-123 |
1-05 |
1 |
1-0004 |
•774 |
19-3 |
|
Gun metal = |
1-208 |
1-150 |
1-121 |
1-040 |
•99 |
1 |
•773 |
19-0 |
|
Lead = |
1-5(54 |
1-5 |
1-453 |
1-357 |
1-29 |
1-292 |
1 |
24-0 |
|
Yellow pi ne= |
— |
— |
~— |
— |
— |
— |
— |
1 |
Weight of a Foot Superficial of Parts of an Inch in Thickness.
|
& |
i |
i |
I |
i |
i |
t |
I Im-h. |
|
|
Steel . ', |
2-05 |
5-1 |
10-2 |
15-3 |
20-4 |
25-5 |
30-0 |
35-7 40-8 |
|
W.iron . |
2-50 |
5-00 |
10-00- |
15-00 |
20-00 |
25-00 |
30-00 |
35-00 40-00 |
|
C. iron |
2-35 |
4-09 |
9-37 |
14-00 |
18-75 |
23-44 |
23-12 |
32-81 37-50 |
|
Brass . . |
2-84 |
5-08 |
11-35 |
17-03 |
22-70 |
28-38 34-05 |
39-72 45-40 |
|
|
Copper . |
2-89 |
5-78 |
11-50 |
17-34 |
23-12 |
28-90 |
34-08 |
40-40 40-24 |
|
Lead, cast |
3-70 |
7-39 |
14-78 |
22-17 |
29-50 |
30-95 |
44-34 |
51-73 59-12 |
WEIGHT OF DIFFERENT METALS. 129
Weight per Square Foot of Various Thicknesses of Different Metals,
Lead.
Copper. Brass.
Steel. Wrotlron
Cast Iron and Zinc.
A ft A 1 A * rf« i A I H I it I H
Thickness of Metal.
G.E.
130 GAS ENGINEER'S POCKET-BOOK.
Handy rule for weight of Wrought Iron Plate :—
1 superficial foot of £ inch plate weighs about 10 Ibs.
Round Rods, To find breaking weight of, square of diameter in J inches *= B. W,
diameter^ in } inches
_ wdght ^ ^ per yard>
Kesistanoe to shearing of wrought iron bars, ultimate = 18 to 20 tons per square inch.
Weight of Half-round Iron and Steel Bars.
|
Breadth in Inches. |
Thickness in Inches. |
Sectional Area, Square Inches. |
Weight per Lineal Foot. |
|
|
Iron. |
Steel. |
|||
|
1| |
10 |
0-249 |
0-83 |
0-85 |
|
H |
A |
0-273 |
0-91 |
0-93 |
|
!i |
0-864 |
1-21 |
1-24 |
|
|
i |
0-395 |
1-32 |
1-34 |
|
|
If |
0-451 |
1-50 |
1-53 |
|
|
2 |
3 |
0-514 |
1-71 |
1-75 |
|
21 |
^ |
0-859 |
2-86 |
2-92 |
|
2$ |
1 |
1-097 |
8-66 |
8-73 |
Weight of Sheet Brass in Ibs. per Square Foot.
|
Thickness. |
Weight |
Thickness. |
Weight |
Thickness. |
Weight |
|||
|
liirin. |
in |
Birm. |
in |
Birm. |
in |
|||
|
Wire |
Inches. |
Ibs. |
Wire |
Inches. |
Ibs. |
Wire |
Inches. |
Ibs. |
|
Gauge. |
Gauge. |
Gauge. |
||||||
|
No. 3 |
0-259 |
10-9 |
No. 11 |
0-120 |
5-05 |
No. 19 |
0-042 |
1-77 |
|
» 4 |
0-238 |
10-0 |
„ 12 |
0-109 |
4-59 |
„ 20 |
0-035 |
1-47 |
|
5 |
0-220 |
9-26 |
„ 13 |
0-095 |
4-00 |
„ 21 |
0-032 |
1-35 |
|
6 |
0-203 |
8-55 |
» 1* |
0-083 |
3-49 |
„ 22 |
0-028 |
1-18 |
|
7 |
0-180 |
7-58 |
„ -16 |
0-072 |
3-03 |
.„ 23 |
0-025 |
1-05 |
|
8 |
0-165 |
6-96 |
„ 16 |
0-065 |
2-74 |
» 24 |
0-022 |
0-926 |
|
9 |
0-148 |
6-23 |
» I7 |
0-058 |
2-44 |
„ 25 |
0-020 |
0-842 |
|
10 |
0-134 |
5-64 |
,,18 |
0-049 |
2-06 |
» 26 |
0-018 |
0-758 |
Comparative Strengths of Steel, Wrought Iron, and Cast Iron. Relative areas required to withstand a given strain.
Tension. Torsion. Compression.
Steel .... 2-23 3-33 1'43
Wrought iron . . . 4-44 5-00 5-23
Cast iron . . . 9-45 36-00 2-45
The cohesive power of iron and cement equals 40 to 47 kilometres per square centimetre.
Iron embedded in cement does not rust.
THICKNESS OF WROUGHT IRON PIPES.
131
Strength of Double-Headed Kails (Steel),
Breaking weight at centre = 30 (ia -- +
a = area of one flange in inches.
d = depth over all of rail in inches.
d" =* vertical distance apart of centres of
t = thickness of web.
L = length of span in inches,
Table of Wrought Iron Pipe Thicknesses,
|
To Stand |
|||||||
|
700 Ibs. |
|||||||
|
Hydraulic Piping- |
|||||||
|
Gas and Water Piping. |
Wrought Iron. |
Hydraulic |
|||||
|
Piping- |
|||||||
|
Cast Iron. |
|||||||
|
Number of |
Internal |
Number |
|||||
|
Internal Diameter of Pipe. |
External Diameter of Pipe. |
Threads per Inch. Whit- worth |
Diameter to stand 4,000 Ibs. aer Square |
External Diameter of Pipe. |
of Threads aerlnch. Whit- |
Internal Dia- meter of Pipe. |
Thick- ness of Pipe! |
|
Threads. |
Inch. |
worth Threads. |
|||||
|
Inches. |
Inches. |
Inches. |
Inches. |
Inches. |
Inches. |
||
|
i |
0-656 |
19 |
i |
t |
14 |
H |
30 |
|
i |
0-825 |
14 |
1 |
14 |
If |
||
|
t |
1-041 |
14 |
§ |
H |
14 |
2 |
1 |
|
i |
1-309 |
11 |
I |
H |
11 |
4 |
1 |
|
il |
1-492 |
11 |
it |
31 |
2| |
||
|
H |
1-650 |
11 |
i |
H |
11 |
3 |
i |
|
ij |
1-745 |
11 |
H |
if |
11 |
31 |
|
|
H |
1-882 |
11 |
H |
i- |
11 |
4 |
" 3. |
|
2-021 |
11 |
]i |
11 |
5 |
1 |
||
|
i| |
2-158 |
11 |
H |
28 |
11 |
.6 |
I |
|
v |
2-245 |
11 |
i§ |
2i |
11 |
||
|
2 |
2-347 |
11 |
if |
2* |
11 |
||
|
24 |
2-467 |
11 |
M |
2| |
11 |
||
|
2* |
2-587 |
11 |
2 |
8 |
11 |
||
|
2i |
2-794 |
11 |
|||||
|
3-001 |
11 |
132 GAS ENGINEER'S POCKET-BOOK.
NOTES ON WROUGHT IKON GIRDERS.
Depth.— The depth of girders in ordinary cases should be from tk to ^ of span, if intended to serve as a parapet may be increased to &, in flooring £.
Weight.— The weight in tons may be found approximately by multiplying the load to be carried by the total length of girder and dividing by 400.
Strain.— The safe strain when not given may be assumed at 5 tons in tension or 4 tons in compression per square inch.
Bearing Surface. — The bearing surface in square feet may be found by dividing the weight on abutment by one of the following constants according to the material of abutment, viz. : — Granite 25, limestone 25, sandstone 15, firebrick 10, strong red brick 7, weak red brick 3J.
Camber. — Half an inch rise per 10 feet length of girder.
Area of Flanges.— Section of top or bottom flange to girder at intermediate points from centre.
1. Distributed load.
Jj
w * 2 = Section area of top or bottom flange in centre in square inches.
2. d = distance of point from nearest support.
•ytr ., ,7
= Sectional area of flange at any other point in square
inches. 3. x — Sectional area at any point.
x x D .x 4 x . _ Distance Of gucjj section from nearest support.
Example. — A girder 20 feet long carries a distributed load of 40 tons, and is»2 feet deep,
By (1) 40 x 10 = 10 inches sectional area. 2x4x5
By (2) Sectional area required 3 feet from end.
40 x 3
= 3 inches sectional area.
2x4x5
By (3) Suppose flange to be made of 3 plates, each 3*3 inches area, centre section will be 10 inches ; section outside first plate will be 6'6 inches ; section outside second plate will be 3 '3 inches.
10 x 2 x 4 x 5 _ 1Q feet distance of section of 10 inches from support.
6-6x2x4x5 _6 feet 6 incheg distance Of section of 2 plates from end = (20 feet - 13 feet 2 inches) = length of plate 6 feet 6 inches.
WROUGHT IRON GIRDERS. 133
8-3 x 2 x 4 x 5 _ 3 feet 3 .ncheg distance of section of 1 plate from end = (20 feet - 6 feet 6 inches) = 13 feet 2 inches length of second plate.
k~~ -I- - 2o!o; .... 4
fc 13:21 J
jr e.'e "~H{ ^
Section3-$" Section 6 6 Section 10'
Tn rolled joists ith of the area of web may be included in each of the areas of the top and bottom flanges when calculating the strength of the joist.
To find the net area of a joist in inches —
A __ W I; _ f JL. 5 = inches area if wrought iron. : sd s asj-7= „ „ „ steel.
To find W = distributed load—- — jj
„ „ d = depth of girder in feet — Q •
L x W
5> >'
a, = net section in inches —
C x D
A x d x c „ „ L = span— — rrr
L x W
„ „ S = tons strain per square inch — o ~r — •>
134
GAS ENGINEER'S POCKET-BOOK.
r- O o O «w
e3 ^ ^ 5
&, -^
d ®
O J3
d o .3 o .S £ rf ^
a"! To 1 5- 12
H"*"-" ifl > "^ r! «J SH _i
S. 5^
dr« pj
o
ill ill
5'C
S $
1 1
^ 03 a 3
IIP i|f||i
fill ^il^-s^
CC f> p~~l f> j O rH ^
llli Ifl^
l^il
a S^ «
"^o - 'd -d
° o d
-t-1 "*"* ^J
•fib
~~ c ^3 -S »a >rt
IJg^lgl5.a
^ssa&s'g-"
0^.2^ S1^ § 2
S I II
«
a s
•J.33J Nl NVdS
S
;
o o < O
I
I-
STRENGTH OF ROLLED JOISTS.
135
Diagram to find the Proper Size of Rolled Iron Joist.
For any given Distributed Load. (Factor of Safety, |rd)— continued.
IS.?'
2 & 456 78 8 10
V* SAFE LOAD IN
136
GAS ENGINEER'S POCKET-BOOK.
Moments of Inertia and Resistance of Beams, Solid Rectangle.
BD3 ad*
T
12
Hollow Rectangle. *— B
Solid Circle.
R = CBD2 = Cad - M 6 6
- I'd'*
R =
Hollow Circle.
Solid Elliptical Section.
I = -7854 BD3 R = -7851 CBD2 = M
~2^~-
MOMENTS OP INERTIA.
Hollow Elliptical Section.
I = -7854 (BD3 - B'D'r/
R = '7854 C (BD« - B'P'») _ M
131
One Flange.
I = i BD3 + B'D'3 - (B' - B) D"s
= M
- (B - K) (D- C)3 + BD'3 - (B' - K) (D' - C');
Wooden Joists (square or rectangular)—
Bx dl x °'2 # fir or pine ) _ Breaking weight in tons on centre.
Cast iron beams— 2d x area of bottom flange in inches _ ^ ^ Area of top flange should equal one-third that of bottom flange,
138 GAS ENGINEER'S POCKET-BOOK.
Wrought iron beams with top and bottom flange — 6d x area of bottom flange in inches -f- ftth area of web _ L
B and d in inches, L in feet. Rivet holes deducted when calcu- lating area of web and flange. Box girders are about 8 per cent, stronger than single plate girders.
Relative Strength of Beams or Girders.
Relative .Strength.
Supported at one end and loaded at the other = 1
,, „ „ „ load distributed = 2
„ „ both ends „ „ at centre = 4
•„ „ „ „ „ distributed = 8
Firmly fixed at both ends and „ „ = 16
Bule for Distributed Breaking Weight on Steel Joists. 8 x D x strain on bottom flange
L
D = depth. L = length.
Strain = area of bottom flange + £th area of web x 28 tons per inch.
Board of Trade Regulations for Bridges.
Greatest stress per square inch in any part not to exceed 5 tons either in tension or compression when made in wrought iron.
When of cast iron the factors for dead load are taken and that portion of the load which is moving is doubled.
When of steel the greatest stress per square inch not to exceed 6 1 tons.
Fonts et Chaussees allow 3-81 tons per square inch in wrought iron girders in compression or tension.
Cast Iron Girders. If supported at both ends and centre load W =
T ., „ distributed load W = *—
Ju
With distributed load, if d = & L, W = A 4-17 „ = i L, W = A 5
£. If load is placed on top flange, area should = —
O
A
If load is placed on bottom flange, area of top flange should =-^
2d
Depth at ends should = — - o
CAST IRON GIRDERS.
139
With a test load = £ W, safe deflection equals JL inch per foot of span In the above W = breaking weight in tons.
a = area of bottom flange in inches.
d = depth of girder in inches over both flanges.
L = span of girder in inches.
If the depth of a wrought iron plate girder equals g- , then strain on top or bottom flange at centre in tons equals distributed load.
If the depth of a wrought iron plate girder equals — , then strain on top or bottom flange at centre in tons equals 1£ distributed load.
If the depth of a wrought iron plate girder equals -7, then strain on top or bottom flange at centre in tons equals 1| distributed load.
Continuous Girders.
The distance of the point of contrary flexure from pier, when the load on each span is equal, is ^ span. When the load is greater on one span than the other the distance equals
(7 load on first span - load on the other \ x span I 8 load on first span /
The pressure on the abutments
(7 load on. first span - load on the other E .
The pressure on centre pier equals f span (load on first span -f load on the other).
Thickness of Web Plates Required to Resist Diagonal Forces. (Chas. Light.)
|
Thickness |
Net Unsupported Distance in Inches, whether between Pillars or Booms. |
|||||||||
|
of Web. |
||||||||||
|
24 |
27 |
30 |
33 |
36 |
39 |
42 |
45 |
48 |
51 |
|
|
Inches. |
||||||||||
|
i |
1-5 |
1-2 |
1-0 |
•8 |
•7 |
•6 |
•5 |
•45 |
•4 |
•36 |
|
TV |
2'8 |
2'2 |
1-8 |
1-5 |
1-3 |
1-2 |
1-0 |
•9 |
•8 |
•7 |
|
| |
4-3 |
3'5 |
3-0 |
2'6 |
2'2 |
1-9 |
1-7 |
1-5 |
1-3 |
1-2 |
|
TV |
6-3 |
5'3 |
4'5 |
3-9 |
3'4 |
2-9 |
2-6 |
2:3 |
2-0 |
1'8 |
|
i |
8-7 |
7'4 |
6'3 |
5-5 |
4'8 |
4'2 |
3-7 |
3'3 |
3-0 |
2-7 |
|
11-2 |
9-8 |
8-5 |
7-4 |
6-5 |
5'7 |
5-1 |
4'6 |
4-2 |
3'8 |
|
|
A. |
14-0 |
12-3 |
10-8 |
9-5 |
8'4 |
7-5 |
6-7 |
6-0 |
5'4 |
4-9 |
|
ii |
17-0 |
15-0 |
13-4 |
11-9 |
10-6 |
9-5 |
8'5 |
7-6 |
6'8 |
6-3 |
|
1 • |
20-0 |
17-9 |
10-1 |
14-5 |
13-0 |
11-7 |
10-5 |
9-5 |
8'6 |
7'8 |
Tabular numbers show safe thrust in tons per foot width of plate. Tabular numbers under distance required must not be less than the shearing force per foot of plate.
140
GAS ENGINEER'S POCKET-BOOK.
Limits of Weights. &c., of Wrought Iron that can be used without Increase of Cost.
|
Length. |
Width. |
Area. |
Weight. |
Depth. |
|
|
Plates . . Bar Iron . L & T bars . Channel or E.J. . . |
15 ft, 30 to 35 ft. 35 ft, 35 ft. |
4 ft. flat bars, Gin. breadth and depth added 8i . . . . |
28 sq. ft. |
4 cwt. ; 1 5, |
7 ins. |
Transverse Strength of Plates. (Deduced from Rankine.)
Plate supported at 2 sides, distributed load, strength — L
IQlibd* Square „ 4 „ ,, „ „ = j-—
4 ., central „ „ =-"17
Circular, supported all round, distributed load, strength 3-1416 X 8Md*
Circular, supported all round, central load, strength 9-42 X
If firmly riveted to an immovable abutment, strength equals 1*5 above strengths.
Formula to obtain Ultimate Strength of Angle, or Tee Iron or Steel Struts (as for struts in roof trusses).
Breaking load in Ibs. per square inch of area of cross-section of pillar =
Coefficient length in inches3
least radius of gyration2 x EC
Coefficient for wronghtiron equals 40,000. K = if both ends flat or fixed, 36,000 to 40,000.
Coefficient for cast iroa equals 80,000. K = if both ends hinged, 18,000 to 20,000.
Coefficient for soft steel equals 52}000. K = if one end flat or fixed, other hinged, 24;OQO to 305OQ0«
LEAST RADIUS OF GYRATION. 141
Least Badius of Gyration, (Adapted from " Trautwine.")
Equal Angles.
1 x 1 x £ = -20 1 xl x £ = -20 IJxlJx £ = '26
ltxlixf=*6
2 x2 xA = -40 2 x2 x $ = '38
4x2|x| = -44 2^x2^x £ = '50 2ix2£x £ = -49
2|x2f 2f x2f 3 x3 3 x3
4x4x 4x4x 5 x 5 x jj 5x5x1 6x6x fg = l'19 6x6x1 =1-17
= -81 = -80 1 = 1-00
= "98
Unequal Angles.
3 x2 x 3 x2 x 3 x 21 x 3 x2|x 3i x 2i x 3£ x 2^ x 3^x3 x 3£ x 3 x
r='46
^•54 ,= •56
x3 x x3 x
= -67
= -73
4^x3 x | = '68 5 x3 x f = '70 5 x 3 x I = '69
5 xBi
5 x3J
5 x4'
5 x4
x | = -80
x f = -87 xl =-86
6 x3^xl ='81
6 x4 x ^= -92
6 x4 xl =-91
6J x 4 x ^ = '94
6^x4 xl =-93
7 x3£xl =84
Equal Tees.
Unequal Tees.
1 x 1 x A = -26
If xlf x i^-37 2 x2 x4 = -43
3 x3 x ^ = -62
42X4xix | = -84
2 xl x j = -26
2 xl.i x £ = -43 2£xl|x i^-33
3 x3|x | = -61
4 x2 x i=-58
4 x3 4 x3J
7\ V V
O X £~*
5 x3i
5 x4
•86 •88 •91 •72 •70
Roughly, weight of wrought iron bridge may be assumed — For 30 feet spans, single line, 5 cwt. per foot run
60 100 150
200
» » V A' 11 »
Dense crowds average 120 Ibs. per square foot. For flooring, 1£ cwt. to 2 cwt. per square foot, exclusive of weight of flooring.
142
GAS ENGINEERS POCKET-BOOK.
In storehouses, from 2 cwt. to 4 cwt. per square foot. Under no circumstances is a girder of less than ^th of the span advisable.
Bolt Centres in Angle Irons.
A. 1* If 2
f
B. }
1*
If U
c.
n i-i
B.
?
c.
If
if if
2
x area of web below centre of gravity L
Boiled T Iron
breaking weight.
A distributed load causes stresses only one-half as great as a centre load.
A load at end of a projecting beam or cantilever causes stresses, four times as great as a centre load.
Size of L Iron Laths for Slate Roofs.
|
Distance Apart of Principals. |
Laths 12 Inches Apart. |
Laths 10£ Inches Apart. |
Laths Si Inches Apart. |
|
5 0 5 6 |
1" X 1" X 8 W. g. |
If X If X 9w.g. |
i If X If |
|
6 0 6 6 |
If x If x G w. g. |
If x If x 8w. g. |
j x 9 w. g. |
|
7 0 |
If x If x f |
If x If x Gw.g. |
If x If x 8w.g. |
Tie Eods should have end eyes of the following proportions,
Proportions of Plate, Flanges, and Bolts. (Unwin.)
Bolt diameter = d = |ths thickness of plate + Jth (but not less than f inch).
ARCHES. H3
Pitch of bolts about 6<7, or less if necessary for strength. Width of chipping strip equals f thickness of plate. Width of flange equals 2d + f.
Approximate rule for depth of arches :—
C ^/~r = D C = coefficient = for stone '3, brick '4. rubble -45. r = radius of curve.
Minimum thickness of abutments for arches of 120 degrees where the depth does not exceed 3 feet
r equals radius ; h equals height of abutment to spring ; t equals thickness of abutment.
The abutments are assumed to be without counterforts or wing walls.
Strength of Flat Plates, (Grashof.) If supported on a circular support and uniformly loaded —
Greatest stress = g radius °* support* x w< e
. thicimess of plate2
If cncastre at the edge — •
Greatest stress = jj — x W. per square inch.
J thickness2
If supported only and with central load —
/ 4 r \ P
Greatest stress = ( .7 log- — + 1 j — \ 6 ro ) '
- = 10 << )' 4
— = 10 20 30 40 50
r * log.-— + 1 = 4-07 5-00 5-53 5'92 6'22
Modulus of Elasticity.
Wrought iron 29.000,000
Steel 30,000,000
Cast iron 17,000,000
Wood, hard . ... 1,500,000
„ soft 1,400,000
GAS ENGINEER'S POCKET-BOOK.
Moments of Inertia,
Circular section (diameter = d"), 0-0491 d*
Annular section (diameters = dlt f/2), 0-0491 (^x 4-^a 4)
Square section (length of side = *<?)» iV*
Rectangular section (longer side J, shorter 1i), ^ bh3
Cross-shaped section, if bending, is parallel to H, ^ (JH3 — 1
Cupolas for Melting Iron,— Average Sizes.
|
Diameter of Shell. |
Quantity of Metal Melted per hour. |
Height about. |
Diameter of Shell. |
Quantity of Metal Melted per hour. |
Height about. |
|
Ft. Ins. |
Ft. Ins. |
Ft. Ins. |
Ft. Ins. |
||
|
1 10 |
10 cwt. |
12 10 |
3 9 |
3i tons |
20 9 |
|
2 0 |
15 „ |
13 6 |
4 0 |
4 „ |
22 0 |
|
2 6 |
1 ton |
15 0 |
4 6 |
5 |
25 0 |
|
2 9 |
H „ |
16 3 |
4 9 |
H |
26 0 |
|
3 0 |
2 „ |
17 6 |
5 0 |
6 |
28 0 |
|
3 6 |
3 „ |
20 0 |
Water will ooze through cast iron -| inch thick at 250 Ibs. per square inch.
Water is only compressible nnnith Part ty a pressure of 324 Ibs. per square inch, or 22 atmospheres, and regains its bulk on removal of the pressure.
STACKING COALS.
145
UNLOADING MATERIAL AND STOEAGE
21 bushels coke = 1 cubic yard.
72 55 j, = 1 ton.
To measure a heap of coals, from 40 to 43 cubic feet should be taken for each ton.
Cannel coal, 45 cubic feet per ton.
Mr. Wyatt says 2£ acres are required per 1,000,000 cubic feet per day.
Coal store should equal 6 weeks' supply.
Coal storage, Newbigging's rule, 6 to 8 weeks' maximum make.
Space Occupied per Ton of Different Coals.
|
Welsh anthracite „ bituminous Lancashire Newcastle Scotch |
= 39 cubi = 43 . = 44 = 43 ', |
c feet ?? ;j >j |
Weight per Cubic Foot. 58-25 Ibs. 53 „ 53 „ 50 „ 53 „ |
Navy allowance for storage = 48 . .,
Coke in bays measures per chaldron 52 to 52^ cubic feet per chaldron.
Coke diminishes in weight by exposure to the weather. (See also p. 232.)
Average Weight of Various Coals.
|
Per Cub. Ft. Solid. |
Per Cub. Ft Heaped. |
Cub. Ft. per Ton. Heaped. |
Per Cub. Yd. Solid. |
|
|
Anthracite Bituminous . Cannel Coal as stored |
85-4 Ibs. 78-3 „ 76-8 „ |
58-3 Ibs. 49-8 „ 48-3 „ |
38-4 c. ft. 45-3 „ 46-4 „ |
2,160 Ibs. 2,100 „ 2,190 „ 1,150 „ |
Coal Stores.
Coal stores in the open should be paved with a slope to carry off rain water.
Ventilation of coal stacks may be effected by constructing open piers of brickwork or wood, or inserting perforated pipes, round which the coal is laid ; or wicker tubes.
G.E. L
146 GAS ENGINEER'S POCKET-BOOK.
In designing walls for coal stores the object to be attained is to keep the centre of gravity of the mass of the wall as much towards the inner side as possible, as the strength of a wall to resist side pressures varies as the distance from the centre of gravity to the outside edge of the wall at the base, and as the weight on the foundations. On this account walls with panels sunk in are usually adopted.
There can be little or no assistance from cross walls inside coal stores, or from the end walls, more especially when the walls are thick, a necessity where much coal has to be stored. The corners of such buildings frequently develop cracks from top to bottom of the walls nearly vertical, which would entirely remove any advantage which the side walls might have otherwise given. Probably the cause of these cracks is the expansion taking place in long walls exposed to the sun while the end walls are cool and shaded.
Iron ties are not reliable when imbedded in the coals, as when the latter heat the ties extend, and the tension on the walls is relaxed ; and this may cause the wall to overturn through the upsetting of the centre of gravity of the wall.
Mr. F. Marshall has designed a coal store with the floor a series of inverted pyramids, the sides of which are built of " Monier " concrete arches, the bottom points of the pyramids being so arranged that the coal may pass out in a regulated quantity on to a conveyer, and by this carried to the retort house.
Stabling.
Floor space required in stables per horse . . 120 square feet.
Width of stalls for horses 6 feet.
Width of building from wall to wall for stables 18 „
Height of stables 12 „
A horse requires about 30 to 40 Ibs. food per day.
Capacity of oat bins required per ton . . * . 75 cubic feet.
Capacity of hay lofts required per ton . . 500 „ „
Roads.
A layer of hydraulic concrete at least 8 inches thick, or a foundation of 12 inches of gravel, well rammed in, with 1 inch of sand on top, should be laid under paved roads.
Asphalt for roadways and for traffic should be 2 inches thick ; pavement of yards, covering of roofs, £ inch to 1 inch thick ; damp courses, J inch to f inch.
The road surfacing asphalt is crushed, heated to 275° or 300° F., spread uniformly where wanted, and stamped, rolled, and smoothed with heated irons.
Coke breeze for tar paving footpaths best made by using water with the tar to ensure the distribution through the whole of the breeze. Twenty-four gallons tar to the yard of breeze is sufficient.
RESISTANCE OF COMMON ROADS.
147
Grooves in Hobson's floor plates are best filled in with 112 Ibs. pitch, 85 Ibs. sand, and 56 Ibs. cement, with a little creosote oil on second boiling to make it pliable ; remainder filled in with tar concrete and rendered with 4 parts coarse sand to 1 part cement.
Resistance to Traction on Common Eoads. (F. V. Greene.)
Iron 10 Ibs. per ton.
Asphalt 15
Wood 21
Best stone blocks . . . . 33 Inferior stone blocks . .50
Average cobble stone . . . 90
Macadam 100
Earth ... . . 200
Resistance of Surface of Different Roads.
Stone tramway, exclusive of gravity . . . 20 Ibs. per ton. Paved roads ., ,, . . . 33 „ „
Macadamised roads „ „ .. 44 to 67 „ „
Gravel „ „ 150 „ „
Soft sandy or gravelly ground, exclusive of
gravity 210 „ „
The limiting gradients in ordinary roads are — Asphalt 1 in 60 ; wood, 1 in 25 ; macadam, 1 in 20 ; and granite, 1 in 15 ; but there are instances of macadam roads as steep as 1 in 6.
The average resistance to traction upon road tramways is about 30 Ibs. per ton with a minimum of 15 Ibs. and maximum of 60 Ibs. per ton.
Sir G. Molesworth stated (1895) that the greatest economical gradient for ordinary locomotives was 1 in 40.
To set out a curve make a template to sketch.
Where A 0 = the chord B D = versed sine.
A pencil held at B when the template is moved round and kept close to nails at A and C will mark the curve required.
L2
148 GAS ENGINEER'S POCKET-BOOK.
Unloading Materials.
To find Tractive Force of Locomotives,
T = tractive force in Ibs.
p = mean effective pressure in the piston.
d = diameter of cylinder in inches.
s = stroke in inches. D = diameter of driving wheel in inches.
T =
L>
Tractive Power of Locomotives. (Another rule.)
D = diameter of cylinder in inches.
L = length of stroke in inches.
T = tractive force on rails in Ibs.
P = mean pressure of steam in cylinders in Ibs. per square inch.
W = diameter of driving wheel in inches.
D'PL
~~
In Permanent Way Work,
Eight yards run of metals require —
2 lengths rail ..... cost (1894) £4 7,9. 9^7. per ton. 8 sleepers .»....,„ 2s. id. each.
2 pairs fishplates . . . . „ „ lOd. pair.
8 bolts at 1 Ib. (6 = 5 Ibs. 11 ozs.) . „ „ 1 1*. per cwt.
32 bolts (6 = 3 Ibs. 10 ozs.) . . „ „ 8s. lOrf. per cwt.
Labour costs, say, Is. per yard run.
Average weight of cast steel crossings (Vicker's patent), say 5 cwt. ; price, 1894, 32s. per cwt. Average cost of switchrails and stockrails, 1894, £5.
Materials Required per Mile of First Class Railway.
Steel rails, bull headed, at 85 Ibs. per yard 133J tons. Chairs, 8.872, at 50 Ibs ..... 86J „
Fishplates, steel clip, 352 pairs, at 40 Ibs. . 6£ „ Bolts and nuts, 1,408, at 1| Ibs.. . . 1 ton.
Spikes, 7,744, at 1| Ibs. . . . . . 4| tons.
Trenails, solid oak, 7,7.44 Keys, oak . 3,872 Sleepers, creosoted, 1,936
Tn relaying, the old materials may be credited at 55 per cent, of the cost of the new work-
RESISTANCE ON RAILWAYS. 149
Usual Type of Rail used on English railways. — The bull head of steel of 90 Ibs. per yard of an average length of 30 feet. Bessemer steel' is most used. Rails are drilled at ends, and the bolts are of steel. Test for rails is one to three blows of a 1-ton weight falling from various heights ; the rail, placed on bearings 3 feet 6 inches apart, must not show any signs of fracture or exceed a given permanent set ; sometimes a further test is made by hanging a dead weight of 40 tons in centre of 3 feet bearings, giving a maximum deflection of §-inch and no per- manent set after one hour's suspension.
Resistance of Curves. (Morrison.)
W = weight of vehicle.
R = radius of curve.
F = coefficient of friction of wheels on rails = '1 to *27
according to weather.
D = distance of rails apart from tread to tread. L = length of rigid wheel base.
WF(D + L) Resistance due to curve =
Elevation of Outer Rail on Curves.
Width of gauge in feet x velocity in miles per hour2 t eievation in
1-25 radius of curve in feet = j inches.
Axle Tests are that they should be placed on solid bearings 3 feet 6 inches apart, and subjected to five blows of a 2,000 Ibs. weight falling 20 feet, the axle being reversed after each. For wagons the ultimate tensile resistance should be 35 to 40 tons and 25 per cent, elongation in three inches.
Resistance of Trains,
W = weight of carriage without wheels and axles.
iv = „ „ wheels and axles.
D = diameter of wheels on tread.
d = „ „ journal.
F = coefficient of axle friction = say -035 with grease, '018 with
oil. f = „ „ rolling friction = about '001.
R = resistance of vehicle =/ (W + w) + ( WF ^
150
GAS ENGINEER'S POCKET-BOOK,
Crane Hooks, deduced from Experiments at London and North Western Kailway Company's Works,
/Diameter of link of chain in jths of an inch \ == working loadintomjf
V s /
0= diameter of chain.
1* (1-15 times diameter due to twice area of 0 up to 10 tons.
~ 1 1-2 _ „ „ „ „ „ „ „ „ above 10 tons. A = 3 X Je + C, B = £ A + -9 C, E = If A, D == A X '8. S =A x i, T = Axi, R = A, M = C, F = C.
HYDRAULIC CRANES, 151
BETORT HOUSE.
Best site for a Gas Works is the lowest point to be served, and, at the same time, close to the point of delivery of the raw material, such as a railway, canal, or river.
Average consumption per head 2,000 cubic feet per annum in large towns ; 1,600 cubic feet per annum in medium sized towns ; 1,000 cubic feet per annum in small towns.
Area of ground required for 7,000,000 cubic feet per day, 17 acres inclusive. (A. Colson.)
Hydraulic Power pressure usually adopted 700 Ibs. per square inch.
Old Beckton Hydraulic Cranes, nine in number, lift a total weight of 20 cwt. each — designed to discharge 40 tons an hour with a lift of 60 feet. Two horizontal high pressure pumping engines equals 75 horse- power each, with 17 inches diameter and 17 feet stroke accumulator — each engine would work the nine cranes ; but with a lift of 90 feet, as afterwards arranged, both engines are required. Cranes are multiplied 10 to 1, lifting chain travelling at 60 feet in 10 seconds, and the ram 6 feet in same time. Even with 90 feet lifts the cranes can easily lift 40 tons per hour, and have done considerably over that quantity. On the same pier are six steam cranes of the best type, requiring two 30 horse-power boilers to keep them going, whereas, with hydraulic power, two 20 horse-power boilers work one pair of pumping engines sufficient to actuate six cranes.
The practical efficiency of the distribution of hydraulic power in towns may be taken as 50 per cent, to 60 per cent, of the power developed at the works.
Loss of head due to velocity in hydraulic pipes
(Gallons per minute)2 X length of pipe in yards 3 X diameter of pipe in inches
Friction of the ram of an accumulator may be taken as 2| per cent. Friction in steam engine pumping into accumulator may be taken as 8-3 per cent.
Thickness of Hydraulic Cylinders.
Where d = external diameter of the cylinder in inches, D = internal diameter of the same, also in inches.
Loss of power by multiplying gear upon hydraulic rams varies from 7 per cent, when direct acting, to 50 per cent, when multiplying 16 to 1.
Velocity of water in feet per second = 8 V height of fall in feet, where there is no deduction from the force for friction or other resistance.
152 GAS ENGINEER'S POCKET-BOOK.
Saving by use of Conveyor and Priestman Grab.
At a works using about 49,000 tons per annum —
Old style — In barge 4 men Gs. j
On ran 2 „ 6*. I per day.
On crane 1 man Gs. )
7 men plus wear and tear of trucks and run equals about 4d. per ton.
New style— In barge 1 man 4s. 5d. ]
Conveyor engine 1 „ 3s. 9<Z. I per day.
Crane 1 „ 4s. 5d. }
3 men
plus wear and tear of elevator, conveyor engine, fuel, and interest on £1,200 (cost of elevator, conveyor, arid engine), about l*80rf. per ton.
d.
Craneman . . . . = -45 per ton. Engineman and bargeman . = -60 „ ., Interest, wear and tear .. = '42 „ „ Coke, 6 sacks per day, and oil = '33 „ „
FST „ „ Average Composition of Fireclays.
Peroxide
Silica. Alumina, of Iron. Lime. Magnesia. Potassa. Titanic Acid. Soda. 65-0 28'0 4-6 0'3 0'35 1-2 0.25 0'3
Composition of Fireclay.
Silica (Si02) .... 59 to 96 per cent.
Alumina (A1203) . . ... 2 to 36 „ „
Oxide of Iron (Fe203) . . 2 to 5 „ „
Lime, Magnesia, Potash, Soda . traces.
The more alumina that there is in proportion to the silica, the more infusible the fireclay. (J. Hornby.)
Stourbridge clay consists of —
Silica . . . . 63-7 Alumina .... 22-7 Oxide of Iron . . .2-0 H0a 11-6
100-0
Silica in ordinary Stourbridge firebricks = 65 per cent.
„ „ „ Welsh „ = 95 „ „
Specific heat of fireclay . , , . = 0*21
FIREBRICKS.
153
Tests of Firebricks at Royal. Arsenal.
|
Cracked At. |
Crushed At. |
||||||
|
Stourbridge . Newcastle Plympton Dinas . . . Kilmarnock . Glenboig . . |
1,478 Ib 1,156 , 889 , 1,689 , 1.123 , 2,134 , 1,067 , |
s.p |
srsqt 5 J 5 > |
are ii |
ich |
2,400 It 1,156 1,512 2,666 1.288 3,378 1,556 |
is. per square inch > »> »> « 5 » JJ •»» > 5' J> J> > J> » 5> |
|
) »» J> }» |
Cubes 1J inch sides, cut from soaps, were used and placed between pieces of sheet lead.
Fireclay Blocks Weigh per 100.
|
Inches. |
|||||
|
18X 9x3 24xl6X3£ 24x12x31 |
1 3 2 |
8 17 19 |
3 1 1 |
0 0 0 |
I Ellis and Grahamsley's, r Newcastle. |
|
12X 9X 6x3g |
1 |
15 |
0 |
0 |
I Wplssh |
|
9x 9X 6x3| |
1 |
3 |
0 |
0 |
|
|
12 X 9X 6X3§ |
1 |
11 |
2 |
1 |
Mobberley and Perry's. |
General Notes.
Ewell bricks are soft and not suitable for use where clinker bars are liable to be used, and should be set in Ewell loam.
Dinas firebricks fuse at about 3,880° to 3,930° F.
Firebricks from magnesia are being made, and recommended for very high heats, containing 95 to 97*8 per cent, pure magnesia ; they are set in a mortar made up of magnesia powder.
About J ton of fireclay is required per 1,000 Newcastle firebricks used.
If there be a thick joint or the broken corner of a brick where the flames from the furnace can get a hold upon, it will rapidly hollow out the brickwork at that point ; joints should therefore be very thin. Fireclay suffers no deterioration of quality from rain.
Twenty-one cubic feet of dry ground fireclay firmly packed = 1 ton ; ] 7£ cubic feet of blocks = 1 ton.
Retorts.
A good retort will sound metallic when struck, but if under-burnt or unduly cracked will give a dull sound.
H. Eeissner's Rule (Berlin Gas Works), 15 per cent, retorts in reserve in midwinter.
For machine stoking with 20 feet through retorts, Mr. _ West suggests a space of 21 feet 6 inches in front of beds each side at least, and 18 feet extra length from the centre of the end retort to enable the machines to be run out of the way.
154 GAS ENGINEER'S POCKET-BOOK.
The lowest point of the roof trusses should be 32 feet high from stage or floor line, at 11 feet from face of retort stack.
Height of tie-beam of roof in retort house should be at least 20 feet above floor line.
It is best not to allow floor joists in stage retort houses to bear upon the brickwork of the setting, owing to the great expansion and contraction of the latter.
Openings in the roof of retort houses near the eaves have been objected to as likely to drive the smoke downwards.
The openings in side walls of retort houses for ventilation should be above the level of the top of beds.
Provide as few doorways on floor line as possible in retort house.
Concrete under retort settings should be at least 1 foot below floor line.
Space in front of benches should be 22 feet or 25 feet if machinery is to be used.
It is likely to be cheaper to build the retort house of sufficient width to erect upon the stages the ordinary coal hoppers' and bins, from which the coal can be elevated direct to charging hopper at any part of the machine's progress along the stage, by an elevator attached to the machine. (A. F. Browne.)
Mr. Wyatt's Eule — 1 foot run of retort house per ton carbonised per day or 6,000 cubic feet with floor area of 1,000 feet per ton per day, and costs 18 per cent, of total capital at a rate of 4d. per cubic foot all provided.
Drain pipes to stoke-holes 9 inches diameter best laid with a fall of 3 inches in each 100 feet run, with 3 feet x 3 feet manholes to about every 100 feet (1 foot 9 inches of ground above the shallowest end).
The loss of power in distributing energy by compressed air equals 60 per cent.
Heat of one bed of retorts has heated a boiler 3 feet 6 inches diameter 9 feet long after heating the retorts, but this heat would have been better utilised if heating the retorts.
A temperature of 1,500° F. is often found in flues of moderate sized works.
Jointing for Mouthpieces to Clay Eetorts. — Two parts of sulphate of lime mixed with water, mixed well with six parts iron borings, with solution of sal-ammoniac, or three parts fireclay and 1 part iron borings (by weight) mixed with ammoniacal liquor.
Cross Tie Bods to Benches should be capable of resisting a breaking strain of 60 tons, and longitudinal tie rods 100 tons, it is practically impossible to prevent the expansion of a setting when first lighted up, and the tie rod nuts should be only hand tight, and should be slackened if found necessary.
End Buckstaves for Stage Setting should be 12 inches X 5 inches H iron, 4 at each end, and tie rods to same 2 inches diameter.
The top of a setting should be well covered or blanketed to prevent loss of heat by radiation.
Division walls of settings should be not less than 18 inches thick.
Space around Eetorts should not be more than 4 inches wide at any point in clay retort settings.
SETTINGS. 155
Clay retorts should be not less than 3 inches thick.
Smooth inside surfaces to retorts assist in preventing the accumu- lation of carbon and in its subsequent removal.
No setting should be used until at least 14 days after completion, and then gradually heated.
Twenty-one inches X 15 inches X 20 feet D retorts will easily carbonise 5^ cvvt. of Newcastle coals in 6 hour charges.
Through retorts are more economical than singles.
Circular retorts allow a large space above the charge, and are therefore bad.
The use of Thicker Walls in front of the bench has been advocated for the stoppage of the ascension pipe trouble.
Coke is sometimes removed hot by a conveyor under the mouth- pieces, and carried by it to an elevator where it is quenched by water from a perforated pipe, raised and piled in place, the elevator being so arranged that a swivel spout at the top allows it to be placed where desired.
The Size of the Mouthpiece should never be made, in any direction, smaller than the retort, as the coke can then be easily removed with- out jamming ; neglect of this precaution has caused the mouthpiece to be removed when drawing coke with machinery.
" Use plenty of walls to support retorts, and of good thickness, the small increased quantity of fuel required to heat them is more than compensated by the life of the retorts and setting generally."
" The brickwork in a setting should only be sufficient to uphold the retort, and to be of as small an area as possible at many points rather than large areas at few points."
Allow 25 square inches Air Space per retort between fire bars in open hearth furnaces.
In ordinary furnaces allow plenty of room above the fuel so that the CO may be converted into C02 before it passes among the retorts, say equal to the area of the fuel.
Ordinary furnaces evaporate 12 cubic feet of water per 24 hours.
With coal in furnaces, more space in flue ways required with increased supply of air.
About 50 per cent, of the heat generated in an ordinary furnace escapes unused up the chimney.
Allow about twice the theoretical quantity of air to ordinary furnaces, or some of the CO will pass away without being converted into C02
Each 3 Ibs. C requires 8 Ibs. 0, or 40 Ibs. (525 cubic feet) of atmo- spheric air, for complete combustion.
To estimate furnace efficiency : —
If T = temperature of smoke gases, t = temperature of air, c = specific heat of a cubic metre of CO2 (= up to 150° C. = 0'41, from 150° to 200° =0-43, from 200° to 250°= 0'44, from 250° to 300° = 0-45, from 300° to 350° = 0'46), c = specific heat of a cubic metre of 0 or N (about 0'31), then the loss of heat, x, in the furnace for every kilogramme of carbon burnt, expressed in calories,
is a? = 1-854 (T - f) c + 1-854 (T - f) 100~M C.
156 GAS ENGINEER'S POCKET-BOOK.
Calorific value of 1 kilogramme carbon is 8080 calories ;
therefore 'r = proportionate heat lost by fire gases.
oOoO
1 kilogramme carbon forms 1-S54 cubic metres of C02 at 0° C. and 760 minimum pressure. (Dr. G. Lunge.)
Structural Cost per Mouthpiece of Different Settings, (W. R. Chester, 1894.)
£ s. d.
Ordinary settings 14 0 0 life 500 days.
Klonne gaseous fired setting . . 32 4 (5 ,,300 „
Siemens „ „ „ 25 50 „ 104 „
\Vest ' „ „ „ . . c 27 17 0 „ 406 „
Siemens- Foulis gaseous fired setting . 27 15 0 „ 500 „
Chester „ „ „ . 17 0 0 „ 500 „
Materials Required for a Regenerator Setting of Nine D Retorts
(13£ inches x 20 inches x 20 feet long, 4| inch walls). From springing of furnace arch to level of first line of retorts : —
Stourlridge Goods.
9 inches x 2£ inches x 4£ inches = 1010 Ewell N.N. 1664.
9 „ x2 „ x4£ „ = 120 9 172.
9 „ xli „ x4i „ = 230
9 ins. x 2£ ins. x 2£ ins. Clubs = 110
Bevel side = 100
Bevel ends = 200
Feather edge = 100
Arch = 30
From level of first line of retorts : —
Stourbridgc Goods.
9 inches = 822
14 „ = 16
2 „ = 172
li „ = 237
1 inch = 82
Bevel ends =146
„ sides = 62
Clubs = 128
Arch = 145
Feather edge = 392
REGENERATIVE FURNACES. 157
From stage line : —
'Stourbt'idffe Goods.
14 inches = 64 Ewell.
9 „ = 2212 S.S. 9" = 460.
3 „ =44 N.N. 9" = 250.
2 „ = 216 N.N. arch = 700.
H ., = 224
1 inch =110 Clubs = 184
Feather edge = 742 Bevel sides = 144 „ ends = 50 Arch = 118
Regenerative Furnaces. — Provide for a good depth of fuel.
The adoption of gaseous firing greatly increases the lives of the retorts.
Generator settings are those in which a portion of the heat given off by the furnace is utilised to heat the air for secondary supply.
Regenerator settings utilise the heat of the waste gases after they have left the setting proper.
Generator furnaces should be from 4 'to 6 feet deep, and of com- paratively even thickness, usually 4 to 6 feet long, and 2 to 3 feet wide. (J. Hornby.)
The introduction of gaseous firing with greatly enlarged combustion chambers has not only effected great economy of fuel, but has increased the durability of retort settings above 66 per cent., while wear and tear in furnaces has been reduced in a far higher' ratio.
Beds of retorts run two years continuously, when a few bricks in fur- naces, on clinker line, have to be cut out and replaced. (A. F. Browne.)
The yield per mouthpiece has been increased 30 per cent, by the introduction of Regenerative furnaces.
Allow a considerable depth of fuel in generator not less than 3 feet 6 inches.
The simplest arrangement of flues, if of sufficient length and area, is quite as satisfactory as more elaborate methods.
The gases in a retort setting should be made to travel so that the heat is evenly distributed among all the retorts and throughout their length.
It is equally necessary to provide a good system of distribution of heat as to get a good regeneration.
Slowness of travel and opportunity for the heat to pass through the material separating the waste gases from the air to be heated is the main point to be observed in designing regenerative furnaces.
A large number of inlets for secondary air and for CO from generator is advisable in combustion chamber arranged so that an intimate admixture may take place.
The principal point to aim at in regenerator settings is to have an equal distribution of the secondary air and the gas along the line
158 GAS ENGINEER'S POCKET-BOOK.
of the setting, so that combustion may be taking place in many places instead of in one only.
Long passages for the warming of secondary air not necessary, as dry air quickly absorbs heat when in contact with hot surfaces.
The combustion chamber should be sufficiently large to prevent any flames passing into the flues.
Roomy combustion chambers assist in equal distribution of high heats.
Heat should be applied at the bottom of a retort, where the coal lies, rather than to the top and sides, where it would injure the Illu- minating Power of the gas passing out.
Only a slightly excess quantity of secondary air above the theo- retical suffices to cause complete combustion of the gases in the combustion chamber.
About one fourth the available heat is produced in the generator of a regenerator setting.
It has-been suggested that the steam used at the bottom of a re- generative furnace should be superheated by passing through pipes surrounding the ash-pit.
Flues should be built of best firebricks only, and made absolutely tight, all cracks being repaired immediately noticed.
Pressure on retorts should be: reduced by fixing large-sized mains and avoiding all obstructions, and, if necessary, counterbalancing the gasholders in works where no exhauster is provided.
Main Flues are generally 450 square inches in small works, increas- ing to 1,500 square inches in large works..
Chimney required for 2,000,000 per day retort house, 4 feet 6 inches square inside and about 113 feet high. (A. Colson.)
Chimney area per ton of coal per day should equal 24 square inches.
Another rule says the flue and chimney area should be from 30 to 40 square inches per ton of coal carbonised per diem.
The flue entrance from each furnace should be about 12 inches square.
One square inch of damper space per mouthpiece usually sufficient if draught is good.
Good or bad chimney construction may cause a difference of 50 per cent, in the fuel account.
It is said that firebricks will increase the pull upon a chimney 33 per cent, over that where common red bricks are in use, and 66 per cent, over that where stonework is employed. This is probably owing to the excellent non-conducting properties of firebricks.
Chimneys from retort benches need only be lined with firebricks.
A draught of from ^ inch to |g inch necessary for high heats.
Chimneys to each bed allow an easy regulation of draught, but the same effect may be gained by the use of shield plates or thin walls, to direct the gases in all cases towards the chimney, and the use of a damper to each setting.
Division plates should also be fixed at the entrance to the chimney when currents of gases are meeting from each side. In all cases avoid collision between gases going in different directions. Chimneys of ample dimensions without a division plate have often proved inadequate when settings on each side have been alight.
HYDKAULIC MAINS. 159
A division wall carried up some 8 feet in the middle of a chimney having flues in each side serves to give the gases an upward current before meeting.
Fit up a small pipe in bottom of retort house chimney to attach a pressure gauge to indicate the vacuum in chimney. Nine-tenths equals moderate draught.
Lightning conductors should be of copper, £ inch diameter, or in bands, say H inch by ^ inch — the latter for preference. If of iron, either 1 inch round rods or in bands say 2 inch by § inch.
Newbigging'srule for retort house chimneys under 70 feet high equals 1£ square inch area per lineal foot of retort, or 15 square inches per mouthpiece.
Hydraulic Mains.
The size of the hydraulic main should be such as to allow of a sufficiency of liquid to rise in the dip pipes up to the maximum back pressure likely to occur.
It is absolutely necessary that the hydraulic main be kept level.
Hydraulic mains should be large, and separated as to water level for each bench, and made easily cleanable.
The hydraulic main should be sufficiently far from the bench, so that the heat of the latter may not form pitch in the former.
Provide plenty of handholes in hydraulic mains for removal of tar and pitch.
The heavy tar in the hydraulic mains, if kept long in contact with the gas, is liable to rob it of its lighter hydrocarbons, but if the gas be cooled gradually with the lighter tar, which would be deposited by it between 150° and 100° F., for a time the gas may absorb some of the lighter hydrocarbons, which, with rapid cooling and separation from the tar, would be lost, and in this way deposition of napthalene in mains and services may be avoided.
Hydraulic mains, should never be supported from the brickwork of the settings, as the unequal expansion of the latter causes them to rapidly get out of level, and the seals of the different dip pipes are thereby altered. They can be supported by rolled joists, which at the same time form the tie-rods at top of the bench, or upon brackets upon the upright buckstaves, or on cast iron columns in front of the bench division walls. The hydraulic main is sometimes fixed imme- diately over the rising pipes, but it then becomes subjected to con- siderable heat, and also prevents the easy cleaning of the ascension pipes.
A perforated plate is often used in the hydraulic main to help to separate the tar by friction.
A weir arrangement at the end of the hydraulic main, which reaches nearly to the bottom and is above the level of the liquor and just in front of the overflow, permits only the heavier liquid to run away, and consequently the seal remains a light one. The overflow should be square, and not round, so that the liquid can easily flow away.
The thickness of ascension pipes may be kept down to f inch without any detriment to their usefulness.
160 GAS ENGINEER'S POCKET-BOOK.
Jointing for Ascension Pipes. — Slaked lime or fireclay well pressed down.
Curves in rising and arch pipes should be as gradual as possible.
Keep all curves in arch pipes gradual, as sharp corners produce stoppages.
Ascension pipes should be at least 8 inches from face of brickwork.
Weight of 6-inch pipes and bends in ascension dip bridge pipes and covers to a setting of nine retorts 21 inches by 15 inches ; hydraulic main cover 9 feet 3| inches from under side of top of upper mouth- piece equals 4 tons 0 cwt. 3 qrs. 9 Ibs.
Dip pipes should be carried to, say, within 3 inches of the bottom of hydraulic main, so as to keep the liquid agitated at this portion of the main.
If the dip of the pipes in the hydraulic be kept at f inch, and provision made for a water seal instead of a tar one, most of the objections to dip pipes are removed.
Four or 5 inches of liquid is quite sufficient in the bottom of the hydraulic main, as then the whole of the liquor and tar is kept agitated by the passage of the gas, and the deposition of thick tar prevented, and constant cleaning out rendered unnecessary.
Dip Pipes with light seals give equal results to anti-dip pipes. (W. A. Valon.)
Mr. Valon has abandoned anti-dip pipes for J-inch seal, which he considers better, as, if the former were used, leaking retorts from over- exhaustion are very frequent.
The advantages of removing the dip-pipe seals : — Improved illuminating power, increased yield of gas, less carbon deposits and napthalene, better utilisation of the heats, longer life of the retorts, fewer stoppages in the ascension pipes, &c. (Ulysse Andre.)
A mouthpiece for a 21-inch by 15-inch D retort weighs about 3 cwt. 1 qr. 9 Ibs. (this is with a 6-inch round hole on upper side for outlet and four holes for fixing flange of rising pipe with bolts). Lid, cross-bar lever, &c. (Morton's lids) weigh about 78 Ibs. for same mouthpiece.
Joints in dip and rising pipes in sockets may be made with fireclay and iron borings wetted with ammoniacal liquor.
Join iron mouthpiece to clay retort with fireclay, iron borings, and sal-ammoniac.
Fireclay and iron borings wetted with ammoniacal liquor may be used on all socket joints as well as mouthpieces.
Foul main temperature often 130° F.
Foul main area should equal 125 per cent, area of connections in works.
The gas, on leaving the hydraulic main, should be allowed to flow slowly, and be kept at a temperature of about 140° F. in the collecting main ; then the small proportion of benzol serves to arrest the napthalene in the condensers. (MM. Poi^oi^ anci Renard.)
HYDRAULIC MAIN VALVE
161
Hydraulic Main Valve.
162
GAS ENGINEER S POCKET-BOOK.
Size of Connections Usual in Gasworks.
|
Make per Day. |
Make per An num. |
Diameter of Connections. |
|
22,000 |
4,000.000 |
4 inches. |
|
31,000 |
5,750^000 |
6 |
|
65,000 |
12,000,000 |
8 |
|
115,000 |
21,000,000 |
10 |
|
208,000 |
38,000,000 |
12 |
|
285,000 |
50,000,000 |
14 |
|
325,000 |
60,000,000 |
14 |
|
370,000 |
68,000,000 |
10 |
|
470,000 |
85,000,000 |
16 |
|
580,000 |
105,000,000 |
18 |
|
720,000 |
130,000,000 |
18 |
|
830,000 |
150,000,000 |
18 |
|
865,000 |
156,000,000 |
18 |
|
900,000 |
165,000,000 |
20 |
|
1,050,000 |
190.000,000 |
20 |
|
1,100,000 |
200,000,000 |
20 |
|
1,300,000 |
240,000,000 |
24 |
Herr Reissner's Rule (works connections). — Mains, velocity, 6-56 to 9'84 feet. For small mains allow lesser velocity.
CONDENSERS. 163
CONDENSERS.
Wyatt's Rule.— 136 cubic feet of structure inside walls, 850 to 1,000 gallons per diem.
Clegg gives 150 superficial feet per 1,000 feet per hour when the layer of gas is not more than 3 inches thick.
One hundred and fifty to 200 square feet condensing surface per 1,000 per hour necessary. (Butter field.)
Allow 5 square feet cooling surface with wrought iron mains per 1,000 cubic feet in air condensers from the outlet of hydraulic main to the outlet of condenser. (Herring.)
Newbigging says 10 square feet per cubic foot per minute.
Editors of "King's Treatise " say that, under ordinary conditions, with air condensers, a superficial area equal to 10 square feet per 1,000 cubic feet per day is required from the hydraulic main, 20 feet of length per inch diameter of this pipe should be in the retort house.
Messrs. Dempster and Sons recommend a surface of 100 superficial feet per ton o£ coal carbonised per day, but add that 120 feet would be better.
Another authority says a surface of 51 square feet is ample for cooling 35,000 cubic feet of gas in 24 hours, equal to 1 square foot per 650 cubic feet in 24 hours.
Atmospheric Condensers. — The pipes from the hydraulic main should have a superficial area of 10 feet per 1,000 cubic feet made per diem.
- Area required for condensation equals about 4 square feet cooling surface (air) per gallon of water yielded per ton.
In water tube condensers about 2^ square feet of cooling surface is allowed per 1,000 cubic feet.
Beckton Air Condensers.— Gas travels at the rate of 6-3 miles per hour, and has 4 square feet of exposed surface per 1,000 cubic feet gas made per diem. Formerly gas travelled at a greater rate (9 miles per hour), the tarry vesicles being broken up by friction against the side of main.
Herr Reissner's Rule. — 3-65 square feet of cooling surface per 1,000 cubic feet per 24 hours as a minimum. 4'56 square feet of cooling surface per 1,000 cubic feet per 24 hours is the best allowance.
General Notes.
At Rotherhithe gasworks, with a maximum make of 5,000,000, the- condensing surface is 6-76 square feet per 1,000 and the speed 655 feet per minute, but the final removal of tar is not effected until the gas1 reaches the washers.
Long pipe condensers, through which gas passes rapidly, will break up the tarry vesicles by the friction on the sides of the pipes, the rate of travel at Beckton being 15 to 20 miles per hour. Another method is to pass the gas three or four times through a series of fine orifices, causing it to impinge on a plate. This also breaks up the vesicles.
164 GAS ENGINEER'S POCKET-BOOK.
Another plan is to pass the gas slowly through large pipes and gradually cool and condense the tarry vesicles. Speed, say one mile per hour.
It is said that slow condensation, say four or five miles per hour, causes a decrease in the deposition of napthalene.
With annular condensers the inner air pipes should be fitted with valves to regulate the quantity of air passing through and to prevent undue condensation of the gas.
„ , m Quantity of Heat Lost by a Square
Excess of Tempera- Unijfc f Exterior surface.
tureofGas. Air Water>
10° F. 8 88
20° 18 2GG
30° 29 5,353
40° 40 8,944
50° 53 1,3437
(Peclet.)
Condensation should be sufficiently complete to clear the gas of any redundant napthalene vapours, but should not be carried so far as to take out the hydrocarbons so necessary for increasing its illuminat- ing power. Contact of the gas with the tar should be as limited as possible, as this substance has been proved incontestably to cause dissolution of the light-giving hydrocarbons.
Gas should be cooled down to a temperature equal to, or even below, that of the coldest appliance it would have to traverse in its passage to the burner.
" The temperature of the gas should be rapidly brought down to about 60° F." (MM. Delseaux and lleuard.)
Another authority says : — " Gas should be cooled very slowly, and not below 50° F., or some of the lighter hydrocarbons will be deposited."
If napthalene ai dangerous preponderance is to be kept out of the gas, good condensation must be adopted, and maintained uniformly. It is possible to select a gas coal or mixture of gas coals which will yield a good illuminating gas with a fair minimum of uapthalene. The specific gravity of the tar affords a fair criterion of the amount of napthalene present in the tar.
" Mere cooling by unobstructed flow through pipes and chambers will not deprive gas of the whole of its suspended tar — its complete removal being only effected by means of friction." (A. F. Browne.)
" To prevent tar going forward to the scrubber, fix some wooden discs with holes of varying size, according to the make of gas, and between them some grids constructed of 1-inch and ^-inch bars set f inch apart, so that the whole of the gas as made is forced through the hole in the disc and impinges upon the iron grids." (W. R. Cooper.)
At 14 inches pressure 9,000 cubic feet of gas per hour will pass through a hole 1 square inch area.
So long as the temperature of the tar is above 90° F. there is no fear of clogging of perforated plates used for separation of tar from
TAR AND LIQUOR TANKS. 165
liquor, the plates being said to increase the illuminating power owing to the retention of the napthalene vapour.
After the tar has been separated from the gas it is well to ensure a prolonged association of the gas with its aqueous vapour, which, when later on condensed, consists of 8 or 9 oz. liquor containing much C0.2 and H2S.
Tarry vapours are more easily condcnsible under pressure.
It has been proposed to use atmospheric condensers sufficient for mid-winter use, and supplement these in summer by the use of water- tube condensers.
Friction tends to the deposition of napthalene, especially at low temperatures ; therefore anything rough on inside of pipe should be removed and easy bends always used where possible. Small mains likewise cause deposition of napthalene.
Condenser mains should have a fall of 1 inch per 9 feet length.
The weight of wrought iron mains is only about one fourth to one fifth that of cast iron mains of equal calibre, and they are quite strong enough for use above ground and where they can be examined for rusting, <fcc., and above moderate sizes are cheaper than cast iron.
Works mains may be made o£ wrought iron or steel, 20 feet long, with L iron flange joints.
Byepasses should be fixed to each piece of apparatus in the works.
All valves and blank flanges in works should have wells dug out around them with brick or timber sides, 'and timbers laid over them with £-inch blocks to keep them slightly apart.
Cost of fitting up 12-inch pipes, eight tiers high, to form condensers, l\d. per yard run of pipe (1893) ; this included fixing vertical struts and making lead joints.
A small balanced holder at outlet of condensers serves to prevent any oscillation on the retorts, and is especially useful where more than one retort house is worked from one exhauster.
Give mains in works inclination of from \ inch to 1 inch per pipe.
Allow a fall of 1 inch in 9 feet in works mains containing much tar.
Newcastle coal yields about 12 gallons water per ton. Derbyshire ., ., „ 2G „ „ „ „
TAB TANKS— LIQUOR TANKS.
Tar and liquor tanks should be of sufficient capacity to hold 850 gallons per ton per day ; or, say, five or six weeks' make.
Tar and liquor storage for 2,000.000 plant, 500,000 gallons, or four weeks' make. (A. Colson.)
One ton coal makes about 28 gallons 10 ounces liquor.
Allow not less than space for six weeks' production in tar and liquor tanks.
Tar and liquor tanks should equal four to six weeks' stock as a minimum. (Herring.)
Cover tar and liquor tanks to prevent escape of the ammonia gas, and danger from fire.
166 GAS ENGINEER'S POCKET-BOOK.
BOILERS, ENGINES, PUMPS, AND EXHAUSTERS, Exhauster Plant,
A horse-power (H.P.) is the quantity of work equivalent to the raising of 33,000 Ibs. through 1 foot in 1 minute, or to equivalent motion against resistance.
This is the usual unit by which the power of any steam engine is calculated.
To calculate horse-power of any engine : —
P = The mean effective pressure of steam in Ibs. per square inch.
A = The area of the piston in square inches. If the piston rod runs through cylinder its area should be deducted ; if only on one side of piston, half the area should be deducted.
L = Length of stroke in feet.
N = Number of strokes per minute = revolution per minute X 2.
H.P. = Horse-power of engine
HP- PLAN 33,000
Nominal horse-power (N.H.P.). — Ten circular inches of piston -area are usually provided for each N.H.P.
Brake horse-power (B.H.P.) is the actual power given off by an engine at the end of its crank shaft or rim of flywheel.
Unit of heat, or British Thermal Unit (B.T.U.), is the amount of heat required to raise 1 Ib. of water 1° at 39'1°
Joule's mechanical equivalent of heat equals 778 foot-pounds.
To raise 1 Ib. of water 1° F. requires the same energy as to lift 1 Ib. weight through a height of 778 feet, or 778 Ibs. 1 foot.
Mechanical efficiency of a steam engine, about 85 to 90 per cent.
Thermal „ ,, „ „ 10 to H .,
Thermal „ gas ,, „ 18 to 23 „
Wyatt's Rule. — 120 cubic feet of building to house boilers and details, and floor area 385 superficial feet per ton per day. Cubical contents of boilers (net outside measurements) not less than 5 cubic feet per ton per day.
To house engines and exhausters 105 cubic feet, or 3 square feet per ton per diem.
Herr Reissner's Rule. — Exhausters. Have one in reserve at each works.
HORSE- POWER REQUIRED TO WORK EXHAUSTERS. 167
Horse Power Required to Give 24 Inches Pressure,
(G wynne & Co.)
|
Cubb Feet per Hour. |
H.P. Required. |
Revolutions per Minute. |
Cubic Feet per Hour. |
H.P. Required. |
Revolutions per Minute. |
|
2,200 |
A |
250 |
63,000 |
6 |
75 |
|
3,000 |
i |
250 |
68,200 |
7 |
75 |
|
5,300 |
i |
230 |
73,500 |
7 |
75 |
|
10,500 |
i |
200 |
78,700 |
8 |
75 |
|
15,700 |
2 |
150 |
84,000 |
8 |
70 |
|
21,000 |
2 |
100 |
94,500 |
9 |
70 |
|
2(5.200 |
3 |
95 |
105,000 |
10 |
68 |
|
31,500 |
3 |
85 |
126,000 |
12 |
63 |
|
36,700 |
4 |
85 |
147,000 |
15 |
61 |
|
42,000 |
4 |
85 |
160,000 |
16 |
60 |
|
47,200 |
5 |
84 |
180,000 |
19 |
60 |
|
52,500 |
5 |
80 |
210,000 |
20 |
60 |
|
57.700 |
6 |
75 |
300,000 |
30 |
60 |
Exhausters improve the yield of gas about 11 per cent, without deteriorating the quality, and with cannel coals the improvement is still greater.
Exhausters should work with a minimum amount of power, and have as few parts to get out of order as possible, and at the same time give a steady pull without oscillation.
Exhausters only pass 75 per cent, of estimated quantity by measurement.
Theoretical Horse-Power Required to pass Gas at Various Pressures
without any Allowance for Friction of Exhauster.
(Edwin B. Donkin, 1894.)
|
Size. |
TOTAL PRESSURE OF GAS IN INCHES OF WATER. |
||||||||||
|
fi In. 9 In. |
12 In. |
15 In. |
18 In. |
20 111. |
24 In. |
30 In. '36 In. |
40 In. |
50 In. |
|||
|
5,000 |
0-08 |
0-12 |
0-16 |
0-19 |
0-24 |
0-26 |
0-31 |
G'39 |
0-47 |
0-53 |
0-66 |
|
10,000 |
0-16 |
0-24 |
0-31 |
0-39 |
0-47 0-53 |
0-63 079 |
0-95 |
1-05 |
J-31 |
||
|
15.000 |
0-24 |
0-36 |
0-47 0-58 |
0-71 0-79 |
0-94 1-18 |
1-42 |
1-58 |
1-97 |
|||
|
20,000 |
0-31 |
0-47 |
0-63 |
0-79 |
0-95 |
1-05 |
1-26 1-58 |
1-90 |
2-10 |
2-63 |
|
|
25,000 |
0-39 |
0-59 |
0-79 |
0-98 |
1-18 |
1-31 |
1-58 1-97 |
2-37 |
2-63 |
3-29 |
|
|
30,000 |
0-48 0-71 |
0-94 |
1-18 |
1-42 |
1-57 |
1-89| 2-36 |
2-83 |
3-15 |
3-94 |
||
|
40,000 |
0-62 0-94 |
1-26 |
1-58 |
1-90 |
2-10 |
2-52J 3-15 |
3-78 |
4-21 |
5-26 |
||
|
50.000 |
0-79 1-1* |
1-58 |
1-97 |
2-36 |
2-63 |
3-15 |
3-94 |
4-73 |
5-25 |
6-57 |
|
|
60,000 |
0-94 |
1-41 |
1-89 |
2-36 |
2-84 |
3-15 |
3-79 |
4-73 |
5-67 |
6.30 |
7-89 |
|
80,000 |
1-24 |
1-8-1 |
2-52 |
3-16 |
3-80 |
4-20 |
5-04 |
6-30 |
7'56 |
8-42 |
10-5 |
|
100,000 |
1-58 2-37 |
3-16 |
3-94 |
4-73 |
5-26 |
6-31 |
7-89 |
9-47 |
10-5 |
13-15 |
|
|
150,000 |
2-37) 3-54 |
4-72 |
5-90 |
7-09 |
7*87 |
9-46 |
11-8 |
14-2 |
15-8 |
19-7 |
|
|
200,000 |
3-16 4-74 |
6-32 |
7-88 |
9-46 |
10-5 |
12-6 |
15-8 |
18-9 |
21-0 |
26-3 |
|
|
250,000 |
3-95 5-92 |
7-90 |
9-85 |
11-8 |
13-1 |
15-7 |
19-7 |
23-6 |
26-2 |
32-9 |
|
|
300,000 |
4-74 7-11 |
9-4811-8 14-1 |
15-7 |
18-9 |
23-6 |
28-4 |
31-5 |
39-4 |
168
GAS ENGINEERS POCKET-BOOK.
Percentage to add to power shown on previous tables to ascertain horse-power required to drive exhausters at various pressures —
10.000 at 12 inches pressure . . 100 per cent.
20^00 „ 18 „ ... 90 „ „
50,000 „ 24 „ ... 70 „ „
100,000 „ 30 „ ... 50 ., .,
200,000 „ 36 „ ... 45 „ „
300,000 „ 50 „ ... 40 „ „
Size3 of Cylinders of Steam Engines required to drive exhauster, allowing 25 per cent, to 35 per cent, margin over power shown by previous tables.
|
Size of Exhauster. |
20,000 |
30,000 |
40,000 |
50,000 |
80,000 |
100,000150,000 |
200,000 |
|
|
In. |
In. |
In. |
In. |
In. |
In. |
In. |
In. |
|
|
Gas pressure |
18 |
20 |
22 |
24 |
26 |
30 |
33 |
36 |
|
Boiler „ 40 j |
diameter 4£ stroke 4£ |
6 6 |
6 12 |
7 12 |
10 14 |
101 15 |
12 18 |
14 18 |
|
M 6° { |
diameter stroke |
— |
— |
6 12 |
8i 14 |
10 14 |
!? |
12 18 |
|
( |
diameter |
|
|
|
7 |
10 |
10 |
|
|
"" ' |
stroke |
— |
— |
— |
12 |
14 |
14 |
18 |
In calculating size of exhauster required, the maximum rate of gas made per hour having been ascertained, 20 per cent, to 25 per cent, should be added to allow for the extra flow after the retorts are freshly charged, allowing also for the difference in temperature between gas at exhauster and at station meter. If a byepass is used to regulate the pressure or exhaust, a further percentage should be added, varying with the amount of the difference of pressure and exhaust.
In the best modern type of engine and good boiler, the combined efficiency is only 14-01 per cent, or £th of the heat value of the fuel used.
10 per cent, to 20 per cent, can be saved by properly applied steam jackets to engine cylinders. Covers should also be steam jacketed.
In the cylinder of a non-condensing steam engine, with saturated steam at 60 Ibs. pressure, the temperature is 293° F.. and at 100 Ibs. pressure 338° F.
Thickness of engine cylinders =
diameter x pressure of steam in Ibs. per square inch 2,400 if vertical, or 2,000 if horizontal
or,
-
4000
or,
Ends =
INDICATED HORSE-POWER. 169
Effective Pressure of Steam upon Piston Surface,
Boiler pressure assumed at 100 Ibs. per square inch. Different rates of expansions.
Effective Pressure.
Steam cut off at f of stroke = 90 Ibs.
3 » =80 „ i „ =69 „
» "3 » ' i}0 M
» =40 „
To Calculate the Indicated Horse-Power of a Steam Engine,
Eadius of cylinder2 equals I.H.P, at 42 Ibs. mean pressure and 250 feet per minute piston speed.
Any other pressure and speed may be calculated from above by direct proportion.
170
GAS ENGINEER S POCKET-BOOK.
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BOILERS.
171
Proportions of Steam Boilers per Nominal Horse-Power,
1 cubic foot water per hour.
1 square yard of heating surface.
1 „ foot of fire grate surface.
1 cubic yard capacity.
28 square inches of flue area.
18 ., „ „ „ „ over bridge.
13£ }) „ of chimney area.
L x D (in feet)
= H. P. nominal of any boiler approximately.
for Examining the Data when Designing a Steam Boiler, (Prof. A. Huet.)
Pounds coal burnt per hour . . per 1 square foot grate surface.
Grate surface per boiler heating surface.
Boiler heating surface square feet per pounds water evaporated
per hour. Pounds water evaporated . . per pounds coal burnt.
Total
should equal Total
Working Strength of Solid Wrought Iron and Steel Cylinders to Resist Internal Pressure.
|
Working Pressure in Lbs. |
Working Pressure in Lbs. |
||||
|
Diameter. |
per Square Jnch. (Excess of Internal over External Pressure.) |
Diameter. |
per Square Inch (Excess of Internal over External Pressure.) |
||
|
Inches. |
Iron. |
Steel. |
Inches. |
Iron. |
Steel. |
|
12 |
1,267 |
1,767 |
00 |
230 |
321 |
|
18 |
845 |
1,177 |
72 |
211 |
294 |
|
24 |
033 |
884 |
78 |
1 95 |
272 |
|
30 |
507 |
707 |
84 |
181 |
252 |
|
36 |
422 |
589 |
90 |
109 |
235 |
|
42 |
3(52 |
505 |
9(5 |
158 |
221 |
|
48 |
317 |
403 |
102 |
149 |
208 |
|
54 |
282 |
393 |
108 |
141 |
190 |
|
60 |
253 |
354 |
Thickness of cylinders, 1 inch. Working stress equals 7,000 Ibs. per square inch for wrought iron, 10.000 Ibs. per square inch for steel.
172
GAS ENGINEER S POCKET-BOOK.
Diagram showing Working Strength of Solid Wrought Iron and Steel Cylinders to Resist Internal Pressure per 1 inch thick.
(Deduced from Unwin.)
Steel Iron.
345 Diameter.
,/t.
BOILERS. 173
Notes on Lancashire Boilers. (M. Longridge.)
Abandon 6 feet grates if a shorter length will burn coal at 16 to 21 Ibs. per hour.
Keduce draught as much as the fuel will permit.
Obtain and use dry fuel and weigh ashes as well as fuel used.
Stop all leaks in boiler settings.
Aim to keep up C02 in chimney to 10 or 11 per cent.
The hotter the furnace the better.
An ordinary furnace requires 24 Ibs. of air or 300 cubic feet of air for the consumption of each 1 Ib. of coal ; if a blast or steam jet is used this may be reduced to 18 Ibs. or 220 cubic feet.
From 13 to 20 Ibs. of coal may be consumed per square foot of fire grate ; f foot of fire grate required to evaporate 1 cubic foot of water.
Strength of Boilers,
T x 0 Bursting strength of shell : P ae — — -
Where — >
P == bursting pressure in Ibs. p.er square inch.
T =± thickness of plate in sixteenths of an inch.
D =3 diameter of shell in feet.
C == for wrought iron (single rivetinsr) . . 1.097 ..... , (double ., ). . 1^372 i. steel ( ., „ ) . . 2.156
„ ). . 1,722
87-4 x T2
Collapsing pressure of tubes : P = -= — -— —
Li X JJ
Where—
P = collapsing pressure in Ibs. per square inch. T = thickness of tube in thirty-seconds of an inch. L = length in feet. D = diameter in inches.
Thickness. of fire bars, i to f inch ; space, § to \ inch ; inclination of bars, 1 in 10 to 1 in 12 ; height of dead plate above floor, 2 feet 8 inches ; minimum height of water over flue, 4 inches ; average height of water over flue, 9 inches ; inclination of boiler towards blow-off cock in setting, A inch in 10 feet.
Cornish or Lancashire boilers firegrate area X 4 = H. P.
Cornish or Lancashire boilers usually require 7 square feet heating surface per horse-power. Heating surface should be 20 times, and never less than 10 times, firegrate area ; or,
TT p Diameter of cylinder in inches 2 X \/ stroke in inches
' " 3-25
174 GAS ENGINEER'S POCKET-BOOK.
If more than one cylinder D2 = sum of the squares of the diameters of the pistons. Approximate rule for the nominal horse-power of cylindrical
L1 X D1 two-flued boiler is T: = H.P.
Safe Pressure on a Circular Boiler.
P = safe pressure in pounds per square inch. t = thickness of shell in inches.
/ = tensile strength of plate in pounds per square inch, v- 1 =for ordinary iron boiler plates, 20 tons. * \ = for steel boiler plates, 28 tons. (I = diameter of boiler in inches. li = in ordinary cases 6. k = factor of safety.
{= for single riveting 40 per cent. = for double riveting 60 per cent. = for butt joints 70 per cent. v = efficiency of the riveted joints.
Pressure in Boilers.
Circumferential bursting pressure is numerically equal to the area of the end X the pressure per square inch.
Bursting pressure longitudinally equals pressure per square inch X diameter in inches.
In a cylindrical shell the intensity of longitudinal stress is only half as great as the intensity of circumferential stress.
Safe Working Pressure on Boiler Furnace Tubes.
r. CX*» — (L + l) X D
3 8,000*
P should not exceed ^
P = safe pressure. t = thickness of plate in inches. L = length of tube in feet.
C = 60,000 if seams are lap-jointed, single riveted, and punched, D = diameter of tube in inches.
Safe Working Pressure on Iron Tubes (M. Longridge.)
50^2 Ibs. per square inch working pressure = j
t = thickness in 32nds inch. d = diameter in inches. L = length of tubes in feet.
BOILERS. 175
Duty Obtained from Coke-Fired Water-Tube Boilers.
Evaporative duty per pound coke = 10'05 Ibs. water.
Mean steam pressure per square inch = 143'3 Ibs.
Mean temperature of feed-water = 185° F.
Mean temperature of waste gases = 527° F.
Air supplied per pound of combustible = 22*39 Ibs.
Coke used = ashes and cinders = S'26 per cent.
Coke used = calorific value per pound = 13,186'9S British
thermal units. Heat communicated to water = 79'21 per cent.
A Flaw in the Thickness of a Boiler Plate or the least separation between two plates when bolted together is almost sure, if exposed to too strong a heat, to cause injury to the boiler.
Rate of Transmission of Corrected Heat through metal plates equals 2 to 5 British thermal units per hour per square foot of surface per 1° F. of difference of temperature. (D. K. Clark.)
A Boiler is said to have been Overheated when the boiler plate has become red hot at any given spot, and the phenomenon is recog- nised by the bluish shade the iron assumes when cold, due to the formation of a layer of oxide. Overheating alters the quality of the metal and disintegrates the joints, and, unless at once detected and remedied, it ultimately results in an explosion.
The reason generally assigned is an insufficient supply of feed- water.
If the boiler plates overlap, the transmission of heat is more or less impeded. Even a well made joint ought not to be exposed to too fierce a fire. (J. Hirsch.)
Proportion of Riveted Joints of Maximum Strength.
(D. K. Clark.):
Thickness of plate = 1
Diameter of rivets = 2
Pitch of rivets (single) = 5-J
Pitch of rivets (double) = 8
Diagonal pitch of rivets (double) = 6
Spacing (double) = 4£
Lap (single) = 6
Lap (double) = 10 J
Single riveted joint = about '56 of the plate.
Double „ „ = „ -7 „ „
Single butt straps should be 1§ times as thick as the plates.
Double butt straps should be each f times as thick as the plates.
Size of Rivets for Various Thicknesses of Boiler Plates. f and ^ inch plates— f inch rivets.
13
_ 1 8
-M
176 GAS ENGINEER'S POCKET BOOK.
Safety Valves.— According to the Board of Trade rules the area of a safety valve for a boiler working at 50 Ibs. pressure is 570 square inches per square foot of firegrate.
W Another rule is A = g^-p -f a
Where a = area of guides of valve, P = absolute pressure of steam in pounds per square inch, "W = weight of steam evaporated per hour in pounds, A = area of valve in square inches.
Theoretically, only 7*5 per cent, of the calories developed in the furnace of a boiler appears as work in the engine. (Hirsch.)
At a rough computation, petroleum burnt as fuel under a boiler should need only three-fifths the storage room of coal for the same duty ; and whatever further advantage calcium carbide has in point of compactness is mainly due to the superior efficiency of the gas engine to the steam engine.
A non-condensing engine requires 3 Ibs. of coal per I.H.P. per hour.
A condensing „ „ 2 Ibs. „ „ „ „
Set Boilers in mortar made of soft sand 2 parts, lime 1^ parts, sharp sand H parts, except where the bricks or lumps touch the boilers, when fireclay should be used.
Mr. C. Gandon found that the foundations of a boiler made of furnace clinker and cement, with three layers of firebrick bedded in fireclay, had caught fire from the flues, and the whole mass of the foundations was on fire.
Large flues around boilers cause a slow passage of gases.
Area of chimney = ™ <area of fireSrate in ^arofeet)
^/h eight of chimney in feet
Superheaters in boiler flues for superheating steam give a gain of 10 per cent, to 25 per cent., according to t}*pe of engine used.
In Lancashire boilers all furnace flue seams should be below the grate bars, longitudinal joints of shell butted and fitted with covers inside and out, double riveted zigzag, with outer rows twice the pitch of the inner ones.
For ordinary draught, when, say, from 20 to 25 Ibs. of coal is burnt per hour per square foot of firegrate, the average proportions to allow per I.H.P. are —
g square foot of firegrate. 2| „ of heating surface.
1£ cubic feet of water space. | „ of steam space.
English coal will evaporate 8 to 9'88 Ibs. water at and from 212° F. Scotch coal will evaporate (>'G9 Ibs. water at and from 212° F. Fuel consumption per I.H.P. may be anything from 1-3 Ibs., according to class of boiler, engine, and method of working.
Boiler Chimneys,
Allow 3J square feet chimney area for each full-sized Lancashire boiler, or -i square feet for a single boiler ; height of chimney same as others in neighborhood, preferably not less than 90 feet high.
CHIMNEYS. Dimensions of Chimneys. (E. Wilson.)
177
|
Area of Top |
||||||
|
Height of Chim- ney. Feet. |
Lbs. of Coal per Hour per 1 Foot Area at Top of Chimney. |
Height in Inches of Water Balanced by Draught Pressure. |
H.P. of each Square Foot of Chimney at 7 Ibs. Coal per H.P. |
Area of Top of Chimney in Feet per H.P. forl or 2 Boilers. |
of Chimney in Feet per H.P. where several Boilers work |
Area ofFlue in Feel H?P. |
|
together. |
||||||
|
30 |
78-24 |
•218 |
7-3 |
•146 |
•091 |
•182 |
|
40 |
90-35 |
•29G |
8-4 |
•126 |
•077 |
•155 |
|
50 |
101-01 |
•3G4 |
9-4 |
•113 |
•070 |
•140 |
|
60 |
110-65 |
- -437 |
10-3 |
•103 |
•064 |
•129 |
|
70 |
119-52 |
"5 |
11-2 |
•095 |
•059 ' |
•119 |
|
80 |
127-77 |
•58 |
11-9 |
•089 |
•055 |
•111 |
|
90 |
-135-52 |
•656 |
12-6 |
--•084 |
•052 |
•105 |
|
100 |
142-85 |
•729 |
13-3 |
•08 |
•05 |
•100 |
|
125 |
159-71 |
•911 |
14-9 |
•071 |
•044 |
•089 |
|
150 |
174-96 |
1-09 |
16-3 |
•065 |
•04 |
•082 |
|
175 |
188-98 |
1-26 |
17-6 |
•060 |
•038 |
•075 |
|
200 |
202-03 |
1-45 |
18-8 |
•056 |
•035 |
•070 |
|
225 |
214-20 |
1-34 |
20-0 |
•053 |
•033 |
•066 |
|
250 |
225-87 |
1-82 ,, |
21-0 |
•05 |
•031 |
•063 |
|
275 |
236-80-, |
1-99 |
22-0 ' |
•048 |
•03 |
•06 |
|
300 |
247-43 |
2-18 |
23-0 |
•046 |
•028 |
•057 |
Armstrong proposes from 20 to 40 per cent, above these sixes, and to allow for additions to boilers it would be advisable to exceed above sizes to that extent.
Proportion of Chimneys.
Diameter of base, ^th height.
Brickwork 9 inches thick for the top 25 feet.
Brickwork 14 inches thick from 25 to 50 feet from the top.
Brickwork 18 inches thick from 50 to 75 feet from the top.
Brickwork 23 inches thick from 75 to 100 feet from the top.
Increasing 4^ inches thick for every extra 25 feet.
Rule for Area of Chimney if 21 Ibs. of Coal are Consumed per Square Foot Grate Area per Hour.
Area of firegrate, in square feet, X 1£ + J height in feet = area in square feet.
Or, one-eighth to one-tenth grate area = area of chimney. Coal Consumed per Hour Up to 100 Ibs. . 500
1,000 2,000 3,000 4,000 5,000
Height of Shaft.
(50 feet. 100 120 140 160 180 200
Or, chimneys should'batter inside 1 inch in every 10 feet of height.
G.E.
178
GAS ENGINEER'S POCKET-BOOK.
To Find Size of Chimney Required.
For a low-pressure engine, when above 10 H.P., the area of the chimney in square inches should be 280 times the horse-power of the engine divided by the square root of the height of the chimney in feet. (Joshua Milne, of Oldham.)
Or, multiply the square root of the chimney height in feet by the square of its narrowest internal diameter in feet ; half the product will be the horse-power the chimney is equ-.il to.
Or, for circular chimney, the diameter = ' — — — — —
^/height in feet
Or, firegrate should <have 1 foot area per horse-power, one-fifth area of firegrate, gradually diminishing to a chimney which shall have one-tenth area of firegrate, is excellent proportion. (Cresy.)
Qr 2 X 112 X cubic feet evaporated per hour __ Sqliare inches N/height in feet area<
Coal Consumable by Chimneys of Different Sizes. (D. K. Clark.)
|
Chimney. |
Coal, per Hour. |
Grate Area. |
Chimney. |
Coal pei- Hour. |
Grate (•Area. |
||
|
Height. |
Diameter. |
Height. |
Diameter. |
||||
|
Feet. |
Ft. Ins. |
Lbs. |
Sq. Ft. |
Feet. |
Ft. Ins. |
Lbs. |
Sq. Ft. |
|
40 |
1 4 |
142 |
9-5 |
110 |
3 8 |
1777 |
118-4 |
|
50 |
1 8 |
248 |
16-5 |
120 |
4 0 |
2208 |
147-2 |
|
60 |
2 0 |
390 |
26'0 |
135 |
4 6 |
29G4 |
197-6 |
|
70 |
2 4 |
574 |
38-3 |
150 |
5 0 |
3858 |
257-2 |
|
80 |
2 8 |
801 |
53-4 |
105 |
5 6 |
4896 |
326-4 |
|
90 |
3 0 |
107(5 |
71-7 |
180 |
6 0 |
6086 |
405-7 |
|
100 |
3 4 |
1394 |
93-0 |
200 |
6 8 |
7920 |
526-6 |
Diameter =
height-; coals consumed, 15 Ibs. per square foot per hour.
Metropolitan Board of Works Regulations as to Factory Chimneys.
Base of shaft to be solid up to top of footings ; projection of footings equal all round, and to thickness of wall at base.
Width of shaft at base, just above footings : —
If square on plan, at least Jr,th total height.
If octagonal on plan, at least £th total height.
If circular on plan, at least ^th total height.
Batter at least 2^ inches in every 10 feet, or 1 in 48.
Brickwork at least 8£ inches thick at top and for 20 feet down, and increased 4£ inches for every 20 feet additional height ; firebrick lining to be separate, and not included in above thicknesses.
Cornice not to project more than the thickness of walls.
CHIMNEYS.
179
Velocity of gases up the chimney being proportional to the square root of the height, increased duty would be better obtained by larger diameter than by greater height.
The heavier the materials of which a 'shaft is built the greater would be its stability, the foundations being good.
Batter of chimneys may equal 1 in 3(5.
Theoretical draught power of chimneys with external air = 60° F.; internal heated air = 580° F. (coefficient in practice -3).
|
Height of Chimnev in Foot |
Draught in Inches of Water. |
Theoretical Velocity in Feet per Second. |
|
|
Cold Air Entering. |
Hot Air at Outlet. |
||
|
50 |
•367 |
40-0 |
80-8 |
|
60 |
•440 |
43-8 |
87-6 |
|
70 |
•514 |
47-3 |
94-6 |
|
80 |
•587 |
50-6 |
101-2 |
|
90 |
•6f>0 |
53-7 |
107-4 |
|
100 |
•734 |
56-G |
113-1 |
|
120 |
•880 |
62-0 |
123-9 |
|
150 |
1-101 |
69-3 |
138-6 |
|
175 |
1-285 |
74-8 |
149-6 |
|
200 |
1-468 |
80-0 |
160-0 |
|
225 |
1-652 |
84-8 |
169-7 |
|
250 |
1-830 |
89-4 |
178-9 |
|
275 |
2-020 |
93-8 |
187-6 |
|
300 |
2-203 |
98-0 |
196-0 |
(Bancroft.)
The wind pressure on chimney shafts may be taken -as acting upon the centre of gravity and in a horizontal direction, and the over- turning moment equals the height of the centre of gravity (7<) above the point at which it is desired to obtain the strength, as at a b, x vvind pressure on chimney ; the least moment of stability must therefore exceed this (/<>?' jig it re see next page).
The pressure of the wind will tend to move the centre of pressure on a b, towards the leeward side.
To obtain the moment of stability of any shaft take weight of shaft above a b x % a 1).
Kankine says a factor of safety of 2 is necessary for round shafts and of I for square shafts.
It has been said that the limiting position of the centre of pressure is permissible to be at one sixth of the diameter from the leeward side for square shafts, and one quarter of the diameter from the side for round shafts, only when the brickwork becomes infinitely thin.
Firebrick lining to boiler chimneys need not be more than one half, or at most two thirds, the total height.
If wind pressure on square shaft = 1 then ., „ „ hexagonal shaft = -75
„ „ ,, „ octagonal shaft = -7
v „ „ „ circular shaft = -5 (Bancroft.)
2T8
180
GAS ENGINEER'S POCKET-HOOK.
LIGHTNING CONDUCTORS. 181
Chimney shafts should not be joined to any other work of buildings, in case of settlement or expansion.
Grouting is not advisable, as wet mortar possesses little adhesive power ; and the building should not proceed at a greater rate than 2 feet to 3 feet per diem. Only one course of headers should be used in large chimneys to three or four of stretchers. Capping stones should be light and joined with copper cramps at joints, as iron rusts and expands, when the stone may split and fall.
Stock bricks will bear a heat of 600° F. without damage.
Higher heat at exit of chimney than 580° F. or 305° C. is wasteful.
Less exhaust than \ inch water bad.
580° F. gives a head of external air equal to half the height of chimney.
By the usual rule, the external diameter at base of chimney should be about ith of the height, and the batter A inch to \ inch per foot on each side.
It is frequently stated in treatises on chimney designs that the diameter at the base should be ^th to ^th the height, but, having regard to the paramount importance of width of base, the width obtained by this rule is insufficient.
For further remarks on chimney shafts, seo Bancroft on " Design of Tall Chimneys."
Lightning Conductors.
Copper is the best ; but, when corrosion is not anticipated, iron of larger dimensions may be used (conductivity of iron equals ith that of copper).
General dimensions of copper conductors : — Rods \ inch diameter, tubes j| inch diameter, \ inch thick ; or bands \\ inch wide § inch thick.
General dimensions of iron conductors : — Eods 1 inch diameter, bands 2 inches wide x f incli thick.
Radius of protection of lightning conductors equals height from ground.
Sir William Thomson's (Lord Kelvin's) note advocates the use of the flat (tape or sheet) form of conductor in preference to the tubular or solid; and, if copper be used, its weight should be about (5 oz. to the foot ; if iron, about 35 oz. It quotes Lodge's recommendation that the conductor should be connected with the water or gas mains if in any part of its course it goes near them, but concedes that independent grounds are preferable. It gives the usual advice as to electrical connection with masses of metal built into a building, and warns against the neighbourhood of small-bore fusible gas pipes and indoor gas pipes in general. It prefers clusters of points, or groups of two or three, along the ridge rod, to other arrangements, and regards chain or link conductors as of little use. That the area protected is one of a radius equal to twice the height of the rod from the ground, or even, as some conductor manufacturers aver, a radius equal to the height, is denied. No such thing as a definite area exists. That lightning follows the path of least resistance is also controverted, for, in exceptional instances, when the flash is of a certain kind any part of a building is liable to be struck, whether there is a conductor or not.
182 GAS ENGINEER'S POCKET-BOOK.
Lightning may also, contrary to what is generally held, strike twice in the same place. Doorways of barns, chimneys, and fireplaces are dangerous places, but the smaller articles of steel, such as knives, &c., have no influence on the path of discharge. The best made-ground for the earth-plates is, for some flashes, but a very poor one ; damp earth or running water are still the best terminations known.
Steam Pipes.
Thickness of steam pipe in IGths of an inch equals diameter (inches) + 4 up to 100 Ibs. pressure.
D P
Above this T = 7-777+ \ T = thickness in inches.
Steam should have a velocity of about 6,000 feet per minute through steam pipes ; same for ports of engine. To find diameter of steam pipes for any engine :
* / Sq. of cylinder diar. in inches x piston speed in feet per min.
<>.000
= The required diameter of steam pipe.
100 feet of 4-inch pipe would waste as much heat per annum as the consumption of 50 tons of coal would supply. With an efficient lagging it is to be supposed that most, if not all, of this would be saved. (Mr. Geipel.)
Allow 1 inch expansion in 50 feet in steam pipes.
A 4 H.P. engine requires only 2-inch diameter steam connections.
Exhaust Pipe,
To prevent undue back pressure velocity of steam should not be greater than 4,000 feet per minute. To find diameter of exhaust pipe :
Square of cylinder diameter x piston speed in feet per minute 4,000.
The square root of the quotient gives diameter of pipe in inches ; same for ports of engine.
Condensation,
The water required for condensation is about 20 times that required for the feed - approximate area of condensing surface = heating surface x 0'7.
Comparative Efficiency of Non-conducting Materials. (Emery.)
Wood felt 1-000
Mineral wool, No. 2 '8:52
., „ with tax '715
Sawdust -680
Mineral wool, Xo. 1 '07(5
Charcoal '632
Pine wood, across fibre '553
Loam, dry and open '550
Slaked lime '480
Retort carbon '470
Asbestos '363
Coal ashes '345
Coke in lump '277
Air space undivided '130
DISTANCE BETWEEN BEARINGS OP SHAFTS. 183
Diagram showing Span between Bearings of Shafts.
Feet, centres of Journals.
C = 6 0 = 4-5
From the rule S = C J/D»i
S =a span between bearings in feet. C '
where D = diameter of shaft.
( 5 to 6 for shaft, only, without pulleys. = \ 4'5 to 5 for shaft, with ordinary number
{ of pulleys and wheels.
184
GAS ENGINEER'S POCKET-BOOK.
Non-Conductors for Steam Pipes. (Prof. J. M. Ordway.)
|
Substance, I Inch Thick. Heat Applied, 310" F. |
Lbs. Wate Heated 10° F. per Hour through 1 Sq. Ft. |
Substance, 1 Inch Thick. Heat Applied, 310° F. |
Lbs. \Val8i Heated 10° F. per Hour through 1 Sq. Ft. |
|
Loose wool . |
81 |
Air alone . . . |
48-0 |
|
Live- geese feathers |
9-6 |
Sand .... |
62-1 |
|
Carded cotton |
10-4 |
Best slag wool . . |
13-0 |
|
Hair felt . . . |
10-3 |
Paper .... |
14-0 |
|
Loose lampblack Compressed ditto . . |
9-8 10-6 |
Blotting paper, wound tight |
21-0 |
|
Cork charcoal White pine charcoal . |
11-9 13-9 |
Asbestos paper, wound tight |
21-7 |
|
Anthracite coal powder |
35-7 |
Cork strips, bound on |
14-6 |
|
Loose calcined mag- |
Straw rope, wound |
||
|
nesia |
12-4 |
spirally . . . |
18-0 |
|
Compressed calcined |
Loose rice chaff . |
18-7 |
|
|
magnesia . |
42-6 |
Paste of fossil meal |
|
|
Light carbonate of |
with hair |
16-7 |
|
|
magnesia . |
13-7 |
Paste of fossil meal |
|
|
Compressed carbonate |
with asbestos . |
22-0 |
|
|
of magnesia . |
15-4 |
Loose bituminous coal |
|
|
Loose fossil meal . . |
H-5 |
ashes |
21-0 |
|
Crowded fossil meal . |
15-7 |
Loose anthracite coal |
|
|
Ground chalk (Paris |
ashes |
27-0 |
|
|
white) . |
20-6 |
Paste of clay and |
|
|
Dry plaster of Paris . |
30-9 |
vegetable fibre |
30-9 |
|
Fine asbestos |
49-0 |
Notes on Pumps.
A man exercises more power with an ordinary pump handle than with a crank and handle. The power exerted by an ordinary man in working a pump handle continuously must not be estimated above 25 Ibs. The suction and delivery pipes of pumps should not be less than one half the diameter of the barrels ; and if the length be great, they should be larger ; also with large pumps or pumps working fast it is well to have a greater proportion of pipe area (in some cases the pipe is made as large as the barrel). The suction pipe should also be larger than the delivery pipe, as in the suction pipe there is only the atmospheric pressure to overcome the friction, whereas in the delivery pipe there is the whole power of the pump. The following is a safe rule for the sizes of suction pipes. An advantage is gained by using a large suction pipe, even if the inlet of the pump be smaller than the pipe.
Inch, Inch. Inch. Inch. Inch. Inch. Inch. Size of pump 2 2£ 3 34- 4 5 6 Size of suction 1£ 17} 2 2" 2-£- 3 4
PUMPS.
185
These sizes hold good for double pumps, as each barrel draws alternately, and therefore the pipe need not be increased in size. In laying a long length of suction pipe make sure that it falls along its whole length from the pump towards the well. If there is any point higher than the pump end of the pipe it will form a pocket or trap from which it will be very difficult to draw the air. It is always desirable to have a foot valve in the suction pipe to retain the water when the pump is standing. To avoid concussion and equalise the working of the pump it is well to place a vacuum vessel on the pipe just before it enters the pump.
Formula for calculating the power required to raise water : — Gallons per minute x height in feet
= — = horse-power
Add for friction according to the machinery used and length of pipin Capacities of Pumps.
|
Dia- meter. Inches. |
Area in Inches. |
Displacement in Gallons per Foot of Travel. |
Dia- meter. Indies. |
Area ia Inches. |
Displacement in Gallons per Foot of Travel. |
|
* |
•0129 |
•0005 |
4* |
14-18 |
•6125 |
|
| |
•0490 |
•0021 |
44 |
15-90 |
•6868 |
|
I |
•1104 |
•0047 |
• 4| |
17-72 |
*7655 |
|
4 |
•19(53 |
•0084 |
5. |
19-63 |
•8480 |
|
£ |
•30(58 |
•0132 |
H |
21-54 |
•9348 |
|
t |
•4417 |
•0190 |
6| |
23-75 |
1-026 |
|
* |
•6018 |
•0259 |
B| |
25-96 |
1-121 |
|
1 |
•7854 |
•0339 |
6 |
28-27 |
1-221 |
|
4 |
•9940 |
•0429 |
6* |
30-67 |
1-325 |
|
1* |
1-227 |
•0530 |
6£ |
33-18 |
1-433 |
|
If |
1-484 |
•0641 |
6} |
35-78 |
1-545 |
|
U |
1-7(57 |
•0763 |
38-48 |
1-662 |
|
|
1* |
2-073 |
•0895 |
H |
41-28 |
1-783 |
|
If |
2-405 |
•1038 |
74 |
44-17 |
1-908 |
|
1* |
2-761 |
•1192 |
7J |
47-17 |
2-037 |
|
2 |
3-141 |
•1356 |
8 |
50-26 |
2-171 |
|
2£ |
9-646 |
•1531 |
8J |
53*45 |
2-309 |
|
2* |
3-970 |
•1717 |
&4 |
56-74 |
2-451 |
|
2f |
4-430 |
•1913 |
8f |
60-13 |
2-597 |
|
«4 |
4-908 |
•2120 |
9 |
63-61 |
2-747 |
|
2* |
5-411 |
•2337 |
9* |
67-20 |
2-903 |
|
2f |
5-939 |
•2565 |
94 |
70-88 |
3-062 < |
|
2£ |
6-491 |
•2804 |
91 |
74-66 |
3-225 |
|
3 |
7-068 |
•3053 |
10 |
78-54 |
3-393 |
|
8| |
7-669 |
•3313 |
IP* |
82-51 |
3-564 |
|
3* |
8-295 -3583 |
104 |
86-59 |
3-740 |
|
|
3f |
8-946 -3864 |
10f |
90-7(5 |
3-920 |
|
|
3^ |
9-621 -4156 |
11 |
95-03 |
4-105 |
|
|
N |
10-32 -4458 |
i'H |
99-40 |
4-294 |
|
|
3| |
11-04 -4769 |
114 |
103-8 |
4-484 |
|
|
3£ |
11-79 |
•5193 |
lit |
108-4 |
4-682 |
|
4 |
12-56 |
•5426 |
12 |
113-0 |
4-881 |
186
GAS ENGINEER'S POCKET-BOOK.
The following rule shows how to determine the dimensions of the feed pump : —
Let D = diameter of steam cylinder in inches.
L = length of stroke up to point of cut-off in inches. s = stroke of pump. d = diameter of pump.
r = volume of steam obtained from 1 cubic foot of water at the given pressure.
Then d —
Force pumps should be twice the diameter of the pipes in connec- tion.
Horse-power required to raise water equals quantity of water to be raised in gallons per minute X 10 X height to be lifted in feet divided by 33.000. Add ^ to f for losses by slip of valves and friction.
Table of Pedestal Proportions. (Unwin.)
|
Dia- meter ol Journal. Inches. |
Lengtli of Bearing. Indies. |
Height to Centre. |
Dianietei of Bolts. |
Size of Bolt Holes. |
Length of Base, |
Centres of Cap Bolts. |
Centres of Base Bolts. |
Thick- ness of Step at Bottom. |
|
1J |
3* |
2| |
1 |
1X1 |
8i |
•H |
** |
itoA |
|
2 |
3 |
2! |
i |
1X1* |
11 |
H |
<) |
f!i »t |
|
n |
3J |
3i |
1 |
1X1* |
13$ |
5* |
lOf |
fh ,& |
|
3 |
4 |
8| |
7 8 |
1 xi$ |
15i |
6J |
is* |
I ,* |
|
Si |
*i |
*4 |
1 |
»*xi| |
17i |
7 |
uf |
f ,i |
|
•i |
5 |
*i |
M |
1JX2 |
20 |
?j |
10i |
1?0 >^5 |
|
5 |
6 |
6 |
if |
l|X2i |
24 |
9§ |
19| |
* ,i |
|
6 |
7 |
7 |
i§ |
liX2J |
28^ |
Ht |
23^ |
il ,ii |
|
7 |
8 |
8* |
Two 1$ |
l|X2i |
— |
12-i |
— |
5 ,1 |
|
8 |
9 |
9* |
» H |
lfX2i |
— |
14 |
— |
3 ,1 |
|
<J |
10 |
10* |
» 1* |
1*X2J |
— |
1S| |
— |
-J ,1 |
|
10 |
11 |
11* |
» 1! |
2 X2| |
— |
17* |
— |
* ,1* |
|
12 |
13 |
13* |
» 2i |
2|X3J |
• — • |
21 |
— |
i ,1$ |
From seven inches upwards the pedestals have two bolts on each side, both in cap and base plate.
Length of Engine Journals.
The higher the speed the greater the length of journal required. At 150 revolutions per minute one diameter is sufficient ; at 1,500 revolutions per minute 6 or 8 diameters are better.
Coefficient of Friction with Dry Surfaces.
Metal on metal 0'15 to 0'20 Wood „ „ 0-25 to 0-30 Millboard ., 0.20
GEARING. 187
When polished steel moves on steel or pewter properly oiled the friction is about ^ of its weight ; on copper or lead \, on brass |.
Metals working on same metals give more friction than when on different metals.
3 /p x /,
Diameter of engine crank shafts = — — —
A,
P = pressure of steam on piston. I = length of crank in feet. K=80 for iron, 120 for steel.
Safe Speed for Flywheels.
Maximum safe circumferential velocity of cast iron flywheels is 80 feet per second. Speed should not exceed in revolutions per minute
1530
mean diameter in feet.
Width of Rim of Pulley for Belts of Various Widths. (Unwin.)
Ins. Ins. Ins. Ins. Ins. Ins. Ins. Ins.
Width of belt 2 3 4 5 G 8 10 12
Width of pulley 2f 3J 5 6 1\ 9£ llf 11
Thickness of edge of rim equals 0'7 thickness of belt + '005 times the diameter of pulley.
Radius of rim face equals 3 times to 5 times the breadth of rim.
Diameter of pulleys should not be less than 6 to 8 times the dia- meter of a wrought iron shaft suitable for transmitting the power transferred to the belt, and the diameter of the smaller of two pulleys should not be less than about 18 times the belt thickness.
Breaking weight of machine belting, leather, per square inch equals 1*9 tons.
Leather hose and driving belts for machinery treated with castor oil have been found to last longer, and when impregnated will not slip. A 3-inch belt treated with castor oil equals a 4|-inch belt without oil. and will last more than twice as long.
Proportion of Teeth of Wheels,
Depth = pitch x '75
Working depth = „ x '70 Clearance = ., x '05
Thickness = pitch x *4:5 Width of space = „ x -55 Play = „ x -10
Length b3yond pitch line = pitch x '35.
Common Proportion of Keys. (Unwin.)
Diameter of eye of wheel or boss of shaft = d Width of key = I = \d + -J Mean thickness of sunk key = t = \d + -J- „ „ key in flat = ti= ±d + i
188
GAS ENGINEER'S POCKET-BOOK.
In toothed wheah T. of tooth = -48 pitch. Width of space = '3 pitch. Height above pitch line = "3 pitch. Depth below pitch line = -4 pitch.
A good new leather belt has a tenacity of from 3,000 to 5,000 lbst per square inch of section.
Coefficient of friction is about "423 between ordinary belting and cast iron pulleys.
If leather belting has a tenacity of 1,000 Ibs. per inch of width the strength of a riveted joint may be taken at 400 Ibs., a butt-laced joint at 250 Ibs., and an ordinary overlapped laced joint at 470 Ibs.
Effective working stress of ordinary single belts 50 Ibs. „ „ light double 70 „
,, „ heavy double „ 90 .,
Diameter of pulley should be more than 100 times the thickness of the belts around it. Katio between two pulleys ought not to exceed 6 to 1. Convexity of pulleys equals ^ inch per foot in width.
Centrifugal action on belts may be ignored at ordinary speeds up to 3,000 feet per minute.
Internal friction in ropes driving pulleys is the principal destructive agent.
Breaking strain of good icpes = 4 tons per square inch. Working „ „ = 300 Ibs. per square inch.
Ropes should not be driven above 4,700 feet per minute.
Cotton appears to be best for driving pulleys.
It is said that belts should be made heavier and run more slowly than ordinary rules state to save cost in long run and prevent stoppages for relacing and repairing. At intervals of three months each belt'-should be scraped clean and dubbed.
Working Tension of Belts (Leather).
|
Thickness of Belt |
|||||||||||
|
(in Inches) . . |
T3n |
£ |
f |
T5n |
f |
rtr |
i |
T9a |
• I |
y |
t |
|
Tension in Lbs. |
|||||||||||
|
per Inch Width |
60 |
70 |
80 |
100 |
120 |
140 |
100 |
180 |
200 |
220 |
240 |
|
Single. |
D |
ouble. |
Usual Proportions.
|
Width of Belt (in Inches) . |
2 |
0 |
4 |
6 |
8 |
10 |
12 |
15 |
|
Thickness (Inch) . . . . |
0-14 |
•17 |
•20 |
•24 |
•28 |
•32 |
•35 |
•39 |
|
Working Tension in Lbs. |
||||||||
|
per Inch of Width . . |
45 |
55 |
64 |
78 |
90 |
101 |
110 |
124 |
ROPE GEARING.
189
Horae-power of different sized Manilla Eopes at different speeds
Working stress = ^th, breaking stress = ^th strength of splice.
Horse-powers.
5 10 15 20 25 30 35 40 45
ISO
140
130
00
50
30
5 io 15 20 25 30
Horse-powers.
45
190
GAS ENGINEERS POCKET-BOOK,
Width of Belts in Inches when-—
|
Velocity of belt in Ft, per Sec. |
The Horse-power Transmitted |
is |
||||||||
|
1 |
2 |
3 |
4 |
5 |
"J- |
10 |
15 |
20 |
25 |
|
|
1 |
15-7 |
31-4 |
47-0 |
63-0 |
||||||
|
2* |
6-3 |
10-6 |
18-8 |
25-2 |
31-2 |
4G-8 |
||||
|
5 |
3-1 |
6-3 |
9-4 |
12-6 |
15-6 |
23-G |
31-4 |
47-2 |
||
|
7| |
2-1 |
4-2 |
6-3 |
8-4 |
10-4 |
15-G |
21-0 |
31-2 |
42-0 |
52-4 |
|
10 |
1-5 |
3-2 |
4-7 |
G-4 |
7-8 |
11-8 |
15-7 |
23 -G |
31-4 |
39-2 |
|
12i |
1-3 |
2-5 |
37 |
5-0 |
G-4 |
9-4 |
12-G |
18-8 |
25-2 |
31-2 |
|
15 |
1-1 |
2-1 |
3-1 |
4-2 |
5-2 |
7-8 |
10-5 |
15-G |
21-0 |
2G-2 |
|
20 |
•79 |
1-6 |
2-4 |
3-2 |
3-9 |
5-9 |
7-9 |
11-7 |
15-7 |
19-G |
|
25 |
•63 |
1-3 |
1-9 |
2-6 |
3-1 |
4-7 |
6-3 |
9-4 |
12-G |
15-G |
|
30 |
1-1 |
1-6 |
2-2 |
2-6 |
3-9 |
5-2 |
7-8 |
10-5 |
13-1 |
|
|
35 |
1-3 |
1-7 |
22 |
3-4 |
4-5 |
G-8 |
9-0 |
11-2 |
||
|
40 |
1-5 |
2-0 |
2-9 |
3-9 |
6-9 |
7-8 |
9-8 |
|||
|
45 |
1-8 |
2-6 |
3-5 |
5-2 |
7-0 |
8'-8 |
||||
|
50 |
1-G |
2-4 |
3-2 |
4-7 |
G-3 |
7-8 |
||||
|
GO |
1-3 |
2-0 |
2-G |
3-9 |
5-2 |
G-5 |
||||
|
70 |
1-1 |
1-7 |
2'2 |
3-4 |
4-5 |
5-G |
||||
|
80 |
1-5 |
2-0 |
2-9 |
3-9 |
4-9 |
|||||
|
90 |
1-3 |
1-8 |
2-G |
3-5 |
4-4 |
|||||
|
100 |
1-2 |
1-G |
2-4 |
3-1 |
3-9 |
Thickness of belt— fa inch.
(Unwin.)
Modern Gas Engines.
Compression of charge = 89 to 90 Ibs. per square inch.
Initial pressure at moment of explosion = 300 Ibs. per square inch,
Consumption per effective horse-power = 16-48 cubic feet.
Actual efficiency = 28-26 per cent.
Mechanical efficiency = 86 per cent.
Fuel consumption per I.H.P. = 0-8 Ib. anthracite coal.
Gas Engines. — The consumption of gas is now under 16| cubic feet per horse-power. The governors of gas engines control the valve that admits gas to the cylinder. When the speed is low gas is admitted, and an explosion puts new energy into the flywheel ; when the speed is high, no gas is let in and no explosion takes place. Ignition is chiefly by means of a Bunsen flame in England, and by electric spark on the Continent.
In the " Otto " cycle gas engines the gas and air are drawn in by a forward motion of the piston, on the return stroke it is compressed, at the commencement of the next forward stroke it is ignited and the piston is moved forward, the return stroke expelling the products of combustion.
Modern gas engines of best type compress the charge to from 40 to 60 Ibs. per square inch before ignition.
GAS ENGINES. 191
Mean effective pressure in " Otto " cycle gas engines = 50 to GOlbs, per square inch.
Gas engines of 100 brake horse-power and upwards are now made to consume not more than 20 cubic feet of town gas per horse-power per hour at full load.
Experiments made show that the deleterious effect of burnt gases is much overrated in the case of coal gas products in gas engines. (F. Grover.)
Consumption per brake horse-power per hour at half load with gas or steam engines is about 40 per cent, more than at full load.
Gas Engines.
Cubic Feet Gas B. H. P. per B. H. P. Hour.
Simplex . . . 8-79 . . . 20-38
Atkinson Cycle . . 4-89 . . . 22-5
Forward . . . 4-8 . . . 23-97
Otto Crossley . . . 14-7 . . . 241
Atkinson's Differential 2-6 . . 25-7
Griffin .... 12-5 . . . 28-5
Clerk's Engine . . 7-2 . . . 30-4
Horse-power of Gas Engine. — The indicated horse-power is equal to the mean effective pressure in pounds per square inch multiplied by the length of the stroke in feet by the area of the piston in square inches and by the number of explosions per minute, and divided by 33,000.
Gas engine diagrams prove that the rise in pressure which takes place in the gas engine through the gas exploding at the dead point relatively slowly is not more rapid than that which occurs on the admission of high-pressure steam to the steam cylinder.
Mechanical efficiency of a gas engine, about 80 to 85 per cent.
Gas engines can be run to within 3 to 4 per cent, of the normal rate.
Temperature in cylinder of gas engines, 2,500° F. to 3,000° F.
The work expended in compressing gas does not increase pro- portionally with the pressure, but is relatively much less with high pressures.
Average gas, 1 to 8 to 12 of air in gas engine.
Only 2£ times the power is needed to increase a pressure of 10 atmospheres tenfold — i.e., to raise it to 100 atmospheres.
A good steam engine develops one I.H.P. per kilogramme coal of a calorific power of 8,500 calories.
A cubic metre of gas develops 5,300 calories, and one I.H.P. in a gas engine with a thermal duty of 50 per cent, in favour of the gas engine. (Hirsh.)
Exhaust pipes from gas engines should have easy bends.
At ordinary atmospheric pressure and temperature mixtures of gas and air will not ignite explosively, if at all, when the air amounts to about fourteen times the bulk of a given quantity of gas, and similarly the mixtures will not ignite explosively if too much gas be present,
192 GAS ENGINEER'S POCKET-BOOK.
One pound of a mixture of oxygen and coal gas in the proportions required for complete combustion would upon ignition develop about the same energy as 3J Ibs. of gunpowder.
With coal gas at 3-?. per 1,000 cubic feet and coal at 15s. per ton the gas engine consuming 20 feet per I.H.P. per hour = a steam engine consuming 9 Ibs. of coal per I. H.P.per hour. (T. L. Millar.)
With lighting gas the cost of running large gas engines is about t-ke same as for steam engines, lighting gas being much dearer than generator gas for power purposes, especially for engines above 12 H.P.
Gas consumption in Dessau tramcars worked by gas engines = 31 '2 cubic feet per mile run. including loss in compression, which is very little. (Herr von Oechelhauser.)
Gas Engines for Tramcars. — An 8 H.P. engine (Otto type) : charge of compressors = 8 miles supply, cost = Id. per mile for gas.
From 4 to 6 gallons water are required per I.H.P. to cool gas engine cylinders.
In cooling the cylinders of gas engines 35 per c^nt. of the thermal units in the gas are lost.
Capacity of circulating tanks should equal 23 to 30 gallons per I.H.P.
To Find Size of Dry Meter for Gas Engines.
Brake horse-power X 3-4 -f- 5 = number of lights. The size of supply pipe to engine can be found by reference to table of meter dimensions.
To Find Size of Exhaust Pipe.
From 1 to 5 brake horse-power, 1 inch to If inches diameter.
Above that size, diameter in inches = 0'528 X H.P.0'5".
The heat of exhaust pipes is great, and likely to burn wood if too near. Bends of 6 inches or more radius only should be used ; no elbows or tees. Turn the outlet of the pipe to look downwards.
To Prevent Excessive Noise in Exhaust Pipe.
The pipe can be carried into a drained pit and surrounded with stones, over which a covering of straw can be placed.
Quantity of Water Required for Cooling Cylinder,
About 5 gallons per I.H.P. per hour if taken direct from mains, and led to under side of jacket at clearance end of cylinder, and removed from upper side at the opposite end. If hard water is used, add a handful of washing soda to tank every month.
Circulating Tank's Capacity.
Twenty to 30 gallons per I.H.P. with pipes from 1 inch to 3 inches diameter, according to size of engine. The return pipe is usually a little larger than the flow, with a rise of at least 2 inches per foot leading to the tank at the normal water level.
GAS ENGINES.
193
Value of Explosive Mixtures. (Dugald Clerk.)
|
Mixture. |
Maximum Pressure |
||
|
of Explosion above Atmosphere in Ibs. per Square Inch. |
Time of Explosion. |
||
|
Gas. |
Air. |
||
|
1 vol. |
13 vols. |
52 |
0-28 second. |
|
1 „ |
11 „ |
63 |
0-18 „ |
|
1 „ |
9 „ |
69 |
0-13 „ |
|
1 „ |
7 „ |
89 |
0-07 „ |
|
1 ,, |
5 » |
96 |
0-05 „ |
Temperature before explosion, 64° F. Pressure before explosion, atmospheric.
Examine the ignition tube occasionally to see that no soot has been deposited by the Bunsen flame.
Before starting compress the gas bag and then turn on gas, turning the engine meanwhile to remove the air which may have accumulated in the gaspipes.
To stop the engine shut the gas-cock near cylinder — not at the meter.
The ratio of heat converted into work in a gas engine is greater than in a steam engine.
Average heat units lost in the jacket or cooling water, 35 per cent. „ ,, „ „ „ exhaust, 37 per cent.
Otto or Four-Cycle Gas Engines. — An explosion takes place every four strokes, or one per double revolution of the crank shaft, viz., piston advances, drawing in the explosive charge ; it then returns, compressing the mixture ; next ignition takes place, the piston is driven forward, and on retiring finally expels the waste products of combustion.
The consumption of ordinary illuminating gas in modern gas engines equals from 20 to 26 cubic feet per I.H.P. per hour for moderate to small powers, and for larger powers 18 to as low as 15 cubic feet has been obtained, and with the compound type as low as 10. This, if supplied with Dowson gas, means only *8 Ibs. of coal per I.H.P. per hour. The mechanical efficiency may be taken as from 80 to 85 per cent, at full power, and Irom 70 to 75 per cent, at half power.
Messrs. Crossley state that with town gas at 3*. per 1,000 the working cost of a gas engine of 14 horse-power nominal and up- wards is greater than that of a steam engine.
It has been proved that by scavenging the power of a gas engine can be increased 10 per cent., or the consumption of gas reduced, keeping the power the same.
With coal gas it is a moot point if the products of combustion hurt the next charge in gas engines.
Gas engines are most economical at full power.
G.E. O
194
GAS ENGINEER'S POCKET-BOOK.
A speed test made with a Moscrop recorder on a single-cylinder double-acting " Kilmarnock " Otto cycle engine showed a variation of 2| per cent, at powers varying from normal full load down to one third.
Value of Coal Gas of Different Candle Powers for Motive Power. (C. Hunt.)
|
Candle Power. |
Consumption Cubic Feet per I.H.P. |
Relative Value for Motive Power. |
Relative Value for Lighting. |
|
11-96 |
30-31 |
1-000 |
i-ooo |
|
15-00 |
24-41 |
1-241 |
1-254 |
|
17-20 |
22-70 |
1-335 |
1-438 |
|
22-85 |
17-73 |
1-709 |
1-910 |
|
26-00 |
16-26 |
1-864 |
2-173 |
|
29-14 |
15-00 |
2-020 |
2-436 |
Oil Engines,
The oil consumed per hour equals from -7 Ib. with American oil to *86 Ib. with Russian per indicated horse-power.
A Priestman oil engine, using oil above 75° F. flashing point, developed 1 brake horse-power per 1-25 Ib. oil. (W. Anderson.)
In a Priestman oil engine tested by Professor Unwin —
•69 and -86 Ib. oil used per I.H.P.
•84 „ -94 „ „ „ B.H.P.
Thermal efficiency 1331 per cent. Loss of heat in cooling water 47-54 per cent. Mechanical efficiency 82 to 91 per cent. Loss of heat in exhaust gases 26-72 per cent.
To find Leaks in connections under Suction.
By fixing a small governor on the byepass of the exhauster, weighted to 2 inches, a pressure will be thrown on the plant up to the hydraulic, any leaks showing themselves and explosions prevented.
SCRUBBERS AXD WASHERS. 195
SCRUBBERS AND WASHERS.
Herr Reissner's Rule. — 5 cubic feet to 6 cubic feet per 1,000 cubic feet per 24 hours of scrubbers.
Wyatt's Rule. — 100 cubic feet internal capacity of vessels (scrubbers and washers) with a gas contact of from 15 to 27 minutes per ton per diem. Gas in scrubbers should equal 1 per cent, of the maximum daily make to give requisite contact time.
Horizontal net sectional area of all the scrubbers is 2 square feet per ton per day maximum make.
Capacity of scrubbers should be 15 cubic feet per 1,000 feet of gas per diem, the vessel being one third the diameter of its height. (Richards.)
Another Rule. — Scrubbers should be equal to allowing a contact for 10 to 15 minutes of greatest make. Height is an advantage, so that the gas may be easier broken up and wetted surfaces presented.
Tower scrubbers usually 6 or 7 times the diameter high.
Scrubbers should be cylindrical. Height equal to 6 or 7 times the diameter. Capacity equal to 9 cubic feet per 1,000 cubic feet per diem maximum make. (Herring.)
Newbigging's Rule for tower scrubbers, 9 cubic feet per 1,000 cubic feet gas made per day.
The washer or scrubber wherein the gas is broken up into small streams passing in contact with wetted surfaces is preferable to that in which the water is divided into small drops and which fall through the gas, as the bulk of the gas is at least 100 times, and more often 1,000 times, that of the liquid.
A good scrubber should so distribute the water or liquor that the whole of the surfaces exposed to the gas in its passage should be evenly wetted, with length of contact and such contact ensured.
The use of a washer requiring a separate engine must be compared with the extra cost of the fuel required, in one throwing some 3 or 4 inches pressure upon the exhauster.
Scrubbers filled with coke will collect tar and cause a lowering of illuminating power by absorption of light-giving hydrocarbons.
When coke is used in a tower scrubber a space of 6 inches is usually left above each layer before the next tier of sieves.
Average Surface presented to Gas in Scrubbers.
When filled with coke . . . '3 or 8£ sq. feet per cubic fo^t.
., ., 3-inch drain pipes *54 „ 17 „ „ „
» » 2 „ „ ,, '66 „ 21 „ „ „
„ boards . . TOO „ 31 „ „
Scrubber Boards should be | inch thick with f inch or £ inch space between.
Boards 11 inches deep, | inch thick, set f inch apart, are used in tower scrubbers with success.
02
196 GAS ENGINEER'S POCKET-BOOK.
Ten volumes of water at 60° F. and 30 inches pressure absorb—
7,800 volumes ammonia. 25-3 , sulphuretted hydrogen.
10-0 1-25 •37 •156 •156 •156 •160
carbonic acid.
olefiant gas and probably other hydrocarbons.
oxygen.
carbonic oxide.
nitrogen.
hydrogen.
light carburetted hydrogen.
When water has been saturated with one gas and is exposed to the influence of a second it usually allows part of the first absorbed to escape, while an equivalent quantity of the second takes its place.
Thus a large volume of an easily soluble gas can be expelled by a small quantity of a difficultly soluble one. (Dr. Frankland.)
Liquor distributers sometimes fixed half way up scrubbers where only one scrubber is in use.
The whole of the ammonia can be removed from the gas in practical working by using 3 gallons water per ton of coal carbonised, and the quantity of NH3 per 1,000 cubic feet need not exceed '3 to 4 grains at the outlet of the clean scrubber.
Quantity of water required in tower scrubbers from 10 to 18 gallons per 10,000 cubic feet gas made.
When more than one washer is used the liquor should be made to flow from the one the gas enters last through to the first, so that the gas meets the stronger liquor first.
Provide byepasses to all the different parts of the works.
Washers.
About 28 gallons of liquor of 10 oz. strength can be obtained from 1 ton Newcastle coal.
lleaction of cyanides (Prussian blue) : —
H4CN + FeS04 = (NHJ4Fe(CN)8 + (NH,)2SO, 3NH4Fe(CN)6 + 2Fe2Cl6 = 3Fe"Cy2,2Fe'"aCy6 orFe7Cyia + 12AmCl.
Pressure thrown by washers varies from 1 to 4 inches.
PURIFIEES. 197
PTJEIFIEES.
In fixing upon size of purifiers note should be taken of the quality of coal likely to be used for manufncturing gas. Some Midland coals produce gas containing nearly double the amount of H2S which is to be found in Newcastle coal. Have the purifiers large enough is an excellent rule.
Scotch coals produce large quantities C02.
Clegg's Rule for Area of Purifiers. — 1 foot area per 3,600 cubic feet, maximum make, per diem.
Hughe*7 Eule for Area of Purifiers. — 1 square yard sieve per 1,000 cubic feet, maximum make, per diem.
Newbigging's Eule for Area of Purifiers.
Maximum daily make x 6
— — - = square feet area each purifier.
Newbigging's Eule for Area of Purifiers Connections.
Inches, diameter =x/area of purifiers in. feet
For large purifiers deduct one-eighth.
Beckton practice : 1 square foot of purifier area per 2,500 cubic feet made per diem.
Allow, say, 1 square yard of active grid per 1,000 feet of gas.
Sulphur purification requires for 2,000,000 plant 8 boxes 32 feet x 32 feet x 6 feet deep, with 4 trays for lime and 3 for oxide. (A. Colson.)
Purifying shed for above, 320 feet x 60 feet. (A. Colson.)
Rate of passage of gas through lime purifiers should not exceed 2,000 cubic feet per foot of surface per 24 hours. (Gr. Anderson.)
Purifiers (where lime only is used and no sulphur clauses) should allow a contact of 15 minutes of greatest make, or cubical contents = | hour's make, with 5 tiers lime, each 2£ inches thick.
C. Hunt's Eule for Area of Each Purifier" in a series is not less than 0-1 square foot for every ^ per cent, by volume of the maximum quantity of C02 experienced. C02 varies from 1^ to over 3 per cent.
Lime and oxide purifiers when worked in conjunction require from 20 to 30 square feet per ton. (C. Hunt.)
G. C. Trewby's Eule.— 320 feet for each vessel per 1,000,000 cubic feet of daily manufacture.
Four feet area per box per ton of coal carbonised per day with 6 purifiers in the series, 4 for lime and 2 (catch) for oxide. (F. Livesey.)
Wyatt's Eule.— 100 superficial feet of sieves per ton per day 1,620 cubic feet to house the purifiers with a floor area of 50 square feet per ton per diem, 133 cubic feet total capacity of vessels, gas contact of 15 to 27 minutes, area of covers of purifiers 3 square feet per ton per diem.
198
GAS ENGINEER'S POCKET-BOOK,
Lime and oxide sheds : 810 cubic feet of building structure floors area of 25 square feet per ton per diem.
Wyatt's Rule.— 33 cubic feet or 50 superficial feet per ton per day, contact time 5 to 8 minutes.
The useful surface for passage of gas should be |rd the volume of the oxide, time of contact 48 seconds, bulk should equal J^t-h of the gas passed per hour, with 1 layer 24 inches thick ; material showed - 15-65 per cent, total sulphur and 11-75 per cent, free sulphur, while with 4 layers each 6 inches thick it showed 14*96 and 9'03 per cent, respectively. (Messrs. Delseaux and Renard.)
In the Beckton method of 8 purifiers an area of 0'4 foot per 1,000 cubic feet of gas per vessel is sufficient. (L. T. Wright.)
Allow half a square foot per 1,000 cubic feet maximum daily make for area of each purifier. (Herring.)
Purifying surface may range from 1*3 to 4 square feet per 1,000 cubic feet gas per day.
Area of each purifier should equal 676 square feet per million per day.
Speed of gas through purifiers should be as slow as possible.
Herr Reissner's Rule. — Purifiers. Five trays with oxide in each, 1-17 square feet area per-1,000 cubic feet in 24 hours if 4 purifiers, all included in above. Catch purifier with 4 to 6 trays sawdust.
Use purifiers of large area : with lime, 2 to 4 tiers of sieves with layer of lime 6 to 9 inches thick ; with oxide, 2 or 3 tiers of sieves with layer of oxide 18 inches deep on each.
Purifiers (construction notes). — Thickness of cast iron purifier plates should never be less than | inch. The usual width of same 5 feet. Flanges of bottom plates should be 2f inches x f inch over and above the thickness of plate.
Strong and deep brackets should be fixed under lute, as strain is greatest at this point. (F. S. Cripps.)
Cast iron plates for purifiers, if made larger than 5 feet by 5 feet, are liable to twist in casting. Flanges should not be less than 3 inches deep, and thickness about \ inch to \ inch ; plates \ inch thinner.
Depth of water lute in purifiers varies from 12 inches in small purifiers to 30 inches in larger ones \ width from 4£ inches to 8 inches.
Seals of purifiers should never be less than 18 inches deep.
Diameter in inches of pipes in connections to purifiers should equal the square root of area of purifiers in feet.
Arrangements of Purifier Connections. (Dempster.)
PUBIFIER CONNECTIONS. 199
Arrangements of Purifier Connections. (Dempster)— continued.
|
1X1 |
1X1 |
||||||||
|
o- |
o- |
O |
° |
||||||
|
1 |
c |
g |
E |
3 |
E |
3 |
|||
|
-31 |
3 |
51 |
I |
? |
51 |
1 |
1 |
•a , 9 |
|
200 GAS ENGINEER'S POCKET-BOOK.
Arrangements of Purifier Connections. (Dempster)— continued.
|
to |
V A |
Ql |
E |
1 |
Ql |
||
|
T |
0 |
|
f~ |
J |
1 |
* |
i |
t |
||||||
|
6 |
6 |
6 |
6 |
||||||||
|
E |
^h |
----6 |
E |
3 |
E |
|
-H- |
-.4 |
|||
|
a o-- |
L-H- 1 |
'SI o- |
-B- ( |
c |
51 0- |
-N- 1 |
51 o- |
-B- t |
si |
||
|
* |
ft |
i |
a |
J |
Flanges of purifier plates should be planed (not necessarily the whole width, a strip f inch or f inch wide each side and at ends being sufficient), a layer of vulcan cement or red and white lead being put into the joint before it is bolted up. The alternative method is to nave a fillet cast on inside of flange and the joint caulked with iron borings and sal-ammoniac and sulphur.
It is usual to keep purifiers and gasholders away from retort houses to avoid chances of lighting up at escapes or explosions.
Fastenings to purifiers should be strong enough to resist pressure, equal to a column of water the height of the depth of lute, upon the whole area of the cover, the weight of cover causing the gas to blow the water from the lute.
CLAUS PROCESS. 201
Valves or ground plugs should be provided for permitting the air ' to enter while the cover is lifted, and should at least equal one-third the diameter of the connections to the purifiers.
Side sheets of purifier covers should be made thicker than the top sheets, as the level of the surface of the water is where the plates will first rust.
Crown sheets may be of No. 12 Birmingham wire gauge.
Purifiers in the open can be kept warm in winter by the use of hay or straw, and cool in summer by spraying water over the covers.
If the top of the purifiers are kept 18 inches above ground the material can be easily removed and wheeled in.
Lifting of purifiers is best done by straps at the sides of the covers.
Purifier sieves usually made 2 inches thick with f-inch taper deal bars, and distance blocks, oak side strips 1£ inch by 2 inches, and fastened by f-inch bolts or rivets.
Usual thickness of layers. — Oxide, 2 feet 6 inches deep ; lime, 1 foot deep.
About TOlbs. quicklime will remove C02 per 1 ton coal.
Oxide heated to 70° C. revivifies easier.
Lime should be sulphided below 40° F.
135 gallons water required per cubic yard dry lime, making 2£ yards slaked material.
One cubic yard kiln lime weighs 11 cwts.
Mr. W. King has erected a purifier house without valves — U tubes, which can be filled with water to prevent the passage of the gas, being used.
The Claus Ammonia Process of Purification. — The gas, having passed through a tar extractor, is then passed through several scrubbers filled with broken ganister bricks, and here meets ammonia gas, and in the first two scrubbers ammoniacal liquor freed from C02 and H2S, the gas being entirely freed in its passage from C02 and H2S, while of ammonia there remains at the outlet of the last scrubber only the usual faint traces, and the bisulphide of carbon is reduced by from 20 to 70 per cent. Arrangements are made that in 5 towers the scrubber liquor is heated to a carefully regulated temperature for the purpose of driving off the C02 and H2S with as little loss as possible of ammonia. It is then passed through 3 more towers, in the second of which it is exposed to free steam, which deprives it of all traces of C02 and H2S, and also of all ammonia, except what may be present as fixed in the form of sulphocyanide of ammonium ; in the third tower the hot vapours (187°) are condensed to 120° or less, and are then ready for use again to remove the impurities. All the sulphur gases driven off from the liquor are deposited in a chamber in the form of pure sulphur, equal to from 10 Ibs. to 141bs. per ton of coal used.
202 GAS ENGINEER'S POCKET-BOOK.
GASHOLDER TANKS.
As a general rule the bearing capacity of ground 30 or 40 feet below the surface is greater than at the surface itself, but in all cases bore- holes should be made to see that the solid ground upon which it is proposed to lay the bottom of the tank is fairly level, and that it is of sufficient depth. In some cases the strata of, say, ballast, which would safely carry the tank walls, &c.. have been cut through, or nearly sn, and when the tank has been completed the level of the walls has varied considerably.
The larger the number of the borings taken around a proposed gas- holder tank site the better to ensure that the foundation is level and equally weight-resisting.
If any doubts exist as to the solidity of the ground where the tank is proposed to be placed it is better to put up an iron or steel one, which may be made to rest on piles and cross timbers.
It is often better to raise the level of the wall of the tank when water is found in the subsoil which may afterwards injure the nature of the foundation.
For tanks up to 36 feet deep and inside diameters of 150 feet : j^th the depth of tank = thickness of concrete walls. |th „ „ = „ piers.
£th „ „ = width of piers.
(Wyatt, 30th April, 1889.)
The well or sump which is sunk before commencing a tank may be lined with steining (open brickwork without mortar), or merely timbered with stout timbers if it is proposed to fill up the sump when the tank is completed. In some cases large pipes (cast iron) have been let in as the excavation proceeded, without jointing, and thus formed an excellent backing to prevent the sides falling in.
The sump should be at least 3 to 5 feet deeper than the lowest part of the excavation to be made for the tank ; often a considerable amount deeper will lessen the after expense with tanks in bad ground.
Sometimes more than one sump is found necessary, or drain pipes have to be laid to convey the water to the pumps, which should always be in duplicate.
Natural Slopes of Earths with the Horizontal Line or Angles of Repose.
|
. . 40 degi |
•ees or T2 to 1 or 1-30 to 1 or 0-27 to 1 or 1-89 to 1 or 0-7 to 1 or 1-25 to 1 or 1-0 to 1 or 1-0 to 1 or 3-3 to 1 or 1-89 to 1 |
|
|
. 38 , |
||
|
. . 22 , |
||
|
Vegetable earth average Compact earth average . |
; . .28 . . 50 i . 39 |
|
|
Rubble average . 0 Clay, well dried, average |
. . 45 . 45 , 16 |
|
|
. 28 |
GASHOLDER TANKS. 203
General Tank Notes,
An Iron or Steel Tank saves excavation and expenditure on foundations in many cases.
Steel tanks should be well grouted in, in many places, when lowered on to their bed.
Steel tanks require more maintenance than stone or brick ones, and more steam for preventing freezing of the water during frosty weather.
Cost of a steel tank usually one-half to two-thirds that of an excavated brick or concrete one.
Cost of steel tanks about 3'3d. to 3'7tf. per cubic foot capacity.
Cost of brickwork tanks about -i'M. to o'(Jd. per cubic foot capacity.
The plates in the bottom row of a 50 feet deep X 190 feet diameter tank have been made If inch thick X 4 feet 4 inches wide X 24 feet 9 inches long.
It is usual to put the flanges of cast iron tank bottom plates inside and the flanges of the side plates outside.
Tanks may with advantage be left large enough to allow of an extra lift when being first designed and laid out, although it may not be at the moment required.
The larger the volume of water in a tank the less the liability to freeze.
Thickness of Tank Walls at any point in inches =
Pressure of water (pounds per square inch) X radius of tank in inches Cohesive force of wall in pounds per square inch - pressure of water.
Force of water tending to burst a tank outwards = 62'5 X diameter of tank X g (depth).
Pressure on wall of tank due to earth backing therefore equals resistance of earth X outside diameter of tank X \ (depth2).
Resistance of the weight of wall equals half the cubic contents of the wall in feet X weight of 1 cubic foot of the wall.
Resistance of the cohesion of the material of the wall equals cohesive force X height2 x average thickness of wall.
Cohesive force of bricks in cement 1 (cement to 3 sand) equal to 31,080 Ibs. per square foot.
Resistance of earth backing dry equal to \ an equal column of water. (Sir B. Baker.)
Resistance of earth backing, water-logged, equal to 1J an equal column of water. (Sir B. Baker.)
Resistance of earth backing, clay or earth, equal to 1,200 Ibs. per square foot. (Newbigging.)
204
GAS ENGINEER'S POCKET-BOOK.
Ultimate Resistance of Loam Earth per Square Foot in Ibs. E. A. Tests.
|
Mean Depth of Anchorage below |
Inclination of Force drawing the Anchorage (in a Direction perpendicular to its Face). |
||||
|
Surface. |
Vertical. |
j |
1 |
} |
* |
|
1 foot |
808 |
933 |
1,244 |
1,300 |
1,430 |
|
1 foot 6 inches , .' |
1,040 |
1,458 |
2,100 |
2,180 |
2,360 |
|
2 feet |
1,925 |
2,700 |
3,880 |
4,032 |
4,370 |
|
3 feet .... |
3,024 |
4,400 |
5.860 |
6,160 |
6,750 |
|
4 feet |
5,470 |
8,000 |
10,660 |
11.200 |
12,260 |
|
5 feet .... |
14,112 |
22,000 |
29,330 |
30,800 |
33,730 |
In clamp sand the resistance would be half that in earth. A factor of safety in tank walls of 3 is ample.
Besistance of Different Earths to Horizontal Compression, (M. Arson.)
Sand 2,050 Ibs. per square foot.
White tufa (a light stony powder) 1,640 „ ., „ „
Vegetable earth mixed with gravel 900 „ „ „ „
The earths were well watered and punned.
The Backing to Gasholder Tank Walls should be well punned and watered to cause it to have direct pressure upon the wall, as cracks are almost invariably found in a vertical direction and only open a very slight distance, which would suggest that the walls have then taken up the support of the backing.
Clay has often been known to" sustain a pressure of water of 15 Ibs. per square inch, or about 1 ton per square foot.
One cubic yard* puddle weighs about 2 tons.
Puddle may be thrown from a height of 20 feet with advantage, but should not be laid in layers of more than 10 inches at a time.
Where clay is to be found upon the site it will probably be cheaper to construct a puddle tank than a rendered one.
Puddle. — Work the clay well up with water to break up the original formation, and bring about a new arrangement of the particles, adding sufficient water to fill up every pore.
If possible, expose the clay before tempering for a considerable time to the air. It should be opaque, not crystallised, with a dull earthy fracture, and exhale an argillaceous smell.
Tenacity and power to retain water is the principal requirement. If a roll well worked up by hand to eight or ten times its thickness be suspended, while wet, by one end it should not break. It should retain its original quantity of water when formed into a basin and filled for 24 hours, if covered up to prevent evaporation. (W. Gallon.)
Puddle should be put in in layers of not more than one foot, and should be thrown in with force to cause it to adhere to that already in. The top of the puddle should be carefully covered when any dirt is being put in to form a backing, as any grit in the puddle may cause a leak, owing to the grit preventing a thorough adherence of the two layers of puddle.
TANK WALLS. 205
Puddle should be laid over the whole of the surface of the dumpling and connected all round to that under and on the outside of the wall without any break.
Brick tanks with f inch cement (neat), in two coats, can be made without puddle, and will prove quite tight.
Should a leak show itself when the pumping has stopped for testing the soundness of the tanks stock-ramming may be employed to fill up the space where the leak occurs. In doing this a hole is first cut in the wall or floor of the tank and a pipe inserted down to the puddle level, and then cartridges of clay are put in the pipe and forced down with rammers. These latter are frequently made with the heads so that several men can use their strength to ram the clay well into the hole.
In puddled tanks the pressure of the water is thrown upon the puddle and earth backing, and not upon the wall itself, while with a cement-rendered tank the pressure is upon the wall.
Hoop iron or thicker wrought iron bands are often imbedded in the cement of a tank wall, and considerably add to the strength. They should be bent round and turned back at the ends, and laid so that they hook one into the other and form a continuous band.
Where no backing is used to help Tank Sides to resist the pressure of Water the thickness of the Cylinder may be calculated as follows : —
When the thickness is less than s^th the radius the thickness = Pressure in Ibs. per square inch
— — - ., . * : — - X radius in inches.
bafe strength in Ibs. per square inch
This regards the material as only subjected to tensile strain. To find the Thickness at base of Wall to resist the overturning with the pressure of quiet water level with its top and no backing (wall with vertical back and sloping face) : — Thickness of base at foot =
\/(H£2i't. x factor of safety*) -f (batter2 ft. x sp. gr. of wall) 3 X sp. gr. of wall. Required moment of stability of wall •Factor of safety = - Ovet.tuming momcnt o£ ;ater<
Where cylindrical hoops are placed around tanks, to find the distance apart at which they should be fixed to each to sustain the same strain —
Fix upon the number of straps required then for the first, N/l X total No. of straps X depth of tank
Total No. of straps
= Distance from top of tank for 1st strap. For the second strap, ^2 x total No. of straps X depth of tank
Total No. of straps. = Distance from top of tank for 2nd strap.
And so on for each strap, substituting for the 1 and 2 in above formulae the number of the strap from the top.
.
_- -
3M
_T -
-
~~ .
~
_ _
_ _ '
:
_
' _'
_ '
x r
-
-
208
GAS ENGINEER'S POCKET-BOOK.
Thickness of Sheets of Wrought Iron for Tanks of Different Diameters and Depths,
Factor of safety, |th. Deduction for rivet holes, 40 per cent.
CONCRETE TANK WALLS. 209
When the first batch of concrete is mixed, the quantity of water per bushel of dry materials should be noted, and the same propor- tions held to with the other batches, uniformity in this respect being of the utmost importance. As much water should be added as will give a mixture that allows a man treading over it to sink in to a depth of at least 6 inches. No stones used for concrete should be larger than will pass through a mesh 2 inches square. Concrete should not be dropped or made to slide down a shoot, and inferen- tially it should be laid with a spade without a fall of any kind, and then it requires to be trodden down.
Stout bars of flat iron laid into the walls of a concrete tank, and hooked together to form a complete ring on edge are said to give great strength to the same. The expansion of iron and cement con- crete being nearly equal prevents fracture between the two materials.
Firebrick rubbish and furnace clinkers form with sand or sharp grit excellent material for concrete.
Concrete composed of 1 part cement to 10 or 12 coke breeze is porous.
A good coat of asphalt will render a tank quite water-tight.
A coating of hot asphalt and tar is also used to render cement tanks water-tight.
Rendering is usually done with equal parts Portland cement and sand, and laid on from £ inch to f inch thick, with a final layer of neat cement carefully trowelled on about | inch thick.
French engineers usually specify a much greater thickness of cement and sand in equal parts, without the neat cement layer.
Portland cement rendering usually made of 1 cement to 3 of well washed sand.
External mouldings and linings to water tanks neat cement.
A simple Rule to avoid loss in Cupping is, when constructing, to make the tank measured from the rest-stones the full depth of the various lifts, plus a depth equal to the difference between the dis- placement of the inner and outer lifts, and add a margin of 3 inches.
Pumps for gasholders should be made with an outer casing to the bottom of the pipes to be pumped, so that the pump may be removed for repairs without an escape of gas.
Tank, 114 feet x 31 feet deep, at Wellingborough, made with Portland cement concrete 7 to 1, and puddled at back, no rendering, concrete over dumpling (of clay) 6 inches thick.
Wall of tank 123 feet diameter x 30 feet deep = 3 feet G inches thick at bottom to 2 feet thick at top.
A cast iron tank 112 feet diameter X 25 feet deep has been erected, weighing about 500 tons.
Concrete made with clinkers and broken firebricks and retorts said to be stronger in tension than if made all Thames ballast.
1210 GAS ENGINEER'S POCKET-BOOK.
GASHOLDERS.
General Notes.
Mr. Gr. Livesey stated (1882) that 201. per 1,000 cubic foot capacity was a usual cost of gasholders of moderate size.
Two holders of about equal size should be provided in all works.
When extending, holder capacity should be doubled by the addition of one holder of equal capacity to all the previous ones combined.
Single lift holders should not be usea except for less than 10,000 cubic feet capacity.
Height of lift should = —
Holders above 500,000 cubic feet capacity should be three lifts.
When weight is required to give necessary pressure increase the thickness of sheets and cups.
No necessity to break joint in side sheets, as load is much below the strength of the sheets.
It should be borne in mind that 'the larger the sheets the less rivets are required, and the liability to leakage is reduced.
The strain on top sheets diminishes in exact proportion to the rise, and is uniform throughout the top sheets.
Usual rise = ' 2Q — . Shapefof dome equals segment of a sphere. With rise = diameter, No. 11 Birmingham wire gauge sheets arc
sufficient up to, say, 175 feet diameter, but when larger, No. 10 sheets and an increased rise would be better. Rivets ^ inches diameter.
The crown curb in trussed holders has not much work to do.
The best form of curb is an angle iron or steel, but in larger holders where the compressing strain may equal 200 tons other pattern curbs must be adopted.
Mr. Livesey considers 40 Ibs. per foot as the maximum wind force likely to be exerted on a gasholder ; and 57 per cent, of this force is exerted on the cylinder as compared with a flat surface.
When diagonal bracing of sufficient strength is in use, the side strength of the columns or posts need not be great as the strain is resisted by the bracing.
For moderate sized gasholders. Mr. G. Livesey and Mr. C. Hunt prefer cast iron columns.
Theoretically if pressure is brought upon a cylinder it tends to expand it in all directions.
In a gasholder at New Jersey, U.S.A., which overturned in a gale, all the columns but one fell outwards.
Mr. Foulis considers 50 Ibs. per square foot should be allowed for as wind pressure on gasholders.
Mr. Cripps suggests gussets to connect the first row of top sheets With the top row of side sheets in small holders.
NOTES ON GASHOLDERS. 211
To find the strain on top sheets — •
18-3 Weignt of side sheets in tons _ strajn
angle of top in degrees or,
(Half diameter of holder2 -f- rise2) X effective pressure of
gas X diameter of holder in feet ^^ n
8 X rise
It is essential that gasholders should be maintained perfectly level.
The Old Kent Road type of gasholder "is one of that class of structures in which it is impossible to foresee the exact intensity and nature of the stresses." (Sir B. Baker.)
Steel curbs are better than iron as they stand a higher compressivc strain.
Two angles, one set at each end of the first and thicker row of top sheets, is the easiest and simplest method of constructing a curb where considerable strain has to be resisted, as each inch of section is profitably utilised.
Radial rollers spread the wind pressure on one quarter of the guides.
Tangential rollers spread the wind pressure on one half of the guides.
The two combined spread the wind pressure on three quarters of the guides.
Mr. Webber considers the two combined spread the wind pressure on two-thirds of the guides.
With tangential, or these combined with radial rollers, the pressure from the curb is better distributed, and the strain upon the guides is thrown in a tangential direction, thereby bringing the diagonal bracing directly into use in the position it is best able to resist the strain.
Stays to inner lifts of gasholders are usually made of T iron trussed, but in large holders channel and H iron frequently take the place of the T.
Channel iron forms, on the outer lifts, both a stay and also a guide path for the next inner lift roller.
Vertical stiff en ers require securely fastening to cups and grips.
Vertical ro\ys of thicker section' plate are not advisable, as the riveting to the next rows on either side is not so tight.
Sometimes the stiffeners are riveted to the side sheets by rivets at very close pitch, sometimes at 1 foot apart, and at others only attached to cup and grip.
Gasholder sheets should never be allowed to oxidise, but receive a coat of boiled oil immediately they are planished and punched.
An average gasholder contains more than 40 feet run of riveting and joint per 100 cubic feet.
It is not considered advisable to rivet crown sheets to trussing in holders, as it prevents the sheeting ballooning out into a spherical shape, and throws great strain, on the rivets.
212
GAS ENGINEERS TOCKET-BUOK.
Weight of bell of holder is almost equal to that of the guide framing in wrought iron or steel.
All rivets should be well brought up with the set, firmly held and properly riveted, if a sound job is to be secured.
All holders should be well painted every year.
Wyatt says about 20 Ibs. weight of wrought iron is used per superficial foot of sheeting (inclusive of the guide framing). Of this 12 Ibs. is the holder proper and 8 Ibs. the framing. (October, 1887.)
Side sheets vary in thickness from No. 11 in large holders to 17 Birmingham wrire gauge in small ones.
The depth of each lift must never be less than ith of the diameter of the holder ; and it will work better if it be \th or ith the diameter.
With holders up to 120 feet diameter, it is cheaper to put in a light trussing than to place a wooden framing in the tank ; but above this size it is more economical to put a timber framing to receive the holder when down. The trussing of a gasholder should never be more than 10 to 12 per cent, of the floating weight.
Useless weight due to trussing of holders may cause an increase of 10 to 12 per cent, in the fuel account of the boiler supplying steam to the exhauster engine.
Large single lift gasholders are often made so light that weights are required to cause them to throw sufficient pressure. In this case water troughs should be employed so that the water can be run in at night when pressure is required, and the back pressure iu works relieved during the day in running off the water.
Mr. C. Hunt prefers cast iron columns for holders of moderate size, as a cast iron column is cheap and easy to construct.
It has been proposed to carry the pipe from the meter to the governor house, and there connect it by a valve to the town mains before leading it to the gasholders, so that in case of a stoppage at the gasholders it can be at once turned on direct into the town, a governor being used to give warning of the necessity of turning on the valve.
inches pitch.
Rivets Required to Join Different Thickness Plates in Gasholder Construction. (C. and W. Walker.)
| inch to -J inch require £ inch rivets at
I „ „ I „ „ t
2j „ 2 „
H »
1 inch lj[ inches If „ li »
i „ „ 10 B.W.G. „ 10 B.W.G. „ 10 B.W.G. „ 10 B.W.G.., & inch „ ij inch » ^ » »
13 " " ? " "
i
Riveting (single) to No. 11 plates
„ (double) „ „ = t
„ (single) f inch plates 1£ inch pitch = ith „ (double) „ „ „ „ = ith
=sVh weight of plates.
STRAINS ON CROWNS.
213
Eiveting to irons 2£ inches to 6 inches pitch average £th of weight of plates.
Not possible to join a thin plate to a thick one and make a gas- tight joint, therefore the second plate from curb should be half way between outer plate and crown sheeting in thickness.
Reduce the thickness of sheets gradually to ensure tightness.
Always rivet a thin sheet to a thick one. Allowance for lap of plates —
When the lap equals 1£ inches add ^ inch or 7 per cent, (no rivets).
Allowance for waste on rivets, 10 per cent.
„ for rivets, bolts, and laps over and above plates £ to £.
Expansion of cast iron 100 feet long = £ inch for 100° F. (Horton.) „ wrought iron „ „ „ =T% „ „ 100° F. copper „ „ „ =1-28,, „ 100° F.
Iron expands with tension and contracts with compression of its length per ton per square inch.
Table showing the Strains on a Holder 200 feet diameter, with Different Rises of Crown, (V. Wyatt.)
|
Rise of Crown of Holder in Feet. |
Surface of Domeequals <5"2S32 R. V. SquareFeet. |
Ratios of Dome to Plane Sur- face Area. |
Radius of Dome. |
Tension on ^ of Dome. |
Tension on 1 Foot in Length of Dome. |
Compres- sion on One Sec- tion of Top Curb. |
|
0 |
31416 |
1-0000 |
0 |
|||
|
10 |
31730 |
1-0100 |
505 |
528 |
3-40 |
331 |
|
15 |
32091 |
1-0214 |
340 |
348 |
2-20 |
213 |
|
20 |
32672 |
1-0400 |
260 |
272 |
1-80 |
161 |
|
25 |
33300 |
1-0600 |
212 |
222 |
1-40 |
126 |
|
40 |
36442 |
1-1600 |
145 |
151 |
0-96 |
70 |
|
50 |
39250 |
1-2500 |
125 |
131 |
0-83 |
51 |
|
100 |
62832 |
2-0000 |
100 |
104£ |
0-67 |
00 |
Doubling the rise of the crown reduces the strain on the top sheeting one half ; here it is well to break joints as strength is required, and 96 per cent of the plates can be ordinary square sheets. Strain being equal on all crown sheets, they should be of equal thickness.
Radiating strips are unnecessary. Usual rise of crown = —
in the form of a segment of a sphere, in this case No. 11 gauge sheets are sufficient for gasholders of moderate size, but for 200 feet diameter holders No. 10 gauge sheets bettor and larger rise. Rivets in crown sheets should be & inch diameter.
Trussed holders require only moderate curbs.
Cheapest (and easiest and simplest to construct) curl), is two angles of iron or steel, one at each end of a flat plate.
214 GAS ENGINEER'S POCKET-BOOK.
Messrs. C. and W. Walker construct all their holders to one curve for the top, which is an arc of a circle 405 feet radius, but for holders 1 under 50 feet diameter give them a greater rise than this.
Strain on crown sheeting varies almost inversely as the rise.
Rise of crown sometimes made *875 of an inch per foot in diameter, which is the form it would take with a bursting pressure.
It has been suggested that a radius of 400 feet for gasholder crowns should be used, as £ inch sheets are then strained to what they will safely bear in most gasholders.
Pressure of snow may cause. a load of 51bs. per square foot over £th the area of a holder, and the centre of gravity may be (say) £th diameter from edge. (F. S. Cripps.)
1 cubic foot fresh snow 5 to 121bs. . . Trautwine.
1 „ „ snow compacted by rain 15 to 501bs. „
Weight of gasholder bell equals weight of 1 cubic foot water X area on water line in feet X pressure thrown in feet, or,
Area X 5-2083 = Ibs. per inch pressure.
Equilibration chains to gasholders.
Formula for required weight of chains :
iv = weight of 1 foot vertical of gasholder in Ibs. G = specific gravity of iron in ditto. W = weight of 1 foot of chain in Ibs. N = number of chains.
W =
2 ON
To find the weight of a gasholder —
W = weight in Ibs. A = area of water surface in sq. ft. p = pressure in inches thrown, then, W = A
To find pressure of a gasholder : —
W = weight in tons. d = diameter in feet. $ = pressure in inches.
547 W
FORCE OF THE WIND,
215
Force of the Wind.
|
Velocity. |
Force. |
||
|
Miles per Hour. |
Feet per „ Second. |
Lbs. per Square Foot. |
|
|
1 |
1-47 |
•005 |
Hardly perceptible. |
|
2 |
2-93 |
•012 |
|
|
3 |
4-40 |
•044 |
Just perceptible. |
|
4 |
5-87 |
•048 |
|
|
5 |
7-33 |
•123 |
Gentle pleasant breeze. |
|
10-0 |
•229 |
||
|
10 |
14-67 |
•300 |
Pleasant brisk gale. |
|
20-0 |
•915 |
||
|
15 |
22-0 |
1-107 |
|
|
20 |
29-34 |
1-968 |
|
|
30-0 |
2-059 |
||
|
25 |
36-67 |
3-075 |
Very brisk gale. |
|
40-0 |
8-660 |
||
|
30 |
44-01 |
4-429 |
|
|
50-0 |
5-718 |
||
|
35 |
51-34 |
6-027 |
High winds. |
|
40 |
58-68 |
7-873 |
|
|
60-0 |
8-234 |
Hard gale. |
|
|
70-0 |
11-207 |
||
|
50 |
73-35 |
12-300 |
Very high winds. |
|
80-0 |
14-638 |
||
|
GO |
88-12 |
17-715 |
A storm. |
|
90-0 |
18-526 |
||
|
100-0 |
22-872 |
A great storm. |
|
|
110-0 |
27-675 |
||
|
80 |
117-36 |
31-490 |
A hurricane. |
|
120-0 |
32-926 |
||
|
130-0 |
38-654 |
||
|
90 |
132-02 |
39-852 |
|
|
140-0 |
44-830 |
||
|
100 |
146-7 |
49-200 |
|
|
150-0 |
51-462 |
||
|
120 |
176-04 |
70-860 |
216
GAS ENGINEER S POCKET-BOOK.
Velocity and Pressure of Wind, (Another Kule.)
|
Miles Hour. |
Feet per Second. |
Lbs. pei- Square Fcot. |
Miles per tiour. |
Feet per Second. |
Lbs. per Square Foot. |
Miles pei- Hour. |
Feet per Second. |
Lbs. per Square Foot, |
|
1 |
1-46 |
0-005 |
18 |
26-40 |
1-620 |
35 |
51-33 |
6-125 |
|
2 |
2-93 |
0-020 |
19 |
27-86 |
1-805 |
36 |
52-80 |
6-480 |
|
8 |
4-40 |
0-045 |
20 |
29-33 |
2-000 |
37 |
54-26 |
6-845 |
|
4 |
5 -80 |
0-080 |
21 |
30-80 |
2-205 |
38 |
55-73 |
7-220 |
|
5 |
7-33 |
0-125 |
22 |
32-26 |
2-420 |
39 |
57-20 |
7-605 |
|
6 |
8-80 |
0-160 |
23 |
33-73 |
2-645 |
40 |
58-66 |
8-000 |
|
7 |
10-20 |
0-245 |
24 |
35-20 |
2-880 |
41 |
60-13 |
8-405 |
|
8 |
11-73 |
0-320 |
25 |
36-66 |
3-125 |
42 |
61-60 |
8-820 |
|
9 |
' 13-20 |
0-405 |
26 |
38-13 |
3-380 |
43 |
63-06 |
9-245 |
|
10 |
14-66 |
0-500 |
27 |
39-60 |
3-645 |
44 |
64-53 |
9-680 |
|
11 |
16-13 |
0-605 |
28 |
41-06 |
3-920 |
45 |
66-00 |
10-125 |
|
12 |
17-60 |
0-720 |
29 |
42-53 |
4-205 |
46 |
67-46 |
10-580 |
|
13 |
19-06 |
0-845 |
30 |
44-00 |
4-500 |
47 |
68-93 |
11-045 |
|
14 |
20-53 |
0-980 |
31 |
45-46 |
4-805 |
48 |
70-40 |
11-520 |
|
15 |
22-00 |
1-125 |
32 |
46-93 |
5-140 |
49 |
71-86 |
12-005 |
|
16 |
23-46 |
1-280 |
33 |
48-40 |
5-445 |
50 |
73-33 |
12-500 |
|
17 |
24-93 |
1-445 |
34 |
49-86 |
5-780 |
60 |
88-00 |
18-000 |
Formula for obtaining the Velocity of High Winds from the Pressure.
Velocity = V 10 X pressure.
Formula for obtaining the Pressure of High Winds from the Velocity.
A maximum wind pressure of 56 pounds per square foot is recom- mended in calculations for railway bridges and viaducts.
Greatest pressure of wind recorded in pounds per square foot at :•—
. 90
, . 20-2
. 65-6
, . 42-2
. 22
. 17
. 38
. 40
, 34
|
Aberdeen |
. 41 |
Liverpool |
|
Armagh . |
. . 27 |
London . |
|
Birmingham . |
. 27 |
Valentia |
|
Edinburgh |
. . 35 |
Yarmouth |
|
Falmouth |
. 53-7 |
Brussels |
|
Glasgow . |
. . 47 |
Paris . . |
|
Greenwich |
. 42 |
Bombay |
|
Halifax . |
. . 30-2 |
Calcutta . |
|
Holyhead |
. 64 |
Madras , |
|
Kew . |
, . 27 . |
WIND PRESSURES. 217
Allowance for Wind and Snow,
Weight of snow~dh horizontal surface = say 15-5 Ibs. per square foot. Wind pressure on surface at right ) . 9,i.R ir^
angles to line of impact I ~ " 2 LbS< " " "
Wind pressure on surface in spe- ) _ OI.A it,,,
cially exposed positions [--»«• ^' »
(D. K. Clark.)
According to returns- from the Greenwich Observatory during 20 years the greatest pressure equal to 28 Ibs. per square foot from the west.
Velocity of the wind (feet per second) squared x -002283 = Ibs. pressure per square foot.
At the Eiffel Tower it was found that the wind was 3 times as strong at 303 metres from the ground as it was at 21 metres, the velocity at the higher level in summer exceeding 8 metres per second during 39 per cent, of the time and 10 metres per second during 21 per cent.
Observations at the Eiffel Tower show an increase of 33 per cent, in velocity and pressure of wind per 100 feet in height.
Within certain limits the intensity of wind-pressure increases with the area of the receiving surface ; but over large areas the maximum is not reached in practice, owing to the wind moving in concentrated gusts. In designing structures, although 56 Ibs. per square foot might be looked upon as the standard, this should be modified according to the circumstances of the case, viz.: with the height from ground level, the unsupported width, and the angle of incidence. Pressures, according to received tables, varied from 16 Ibs. at ground level, to 80 Ibs. at a height of 200 feet ; and, in the latter case, from 80 Ibs. at a width of 10 feet to 40 Ibs. at a width of 1,000 feet, while the multiplier for angle varied from 0*45 at 5 degrees to TOO at 60 to 90 degrees. (Professor Adams.)
Sir G. Stokes recommends that the rate of travel of cup anemometer should be multiplied by 2-4 instead of 3 to get the velocity, and that velocity 2 x 0-0035 should equal pressure instead of velocity 2 x 0-005.
Maximum wind pressure usually allowed = O'Ol v* ; f = velocity of wind by cup anemometer.
In France velocity of storms is taken at 100 miles per hour, and pressures up to 60 Ibs. per square foot over the effective area of 1 truss of a solid truss bridge, or 1-5 trusses of an open trussed bridge.
In America wind pressures of 30 Ibs. per square foot are allowed on large surfaces and from 40 to 50 Ibs. per square foot on small surfaces.
Velocity of high v?inds =\/lo w
if 2
Pressure in Ibs. per square foot = —
Greatest wind pressures observed at the Forth Bridge were by large .fixed gauge 27 ibs., by small fixed gauge 41 Ibs., and by revolving 'gauge 35 Ibs. per square foot.
If pressure be exerted against a cylinder it tends to extend the cylinder radially in all directions. (C. Hunt.)
218
GAS ENGINEER'S POCKET-BOOK.
Gasholders are now made to stand a maximum crushing strain equalling a pressure of 20 Ibs. on the square foot, exerted on a plane represented by 50 per cent, of the area of vertical transverse section of the holder. (Newbigging, August 28th, 1888.)
Pressure on guide columns usually taken as equal to the total wind pressure divided among the guide columns upon which the rollers bear at one time, and this again divided among the different rollers to each lift.
With the upright guide form of standard they are capable of resisting the pressure of the radial rollers, while the diagonals resist the lateral strains.
Johnson's " Theory of Framed Structures " — Wind pressure P = 0*004 v 2 ; where v = velocity in miles per hour.
Mr. Cripps uses a wind pressure of 34 Ibs. per square foot.
Pressure of wind on a gasholder equals 16 Ibs. per square foot over the entire diametrical section. (F. S. Cripps.)
Wind Pressure on Circular Objects.
Let dc =j», force of wind acting parallel to the diameter "b a. Eesolve this into its component parts acting at right angles to one another at the point c, one of them./c, being a normal to the curve ; we then have/? as representing the force of the wind acting towards
the centre of the circle, and/c =p cos. angle dc f. Resolving this force / c at the point g, so as to measure the effective force exerted in the direction g, and 'parallel to the wind we have the effective pressure P =j) cos* angle A cf. This angle d cf ranges from 0° to 90°, and
WIND PRESSURES ON CURVED SURFACES. 219
taking a sufficient number of angles we obtain cos.'2' angle dcf= about -5 ; therefore mean effective pressure of wind against semi-cir- cumference P = '5/7. (Bancroft.)
Greatest wind likely to press upon gasholder equals 26 Ibs. per square foot of diametrical section of the bell.
For the reduction of wind pressure on a circular surface to an equivalent plane area (such as an arched roof or a gasholder) —
Prof. Rankine gives
M. Arson ,.
R. J. Hutton „ W. H.Y.Webber 1 .
Molesworth .,
G. Livesey .. Prof. Adams
Walmisley '., V. Wyatt
Bancroft .. Cripps
Sir B. Baker „
Newbigging ,. Trautwine
0-5
046
0-67
0-5
0-75
0-57
0-7854
0-56
1-0 (October, 1887)
0-5
0-3
0-41
0-5 area of section.
0-5 ,
Prof. Kernot (of Melbourne- University) gives ..... '. . 0-5 „ „
Prof. Kernot, of Melbourne* University, found pressure on one side of a cube = 0'9 that on a thin plate of the same area ; and in lattice work, in which openings = 50 per cent, total area, the pressure = 80 per cent, of that upon a plate = the total area. Pressure on octagonal prism = 20 per cent, more than upon circumscribing cylinder.
Pressure on sphere = 0'3G of a thin circular plate of equal diameter. Prof. Kernot also recommended 20 Ibs. per square foot as a maximum upon areas of not less than 300 square feet, and 30 Ibs. for smaller surfaces in position of full exposure.
To find approximate area of a segment of a circle, multiply versed sine by '6 X chord = area.
Cost of six-lift holder, at East Greenwich, of 12,000,000 cubic feet capacity, two upper lifts to go- outside ; framing designed by F. Livesey.
Contract amount, £41,915.
Wrought iron used ..... 1,840 tons Cast iron ,, ..... 60 „
Stoel . f ' . . . 320
Cost per 1,000 cubic feet £3 10.?. Cost of tank and holder, say £5.
Cost of gasholders equals cost of the remaining manufacturing plant. (C. Hunt.)
Cost of gasholders equals one-third of the remaining manufacturing plant. (G. Livesey.)
220 GAS ENGINEER'S POCKET-BOOK.
Notes on Guide Framing.
Guide framing must be strong enough to resist all strain from snow and wind, jamming of rollers, and guides out of plumb.
The lighter forms of guide framing depend largely upon the strength of the curb and grips to prevent distortion, but it is better to ignore this strength when calculating the guide framing, and make the latter strong enough to do all the resisting itself.
If the diagonal bracing is properly placed and of sufficient strength the greatest portion of the strain may be resisted by it.
Diagonal bracing with the old-fashioned ring for tightening in the centre is weak, coupling screws serving the purpose much better with clips where the braces cross.
Make the standard strong enough to transmit the strain from the front to the outside member.
The strain upon the uprights of a gasholder framing is a cantilever one.
In designing gasholder framing use, as far. as possible, the same size and section of iron, to avoid the expense of having a number of different pattern bars rolled. (J. Somerville.)
Wrought iron in gasholder framing has been objected to on the score of rusting, but a coat of paint every two or three years will cure this.
Gasholder guides should be fixed leaning inward slightly, according to the contraction of the curb when fully inflated.
All the wrought iron in gasholder construction should withstand a tensile strain of 21 tons per square inch, and should be absolutely tested. (J. Somerville.)
By tangential rollers the strain is thrown mainly upon the tension rods and cross girders of the framing.
Make as many triangles in the guide framing as possible in pre- ference to parallelograms.
The yielding of wrought iron or steel framing to gasholders is said to be of advantage, cast iron columns and girders having often broken through undiscovered flaws, and caused wrecking of the whole structure.
" The steadiness of a holder depends far more upon the tightness of the bottom rollers than upon any other condition. It is the practice of good gasholder erectors to make the bottom rollers fit the tank guides as tightly as they can be dropped into place." (W. H. Y. Webber.)
In Gadd and Mason's spiral guided gasholders the guides are usually set an angle of 45°.
To obtain Weight of any Holder,
Diameter2 x pressure in ^th inch X '4091 = weight of holder in pounds,
WEIGHT OF HOLDERS.
221
Diagram of Pressures thrown by Holders of Different Weights and Diameters; also Weights of Holders per one-tenth and 1 inch Pressures.
40 60
80 ioo 120 140 160 180 200 Diameters in feet
222 GAS ENGINEER'S POCKET-BOOK.
To obtain Pressure which a Holder will throw.
Weight of holder in Ibs.
Diameter* x -AOU1 -- = Pressure m *th mch-
Weight and Pressure of Holders. '
W= P x area X 5-21.
"areax 5'21 Formula for Computing Strength of a Cylindrical Beam (Cantilever).
1 = length of beam in inches ; W = weight or pressure in pounds, which will just break it.
S = coefficient of resistance to cross breaking or modulus of rupture.
I = moment of inertia of the section of the beam about its neutral axis.
x = distance in inches of the neutral axis from the extreme fibre of the cross section. (W. H. Y. Webber.)
Herr Reissner's Rule— Gasholders. Eighty per cent, of the greatest daily make as a minimum.
Formula for Strength of Columns in Multipost Type of Gasholders.
Cripps' rule for the bending moment at foot of one column or standard in foot tons, when there is only 1 lift and 1 tier of girders, and framing is carried full height of holder —
Diar. of outer lift in feet X total depth of holder when up in feet.2 Number of columns X 100
If 1 tier girders and 2 lifts X '66
11 * H ?» J) 2 '„ X *•>
it 2 „ 11 11 3 „ X "* „ 3 ,-, „ „ 3 „ X "34
Diagonal ties increase strength . . . . ith to ith
Strong cups and curbs increase strength . . . . ^th
Sheltering holder will increase strength . . . . |th
Exposed to winds, holder strength will be decreased . ith
Shallow girders badly attached will be decreased . ith to ith Standards lacking lateral or side stiffeners will be decreased ith
Bad workmanship, holder strength will be decreased Jth to ^th
GASHOLDER FRAMING. 223
Moment of Resistance of Round Cast Iron Columns. Sectional area of column in sq. ins. X diar. of column in ft. __ ^ . ^ 1-6
Moment of Resistance of Latticed or Web Plate Standards of Symmetrical Cross Section.
Wrought iron equals effective sectional area of back flange in square inches X depth of standard from front to back in feet X 5.
Steel equals effective sectional area of back flange in square inches X depth of standard from front to back in feet X 8.
Moment of Resistance of Unsymmetrical Web Plate Standards. Effective sectional area of one flange X distance of centre of gravity
of cross section of standard in feet X ' ir°n} X 2 =
moment of resistance. (Deduced from Cripps.)
For reasons of above and further information on gasholders' guide framing, see Cripps on the " Guide Framing of Gasholders."
GASHOLDERS OF CANTILEVER TYPE.
Overturning moment of wind and snow =
diar. of col.
8 X diar. of col. circle in ft, X depth of holder in ft.2 +circ]e |n ft-3
2,240 = foot tons.
Sectional Area of Single Column or Standard to Resist Lead Load. 21 x depth2 + diameter2 3,360 x No. of columns 24 x depth2 + diameter2
24 x depth2 + diameter2 I or cast iron, x NQ> qf columns = sectional area required.
For wrot. iron.
o,040 x No. of columns
tf 24 x depth2 + diameter3
itee1' . (3,720 x No. of columns = " » "
Bending Moment Due to Distorting Influence. Distance centre to centre of standards x height2 . , ,
Moment of Resistance to Distorting Influence. Distance of centre of gravity of standard from back flange x effec- tive sectional area of back flange X 2 x
224: GAS ENGINEER'S POCKET-BOOK.
Formula for Vertical Sheer.
24 x depth2 + diameter2
10,000 ~ = foot tons.
This must be resolved in direction of tie rods and struts, and divided into the different panels according to their number, in the proportion of 1 + 2 + 3 + 4, &c. = x. Therefore tension in top tie
rod = — x resolved sheer in direction of tie rods, by which strength necessary in each tie rod may be calculated.
And for calcula direction of struts.
And for calculating strength for each strut, — x resolved sheer in
NOTES ON CUPS AND GRIPS.
Weight of steel forming crown curb of 5^ million holders at Old Kent Boad equals 8 per cent, of the floating weight.
Depth of cup must allow for evaporation and tilting of holder.
Cups and grips usually have half-round iron as a bead riveted at edges.
Two channel irons have been used by Mr. C. Woodall, one at each end of first row of crown sheets, joined underneath by a second plate to form a box girder to resist compressions! strains.
Use strong bottom curbs and well adjusted rollers to them.
Blocks should be fastened in bottom of all cups for grip of next outer lift to rest on.
Guide rollers and carriages should be made strong enough to resist sudden strains, especially if no provision has been made for keeping them always close up to the guides.
The pin should be fixed and the guide roller revolve upon it.
Rule for determining the stability of the inner lift when cupped — D2 x 1(> must riot exceed weight hanging on the inner lift in pounds. D = depth in feet.
Steam should be run into lute at distances of not more than 200 feet apart, and this can be made to raise the temperature of the water to 50° F.
Inlet and Outlet Pipes to Holders should be of such size as to allow a maximum velocity of 16 feet per second when the gas is passing through them.
Horizontal and Compression Strains in tons on crown curb and on any one section of same, taken at any point, clear of all cover plates
/Vertical effective pressure in tons on ith crown area x diameter V 4 versed sine
Vertical effective pressure in tons on ith crown area x versed sine\
diameter "~ ' /°'°4
STRAINS ON GASHOLDER SHEETING. 225
or,
vertical effective pressure in tons on £th crown area x \
| m 2 versed sine , J 0*64
* diameter
or,
aP*ar> 1 2 _ vpr cineA effective pressure of gas in Ibs. per square 2 j ) foot of crown x 2 versed sine
8 versed sine
Tension strain on one foot vertical of side plates in tons = S==
Diameter — — — x pressure of gas per square foot of crown and s.ide sheets
2,240
Radius of crown in feet = R =
Diameter2 . versed sine 8 or.
2 versed sine
Mr. Wyatt says that not more than 38 per cent, of the strength of the solid unpunched plate is obtained by ordinary riveted gasholder sheet joints, and suggests using a double line of rivets to the joints, say, § inch diameter for | inch plates, put in hot without tape, and a thick coat of red lead paint in the joint ; lap say, 1| inch ; centre to centre of rivets diagonally, \\ inch ; centre to centre of rivets longi- tudinally, 1| inch ; distance between centres of rows of rivets, & inch ; by which means about 70 per cent, of the strength of the plate may be obtained.
Ordinary practice is single riveting equal to 50 per cent, strength of plate in gasholder work.
Wyatt's Rules for Strains in Gasholders.
Tangential tension strain in tons from Jth crown area ( = portion acting on one sectional area of crown curb) = T =
Vertical effective pressure in tons on ith crown area x diameter of
holder in feet ~
4 versed sine (rise in crown) or,
Vertical effective pressure in tons on ith crown area X radius of
crown in feet '•
£ diameter
G.E. Q
226 GAS ENGINEER'S POCKET-BOOK.
Tangential tension strain in tons on 1 foot length of crown sheet- ing, taken in any direction and also on 1 foot of crown curb ==1' =
/ /diameteiA 2 vpr<wi <.:„„.»} v (effective pressure of gas in Ibs. \ ( - 2 - ) j 1 per square foot of crown
4 X versed sine or,
effective press, of gas in Ibs. per sq. ft. of crown Radius of crown in ft. X —
or,
Tangential tension strain in tons from £th crown area £th circumference of holder
To find the thickness of Crown Sheets (safe strain = 5 tons per square inch) add the square of half the diameter of holder to the square of rise of crown, and multiply the sum by the effective pressure of gas in pounds per square foot, and divide the result by 5376 times the rise, multiplied by the percentage which the strength of joint bears to the solid plate. It is necessary to allow something for wear and tear, oxidation, unsound joints, riveting to thick plates, <fcc. (F. S. Cripps.)
To find the shearing strain on the rivets in top sheets per foot lineal, add the square of half the diameter of holder to the square of rise of crown, and multiply the sum by the effective pressure of gas in pounds per square foot, and divide the result by four times the rise = strain. (F. S. Cripps.)
Mr. Livesey found an average contraction on a holder 180 feet diameter of O6125 inch on lifting the inner holder, a further con- traction of O3375 inch on lifting the outer holder, making a total contraction of 0'95 inch, of which O169 inch contraction remained as a permanent contraction when the holders were again landed.
The cup and lower curb plate should be made stronger than the rest as they cannot be painted.
It can be shown that only a few of the outer rings of crown sheets are in compression, say two or three rows and one row of side sheets.
Formula to Obtain the Tension on the Sheet Iron next Curb. (Arson.)
Weight of sides IT diameter X sin. of angle of top sheets with horizontal
Formula to Obtain the Tensile Stress on the Rivets. (Arson.) "Wei eh t of sides
TT diameter
cos. of angle.
STRAINS OX GASHOLDER CURBS, 227
Formula to Obtain the Crushing Stress on the Curb. (Arson.) Weight of sides
18-3
angle of top sheets with horizontal
Rule to Find the Compressive Strain on a Gasholder Curb.
(Half the diameter of holder2 - rise2) x pressure of gas in Ibs. per
square foot x diameter of holder
llise x 8
Strain (compressive) in pounds due to the pull of the top sheets ; to this add depth of inner lift x 6'5 X diameter of holder for the pressure of wind, less dimeter of holder x depth x actual pressure
of gas for the pressure of gas on the sides.
The constant 10 is used for vertical stays fastened all the way up. The constant 16 is used for vertical stays loose. Difference equals compressive strain on top curb. (Deduced from Cripps.)
Q 2
228 GAS ENGINEER'S POCKET-BOOK.
WORKSHOP NOTES.
Wyatt's Rule. — Three hundred and seventy cubic feet of work- shops and offices required per ton per diem (dwelling-house included).
Best Speed for Cutting Tools when Working. Steel . . .12 feet per minute. Cast iron . . 18 „ „
Brass . . . 24 „ „
Wrought iron . 24 „ „
Wood . . 2,000 „ „ when material revolves.
„ . .3 000 „ „ when tool revolves.
Grindstone . . 800 „ „
Circular saws should be run at about 9,000 feet per minute on the teeth.
Band saws should be run at about 4,000 feet per minute. Planing and moulding rotary cutters, 5,000 feet to 7,000 feet pel minute on cutting edge.
Emery discs, 4,000 feet to 6,000 feet per minute on periphery. Drills for wrought iron should have circumferential speed of 140 to 160 inches, and for cast iron 80 to 120 inches. Another authority gives —
Speed of Cutting Tools.
For Cast iron 150 to 190 inches per minute.
„ „ (boring) 80 „
Wrought-iron .... 260 to 280 „ „
Yellow brass 300 „ „
Band saw for metal .... 250 feet „ „ ,. „ wood . . . 4.000 ,. „ Teeth of circular saws . . . 9,000 ,. ,. Cutter blocks for planing and mould- ing wood (cutting edge) . . 6,000 „ ., Irregular moulding and shaping
machines, wood (cutting edge) . 5,000 „ „
Saw and cutter sharpening machine 5,000 „ „
General Notes.
A man will pull or exert an effective power of 35 Ibs. in fair working.
Angles of cutting tools : — Wood, 30 to 40 degrees ; wrought iron, 60 degrees ; cast iron, 70 degrees ; brass 80 degrees.
Circumferential velocity of drill should equal about 100 inches per minute for cast iron and 150 inches for wrought iron.
Circumferential speed of emery wheels, about 5,000 feet per minute. ,, „ of grindstones, „ 800 „ „
The diameter of the hole in the die should exceed the diameter of the punch by about one fifth of the thickness of the metal to be punched.
The die first used was 36 millimetres in diameter ; afterwards one cf 39 millimetres in diameter was substituted without altering the size of the punch. The hole made with the 36-millimetre die under- neath was cylindrical, but with the 39-millimetre die it was conical.
STATION METERS.
229
The amount of clearance between punch and die should equal one fifth the thickness of metal to be punched.
Diameter of die equals diameter of cutting edge of punch -f 0'2 X thickness of plate to be punched.
Two pieces of aluminium or platinum pressed together for eight hours at 330° C. will cohere.
Iron castings contract about Jth inch per foot ; brass castings, about ^jths inch per foot.
Allow §rds of the width of rails for mortices and |rd for haunching.
Approximate quantity of air required for welding in a smith's forge equals about 150 cubic feet per minute.
Station Meters.
Choose a station meter in which the spout is kept wen a Dove the water line, and see that the bearings and stuffing box can easily be got at for examination and repair. See that no useless metal is put into the drum, causing weight and consequent pressure to turn. Have sufficiently large openings in the hoods to allow an easy passage of the gas on both inlet and outlet ends of the drum.
To Find the Capacity of a Station Meter Drum.
Find the area of a circle of equal diameter to the diameter of the drum («). Multiply by the average depth from centre of hood space on outlet end to centre of hood space on inlet end (&) above
the water line, and deduct from this a square equal to twice the water line above the centre of the drum (d) multiplied by length from inlet to outlet sides of drum on water line (e).
Herr Keissner's Rule — Station Meters, — Allow 80 revolutions per hour as a maximum.
230
GAS ENGINEER S POCKET-BOOK.
The openings in the centres of station and other meters should be such as to allow the water to pass easily from one chamber to another, so as to relieve the pressure upon the partition. The same applies to the raising of the water line, which may cause the immer- sion of the partitions to such an extent as to cause a perceptible drag on the revolution of the drum.
Dimensions of Square Station Meters.
|
Capacity per Hour at 100 Revolutions. |
Capacity per 1 Revo- lution. |
Side to Side. |
Front to Back. |
Height. |
Diameter of Drum. |
Length of Druni. |
Diame- ter of Connec- tions. |
|
Ft. Ins. |
Ft. Ins. |
Ft. Ins. |
Ft. Ins. Ft. InsJ Indies. |
||||
|
20.000 |
200 |
9 3 |
8 6 |
9 6 |
8 0 |
7 6 |
12 |
|
25,000 |
250 |
9 3 |
9 3 |
9 6 |
8 2 |
8 0 |
12 |
|
30,000 |
300 |
10 0 |
10 0 |
10 9 |
8 7 |
8 6 |
14 |
|
40,OCO |
400 |
11 3 |
11 3 |
12 0 |
9 9 |
9 0 |
15 |
|
50,000 |
500 |
12 0 |
12 0 |
13 0 |
10 6 |
10 6 |
16 |
|
60,000 |
600 |
12 0 |
13 0 |
13 0 |
10 6 |
11 6 |
18 |
|
80,000 |
800 |
13 6 |
13 6 |
14 0 |
12 0 |
11 6 |
20 |
|
100,000 |
1,000 |
15 4 |
15 0 |
16 6 |
13 6 |
11 6 |
24 |
|
125,000 |
1,250 |
15 4 |
15 0 |
16 6 |
14 0 |
12 4 |
24 |
|
150.000 |
1,500 |
15 6 |
17 6 |
15 5 |
13 6 |
14 2 |
24 |
|
250,000 |
2,500 |
20 6 |
19 3 |
21 0 |
18 0 |
15 0 |
30 |
Bound Station Meters.
|
Capacity per Hour. |
Capacity per Revolution. |
Diameter Inside. |
Depth Inside. |
Diameter of Flanges. |
Diameter of Con- nections. |
|
Ft. Ins. |
Ft. Ins. |
Ft. Ins. |
Inches. |
||
|
600 |
5 |
2 3 |
2 3 |
2 9 |
2 |
|
900 |
7'5 |
2 10 |
2 3 |
3 4 |
3 |
|
1,200 |
10 |
3 2 |
2 8 |
3 8 |
3 |
|
1,500 |
12-5 |
3 4 |
3 0 |
3 10 |
4 |
|
1,800 |
15 |
3 6 |
3 4 |
4 0 |
4 |
|
2,400 |
20 |
3 9 |
3 6 |
* «i |
4 |
|
3,000 |
25 |
4 0 |
4 0 |
4 7 |
5 |
|
3,600 |
30 |
4 3 |
4 2 |
4 10 |
6 |
|
4,000 |
40 |
4 9 |
4 6 |
5 4 |
6 |
|
5,000 |
50 |
5 0 |
4 8 |
5 7 |
6 |
|
6,000 |
60 |
5 0 |
5 4 |
5 7 |
8 |
|
7,000 |
70 |
5 6 |
5 6 |
6 1 |
8 |
|
8,000 |
80 |
5 10 |
5 8 |
6 5 |
<S |
|
10,000 |
100 |
6 4 |
6 2 |
6 11 |
<) |
|
12,500 |
125 |
6 10 |
6 2 |
7 5 |
10 |
|
15,000 |
150 |
7 0 |
7 10 |
7 7 |
10 |
|
1 7,500 |
175 |
7 3 |
7 6 |
7 10 |
12 |
|
20,000 |
200 |
8 0 |
7 6 |
8 7 |
12 |
|
25.000 |
250 |
S 0 |
9 6 |
S 7 |
12 |
|
30.000 |
300 |
8 5 |
9 8 |
9 0 |
14 |
MANUFACTURING. 231
STORING MATERIALS
Coal when exposed to the air changes in character, the change consisting in a diminution of agglomerating as well as of lighting power, and probably also of heating power.
The change is more rapid the higher the temperature and the more divided the coal.
In the small pieces the change in the character of the coal is greater on the surface than in the interior. In heaps of coal per- meated by the air the change is greater in the centre than on the surface. When the air cannot penetrate to the centre the surface undergoes the greatest change.
Small coal washed is less liable to change than unwashed.
Large pieces of coal are only liable to change after a certain number of years' exposure to the air. The small coal is affected very quickly if it happens to be under conditions likely to raise its temperature.
In a few months it is capable of entirely losing its agglomerating and lighting power. Heaps of small coal become heated, but stacks of large coal do not heat to an appreciable degree.
Small coal should not be stacked in too large heaps.
Coal stacked in low heaps does not become heated. Heat increases with the height of the stack, and at about the height of 3 or 4 metres the temperature rises progressively and then descends without having exceeded 60° C. or 70° C.
The inner temperature of a stack 2 metres high does not usually exceed 40° C. to 50° C. (M. de Lachomette.)
Storing coal in the open may cause a loss of from 30 to 40 per cent, in the quantity of gas to be obtained from it.
North Wales coals and certain cannels are said not to depreciate appreciably through exposure when stored in the open, while certain Scotch coals have been known to lose 50 per cent, in value in 3 months.
All coals exposed to the air absorb oxygen, the volume of which may be 100 times that of the coal.
The loss and increase of weight are produced more slowly the larger the pieces of coal. (M. de Lachomette.)
The yield of gas from coal before exposure being equal to 26*30, fell to 6-60 after being subjected for 4 days to 400° C., and at 8 days to nil. The illuminating power also diminishing very quickly. (M. de Lachomette.)
Powdered coal containing from T6 to S'3 per cent, oxygen when subjected to the prolonged action of air and of stagnant and running water is not appreciably affected with regard to composition, yield of coke, or calorific power. (M. Georges Arth.)
The drier the coal when stacked the less the liability to heat, and all trampling or compression should be avoided.
The only thing to be done with heated coal is to open it out and allow it to cool, or the heating will spread.
M. Morin suggests connecting the two ends of a thin platinum wire, about 0-0008 inch diameter, laid through the thermometer to a
232 GAS ENGINEER'S POCKET-BOOK.
battery and galvanometer, when the varying resistance due to the rise and fall of the mercury will be shown upon the galvanometer, and the temperature of anything may be observed at a distance, such as in a heap of coals.
Another form of indicator for showing when coals are heated above a certain temperature might be made by means of the two wires from a battery covered with gutta-percha and the one wound round the other, so that when a sufficient heat was formed to melt the covering the two wires would be in contact, and could be made to ring an electric bell.
Igniting Points of Coals. (V. B. Lewes.)
Cannel . . . 698° F. = 370° G.
Hartlepool . . . 766° „ = 408° „
Lignite . . . 842° „ = 450° „
Welsh steam . . . 870£° „ = 477° „
When Wire Ropes have to run over small pulleys or capstans the number of wires should be increased. In the case of cranes sometimes as many as 270 are used.
Average consumption of Coal per Passenger Train Mile equals 30 Ibs., or about 1| Ib. to If Ib. for hauling 10 tons 1 mile. Consumption of coal per square foot of firegrate per hour varies from 60 Ibs. to 80 Ibs.
When large Stocks of Coke are stored in the open an increase in weight of 15 to 20 per cent., due to wet weather, has at times been found. (C. Gandon, Gas Institute, 1887.) See also p. 145.
Stacking coke in large quantities deteriorates the quality.
100 Ibs. coke can absorb 50 Ibs. water.
Increased quantity of breeze due to use of coke breaker only about 5 per cent, of coke broken, or 1 cwt. per ton of broken coke for sale. Less when broken while warm (say 1£ bushels per ton).
Oils flashing below 73° F. are not allowed to be stored in warehouses or shops in England.
CARBONIZING. 233
RETORT HOUSE MANUFACTURE.
The gas produced in part of the retort nearest the front is not usually so good in quality or quantity as that from other parts.
Uneven charging reduces the temperature of the retorts and makes a poorer coke.
Uneven charges cause the evolution of gases of little or no illu- minating power from the thin portion, while the thicker portion is not properly burnt off in the allotted time, and gas is lost.
Eetorts which allow but little room above the coals are to be preferred, as then the gas passes quickly away from contact with the heated surface of the retort, which causes the decomposition of some of the olefiant gas.
The production of the hydrocarbon compounds from the coal takes place at a comparatively low temperature ; these hydrocarbon com- pounds are then broken up into simpler forms by the passage through the retort and exposure to its heated sides.
Deep charges cause caking of the outer portion before the inner is worked off, the outer portion having been quickly gassified. The coke then is giving off sulphur. The thick charge cools the retort, and the gas then made is less and the tar high. (G. Anderson.)
Charge should fill the retort as full as will allow convenient charging and drawing.
Deep charges of coal cause caking on the exterior for some hours before the interior of the charge is worked off.
The whole of the outer surface is giving off sulphur for some hours after it has given off its gas.
The large mass cools the retorts for some time, while tarry vapours are being formed instead of gas.
Large retorts at low heats conduce to deposition of soot and napthalene.
The sulphur given off from damp coals is greater than from dry.
At high temperatures the gas produced contains methane (CH^.) and free H ; and more free C in the tar and in the compounds of carbon belonging to the aromatic series derived from benzene (C6H6) and H is separated, and napthalene, anthracene, phenanthrene, chrysene, &c. are formed. (Dr. Lunge.)
At low temperatures the hydrocarbons formed belong to the paraffin series (methane), having the general formula Cn~H.2u + 2, along with olefines (CwH2%). (Dr. Lunge.)
With low heats the yield of ammonia is generally lower, which is also the case with high makes.
Low temperatures, with 9,000 dubic feet of gas per ton, will yield, with a certain coal, 16 gallons tar, but the same coal at high tempera- tures will yield 9 gallons tar and 11,000 cubic feet of gas. (Davis.)
If coal were distilled at low temperatures and the gases afterwards subjected to greater heat in separate retorts, where the heat could be accurately controlled, better results might accrue. (Foulis.)
Mr. Hunt, testing in a small iron retort, found that the greatest number of candles per ton was obtained with a temperature of
234 GAS ENGINEER'S POCKET-BOOK.
1,GOO°F., and he considers the best heat for ordinary working is the lowest that will thoroughly carbonize in the allotted time, the stopped pipes with high heats causing loss beyond the gain by the higher temperatures.
There is a certain temperature at which each coal may be made to yield the best results, both as to quantity and quality.
When gas is being evolved from coal the temperature of the retort is not even along the length of the retort.
When a substance is subjected to a high heat and to an advanced state of decomposition the products produced are generally of a simple nature.
The higher the heats the greater the proportion of hydrogen and methane and the lower that of C.
Temperature in retorts = 1,800° to 2.000° F. = temperature in hydraulic main of only 140° to 180° F. = 110° to 150° F. at outlet of latter. (J. Hornby.)
Temperature in retorts rarely more than 2,200° F.
Cherry red is the best heat for iron retorts.
A good orange is about right for clay retorts.
If the heat of retorts is' 1.000° C. (1,832° F.) before the charge is in the heat of the coals near the walls will be about 800° C. (1472° F.) and in the centre of the coals 400° C. (752° F.).
The upper layer of evolved gas will be at a temperature of 1.000° C., and the lower, near the coal, 600° C. (1,112° F.) (Prof. Lewes.)
If a long piece of gas piping, closed at one end, is passed through a hole in the retort lid with the open end to the air it can be used "to obtain the heat of the retort at different points. (L. T. Wright.)
The velocity of gas in its passage through highly heated retorts is about 5 feet per second during the maximum evolution of the gas.
Damp coals cause steam in the retort, which is afterwards condensed in the condensers, and which has a tendency to lower the tempera- ture of the retort.
Loss between working in summer and winter equals 9'6 per cent, in favour of the former, in the sperm value obtained from similar coals.
Very high yields of gas are only obtainable with excessive use of fuel.
Clay retorts usually worked at 1,082° C.
At a yield of 118 cubic feet per square foot of retort, cast iron could be melted (= + 2,100° F.) in the top flue, and silver in the bottom flue ( = + 1,749° F.).
The greater proportion of the CS2 is formed after the useful gases have been driven off from the coal, and is increased if the coal be wet when put in the retort.
Best temperature for Newcastle coal is dull orange or 2,010° F.
Clay retorts 'are bad absorbers of heat compared with iron retorts.
Water vapour in the retort seems to have some protective action on napthalene. (L. T. Wright.)
The maximum production per square foot of retort surface may be taken as 126 cubic feet per ton, or 14-7 tons of coal carbonized per 1,000 square feet per 24 hours.
There are certain paraffin hydrocarbons in the coal which arc split up into simpler members of the same series and into defines
TEMPERATURE OF DISTILLATION. 235
Fractional distillation is a means of separating liquids with boiling points at least 30° F. apart,
Cannel coal carbonizes in about five-sixths the time of caking coal, and the greatest quantity of gas is evolved during the first hour of charge.
Temperature of gas as it leaves the coal about 170° F.
The more rapidly the coal is carbonized the better are the results. (W. Foulis.)
Products of Distillation of Newcastle Coal at Usual Heats.
(Prof. Wanklyn.)
Ibs. per con
Gas (10.000 cubic feet) . . 380 . 17-0
Tar (10 gallons) 115. . . 5-1
Virgin ammoniacal liquor . . 177 . 7'9
Coke (absolute) . . . . . 1568 . . . 70*0
Residuals and Impurities at Outlets of Retorts in Percentage by Weight of Crude Gas. (Prof. Wanklyn.)
Tar 33 per cent.
Watery vapour 50 „
Ammonia 2 ,,
C00 5
H2"S 2 to 5 .,
S. as sulphuret of carbon and organo-sulphur compounds '15 to *3 .,
Result of Heating to about 1000° C. (Prof. Lewes.) Ethane becomes ethylene and hydrogen. Ethylene „ methane and acetylene. Acetylene „ benzene, styrolene, retene, &c.
Variation in Quantity of C02 and H2S according to the Heat of Distillation. (Lewis T. Wright.)
|
CAKING COALS. |
||
|
Yield of Gas per Ton. |
Grs. of CO2 per Cubic Foot. |
Grs. of H2S per Cubic Foot. |
|
7,856 8,547 11.128 |
16-92 18-38 19-37 |
3-16 4-69 5-87 |
|
CANNEL COAL. |
||
|
7,853 10,047 |
32-60 39-27 |
4-80 4-97 |
The '• salts " usually found mixed with tar in the hydraulic and foul mains are probably sal-ammoniac, and are formed by high heats.
Crude gas contains about 1 per cent, ammonia, weighing from 51 Ibs. to 8 Ibs., and about 5 per cent. C02 and H2S.
236
GAS ENGINEER'S POCKET-BOOK.
Result of Carbonization at Different Temperatures. (L. T. Wright.)
|
Temperature. |
Gas. Cubic Feet perTon |
Illu- minat- ing power |
Candles pei- Ton. |
H. per Cent. |
Me- thene per Cent. |
Ole- fines per Cent. |
CO. per Cent. |
N. per Cent. |
|
Dull red. Hotter . Bright orange |
8,250 9,693 10,8'_'l 12,00(5 |
20-5 17-8 10-7 15'0 |
33,950 34,510 3(5,140 37,4(50 |
38-09 43-77 Testlos 48-02 |
42-72 34-50 Test lost 30-70 |
7-55 5-83 Test lost 4-51 |
8-72 12-50 Test lost 13-90 |
2 "92 3-40 Test lost 2"81 |
At a low rate of distillation nearly all the gas is evolved at 1,340° F.
At the highest rate of distillation 66 per cent, of gr.s is evolved at 1,339° F.
When the yield of gas per ton is under 9,000 cubic feet the temperature of the bottom flue is not above 1,580° F., but with a temperature there of 1,680° F. the yield increased to 9.378 cubic feet per ton. (L. T. Wright).
|
Temperature of Retort. |
Make of Gas. |
Gallons of Tar. |
Remarks. |
|
600° F. 750° to 800° F. 1000° F. ]830°F. 2010° F. |
Feet per ton. 400 1,400 6,000 8,300 10,000 |
68 13 to 14 gals. 9 |
coke very friable. faint red heat, bright cherry red heat, orange heat. |
Low temperatures give little ammonia. Medium temperatures give most ammonia.
Higher temperatures give rather less ammonia but more CS0, H2S, and cyanogen.
|
Make per Ton, Cubic Feet. |
NH3 per Ton. |
Percentage of Coal as NH3 |
|
|
11,620 10,162 9,431 7,512 |
Ibs. 7-411 7-894 7-504 6-391 |
0-331 0-352 0-335 0-285 |
|
|
Temperature of Retort. |
Make of Gas. |
Illuminating power |
Illuminaiits. |
|
2,000° F. 2,160° F. |
Per Ton. 9,800 11,000 |
Candles. 16-54 12-00 |
Lbs. Sperm. 5251 452^ |
(L. T. Wright.)
HOURLY MAKE OF GAS.
237
Coal carbonized at 2,000° yielding 9,800 cubic feet of 16-54 candle gas equal to 555^ Ibs. illuminating matter, but if carbonized at 2,100° will yield 11,000 cubic feet gas of 12 candle-power equal to 452 £ Ibs. illuminating matter.
If caking coal be carbonized at 600° F. (hardly red in a dark place) only 400 cubic feet of gas per ton are evolved, and most of the hydrocarbons are resolved into tar.
At low heats 600° F. tar and oils are formed but little gas, while at higher heats gas is formed with less tar.
At a low red heat in daylight about 6.500 feet are produced per ton.
At 750° to 800° F. about 1,400 cubic feet gas and 68 gallons tar or crude oil are given off ; at 1,000° (a faint red in subdued day- light) about 6,000 cubic feet gas ; and at 1,830° (a bright cherry red) about 8,300 cubic feet with 13 or 14 gallons tar are evolved ; and at 2.010° (orange) about 10,000 cubic feet per ton with 9 gallons tar. (Gesner.)N
Composition of Gas from Newcastle Coal Carbonized at Different Heats. (Thorpe.)
Gas per ton of coal, cubic feet . . 8,250 9,692 12,006
Illuminating power, candles . . . '20'59 17*80 15*60
Unsaturated Hydrocarbons, per cent. 7*55 5 '83 4*51
Marsh Gas 42-72 34-50 30'70
Carbon Monoxide . 8'72 13-50 13'96
H 38-09 43-77 48-02
N 2-92 2-40 2-81
Percentage and Specific Gravity of Gas .during each of Five Hours' Charge.
First hour 46-6 per cent, gas given off -677 average specific gravity. Second hour 27-4 „ „ „ „ -419 „ „ " „
Third hour 16-0 „ „ „ ,. -400 „ „ „
Fourth hour 7-3 „ „ „ „ -322 „ „ „
Fifth hour 2'7 —
Another experiment gives
First hour 5T3 per cent, gas given off specific gravity not taken.
Second hour 33-5
Third hour 11-8
Fourth hour 3-4
1 ton coal distilled at about 1.650° F. will be 'carbonized in 6 hours. 2,010° F. „ „ 5 „
2,190° F. , „ „ 4 „
The greatest quantity of gas from caking coal is evolved during the second hour. -
238 GAS ENGINEER'S POCKET-BOOK.
Wigan Cannel (1 ton) produced
First hour 3,320 cubic feet.
Second hour .... 2,940 ,,.
Third hour 2,6(50 „
Fourth hour .... 1,040 ,.
(Herring.)
Six-hour Charges.
At end of first hour one- sixth of the total quantity of gas is given off, at commencement of second hour the coal becomes soft, and during the second, third, and fourth hours yields gas from innumerable small jets, at the fifth hour it is compact and doughy, the gas issuing from throughout the mass. At the commencement of the" sixth hour it is still black as at first, and the evolution of gas, which has been fairly uniform, commences to decrease very rapidly. At 5£ hours gas almost ceases to issue, and coke becomes incandescent and brittle.
Quality of gas nearly uniform for first five hours, but deteriorates greatly the last hour, often being not more than 3 candles.
Four-hour Charges.
Periods of three-quarters of an hour correspond to those of one hour in above remarks.
The work done in the retort during the last hour of the charge. amounting to about 5 per cent, of the whole, is also getting the retort in a condition of heat to receive the next charge. It has been proposed by the " Journal of Gas Lighting " to connect the mouth- piece of the retort by means of, say, a 2-inch or 3-inch tube, provided with a cock, with the interior of the setting, and divert the gas yielded during the last hour of the 6-hour charge, so that it may assist in heating the retorts, and not deteriorate the quality of the gas already made.
First hour } volume of 10 candles ; second hour and half, £ volume of 17 to 18 candles ; third hour. \ volume of 14 candles ; remainder, 8 to 10 candles at high heats, making 11,000 feet gas of 14 candles. (Butterfield.)
Gas Iriade per cent.
1 16-6 Gas strongly impregnated with tar.
2 .... Coal becomes soft.
3 . . . . In a state of intumescence and
yielding.
4 . ... Gas from innumerable small jets.
5 . , . . A compact and doughy mass.
(5 . . . Coal still black, yield of gas
decreasing rapidly, sulphur compounds being evolved, quality about 3 candles.
CLIMATIC EFFECTS ON DISTILLATION.
239
From tests of a Scotch coal, giving an average of 11,250 cubic feet per ton of 30-18 candle power, Mr. W. Wallace, F.I.C., found a variation both in illuminating power and pounds of sperm per ton, according to the temperature : —
|
Lbs. Sperm per Ton. |
Illuminating Power. |
|
|
In January |
1,136 |
29-44 |
|
, February . . . |
1,140 |
29-56 |
|
March |
,122 |
29-08 |
|
April . . . . |
.135 |
29.41 |
|
May . |
,218 |
31-58 |
|
June . . . ' . . |
,208 |
31-32 |
|
July . L V<>. . |
,209 |
31-34 |
|
August . " . . |
,209 |
31-34 |
|
September . ?- • . v |
1,178 |
30-54 |
|
October . . . . |
1,146 |
29-72 |
|
November . |
1,139 |
29-53 |
|
December . , . |
1,124 |
29-14 |
|
Average . |
1,164 |
30-18 |
Or by temperatures —
|
Degrees Fahr. |
Lbs. Sperm per Ton. |
Illuminating Power. |
|
36 to 40 . |
1,108 |
28-73 |
|
41 to 45 ..' '-: .••;•'. .' • i.-j--; |
1,124 |
29-14 |
|
46 to 50 . ; -." .. <*?& |
1,142 |
29-61 |
|
51 to 55 - - > Tie -j- •: |
1.182 |
30-65 |
|
56 to 60 . . * .'»-: •-. trwj |
1,206 |
31-27 |
|
61 to 69 &i .:.Y . . |
1,215 |
31-50 |
|
Average . |
1,163 |
30-15 |
Proportions of coal, coke, and tar used per ton in firing retorts : —
2f cwts. of coke are used per ton of coal carbonized with gaseous regenerative firing.
3£ to 4£ cwts. of coke are used per ton of coal carbonized with ordinary furnaces.
1 ton of tar is equal to about 2 tons of coke in firing.
Experiments as to quantity of fuel required in a regenerative setting ; 1 generator to 2£ settings per diem : —
Tons. Cvvbs. Qrs. Lbs.
Breeze consumed 14 3 10
Cold coke . . . . . 4 13 3 4
Clinker extracted 2 0 1 12
Coal carbonized (estimate!). . .27 000
Gas made per mouthpiece (estimated) 5,700 cubic feet.
240 GAS ENGINEER'S POCKET-BOOK.
Pounds fuel used per 100 Ibs. coal carbonized :—
Coke Breeze
17-36 Ibs. 2-74 Ibs.
The above are calculated from the quantity used in a week of 6£ days.— March 21st, 1892.
Composition of Gases in Generator Furnaces,
|
EBELMAN'S GASOGENE. |
SIEMEN'S GENERATOR. |
|
|
Air. |
Air and Steam. |
|
|
CO . C02 |
33-3 0-5 |
27-2 2G-0 5-5 4.5 |
|
N 0 H |
63-4 2-8 |
53-3 07-5 — 0-5 14-0 — |
|
100-0 |
100-0 100-0 |
First analysis most like the exact chemical proportions for the entire conversion of carbon into CO without COa which are 34| per cent. CO and 65J per cent. N.
Amount of Primary and Secondary Air should be tried and fixed in each case when using regenerator furnaces.
Best materials only should be used in such settings.
Areas of openings for introduction of primary and secondary air and gas ducts vary considerably, and should all be made so that they can be altered as required by a sliding brick or tile.
Only a comparatively low temperature is required to convert fuel to CO, and thus the admission of cold air under the furnace barg enables the furnace to last long, owing to less wear and tear, and prevents the formation of clinker, ash only being found between the bars.
In regenerator furnaces the gases, before combustion, should be of uniform quality and temperature, and should then be directed into and distributed over all the interior of the setting.
The arrangement should be such that combustion shall not be complete until just before the burnt gases are leaving the setting and are about to enter the flues of the regenerator.
The limit of heat which may be employed in a set ting is the fusible point of the brickwork in the hottest part, and the producing power of the setting is governed by the temperature of its coldest part.
It is impossible to introduce air into a gas-fired retort setting and properly distribute it for combustion, without it becomes heated to the necessary temperature for combustion with the primary gases.
It is only by analysis of the gases that it can be accurately ascer- tained if the primary and secondary air are being used in their proper proportions.
With ordinary settings M. Euchene calculates that 12'8 per cent, of heat evolved from the coke, etc., is lost by radiation through walls, etc-
REGENERATIVE SETTINGS. 241
Secondary air should be heated to about 1,800° F.
One half the heat generated by the combustion of fuel is made when CO has been formed, a further half being generated when this is converted into C02
Saving in fuel with generator settings = about 25 per cent.
„ ,, ., ., regenerator „ = ., 50 „ Theoretically 1.100° F. are required in the producer. Practically 1,800° F.
Composition of producer gases by volume.
CO .... 25-7 per cent. CH, .... 2-75 .,
H 14-06
N 52-74:
C02 . . . . 4-75 „
Temperature at combustion chamber . 2,600° F.
., ., crown of setting . . 2,400° F.
,, ,, entrance to regenerators 2,150° F.
„ ,. outlet of last waste gas flue 1 ,000° F.
The smaller the percentage of ash in the coke used for regenerative firing the better, but, if porous, 10 per 'cent, of ash can give good results.
A vacuum of three-fifths is sufficient at outlet of last waste gas flue.
Analysis of gas at last waste gas flue : —
CO . . .0-7(0 . . .0 C02 . . . 16-6 |N. . . . 83-3
Of each 1 Ib. coke placed in regenerator furnaces,
18 per cent, is ash, 78f ., „ carbon,
3* ;, ,; H.
Of the carbon 90 per cent, is converted to CO and requires for complete combustion about -45 Ibs. 0.
For the hydrogen about -26 Ibs. 0 is required, or a total of -71 Ibs. 0 equal to 3'1 Ibs. of ordinary air to be raised, say 1,800° F.
Specific heat of air = 0*2374, therefore 3'1 Ibs. x 0'2374 x 1800 = 1324-7 units of heat.
There is always a considerable loss of heat through the N. passing away hot into the air.
No gain of energy with gaseous fuel, but rather a loss. The advantages being that the absolute conversion into C02 can be made to take place at any or several desired points, which might be impossible to reach by means of direct firing, and, again, the loss of heat which is radiated from the furnace in a direct fired oven is not so great, as the intensest heat is only obtained at the point where the heat is required.
242 GAS ENGINEER'S POCKET-BOOK.
Heat in recuperators should not be more than a dull red below the secondary air inlet, as this will probably mean too little secondary air being used.
No blue flame should be visible at outlet of flue, as this shows unconsumed CO.
About one-third the total heat evolved by the fuel is used in transforming the solid into gaseous fuel.
Producer gas in Siemen's furnace with coal containing 70 per cent, fixed carbon, 16 per cent, of coal gas, 14 per cent, ash oxygen and nitrogen (coal equals about 7,200 calories). Producer gas consists by weight of 16 parts coal gas, 163 '3 of CO, and 222 of N.
Coal gas = 10,000 calories, CO = 2,400 calories, then the total calories = 551,920 against 700,000 for the coal proper. (Sir J. Lowthian Bell.)
2 to 3 per cent. C02 in generator gases shows very good working. 5 to 6 „ ., „ ., fair „
10 „ ., „ „ defective „
(W. Thorner.)
Wide furnaces prevent the fire burning too low.
There should be no exhaust on furnace except when drawing up the heats.
Less air is required with a light than a heavy coke.
Ordinary furnaces allow a large proportion of the CO to escape without being oxidized to CO2.
About 25 per cent, of the heat evolved in an ordinary furnace passes up the chimney, of which only one-fourth is required for the necessary draught.
Breeze consists of much earthy matter, and but little carbon, which makes it a weak fuel, and much scoriae is deposited \vheu burning it.
Briquettes are made on the Continent to burn coke dust and tar or pitch for heating the furnaces. Tar and coke dust are sometimes mixed on the retort house floor and then used as fuel.
Briquettes are also made by hydraulic pressure, the proportions being 10 per cent, pitch to the quantity of breeze.
Clegg stated that when tar was less than 3d. per gallon it paid to burn it in the furnr.ces, at present it only pays to burn when less than £ d.
Advantage of tar firing is the slow and even rate of supply as compared with coke firing, by which the necessary air supply is much lessened, and the consequent cooling effect of the inert gases is not BO great.
The superiority of liquid fuel over solid is principally due to the H contained in it, H evolving five times the heat, weight for weight that carbon does on combustion.
The use of steam does not appear to have any beneficial effect when employed to inject tar into retort furnaces ; it has been shown by Mr. Dexter that no increased heat can possibly result by its use, but that rather does it tend to lower the heats.
Twenty gallons tar required to carbonize 1 ton coal equals about 6 gallons tar per 3 bushels coke.
REGENERATIVE SETTINGS. 243
Provide a good quantity of water in the ash pans as the steam prevents the formation of clinker, and prevents the over-heating of the fire-bars.
It is a moot point if the water gas made from the evaporation in the ash pans is an advantage or not, the amount of heat absorbed in converting water to 0 and H being very great, but being taken from the lower layers of the furnace it does not materially affect the heat of the bulk of the fuel, while the gain from the burning of the hydrogen is considerable.
A jet of steam is of assistance under the bars of generator settings.
The steam from the ash pans is converted into CO and H in passing through the red-hot fuel in the furnace.
Quantity of water evaporated per furnace per hour equals about 3 gallons.
Steam required for producer equals about 32 Ibs. per 100 Ibs. C consumed or 3-70 Ibs. water per 100 Ibs. coal carbonized.
Clinkering is reduced about one-third in regenerator settings.
Clinkering should be done often enough to prevent such an accumulation as will stop the air-way between the fire-bars.
Clinker is due to the combination, under the influence of heat, of the inorganic, or incombustible matter of the coke (the ash of the coal). This consists principally of silica, alumina, lime, iron, &c., which fuses together to form a kind of slag. (Hornby.)
Furnaces require repair about every six months.
Average life of clay retort 900 working days.
Clay retorts will carbonize about 4.000,000 cubic feet.
Iron retorts about 050,000 cubic feet of gas, and they arc done.
The broken surface of a brick is much sooner acted on by heat than is the smooth face which has a protecting skin upon it. Lumps are therefore to be preferred where possible.
The saving due to the producer may be taken at 52*20 per cent. t, ., regenerator ,. ., 47-74 „
100-00
If a blue flame is seen at outlet of chimney of regenerative retort settings CO is being passed away, and more secondary air should be let in.
Generator gas should consist of 34*7 per cent. CO and 05-3 per cent. N.
Chimney gases should contain 21 per cent. C00. 1 per cent. 0 and 78 per cent. N.
Air rapidly absorbs heat, and when passed over heated surfaces it becomes raised in temperature approximating closely to that of its surroundings.
The waste gases in a regenerator setting have been known to be reduced in temperature from 1,200° F. to 500° to 000° F. by the incoming of the secondary air, all of which heat is being saved and used again in the furnaces.
B2
244 GAS ENGINEER'S POCKET-BOOK.
1 lb. C converted to C02 yields 14,544 heat units.
About double the necessary air required in a direct fired fur- nace.
By the higher heats of regenerative furnaces Mr. Foulis increased the producing power of the works GO per cent.
One-half per cent, of free 0 in the waste gases may be considered good working.
The depth of fuel should be kept as regular as possible.
The use of tar as fuel causes difficulty in controlling furnaces, and regular and complete combustion.
The loss of gas from clay retorts in good working order is not at all important. (L. T. Wright.)
However hot the retort, an immediate and heavy fall in temperature must follow the introduction of the charge, to beVorked up again to its maximum in the allotted period. (A. F. Browne.)
4 per cent, air reduces the illuminating power 25 per cent.
1 per cent, of common air diminishes the illuminating power 6 per cent.
45 per cent, of air renders the gas non-illuminative.
1-inch back-pressure in retorts equals l-24th candle power lost.
The sulphur compounds are decomposed at a temperature of about 400° F.
In gas from wet coals the olefiant gas is reduced one-third.
Crude gas contains 4 per cent, by volume of gaseous impurities (H2S and C02 gas).
About 1 per cent, by volume of the crude gas is ammoniacal
About 3 per cent, by volume of the crude gas is C02.
About 1£ per cent, by volume of the crude gas is H2S.
Luting generally made of 2 parts clay to 1 part spent lime.
If the coke were drawn immediately it became incandescent, say about half-an-hour before the charge was done, much of the trouble with the sulphur compounds would be avoided.
High heats give a harder coke generally.
Gas coke contains C, N, S, H, and 0.
Coke contains about 88 per cent, carbon.
Coke when drawn from the retort and slaked contains about 25 per cent, moisture.
Coke averages 1,360 Ibs. per ton of coal, with about 4 per cent, ash in the coke. About 34 gallons Avater required to quench 1 ton coke, of which not more than GTlbs. water remains permanently in. the coke.
If steam be introduced along with the air into a coke-making plant, a larger percentage of ammonia can be extracted.
59 Ibs. slack coal required in furnaces to carbonize 2 cwt. coal.
41 Ibs. lump coal required in furnaces to carbonize 2 cwt. coal, say 570 Ibs. coal per ton.
In the petroleum-heated locomotives on the Great Eastern Kailway, a thin coal fire 6 inches thick (an ordinary one being 18 to 24 inches), mixed with lumps of chalk to keep the bars covered, is used so as to keep sufficient heat up, when stopping, to re-light the oil when re-starting.
LABOUR REQUIRED TO CARBONIZE.
245
Men Employed in Making say 3,000,000 Cubic Feet per Diem (Hand Charging).
Retort house work only, 17 (first-class) men, made up
s. d.
|
1 Foreman 20 (second-class) 10 (third-class) JV 7 Coal trimmers |
Men (stokers) !en (fire-rakers) . . . . |
7 5 4 4 |
<; 4 5 0 |
|
1 Pipe cleaner |
5 5 |
<) !l |
|
|
1 Flue cleaner 1 Lobby boy 1 Fitter |
|
5 3 , 5 |
(I (5 0 |
The above represents the number of men employed on each shift of eight hours.— (January 13th, 1893.)
Total Number of Men Required to Charge 240 Retorts with 240 Tons of Coal per Diem at Glasgow, Working 8-hour Shifts.
(A. Wilson.)
|
Manual Labour. |
Machine Work. |
|
|
60 Stokers |
6 Charging machine |
men |
|
15 Firemen |
6 Drawing machine men |
|
|
15 Ashmen |
15 Firemen |
|
|
30 Coalbreakers |
15 Ashmen |
|
|
10 Bogie drivers |
10 Coke men |
|
|
10 Coke men |
6 Pipe cleaners |
|
|
3 Water boys |
1 Lid cleaner |
|
|
3 Foremen |
6 Lid men |
|
|
146 men. |
3 Coal breaker men |
|
|
|
3 Locomotive boys |
|
|
Also 7 horses to draw out the coke. |
3 Shunters 3 Foremen |
|
|
77 men. |
Number of Men Employed on Furnaces (during 8 hours).
li firemen clean 2 fires and fill 4.
4 firemen in 24 hours attend 4 fires (cleaned every 6 hours). 1 fireman attends the equivalent of 6*01 fires (on the ordinary open double grate system).
Number of men employed on furnaces (during 8 hours) of 15 sets. " Buffalo Bill " settings (1 furnace to five sets). 1\ firemen clean 4 fires and feed from the top every 2 hours. 7 1 firemen in 24 hours attend 3 fires (fires cleaned every 6 hours),
246 GAS ENGINEER'S POCKET-BOOK.
1 fireman attends the equivalent of 12 fires (on the ordinary open double-grate system).
Each stoker may be made to handle an average of 4 ton coal per day.
Charging should be performed in rather less that one minute.
The air compressor at the South Metropolitan Gasworks used with the "West stoking machinery, shows a high duty, the mechanical efficiency is 80'3 per cent., the compression efficiency is 82-1 per cent., and the air delivery equals 369-3 cubic feet per I.H.P. per hour.
To Prevent Stopped Pipes they should be "kept cool, and light seals in the hydraulic maintained in liquor and not tar.
Space between ascension pipes and front wall of bench should not be less than 8 inches.
Water may be introduced at the top of the ascension pipe and allowed to trickle down the sides of the pipe.
Stopped pipes sometimes attributed to oscillation and pressure in the retorts from the dip and the exhauster.
Thick tar and soot and stopped ascension pipes are sometimes caused by porous parts in retorts, either new or recently cleared from carbon, which allow the gas to pass through and burn in the setting, while the soot and tar are carried up and deposited in the ascension pipe and hydraulic. The obvious cure is to paint the inside of the retort after such clearing of carbon and when new, with thin fire- clay mortar, and thus close the pores.
Suggestions for the Curing of Stopped Ascension Pipes.
Allow water to trickle down the interior from the top.
Place a bowl of water, or rag, or waste soaked in oil, small coal soaked in water, or pieces of solid grease, inside the retort, just below the bottom of the ascension pipe.
Keep open all doors, windows, or other available apertures.
Bring a supply of cold air, from outside, to the front of the bench by means of pipes.
Keep the retorts charged to their utmost capacity.
Lower the heats of the retorts ; this also clears" the hydraulic by causing oily tar to pass off from the coal.
Loss from stopped pipes has been known to exceed 10 per cent, of the gas to be obtained from the coal.
Stopped ascension pipes usually caused through excessive heat from setting. — To diminish the trouble, walls in front of benches should be 14 inches and not 0 inches thick.
Kapid radiation of heat and smooth interior surface, said to obviate stopped pipes.
To prevent stopped ascension pipes, leave the retort mouthpiece and the pipe open to the air.
The temperature of the pipes must be moderated by a supply of water which is led into them by a U-shaped tube screwed into their upper ends. The water drips into this tube from a supply above it. 63 to 70 ounces water per retort per hour required.
EFFECTS OF HEAT. 247
The gas in the ascension pipes is usually of a temperature of about 200* F.
Air circulating round the pipes and mouthpieces.
Water supplied internally or externally.
Liquor supplied internally or externally.
A lump of coal in the mouthpiece.
A handful of oily waste in the mouthpiece.
Animal fat in the mouthpiece.
Increase in length of rising pipe.
Plate or plates inside mouthpieces to prevent radiation of heat from inside retort.
Lining mouthpiece with fire-clay.
Air or water jacket to ascension pipe.
Carbon deposited in the retorts is generally increased by increase of pressure.
An oscillation caused by a badly working exhauster causes a greater deposit of carbon than a steady exhaust.
Pressure and oscillation are the chief causes of deposition of carbon.
The pressure on retorts is sometimes as high ;.s 15 inches water where an exhauster is not in use and the carbon deposit is then considerable.
The carbon deposited in the retorts consists of the richest illu- minants of the gas which have been solidified instead of carried forward in the gas.
If there be a heavy pressure in retorts some of the hydrocarbons are deposited as carbon in the retorts.
Under pressure some of the most valuable hydrocarbons are deposited in the retort as carbon or scurf.
The removal of the carbon from sloping retorts is easy, as the position of the latter causes a current of cool air to pass up when both doors are opened.
Carbon or scurf is removed by a chisel bar, or by allowing the oxygen of the air to burn the deposit until it is thin enough to remove easily ; this should be done about once a month.
The carbon in a retort being highly non-conducting, causes con- siderable waste of fuel, and should therefore never be allowed to get very thick.
Clay retorts are practically gas-tight up to about J-inch pressure.
To prevent carbon deposits, reduce the dip and the back pressure as much as possible.
Table of the Effects of Heat.
Degrees. Fahr.
Soft iron melts . . 3,945 Cast iron melts . . . 2,786 Gold melts . . . 2,016 Copper melts . . . 1,096 Silver „ 1.873
Bronze „ (copper
Degrees Fahr. Brass melts (copper 3 parts,
zinc 1 part) . . . 1,090 Brass melts (copper 2 parts,
zinc 2 parts) . . . 1,672 Diamond burns . . 1,552 Bronze melts (copper 7
parts, tin 1 part) . . 1,750 j parts, tin 1 part) . . 1,534
248
GAS ENGINEERS POCKET-BOOK.
Table of the Effects of Heat — continued.
|
Degrees. |
Degrees. |
|
|
Fahr. |
Fahr. |
|
|
Bronze melts (copper 3 |
Steel becomes a full yellow |
470 |
|
parts, tin 1 part) . . 1,440 |
Steel becomes a pale straw |
|
|
Enamel colours burn . . 1.892 |
colour . . . . |
450 |
|
Iron red hot in daylight . 1,272 |
Tin melts . |
442 |
|
Iron red hot in twilight . 884 |
Steel becomes a very faint |
|
|
Iron red hot in dark . 800 |
yellow . . . . |
430 |
|
Charcoal burns . . . 802 |
Tin 3 + lead 2 + bismuth |
|
|
Heat of a common fire . 790 |
1 melts |
334 |
|
Zinc melts . . . . 773 |
Tin and bismuth, equal |
|
|
Mercury boils . . . 6GO |
parts, melts . . . |
283 |
|
Linseed oil boils . . . G40 |
Sulphur melts . |
218 |
|
Lowest ignition of iron in |
Bismuth 5 + tin 3 + lead |
|
|
the dark . . . 635 |
2 melts . . . |
212 |
|
Water boils |
212 |
|
|
Steel becomes dark blue, |
Wax melts . . . . |
149 |
|
verging on black . . 600 |
Tallow melts . |
92 |
|
Steel becomes a full blue . 560 |
Acetic acid congeals . . |
50 |
|
Sulphur burns . . . 560 |
Olive oil congeals |
36 |
|
Steel becomes blue . . 550 |
Water freezes . . . |
32 |
|
Steel becomes purple . 530 |
Milk freezes |
30 |
|
Steel becomes brown, with |
Vinegar freezes . . . |
28 |
|
purple spots . . . 510 |
Sea water freezes |
28 |
|
Steel becomes brown . 490 |
Strong wine freezes . . |
20 |
|
Bismuth melts . . . 476 |
Turpentine freezes . |
14 |
|
Colours of Different Temperatures. (Becquerel.) |
||
|
Degrees. |
Degrees. |
|
|
Fahr. |
Fahr. |
|
|
Faint red . . . 960 |
White heat . . . . |
2,370 |
|
Dull red .... 1,290 |
Bright white heat . |
2,550 |
|
Brilliant red . . . 1,470 |
Brilliant white heat . . |
2,730 |
|
Cherry red . . . 1 650 |
Melting point of cast iron |
2,786 |
|
Bright cherry red . . 1,830 |
Welding heat . , . |
2,800 |
|
Orange .... 2,010 |
Greatest heat of iron blast |
|
|
Bright orange . . . 2,190 |
furnaces |
3,300 |
600° F. Faint red in dark room. 662° F. Mercury boils. 810° F. Antimony melts. 1,869° F. Brass melts.
1,873° F. Silver melts. 1,996° F. Copper melts. 2,786° F. Cast Iron melts.
Temperature of iron when red glow has disappeared, 404° C. It is said that no reliability can be placed on Wedgewood's pyro- meter.
PYROMETERS. 249
Pyrometers.
One part of zinc and 4 parts of copper melts at 1,050° C. ; 1 part of zinc and 6 parts of copper melts at 1,130° C. ; 1 part of zinc and 8 parts of copper, at 1,160° C. ; 1 part of zinc and 12 parts of copper, at 1,230° C. ; and 1 part of zinc and 20 parts of copper, at 1,300° C. The difficulty of getting pure metals to make these alloys, and of keeping them at the initial proportion, is against their use. The expansion of metals, clays, liquids and gases under heat is also used with varying success. The Lamy pyrometer, based on the decomposition of carbonate of lime under heat, is one of the best ; but it will only register between 700° and 900° C.
Herr C. Schneider proposes the use of nitrifiable test cones, con- taining silica 65 per cent., alumina S'3 per cent., ferric oxide 8*7 per cent., lime 10-6 per cent., and potash 7-6 per cent., or in vary- ing proportions, to test the heat of chambers with heats from 1,150° C. to 1,700° C. The greater the quantity of silica the more refractory the cone, the above mixture melting at 1,150° C. ; and by the substitution of 8 per cent, of boracic acid for the equivalent of silica the melting point equals 960° C. Or crystallized borax 193 parts, marble 50 parts, china clay 52 parts, sand 96 parts, will melt at 960° C.
Seger's standard fusible cones are used to determine the tempera- tures at which fusion occurs. These cones are tetrahedra, compounded of mixtures of clay and sand with certain fluxes. For temperatures from 1,300° to 1,700° F., soda and lead' oxide form the flux ; while boric acid is used for temperatures from 1,700° to 2,050° F. The same flux is used with gradually increasing proportions of alumina and silica up to 3,450° F. The last cones of the series, which are stated to fuse at temperatures from 3,500° to 3.950° F., consist of pure aluminium silicate.
Mr. P. Mahler's calorimeter consists of a shell or hollow cylindrical vessel, enclosed in another containing water at a known temperature. The shell being hermetically closed, pure oxygen, at a pressure of several atmospheres, is admitted, and the fuel fired by an electric spark, when the pressure of the compressed oxygen causes complete and almost instantaneous combustion. The heat generated is trans- mitted to the water surrounding the shell, the temperature of which rises immediately. Mr. Mahler uses only one grain of combustible. When gas is tested a vacuum must be produced in the shell before gas is admitted, and the quantity of oxygen necessary for com- bustion previously determined. Illuminating gas ignites with oxygen at a pressure of five atmospheres, producer gas requires a pressure of about half an atmosphere in the oxygen.
To Estimate Temperatures Roughly by the Appearance of Metal,
Degrees.
Fahr.
Red, just visible . 977 „ dull . . 1,290 „ cherry dull . 1,470 „ „ full . 1,650 „ „ clear 1,830
Degrees. Fahr.
Orange, deep . 2,010
., clear. . 2,190
White heat . . 2,370
„ bright . 2,550
„ dazzling . 2,730
250
GAS ENGINEERS POCKET-BOOK.
Temperature of Fusion.
Tallow . Spermaceti Wax, white Sulphur Tin
Bismuth . Lead . Zinc .
Degrees.
Fahr.
92
120
154
239 455 518 (530 793
Antimony . Brass . . . Silver, pure. Gold, coin . . Iron.cast,mcdium Steel . . . Wrought iron
Degrees. Fahr. 810 1.050 1.830 2.151) 2.010 2^550 2.910
Melting Points of Fusible Alloys.
|
Tin. |
Lead. |
Bis- muth. |
Degrees. Fahr. |
Tin. |
Lead. |
Bis- muth. |
Degrees. Fahr. |
|
2 |
3 |
5 |
199 |
8 |
15 |
_ |
430 |
|
1 |
1 |
4 |
201 |
1 |
2 |
|
440 |
|
3 |
2 |
5 |
212 |
8 |
17 |
|
450 |
|
4 |
1 |
5 |
24(5 |
4 |
10 |
|
470 |
|
1 |
1 |
1 |
255 |
1 |
3 |
|
480 |
|
2 |
2 |
1 |
292 |
4 |
14 |
|
490 |
|
3 |
3 |
1 |
310 |
8 |
33 |
|
500 |
|
4 |
4 |
1 |
320 |
1 |
5 |
. |
510 |
|
H |
1 |
— |
330 |
4 |
25 |
— |
520 |
|
2 |
1 |
— |
340 |
4 |
30 |
. |
530 |
|
4 |
1 |
|
3(55 |
1 |
10 |
. |
540 |
|
1 |
1 |
|
370 |
1 |
12 |
|
550 |
|
r> |
1 |
|
380 |
1 |
25 |
|
560 |
|
4 |
7 |
— |
420 |
An average sample of coal gives the following figures : —
Carbon (G) . Hydrogen (H) . Nitrogen (N) . Sulphur (S) Oxygen (0) . Ash ,
Percentage of coal in its use :-—
82-12 psr cant. 5-31 „
5-69 4-29
{Lancet.}
10.000 cubic feet gas =17 per cent. 10 gallons tar = 5-1 .,
Condensed liquor = 7*9 „ Ooke = 70
(Professor Lewes, 1894.)
RESIDUALS FROM COAL. 251
Approximate composition of bituminous coal : —
C 8OO per cent. 1ST 1-5 per cent.
H 50 „ 0 5-0
S 1-5 „ Ash 3-0
Moisture 4'0 per cent. Calorific value 8,020 thermal units. — (Professor Lewes.)
Cannel coal -specific gravity 1*1 to 1'4, organic matter consists of C = 70 to 85 per cent. ; 0 = 5 to 15 per cent. ; H = 5*5 to lO'O per cent. ; N = 1 to 2'5 per cent. : S = 0*5 to 2 '5 per cent. ; Ash 5 to 20 per cent.
Ash from average Newcastle coals :—
Silica GO
Peroxide of iron 16
Alumina ,12
Lime 10
Potash 1
Magnesia 1
2 to 4 gallons of water per ton is the average moisture in mechanical combination.
Laboratory tests of coals are generally 15 to 20 per cent, higher than actual working results.
About 16 gallons of water arc produced by carbonizing 1 ton coals. Gas made per ton Gas Light & Coke Co. £ year to December, 1892, 10,949 cubic feet.
Coke made '617 ton per ton. Breeze „ -OG4 ,,
C02 in crude gas . . . . 2' 5 to 3 per cent. H2S „ „ Ito2 „
CS2 is formed by the action of sulphur vapour upon red hot carbon.
Tar can be carbonized in ordinary clay retorts if allowed to run into the ascension pipe on to a fire clay tile fitted in the mouthpiece to prevent any accumulation of tar behind the lids, 40 gallons being burnt off in 6 hours. Iron retorts are however better. Tar conduit pipes should be large, say 2-inch.
Paper becomes charred at 400° P.
Table showing conversion of the elements of coal on carbonization
CO & C0
35-26 free in gas and in tar, 48-68 in coke.
252
GAS ENGINEER'S POCKET-BOOK.
A good gas coal should contain as large a percentage of H over and above that required to combine with the O as possible, and this should not be less than 4 per cent., while 5 per cent, will show a high quality coal. To obtain the quantity of H which will oxidize on carbonization divide the percentage of 0 by 8 and deduct the dividend from the percentage of H.
Total quantity of carbon in coal = 82 per cent. Gas contains „ „ = 16 „
Coke and tar „ '„ = 66 .,
Caking coal has specific gravity 1*25 to 1'35, and the organic matter in it consists of 80 to 90 per cent. C, 4-5 to 6 •() per cent. H, f> to 13 par cent. 0, and 1 to 2*5 per cent. N, average ash 7-5 per cent., sulphur 0-5 to 2-5 per cent. (Butterfield.)
|
Lancashire Coal. |
Newcastle Coal. |
Welsh Coal. |
Scotch Coal. |
|
|
C per cent. |
80-70 |
83-60 |
86-26 |
78-50 |
|
H |
5-50 |
5-28 |
4-66 |
8-33 |
|
O |
8-48 |
4-65 |
2-60 |
8.33 |
|
N |
1-12 |
1-22 |
1-45 |
1-14 |
|
s |
1-50 |
1-25 |
1-77 |
1-45 |
|
Ash ., |
2-70 |
4-00 |
3-26 |
4-00 |
Coal contains from 50 to 80 per cent, by weight, of carbon.
Average composition 80 per cent. C, 5 per cent. H, 8 per cent. 0. 4 per cent, ash, 1£ per cent. S, li per cent. N. Coke equals <>1 per cant., specific gravity equals 1-279, weight per cubic foot equals 80 Ibs. Bituminous coal contains from 6 to 10 per cent, water.
In most Tars there are 40 per cent, of compounds capable of conversion into illuminating gases.
An ordinary sample of tar will yield at least 10,000 cubic feet of 15 candle gas per ton of 200 gallons, with coke, free from ash, weigh- ing about 10 cwt., and if produced at proper temperatures equal to foundry coke, ammonia equal to the production of 16 Ibs. sulphate per ton of tar.
The theory of the tar process as used at Widnes is that a fresh charge of coal cools the retort for a time, during which a considerable quantity of tarry vapours are being given off from the coals, and these tarry vapours are carried along the duct, as the second retort is called, and there gasified into permanent gases instead of being deposited in the condenser mains as tar.
The volume of Gas from Wood Charcoal amounts to 250 litres per kilogramme, and, when prepared on a large scale, it contains C02 9-14 per cent., CO 18-08 per cent., H 49-11 per cent., CH^ 16-04 per cent., O 0'26 per cent., N 7'37 per cent. (Comptes Rendus.)
Wood Gas gives about 8,000 cubic feet per ton of poor gas.
Mr. W. King, of Liverpool, found that the average yield per ton of tar thoroughly dried at 212° F. before carbonization was 12,000 cubic
GAS FROM DIFFERENT SUBSTANCES. 253
feet ot 4-candlc gas, 5£ cwt. charcoal (worthless for fuel). 33 per cent. CO, and very little tar.
By the Dinsmore process, following a coal gas carbonization, afoout 10,000 cubic feet per ton of 19-canclle gas are obtained from a poor coal.
One Ton Split Wood yields 11,000 cubic feet per ton of 16 ' candles, with 4 cwts. charcoal, and 1 to l^cwts. of tar, with a large quantity of C02 (9 to 18 per cent.).
Cork refuse made 18,000 cubic feet gas per ton of good quality and purity. (X. II. Humphrey.)
Pine Wood Sawdust carbonized at 1,500° F. yields 12,300 to 15,700 cubic feet per ton of dried material of 15 candles (specific gravity •500 to -620), and contains about 7'5 per cent, illuminants, 33 per cent. H, 27 per cent. CH4, 32 per cent. CO.
Peat perfectly dried and compressed yields at red heat 11,000 cubic feet per ton of 17 to 18 candle gas with 9 cwts. coke, 15 gals, tar, and a quantity of ammonia. (Butterfield.)
High heats, light charges, and plenty of red-hot surface have been found the best when carbonizing wood for gas-making purpose?.
Gas made from Resin is said to deposit a viscid matter in pipes and fittings.
The tar should be removed as soon as its temperature is down to 100° to 110° F.
Gas washed with the heavier hydrocarbons, as in a tar seal in a hydraulic main, absorbs a number of the lighter hydrocarbons which would otherwise remain in the gas and give it a higher illuminating power.
If too much tar is allowed to remain in the hydraulic main, tho heat of the incoming gas gradually boils off the lighter oils and causes the formation of pitch.
The gas which enters the hydraulic main from the ascension pipe, carries with it a number of hydrocarbon vapours, condensing at from 140° to 160° F.
Mr. L. T. Wright proposed to run in water to keep the temperature of the hydraulic main at about 100° F., and thereby reduce the quantity of impurities in the gas.
The lighter hydrocarbons which condense at temperatures above 100° F.. do not' injure the illuminating power of the gas, and may absorb any excess of napthalene. (Herring.)
If a hot liquid is used in the hydraulic mains, weak ammoniacal liquor would be likely to liberate its ammonia, and increase the amount of that impurity to be removed later on.
Gas as it leaves the retorts is enveloped in very minute tarry vesicles which require friction to break them up.
Gas on leaving the dip-pipe should pass through water and not tar.
Liquor may be run in to replace tar in hydraulic twice a day.
Hydraulic main tar will, at 130° F.. dissolve upwards of 70 per cent, of napthalene, so that it will be seen what a powerful factor in re- moving this is eliminated by using liquor seals in the hydraulic mains.
The liquor in the hydraulic main consists of sulphocyanide and hyposulphate of ammonia, also some carbonate and sulphide.
254 GAS ENGINEER'S POCKET-BOOK.
Anti-dip-pipes should be worked so that there is a pressure in the retorts, and then no deleterious gases are drawn in through cracks in the retorts.
Mr. Gandon found an increase of 300 to 400 feet per ton with anti- dip pipes.
At outlet of hydraulic main *3 to '5 cf the condensable constituents are deposited. (Professor Wanklyn.)
Half to one- third the condensable vapours are deposited in the hydraulic mains.
Crude gas contains about 143 grains ammonia per 100 cubic feet, 2-95 per cent. H2S., 2-04 per cent. C02.
In the hydraulic main, for every 100 volumes free ammonia there are about 24 volumes C00 and 11 volumes H0S.
Temperatures found in Ascension Pipe. (\V. Foulis.)
18 Inches from 12 Feet from 22 Feet from
Mouthpiece. Mouthpiece. Mouthpiece.
890° to 518° F. 444° to 167° F. 240° to 144° F.
Temperature in retort, 18 inches from mouthpiece, 1 ,1 10° to 1,G40° F.
Temperatures fell as above during charge, always getting lower as charge was worked off. Gas made equalled 10,000 cubic feet per ton.
If only 6.000 cubic feet per ton were being made, temperature, at 18 inches from mouthpiece, in ascension pipe would probably be only 400° to 500° F.
Temperature of gas leaving hydraulic main, 50° to 60° C.}or 110° to 150° F.
Temperature of gas weaving condenser, 15-5° C.
Temperature of foul main averages about 110° F. to 138° F.
Usually considered, the temperature of gas in leaving the retort 2quais 2CO° to 300° F.. but unless it is as high as 480° F. thickening of the tar in the hydraulic, and choking of the ascension pipe will certainly occur.
The gas leaving a retort freely has only a temperature of 220° to 830° F., owing to the great absorption of heat on its assuming a gaseous form.
Temperature of gas 3 feet above mouthpiece 150° to 170° F. ; 17 feet from mouthpiece 120° to 136° F.
M. Euchene gives (1900) chimney gases, ordinary retorts, 1,787° F. Temperature in gas in retort, at first 1,166° F., at end of charge 1,355° F., average 1.260° F., but as the volatile products come off early, average taken as 1,202° F. Temperature in retort mouthpiece from 788° F. to 824° F. Temperature in hydraulic main 176° F. Temperature in charge in retort 932° F. in first half-hour, rising to 1,740° F. during distillation,
CONDENSING GAS. 255
CONDENSING.
The Products of one Ton of Newcastle Coal after Carbonization are: —
Lbs. Per Cent.
10,000 cubic feet of gas . . 380 . . 17'0
10 gallons of tar . . . . 115 . . . 5'1
Virgin gas liquor . . . . 177 . .7-9
Coke 1,568 . . . 70-0
2,240 100-0
One ton of coal yields 5 per cent, weight of tar (approximately). (Wanklyn.)
About 8 feet of H2S is contained per 1,000 cubic feet of Newcastle coal gas.
About 25 cubic feet of C02 is contained per 1,000 cubic feet of Newcastle coal gas.
7 to 12 per cent. CO is present in coal gas.
CO has a greater diluting effect than H.
H has a greater diluting effect than marsh gas.
10 to 13 gallons tar, and 13 to 30 gallons water are deposited by the time the gas reaches the outlet of the condensers.
The idea which some engineers had of leaving the gas with the tar as long as possible was, that they believed the latter absorbed C02 and H2S, but the quantity of rich hydrocarbons also absorbed was not taken into account.
Doing away with the condenser at Richmond practically raised the illuminating power of the gas f candle. (T. May.)
If gas be condensed below 45° F. the illuminating power is reduced, extreme cold having a detrimental effect on the illuminating power.
The tar should be removed from the gas as soon as possible until the latter has been cooled to about 105° F.
If the heavy tar oils and pitch are allowed to continue with the gas which is above 90° F. they absorb hydrocarbons from the gas.
The gas enters the condenser main at about 122° F.
The temperature of the gas should be gradually reduced to 90° F. before it enters the condensers.
Condensation is required to remove all the tarry vesicles, and if this be done the temperature of the gas may be left to take care of itself as it will be cooled later on to atmospheric temperature.
The condensers are best kept at the normal temperature of the air. If above or below this, the action of the purifier is interfered with.
Much inconvenience in scrubbers and washers may be avoided by arranging condensers so that the gas is not cooled excessively.
If the gas is not properly condensed before it enters the scrubbers the efficiency of the latter will be impaired.
The richer the gas the greater the loss of hydrocarbons by exposure to low temperature.
256 GAS ENGINEER'S POCKET-BOOK.
When the condensation is carried below GU° F., and friction is made to take place napthalene is frequently deposited.
It is better to have napthalene in the works than in the district.
Napthalene deposition in the works can be prevented by the use of liquor seals in place of tar, by quickly removing the tar from contact with the gas, and by long condensing or foul mains.
Keeping up the temperature at outlet of condensers to 60° to 75° F. will prevent the deposition of napthalene at that point, but may send it into the district.
It has been suggested to keep the temperature of the tar and liquor in the hydraulic main at about 100° F. so that the tar may retain a portion of the napthalene and bi-sulphide of carbon which it will not do at 1GO° F.
If gas is thoroughly dried no napthalene is deposited..
One method of clearing the napthalene from condensers is to run a small stream of liquor periodically into the first three or four compartments.
Poor gas may tend to the deposition of napthalene as certain hydrocarbons have the power of carrying others of different specific gravity.
A sudden cooling of the gas causes deposits of hydrocarbons and napthalene.
Napthalene fuses at 176° F., boils at 123° F., is not soluble in water.
To cure this trouble avoid wet coal — keep your heats as even as "le.
Tests for Napthalene.
Dilute ammoniacal liquor with sulphuric acid, and if napthalene be present it becomes rose colour and smells of napthalene.
Redden liquor with nitric acid super-saturated with muriatic acid. If napthalene be present it will tinge a piece of finvood a rich purple.
In order to dissolve napthalene in the condensers, Mr. Carpenter arranged a condenser to be reversible. When the outlet became partly choked it was made the inlet. The tarry vapours of the hot gas dissolved the deposit, which was quickly run off by the seals.
The liquor from the condensers contains sulphocyanide, sulphate and hyposulphite among the fixed salts of ammonia.
Analysis of Crude Gas leaving- Condensers. (Butter field.)
NH3 0-05 to 0-95 per cent, by volumes.
C00 1-2 „ 1-8
H2S 0-9 „ 1-5 „
CS2 0-020 ,, 0-035 „
Cyanogen 0'05 '., O'lO „
TESTS OF GAS AFTER CONDENSERS.
257
Analysis of Crude Gas Leaving Condensers, (Professor Wanklyn at South Metropolitan Gas Co., Old Kent Road.)
In 1000 volumes SH0 equals „ „ C02 equals .
„ „ NH3 equals
12'1 volumes, 15 3-6
Impurities in Condensed but Unwashed Gas, (Lewis T. Wright.)
|
C0a |
HaS |
|||
|
Grains per Cubic Foot. |
Volume per Cent. |
Grains per Cubic Foot. |
Volume per Cent. |
|
|
Newcastle Yorkshire Silkstone Derbyshire ,, Cannels . |
12 12 12 to 19 30 |
1-5 1-5 1-5 to 2-3 3-7 |
9 8 G to 12 3 to G |
1-3 1 to 2-0 0-5 to 1-0 |
Tar made per ton, Gas Light and Coke. Co., half-year to December, 1892,10-58 gallons.
Average Analysis of Gas (Newcastle Coal) after Condensers.
|
H ... Methane . . . Carbon Monoxide . Hydrocarbons light C02 . . . . |
47 per cent. 35 „ 5 3-5 i-o 1-5 ,, |
N H2S NH3 . Cyanogen CSfl . |
. 3-0 per cent. . . 1-7 „ . . 0-7 „ . . 0-1 „ . . 0-03 „ |
(Butterfield.)
GE.
258 GAS ENGINEER'S POCKET-BOOK
EXHATJSTEKS, ETC.
By exhausting at 120° F., and passing gas direct to the scrubbers, an increase of from *5 to *7o candle resulted at Croydon. To relieve the consequent back pressure in scrubbers, warm water was tried, but nearly double the water was required to remove the ammonia from the gas.
When byepassing the condenser the exhauster frequently becomes choked with sticky tar.
Temperature of gas at exhauster usually 110° to 120° F. without condensers giving 110° F. at inlet of condenser.
Increase of pressure raises the inflammability of gaseous mixtures having a combustible gas as one of their ingredients.
One of the evils of over-exhausting is the admission of furnace gases with the coal gas, and the consequent deterioration of the illuminating power of the latter ; another is the increase of fixed ammonia and reduction of free ammonia by the admission of air or furnace gases.
1 per cent, air has no effect on illuminating power.
2£ per cent, air lowered 17-candle gas to 13'45 candles at Ramsgate.
8 „ „ „ „ 13-04
5 „ ,, „ „ 10-59
Use Creosote Oil as a Lubricant for foul gas exhausters (Mr. Bacon, of B. Donkin & Co.). It is also said that castor oil forms the best lubricant for exhauster, and should have specific gravity *9GO ; if below -955 it is impure. Another test of purity consists in adding zinc chloride, and then, if pure, the oil will turn yellow.
Sperm oil may also be tested with zinc chloride, but this, if pure, turns milky.
For lubrication of the working parts of the exhauster, a mixture of pure colza, tar, oil, and naptha has been found the best for the purpose.
In the use of -oil for lubrication uniformity of distribution is as important as the regularity of supply. A dry spot on a bearing will at once cause heating, and, if allowed to continue, cutting will be the result. No oil has yet been made that can economically lubricate all the journals of a mill. An oil running a heavy engine would not do to run a spindle or a fast-revolving dynamo. The former runs slowly, and has great pressure and strain on its journals, and consequently requires an oil that will not spread too quickly, but with low gravity and high viscosity. The latter needs a pure mineral oil, viscous and quick spreading, to enable it to enter into the closest parts of the bearing as rapidly as the speed at which it revolves necessitates. Mineral lubricants, or compounds of mineral and animal, are the safest, and produce the best results. Professor Thurston says, " Rancid oil will attack and injure machinery. Mineral oil does not absorb oxygen, whether alone or in contact with cotton waste, and cannot, therefore, take fire spontaneously ; animal and vegetable oils do. Mineral lubricating oils are used on all kinds of machinery : they are the safest and cheapest lubricants, and generally superior to
COMBUSTION OP FUELS.
259
animal and vegetable oils and greases." A mineral oil flashing below 300° is unsafe. Gumming is due to the action of free acid upon the metal bearings of machinery. J. J. Redwood remarks, " Mineral oil has the least action on metals, none on iron or brass ; tallow oil has most action on iron ; castor, olive, and lard oils have most action on brass ; rape seed has most action on copper."
Heat of Combustion of Various Fuels.
|
Substance. |
Average Ht>at fron, 1 Ib. Fuel. Thermal Units. |
Equivalent Evaporation from and at 212° F. per Ib. of Fuel, in Ibs. Water. |
|
Carbon (pure) .... Coal gas Coal gas, per cubic foot, at 62° F. Coal, good average quality . Coke |
14,560 17,800 630 14,700 13,500 62000 |
15-07 18-43 0-70 15-22 13-87 64-20 |
|
Peat (dessicatcd) . . . . Peat, 25 per cent, moisture . Petroleum oils (benzine, etc.) Petroleum crude .... Petroleum refuse, " astaki " . . Straw Sulphur "Wood, air dried .... Wood, dessicated . . . Wood, charcoal dessicated . |
10,000 7,000 27,500 • 20,400 20,000 8,000 4,000 8.000 niooo 13,000 |
10-35 7-25 28-56 21-13 20-70 8-40 4-14 8-28 11-39 13-46 |
Theoretically, 11 Ibs. air is required per 1 Ib. coal to supply the necessary oxygen ; practically, 22 Ibs. air is required. 1 Ib. coke evaporates about 9 Ibs. water. 1 Ib. „ „ „ |th cubic foot water.
1 Ib. coal „ „ 9 Ibs. water.
1 Ib. slack „ „ 4 Ibs. „
Pounds of Water Evaporated per Ib. of Fuel. (B. Donkin & Co.)
Breeze or dust gas coke as burnt on Perret's grate, 5£ Ibs. water. Dust Welsh coal „ „ „ 8£ „
Ordinary Welsh coal on ordinary grate . . 9 Large gas coke „ „ . . 7£ „
Another authority gives : —
Lbs. of water evaporated at 212° per Ib. of fuel. 7'4 Ibs. per Ib. breeze. 7-5 Ibs. per Ib. coke. 11-4 Ibs. per Ib. Welsh coal.
P2
260
GAS ENGINEER'S POCKET-BOOK,
Relative Heating Power of Fuel. (Fritz.)
|
Lbs. of Water Evaporated by |
|||
|
1 Ib. of Fuel. |
|||
|
Fuel. |
Theoretical. |
In Steam Boilers. |
In Open Boilers. |
|
Anthracite |
12-40 |
|
|
|
Coal |
11-51 |
5-2 to 8 |
5-2 |
|
Charcoal .... |
10-77 |
6 , 6-75 |
3-7 |
|
Coke |
9 to 10-8 |
5 , 8 |
|
|
Brown Coal . |
7'7 |
2-2 , 5-5 |
1-5 to 2-3 |
|
Peat |
5-5 to 7-4 |
2-5 . 4-5 |
1-7 „ 2-3 |
|
Wood .... |
4-3 to 5-6 |
2-5 , 3-75 |
1-85 ., 2-1 |
|
Straw . . . . |
3-0 |
1-80 , 1-93 |
|
|
Gas reduced to Ibs. coal . |
— |
4 . G |
— |
In heating boilers the average amount of theoretical heating power of fuel that is utilised is only 47 per cent., the remainder being lost through imperfect combustion, radiation, and other causes.
Evaporative Power of Fuel.
Another set of tests gave : —
1 Ib. coke evaporates 9 Ibs. water (feed water supplied at 212°F.). 1 „ coal „ 9 „
1 „ slack „ 4 „ 1 „ oak (dry) „ 4£ „ 1 „ pine „ 2£ „
An average of 27 coals for fuel measured about 40£ cubic feet per ton.
Cost of evaporating 10 Ibs. of water from steam boilers. Breeze at 4/6 per ton = 0-03f>d. Coke at 12/- per ton = 0'097tf.
Welsh coal at 20/- per ton = 0-l07d.
Coke and coal are usually considered of equal calorific value, weight for weight.
Boiler should be fed by small quantities and often, so that the draught of the chimney does not carry away the fuel improperly c bined to form a permanent invisible gas ; smoke is only the condensing of gases that having been liberated by heat, have been allowed to cool back again and lapse back to their constituent parts before chemical union has arranged their molecules so as to render them invisible, when they enter the atmosphere and become absorbed in it
Andrew's patent fuel for boilers and retort furnaces consists of 40 gallons tar to I chaldron (21£ cwt.) breeze, and sets hard in a few days.
com- re-
BOILER INCRUSTATIONS. 261
Average Water Consumption in Steam Engines.
Non-condensing . . 25 to 40 Ibs. per I.H.P. per hour. Condensing . . . 18 „ 30 „ „ „
Compound . . .1(5 ,, 20 ., „ .,
Triple expansion . . 13£ „ 15 „ „ „
Heat feed water of boilers to 212° F. if possible. The usual course adopted by the engine and boiler minders is to inject tallow into the boiler to prevent priming.
To Prevent Boiler Incrustations.
Two ounces muriate of ammonia in boiler twice a week.
Carbonate of soda.
Frequent blowing off.
Any fatty deposit on the interior surface of a boiler-plate greatly hinders the transmission of heat. (J. Kirsh.)
Use caustic soda and soda ash for prevention of depositions of carbonate and sulphate of lime in boilers. 1£ ounces pure caustic soda per 1.000 gallons for each grain carbonate of lime in feed water, and 1:| ounces carbonate of soda (soda ash) per 1,000 per grain.
Remove all sediment from boiler through blow-off cock every twelve hours.
Ordinary feed water may be said to contain '05 per cent, solid matter, or 35 grains per gallon (in a boiler of 100 H.P. this equals 1 Ib. solid matter deposited per hour). By heating the feed water a large proportion of this may be kept out of the boilers.
Carbonates of lime and magnesia are deposited slowly at 150° F., but at from 280° to 300° the deposition is rapid (except 2 or 3 grains per gallon, which remains dissolved).
Sulphate of lime is deposited at 307°.
11 Ibs. air required theoretically for 1 Ib. coal burnt, but double this necessary with natural draught in boilers.
The proportion of carbonic acid gas in the boiler flue should lie between 1 1 per cent, with bituminous and 15 per cent, with anthracite coals, with a small percentage of oxygen and no carbonic oxide.
Heat at outlet of chimney may be reduced to 300° C. without injury to draught.
When a jet photometer is fixed in the exhauster house, the gas should be purified by means of small lime and oxide purifiers before admission to the photometer.
262 GAS ENGINEER'S POCKET-BOOK.
WASHING AND SCRUBBING.
Gas should be free from tar before it enters the washers and scrubbers, or the efficient working of the latter will be impaired.
Clean water scrubbers require from 2 to 3 gallons water per 1 .000 cubic feet of gas passed through them.
Quantity of water required in standard washer scrubber 10 gallons per ton. This removed 241 grains NH3 and reduced the C00 and H2S some 30 per cent. ; 50 square feet of wetted surface is exposed to the gas per cubic foot of machine.
13-7 gallons of water used in Kirkham Hulett and Chandler's washers per ton of coal carbonized and liquor produced was of 15 ounces strength. (King's Cross Works, 1881.)
Water at ordinary temperature absorbs 700 times its volume of ammonia gas.
Cold water will absorb about 1,000 times its bulk of ammonia gas.
Water in scrubbers should not be lower than 50° or hydrocarbons will be deposited.
At a temperature of GO0 F. liquor of 14 ounces strength cannot reduce the ammonia in the gas it is in contact with to a lower degree than 54 grains per 100 cubic feet. (L. T. Wright.)
At a temperature of 183° F. water will not absorb ammonia.
Where there is plenty of washing and scrubbing room, water at 70° F. has been used and good results obtained.
If the water used to abstract ammonia is warm it wHl afterwards freely give off ammonia into the air.
The water used in scrubbing has a distinctly deteriorative action on the illuminating power of the gas.
If gas be lowered in temperature below 40° F. it has to be raised in scrubbers, and napthalene will be deposited in them.
Average yield of ammonia per ton equals 6'8 Ibs., or To percent, by volume, or 467 grains per 100 cubic feet at outlet from retorts.
About one-half of the total ammonia in the gas is removed by the scrubbers.
NHg removed by condensation . . . 42'7 per cent. NH8 „ first scrubber . . . 43-3 „
KH8 „ second „ . . .14-0 „
(C. Hunt.)
Ammonia is produced in a greater amount during the earlier period of the charge, and cyanogen during the latter hours.
Lancashire and Yorkshire coal generally contains a larger propor- tion of ammonia than Durham coal.
The ammonia in Midland Counties coal varies from 62-7 to 141-2 ounces per ton.
Equal and thorough wetting of the material in the scrubber is necessary to ensure good working.
With tower scrubbers extreme cold may have a detrimental effect on the illuminating power.
SCRUBBING.
.About 26 to 36 gallons of 10 ounce liquor are produced per ton of coal.
If gas be passed through a coke or clinker-filled scrubber, saturated with tar. it will injure the gas by as much as 2 candles.
A lead-lined scrubber containing weak acid might be used for the elimination of the last few grains of ammonia, and thus water be saved.
If liquor which has once passed through a scrubber be purified partly from H2S and C02, it can be made to removo nearly all the H0S and much of the CO2 when used again in the scrubber.
In ammoniacal liquor, £ths of the ammonia is combined with CO2 and H0S and can be freecl by boiling, the remaining ith is combined with hydrochloric, sulphuric, and other acids which cannot be freed by boiling.
1000 cubic feet crude Newcastle coal gas contains about 8 cubic feet H2S, 25 cubic feet C0a.
About eight times the ammonia present in the crude gas would be required to eliminate all the CO2 and H2S in the gas.
A strong solution of ammoniacal liquor is required to effectually remove as large a proportion as possible of the H2S and C0a from the gas in the washers.
Of the total volume of ammonia in the gas there will be 1*2 per cent, available for combining with the C02 and the hydro-sulphuric acids which will be able to remove O'G per cent, of C00 and 0'18 per cent, H2S.
One combining equivalent NH3 will -absorb CO, or H2S to the extent of 1 J to 1 1 combining equivalent of one or both of these acid bodies. (Butterfield.)
100 volumes NH3 combine with about 12£ volumes H2S.
100 volumes NH3 combine with about 50 volumes C02.
In a washer using 7 ounce liquor which thus became one of 14 ounce strength, the latter was found to contain 5,000 cubic inches of CO2and H2S equal to 357 cubic inches per ounce of strength, and the cost of dry purification by the dry process was reduced by 20 per cent.
Maximum tension of ammonia gas in coal gas is about 0'45 inches mercury.
When the quantity of water is reduced owing to smaller makes, the impurities in the gas travel further forward in the apparatus before being removed from the gas.
Scrubbers remove about 2 grains CS2 per 100 cubic feet.
Ammoniacal liquor will remove ammonia from the gas in propor- tion to its own strength of ammonia only, therefore too strong ammonia used over the first scrubber may have the effect of increas- ing the quantity of the ammonia in the gas if the amount present before the gas enters the scrubber is less than the equivalent quantity in the liquor being used for washing purposes.
In gas liquor of average strength there is generally from GO to 70 per cent, by volume of carbonic and hydro -sulphuric acid in pro- portion to the volume of ammonia.
1 gallon 10 ounce liquor contains 4,704 cubic inches C02 and 1,362 cubic inches H2S, with 6.066 cubic inches other foul gases or equal to 57 cubic feet C02, 16 cubic feet HaS. (G. Livesey.)
1 cubic foot NH8 = 316-77 grs.
GAS ENGINEER'S POCKET-BOOK.
The ino3t probable proportion of ammonia to C02 in gas liquor would be 2 volumes NH3 to 1 volume C02, but with NH3 and H2S, 1 of NH3 to 1 of H2S'is more likely.
Ammonia combines with CO3 to form ammonium bicarbonate (NH4HC03).
Ammonia combines with H0S to form ammonium sulphohydratc (NH4HS) ; or,
Ammonia combines with C00 to form ammonium monocarbonate (NH4)3C03.
Ammonia combines with H2S to form ammonium sulphide.
Ammoniacal liquor is a weak solution of ammonium bicarbonate (NH4HC03), ammonium sulpho-hydrate (NH4HS), together with appreciable quantities of sulpho-cyanide (NH4CNS) and thio-sulphate
Analysis of Ammoniacal Liquor. (Professor Lewes.)
s?
Free
Ammonia sulphide
„ carbonate
., chloride
., thio-cyanate
., sulphate i- Fixed
., thio-sulphate i
., ferro- cyanide]
Grammes per Litre. 3-03
39-16
14-23 1-80 0-19 2-80 0-41
Water will dissolve at GO0 F. and 30 inches barometer, an equal volume of C02.
Water will dissolve at 32° F. If volume of C02.
Water will dissolve at 23° F. 4-37 volumes of H0S, and '001 volume of CS2.
Water will dissolve at 60° F. and 30 inches barometer 783 volumes of NH3.
Water will dissolve at 183° F. no NH3.
1° Twaddel equals about two ounces strength by distillation.
Factor for Rendering Degrees Twaddel into Ounces Strength. (Lewis T. Wright.)
|
Description of Liquor. |
Saturation. |
Distillation. |
|
Natural ., . • . . „ cannel coal . Final product . . . |
2-18 1-80 1-68 1-G2 1*68 |
2-54 2-43 2-22 2-00 2-04 |
|
1-59 |
1-92 |
|
|
From clean water scrubbers |
1-64 to 1-83 |
CYANOGEN. 265
Hill's process of u ammonia purification" consists of bringing the liquor, after use in the scrubbers, to nearly boiling point, when the C02 and H2S are driven off and the ammonia can then be used again in the scrubbers for the further elimination of C02 and H2S.
Caking coals contain from 1*56 to 1'9 per cent. N, but of this amount only 11 '59 to 15'72 per cent, comes off as NH3 during distillation.
Yield of ammonia greatest at medium heats. (L. T. Wright.)
Of the total N in the coal, 14'5 per cent, passes off as ammonia, 1'56 per cent, as cyanogen, -tS'68 per cent, in coke, 35'26 per cent, in the gas. (Professor W. Foster.)
Tlae greater the proportion of fixed ammonia the less the purifying power of the liquor for the elimination of H2S or C02.
The liquor from the scrubbers contains carbonate and sulphide of ammonium, some free alkali and sulphocyanide, hyposulphite and sulphate.
If sufficient ammonia be presented to the crude gas all the H2S, C02, and CS2 will be removed.
If liquor could be made to give off the H2S and C02 which it has taken up in the scrubbers arid could be "used over again these impurities might be removed almost entirely by the ammonia.
By Hill's process the liquor was heated to 180° F., when the 000 and H.,S were driven off as follows:— NH.HCO, = NH, + H20 4- C02, arid NH.HS = NH3 + II2S.
To prevent the loss of ammonia the gases were passed through a scrubber supplied with liquor at 160° F. which it was supposed would arrest any ammonia gases. To obtain sufficient ammonia to remove all the C02 from the crude gas, the liquor has to ba treated twice for the removal of the C03 previously taken up.
Cyanogen. — The quantity of cyanogen recoverable from coal gas varies with the temperature of carbonization, from 5,000 grains with low heats to 10,000 grains with high heats per ton of coal.
The most favourable temperature in the retorts for the formation of cyanides equals 2,200° F.
Cyanogen is the gaseous compound of carbon and nitrogen,
To Recover the Cyanogen,
First remove all the NH3 and then pass the gas through soda or potash in solution in presence of an iron salt, when from -t to 4.J Ibs. of crystallized ferrocyanide of soda or potash is recoverable per ton of coal.
Spent products in gas works rarely contain more than 15 per cent, of ferrocyanide of potassium. (M. Perthuis.)
Ammoniacal liquor made per ton, Gas Light and Coke Co. half year to December, 1892 :— -279 butts per ton of 10 ounce strength by distillation,
2G6 GAS ENGINEER'S POCKET-BOOK.
Impurities in Coal Gas after passing Scrubbers. (Butterfield.)
H S 500 to 800 grains^
C02 700 to 1,100 „ per 100 cubic feet.
CSa 30 to 45 ., j
Average Composition of Gas after leaving Scrubbers. (Professor V. B. Lewes.)
H 48*55 per cent, by volume.
Methane 39'70
Illuminants 3'30 ., „
co2 2-50 ;, ;,
CO 2-00 „ .,
O 0-45
N 3-50 ., „
If the scrubbing is properly done, the gas should not contain more than 1-4 per cent. CO,, 0'3 per cent. H2S, and from 38 to 42 grains CSa per 100 cubic feet with no ammonia.
Gas after leaving scrubbers contains about 400 grains H2S and 35 to 40 grains CS, and other sulphur compounds.
PURIFICATION. 267
PURIFYING.
Gas loses about 3 per cent, by volume in passing through the purifiers, due to the elimination of the C02 (2-25 per cent.) and H2S (0-75 per cent,).
25 cubic feet of CO., per 1,000 cubic feet gas reduces illuminating power about two candles, or, in other words, 1 per cent. C0a diminishes illuminating power 7 per cent.
CO is present in coal gas to the extent of from 3 to 8 per cent.
I'l per cent. S in coal equals 1*2 per cent, of H0S in the gas.
(Butterfield.)
Crude gas contains about 8 feet of sulphuretted hydrogen per 1 .000 feet of gas from Newcastle coal.
Sulphuretted hydrogen is 1 part H, lf> parts S ; specific gravity is T178 ; 100 cubic inches weigh 36'51 grains.
In ordinary use a purifier is turned off before it has ceased to remove H2S, the usual test being that the next box shows a foul test.
Oxide of iron will at times absorb CS2. but will again give this off quite suddenly, possibly owing to the affinity of S for CS2, which can be disturbed by a slight increase in temperature.
If gas containing CS2 is passed through a mixture of sawdust and sulphur the quantity of" CS2 will be reduced 50 per cent.
Oxide of iron, after fouling, contains some free sulphur and iron sulphide ; and revivification converts this into sulphur and hydra ted iron oxide by the action of moisture and air.
Analysis of Bog Ore (Dry basis).
Ferric oxide 60 to 70 per cent.
Organic matter 15 to 25 .,
Silica 4 to 6 „
Alumina 1 ,,
When in use the material would contain about 30 to 40 per cent. water. Bog ore is a hydratcd sesquioxide of iron (Fe2, 03, 3 HS0).
Composition of Bog Ore : —
H30 50 per cent.
Hydrated oxide of iron, active . 20) «9
„ inactive . 12 } *
Vegetable matter . . . . . . 18 ,,
Bog ore when ready to place in purifier should only contain 25 per cent, moisture.
Westbury Natural Oxide contains about —
66 per cent, hydrated peroxide of iron, 28 „ earthy matter, 6 „ uncombined water.
(N. H. Humphreys.)
Bog ore contains 30 per cent, Fe2, 03, and 55 per cent, moisture.
268
Analysis of O'Neill's Oxide. (Jane. 1875.)
Water per cent 22-30
Fibre ll'GO
Peroxide of iron 65-42
Silica -57
Loss . '11
100-00
One cubic foot of oxide weighs 56 Ibs.
" One ton of oxide should eliminate the H2S from 3.000.000 cubic feet of Newcastle coal gas, which contains about 8 cubic feet of H_S."
" An average quantity of oxide for 2,000,000 cubic feet of gas is one ton when oxide only is used."
" One ton bog ore should purify from 1,250.000 to 1,500,000 cubic feet of gas from H2S before becoming spent."
It is better when using new oxide for the first time to mix a little old with it, to reduce the percentage of moisture.
A little old oxide mixed with new assists its action at first, as will also the presence of a slight quantity of ammonia in the gas.
One equivalent of hydrated peroxide combines with about three equivalents of H2S.
36 parts of hydrated peroxide of iron will combine with 17 parts of H2S.
Room must be allowed for expansion of material upwards when revivified in situ.
Oxide should be laid in layers of from 12 to 18 inches thick.
Best method of using oxide is 2 layers of 18 inches thick.
(Hawkins.)
Oxide of iron is laid as thick as 2 feet 0 inches in some purifiers.
A thick layer of oxide, say 3 feet thick, will often have to be turned off, on account of back pressure, when only just put to work, but, as a rule, with thick layers of oxide no great increase of pressure need be feared if there be good scrubbing and washing beforehand.
Oxide usually laid about 10 inches to 12 inches thick on the grids.
Oxide should be laid about 10 inches thick to revivify.
Gas should not be allowed to enter a purifier much above the temperature of the oxide therein.
The avoidance by every possible means of high temperatures in the purifiers, or during the revivification, of the spent material is advis- able. (M. Godinet.)
Gas purified by oxide of iron is said to have a yellow tinge, while that purified by lime is whiter, the colour of the former being duo probably to the presence of C03.
Reaction in Oxide Purifiers,
Fe00,H00 + 3 H0S = Fe0S, + 4 H.,0 ; or Fe2"03H;o + 3 H;S = 2 Fe'S + S + 4 HaO,
OXIDE PURIFICATION. 269
Action of air when revivifying upon Fe2S3 + 4 HaO. 2 Fe2S3 + 3 00 = 2 Fc2 03 + 3 S8. 12 Fe S +9 02~= 6 Fe2 03 + 6 S2.
Oxide (bog ore) should remove 1st time 16 per cent., 2nd 6 per cent., 3rd 5 per cent, sulphur. Another authority gives —
Reaction of Oxide of Iron.
Fe203H20 + 3 H2S = Fe2S3 + 4 H20.
When revivifying —
Fe2S3 + 30 + H20 = Fe203H20 + 3 S.
Also hydrated oxide of iron removes H0S as per equation : —
Fe2033 H20 + 3H0S = 2FeS + 6 H"00 + S, and is revivified in the air as follows :— 2~ FeS + 3 H2O + 20=30 + Fe202H20 + 2 S.
H2S unites with the iron and forms sulphide of iron, the H, com- bining with 0 in the oxide forming water. After use in purifier the oxide is in the form of sulphide of iron, the iron absorbs 0 and leaves the sulphur in a free state.
It is not advisable to use oxide containing more than 55 per cent, to 60 per cent, free sulphur, as its utility is impaired, but when revivified in situ it can be made to take up 75 per cent.
When S in oxide equals 55 per cent. -the oxide is useless for purification. (Richards.)
Oxide can be used until it has taken up 60 per cent, by weight of sulphur, but has no action upon CO2.
New oxide, when revivifying, combines very rapidly with the 0 in the air, causing rapid evolution of heat.
Value of spent oxide should be sufficient to purchase all purifying material necessary for purification of gas from H2S.
It has been found that by treating spent oxide with caustic, lime, and soda sulphate at a certain temperature, an increased yield of sulphocyanatcs and ferrocyanides are obtained equal to about 40 per cent, above that obtainable by treatment with water.
Analysis of Spent Oxide. (J. Hepworth.)
Per Cent.
HnO 14-0
S" 60-0
Organic substances insoluble in alcohol . . .3-0 Organic substances soluble in alcohol consisting of calcium ferrocyanide and sulphaequinde, ammonium cyanidequinde, sal-ammoniac hydrocarbon . . . 1-5
Clay and sand 8*0
Calcium carbonate, ferric oxide, &c. . . . . 13'5
lotTo
About one-half the total sulphur present in coal passes forward to the purifiers.
The quantity of H2S requiring to be removed by the purifier may range from 200 to 2,000 grains per 100 cubic feet
270 GAS ENGINEER'S POCKET-BOOK.
Order of Value for Purifying Coal Gas of the Principal Limestones of this Country. (Hughes.)
1. The white chalk limestone of Merstham, Dorking, Charlton, Erith, and other parts of the chalk range surrounding the metropolis.
2. The grey chalk limestone, from the lower beds of chalk.
3. The blue beds of the upper and middle Oolites.
4. The lower white and grey limestones of the Oolites.
5. The most calcareous and crystalline beds of the carboniferous or mountain limestone, colours grey and bluish.
f>. The magnesian limestone of Yorkshire and Derbyshire.
7. The white lias limestone.
8. The blue lias limestone.
9. The Silurian limestone of Wenlock, Dudley, &c., and the coraline limestones of Plymouth and the neighbourhood.
Theoretical value of chalk when made into lime is 100 Ibs. chalk equals 56 Ibs. CaO as per equation : —
CaC03=Co0 + CaO. 100 = 44 + 56
In practice 1 ton chalk makes on an average 1 yard lime ; (13,596 tons chalk made 13,300 yards lime). (Actual experiment, 17th May, 1893.)
Lime.
25 striked bushels or 100 pecks equals 1 hundred of lime. 46.656 cubic inches, 1 cubic yard, or 27 cubic feet containing 21 f bushels, equal 100 lime.
] bushel of quick lime weighs about 70 Ibs. ] cubic foot stone „ „ ,f 54 „ J cubic yard quick „ „ „ 1,460 „ 1 ton „ equals 32 bushels.
About 40 Ibs. of lime are required to purify a ton of coals in large works.
Lime used in large and medium sized works in purification with oxide or other supplemental method ranges from 3-3 to 5*5 cubic yards per million cubic feet of gas.
By the rotation method of purifying, 1 yard unslaked lime is required per 35 tons of coal used.
165 Ibs. Irish unslaked lime will clean about 35,000 cubic feet of gas.
Quantity of lime required to extract C02, about 3*3 yards per million cubic feet.
Chalk lime is best for purification of gas from C02.
Lime often contains 5 to 20 per cent, of earthy matters which may cause it to become caked in the purifiers.
LIME PURIFICATION. 271
Lime ready for the purifiers generally contains 30 to 40 per cent, of water above that required for the making of hydrate of lime.
1 bushel quick lime increases to 2 J when slaked, and this should purify 10,000 cubic feet of gas. (Richards.)
Caustic lime when slaked about doubles in bulk as CaO + H2O equals CaH202.
28 parts of lime combine with 9 parts of water to form hydrate of lime or slaked lime.
28 parts of pure lime will combine with 22 parts of C02.
28 parts of pure lime will combine with 17 parts of H2S.
74 parts by weight of pure lime should combine with 44 parts of C02 or with 34 parts of H?S.
Sometimes when lime is used to remove C02, H2S and CS2 an oxide vessel is used last, to act as a catch purifier to take up any H0S that may be driven off from the sulphide vessel.
When lime only is used for purification the sulphur is wasted.
"Wet lime will purify double or treble the gas dry lime will.
(S. Anderson.)
Dry CO when present in a purifier containing dry hydrate of lime will not combine with it, but the addition of moisture causes the CaOH20 + C02 to become CaOC02 -f H20.
When water is added to lime calcic hydrate is formed as per equation : —
CaO -f- H20 = CaOH20.
Excessive water in the lime will cause the latter to cake and then impede the passage of the gas.
Lime usually laid about 4 inches thick on the grids.
1.650 Ibs. of lime will take up about 425 gallons of water when being mixed up for the purifier, or about 1 gallon of water to 4 Ibs. of lime.
Lime will cleanse about 35,000 cubic feet of gas per 165 Ibs.
Lime should be slaked two or three days prior to use in purifiers or it may cake ; slaking increases the bulk about 2£ times ; it should be ;is pasty as possible, and take the form of nodules about f inch to 1 inch in diameter. Dry lime is not so porous or so efficacious as a purifying material.
Mr. F. Egiier (U.S.A.) proposes to prepare lime for purifying as follows : — a thin layer, 4 or 5 inches deep, of unslaked lime should be laid out, and nearly the whole quantity of water poured over the lime. As the lime slakes it is turned over with long pronged rakes, then one-tenth of its bulk of screened coke breeze added and thoroughly mixed and moistened until a handful will stick together when tightly squeezed
Removal of Carbonic Acid.
Here lime purification should be adopted ; the material to be hot and divided in several layers. No special system of revivification need be followed.
' Pressure thrown by a lime purifier with sieves covered with from 12 to 15 inches of lime should never exceed 1 inch during its working.
2 1 '2 GAS ENGINEERS POCKET-BOOK.
Pressure thrown by 8 layers of lime 10 inches thick has been as low as lj inch for a considerable period.
Lime is usually placed in layers of 4 to 6 inches thick. Approximate action of lime on H2S in purification is expressed probably by the following equation : —
CaOH20 + H2S = CaS + 2 H20
Lime meeting C02 in gas without H2S forms calcium carbonate CaO + C02 = CaC08
Lime first attacks both the C02 and H2S, forming carbonate and sulphide of calcium, but later the C02, having a greater affinity for the lime, drives off the H2S and forms carbonate of calcium only.
When gas containing C02 and H2S meets lime : —
CaH20 + 2 H2S = CaS, H3S + 2 H20 \
" or CaH202 + H2S = CaS + 2 H20 \ formed simultaneously,
and CaO + C03 = CaC03
afterwards the CaS + C02 + H20 = CaC03 + H2S
the H2S being driven forward owing to the greater affinity of the C02 decomposing the CaS ; but if air is admitted a certain portion of the H2S is converted into free sulphur and it cannot then be sent forward.
About 70 Ibs quicklime is required per ton of coal in small works. „ 130 „ „ „ „ „ ., cannel.
1 bushel quicklime weighs about 70 Ibs. = 1*3 cubic feet. 1 cubic foot chalk lime ,, „ 45 ., = 0'771 bushels. 1 cubic yard „ „ „ 1,460 „ = 20.9 „
1 toil „ measures „ 32 bushels.
Lime ready slaked for the purifiers should weigh about 90 Ibs. per bushel.
Mr. Forstall has suggested passing the slaked lime through sieve with 1 inch square mesh set at an angle of 70° with the floor, and the lime should not be wet enough to cling to the sieve.
If lime be allowed to become too dry and powdery C02 will speedily slip, and if too wet the result is not satisfactory ; both extremes should be avoided. If cold gas be introduced into a hot material the latter is rendered powdery, and if hot gas is introduced into a cold material it is made too wet,
Removal of the Sulphur Compounds.
The cost of removing the sulphur compounds may be taken as ovei Id. per thousand cubic feet.
Where oxide of iron is used there should be a large purifying surface and prolonged contact with the purifying material, which should be in one or several layers according to the use or non-use of
SULPHUR COMPOUNDS. 273
inert materials. Where revivification is effected in. the open air, the material should be heaped up on its removal from the purifiers, and, as soon as it becomes heated, spread in layers from 8 to 12 inches thick. Where continuous revivification is employed the volume of air or oxygen should be injected without interruption and in exact proportion to the make of gas, the material to be kept warm and moist. In the case of purification by lime the material should be divided into several layers and used cold if it is desired to retain more of the sulphide of carbon, otherwise hot. Oxygen should be employed for revivification.
Quantity of Sulphur Compounds from Same Coal.
Yield of Gas Sulphur per 100 Cubic Feet
per Ton. other than H^S.
grains. 6,893 . *; . . . . 13'9
8,370 ...... 19-1
9,431 ...... 2(>-7
10,772 ...... 3(5-9
11,620 ...... 44-1
If C03 be allowed to pass into a sulphided lime purifier it will liberate some of the HaS and CS3 already taken up and form car- bonate of calcium in its place.
If H3S be allowed to pass into a properly sulphided lime purifier it changes the monosulphide to a polysulphide, which has no effect upon the CSa.
Of the 45 grains S. other than H2S in coal gas per 100 cubic feet, the CO3 purifiers remove 10 grains, the sulphided purifiers remove 25 grains.
Carbon bisulphide (CS2) is usually removed by a lime purifier, through which a quantity of gas free from C02 but containing H3S has been passed, the H2S combining with the lime to form sulphide of lime, which latter will remove practically all the CS2.
The removal of the sulphur compounds is not rendered more certain by the admission of 1 to 2 per cent, of air at Nos. 3 or 4 purifiers at Rotherhithe. (A. F. Browne.)
Probable action in sulphided lime purifiers.
CaS + CSa=CaCS8 or,
CaSH30 + CSa = CaCS3+HaO
The calcium pentasulphide may also combine with the 0 admitted in the air thus : —
CaSB + 03=:CaS003 + S3
or with C0a thus :—
CaS5 + C0a + HaO = CaC03 + HaS
G.E.
274 GAS ENGINEER'S POCKET-BOOK.
Laming material consists of sulphate of iron, 250 kilogrammes ; slaked lime in powder, 1 hectolitres, inert material, 7 hectolitres.
The stability of the sulphide of lime, as measured bj the action upon it of C02, depends largely upon the temperature at which the sulphide is formed.
The energy of union as between calcium sulphide and CS2 is sharper and much more complete when the sulphide is prepared from hot lime, and is maintained at about the temperature of 75° F. Sulphide so made and used is said to have 30 per cent, greater efficiency ; and by chilling the vessel the efficiency can be reduced to nil.
A very small quantity of CO., passing into a sulphide vessel materially decreases the efficiency."
Weldon mud is a bye product from the manufacture of bleaching powder with lime and air, and consists principally of hydrated oxides of manganese Qln03 and MnO) and of calcium.
Weldon mud will absorb about four to live times the HaS that oxide of iron will, forming sulphide of manganese and water.
Weldon mud equals about 52 per cent, water and 26 per cent, manganese dioxide, and should remove 2S'l per cent. 8 first time, 16*7 per cent, second time, 5'S per cent, third time.
About 1 per cent, of air is considered best with Weldon mud when it is used for the first removal of H2S.
About 10 to 15 grains H2S per 100 cubic feet is contained in the gas when it reaches the check purifiers, where lime or Weldon mud is found more active for such small quantities than oxide of iron. Weldon mud with about J per cent, of air has continued active in this position for two to three years, and is said to represent a labour saving as against lime of 1 to 16 ; the pressure thrown decreases with time, whereas with lime and oxide it increases.
Comparative quantity of oxide shifted at Bcckton per 100,000,000 cubic feet gas made, 503 cubic yards as against 50 cubic yards of Weldon mud ; this refers to the material used in the primary elimination of H2S.
In the all lime purifying method about 1 j per cent, air is about the best quantity.
The use of air greatly mitigates the bad smells given off by oxide when it is first removed from the purifiers, and doubles the length of time the purifiers will last without recharging.
Air used with lime purifiers will cause the sulphur taken up by the lime to be converted into free sulphur to the extent of 10 per cent., instead of being driven off by the C02.
The use of air (1J per cent.) in purification enables the oxide to absorb some 25 per cent, sulphur before it need be removed for complete revivification.
Purifiers by the air process have been filled with oxide, and not again discharged until the material contains nearly 60 per cent, of sulphur.
More than 3 per cent, air not only reduces the illuminating power, but is inclined to cake the oxide and to raise the temperature of the material.
The admission of air or oxygen to the purifiers effects an oxidation
REVIVIFICATION IN SITU. 275
of the sulphur compounds of the lime, and sulphur is deposited as such in the foul lime. (Butterrield.)
Air may be used in a sulphide vessel to reconvert a polysulphide into a monosulphide, or to render a box sulphided at a low tempera- ture active.
Steam, when used to inject air into purifiers, has been found to prevent the caking of the oxide; it has been suggested to introduce it at the inlet to first purifier so as to raise the temperature to 100°.
Revivification by steam jet in situ may set fire to the grids.
Mr. Carpenter admits 1 per cent, air into the third or fourth purifier and thus obtains the desired effect on the ones required for the removal of the sulphur compounds.
When air is used (2 per cent.) to aid purification in oxide vessels the use of ammonium hydrate (ammoniacal liquor 4° Twaddel) sprinkled on the oxide before use is found to increase the life of the charge from 80 to 100 per cent. (R. G. Shadbolt.)
Two and a half per cent, air used in purification lowered 17*3 candle gas to 13'45 candles.
Three per cent, air used in purification lowered 17*3 candle gas to 13-04: candles.
Five per cent, air used in purification lowered 17 '3 candle gas to 10'59 candles.
Seventeen and a half per cent, air used in purification lowered 17'3 candle gas to 1*0 candle.
An arrangement for pumping into the gas at the inlet of the puri- fiers 3 per cent, air carburetted with tar of specific gravity 1-190, kept at a temperature of 170° by a steam coil, was patented by Mr. Hawkins, to remove the loss of illuminating power occasioned by the use of such a large quantity of air. The specific gravity of the tar after leaving the carburettor was 1'21S. The only objection appeared to be the possibility of a deposit of napthalene in the mains during severe winter weather. The illuminating power appears to have been maintained throughout the district.
The quantity of air necessary, according to theory, for continuous revivification of oxide is 2£ per cent, air for 1 per cent. H2S. A slight margin in excess is, however, necessary in practice for safety.
It is said that the higher temperature in a purifier, due to the increased chemical activity of the purifying material when air is used, prevents the deposition of some of the valuable hydrocarbons, which in the ordinary way would be condensed ; the napthalene on the under side of a purifier cover in winter clearly showing that such a deposition will take place.
Advantages claimed for the use of 0 with oxide of iron purifi- cation are — Almost complete revivification of oxide in situ ; increased illuminating power ; greatly augmented percentage of sulphur in spent oxide, and consequent higher market value ; the purification more efficiently conducted, with half the purifying space and two-thirds of the material ; a corresponding saving in capital and labour.
Lime can be wholly used in conjunction with oxygen for the puri- fication of gas. By the regulation of quantity of 0 to quantities
T 2
'21 6 GAS ENGINEER'S POCKET-BOOK.
of impurities sulphur compounds can be removed. Purifying space and plant now required for lime reduced by more than one-half, lime used by nearly one-half, and labour in proportion. Auxiliary oxide of iron purifiers are rendered unnecessary. Very considerable saving is caused by improvement in illuminating power. Sulphur deposited possibly recoverable. (W. A. Mel. Valon.)
With oxygen and lime only and average of 620 grains S per 100 cubic feet at inlet, 2 cubic yards lime per million cubic feet kept sulphur compounds down to an average of 0 to 8 grains per 100 cubic feet, and the illuminating power maintained at 16'5 candles. (W. A. Mel. Valon.)
Proportion of Oxygen Required for Purification.
O'l per cent., by volume of oxygen for every 100 grains, H2S per 100 cubic feet removes all the H2S and C02, and reduces the sulphur compound to 7 or 8 grains per 100 cubic feet of puritied gas.
One foot pure 0 is sufficient to remove 1,000 grains H2S in the crude gas ; or '1 per cent, by volume of 0 per 100 grains Hn$ per 100 cubic feet.
One half the volume of HaS in the gas is required of oxygen to revivify the oxide in situ.
No increase in heat is found in the oxide when using 0.
When oxygen is used with lime purifiers the H2S first taken up by the lime is not expelled again by the C02, but the S is thrown down in the form of grains of pure sulphur, leaving the lime as active for the C0a as if no sulphur had been retained.
To Prepare Oxygen.
When air is compressed over water, the components of the atmos- phere are taken up in direct ratio of the pressures employed. On releasing the pressure, there is proportionally more oxygen in the evolved gases ; by repeating the process eight times 97'3 per cent, oxygen can be obtained.
Composition after Successive Pressures. N. 79 6G-67 52-5 37'5 25-0 15'0 9-0 5-0 2'7 O. 21 33-33 47-5 62'5 75'0 85'0 91'0 95-0 97'3
For a material to revivify in situ it must have a strong affinity for 0, so as to combine with it energetically as it passes through the gas.
Cyanogen.
It would appear from the reactions expressing these changes that the cyanogen exists in coal gas exclusively in the forms of cyanide and sulphocyanide of ammonium.
Ferrocyanide of iron is formed if cyanogen and ammonia in only small traces are allowed to get to the oxide purifiers ; this reduces the activity of the oxide for the removal of H2S.
A large portion of the cyanogen combines with the iron in the purifiers to form a ferrocyanide or Prussian blue, but the quantity is reduced if first passed through lime.
CYANOGEN.
277
Average per cent, of sulphocyanic acid, ammonia, and potassium ferrocyanide obtained from 12 German gasworks —
HCNS = 2-62, NH3=l-87,
-f 3aq = 5-1.
Ib. Prussian
One ton of coal by the Glaus ammonia process yields blue and If Ibs. copper sulphocyanide.
Leybold found cyanogen equal to about 4 Ibs. of ferrocyanide in 10,000 cubic feet of gas, of which nearly 95 per cent, remained in the scrubbed gas. When lime is used for purifying the gas, the cyanogen is lost ; and if iron be used the cyanogen is converted largely into sulphocyanide in which form it is not so readily available. But when the gas after it leaves the scrubber is brought into intimate contact with precipitated oxide of iron, suspended in an alkaline solution, as recommended by Knublauch, the cyanogen is easily obtained as ferrocyanide, almost free from sulphocyanide.
Removal of the Cyanogen Compounds.
To ensure material rich in Prussian blue keep the stuff very moist at a low temperature, have a large purifying surface and long con- tact. When revivifying in the open air spread the material in very thin layers kept quite moist ; but if in situ inject cold air saturated with moisture at great speed. In the case of continuous revivifica- tion the opposite process must be adopted, owing to the presence of less sulphide of iron in the purifiers.
Oil gas tar will remain on the sides of purifier covers, also petroleum oil.
Composition of Purified Illuminating Gas.
|
COMMON GAS. |
|||
|
Authority. |
Permanent Gases. H, CO, He, &c. |
Illuminating Compounds or Light Bearers. |
Impurities, H2S, C02, NH3J &c. |
|
Bunsen Letheby (12 candle gas) Odling ;> •" • ., . . . n * ' • |
87-12 93-00 90-42 93-92 89-83 90-03 96-01 |
6-ofi 3-80 3-05 3-56 3-07 3-63 3-53 |
6-42 3.20 0-53 2-53 6-50 0-40 0-46 |
|
CANNEL GAS. |
|||
|
Letheby (22 candle gas) Odling .... Two analyses of water \ gas as sold in New York ) |
84-05 88-00 / 78-90 \S1-16 |
13-00 10-81 15-29 15-29 |
2-50 1-19 4-8 3-5 |
278
GAS ENGINEER'S POCKET-BOOK.
Composition of Purified Coal Gas. (Professor V. B. Lewes, 1890.)
|
H |
Per Cent. 47-<> |
|
Illuminants, ethylene series . . . 3-5 .. benzene ., . . . 0-9 » methane '.. . . 7-9 Methane . . . " . . . 33-3 " CO. . . . . fi-n |
|
|
C(X . |
O'O |
|
o 2. |
0'5 |
|
N |
o-o |
1 00-0
STORING GAS.
279
GASHOLDERS (CARE OF).
It takes a considerable time for the diffusion of gases of different densities even when of great difference of density, when in conditions usual in gasholders.
Diffusion of Gases,
The velocity of diffusion of different gases is inversely propor- tional to the square roots of their densities.
|
Density. Air=l |
l ^/Density. |
Velocity of diffusion. Air = 1 |
|
|
Hydrogen . Nitrogen. . . . Oxygen Carbon dioxide . . |
0-0<592(> 0-97130 1-10560 1-52900 |
3-7790 1-0150 0-9510 0-8087 |
3-830 1-014 0-949 0-812 |
(Graham.)
Gases of different specific gravity will mix in time, but, owing to the temperature of either the incoming gas or the heat of that in the holder, the mixing may take a considerable time, the warmer gas keeping to the top of the holder. From the heat of the sun, the crown of a gasholder becomes so hot that it cannot be touched with the hand, being at least from 113° to 122° F. (W. Ley bold.)
The contact of ordinary coal gas with water is found to cause a rapid diminution in illuminating power. (Irwin.)
Carburetted water gas stored in a holder for 17 days, lost 1£ candles in value at Blackburn.
Napthalene in gas holder inlet pipes is usually found to commence at and continue below the level of the surrounding water.
Do not lower a telescopic holder in a gale so as to leave the upper lift only exposed. As the centre of gravity is very near the crown, it is the more easily overturned, while, if the second lift is out of the water its weight brings the centre of gravity considerably lower.
Frost has been known to cause the sides of brick tanks to bulge inwards and prevent the holder moving up and down.
Painting Notes.
Gasholders should be first made clean by scrubbing and brushing with wire brushes, any bubbles of the old paint being scraped off with an old file sharpened at the edge.
Before painting a holder well scrape tbe old paint and remove old blisters and scales which might cause a lodgment of water and consequent oxidation of the plates.
GAS ENGINEERS POCKET-BOOK.
With paint, too much oxide is not good for the oil which is then oxidized tco quickly and rendered natureless, so that the paint eventually powders off. (Wood.)
A Coating for Gasholders.— Mix and raise to boiling point, 1 gallon of tar and £ Ib. asphalte, then add 1 pint coal naptha and £ Ib. tallow. Use warm.
The outer surface of gasholders may be covered with paint, or tar mixed with tallow, and it has been proposed to do this in the spring and also autumn each year.
Oil gas tar is an excellent paint for gasholders.
Tar for painting should only be raised sufficiently high in tempera- ture to drive off all the water, should be fluid when cold, too thick for use, and can be thinned with turpentine, 1 turps, to 4 tar ; 1 gallon will cover 64 square yards of metallic surface.
Red lead sets harder and sooner than white lead.
Contents of crown, to find : Square the radius of the holder, multiply this square by 3 ; to the product add the square of the rise and multiply by -5236.
In filling the holder with gas it is best to use a high-class coal, and so compensate for the air in crown, as it is difficult to expel the latter.
DISTRIBUTING GAS. 281
DISTRIBUTION.
Mains. Services. Meters.
Quantity of gas, in cubic feet, discharged per hour by any main can be found as follows : —
X=133"VM
Where—
?i = pressure of gas in inches of water. d = diameter of pipes in inches. S = specific gravity of gas (air = 1) L = length of pipe in yards.
(Dr. Pole.) Another rule is —
x= 1,000
(Molesworth's Pocket Book.) And another is —
X = 1,000 ^I-E
(Spon's Pocket Book.) The first is the most correct.
Plow of Air in Pipes. (Hawksley.) Velocity in feet per second =
396 /head in inches of water x diameter of pipe in feet
length of pipe in feet
Head in inches of water = lcngth of pipe in feet x velocity 156,800 diameter of pipe in feet
Contents of pipe = square of diameter x '7854 x length ; contents in cubic feet x 6-26 = gallons.
Weight of cast iron pipe = K (D2 — rZ2). K = (for cast iron) 2-5.
Flange equals, say. 1 foot of pipe in weight.
In a 24-inch pipe delivering 240.000 cubic feet per hour into one 18-inch pipe and two 14-inch pipes at a distance of about 2,000 yards
the pressure was reduced from — to —
282
GAS ENGINEERS POCKET-BOOK.
250
Capacity of pipes. 500 750 1000
1250
16,000
14,000
13,000
1250
1500
DELIVERING POWER OF PIPES.
Capacity of pipes.
283
9" 9"
niaAed
I
,/ 1
- 4"
250 500 750 looo 1250 1500 1750 length in yards,
284
GAS ENGINEER'S POCKET-BOOK.
250 500 750
Capacity of pipes. 1000 1250 1500
175°
IOOO I2£O
Length in yards,
1750
LEAD REQUIRED FOR JOINTING.
285
Relative Carrying Capacity of Gas Pipes. (Compiled from Tables by Norwalk Iron Co.. U.S.A.)
Inches.
24 = I'OO . 12 = 0-17
10 = 0-10 . 8 = 0-06
7 = 0-04 .
6 == 0-03
5 = 0-0189 41 = 0-0141 .
4 = 0-0102 31 = 0-0069 .
3 = 0-0045 2.i = 0-002835
2 = 0-001485
11 = 0-000810 IA = 0-000450
1 = 0-000225
Comparative Areas.
. 1-00
. . 0-25
. 0-175
, . 0-111
. 0-085
. . 0-0625
. 0-0434
. . 0-0351
. 0-0278
, . 0-0212
. 0-0156
. . 0-0108
. 0-0069
. . 0-0039
. 0-00272
. 0-00173
Weight and Depth of Lead in Pounds for Ordinary Lead Joints.
|
Diameter of Pipe. |
Weight of Lead. |
Depth of Lead. |
Diameter of Pipe. |
Weight of Lead. |
Depth of Lead. |
|
Inches. |
Lbs. |
Inches. |
Inches. |
Lbs. |
Inches. |
|
2 |
If |
H |
12 |
18J |
2| |
|
3 |
2f |
1| |
13 |
21 |
2| |
|
4 |
4 |
if |
14 |
23 2 |
|
|
5 |
5j |
11 |
15 |
26 |
2| |
|
6 |
7 |
2 |
16 |
28.1 |
2i |
|
7 |
8| |
2 |
17 |
31 |
2| |
|
8 |
2J |
18 |
32£ |
2| |
|
|
9 |
12^ |
2& |
19 |
34 |
2| |
|
10 |
14j |
2? |
20 |
35J |
|
|
11 |
16* |
Sji |
24 |
48 |
38 |
For pipes up to 8 inches in diameter the lead is taken at f inch thick, and for pipes from 9 inches diameter upwards the lead is taken it £ inch thick.
286
GAS ENGINEER'S POCKET-BOOK.
60-
A SO Ibs. each.
Weight 1 20 /6s. each.
Hrrar
I*
4: 5
s'o
|
* |
* |
J '!* |
u «n |
r |
|
5S;< »V«/>/r/-2?0.0.«ac*. __Js5SB^ |
|
|
[ "M |
•4 7 i » |
|
^*»^ |
6" ^
|
[^ IVe/y/)A 2f 2.0 oach. _j. |
l»SJ |
|
\ t! 1 j !T2 |
c |
|
*i>^ |
i1*
s'o-
8* s,; «
v, v.
s'o"
|
[ v v, i |
1 |
CD 5 |
|
^ \^ < 4-% |
.... A. |
|
|
.O.each. ^ |
•T,-.^ |
- . - - -y^ |
|
*eo »> oj* |
t^> |
& '? |
|
I |
| « |
|
|
X |
^ad |
L-.-*. |
|
< Ai'J |
||||
|
* |
Weight ^O.O.each |
|||
|
c |
1 < |
> 1 ( '? '^ ^ |
* i |
i? |
10'
12" «-
14" '*
24"
DIMENSIONS OF PIPES.
5'0" Weight 4? 2.0 each.
- - 12 0
Wtiyhl-892.ll.each.
WeighH090.il each.
Weight- 109 3.7.each
Weight 22? 3.0. each.
12' 0"
287
VR
* 4ft
I 'if t
288
GAS ENGINEER'S POCKET-BOOK.
Mains.
48-inch Socket joint requires 90 Ibs. lead and 8 yards yarn.
|
48 , |
Flange |
|
|
36 . |
Socket |
|
|
36 , |
Flange |
|
|
30 , |
Socket |
|
|
30 , |
Flange |
|
|
24 , |
Socket |
|
|
24 |
Flange |
|
|
18 |
Socket |
|
|
12 |
||
|
11 |
||
|
10 |
||
|
9 |
. |
|
|
8 |
', |
|
|
7 |
||
|
6 |
||
|
5 |
||
|
4 |
u |
|
|
3 |
144 72 108 (50 90 48 72 32 18-2 14-9 11-5 10-4 8-2 7-7 6-5 5 4 2-6
Flange joints made with wrought-iron ring ^-inch thick placed between flanges and bolted up, afterwards run with lead and set up.
Yarn weighs 1 qr. 23£ Ibs. per 250 yards equals 1 coil.
All mains above 6 inches diameter should be cast vertical so that a few inches at the end may be cut off and any porous part removed.
Cast iron gas pipes should be tested by at least a head of 200 feet of water, or about 90 Ibs. to the square inch.
Cast iron pipes should be of close grain and equal thickness throughout. This can be found by rolling them on two rails or metal edges and noting if there be a heavy side by the pipes always rolling to one position, and they should emit a bell-like sound when tapped with a hammer.
They should be tested to from 90 to 130 Ibs. per square inch, and tapped while under pressure ; if water is seen oozing from cracks or flaws the pipes should be rejected.
PIPE JOINTS.
289
Dimensions of Cast Iron Pipe Flanges to bear 75 Ibs, Pressure. (Briggs.)
|
-53 • |
8 • |
a> |
o . |
03 <D~j |
CO a |
eg |
Ǥ5g |
§5« . |
o |
;_ . |
|
Jf! |
1! |
C 0 |
f J |
||| |
III |
II |
l|| |
||l |
Ss c o |
!« |
|
MQO |
a* |
£° |
d |
il'ss |
H o^ |
5§ |
°5-3 |
5 o^ |
jlm |
So |
|
3 |
•328 |
•40 |
1-25 |
•50 |
•56 |
•55 |
ft |
5| |
4 |
i |
|
3'. |
•341 |
•42 |
1-28 |
•51 |
•57 |
•61 |
7| |
^U) |
4 |
|
|
4 |
•354 |
.43 |
1-30 |
•53 |
•59 |
•61 |
8 |
6-7- |
5 |
Jl^ |
|
5 |
•380 |
•46 |
1-35 |
•56 |
•63 |
•61 |
9 |
71 |
6 |
^ |
|
6 |
•406 |
•49 |
1-40 |
•60 |
•67 |
•68 |
10* |
gii |
6 |
I |
|
8 |
•458 |
•55 |
1-50 |
•66 |
•74 |
•68 |
12* |
10^ |
8 |
|
|
10 |
•510 |
•61 |
1-60 |
•73 |
•81 |
•81 |
15 |
13— |
10 |
i |
|
12 |
•563 |
•67 |
1-70 |
•80 |
•89 |
•93 |
17| |
15,9_ |
10 |
i |
|
16 |
•667 |
•79 |
1-90 |
•93 |
1-01 |
•93 |
22 |
i4 |
14 |
! |
Dimensions of Socket Joints. (Unwin.)
Where ^ = thickness of pipe and d = diameter of pipe. tl = l'07t + i
f2 = 0-025rf + i to 0-025^ + 0-6 f3 = 0-045^ + 0-8 .9 =0'01rf + -25 to 0-Olrf + -375 &x = 0-075(7 + 2i
3 and 54 = 0'
2| to
Thickness of Pipes for 90 Ibs. Pressure per Square Inch up to 20 Inches Diameter, and up to 75 Ibs. Pressure per Square Inch up to 60 Inches Diameter.
|
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
|
|
Diameter of |
||||||||||||
|
Pipe . |
4 |
8 |
12 |
16 |
20 |
24 |
30 |
36 |
42 |
48 |
54 |
60 |
|
Thickness . . |
I |
& |
i |
£ |
1 |
3 |
g |
t |
§ |
1 |
y |
1 |
O.K.
290
GAS ENGINEER'S POCKET-BOOK.
Dimensions of Turned and Bored Pipes in Inches.
|
Dia- meter |
Thick- |
Depth Ot* |
Thick- ness |
Thick- ness |
Dia- meter |
Thick- |
Depth |
Thick- ness |
Thick- ness |
|
of Pipe. |
ness. |
Socket. |
of Rim. |
of Socket. |
of Pipe. |
ness. |
of Socket. |
of Rim. |
of Socket. |
|
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
Ins. |
|
2 |
155 |
3 |
1 |
\ |
11 |
9_ |
4i |
1*8 |
$ |
|
3 |
I |
3| |
1 |
I |
12 |
A |
4i |
iy |
i |
|
4 |
& |
4 |
H |
a |
18 |
§1 |
4i |
ii |
15 10 |
|
5 |
JL 10 |
4 |
if |
S |
14 |
19 |
H |
il |
8 |
|
6 |
4 |
H |
I |
15 |
1 |
5 |
2 |
i |
|
|
7 |
1 |
4* |
4 |
i |
16 |
i |
6 |
2 |
i |
|
8 |
i |
4i |
it |
H |
17 |
i |
6i |
2i |
4 |
|
9 |
i |
4i |
r |
18 |
y |
61 |
2* |
5 |
|
|
10 |
i |
*i |
if |
i |
20 |
ti |
H |
?J |
8 |
THICKNESS or RIM
yfofrTmcKNEss or SOCKET
Weight of Socket of Cast Iron Pipes.
3
4
0 7 8 9 10
11
|
= 6-64 „ |
15 |
|
= 11*2 „ |
18 |
|
= 14-45 ;, |
20 |
|
= 21-0 „ |
21 |
|
= 24-8 „ |
24 |
|
= 33-0 „ |
30 |
|
= 37-36 „ |
36 |
|
= 41-7 .. |
42 |
|
= 52-36 ;; |
48 |
|
= 57-27 „ |
12 inches diameter = 90-54 Ibs.
= 112-36 „
= 147-64 „
= 179-0 „
= 188-0 „
., = 250-0 „
= 346-0 „
= 480-0 „
= 589-0 „ = 707-0
Weight of socket equals '9 foot of pipe.
Weight of socket turned and bored and thickened spigot equal to ri feet of pipe. Weight of flange equals 1 foot of pipe.
Depth of Socket. Jointing Space. 2 inches and 3 inches diameter 3 inches f inch
9 " t0 20 " *. " f "
? " » ZU 5? !• *2 J> 2 5J
21 » » 30 „ ., 5 „ £ „
Above „ „ „ 6 A
LAYING MAINS. 291
To Test Mains in District.
The portion of main to be tested must be isolated by bagging or water-logging, and a pressure put upon it by a motive power meter or small holder. The quantity of gas or air required to keep up the initial pressure equals the loss through leakage.
Coating for Pipes.
A composition of Burgundy pitch, oil, resin, and gas tar is made up in a bath, into which the pipes are lowered, where they remain until they attain the heat of this composition, which is about 142° F. They are then taken out and placed in such a position as to allow all unnecessary matter to run off.
To find the force tending to dive off a bend on a line of pipes sub- jected to internal pressure. The resultant force in the straight pipe on either side of the bend being equal to the area, A, of the pipe, X the intensity,^, of the pressure, and acting axially. The resultant of these
Q
two forces is A x p X 2 sin. _. where 6 is the angle subtended by the
bend.
Pipes up to 9 inches diameter should never have less than 1 foot 9 inches of ground above them ; above this size the depth should be increased at least G inches.
Pipes laid in clinkers and ashes will, after a time, part with a con- siderable portion of their iron, leaving a substance which can be easily scraped with a penknife. Clay, however, forms a most excel- lent'soil for pipe laying. It has been noticed that gas pipes are attacked at points where electricity leaves them when in proximity to electric tramways, and not where the current penetrates them.
Pipes with rough interior surface have been, known to reduce delivery of liquids 33 per cent, from that delivered when smooth. (Fitzgerald.)
Never drill a larger hole than | inch in a 2-inch main. Never drill a larger hole than 1 inch in a 3-inch main.
In small mains a 2-inch bend may be fixed to a reducing socket and a 1-inch service carried from that without materially reducing the quantity of gas which may be passed, and at the same time this method renders a small main less liable to leak.
Allow a fall of 3 inches per 100 yards in street mains ; or better, mains should have a fall of about 1 inch in 20 yards as a minimum.
Lay mains with a fall of not less than 1 to ^ inch to every 9 feet length.
Where pipes have to be carried across exposed positions, as when they are slung or fixed outside bridges, <fcc., they should be covered with felt or other non-conducting material.
Sleepers may be used with advantage under mains when laying in bad and soft ground.
The ground should be well, consolidated under mains to prevent subsequent uneven settlement,
U2
292
To find a leak try with a pricking bar near each socket, and to the full depth of the bottom of the main ; and if gas be present, even in a very small quantity, it will burn with a more or less blue light.
A broken pipe may be temporarily bandaged with stout calico well plastered with white and red lead, until a new pipe can be laid.
When lead pipes are used for services they must be supported their entire length, to prevent sagging and subsequent accumulation of water and stoppage of supply.
Service pipes may be made to last longer by receiving one or two coats of good oxide paint or hot tar.
It is better to use soap and water (soft soap is best) than to employ a light to try if a joint in a main be tight or no.
Millboard joints should be well soaked in \vater and painted both sides with red and white lead.
Gas valves should stand 5 Ibs. pressure on side opposite springs.
One or more trunk mains should always come from the works and terminate at central points, whence the distributing pipes may start.
A piece of tallow in the " gate " of the joint when running with lead prevents blowing even if the yarn or pipe be wet.
If too much lead is left on the outside of a joint the caulking up may split the socket.
The yarn should not occupy more than half the depth of the socket when driven hard in with the tool.
Ordinary putty may be used instead of lead for temporary joints after the yarn is well rammed in.
It is the return currents of electricity which are responsible for the electrolytic action ; and it seems to have the same effect on galvanised, tar coated, or so-called "rustless" pipes.
Cement for the Repair of Leaks in Gas and Other Pipes.
To 5 parts of Paris white add 5 parts of yellow ochre, 10 parts of litharge, 5 parts of red lead, and 4 parts of black oxide of manganese. The constituents should be well mixed and a small quantity of asbestos arid boiled oil added. The cement hardens in from two to five hours after application to the leaks, and exposes no fresh holes on drying. As the use of the cement does not involve the removal of the *pipes it is especially adapted for the repair of those which are difficult to get at.
In South Boston, U.S.A., all mains are laid with cement joints, made by using two hard-twisted rolls of lath-yarn, and a mixture of 2 parts of common cement, one part Portland cement, and one part sand.
Turned and bored pipes are cheaper to lay, but do not allow of any settlement, and consequently break easier than the open lead joint.
RACK AND PINION GAS VALVES.
293
<MC^<N<N<N<N<MC<ICO
HN-iN ______ . rH Cd C .
<M(M<MC<I<MC<I<M<MC<1CO
| .3 H
"cu +3 o
-If) -IN -ID -IN
NWNcqcNNNeftfioafc^io
-IN -IN HN
rHi-HrHrHr-(i-Hr-((NC<IS^C<)«<lC<lCCCC«C^tl»C
il
S -lNH« -iM -lN-iN -IN -IN -IN
,a«o oo 0*0 N •* »a *» ce o e* ca «* «o o» O »-( eo to «o d> «o co
O rHi-HrHrHi-HrHrHIMfMlMiMlMlMCCJCeCICCCffO^O
(M <N <M (M (M C<>
CO 00 CO
co co •* o
294
GAS ENGINEERS POCKET-BOOK.
ize alv
r-IC$^«Ot-© <M 0* <N <N (tt CO
H» HN Ml* -4N •«!«->!» u:«r«;M
f-t^o>oW'<*b- cs -H
<MCC
> wloe H» wloc -CIM Hoe H-» wH1 Hi"
wloeUce «!« Mice HM Hce soht «!•* -!•*
rsssss-s-ssssss-ssa §s s%
O CO <M!N
oHM nWH-*HMWl<* HMHtnlooHM HM
<M N W CO «
HACK AND PINION GAS VALVES.
295
296
GAS ENGINEER'S POCKET-BOOK.
Service Pipes. If the distance from the main does not exceed 30 yards —
1 to 10 lights require f inch wrought iron tube. 11 „ 30 „ „ 1 ,, ,, „ .,
31 „ 60 „ „ 1^ ;, „ „ „
61 120 li
Allowing for partial closing of the pipes through corrosion ; i inch and smaller wrought iron tube should not be used.
Lead, copper, -compo. and brass tubes are measured by outside diameter ; iron pipes are measured by internal diameter.
Cast iron pipes should be laid with a fall of J inch per pipe for outdoor mains, with ground well packed under joints before filling in, and not less than 21 inches from surface of ground.
Service Pipes. (Shaw.)
|
Greatest Number of |
||
|
Internal Diameter |
Burners allowed, |
|
|
of Pipe. |
at 5 Cubic Feet |
|
|
per Hour. |
||
|
Inches. |
||
|
1 i* |
10 25 45 |
1 Length of pipe, say, not ( more than 100 feet. |
|
l\ |
70 100 |
/ Length of pipe, say, not I more than 200 feet. |
|
2 |
185 |
Services should be connected to gas mains by bend and hole in top of main.
Half inch diameter services should only be used for public lamps.
All services in doubtful soil should be thoroughly protected.
Use hot pitch or a mixture of sand and tar in wooden troughs to prevent corrosion of service pipes.
WROUGHT-IRON TUBES. 297
Average Weight of Butt-welded Gas Tubes and Fittings.
|
Tubes (length = 14ft.) |
Fittings. |
|||||||
|
Bore. |
Weight per 100 Feet Run. |
Length re- quired to weigh 1 Ton. |
Weight of 10 Elbows. |
Weight of 10 Tees. |
Weight of 10 Crosses. |
|||
|
Inches. |
Lbs. |
Feet. |
Lbs. |
Ozs. |
Lbs. |
Ozs. |
Lbs. |
Ozs. |
|
i |
2fr3 |
8.502 |
1 |
1 |
1 |
0 |
1 |
8 |
|
40-5 |
5.532 |
1 |
7 |
1 |
8 |
1 |
14 |
|
|
I |
5 7 '5 |
3^892 |
1 |
13 |
2 |
4 |
2 |
3 |
|
82-9 |
2,700 |
2 |
15 |
3 |
0 |
3 |
4 |
|
|
a |
122-0 |
1,836 |
4 |
6 |
5 |
4 |
5 |
11 |
|
1 |
174-9 |
1,281 |
6 |
4 |
7 |
10 |
9 |
2 |
|
ij |
244-3 |
917 |
10 |
10 |
12 |
15 |
14 |
11 |
|
l| |
310-2 |
722 |
15 |
8 |
16 |
7 |
18 |
10 |
|
if |
359-5 |
623 |
15 |
12 |
20 |
0 |
21 |
4 |
|
2 |
421-0 |
532 |
22 |
6 |
27 |
0 |
31 |
4 |
|
2* |
515-0 |
435 |
30 |
2 |
32 |
8 |
41 |
4 |
|
a |
610-4 |
367 |
46 |
2 |
50 |
15 |
51 |
4 |
|
2| |
658-8 |
340 |
55 |
10 |
68 |
8 |
80 |
10 |
|
3 |
759-3 |
295 |
73 |
8 |
85 |
5 |
88 |
12 |
|
3^ |
878-4 |
255 |
101 |
0 |
121 |
0 |
129 |
0 |
|
4 |
1,032-3 |
217 |
126 |
0 |
144 |
0 |
158 |
0 |
Gas tubes are usually tested to 50 Ibs. per square inch, to 300 Ibs.j and steam tubes to 500 Ibs.
Water tubes
Weight of 1,000 Feet of Gas Tube, Ordinary Quality.
Cwts. Qrs. Lbs
|
i |
inch |
= |
2 |
2 |
0 |
H |
in |
ch = |
26 |
2 |
0 |
|
i |
;? |
=; |
3 |
2 |
18 |
if |
— |
35 |
0 |
0 |
|
|
i |
;j |
— |
5 |
1 |
18 |
2 |
i |
— |
40 |
0 |
4 |
|
£ |
55 |
= |
7 |
3 |
2 |
2i |
} |
— |
47 |
2 |
0 |
|
f |
;> |
= |
10 |
2 |
0 |
2i |
— |
59 |
2 |
16 |
|
|
i |
JJ |
== |
16 |
0 |
0 |
2| |
• — • |
74 |
3 |
26 |
|
|
H |
» |
= |
22 |
2 |
0 |
3 |
i |
= |
82 |
1 |
26 |
Table Showing Weight per Foot of Wrought Iron Tubing.
|
Internal Diameter. |
GAS. |
WATER. |
STEAM. |
|||
|
Weight per Foot. |
Weight per Foot. |
Weight per Foot. |
||||
|
Inches. |
Lbs. |
Ozs. |
Lbs. |
Ozs. |
Lbs. |
Ozs. |
|
£ |
0 |
l*i |
0 |
15 |
0 |
15J |
|
§ |
1 |
5£ |
1 |
7J |
1 |
8 |
|
1 |
1 |
15 |
2 |
2 |
3| |
|
|
II |
2 |
10 |
2 |
14 |
3 |
4 |
|
u |
3 |
2i |
3 |
9 |
4 |
0 |
|
2 |
4 |
H |
4 |
14 |
5 |
8 |
|
2^- |
o |
101 |
6 |
4 |
7 |
0 |
298
GAS ENGINEER'S POCKET-BOOK.
Whitworth Threads for Gas and Water Pipes.
|
Internal |
External |
Diameter |
No. of |
Internal |
External |
Diameter |
No. of |
|
Diametei |
Diameter |
at Bottom |
Threads |
Diameter |
Diameter |
at Bottom |
Threads |
|
of Pipe. |
of Pipe. |
Ot Thread. |
per Inch. |
of Pipe. |
of Pipe. |
of Thread. |
per Inch. |
|
Inches. |
Inches. |
Inches. |
Inches. |
Inches. |
Inches. |
||
|
i |
•3825 |
•3367 |
28 |
If |
2-245 |
2-1285 |
11 |
|
i |
•518 |
•4506 |
19 |
2 |
2-347 |
2-2305 |
11 |
|
1 |
•6563 |
•589 |
19 |
M ^ 8 |
2-467 |
2-351 |
11 |
|
i |
•8257 |
•7342 |
14 |
2* |
2-5875 |
2-471 |
11 |
|
1 |
•9022 |
•8107 |
14 |
2f |
2-794 |
2-678 |
11 |
|
I |
1-04] |
•9495 |
14 |
ft |
3-0013 |
2-882 |
11 |
|
1 |
1-189 |
1-0975 |
14 |
if |
3-124 |
3-009 |
11 |
|
1 |
1-309 |
1-1925 |
11 |
2* |
3-247 |
3-1305 |
11 |
|
1» |
1-492 |
1*3755 |
11 |
2f |
3-367 |
3-251 |
11 |
|
H |
1-65 |
1-5335 |
11 |
3 |
3-485 |
3-3685 |
11 |
|
if |
1-745 |
1-6285 |
11 |
s |
3-6985 |
3-5815 |
11 |
|
tt |
1-8825 |
1-705 |
11 |
3^ |
3-912 |
3-7955 |
11 |
|
U |
2-022 |
1-965 |
11 |
3f |
4-1255 |
4-0085 |
11 |
|
if |
2-16 |
2-042 |
11 |
4-340 |
4-223 |
11 |
COMPARATIVE PRESSURES.
299
Comparison of Pressures in Inches of Mercury, Feet of Water, and Pounds per Square Inch.
2 3 4 5 6 7 8 9 10 IT 12 13 14 15 Pounds per Square Inch.
300
GAS ENGINEER'S POCKET-BOOK.
30 Ibs. pressure per square inch equals about a head of 70 feet, with a velocity of 66 feet per second. Therefore, area of pipe x feet per second equals discharge per second.
Double pressure equals 1£ times delivery.
Four times length of main equals £ delivery.
Double the pressure on the district increases the leakage about 50 per cent.
Other authorities say loss by leakage is in direct proportion to the pressure.
Mr. Hill found at Wallasey a loss of 1-7 per cent, between the station meter and the gasholder outlet due to temperature, and as the " Sales of Gas Act" allows 2 per cent, fast, and 3 per cent. slow, in the meters, he suggests that £ per cent, should be allowed off leakage on this account.
With regard to district pressures it may be laid down as a safe rule that the lower the pressure can be kept, consistent with an efficient and proper supply, the lower will be the unaccounted-for gas.
Gas at the depth to which the mains are laid, say 2 feet as the average, the temperature would be between 1° and 2° higher than that of the air. According to the Meteorological Office the mean air temperature for the United Kingdom may be taken as 48*69° F., so that 50° F. may be taken to be the average temperature of the street-mains at a depth of two feet.
The mean rise of temperature between the main and the meter is 6£° ; some meters show more and some less. (Lewis T. Wright.)
Transmission of Gas of 0-55 Specific Gravity through Pipes and Bends (90°). (Nelson W: Perry.)
|
Inches Pres- sure. |
Cubic Feet. Delivered. |
Velocity of Flow in Feet per Second. |
Increase of Pressure per Bend. |
Total Increased Pressure for 25 Bends. |
Total Initial Pressure. |
|
1 |
12,500 |
4-0 |
0-0016 in. |
0-04 ill. |
1-04 |
|
2 |
18,000 |
6-0 |
0-0034 |
0-085 |
2-085 |
|
3 |
23,000 |
8-0 |
0-006 |
0-1495 |
3-15 |
|
4 |
25,500 |
8-8 |
0-0076 |
0-189 |
4-189 |
|
5 |
28,000 |
9-6 |
0-0086 |
0-215 |
5-215 |
|
6 |
32,000 |
11-0 |
0-0113 |
0-28 |
6-28 |
|
7 |
34,000 |
12-0 |
0-0135 |
0-34 |
7-34 |
|
8 |
36,000 |
12-5 |
0-0147 |
0-39 |
8-39 |
|
9 |
38,500 |
13-0 |
0-0158 |
0-4 |
9-4 |
|
10 |
40,000 |
14-0 |
0-0183 |
0-46 |
10-46 |
Maximum pressure should not exceed twenty-tenths on district where possible.
1 \ to 2 inches pressure at works may be sufficient if the distributing mains are of sufficient capacity, and the district fairly level.
NAPTHALENE.
301
Gas, after travelling ten miles, lias been found to lose only about 3 per cent, in illuminating power.
It is far cheaper to transmit the coal by railroad, and generate electricity on the spot, than to generate it and transmit the current through wires.
With ordinary town gas of 16 candle power, 3,000 H.P. can be sent one mile for an expenditure of 1 H.P. = 3V per cent, of the power conveyed.
Mr. Wright estimates the true loss as about 65 per cent, of the unaccounted-for gas ; later, by another method, at 75 per cent. ; and now, from such examinations of the results of the inferential as he has been able to make (from the observation of the amount of water absorbed by the gas passing through consumers' wet meters), it appears to him safe to say that the bulk of the unaccounted-for gas is actual loss from the distributing system, always, of course, assuming the meter registration to be reasonably correct.
Napthalene arises from the H of the gas passing through the main, by the action of the exosmose, and thus the carbon, deprived of its diluent, is deposited in its solid state. (Dr. Frankland.)
If this were the case napthalene would always be deposited, which is not the case.
Napthalene is found wherever there is a condensation of the aqueous vapour contained in the gas. If the aqueous vapour is removed from the gas, napthalene is not deposited under ordinary conditions of temperature and pressure. (Bremond.)
Napthalene is generally only found when mains or services are laid less than 1 foot from the surface of the ground.
Every deposit of napthalene equals a reduction of illuminating power in the gas.
Naptha dissolves napthalene.
No napthalene found iu mains since water gas used at Blackburn.
Napthalene is not likely to be found in mains if the gas contains more than 2 per cent, benzol. (Col. Sadler.)
Of all enrichers, benzene, for the average consumer of gas gives the greatest value for the money.
Toluene and xylene are better enrichers ; but their non- volatility precludes their employment. J
One gallon of beniol enriches 9,500 feet 1 candle, and 1 gallon of carburme will improve 2,800 cubic feet to the same extent. QJVlr. Hunt.)
The temperature at which benzol volatilizes is a convenient one as ordinary steam heat is all that is required.
The amount of benzol vapour which common coal gas can ner- manently retain, viz., over 50 grains per cubic foot at 0° C., is greater by far than anything required to enrich low-quality gas to anv reasonable extent. y
Benzol at a t-mperature of 70° to 80° C. will dissolve 2i to 2* Ibs
gall°D!
A Ib e
Between 7 and 9 grains of benzol vapour will improve 1 cubic foot of gas between 4 and 5 candles. (Dr. Bunte.)
302
GAS ENGINEER S POCKET-BOOK.
The results of disillumined gas plus benzene are —
0*0221 gramme per litre gives 1*3 candles
0-0385 0-0544 0-0630 0-0863 0-0881 0-1231
4-1
7-6
9-6
21-0
30-2
30-0
(Irwin.)
Benzene gives about -4 candles per gallon per ] ,000 cubic feet.
Benzol (chemically pure)
Benzol (90°)
Carburine (680 specific gravity) Common petroleum spirit (700 specific j
Gas enriched 1 Candle by
1 Gallon of the Liquid. . 13,300 cubic feet. . . 12,500 „ „ . . 5,700 „ „ Cavity) 4,300 „ „
In an enricher a carbon atom combined with H4 or H3 is useless ; a carbon atom combined with H2 possesses enriching power ; a carbon atom combined with Hx possesses two or three times the enriching power of the foregoing ; and a carbon atom combined only with other carbon atoms again possesses two or three times the enriching power of a carbon atom combined with H. (W. Irwin.)
By admitting alcohol vapour, in regulated amount, to the gas main, the illuminating power of the gas is unaffected thereby, though the freezing-up of the services is prevented. The alcohol is vaporized by steam or direct heating just before admission to the main, and the quantity is regulated according to the amount of gas passing per hour and the prevailing degree of cold. (Dr. J. Buel.)
Disillumined Gas and Heptane (prepared by Fractionating Petroleum
Spirit).
0-0528 gramme per litre gives 2-15 candles. 0-1010 „ „ „ 6-35 „
0-1516 „ „ ., 11-10 „
Napthalene is the cheapest and greatest enricher, but it cannot be supplied with gas from the gas-works because of its non- volatility. It could, however, be used for the street lamps with a carburetting apparatus, which would give 50 per cent, more light for a mere fraction. Were separate mains employed and water gas used in con- nection with napthalene, the cost of street lighting would be reduced to a minimum. (W. Irwin.)
In napthalene not more than 44 per cent, of the weight added to the gas is really utilized in emitting light.
The napthalene in the gas in street mains may be held in suspen- sion, by admitting gasolene into the main outlet pipe leading from the works to the street main system, by reason of its greater affinity for it than moisture has.
Napthalene melts at 174° F. and boils at 428° F.
NUMBER OF FEET FOR ONE PENNY.
303
|
TIT |
-- |
||||||||||
|
Diagram showing the number of feet for one penny at rates per 1,000. cubic ft. varying from i\ to 8/6. To use the diagram : — Find the price per thousand on the lower line, follow the corre- sponding vertical line upwards until it cuts the |
curved line, then carry the eye horizontally to the left, when the numbeiixif feet for one M , • ' .. .. MI u- r j |
i \ i K 3 |
i -i- |
|E |
1 |
E-- |
0 |
||||
|
Til |
TTT |
— ffl |
HUMBtlt OF CUBIC fCCT l-Olt OHf PCHH
304
GAS ENGINEER'S POCKET BOOK.
Comparison of Prices of Gas in Sterling and French Monies.
Price per 1,000 Cubic Feet.
I2/- I3/- I4/- IS/- l6/- I//- l8/- IQ/- 20/- 2I/- 22/- 23/-
90
So
J*
1 50
3
30
Price per 1,000 Cubic Feet in Shillings and Pence.
HELATIVE VALUES OF ILLUMINATING AGENTS.
305
Service Yielded by Ordinary Burners Consuming 16*5 Candle Gas.
(Professor Lewes, June, 1893.)
Burners. Flat flame No. 6
London Argaud Regenerative
Illuminating Value per
Cubic Foot of Gas.
. 2*5 candles. . . 2-1 „
. 1-9 ., . . 3-3 „
. 10-0
Relative Values of Illuminating Agents. (Dr. Letlieby.)
In respect to their vitiating and heating effects on the atmosphere, when burning so as to give the light of 12 standard sperm candles.
|
Thermal Units of Heat. |
Oxygen Consumed. |
Carbonic Acid Produced. |
Air Vitiated. |
|
|
Cubic Feet. |
Cubic Feet. |
Cubic Feet. |
||
|
Cannel Gas |
1-950 |
3-30 |
2-01 |
50-2 |
|
Common Gas . . |
2-780 |
5-45 |
3-21 |
80-2 |
|
Sperm Oil |
2-325 |
4-75 |
3-33 |
83-3 |
|
Benzol . . . |
2-326 |
4-46 |
3-54 |
88-5 |
|
Paraffin . |
3-619 |
6-81 |
4-50 |
112-5 |
|
Camphine . . . |
3-251 |
6-65 |
4-77 |
119-2 |
|
Sperm Candles |
3-517 |
7-57 |
5-27 |
131-7 |
|
Wax ., . . |
3-831 |
8-41 |
5-90 |
149-5 |
|
Stearic .', |
3-747 |
8-82 |
6-25 |
156-2 |
|
Tallow „ . . |
5-034 |
12-06 |
8-73 |
218-3 |
Gas Consumed and Carbon Dioxide Produced per Hour to Yield an Illumination of 48 Candles.
(Professor Lewes, June, 1893.^
|
Gas Consumed. |
CO 2 Produced. |
No. of Adults to Produce CO , |
|
|
Flat flame No, 6 |
19-2 |
10-1 |
16-8 |
|
)> r» » » • • • |
22-9 |
12-1 |
20-1 |
|
» » ± • |
25-3 |
13-4 |
22-3 |
|
London Argand . . . |
15-0 |
7-9 |
13-1 |
|
Regenerative . |
4-8 |
2-5 |
4-1 |
|
Paraffin Lamps . . . |
|
13-5 |
22-5 |
|
Candles, sperm |
— |
19-62 |
32-7 |
G.E.
306 GAS ENGINEER'S POCKET-BOOK.
Duty in Candles of Various Burners at 5 feet per Hour.
(j. H. Cox, Junior.)
Duty in Candles.
Standard Argand . . . , . . . 16
Public lamps, average 13£
Good batswing after 1 years use, rather dirty . « 10
Good batswing after being cleaned . . . 13£ Iron batswing. corroded and old . . . . ^\ Iron fishtail, corroded and old . . . 8£
Iron batswing, corroded and old . . . . 6 Iron batswing, corroded and old . . . 3|
Wasteful Argand , . 5J
Peebles' 5 feet regulator burner . . . « 1-H
Bray's No. 8 flat flame burner 14
Borrowdail's governor burner. . . . t 13£
Sugg's Christiania burner 14
A good unregulated burner under unnecessary
pressure 8
Same burner regulated 12 2
Number 1 Argand, at 5 cubic feet per hour . .16 Number 1 Argand turned down to 3 cubic feet . . 8
Wenham lamp ground glass shade, at 45° . . 22
Average of above 18 burners . . . 11^
Other Illuminants under Best Conditions. (J. H. Cox, Junior.) In candles per Id,
Electricity (incandescent), at \d. per hour per
8 candle lamp 3£
Candles — Palmatine candles 6 to 1 lb., at lOd. per pound, 9 inches long burning 1 inch per hour. Illuminating power corrected to 120 grains per hour, 1£ standard candles .
Oil — Petroleum burnt under best conditions in a 20 candle duplex lamp (oil at 1*. per gallon) 9-s
Burners when lighted use less gas than when fumed on and not lighted ; a No. 3 burner lighted consumes 3 cubic feet, unlighted 3i cubic feet per hour.
"Effects of different pressures on a No. 4 union jet burner :— Pressure in inches . . 0'5 1-0 1'5 2-0 2*5 3'0 Consumption, cubic feet 3'9 5-6 7'0 8-45 96 105 Unit efficiency, candles . 3-0 2-4 1-9 15 1'35 I'll
VITIATION OF AIR.
307
Carbon and Hydrogen Escaping Unconsumed per 100 parts C., Completely Burned. Ov- Thomson, 1890.)
|
Carbon. |
Hydrogen. |
|
|
Petroleum lamp, not burning at the full . „ „ with flame turned full on |
1-204 |
0-309 |
|
Argand gas flame |
— |
0-025 |
|
...... |
0-011 |
0-254 |
|
Bray burner, consuming 4 cubic feet per |
||
|
hour ....... |
1-112 |
0-095 |
|
Welsbach burner |
1-5 |
0-379 |
|
Marsh-Greenall's heating-stove burning : |
||
|
5-62 cubic feet per hour |
1-26 |
0-3 |
|
5-71 „ ., „ .... |
3-76 |
1-18 |
|
7-10 „„„.... |
9-74 |
1-21 |
|
Thos. Fletcher's heating stove : — |
||
|
with 8 Bunsen burners . . . . |
•4-33 |
2-46 |
|
burning 6*81 cubic feet per hour . |
6-63 |
2-0 |
|
with 20 Bunsen burners with asbestos |
||
|
and fire-clay back consuming 8*14 |
||
|
cubic feet per hour . . . |
13-89 |
1-17 |
|
Heating stove |
20-0 |
— |
|
Vitiates per Hour. |
Units of Heat Generated. |
|
|
Cubic Feet. |
||
|
An adult man .... |
215 |
190 |
|
Each cubic foot of gas burned . |
8-5 |
600 |
|
Each pound of oil burned . , " . ., „ candles burned . |
150 160 |
| 16,000 |
Daylight on a well exposed table equals 4*6 foot candles.
Minimum required for reading without fatigue equals 1 candle at Ifoot.
Minimum required for fluent reading equals 1-4 to 2-3 candles at 1 foot.
Minimum required for street lighting equals 0"09 candles at 1 foot.
(Cohn and Wybauw.)
The light from the edge of a petroleum lamp flame equals 62 to 63 per cent, of that from the flat side.
The reflective power of a whitewashed ceiling equals a loss of light of only 20 per cent. (H. E. Harrison.)
The intensity of illumination on a given surface is inversely as the square of the distance from the source of light.
The intensity of illumination which is received obliquely is pro- portional to the cosine of the angle which the luminous rays make with the normal to the illuminated surface.
x2
308 GAS ENGINEEB'S POCKET-BOOK.
Adults inhale about 1 pint of air at each breath and take 18 to 20 breaths a minute.
The heat evolved by a gas flame is the best of all ventilating mediums, provided a simple means is secured for conveying the products of combustion out of the room.
It is said that the injury done to books by gaslights is not due to the sulphur in the £,as but by what is called carbon oxysulphide, condensing on any object a foot or so below the ceiling.
If a chimney is properly constructed it may be used for a venti- lating flue, and be able to give a pull of one and half to two tenths of an inch vacuum, which is sufficient to convey away all the vitiated air from a room if the flue pipes arc large enough.
Temperature cf air in rooms should not be more than 10° higher at 1 foot from the ceiling than at 1 foot from the floor.
Two-tenths of an inch draught gives a velocity of air of about 6 feet per second.
Inflowing air should, if possible, be warmed to within 10° or 15° of the temperature of the room.
The rarer the atmosphere the larger the flame; the denser the atmosphere the smaller the flame.
When coal gas is burnt sulphur is liberated as sulphur dioxide, but this is not further oxidized to sulphuric acid (H2S04) unless the tem- perature falls so greatly that water is deposited. "
A certain amount of sulphurous acid is no doubt formed wherever gas is burnt, and this may, in the presence of moisture, be converted into sulphuric acid, but when ordinary ventilation is used, the amount must be very trifling.
Dust collected in rooms where no gas is burnt is found to contain an equal quantity of sulphates as that found in gas-lighted rooms.
No instance of imperfect combustion has been ever substantiated against lighting-burners, nor even against heating-burners of good class when employed under their normal working conditions. (L. T. Wright.)
C0? in gas has more effect on a flat flame than in an Argand in reducing the light, the depreciation being less the higher the candle power.
No trace of CO or acetylene was found in the products of combus- tion from Welsbach, Argand, and Bray burners. (Lancet.}
Two cubic feet H + 1 cubic foot 0 forms 2 cubic feet aqueous vapour.
By heating the air and gas before combustion, the carbon particles in the gas are liberated earlier and brought to a higher temperature, at the same time they are kept at this temperature for a longer period.
The burner tip should be of a non-conducting nature, as steatite, so as not to reduce the intensity of combustion.
In Argand burners the supply pipes to the ring are generally of smaller area than the sum of the areas of the holes in the latter so as to reduce the pressure at the point of consumption.
Angle at which the mean intensity of flat flame burners is obtained varies from 1-5° to 10-25°, average 4'68°. (A. C. Humphreys.)
PROPER HEIGHT OF LAMPS.
309
Sizes of Internal Pipes, Lead and Iron, According to Number of Burners Required, as Allowed by Blackpool Corporation Gas Department.
|
Internal Diameter of Pipe. |
Greatest Length Allowed. |
Greatest No. of Burners. |
Internal Diameter of Pipe. |
Greatest Length Allowed. |
Greatest No. of Burners. |
|
Inches. |
Feet. |
Inches. |
Feet. |
||
|
f |
20 |
3 |
1 |
80 |
40 |
|
30 |
6 |
u |
100 |
60 |
|
|
| |
40 |
12 |
H |
150 |
100 |
|
a 4 |
50 |
20 |
2 |
200 |
200 |
Light absorbed by clear glass globes . .12 percent.
., ,, „ engraved globes . .24
„ ., globe of ordinary pattern . 35
„ J, „ obscured all over . 40
„ „ white opal globe . . 60
„ „ painted opal globe . . 64
Clear glass prevents 10*57 of the light from passing through it, ground glass stops 29*48, smooth opal glass over 52'83, and ground opal more. 55-85.
Formula for determining the height of lamps for a known radius of lighting —
Ji=l J 2 = 0-7 I
The proper height of any light should be 0*7 of the area to be lighted by any one light. (Electrical Committee Chicago Exhibition.)
The proper height of any light should be such as to give an angle of 7° to the most distant point it is intended to serve. (Professor H. Robinson.)
For comparisons of lighting he reduces the various distances, etc., to a co-efficient.
Candle power of lamp X height of lamp in feet tlistance from lamp to farthest point served in feet 3
With Argand or flat flame burners free to the air, the distribution of light upon a circumscribing sphere of radius 1 is equal, but this is not the case with regenerative or incandescent burners. (W. Hy. Webber.)
Table of Lighting. (Deduced from R. Richards.)
Street lighting. Church ',' !
Theatre ,'J
Public halls lighting
Workshop ,.
Road or pavement .
Walls .
General .
Pew or reading desk
Auditorium
General area
candle foot.
2 to
310 GAS ENGINEER'S POCKET-BOOK.
Table of Lighting. (Deduced from E. Richards) — continued.
Workshop lighting Benches 3 J candle foot.
., ., . Optical or fine work . .5
Domestic ., Corridors, passages, halls, etc. f ., .,
., ., . Living rooms . . • • I •• „
„ ., Library, study, or bedroom . ± ., .,
„ „ . Table lighting ... 2 v
The sun's light equals about 5,600 candles placed at a distance of 30 centimetres.
The moon's light equals about ^jth candle placed at a distance of 3-65 metres.
The sun's light equals 5,500 candles placed at a distance of 12 inches (another authority).
Formula to Find the Intensity of Light any Distance.
Initial power of the light Intensity = -
Formula to find the Initial Intensity of any Light.
Initial intensity = intensity found at any point X distance of that point from the source of light 2.
Formula to find distance at which any Intensity will be found.
/Initial power of the light Distance = V - Intensity desired ^
Formula to find Intensity of Light falling upon a point in a horizontal plane from a source above it.
Illuminating power of source X vertical height above plane Slant distance3
German Experiments show that a light of 1 candle power can be seen 1*4 mile on a clear dark night, and TO mile on a rainy night.
American Experiments show that in clear weather a light of
1 candle power is visible at . . . .1 mile.
3 „ ., ., (with a binocular) 2 miles.
10 ., „ „ ,, ,. 4 „
20 „ „ „ (faintly) . . . 5 „
33 „ ., ., (easily) . .8 „
Dutch Experiments show that a light of
1 candle power is visible at 1 mile 3J „ ,. .. „ * 2 miles
VENTILATION".
311
A green light to be seen at
1 mile at sea must be of 2 candle power.
2 miles
15 61
106
The shade of green recommended is a clear blue green ; the shade of red a coppery red. Red lights show better than green ones at the same distance.
One light of whatever intensity is not perceptible to our eyes in presence of a light 64 times brighter. (Bouguer.)
The intensity of illumination which is received obliquely is pro- portional to the cosine of the angle which the luminous rays make with the normal to the illuminated surface. (Dr. Atkinson.) Freshly fallen snow reflects 78 per cent, of light. White paper ,, 70 ,, „
., sandstone „ 24 „ .,
Ordinary earth, road Q
surfaces, etc.
Old Rule for Numbers of Burners Required for Effective Lighting-
Floor area in square feet 50
Ventilation Notes.
Ventilation should be arranged so as .to change the air in a room in 10 minutes as a maximum.
With a 6-inch vertical flue 12 feet long the most economical burner to use is one of 1 cubic foot per hour capacity, this will remove 2,460 cubic feet of air per hour.
The maximum consumption of gas in a ventilating flue should not exceed 5 cubic feet per hour for each circular foot area of section.
The atmospheric and illuminating flame is the same in all cases where a large quantity of air has to be heated to a low temperature. The consumption of 1 cubic foot of gas in a ventilating shaft can be made to remove more than 2,400 times its own bulk.
Normal air contains 0'364 grains C00 per foot.
Air to be pure should not contain more than 7 grains C0a per cubic foot.
Adult expires 15 cubic feet of air per hour, containing 4£ per cent. C02 = -8 cubic feet per hour.
Air at 60° should not contain more than 5 grains moisture.
|
1 Adult. |
1 Cubic Foot Gas. |
|
|
Cubic feet of C02 per hour given off by Heat units given off by Grains per cubic foot of water vapour Cubic feet of air actually used by „ „ „ vitiated in an unventi lated room . |
0-8 480 200 15 1,200 |
0-5 620 440 60 800 |
312 GAS ENGINEER'S POCKET-BOOK.
Ventilation should be 2,000 to 3,000 cubic feet per hour.
About 3 cubic feet to 4 cubic feet per minute of air is required for each adult. Sleeping apartments should have about 1,000 cubic feet per occupant. Workshops and living rooms not less than 600 cubic feet per person.
For each lamp or gas burner from 30 to 60 cubic feet of air is required per hour.
A 4-inch shaft 8 feet long, with the help of a jet of gas burning £ to f of a cubic foot per hour, will aspirate upwards of 1,100 cubic feet of air per hour in a still atmosphere, and with further assistance of a wind moving across the ventilator at a velocity of 4£ feet per second, it will aspirate 3,126 cubic feet per hour.
A 6-inch similar cowl, with a burner consuming 4 cubic feet of gas per hour, will, in a still atmosphere, aspirate about 2.500 cubic feet of air per hour, and with the assistance of wind moving at the velocity of 9 feet per second it will aspirate 6,840 feet per hour. (W. Sugg.)
Professor Smithells concludes that when compounds of carbon and hydrogen meet oxygen the C is first oxidised and the H liberated, which is then converted into steam by oxidation. The light of the flame being due to carbon formed by the decomposition of hydro- carbons by the heat of the primary combustion, according to the equation :— 3 C2H4 = 2 CH, + 4 CH + 2 H2.
Professor Lewes believes that the H rapidly, and the methanes slowly, diffuse to the outside of the flame, and are burned, producing heat sufficient to raise the temperature of the gas to 1.000° C., at which temperature the unsaturated hydrocarbons and the higher saturated carbons and hydrogen compounds being decomposed into acetylene, the heat rising to 1.200° C. changes the acetylene into C and 0, and the C becoming incandescent gives off the light.
Gas-flames with an ample supply of primary air when in contact with incandescent surfaces, do not discharge combustible gases among the products of combustion.
Professor Macadam found that with 4*85 candle power per foot gas. the best value with a Welsbach S burner was 10'66 candle power per foot, with 7'12 candle power per foot gas it was 12-75 candle power per foot, and with 2-80 candle power per foot gas it was 13 '63 candle power per foot.
The loss by different glasses, etc., is shown as follows :
Clear glass 1 cubic foot = 12-81 candle power. Mica .... =12-81 „ Amber glass 1 cubic foot= 12-18 „ „
Ruby glass . . = 9-06 „ „
When gas gets much above 24 candle power, it is not advantageous to employ the ordinary form of Welsbach C burner as supplied by the company at the time (1895). (Professor W. I. Macadam.)
By a more perfect admission of gas and air in a Bun sen burner, a corresponding heat development ensues, and a light equal to 27 candles per cubic foot can be obtained with 16 candle gas and without a chimney with the Welsbach- Denayrouze burner.
COMPARATIVE COST OF DIFFERENT LIGHTS.
313
Number of Candle-power Hours which can be Provided at the Same Cost. (Prof. D. E. Jones.)
Wax ....
Stearine . . . . 77
Incandescent electric light 440
Coal gas (slit burner) . 625 Acetylene and air (slit
burner). . . . 716
Oil gas .... 1.660
Water gas and benzene . 1,666
Electric arc . : 2,322
Schulke's petroleum-gas
lamp Auer - Welsbach
with coal gas Auer - Welsbach
with water gas
burner burner
2,250 2.300
4.350
Comparative Cost of Different Illuminants (Germany).
Gas Argand burner 943d.
„ small Wenham burner 483d.
„ carburetted with napthalene, No. 2 Bray burner 574d.
„ Welsbach burner 305d.
Petroleum, large centre draught burner . . . 449d.
,. small burner 589d.
Electric glow lamp . 1954d.
The comparative cost of a duplex lamp, with paraffin at 8d. a gallon equals 5-63d. per 1,000 candles per hour.
The comparative cost of a Lamp Beige, with paraffin at 1*. a gallon equals 7'9d. per 1.000 candles per hour.
The comparative cost of Schulke regenerative lamp, with gas at 2s. 3d. per 1.000 feet equals 2-9^. per 1,000 candles per hour.
The comparative cost of Wenham regenerative lamp, with gas at 2s. 3d. per 1,000 feet equals 4-ld. per 1,000 candles per hour.
The comparative cost of ordinary flat flame burner equals S'3d. per 1,000 candles per hour. (L. T. Wright.)
Incandescent Electric Lamps.
|
Number of Hours , the Lamp lias been alight. |
Illuminating Power. |
Number of Hours the Lamp has been alight. |
Illuminating Power. |
|
0 |
14-8 |
453 |
10-8 |
|
96 |
14-0 |
520 |
11-5 |
|
168 |
13-3 |
612 |
10-5 |
|
307 |
11-5 |
709 |
10-5 |
|
357 |
11-8 |
761 |
10-5 |
314
Relative Cost of Illuminants.
Gas at 3.?. per 1.000 cubic feet (16 candle) equals 1.
Composite candles, each burning 136 grains per hour at Is. per Ib. equals 16-6.
Mould tallow candles, each burning 145 grains per hour at 6d. per Ib. equals 18-0.
Wax candles, each burning 165 grains per hour at Ls.per Ib. equals
Sperm candles, each burning 133 grains per hour at 2*. per Ib. equals 34'3.
Some 20 to 60 per cent, more sulphur is given off from paraffin lamps than from gas lamps.
Table Showing the Luminous Effect of a Square Centimetre of Flame Area. (M. Momrier.)
In a jet gas flame . . . . . 0'06 candle. „ an Argand burner .*,'.. 0'3 „ ., a Siemen's burner .... 0'6 „ „ incandescent electric lamps . . 30-0 ., „ the electric arc .... 480'0 „
Gas Stove Notes. (Lancet.*)
1. It is desirable that the stove should afford radiant heat only.
2. For this purpose some form of clay " fuel " is best.
3. Attention should be given to the packing of the " fuel " so as to avoid undue clogging or impeding the flow of the flames.
4. The stove should be supplied with separate burners with taps.
5. Some means of controlling the supply should be adopted. Governors or regulators are indicated.
6. A simple arrangement appears to be necessary by which undue drying of the warmed air may be avoided.
7. Indestructible enamel, or enamel little affected by the heat, should be used for coating the stove ; common paint, varnish or ordinary enamel should be avoided.
8. An efficient flue should in all cases be provided with gas fires, however, the flue pipe may be much smaller than the chimney required by coal fires.
9. The burner should be as far as possible noiseless. Pressure for gas stoves should not be less than four-tenths.
One volume of gas requires 5| volumes air for complete combustion.
Average mixture of gas and air in gas stove Bunsen burners is 1 to 2-3."
On a large scale one pound of meat can be cooked by 1 cubic foot of gas.
Gases in flues of gas stoves consist of about : — Oxygen, 12 per cent. ; Nitrogen, 84 per cent. ; C02 4 per cent.
40 cubic feet of gas in an average gas stove raised the temperature of a room 1,080 cubic feet, 5° F,
GAS STOVES.
315
Size of Pipes and Lengths Allowed for Gas Stoves by Blackpool Corporation Gas Department.
|
Average Inside Size of Oven. |
Distance of Stove from Meter. |
Pipe Required. |
||||
|
11 inches X 11 inches x 14 inches |
under 30 feet |
£ inch. |
||||
|
11 |
, Xll .. X14 |
if 60 |
A |
|||
|
14 |
. X 14 „ X 24 |
if 30 |
| |
|||
|
14 |
. X 14 .. X 24 |
if 60 |
1 |
|||
|
16J |
, X 15£ „ X 24 |
if 30 |
||||
|
m |
X 15£ „ X 24 |
if 60 |
1 |
|||
|
19 |
. X 18 ., X 24 |
if 30 |
1 |
|||
|
19 „ X 18 .. X 24 |
if 60 . |
H |
Connect all gas stoves with a large gas supply and with full-way taps and fittings. The chimney should be closed with a wrought iron plate with a hole in it to allow the flue of the gas stove to pass through.
One degree F.rise in temperature per 15'4 cubic feet gas consumed. Seven Ibs. coal required for same rise in temperature. (Professor Lewes.)
Total calorific value of gas is constant, whether Bunsen or luminous flames are used, if complete combustion is assured. The latter, however, must be kept sufficiently far from the object being heated so that the flame may not impinge upon its surface, or soot will be deposited, forming a non-heat-conducting layer, and so diminish the energy of the flame.
As regards the calorific value of the gas —
Carburetted water gas 145° )
Coal gas . . . 136° I per 4| cubic feet.
Mixed gas . . . 136°)
The permanent gas from the flue of a gas stove consists wholly of C02, N and 0. (Lancet.*)
Warming by Steam.
When the external temperature is 10° below freezing point, in order to maintain a temperature of 60° —
One square foot steam pipe for each 6 square feet glass in windows.
One square foot steam pipe for every 6 cubic feet of air escaping for ventilation per minute.
One square foot steam pipe for every 120 feet of wall, roof, or ceiling.
One cubic foot of boiler is required for every 2.000 cubic feet of space to be heated.
316
GAS ENGINEER'S POCKET-BOOK.
One horse-power boiler is sufficient for 50.000 cubic feet of space. Steam should be about 112°.
Heating. — 1 square foot of pipe surface heated to 200° will cause an average of 58° of heat in 150 cubic feet of air.
Heating Rooms. — 1 square foot of pipe surface is required for 80 cubic feet of space ; 1 cubic foot of boiler is required for 1.500 cubic feet of space ; 1 horse-power boiler is sufficient for 40,000 cubic feet of space.
Allow 1 square foot pipe surface per 120 feet wall and ceiling space for steam heating.
Allow 1 cubic foot for every 1 ,300 square feet wall surface when once warmed, but for preliminary heating about four times this amount is required, which also allows for ventilation.
The length of piping required to represent 1 square foot of heating surface —
36 inches of 1 inch wrought iron tubing to 1 square foot.
28 24 20 16 13 10
H H
2
2i
3
4
cast iron
The allowance would be 18 square feet of heating surface for living rooms, 13 feet for bedrooms, and 20 feet for halls for each 1,000 cubic feet of air in the place to be warmed. 1 inch main will supply up to 70 square feet. !£ inch main will supply up to 150 square feet. 1£ inch main will supply up to 300 square feet. 2 inch main will supply up to 600 square feet. 2£ inch main will supply up to 800 square feet. (G. Chasser.)
Percentage of Heat Evolved by Open Grates and Close Stoves, (D. K. Clark.)
|
Open Grates. |
Close Stoves. |
||
|
Heat carried up the chimney Radiated and conducted heat absorbed by the walls Heat lost by radiation and conduction externally, and heat lost by imper- |
43 per cent. 42 15 |
24 54 22 100 |
per cent. |
|
100 |
One pound of coal burnt in an ordinary grate requires for its combustion 300 cubic feet of air having a temperature of 620° F. (Sir Douglas Galton.)
HEATS OF FIRES.
317
Quantity of soot given off by a coal fire burning house coal of different qualities. — The amount is said to be on the average 6£ per cent, of the carbon in coal.
One volume gas requires 5J volumes air for complete combustion.
Dowson gas gives about 160 thermal units per cubic foot. Explosive force equals 1 to 3'8 for London gas.
To Prevent Stoves from Rusting. — Melt 3 parts lard with 1 part powdered resin ; add black lead if desired. Brush over in a thin coat.
Best Heats for Cooking.
Roasting pork Veal Pastry . „ puff
320° F. 320° 320° 340°
Beef . Mutton . Meat pies
310° F.
300°
290°
Heats of Different Fires.
Heat of a common wood fire = 800° to 1,1 40° F.
charcoal fire = 2,200° (about).
'., coal fire = 2,400°
Number of Grammes of Water Raised 1° through Equal Thickness of
Plate.
Copper Zinc . Iron
918 292 156
Tin .
Steel Lead
. 150
from 111 to 62 . 79
Breeze mixed with tar (40 gallons to the ton) does not produce a smoky fuel, and retains its shape.
The pitch used for agglomerating briquettes must not have had its binding qualities destroyed by the removal of its anthracene and heavy oils. A suitable pitch should soften at 75° C., melt at 100° to 120° C., remain hard at the normal temperature, and be capable of carriage in bulk. Its fracture should be dead black, conchoidal, clean and soft, without being greasy to the touch ; and the edges should not splinter when bitten by the teeth. So prepared, coke would burn as freely as bituminous coal. (W. Colquhoun.)
Tar for making pavements should be heated until converted to pitch that will harden on cooling. If overheated it loses its elas- ticity, and pavements made with it disintegrate rapidly. Refuse materials, such as clinkers, may be employed, and the pitch should be run straight from the boiler on to them, well mixed and laid and rolled at once. One barrel of boiled tar will make 50 cubic feet of pavement.
318
GAS ENGINEER'S POCKET-BOOK,
Proportions of Tar Concrete.
Aggregate 7
Sharp sand (clean) 2
Coal tar 6
Lias lime or Portland cement , 2
parts.
For the manufacture of tar paving it is usual to heat the stones over an iron plate, and then add tar which has been heated in open boilers, and the lighter oils evaporated at about 194° F. The time taken for this heating varies from four to twelve hours, as it is not desirable that the creosote oils should be distilled off.
Briquettes.
Good coal briquettes contain 5 per cent, of pitch if strongly pressed, or 7 to 8 per cent, if pressed with inferior or hard pitch.
Balloons.
The lifting power of a balloon is the difference between its weight and that of the air which it displaces.
1 cubic foot air weighs approximately -075 Ib.
1 „ hydrogen ., '005 .,
1 ., coal gas ., -043 „
1 ., air heated to 200° C. weighs approximately 'Oi'2 Ibs.
Therefore lifting power of coal gas = '075 - '043 = '032 Ib. for each cubic foot contained in the balloon.
The lifting power of hydrogen equals 60 to 70 Ibs. per 1,000 cubic feet, that of coal gas being about 35 Ibs.
Comparative Cost per Horse power per Hour. (Herr C. Korte.)
|
Size of Motor (horse-power). |
1 |
i |
1 |
2 |
3 |
4 | 6 |
||
|
Class of Motor. |
Hours daily. |
cl. |
d. |
d. |
d. |
d. |
d. |
d. |
|
Gas motor (gas at 3s. 4d. J |
5 |
7-92 |
5-7(5 |
3-72 |
2-88 |
2-52 |
2-40 |
2-28 |
|
per 1,000 cubic feet) . 1 |
10 |
5-76 |
4-08 |
2-64 |
2-88 |
2-04 |
1 -1)2 |
i-so |
|
Hydraulic motor (water at ) 6$d. per 1,000 gallons) I- |
5 10 |
12-12 10-5(5 |
10-80 9-84 |
9-72 9T2 |
9-00 8-64 |
— |
- |
— |
|
90 Ibs. . . . j |
||||||||
|
Electric motor (Berlin / |
5 |
8-88 |
7-22 |
5-88 |
5-04 |
4-68 |
— |
— |
|
tariff) . ... 1 |
10 |
7-56 |
6-48 |
5-40 |
4-80 |
4-44 |
— |
— |
|
Compressed air motor j |
5 |
15-00 |
11-64 |
8-40 |
6-96 |
6-00 |
5-40 |
4-32 |
|
(Paris tariff) . . . I |
10 |
13-08 |
10-44 |
7-68 |
6-48 |
5-84 |
5-16 |
4 'OS |
|
Steam motor, with coal at f |
5 |
4-20 |
2-88 |
2-40 |
2-04 |
i-so |
||
|
12s. Qd. per ton . . 1 |
10 |
__ |
|
2-88 |
2-04 |
1-68 |
1-44 |
1-32 |
|
Steam motor, with coal at f |
5 |
— |
— |
4-92 |
3-48 |
3-00 |
2-82 |
2-28 |
|
20s. per ton . . . 1 |
10 |
— |
— |
3-48 |
2-52 |
2-1(5 |
1-92 |
1-68 |
|
Hot air motor, with coal at f |
5 |
11-28 |
0-72 |
4-44 |
3-30 |
— |
— |
— |
|
12s. 6d. per ton |
10 |
6-48 |
4-08 |
2-76 |
2-16 |
~ |
~ |
WET METERS.
319
Consumption of Gas per head of Population.
London . 5,000 cubic feet. I France . 560 cubic feet. England . 2,450 ., Germany . 350 „
Approximate Composition of London Coal Gas, (Professor Lewes.)
H
Uusaturated hydrocarbons
Saturated hydrocarbons (CH-j)
CO
N
C02
0
Weight.
9-6
7-7
7-1 49-9 12-8 11-5
0-0
1-4= KKH)
Volume. . 52-0 f 3-0 ' \ 1-0 . 34-0 . 5-0 4-5 O'O
. 0-5 lOOl) Calorific value, 11,918 thermal units.
A weighted lever is better than a spring for keeping the pencil point up to the paper on a registering pressure gauge, but a weighted boat- shaped pen is better still.
Use a constant water level gauge in station meters, and keep a continuous stream of water running in.
A groaning station meter may be quieted by pumping in below the water line a hot water solution of soft soap.
Wet Meters.
|
Lights. |
Capacity of Drum. Cubic Feet. |
Capacity per Hour. Cubic Feet. |
Diameter of Inlet. |
Dimensions over all. |
|
Back Height. Width. to Front, |
||||
|
Inches. |
Inches. Inches. Indies. |
|||
|
2 |
•083 |
12 |
J |
151 x 10 X 11 |
|
3 |
•125 |
18 |
i |
17 X 12i x 8f |
|
5 |
•25 |
30 |
f |
18$ X 15J X 9l |
|
10 |
•5 |
60 |
21£ X 19i X 12i |
|
|
15 |
'75 |
90 |
1 |
24 X 21! X 14* |
|
20 |
1 |
120 |
l| |
26i x 23| X 15$ |
|
30 |
1-5 |
180 |
IT |
28| X 26£ X 17$ |
|
50 |
2'5 |
300 |
H |
28| X 26J- X 22i |
|
60 |
3 |
360 |
H- |
28f X 26 £ X 25 |
|
80 |
4 |
480 |
2 |
33f X 30£ X 28| |
|
100 |
5 |
600 |
2| |
38^ X 35J X 29y |
|
150 |
7-5 |
900 |
3 |
40 X 39 X 31f |
|
200 |
10 |
1,200 |
3 |
43! X 42i x 32.1 |
|
250 |
12-5 |
1,500 |
1 |
46 X 45£ X 32| |
|
300 |
15 |
1,800 |
o5 |
46 X 45i X 45| |
|
400 |
20 |
2,400 |
•1 |
49$ X 48! X 48i |
|
500 |
25 |
3,000 |
0 |
51i X 50J X 62J |
|
600 |
30 |
3,600 |
H |
51i X 50J X 65J |
320
GAS ENGINEERS POCKET-BOOK.
Dry Meters.
|
Lights.. |
Diameter of Inlet. |
Capacity per Revolution. |
Capacity per Hour. |
Dimensions over all. |
|
|
Back Height, Width. to Front. |
|||||
|
Inches. |
Cubic Feet. |
Inches. Inches. Inches. |
|||
|
2 |
i |
•083 |
12 |
14J X 10J X 7j |
|
|
3 |
.<•, 8 |
•125 |
18 |
15i x n .v x 8 |
|
|
5 |
f |
•16 |
30 |
17 x ia x 8f |
|
|
10 |
•3 |
60 |
19£ X 15 X 10£ |
||
|
15 |
1 |
•416 |
90 |
2H X 16 X 11§ |
|
|
20 |
1| |
*5 |
120 |
24" X 18J X 12| |
|
|
30 |
If |
•83 |
180 |
25J X 20.1 X 14 |
|
|
40 |
If |
1-25 |
240 |
29| X 23 X 17 |
|
|
50 |
1| |
1-428 |
300 |
32i X 25i X 21 |
|
|
60 |
If |
1-6 |
360 |
33-' X 21\ X 21 |
|
|
80 |
2 |
2-5 |
480 |
38 J X 3H X 22 |
|
|
100 |
2 |
2-857 |
600 |
40 J X 32£ X 23 £ |
|
|
120 |
31 |
4 |
3-3 |
720 |
4(U X 35J X 26 |
|
150 |
3 |
g |
5-0 |
900 |
48| X 38 X 27 |
|
200 |
3i |
1 |
6-6 |
1.200 |
50 J X 42} X 29 |
|
250 |
3* |
g |
7-3 |
1.500 |
56 X 45" X 32} |
|
300 |
4 |
y |
8-3 |
1,800 |
62 X 48 X 37 |
|
400 |
4 |
0> |
12-5 |
2,400 |
70 X 52 X 40 |
|
500 |
5 |
/. |
14-285 |
3.000 |
73| X 58 X 46 |
|
600 |
6 |
Ic |
22-222 |
3^600 |
77 X 58 X 50 |
|
800 |
7 |
J |
25-0 |
4,800 |
88 X 61 X 52 |
|
1000 |
8 |
* |
33-333 |
6.000 |
90 X 64 X 54 |
Standard Sizes of Unions for Connecting Gas Meters. (Board of Trade Standards Department.)
|
Boss. |
CAP. |
LINING. |
|||||
|
Size of Meter. |
Mean Diameter of External |
Number of Threads per |
Internal Diameter. |
Mean Diameter of Internal |
Number of Threads per |
Height of Cap. |
External Diameter to Outer 13oss. |
|
Screws. |
Inch. |
Screw. |
Inch. |
||||
|
Lights. |
Inches. |
Threads |
Inches. |
Inches. |
Threads |
Inches. |
Inches. |
|
1 &2 |
•88 |
19 |
•57 |
•84 |
19 |
•40 |
•55 |
|
3 |
•98 |
19 |
•67 |
•94 |
19 |
•50 |
•65 |
|
5 |
1-15 |
14 |
•83 |
1-10 |
14 |
•50 |
•81 |
|
10 |
1-45 |
11 |
1-05 |
1-40 |
11 |
•60 |
1-03 |
|
20 |
1-80 |
11 |
1-42 |
1-75 |
11 |
•60 |
1-40 |
|
30 |
2-05 |
11 |
1'55 |
2-00 |
11 |
•70 |
1*53 |
|
50 |
2-25 |
11 |
1-80 |
2-25 |
11 |
•70 |
1-75 |
|
60 |
2-45 |
11 |
2-00 |
2-40 |
11 |
•80 |
1-98 |
|
80 & 100 |
3-00 |
11 |
2-30 |
2-95 |
11 |
roo |
2-28 |
|
150 |
3-68 |
9 |
3-05 |
3-65 |
9 |
1-20 |
3-03 |
PREVENTING METERS FREEZING. 321
Meters.
Theoretical capacity of meters to pass gas is 6 feet per hour per light, though in practice larger quantities can be passed.
All meters should be fixed perfectly level.
The meter which is correct at a low pressure would be found to be slow at a high pressure.
In America the average tests of dry meters in one town was £ per cent, slow, and in another town £ per cent. slow.
Dry meters are liable to absorb the illuminants of the gas on the leathers which are always oily. Even the water in the photometer meter may have a thin stratum of oil on the surface which will some- times absorb the illuminants, and it ought, therefore, to be washed out occasionally, and filled only with distilled water having about 2 per cent, of pure glycerine in it.
To Keep Wet Meters from Freezing.
To prevent wet meters from freezing, pack horse manure round them, or
Turn off main cock and light a jet in house to consume the pressure in the pipes, unscrew plug and pour in, say, two table-spoonfuls of glycerine (for a three-light meter), allow a few minutes for the glycerine to come to the surface, and then shut off cock in house and turn main cock on again.
Use 5 per cent, pure glycerine in water for experimental and other meters.
Glycerine is said to have the effect of reducing the illuminating power of the gas when used with water in a gas meter.
Mixture used in E.A. Hydraulic Jacks to Prevent Freezing,
Methylated spirits ... 7 gallons.
Distilled water . . . . 3£ „
Mineral oil £ „
Carbonate of soda . . . . 250 grains.
Fluids transmit pressure equally in every direction.
A governor cone should be heavy enough to prevent oscillation, and a parabolic curve of a length equals twice the diameter.
To force gas down, say a mine, a jet of water may be sprayed into the top of pipe, and will cause an injector action according to the quantity of water in use.
Velocity of discharge due to head of water equals \/ head x 8 per second.
Area of governor bell sometimes ta_kejj at 20 times area of base of cone.
322
GAS ENGINEER'S POCKET-BOOK.
TESTING, Elementary Bodies.
|
Symbols. |
Combining Weights. |
Specific Gravity. |
Melting Points. C. |
|
|
Aluminium |
Al |
27-0 |
2-67 |
|
|
Antimony . . |
Sb |
120-0 |
6-71 |
425° |
|
Arsenic |
As |
74-9 |
( 5-9 |
|
|
Barium . . |
Ba |
136-8 |
4-0 |
|
|
Beryllium . |
Be |
9-2 |
||
|
Bismuth . . |
Bi |
208-0 |
9-8 |
270° |
|
Boron |
B |
11-0 |
2-69 |
|
|
Bromine . . |
Br |
79-75 |
2-966 |
|
|
Cadmium . |
Cd |
111-9 |
8'65 |
315° |
|
Caesium . . |
Cs |
133-0 |
||
|
Calcium . |
Ca |
39-9 |
1-58 |
|
|
Carbon . . . |
C |
11-97 |
||
|
Cerium |
Ce |
139-9 |
||
|
Chlorine . . |
Cl |
35-37 |
||
|
Chromium |
Cr |
52-1 |
7-3 |
|
|
Cobalt.. . . |
Co |
58-6 |
( 7-81 1 8-5 |
|
|
Copper |
Cu |
63-1 |
8-93 |
1090° |
|
Didymium . |
D |
142-0 |
||
|
Erbium |
E |
166-0 |
||
|
Fluorine . . |
F |
19-1 |
||
|
Gallium . |
G |
69-8 |
— |
+ 30° |
|
Gold . . . |
An |
196-2 |
19-3 |
|
|
Hydrogen . |
H |
1-0 |
•06926 |
|
|
Indium. . . |
In |
113-4 |
7-42 |
|
|
Iodine |
I |
126-53 |
4-95 |
|
|
Iridium . . |
Ir |
192-7 |
22-38 |
|
|
Iron . |
Fe |
55-9 |
7-8 |
1050° to 1600° |
|
Lanthanum . . |
La |
138-0 |
||
|
Lead . |
Pb |
206-4 |
11-35 |
3343 |
|
Lithium . . |
Li |
7-01 |
0-594 |
|
|
Magnesium |
Mg |
24-3 |
1-74 |
|
|
Manganese Mercury . . |
Mil Hg |
55-0 199-8 |
8-01 13-59593 |
at 0° C. - 40° |
|
Molybdenum |
Mo |
95-8 |
||
|
Nickel |
Ni |
58-6 |
8-8 |
|
|
Niobium . . |
Nb |
94-0 |
||
|
Nitrogen . |
N |
14-01 |
•97137 |
|
|
Osmium . . |
Os |
198-6 |
22-5 |
21-4° |
|
Oxygen . |
0 |
15-96 |
1-10563 |
|
|
Palladium . . |
Pd |
106-2 |
11-4 |
|
|
Phosphorus |
P |
30-96 |
1-77 |
AIR, GAS, AND WATER. Elementary Bodies — continued.
323
|
Symbols. |
Combining Weights. |
Specific Gravity. |
Melting Points. C. |
|
|
Platinum . . |
Pt |
194-5 |
21-5 |
|
|
Potassium . |
K |
39-04 |
0-865 |
62-5° |
|
Rhodium . . |
Rh |
104-1 |
12-1 |
|
|
Rubidium . |
Rb |
85-2 |
1-52 |
|
|
Ruthenium . . |
Ru |
103-5 |
12-29 |
|
|
Scandium . |
Sc |
44-0 |
||
|
Selenium . . |
Se |
78-0 |
4-3 |
|
|
Silver |
Ag |
107-66 |
10-5 |
1000° |
|
Silicon . . . |
Si |
28-0 |
||
|
Sodium |
Na |
22-99 |
0-974 |
95-60° |
|
Strontium . . |
Sr |
87-2 |
2-54 |
|
|
Sulphur . |
S |
31-98 |
2-00 |
|
|
Tantalum . . |
Ta |
182-0 |
||
|
Tellurium . |
Te |
125-0 |
6-25 |
|
|
Terbium . . |
Tb |
148-5 |
||
|
Thallium . |
Tl |
203-6 |
11-85 |
|
|
Thorium . „ |
Th |
231-5 |
||
|
Tin . . ';.; |
Sn |
117-8 |
7-29 |
235° |
|
Titanium . '..', |
Ti |
48-0 |
||
|
Tungsten . |
W |
184-0 |
||
|
Uranium . . |
u |
240-0 |
18-4 |
|
|
Vanadium |
V |
51-2 |
||
|
Ytterbium . . |
Yb |
173-2 |
||
|
Yttrium . |
Y |
89-0 |
||
|
Zinc . . . |
Zn |
65-1 |
6-8 to 7-2 |
433° |
|
Zirconium . |
Zr |
90-0 |
(In the case of gases, air = 1. ,. ,, ,, i, solids, water = 1.) |
Air, Gas and Water.
Pressure of atmosphere = 14-7 Ibs. per square inch = 2116-8 Ibs. per square foot.
Pressure of atmosphere equals 29-9 inches of mercury at sea level. ., „ „ 33-9 feet of water at sea level.
29 cubic feet of coal gas equals 1 Ib. approximately.
1 cubic foot of air at 62° F. equals -076 Ibs.
Gas or air expands 5^nd of its bulk at 32° F. for each degree F.
Water is at its maximum density at 39*2° F. (4°"C.) and expands ith part of its bulk on freezing.
Centre of pressure f rds depth from surface.
1 litre of fresh water =1 kilogramme = -001 cubic metre = '22 gallons = 2*2 Ibs. = '0353 cubic feet = 61 cubic inches.
1 ton of fresh water equals 1,016 kilogrammes, 1'0165 cubic metres, 1,016 litres.
1 ton of fresh water = 35-9 cubic feet = 224 gallons.
1 cubic metre of fresh water =1,000 litres = 1,000 kilogrammes. 35-316 cubic feet = 220 gallons = 2,200 Ibs.
1 cubic foot of fresh water = 62-425 Ibs. = -557 cwts. = -028 tons.
y 2
324
GAS ENGINEER'S POCKET-BOOK.
1 cubic foot of fresh water equals 6-24 gallons, or" salt water 64 Ibs.
1 cubic inch of fresh water = '03612 Ibs. = -003612 gallons.
1 gallon of fresh water = 10 Ibs. = '16 cubic feet.
1 cvvt. of fresh water = 1*8 cubic feet= 11-2 gallons.
Head of water in feet equals pressure in Ibs. per square inch X 2*307.
Pressure in Ibs. per square inch equals height in feet X '4335.
Pressure of a Column of Water per Square Inch and per Square Foot in Lbs.
|
Head. |
Pressure per Square Inch. |
Pressure per Square Foot. |
Head. |
Pressure per Square Inch. |
Pressure per Square Foot. |
|
Inches. |
Lbs. |
Lbs. |
Feet. |
Lbs. |
Lbs. |
|
A |
•260 |
25 |
10-82 |
1562-4 |
|
|
1 |
•520 |
30 |
12-99 |
1874-9 |
|
|
1-041 |
35 |
15-16 |
2187-4 |
||
|
JL |
1-562 |
40 |
17-32 |
2499-8 |
|
|
& |
2-083 |
45 |
19-49 |
2812-3 |
|
|
TO |
... |
2-604 |
50 |
21-65 |
3124-8 |
|
A |
3-124 |
55 |
23-82 |
3437-3 |
|
|
& |
3-645 |
60 |
25-99 |
3749-8 |
|
|
| |
4-166 |
65 |
28-15 |
4062-2 |
|
|
10 |
4-687 |
70 |
30-40 |
4374-7 |
|
|
1 |
•0362 |
5-208 |
75 |
32-48 |
4687-2 |
|
2 |
•0723 |
10-416 |
80 |
34-65 |
4999-7 |
|
3 |
•1085 |
15-624 |
85 |
36-82 |
5312-2 |
|
4 |
•1446 |
20-833 |
90 |
38-98 |
5624-6 |
|
5 |
•1808 |
26-040 |
95 |
41-15 |
5937-1 |
|
6 |
•217 |
31-248 |
100 |
43-31 |
6249-6 |
|
7 |
•253 |
36-457 |
110 |
47-64 |
6874-6 |
|
8 |
•289 |
41-666 |
120 |
51-98 |
7499-5 |
|
9 |
•325 |
46-872 |
130 |
56-31 8124-5 |
|
|
10 |
•362 |
52-08 |
140 |
60-64 8749-4 |
|
|
11 |
•398 |
57-29 |
150 |
64-97 |
9374-4 |
|
12 |
•434 |
62-5 |
200 |
86-63 |
13124 |
|
Feet. |
250 |
108-29 |
16249 |
||
|
2 |
•86 |
125-0 |
300 |
129-951 |
19374 |
|
3 |
1-30 |
187-5 . |
350 |
151-61 |
22499 |
|
4 |
1-73 |
250-0 |
400 |
173-27 |
26248 |
|
5 |
2-16 |
312-5 |
450 |
194-92 |
29373 |
|
6 |
2-59 |
375-0 |
500 |
216-58 j 32498 |
|
|
7 |
3-03 |
437-5 |
600 |
259-90 |
38748 |
|
8 |
3-46 |
500-0 |
700 302-22 |
45622 |
|
|
9 |
3-89 |
562-5 |
800 i 346-54 52496 |
||
|
10 |
4-33 |
624-9 |
900 |
389-86 58746 |
|
|
15 |
6-49 |
937-4 |
1000 |
433-18 |
64996 |
|
20 |
8-66 |
1249-9 |
To Bend Glass Tubes. (Spon.)
If a sudden bend is wanted, heat only a small portion of the tube to a dull red heat, and bend it with the hand held at the opposite ends. If the bend is to be gradual, heat an inch or two of it in length
• SATURATED HYDROCARBONS.
325
previous to bending it. If a gradual bend on the one side and a sharp one on the other, as in retorts, a little management of the tube in the flame, moving it to the right and left alternately at the same time as it is turned round, will easily form it of that shape. In bending glass, the part which is to be concave is to be the part most heated. An ordinary gas flame is quite sufficient* to bend glass by, but that of a spirit lamp is better.
Series I. — Paraffin Series, Marsh Gas. Saturated Hydrocarbons.
(E. L. Price.) Generic Formulae CnH2n -f- 2.
|
! |
Illumina- |
Volume of |
|||
|
Name of Hydrocarbon. |
Formula. |
Boiling Point |
Specific Gravity Water =1. |
ting Power. Candles, per 5 Cubic |
Gas from 1 Gallon GO°F. 30 Inches |
|
Feet. |
Barometer. |
||||
|
Methane . |
CH4 |
gas |
gas |
5-0 |
|
|
Ethane |
C2H6 |
gas |
gas |
35-0 |
|
|
Propane . |
C3H8 |
gas |
gas |
53-9 |
|
|
Butane1 |
C4H10 |
31° |
•6 |
— . |
37 |
|
Pentane . |
C«HH |
98°— 102° |
• 626620.6 P. |
|
31 |
|
Hexane |
CgH^ |
156° |
•663620'6 F. |
|
27 |
|
Heptane . |
C7H16 |
209° |
•70032° F. |
|
25 |
|
Octane |
CeHig |
258° |
.719320 F. |
|
22 |
|
Nonane |
C9H2o |
297° |
• 728560-5 F. |
|
20 |
|
Decane |
C10H22 |
331°— 334° |
.739660.5 F. |
. . |
18 |
|
Endecane . |
^11^24 |
356°_359° |
• 765610 F. |
|
17 |
|
Dodecane . |
C^HSJS |
392°— 395° |
•757640.4 F. |
— |
16 |
Series II. — Olefine Series, Saturated Hydrocarbons. (E. L. Price.) Generic Formula CnH2n.
|
Name of Hydrocarbon. |
Formula. |
Boiling Point F. |
Specific Gravity Water =1. |
Illumina- ting Power. Candles, per 5 Cubic Feet. |
Volume of Gas from 1 Gallon 60°F. 30 Inches Barometer. |
|
Ethylene . Propylene . Butylene . Pentylene . Hexylene.. Heptylene. Octylene . |
C2H4 C3H6 C4H8 C5H10 CGH12 C7H14 C8H16 |
gas gas gas 91°— 108° 154°— 158° 205° . 257° |
gas gas gas •655600 F. •699320 *'• •739630.5 F. .723620.6 F. |
68'54 123-05 |
33 30 27 23 |
Ordinary coal gas of 15 to 16 candle power contains about 2 per cent, benzene.
The effect of washing gas with mineral oil of '840 specific gravity is to reduce the illuminating power of the gas by about 50 per cent.
The stability of nearly all hydrocarbons is destroyed when subjected to temperatures above 2,000° F. (B. H. Thwaite.)
326
GAS ENGINEER'S POCKET-BOOK.
Bromide of potassium or concentrated sulphuric acid will absorb unsaturated hydrocarbons, but does not affect in diffused daylight the gaseous members of the saturated hydrocarbons.
A piece of rag moistened with a mixture of terebene, linseed oil, and turpentine, and rolled into a ball, rose in temperature from 20° C. .to 87° C. in the first hour, and began to fume ; and in the next hour increased to 310° C., fuming strongly ; half-an-hour later the rag burnt at a temperature of 360° C. (T. Wilton.)
Corks freshly cut have been found to contain an appreciable quantity of ammonia, and may cause errors in gasworks analysis.
Elastic Force or Tension of Aqueous Vapour in Inches of Mercury.
|
Temp. |
Temp. |
Force. |
Force. |
Temp. |
Temp. |
Force. |
Force. |
|
Fahr. |
Cent. |
Inches. |
M.m. |
Fahr. |
Cent. |
Inches. |
M.m. |
|
32°0 |
0° |
•1-81 |
4-6 |
67 |
19-4 |
•662 |
1(5-8 • |
|
33 |
0'55 |
•188 |
4-8 |
68 |
20-0 |
•685 |
17-391 |
|
34 |
1-1 |
•196 |
5-0 |
69 |
20-5 |
•709 |
17-9 |
|
35 |
1-65 |
•204 |
5-2 |
70 |
21-1 |
•733 |
18-6 |
|
36 |
2-2 |
•212 |
5-4 |
71 |
21-65 |
•758 |
19-25 |
|
37 |
2-75 |
•220 |
5-6 |
72 |
22-2 |
•784 |
19-9 |
|
38 |
3-3 |
•229 |
5-8 |
73 |
22-75 |
•811 |
20-55 |
|
39 |
3-85 |
•238 |
6-05 |
74 |
23'3 |
•839 |
21-3 |
|
40 |
4-4 |
•248 |
6-3 |
75 |
23-85 |
•868 |
21-95 |
|
41 |
5° |
•257 |
6-534 |
76 |
24-4 |
•897 |
22-7 |
|
42 |
5-5 |
•267 |
6-75 |
77 |
25-0 |
•927 |
23-5 |
|
43 |
6-1 |
•278 |
7-0 |
78 |
25-5 |
•958 |
24-3 |
|
44 |
6-6 |
•288 |
7-3 |
79 |
26-05 |
•990 |
25-05 |
|
45 |
7-15 |
•299 |
7-55 |
80 |
26-6 |
•023 |
25-9 |
|
46 |
7-7 |
•311 |
7-9 |
81 |
27-15 |
•057 |
26-75 |
|
47 |
8-25 |
•323 |
8-15 |
82 |
27-7 |
•092 |
27-6 |
|
48 |
8-8 |
•335 |
8-5 |
83 |
28-25 |
•128 |
28-45 |
|
49 |
9-45 |
•348 |
H-85 |
84 |
28-8 |
•165 |
29-4 |
|
50 |
10° |
•361 |
9-165 |
85 |
29-45 |
•203 |
30-55 |
|
51 |
10-55 |
•374 |
9-5 |
86 |
30-0 |
•242 |
31-548 |
|
52 |
11-11 |
•388 |
9-9 |
87 |
30-55 |
•282 |
|
|
53 |
11-65 |
•403 |
10;25 |
88 |
31-1 |
•324 |
|
|
54 |
12-2 |
•418 |
10-6 |
89 |
31-65 |
•366 |
|
|
55 |
12-75 |
•433 |
10-95 |
90 |
32-2 |
•410 |
|
|
56 |
13-3 |
•449 |
11-4 |
91 |
32-75 |
•455 |
|
|
57 |
13-85 |
•466 |
11-8 |
92 |
33-3 |
•501 |
|
|
58 |
14-45 |
•482 |
12-25 |
93 |
33-85 |
•548 |
|
|
59 |
15° |
•500 |
12-7 |
94 |
34-4 |
•597 |
|
|
60 |
15-55 |
•518 |
13-15 |
95 |
35-0 |
•647 |
|
|
61 |
16-05 |
•537 |
13-55 |
96 |
35-5 |
•698 |
|
|
62 |
16-06 |
•556 |
14-1 |
97 |
36-05 |
•751 |
|
|
63 |
17-15 |
•576 |
14-55 |
98 |
36-6 |
•805 |
|
|
64 |
17-7 |
•596 |
15-1 |
99 |
37-15 |
•861 |
|
|
65 |
18-3 |
•617 |
15-7 |
100 |
37-7 |
•918 |
|
|
66 |
18-9 |
•639 |
16-2 |
WEIGHT OF AQUEOUS VAPOUR.
327
Volume of 1 Ib. Air at Atmospheric Pressure equals 147 Ibs. per Square Inch.
|
Tempera- ture. |
Volume |
Tempera- ture. |
Volume. |
Tempera- ture. |
Volume. |
|
Degrees Fahr. |
Cubic Feet. |
Decrees Ffehr. |
Cubic Feet. |
Degrees Fahr. |
Cubic Feet. |
|
0 |
11-583 |
230 |
17-362 |
525 |
24-775 |
|
32 |
12-387 |
240 |
17-612 |
550 |
25-403 |
|
40 |
12-586 |
250 |
17-865 |
575 |
26-031 |
|
50 |
12-840 |
260 |
18-116 |
600 |
26-659 |
|
62 |
13-141 |
270 |
18-367 |
650 |
27-915 |
|
70 |
13-342 |
280 |
18-621 |
700 |
29-172 |
|
80 |
13-593 |
290 |
18-870 |
750 |
30-428 |
|
90 |
13-845 |
300 |
19-121 |
800 |
31-685 |
|
100 |
14-096 |
320 |
19-624 |
850 |
32-941 |
|
120 |
14-592 |
340 |
20-126 |
900 |
34-197 |
|
140 |
15-100 |
360 |
20-630 |
950 |
35-453 |
|
160 |
15-603 |
380 |
21-131 |
1,000 |
36-710 |
|
180 |
16-106 |
400 |
21 634 |
1,250 |
42-990 |
|
200 |
16-606 |
425 |
22-262 |
1,500 |
49-274 |
|
210 |
16-860 |
450 |
22-890 |
2,000 |
61-836 |
|
212 |
16-910 |
475 |
23-518 |
2,500 |
74-400 |
|
220 |
17-111 |
500 |
24-146 |
3,000 |
86-962 |
To Find the Weight of Aqueous Vapour in Air.
(1) Weigh calcium chloride in a small basiu ; cover the basin with a bell jar. Suppose the bell jar contains 1 cubic foot of air, weigh the basin after some time. The increase in weight will be the amount of aqueous vapour in 1 cubic foot of air.
(2) Place calcium chloride, or pumice-stone dipped in strong sulphuric acid, in tubes (both substances absorb aqueous vapour). Weigh the tubes ; then pass 20 gallons of air through them. The increase in weight equals the amount of aqueous vapour in 20 gallons. This forms a chemical hygrometer.
The maximum pressure of a vapour depends upon temperature and the kind of liquid used.
At different temperatures the maximum pressure of water vapour has been carefully determined.
|
Temperature C. |
Pressure in Milli- metres. |
Temperature C. |
Pressure in Milli- metres. |
|
—32° |
0-320 |
15° |
12-699 |
|
—20 |
0-927 |
18 |
15-357 |
|
—10 |
2-093 |
20 |
17-391 |
|
0 |
4-600 |
50 |
91-981 |
|
4 |
6-097 |
70 |
233-093 |
|
10 |
9-165 |
90 525-450 |
|
|
12 |
10-457 |
100 |
760-000 |
328 GAS ENGINEER'S POCKET-BOOK.
Weight of 1 cubic foot dry air at 60° F. and 30 inches press of mercury is about 537 grains.
Composition of the Atmosphere.
By volume oxygen = 20'8, by weight = 23 „ nitrogen = 79'2, „ =77
It also contains a little ammoniacal gas, and from 3 to 6 parts in 10,000 of its volume of C02.
Carbon dioxide in atmosphere equals about 4 volumes per 10,000 of air.
1 cubic foot water at ordinary temperature and pressure dissolves 1 cubic foot C02.
The higher the temperature, the greater the amount of aqueous vapour held in suspension in the gas.
The corrected volume of dry gases for both temperature and pressure equals
observed volume X observed pressure X 17*33 observed temperature -f- 460
because the product of the volume and pressure of a gas is pro- portional to the absolute temperature. The density of liquid air is 910. (Dewar.)
Minimum Quantity of Oxygen that will Support Combustion. (Professor Clowes.)
Paraffin flame 16'6 per cent, oxygen.
Candle „ 15-7 „ „
Methane „ 15«6
CO „ 13-35 „
Coal gas „ 11-35 „
Hydrogen „ 5-5 „ „
The quantity of moisture in coal gas saturated 20° C. and 760 millimetres equals 2 per cent, which has the effect of reducing the illuminating power 3-3 per cent.
To Find the Speed of Sound in Air.
Let A = distance between the observer and the cannon in feet. B = seconds that elapse between seeing the flash and hearing
the report. C = feet per second.
EXPLOSIVE MIXTURES.
329
Force of Explosive Mixtures of Air and Glasgow Coal Gas. (Dugald Clerk.)
|
Mixture. |
Maximum Pressure of Explosives |
Time of Explosion. |
|
|
Gas. |
Air. |
Square Inch. |
|
|
. 1 volume |
13 volumes |
52 |
0-28 seconds. |
|
1 „ |
11 „ |
63 |
0-18 „ |
|
9 „ |
69 |
0-13 „ |
|
|
1 ., |
7 „ |
89 |
0-07 „ |
|
1 n |
5 „ |
96 |
0-05 „ |
Heat of explosion of gun cotton = 2650° C. = 4802° F. Explosive mixtures are more readily kindled upwards by a flame placed below them, than downward by one placed above them.
limiting Explosive Mixtures of Gases and Air. (Professor Clowes.)
|
Upward Kindling. |
Downward Kindling. |
||
|
Methane Coal gas Water gas Hydrogen CO Ethylene |
Per cent. Gas. 5 to 13 5 to 28 9 to 55 5 to 72 13 to 75 4 to 22 |
Per cent. Gas. 6 9 |
Per cent. Gas. 11 22 |
Coal gas, horizontal tube, 10'3 per cent, to 23 per cent. (L. T. Wright.)
10-3 per cent, of coal gas (18'75 candles and -45 specific gravity (air equals 1)) and 89'7 per cent, air is the lowest limit of an explosive mixture.
23 per cent, coal gas as above and 77 per cent, air is the highest limit. (L. T. Wright.)
The limiting percentages of explosive gaseous mixtures are : — For methane, 5 and 13 ; for hydrogen, 5 and 72 ; for carbon monoxide, 13 and 75 ; for ethylene, 4 and 22 ; for water gas, 9 and 55 ; for coal gas, 5 and 28. It was also proved that many mixtures which were outside, but close to, the above limits, and which could not be fired from above could be fired from below.
An exceedingly small quantity of coal dust in air is sufficient to cause an explosion.
330
GAS ENGINEER'S POCKET-BOOK.
Expansion by Heat and Melting Points (F.).
|
Expansion. |
Melting point in degrees F. |
||
|
1° 1 Part in |
180° 1 Part in |
||
|
Fire brick .... |
365,220 |
2,029 |
|
|
Granite •• . * . from |
187,560 |
1.042 |
|
|
„ ... to |
228,060 |
1,387 |
|
|
Glass rod . ... |
221,400 |
1,230 |
|
|
„ tube . . . ' . |
214,200 |
1,190 |
|
|
„ crown . . |
211,500 |
1,175 |
|
|
„ plate . ' . "." |
209.700 |
1,165 |
|
|
Platina |
208^00 |
1,160 |
4,593 |
|
Marble, granular white dry |
173,000 |
961 |
|
|
„ „ ,, moist |
128,000 |
711 |
|
|
„ „ black com- |
|||
|
pact . . " ;V '?'.' ' |
405,000 |
2,250 |
|
|
Antimony . . . . |
166,500 |
925 |
883 |
|
Cast iron .... |
162,000 |
900 |
1,920 to 2,800 |
|
Slate |
173,000 |
961 |
|
|
Steel . . . . - . blistered . . . |
151,200 159,840 |
840 888 |
2.370 to 2,550 |
|
untempered |
167,400 |
930 |
|
|
tempered yellow . . |
131,400 |
730 |
|
|
hardened . . . |
146,800 |
816 |
|
|
annealed . . . |
147,600 |
820 |
|
|
Iron, rolled |
149,940 |
833 |
3,000 to 3,500 |
|
, soft forged . . . |
147,420 |
819 |
|
|
, wire .... |
146,340 |
813 |
|
|
Bismuth . . . . |
129,600 |
720 |
500 |
|
Gold, annealed . . . |
123,120 |
684 |
2,058 |
|
Copper . . average |
104,400 |
580 |
1,975 |
|
Sandstone . . . |
103,320 |
574 |
|
|
Brass . . average |
97-,740 |
543 |
1,853 |
|
„ wire. |
94,140 |
523 |
|
|
Silver |
95,040 |
528 |
1,866 |
|
Tin . . . average |
87,840 |
488 |
443 |
|
Lead . . . average |
62,180 |
351 |
612 |
|
Pewter .... |
78,840 |
438 |
|
|
Zinc (most of all metals) . |
61,920 |
344 |
680 to 772 |
|
White pine . . . . |
440,530 |
2.447 |
LBS. WATER HEATED AND C02 PRODUCED.
331
Lbs. Water Heated and C02 Produced from Various Gases.
(Letheby.)
|
Per Ib. |
Lbs. of Water Heated, |
|||||
|
1° F. |
||||||
|
O |
Air |
C0a |
Per |
PPV Ih |
||
|
Re- |
Viti- |
Pro- |
Per Ib. |
Cubic |
1:61 ID. O nocwl |
|
|
quired. |
ated. |
duced. |
Foot. |
\J US6U. |
||
|
Cubic Feet. |
Cubic Feet. |
Cubic Feet. |
Lbs. |
Lbs. |
Lbs. |
|
|
H. . . |
93-4 |
467 |
|
62,030 |
329 |
7,754 |
|
Marsh gas . |
47-2 |
826 |
23-6 |
23,513 |
996 |
5,878 |
|
Olefiant gas . |
40-5 |
878 |
27-0 |
21,344 |
1,585 |
6,225 |
|
Propylene . . . Butylene |
40-5 40 -5 |
878 878 |
27-0 27-0 |
21,327 21,327 |
2,376 3.168 |
6,220 6,220 |
|
Acetylene . . . |
36-3 |
909 |
291 |
18,197 |
Mol |
5,914 |
|
Benzole |
36-3 |
909 |
29-1 |
18,197 |
3,860 |
5,915 |
|
C02 |
6-7 |
371 |
13-5 |
4,325 |
320 |
7,569 |
|
CSa .... |
14-9 |
689 |
5-0 |
6,120 |
1,239 |
4,845 |
|
H2S |
16-7 |
630 |
— |
7,444 |
671 |
5.271 |
|
Cyanogen |
14-5 |
435 |
14-5 |
6,712 |
925 |
5,142 |
|
Coal gas (common) . . |
37-5 |
618 |
17-6 |
21,060 |
650 |
6,816 |
|
„ „ (cannel) |
31-0 |
698 |
220 |
20,140 |
760 |
6,503 |
|
Wood spirit . . . |
25-3 |
422 |
11-8 |
9,547 |
819 |
6,363 |
Lbs. Water Heated and CO* Produced from Various Substances.
(Letheby.)
|
Per Ib. |
Lbs. of Water Heated, 1°F. |
|||||
|
0 |
Air |
CO3 |
Per |
|||
|
Re- |
Viti- |
Pro- |
Per Ib. |
Cubic |
Per Ib. |
|
|
quired. |
ated. |
duced. |
Foot. |
O used. |
||
|
Cubic Feet. |
Cubic Feet. |
Cubic Feet. |
Lbs. |
Lbs. |
Lbs. |
|
|
Alcohol |
24-6 |
533 |
16-4 |
12,929 |
1.597 |
6,195 |
|
Camphine . . . |
38-9 |
880 |
27-8 |
19,573 |
7,134 |
5,942 |
|
Carbon |
31-0 |
943 |
31-5 |
14,544 |
|
5,447 |
|
Ether •. ' . |
30-9 |
664 |
20-4 |
16,249 |
3,217 |
6,158 |
|
Paraffin . . » |
40-5 |
878 |
27-0 |
21,327 |
— |
6,220 |
|
» oil . /';;,;.! |
40-5 |
878 |
27-0 |
21,327 |
— |
6.220 |
|
Rape oil r- r. . .-. |
38-7 |
801 |
24-3 |
17,752 |
— |
6,123 |
|
Sperm oil . . . |
38-7 |
801 |
24-3 |
17,230 |
|
6,088 |
|
Spermaceti! . |
37-0 |
815 |
25-2 |
17,589 |
|
6.088 |
|
Stearic acid . . . |
34-6 |
783 |
24-0 |
17,050 |
|
6,061 |
|
Stearine |
34-4 |
527 |
14-2 |
18,001 |
— |
6,143 |
|
Wax .... |
37-7 |
829 |
25-6 |
15,809 |
— |
4,995 |
332
GAS ENGINEER'S POCKET-BOOK.
Temperature of Combustion. (Letheby and Others.)
|
Open Flames. |
Closed Vessel. |
|||
|
InO. |
In Air. |
InO. |
In Air. |
|
|
Degrees. |
Degrees. |
Degrees. |
Degrees. |
|
|
H : .•':'., . , ... fcjjj |
14,510 |
5,744 |
19,036 |
7,852 |
|
Marsh gas . . . |
14.130 |
4,762 |
18,351 |
6,680 |
|
Olefiant gas . . |
16,535 |
5,217 |
21,344 |
7,200 |
|
Propylene . . »• . ?- |
16,522 |
5,239 |
21,327 |
7,177 |
|
Butylene -. ' . . .•;'' |
16,522 |
5,232 |
21,327 |
7,177 |
|
Acetylene . . . |
17,146 |
5,142 |
22,006 |
7,009 |
|
Benzole |
17,146 |
5,142 |
22,006 |
7,009 |
|
C02 .... |
12,719 |
5,358 |
16J73 |
7.225 |
|
cs, . . ; . . |
15,280 |
4.314 |
20,031 |
5,917 |
|
H2S .... |
13,688 |
4^388 |
17,542 |
6,026 |
|
Cyanogen . j 13,488 |
5.028 |
17,645 |
6,167 |
|
|
Coal gas (luminous) |
14,320 |
5^228 |
]8,101 |
7.001 |
|
Cannelgas . |
14,826 |
5,121 |
19,046 |
7,186 |
|
Wood spirit . . . |
11,435 |
4,641 |
14,902 |
6,347 |
|
Alcohol |
13,305 |
4,831 |
17,223 |
6,629 |
|
Ether . . .'_. '„,.- ' |
14,874 |
5.150 |
19,225 |
6,953 |
|
Camphine . . . r |
16,271 |
5^026 |
20.953 |
6,922 |
Expansion of Liquids, from 32° to 212° F. Volume at 32° = 1.
|
Liquid. |
Volume at 212° |
Expan- sion. |
Liquid. |
Volume at 212° |
Expan- sion. |
|
Alcohol . Nitric acid . Olive oil Turpentine . Air . |
1-1100 1-1100 1-0800 1-0700 1-374 |
| |
Sea water Water . . Mercury Spirits of wine |
1-0500 1-0466 1-018 1-110 |
i 1 |
To find the weight of water that can be evaporated from and at 212° F. in Ibs. per Ib. of fuel—
•15
or,
Total heat of combustion 966
Coefficient of the Expansion of Gases. (Charles's Law. )
All gases expand n^rd part of their volume for every degree Centi- grade increase in temperature above 0° ; or, in decimals, 0-003665.
FREEZING POINTS.
333
Expansion and Weight of Water from 32° to 500° F,
|
SLs £-2 1 |
Relative Volume by Expansion. |
Weight of 1 Cubic Foot. |
Weight of 1 Gallon. |
Tempera- 1 ture. |
Relative Volume by Expansion. |
Weight of 1 Cubic Foot. |
Weight of 1 Gal on. |
|
Deg. F. |
Lbs. |
Lbs. |
Deg.F. |
Lbs. |
Lbs- |
||
|
32 |
1-00000 |
62-418 |
10-0101 |
125 |
1-01239 |
61-654 |
9-887 |
|
35 |
•99993 |
62-422 |
10-0103 |
130 |
1-01390 |
61-563 |
9-873 |
|
39-1 |
•99989 |
62-425 |
10-0112 |
135 |
1-01539 |
61-472 |
9-859 |
|
40 |
•99989 |
62-425 |
10-0112 |
140 |
1-01690 |
61-381 |
9-844 |
|
45 |
•99993 |
62-422 |
10-0103 |
145 |
1-01839 |
61-291 |
9-829 |
|
46 |
1-00000 |
62-418 |
10-0101 |
150 |
1-01989 |
61-201 |
9-815 |
|
50 |
1-00015 |
62-409 |
10-0087 |
155 |
1-02164 |
61-096 |
9-799 |
|
52-3 |
1-00029 |
62-400 |
10-0072 |
160 |
1-02340 |
60-991 |
9-781 |
|
55 |
1-00038 |
62-394 |
10-0063 |
165 |
1-02589 |
60-843 |
9-757 |
|
60 |
1-00074 |
62-372 |
10-0053 |
170 |
1-02690 |
60-783 |
9-748 |
|
62 |
1-00101 |
62-355 |
10-0000 |
175 |
1-02906 |
60-665 |
9-728 |
|
65 |
1-00119 |
62-344 |
9-9982 |
180 |
1-03100 |
60-548 |
9-711 |
|
70 |
1-00160 |
62-313 |
9-9933 |
185 |
1-03300 |
60-430 |
9-691 |
|
75 |
1-00239 |
62-275 |
9-9871 |
190 |
1-03500 |
60-314 |
9-672 |
|
80 |
1-00299 |
62-232 |
9-980 |
195 |
1-03700 |
60-198 |
9-654 |
|
85 |
1-00379 |
62-182 |
9-972 |
200 |
1-03889 |
60-081 |
9-635 |
|
90 |
1-00459 |
62-133 |
9-964 |
205 |
.1-0414 |
59-93 |
9-611 |
|
95 |
1-00554 |
62-074 |
9-955 |
210 |
1-0434 |
59-82 |
9-594 |
|
100 |
1-00639 |
62-022 |
9-947 |
212 |
1-0466 |
59-64 |
9-565 |
|
105 |
1-00739 |
61-960 |
9-937 |
250 |
1-06243 |
58-75 |
9-422 |
|
110 |
1-00889 |
61-868 |
9-922 |
300 |
1-09563 |
56-97 |
9-136 |
|
115 |
1-00989 |
61-807 |
9-913 |
400 |
1-1 |
54-25 |
8-700 |
|
120 |
1-01139 |
61-715 |
9-897 |
500 |
1-2 |
51-16 |
8-204 |
Freezing Points.
Substances.
Bromine freezes at Oil anise „
„ olive
„ rose .,
Quicksilver „ Water
Centigrade. Fahrenheit.
. —20° =~40° 10° = 50° 10° = 50° 15° = 60°
, _39-4° =— 39° 0° = 32°
334
GAS ENGINEER'S POCKET-BOOK.
Melting Points and Expansions of Metals.
|
Metals. |
Specific Heat. |
Melting Point. |
Coefficient of Expansion. |
|
|
C. |
F. |
Per Degree F. |
||
|
Aluminium, pure |
•234 • |
704 to 899 |
1,300 to 1,650 |
j '00001235 |
|
Antimony . . . |
'0508 | |
432 to 621 |
810 to 1.150 |
} -00000601 |
|
Asphalt |
|
100 |
212 |
/ |
|
Bismuth . . . |
•031 |
264 |
507 |
•0000078 |
|
Brass .... |
•094 |
899 |
1,650 |
•00001047 |
|
Bronze . . . . |
|
921 |
1,690 |
|
|
Copper Gold, standard . . |
•0951 •095 |
1,091 1,180 |
1,996 2,156 |
•000001 •00000821 |
|
„ pure . |
— |
1,250 |
2,282 |
|
|
Iron, cast (grey) . . |
•130 |
1,124 |
2,056 |
•00000616 |
|
„ „ (white) |
•129 - |
1,050 to 1,100 |
1,922 to 2,012 |
|
|
„ wrought . . |
•110 |
1,600 |
2,912 |
•00000657 |
|
Lead . . . < v< |
•031 |
324 |
615 |
•00001555 |
|
Mercury . . . |
•033 |
39-4 |
-39 |
. -00009984 |
|
Nickel |
•109 |
1,543 |
2,810 |
•00000695 |
|
Platinum . . . |
•038 |
1,693 |
3,080 |
•00000493 |
|
Palladium . |
|
1,500 |
2,732 |
|
|
Silver . . . . |
•057 |
1,001 |
1,834 |
•00001063 |
|
Steel, hard . \ |
•117 |
f 1,300 |
2,732 |
•00000695 |
|
„ mild . . J |
± JL i |
1 1,400 |
2,552 |
•00000672 |
|
Tin . |
•057 |
230 |
444 |
•0000121 |
|
Zinc .... |
•096 |
401 |
754 |
•00001636 |
Melting Points of Solids.
|
Substance. |
Melting Points. |
Substance. |
Melting Points. |
||
|
C. |
F. |
C. |
F. |
||
|
Butter |
33-0 |
91 |
Sodium chloride |
776 |
1,429 |
|
Calcium chloride |
726 |
1.339 |
„ sulphate |
865 |
1,589 |
|
C02 . |
— |
—108 |
Spermaceti |
49 |
120 |
|
Ice . . . Iodine |
0 115 |
32 239 |
Stearine . . j |
43 to 49 |
109 to 120 |
|
Nitro-glycerine . |
7 |
45 |
Sulphur |
112 |
234 |
|
Phosphorus |
44 |
111 |
Tallow . . . |
33 |
92 |
|
Potassium iodate |
560 |
1.040 |
Turpentine |
—10 |
14 |
|
„ iodide |
634 |
1,173 |
Wax, bees' . . |
65 |
150 |
|
Silver nitrate . |
198 |
389 |
„ paraffin . |
45 |
114 |
BOILING POINTS.
335
Melting Points of Alloys.
|
Tin. |
Lead. |
Bismuth. |
Softens at. |
Melts at. |
|
Degrees F. |
Degrees F. |
|||
|
5 |
3 |
8 |
— |
202 |
|
1 |
1 |
1 |
— |
254 |
|
2 |
2 |
1 |
— |
292 |
|
4 |
4 |
1 |
|
320 |
|
2 |
1 |
. |
— |
340 |
|
4 |
1 |
_. |
|
365 |
|
1 |
1 |
— |
365 |
371 |
|
6 |
1 |
— |
— |
381 |
|
2 |
6 |
— |
372 |
383 |
|
2 |
7 |
|
377-5 |
388 |
|
2 |
8 |
._ |
395-5 |
408 |
|
1 |
2 |
— |
— |
441 |
|
1 |
3 |
— |
— |
482 |
|
1 |
5 |
— |
— |
511 |
Boiling Points, Latent Heat of Evaporation, and Heat from 32° F. of 1 Ib.
|
Boiling Point. |
Latent heat of Evapo- ration of 1 Ib. |
Volume at 32° F. = 1. Volume at 212° F. equals. |
Total heat from 32° F. of 1 Ib. |
||
|
C. |
F. |
||||
|
Alcohol .... |
78 |
173 |
374 |
1-110 |
461-7 |
|
Ammonia . ... |
60 |
140 |
|||
|
Benzine .... |
80 |
176 |
|||
|
Bisulphide of carbon . . |
47 |
116 |
|||
|
Bromine . . . • |
63 |
145 |
|||
|
Ether |
35 |
95 |
|||
|
„ nitrous . . , |
14 |
57 |
|||
|
Iodine |
181 |
347 |
|||
|
Linseed oil ... |
314 |
597 |
|||
|
Mercury . . . . |
342 |
648 |
|
1-018 |
|
|
Nitric acid |
— |
— |
|
1-110 |
|
|
Olive oil . . . . |
315 |
600 |
... |
1-080 |
|
|
Paraffin .... |
280 |
536 |
|||
|
Petroleum . . . . |
158 |
316 |
|||
|
Quicksilver |
350 |
662 |
|||
|
Salt ... |
413 |
775 |
|||
|
Sulphur .... |
236 |
447 |
|||
|
Sulphuric ether . . . |
38 |
100 |
175 |
___ |
210-4 |
|
Sulphurous acid |
—10 |
14 |
|||
|
157 |
315 |
124 |
1-070 |
256*6 |
|
|
Water .... |
100 |
212 |
965-2 |
1-047 |
1146*1 |
|
„ sea . |
101 |
213-2 |
— |
1-050 |
|
|
„ saturated brine |
108 |
226 |
|||
|
Wood spirit . . . . |
66 |
150 |
475 |
— |
545-9 |
|
Zinc |
1,040 |
1,904 |
— |
1-0029 |
336
GAS ENGINEER'S POCKET-BOOK.
The specific heat of a body is the ratio of the quantity of heat required to raise that body 1° in temperature, compared to the quantity of heat required to raise an equal weierht of water from 39° to 40° F.
Specific Heats.
|
Acid hydrochloric . |
. -600 |
Petroleum .: . I |
. '434 |
|
Alcohol . .; |
. -659 |
Phosphorus . . ^ |
. -2503 |
|
Benzene . |
. '3932 |
Quicklime . , T |
. -2169 |
|
Brickwork . |
. -192 |
Soda . . I . *% |
. -2311 |
|
Chalk |
. -2148 |
Stonework . |
. '197 |
|
Carbon |
. -2411 |
Sulphur |
. -2026 |
|
Charcoal . . .. . - |
. '2415 |
Sulphuric acid, density 1 |
•87 -3346 |
|
Coal, anthracite . - • « |
. -2017 |
„ 1-30 -6614 |
|
|
„ bituminous . |
. -2411 |
Sulphate of lead |
. -0872 |
|
Coke . . . ' . |
• -203* |
„ „ lime . ;. |
. -1966 |
|
Ether . . . |
. -521 |
Turpentine . . •'• |
. '416 |
|
Glass . .;.. .... .,., |
. -1937 |
Vinegar . . „ ™ . |
. -92 |
|
Graphite . ... |
. -2019 |
Water at 32° F. |
. ro |
|
Ice .... |
. -504 |
„ „ 212° F. . . |
. 1-013 |
|
Magnesium limestone |
. -2174 |
Wood, average |
. -550 |
|
Marble . . .^ |
. -2129 |
„ spirit |
. -6009 |
|
Olive oil . |
. -3096 |
* Increases as temperature rises.
The atomic specific heat of carbon is expressed by the following formulae :— From 0° to 250° C., it is C = 1-92 +0'0077£ ; from 250° to 1,000° C., it is C = 3-54 + 0-0246*. (MM. Uchene and Biju-Duval.)
Specific Heats of Gases, &c.
|
Equal Pressure. |
Equal Volume. |
Equal Pressure. |
Equal Volume. |
||
|
Acetone . . |
0-4125 |
0-8244 |
Hydrogen |
3-4046 |
0-2359 |
|
Air . |
0-2377 |
0-2374 |
H2S . |
0-2432 |
0-2857 |
|
Alcohol . |
0-4534 |
0-7171 |
Hydrochloric |
||
|
„ vapour |
0-4513 |
0-3200 |
acid |
0-1845 |
0-2333 |
|
Ammonia . . |
0-5083 |
0-2966 |
Light carburet- |
||
|
Benzole . |
0-3754 |
1-0114 |
ted hydrogen |
0-5929 |
0-4683 |
|
Binoxide of ni- |
Marsh gas . . |
0-5929 |
0-3277 |
||
|
trogen . . |
0-2315 |
0-2406 |
Nitrogen . |
0-2440 |
0-2370 |
|
Bromine . |
0-0555 |
0-3040 |
Nitric acid . . |
0-2317 |
0-2406 |
|
Chlorine . . |
0-1210 |
0-2962 |
„ oxide . |
0-2262 |
0-3447 |
|
CO . |
0-2479 |
0-2370 |
Oxygen . |
0-2182 |
0-2405 |
|
C02 . |
0-2164 |
0-3307 |
Steam,saturated |
— |
0-3050 |
|
CS2 . |
0-1570 |
0-4140 |
„ gas . . |
0-4750 |
0-2984 |
|
Chloroform . . |
0-1567 |
0-6461 |
Sulphurous an- |
||
|
Ether |
0-4810 |
1-2296 |
hydride |
0-1553 |
0-3414 |
|
Ethylene . . |
0-4040 |
0-4106 |
Turpentine. . |
0-4160 |
2-3776 |
FREEZING MIXTURES.
337
Specific Heat of Water at Different Temperatures,
|
Heat to Raise |
Heat to Raise |
||||
|
Tempera- ture, F. |
Specific Heat. |
1 Ib. Water from 32° F. to given Tempera- |
Tempera- ture, F. |
Specific Heat. |
1 Ib. Water from 32° F. to given Tempera- |
|
ture. |
ture. |
||||
|
Degrees. |
Units. |
Degrees. |
Units. |
||
|
32 |
I'OOOO |
o-ooo |
248 |
1-0177 |
217-449 |
|
50 |
1-0005 |
18-004 |
266 |
1-0204 |
235-791 |
|
68 |
1-0012 |
36-018 |
284 |
1-0232 |
254-187 |
|
86 |
1-0020 |
54-047 |
302 |
1-0262 |
272-628 |
|
104 |
1-0030 |
72-090 |
320 |
1-0294 |
291-132 |
|
122 |
1-0042 |
90-157 |
338 |
1-0328 |
309-690 |
|
140 |
1-0056 |
108-247 |
356 |
1-0364 |
328-320 |
|
158 |
1-0072 |
126-378 |
374 |
1-0401 |
347-004 |
|
176 |
1-0089 |
144-508 |
392 |
1-0440 |
365-760 |
|
194 |
1-0109 |
162-686 |
410 |
1-0481 |
384-588 |
|
212 |
1-0130 |
180-900 |
428 |
1-0524 |
403-488 |
|
230 |
1-0153 |
199-152 |
446 |
1-0568 |
422-478 |
Freezing Mixtures.
|
Fall in Temperature. |
Degrees Cold pro- duced. |
||
|
Nitrate of ammonia . Water . . |
1 part 1 v |
From + 50° to + 4° F. |
46° F. |
|
Dilute sulphuric acid . Snow . . . . |
2 „ 3 „ |
» + 32 „ - 23 „ |
55 „ |
|
Muriate of lime . Snow . . . . |
;} |
» +20 ,,-48,, |
68 ., |
|
Phosphate of soda |
9 , |
||
|
Nitrate of ammonia . |
6 ' |
„ + 50 „ - 21 ., |
71 „ |
|
Dilute nitric acid |
4 , j |
||
|
Common salt . . . Snow or powdered ice |
1 , } 2 1 |
From any temperature to - 5° F. |
|
|
Common salt Nitrate of ammonia . |
5 ' 5 > [ |
From any temperature |
|
|
Snow or powdered ice |
12 ; I |
to - 25° F. |
|
|
Sulphate of sodium . Dilute nitric acid . . |
3 , ) 2 , i |
From 10° C. to -- 18° C. |
|
|
Phosphate of sodium . Dilute nitric acid |
6 ' I 5 „ j |
on ?) 5) 5> ~ "V 5? |
|
|
Crystallized calcium |
|||
|
chloride . |
10 „ | |
» » -50 „ |
|
|
Snow . . . . |
7 j I |
Water (H20) when freezing expands from 1 volume to 1-09. G. E. Z
338
GAS ENGINEERS POCKET-BOOK.
Expansion of Liquids in Volume from 32° to 212°.
1,000 parts of water . . become 1,046
., ., oil . . . „ 1,080
., „ mercury . . „ 1,018
., ., spirits of wine ., 1,110
., ., atmospheric air „ 1,376
Latent Heat is the heat absorbed by any substance, without raising its temperature, in changing from the solid to the liquid state, or from the liquid to the gaseous state.
Latent Heats of Fusion,
Mercury Lead , Sulphur
5-4 9-4
Bismuth Silver . Water
12-6 21-1
80-2
Latent Heat Liquefaction.
Water at 39° F Bismuth Lead . Mercury
142-65
22-75
9-67
5-09
Silver
Tin
Zinc.
37-93 25-65 50-63
Comparative Powers of Solids for Conducting Heat.
Gold . . . 1,000
Platinum . . 981
Silver . . 973
Copper . . . 892
Brass . . 749
Iron, cast . . 562
„ wrought . 374
Zinc . . . 363
Aluminium Tin Lead . Marble . Bismuth . Porcelain Terra Gotta
305
304
180
24
18
12
11
Belative Heat Conductivity of Metals. Silver equals 1,000.
Silver
Gold .
Copper
Mercury
Aluminium
Zinc
"Wrought Iron
1,000 981 845 677 665 641 436
Tin . Steel . Platinum Cast Iron Lead . Antimony Bismuth
422 397 380 359 287 215 61
RADIATION OF HEAT,
339
Comparative Powers of Solids for Absorbing or Eadiating and Reflecting.
|
Reflecting. |
Absorbing. |
|
|
Silver, polished . |
97 per cent. |
3 per cent. |
|
Gold .... |
95 „ „ |
" ?> »> |
|
Copper |
93 „ „ |
7 „ , |
|
Brass, bright polished |
93 „ „ |
7 „ , |
|
„ dead „ |
89 ., „ |
11 „ , |
|
Speculum metal . . |
86 , „ |
14 „ > |
|
Tin .... |
85 , „ |
15 „ , |
|
Steel, polished . . |
83 , „ |
17 „ , |
|
Platinum, sheet . |
83 , „ |
17 „ , |
|
., polished |
80 , „ |
20 „ , |
|
Zinc .... |
81 , „ |
19 „ , |
|
Mercury . . . |
77 „ „ |
23 „ , |
|
Iron, wrought, polished |
77 „ „ |
23 „ , |
|
„ cast, „ . |
75 „ „ |
25 „ , |
|
Silver leaf on glass |
73 „ , |
27 ., , |
|
Ice |
IB „ , |
85 „ , |
|
Glass .... |
10 „ , |
90 „ , |
|
Writing paper . . |
2 „ , |
98 „ , |
|
Water. |
o „ , |
100 „ , |
|
Marble .... |
2 to 7 „ , |
98 to 93 „ , |
Quantity of Heat Lost per Square Unit of Surface. (Peclet.)
Excess of Temperature
of Gas over Air. 10° . 20° 30° . 40° . 50° .
Loss in Air.
. 8 .
. 18
, 29 .
, 40
, 53 .
Loss in Water.
88
266
5,353
8.944
13^437
Effect of Mixing Water at Different Temperatures.
1 Ib. of water at 0° C. + 1 Ib. of water at 10° C. equals 2 Ibs. of water at 8° C.
1 Ib. of water at 0° C. + 1 Ib. of water at 35° C. equals 2 Ibs. of water at 17-5° C.
1 Ib. of water at 16° C. + 1 Ib. of water at 35° C. equals 2 Ibs. of water at 25-5° C.
1 Ib. of water cooling from 16° to 8° raised the temperature of 1 Ib. from 0° to 8°.
Convection is the transference of heat by particles. Conduction is the transmission from particle to particle.
Z2
340
GAS ENGINEER'S POCKET-BOOK.
Board of Trade Thermal Unit equals quantity of heat necessary to raise 1 Ib. pure water 1°F. from 39-1° to 40-1°.
Calorie equals quantity of heat necessary to raise 1 kilogramme pure water 1° C. at or about 4° C,
B. T. U. X '252 = Calories, or Calories X 3-968 = B. T. U.
Joule's Law — 1 B. T. U. equals 772 foot Ibs. work performed.
Joule's law shows that the quantity of work required to raise the temperature of 1 Ib. of water, weighed in vacuum, from 60° to 61° F. equals 772*55 foot Ibs. at sea level in the latitude of Greenwich ; or the amount of work that is converted into heat by raising 1 Ib. of water 1° C. is 1,390 foot Ibs. (fths of 772).
Metals all possess the same atomic heat = 6-4.
To convert Fahrenheit to Centigrade
9 C "
To convert Centigrade to Fahrenheit — =-" -j- 32 = F.
Comparison of the Value of Coal Gas for Motive Power and Lighting at Different Candle Powers. (C. Hunt.)
|
Illuminating Power of Gas. Candles. |
Consumption per I.H.P. per Hour. Cubic Feet. |
Value for Motive Power. |
Value for Lighting. |
|
11-96 |
30-31 |
1-000 |
i-ooo |
|
15-00 |
24-41 |
1-241 |
1-254 |
|
17-20 |
22-70 |
1-335 |
1-438 |
|
22-85 |
17-73 |
1-709 |
1-910 |
|
26-00 |
16-26 |
1-864 |
2-173 |
|
29-14 |
15-00 |
2-020 |
2-436 |
Calorific Value of Coal Gas. (T. L. Millar.)
|
Illuminating Power. |
Heating Power per Cubic Feet. |
|
|
Glasgow . Liverpool . . . Kilmarnock Manchester . . . Birmingham London . . . Hoboken Berlin . . . |
21^ candles 21 25 16 and 19J candles 17£ candles 16 |
813 heat units 770 , 680 . „ 654 , 639 . 624 , 617 , 549 , |
Theoretical value in heat units of 1 cubic foot of gas equals 660 to 670 (1 Ib. water heated 1° F.).
HEAT UNITS FROM DIFFERENT SUBSTANCES. 341
The number of heat units obtainable in practice is : — In the best bath heaters, about 600 ; in the best boiling burners, about 375.
Effective heating duty of coal gas in small vessels equals 300 to 320 units.
Effective heating duty of coal gas in ordinary flat-bottomed vessels with projecting rivets equals 520 units.
Effective heating duty of coal gas in domestic pans and kettles equals 300 units.
Effective heating duty of coal gas in small pans and kettles equals 3 50 units. (T.Fletcher.)
15 candle gas gives 020 heat units per cubic foot. 19 „ „ 800
28 „ „ 950
(N. H. Humphreys.)
1 Ib. H burning to H20 gives off 62,535 heat units. 1 Ib. C „ C0.2 ., 12,906 1 Ib. C „ CO „ 2,495
1 Ib. CO ., C02 „ 4,478
(Dulong.)
Carbon, when combined with hydrogen to form defiant gas (C2H4) and acetylene (C2H2), has a lockcd-up heat energy, as compared with the carbon forming marsh gas (CH4) of 31,300 and 75,430 heat units respectively which are developed as light and heat when the gases are burned. (W. Young.)
Heat Units Generated by Complete Combustion per Ib.
Hydrogen 62,000 heat units.
Carbon 14,500 „
Sulphur 4,000
The maximum temperature obtainable by the combustion of 0 equals about 5,000° F.
The maximum temperature obtainable by the combustion of H equals about 5,800° F.
Heat Units per Ib. Favre and Silbermann.
H . . . ' . . . . 34,462
C 7,770
Coke (dessicated) .... 7,000 CO 2,400
Heat unit equals 1 kilo, water raised 1° C.
Calorific value of H = 34,500 units.
„ „ Methane = 8,080 „
Sulphur evolves 2,220 units of heat per Ib.
Average coke yields 12,000 heat units per Ib. when burnt to C02.
Pure carbon yields 14,500 heat units per Ib. when burnt to C02.
342 GAS ENGINEER'S POCKET-BOOK.
For every Ib. H combined with 0 to form water, sufficient heat is evolved to raise 34,400 Ibs. water 1° C.
One ton coal . . . . = 8,353,846-640 calories. 10,000 cubic feet gas . . = 1,635,000*000 •»
An average Lancashire coal is said to have a calorific power of 13,890, which means that 1 Ib. of the coal would raise 13,890 Ibs. water through 1° F. of temperature.
Kelative calorific intensity of coke per Ib. = 2,114° C. „ 'tar „ = 2,486° C.
(F. G. Dexter.)
1 Ib. H + 8 Ibs. 0 will raise 34,4621bs. water 1° C.
Latent heat of steam . . . 536 thermal units
„ water . . . . 79 „ „
Maximum heat obtainable by air blast . . 2,500°
The boiling point of hydrogen is found to be 234-5° below zero. Benzene or benzol (C6H6) boils at 81° and freezes at 0° 0. Napthalene (C10H8) melts at 80° and boils at 217° C. Anthracene (C14Hi0) melts at 213° and boils at a little above 360° C.
To prepare Acetate of Lead Test Papers.
Moisten sheets of bibulous paper with a solution of 1 part sugar of lead in 8 or 9 parts water and hold each sheet, while still damp, over the surface of a strong solution of ammonia for a few moments.
Such papers will become tinged if subjected to gas containing 0-001 per cent, by volume of H2S for 24 hours, light being excluded during that time.
To make Turmeric Papers.
Six parts methylated spirit to 1 of turmeric powder by weight, to be well shaken from time to time for 3 days. Decant clear liquid and soak sheets of botanical or filtering paper in it, dry and keep in the dark. The papers should be a full yellow colour. *0ne grain or more NH3 per 100 cubic feet will cause the colour to change to brownish tint.
To make Bed Litmus Paper.
Dissolve 1 oz. powdered blue litmus in 6 ozs. cold distilled water and shake well, allow to dissolve and filter, add gradually dilute HaS04 until it is changed to a red tint ; soak sheets of glazed paper in it and dry. These papers turn blue when exposed to gas contain- ing NH3.
To make Lime Water.
Dissolve 4 ozs. caustic lime in 1 quart water, shake occasionally, decant the clear liquid and keep it free from G0.2.
If gas containing C02 is bubbled through a portion of above, it forms CaC03, the liquid becoming milky, thus :
CaO + C0a = CaC03.
TO PREPARE INDICATORS. 343
If still clear, after bubbling for 3 minutes, the gas is probably quite free from C02.
All H2S must be removed from the gas by means of oxide of iron before making above test.
To prepare Litmus for Indicating Acids and Alkalies.
Digest solid litmus in hot water and evaporate to a certain degree, add a small quantity acetic acid. Evaporate again and add methy- lated spirit. Filter the precipitate and wash with spirit, dissolve with warm water and add a small quantity nitric acid. Keep exposed to the air to preserve the colour. Free C02 effects the change in colour of the solution.
To prepare Cochineal for Analysis of Ammonia.
Take 1 part methylated spirit and 4 parts water, keep at a gentle heat for some hours with about 10 grammes cochineal powder to every 1,000 cubic centimetres of the solution, cool and decant the clear liquid. Its yellow colour is changed to red by alkalies, and to yellow again by mineral acids and is not affected by C02.
The acid must be added to the alkali solution when using this indicator.
To prepare Methyl-orange for estimating Ammonia in Gas.
Dissolve 1 gramme of methyl-orange, in powder, in methylated spirit and make up to 1 litre with a solution of one part water and one part methylated spirit.
The colour is changed to yellow by alkalies and then to red by acids ; it is not affected by C02.
To prepare Phenol-phthalein.
Make an alcoholic solution which should be colourless, but an alkali causes it to become red, and this is again destroyed by an acid. Phenol-phthalein is affected by the presence of ammonia salts or C02.
Standard Solution.
For testing gas liquor (Will's test) —
125 cubic centimetres NH3 (specific gravity '880) to 1 litre H20.
10 per cent, acid (specific gravity of strong acid).
/I -067 = 9-8 per cent. acid.
\10 parts to 90 of water.
10 per cent, acid = 1064-4 specific gravity.
To prepare Standard Acid Solution for test of Ammonia.
Measure a gallon of distilled water in a clean earthenware jar or other suitable vessel. Add to this 94 septems of pure concentrated sulphuric acid and mix thoroughly. Take exactly 50 septems of the liquid and precipitate it with barium chloride in the manner prescribed for the sulphur test. The weight of barium sulphate which 50
344 GAS ENGINEER'S POCKET-BOOK.
septems of the test acid should yield is 13'8 grains. The weight obtained with the dilute acid prepared as above will be somewhat greater, unless the sulphuric acid used had a specific gravity below rS4. Add now to the dilute acid a measured quantity of water, which is to be found by subtracting 13*8 from the weight of barium sulphate obtained in the experiment and multiplying the difference by 720. The resulting number is the number of septems of water to be added. If these operations have been accurately performed, a second precipitation and weighing of the barium sulphate obtainable from 50 septems of the test acid will give nearly the correct number of 13-8 grains. If the weight exceeds 13*9 grains, or falls below 13-7 grains more water or sulphuric acid must be added, and fresh trials made until the weight falls within these limits. The test-acid thus prepared should be transferred at once to stoppered bottles which have been well drained, and are duly labelled. (Metropolitan Gas Referees.)
To prepare the Standard Solution of Ammonia.
Measure out as before a gallon of distilled water, and mix with it 20 septems of strong solution ammonia (specific gravity O'SS). Try whether 100 septems of the test alkali thus prepared will neutralize 25 of the test acid, proceeding according to the -direction given sub- sequently as to the mode of testing. If the acid is just neutralized by the last few drops, the test-alkali is of the required strength ; but if not, small additional quantities of water or of strong ammonia solution must be added, and fresh trials made, until the proper strength has been attained. The bottles in which the solution is stored should be filled nearly full and well stoppered. (Metropolitan Gas Keferees.)
To prepare Potassium Hydroxide for determining C02.
Use commercial stick potash, not purified by alcohol, dissolve 8 ozs. in a pint of distilled water for careful and exact tests, but for ordinary work, a more dilute solution may be used.
To prepare Bromine for determining the Hydrocarbons.
Make an aqueous solution of bromine almost saturated. Before measuring the absorption the vapour of the bromine must be removed by potassium hydroxide solution.
A solution of bromine in potassium bromide is sometimes used.
To prepare Cuprous Chloride Solution for determining CO.
For the hydrochloric acid solution, place 100 grammes of precipi- tated cuprous chloride in a bottle and pour on 500 cubic centimetres of concentrated hydrochloric acid, into which put some copper spirals so as to reach to the top of the liquid.
For the ammoniacal solution, place 40 grammes of precipitated cuprous chloride in a bottle and fill up with 400 cubic centimetres of water, into this bubble some ammonia gas, made by boiling some
TO PREPARE NORMAL SOLUTIONS. 345
strong ammonia solution, the fumes from which are carried into the bottle containing the cuprous chloride, until the latter assumes a pale blue colour, then make the solution up to 500 cubic centimetres, and carefully stopper the bottle.
To prepare Sulphuric Acid for determining the Hydrocarbons,
The acid to be used must be strongly fuming acid (Nordhausen) which on cooling to a slight degree below usual temperatures, deposits crystals readily. It is used either on coke balls thoroughly saturated or in absorption pipettes with glass balls inside. Before measuring the absorption, the acid vapours must be removed by potassium hydroxide solution.
To prepare Pyrogallie Acid Solution for determining Oxygen.
Dissolve fresh pyrogallic acid in 3 times its weight of water (distilled). After pouring this into the absorption tube, put in eight times the volume of caustic potash solution. The absorption of oxygen is slow and requires about 5 minutes' agitation.
To prepare Normal Oxalic Acid.
This solution should contain 03 grammes per litre. Dissolve this quantity in distilled water and make up to 1 litre. Test against normal alkali. Do not use this acid with methyl-orange, and keep it out of direct sunlight.
To prepare Normal Hydrochloric Acid,
This solution should contain 36 -5 grammes per litre. Dilute strong hydrochloric acid with distilled water and make it of MO specific gravity at 60° F. Test against normal solution of sodium hydrate and dilute to normal strength.
To prepare Normal Sulphuric Acid Solution.
This should contain 49 grammes pure H2SO4 per litre. Add strong sulphuric acid to distilled water, and when cool test by means of standard sodium carbonate solution, and add water to reduce to normal strength. When the solution is correct an equal quantity of the acid should exactly neutralize an equal quantity of the alkali.
To prepare Normal Solution of Sodium Carbonate.
The solution should contain 53 grammes pure Na3C03 per litre and the Na2C03 should be dissolved in the water, and, when at normal temperature, the amount made up to the exact quantity by adding distilled water.
To prepare Normal Sodium Hydrate Solution.
This solution should contain 40 grammes per litre. Dissolve about 44 grammes caustic soda, purified by alcohol, in distilled water, recently boiled and cooled,
346
GAS ENGINEER'S POCKET-BOOK.
Or use 25 grammes clean metallic sodium in distilled water. Test with normal acid solution and dilute to proper strength. Specific gravity of solution 50 grammes per litre equals 1*05.
25 septems standard acid neutralize 1 grain NH3. 100 „ „ ammonia contain 1 grain NH3.
Equivalent Normal Solutions.
Nitric acid 63 grams per litre.
Anhydrous carbonate of soda
Sulphuric acid Sodic hydrate . Hydrochloric acid . Ammonia .
53
49
40
36-5
17
Degrees of Twaddell's Hydrometer compared with Specific Gravity.
|
Twaddell. |
Specific Gravity. |
Twaddell. |
Specific Gravity. |
Twaddell. |
Specific Gravity. |
Twaddell. |
Specific Gravity. |
|
0 |
1-000 |
6 |
1-030 |
13 |
1-065 |
19 |
1-095 |
|
1 |
1-005 |
7 |
1-035 |
13-4 |
1-067 |
20 |
•100 |
|
1-4 |
1-007 |
7-4 |
1-037 |
14 |
1-070 |
21 |
•105 |
|
2 |
1-010 |
8 |
1-040 |
15 |
1-075 |
21-6 |
•108 |
|
2-8 |
1-014 |
9 |
1-045 |
16 |
1-080 |
22 |
•110 |
|
3 |
1-015 |
10 |
1-050 |
16-6 |
1-083 |
23 |
•115 |
|
4 |
1-020 |
10-2 |
1-052 |
17-0 |
1-085 |
23-2 |
•116 |
|
4-4 |
1-022 |
11 |
1-055 |
18-0 |
1-090 |
24 |
•120 |
|
5 |
1-025 |
12 |
1-060 |
18-2 |
1-091 |
25 |
•125 |
|
5-8 |
1-029 |
Degrees Twaddell x 5 -f- I'OOO equals specific gravity.
Specific gravity -1-000
— ^— g — = Degrees Twaddell.
To find the volume of air required to chemically combine with any fuel to support complete combustion : —
1-52 { per cent, of C+3 (per cent, of H)— -4 (per cent, of 0) }
equals cubic feet per Ib. fuel, of air as at 62° F. and at one atmosphere.
In above no notice is taken of the air required by the sulphur, which is only nominal.
To find the volume of gaseous products on complete combustion of 1 Ib. fuel as at 62° F. at one atmosphere.
(1-52 X per cent, of C) + (5-52 X per cent, of H)
To find the weight of gaseous products on complete combustion of 1 Ib. fuel as at 62° F. at one atmosphere : —
(-126 X per cent, of C) + (-358 X per cent, of H)
LOSS OF LIGHT ON MIXING AIR WITH GAS.
347
To find the total heat of combustion of any fuel containing G and H :—
145 | per cent, of C + (4-28 X per cent, H) j-
The richer the gas the greater the quantity of 0 required for complete combustion.
1 volume gas requires 5J volumes air for complete combustion.
Results of different mixtures of Gas and Air on Light given by Incandescent Burners. (W. Foulis.)
Illuminating Power Glasgow Gas. Air. per CubicbFoot.
1 . . . 7 . . . . 13-0 candles.
1 . 5-8 ... 28-2 „
1 . . . . 4 . . . . 17-3 „ With gases of over 50 candle power the addition of small quantities of 0 increases the illuminating power by combining rapidly with the H of the hydrocarbons and therefore not requiring the use of a similar quantity of 0 combined with N from the air, the N acting merely as a diluent, with low quality gases the quantity of 0 possible to effect an increase is very minute.
The addition of a small proportion of oxygen to coal gas was found by Dr. P. Frankland to sensibly increase the illuminating power, but the addition of even a small quantity of nitrogen materially decreases it. 1 per cent. N reduced the luminosity 1 per cent.
Loss of Light by the addition of air to Coal Gas. (Wurtz.)
Air.
3-00
4-96
11-71
16-18 25-00
Loss of Light. 15-69 per cent, 23*83 „ ,, 41-46 „ „ 57-53 „ „ 84-00 ,
Loss of Light per Cent, by Mixing Air with Coal Gas.
|
Air, per cent . |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
15 |
20 |
30 |
40 |
|
Loss of Light, |
||||||||||||||
|
per cent. . |
6 |
11 |
18 |
26 |
33 |
44 |
53 |
58 |
64 |
67 |
80 |
93 |
98 |
100 |
The reason C02 is a more harmful substance than N is that the specific heat of C02 is nearly half as much again as that of N and consequently the amount of heat taken up by C02 in being raised to the temperature of the flame is greater than that taken up by nitrogen.
One per cent. C02 reduces the illuminating power about 4 per cent.
C02, air, N, and water vapour, cool and dilute flames.
H and CO dilute only.
The addition of N to pure ethylene reduces luminosity in propor- tion to its volume, but probably when N is added to coal gas some of the tarry vapours are carried forward by it, and the luminosity is therefore not decreased to the same extent.
348
GAS ENGINEER'S POCKET-BOOK.
Comparative Duty of Different Burners with 16-candle Gas. (Professor Lewes.)
Light per Cubic Foot
of Gas. . . 2-15
. 2-44 . . 2-90
. 3-20 . . 10-00
Efficiency of Incandescent Burners with Different Quality Gases, (Foulis.)
|
Burner. Flat flame, No. 0 . j> ?> » 1 o j> ?> »> ^ • » ,, „ 3 » >? 5» * • ?> >» »» ° |
Light per Cubic Foot of Gas. . . 0-59 . 0-85 . . 1-22 . ., . 1-63 . . 1-74 . '• : ; 1-87 |
Burner. Flat flame, No. 6 . Ordinary Argaud Standard „ Regenerative |
|
Ordinary Burner (Flat Flame). |
Incandescent Burner. |
||
|
Illuminating Power Corrected to 5 Cubic Feet |
Candles per Cubic Foot. |
Illuminating Power Coirected to 5 Cubic Feet. |
Candles per Cubic Foot. |
|
28-1 17-9 10-2 14-6 . 13-5 |
4-6 3-6 3-2 2-9 2-7 |
117-3 90-3 87-9 84-4 81-9 |
23-40 18-07 17-59 10-89 16-39 |
The following Table gives the results obtained with Edinburgh gas when consumed from various burners : — Five cubic feet are equal to : —
Candle Power.
. 25-00
8 . . . . 29-43 3 .... 21-72 * .... 26-66 § . * . . 28-37 g . . . . 30-39
: 36-16
36-76 36-87 28-00 32-35 18-12 20-75 25-00
;,' g ... 23-75
„ | . . . 28-57
„ Street Burner . . . 19-41
Welsbach " S " Burner .... 53-30
„ "C" „ . . . . 61-95
(Professor W. I. Macadam.) With a Union jet CH4 and C2H0 are non-luminous.
Bray No. 8 . Bray " Special " No Bray Adjustable
Milne's Old Regulator . . . Spon's Deflector and No. 7 Bray Noleton Duplex (No. 0 Bray) Parkinson Regulator and No. 7. Bray Peeble's Regulator, No. |
COMPOSITION OF COAL GAS.
349
Average Composition of London Gas. (Dr. Letheby.)
|
Common Gas. |
Cannel Gas. |
|
|
Twelve |
Twenty |
|
|
Candle. |
Candle. |
|
|
Hydrogen |
4<>'0 |
27-7 |
|
Light carburetted hydrogen . . . |
39-5 |
50-0 |
|
Condensable hj^drocarbons . |
3-8 |
13-0 |
|
Carbonic acid |
0-6 |
o-i |
|
Carbonic oxide |
7-5 |
6-8 |
|
Aqueous vapour |
2-0 |
2-0 |
|
Oxygen |
O'l |
0.0 |
|
Nitrogen |
0-5 |
0-4 |
|
100-0 |
100-0 |
Analysis of London Gas at probably 12 Candle Power, (Thwaite.)
Unsaturated hydrocarbons Benzol .... Marsh Gas
Carbon anhydride . CO ....
H
O
N
Pel- Cent. 3-84 1-04
35-63 1-41 6-15
47-73 0-30 3-90
Analysis of Coal Gas, London. (Latwct.')
Benzene (CaH6) . Olefines (C2H4) Carbon monoxide (CO) Hydrogen (H) . Methane (CHJ Nitrogen (N) .
By Volume.
0-55 . 4-45 . 7-80 . 52-90 . 31-80
2-50
By Weight.
3-98 11-70 20-00
9-84 48-00
6-42
Average Composition of 16 to 17 Candles Caking Coal Gas.
(L. T. Wright.)
Per Cent. Hydrocarbons capable of absorption, say
(CnHm) ...... 4
Paraffins, treated as Marsh gas (CH4) . . 38
CO 6
H 48 to 50
N 2
350
GAS ENGINEER'S POCKET-BOOK.
Composition of London Gas, 26th May, 1893.
(Professor Lewes.)
|
SouthMetropolitan Gas Company. |
Gas Light and Coke Company. |
|
|
Hydrogen Unsaturated hydrocarbons . Saturated hydrocarbons . CO. ... |
50-16 3-50 36-25 5-68 |
53-36 3-58 32-69 7-05 |
|
N . C00 . |
4-10 o-oo |
2-50 0-61 |
|
o - . . |
0-31 |
0-21 |
|
H2S |
nil |
nil |
|
100-00 |
100-00 |
Composition of London Gas Companies' Coal Gas. (Professor Lewes.)
|
South Metropolitan. |
Gas Light and Coke. |
Commercial. |
|
|
Hydrogen ... ,| Unsaturated hydrocarbons . . Saturated hydrocarbons . CO C02 . |
52-22 3-47 34-76 4-23 0-60 |
53-36 3-58 32-69 7-05 0-61 |
52-96 3-24 34-20 4-75 0-75 |
|
N • O |
4-23 0-49 |
2-50 0-21 |
5-10 o-oo |
Unsaturated hydro- carbons, C3H4 .
Saturated hydro- carbons, CaH6 .
Saturated hydro- carbons. CH4
CO . ' .
N .
Approximate Analysis of London Coal Gas.
(Professor V. B. Lewes.) by volume 52'0 per cent., by weight 9'6 per cent
3-0 1-0
34-0 5-0 4-5 0-0
0-5
7-7 7-1
49*9
12-8
11-5
0-0
1-4
The illuminating power is far more dependent upon the mode in which the C is combined than upon the actual percentage present in the gas. (W. Young.)
COMPOSITION OF ILLUMINATING GASES.
351
Composition of Coal Gas by Volume.
H . . . 34 to 53 per cent. CH4 marsh gas 43 to 36 CO , . 6 to 2-7
0 and C00 . 1 to O3 percent, C4He defines 13 to 3'0 ., N . 3 to 5-0 „
Composition in 100 Volumes. (Sir H. Koscoe.)
|
Illuminating |
N |
||||||
|
Power in Candles per 5 |
H. |
CHt. |
CnH3n. |
C,H4. |
CO. |
0 |
|
|
Cubic Feet. |
CO2. |
||||||
|
Cannel gas |
34-4 |
25-82 |
51-20 |
13-06 |
(22-08) |
7-85 |
2-07 |
|
Coal gas . |
13-0 |
47-60 |
41-53 |
3-05 |
( 6-97) |
7-82 |
Average Composition of Natural Gas in America.
H = 22 per cent.
Marsh gas = 67 „
Other bodies in small quantities^ 11 „
100
Composition of Coal Gas, Water Gas, and a Mixture. (E. G. Love, 1889.)
|
Coal. |
Water. |
Mixture. |
|
|
Hydrogen .... Marsh gas CO . . |
39-78 45-16 7-04 |
29-16 24-42 28-33 |
34-47 34-79 17-685 |
|
Ethylene Ethane Benzol vapour CO2 .... 0 N ...... |
4-34 2-04 1-08 0-06 0-50 |
12-46 0-78 2-88 0-21 1-76 |
8-40 0-39 2-46 0-54 0-135 1-13 |
|
Specific gravity (calculated) . Calorific power, heat units Air required for combustion of 1 Ib. of gas, Ibs. . |
100-00 0-4644 19233-6 14-70 |
100-00 0-6551 13913-6 10-22 |
100-00 0-5597 16114-4 13-08 |
(Extract from paper by E. G. Love, at Baltimore, U.S.A., 1889.)
352
GAS ENGINEER'S POCKET-BOOK.
Comparative Analysis of Coal Gas and Carburetted Water Gas. (A. E. Broadberry.)
|
Description of Gas. |
H.S. |
C02. |
Illuini- nants. |
0. |
CO. |
H. |
Marsh Gas. |
*Bal- ance. |
|
Unpurified car- |
||||||||
|
buretted water |
||||||||
|
gas . Unpurified coal |
0-4 |
6-0 |
8-8 |
0-5 |
27-4 |
32-3 |
20-5 |
4-1 |
|
gas from scrub- |
||||||||
|
ber outlet |
1*4 |
1-3 |
2-3 |
1-1 |
5-2 |
43-0 |
37-1 |
8-0 |
|
Combined gas, |
||||||||
|
purified equals |
||||||||
|
35 per cent.car- |
||||||||
|
buretted water |
||||||||
|
gas |
— |
— |
4-8 |
0-2 |
13-8 |
41-1 |
32-7 |
7-4 |
* Probably N.
Specific gravity of combined gases, *5, H2S and C02, calculated by explosion and absorption.
Napthalene is a white, shining, crystalline substance, fusing at 176° F., and boiling at 423° F., but volatilizing when brought into contact with steam. It is not soluble in water, but readily dissolves in alcohol, chloroform, naptha, ether, or carbon disulphide. When napthaleiie is found, the condition of the coal should first be looked after. The use of wet coal, particularly if slack, should be avoided.
A test is to neutralise the liquor with dilute sulphuric acid. If napthalene be present, the liquor assumes a rose colour, and the sulphate solution gives off the peculiar odour distinctly characteristic of napthalene.
Carbon Monoxide (CO) is colourless, and has no taste, burns with a lambent blue flame on admixture with oxygen and forms C02.
Can be absorbed by a solution of cuprous chloride (Cu2 C12).
Carbonic oxide is a colourless gas which burns with a bright blue flame forming C02, 2 or 3 per cent, in the air may prove fatal, it has no odour. Specific gravity is '968, 100 cubic inches, weighs 30 grains.
Carbon Dioxide (C02) is colourless and has no smell, and is formed whenever carbon is burnt in excess of air or oxygen.
Ethylene or Olefiant Gas (C2 H4) is colourless and of a sweet taste, burns with a smoky luminous flame in air, explodes loudly when mixed with 3 volumes 0 and fired, the same quantity being required to cause complete combustion.
Methane or Marsh. Gas (CH4) is colourless, and burns with a non- luminous flame, is tasteless, and has no odour ; 1 volume CH4 and 3 volumes 0 explode with a light when 1 volume 0 remains.
Marsh gas weighs 17'41 grains per 100 cubic inches. Density is '559.
VALUES OF ILLUMINATING GASES. 353
Relative, Calculated, and Found Values of Gases, (Professor V. B. Lewes.)
Illuminating Value. Calculated. Found.
Methane . 8-4 5-2
Ethane . . 35-0 . . . 35-0
Ethylene . . . 60-9 . . 68'5
Acetylene .... 202-2 . . . 240'0
At between 1,500° and 1,600° F., ethylene is broken up into acetylene and methane, with formation of benzene ; and at 1,832° F. napthalene and other bodies are formed, and at 2,000° F. are again broken down to acetylene, which then decomposes into C and H. (Professor V. B. Lewes.)
Not more than 2 cubic feet per hour of ethylene or ethane can be used in a " London " Argand burner without smoking.
The boiling point of ethane is 89'5 at 735 millimetres pressure.
The density of liquid ethane was found to be 0-446 at 0° and 0-396 at + 10-5°. (Dewar.)
Illuminating value of ethane 35, ethylene 68, acetylene 240.
Propane is a perfectly colourless liquid, but much more viscous than liquid carbon dioxide.
Heptane was found practically insoluble in water.
Boiling point of phenanthrene equals 350° C.
Olefiant gas bums well, 100 cubic inches weigh 30-57 grains. Density is '981.
Acetylene is colourless and burns with a very brilliant flame. Specific gravity is -920. If chlorine is added to acetylene the mixture explodes.
Specific gravity of CS2 equals 1*29.
CSa boils at 46° C.
CS2 vapour ignites at 300° F. (149° C.) when ethylene is not present.
Benzene C6H6. Toluene C7H8. Xylene C8H10.
Napthalene C10H8. Heptane C7H16.
Propane is obtained in a state of purity by heating propyliodide with aluminium chloride in a sealed tube to 130°. After subjection to this temperature for twenty hours the tube is allowed to cool and subsequently placed in a freezing mixture. (A. E. Tutton.)
Lithium hydride is formed by raising metallic lithium to a red heat in an atmosphere of hydrogen. The gas is absorbed by the metal forming a white powder on which the atmosphere acts only very feebly. When wetted the powder restores the hydrogen it has absorbed and the quantity given off is greater weight for weight than is obtainable from any other material.
Argon density equals 19-940 to 19-941.
Argon viscosity equals 121. Air equals 100.
Specific gravity of graphite equals 2-15 to 2'35.
G.E. A A
354
GAS ENGINEER'S POCKET-BOOK.
Specific gravity of hydrogen gas equals -069.
A column of any perfect gas expands from 1 to 1*3665 between 0° C. and 100° C.
One cubic foot hydrogen weighs 37 grains, therefore to obtain weight of 1 cubic foot in gas of any gas, multiply half molecular weight if a compound gas, or molecular weight if a simple gas X 37.
The atomic weight of an elementary gas X '0691 equals its specific gravity.
Half the atomic weight of a compound gas or vapour X '0691 equals its specific gravity.
One litre H gas at 0° C., and 760 millimetres pressure, weighs 0-0896 grains.
H liquefies at about - 200° C.
Specific gravity 0 equals 1-1056, liquefies at - 14° C., and a pressure of 320 atmospheres.
To obtain weight in grains of any gas : specific gravity X 537 (weight of 1 cubic foot air) = grains per cubic foot.
The correct temperature of the boiling point of propane is found to be - 37° at 760 millimetres pressure. (Tutton.)
Ammonia density, -589 ; weight of 100 cubic inches is 18-26 grains.
The hydrocarbons in unenriched coal gas, which give it its luminosity, are principally methane, ethylene, and benzene vapour.
Usually accepted theory of light is, tbat there are three distinct zones ; the inner zone consisting of unburned gas. the middle lumin- ous zone, where the H changes into water, developing heat, and consequent incandescence of C, and the outer zone, where the C becomes carbon anhydride.
Flame Temperatures. (Professor V. B. Lewes.)
Inner zone temperature rises from a comparatively low point at the mouth of the burner, to between 1,000° and 1,100° at the apex of the zone. Here takes place the conversion of the hydrocarbons into acetylene : the luminous zone, in which the temperature ranges from 1,100° to a little over 1,300°, with a decomposition of the elements of the acetylene formed in the inner zone ; the extreme outer zone, in which the cooling and diluting influence of the entering air renders a thin layer non-luminous, and finally extinguishes it.
Temperature of Different Portions of Flame in Different Gases. (Professor V. B. Lewes.)
|
Acetylene. |
Ethylene. |
Coal Gas. |
|
|
Non-luminous zone Commencement of luminosity . . Near top of luminous zone . |
Degrees C. 459 1,411 1,517 |
Degrees C. 952 1,340 1,865 |
Degrees C. 1,023 1,658 2,116 |
ILLUMINATING VALUES OF HYDROCARBONS.
355
Temperature of the mantle of a coal gas flame is above the melting point of platinum. (Smithells.)
Hydrogen and CO only require half their volume of 0 for complete combustion, and therefore obtaining this quickly, give only a short flame. Methane requires twice its volume of O, and thus gives a flame nearly four times as long.
A flame of a given size requires a volume of gas, larger or smaller, according to the illuminating power of the gas.
The cause of luminosity in coal gas flames is not attributable to any one hydrocarbon, but to the combined action of all that are present in the gas. (Professor Lewes.)
The illuminating property of gas depends upon the presence of about 4 per cent, of unsaturated hydrocarbons.
Illuminating Value of Hydrocarbons per 5 Cubic Feet of Vapour. (Professor Lewes, 1890.)
Candles. , 240-0 . 420-0 , 741-7 , 900-0
The illuminating value of hydrocarbon gas, when consumed alone, may be approximately calculated from the heat of formation or stored-up potential energy of the elements present in each hydro- carbon.
|
Methane . Ethane Propane . |
Candles. 5-2 . . 35-7 'V . 5G-7 |
Acetylene Benzene . Toluene |
|
Ethylene . . Propene . .. • |
. . 70-0 . . 123-0 |
Napthalene |
Methane Ethane Ethylene Acetylene ,
Illuminating Value. Calculated. Found.
35-0
00-9
202-2
5-2 35-0
68-5 240-0 (Professor Lewes.)
|
Illuminat- |
Oxygen |
||||
|
iTi g Power, 5 Cubic Feet. |
per Cubic Foot Con- sinned. |
Yield C02. |
Water Vapour. |
Quantity Present in Coal Gas. |
|
|
Candles. |
Cubic Feet. |
Cubic Feet. |
Cubic Feet, |
||
|
Marsh gas . |
5-2 |
2 |
1 |
2 |
40 to 50 per cent. |
|
Ethylene . |
70 |
3 |
2 |
2 |
|
|
Benzene |
420* 820f |
7* |
6 |
3 |
|
|
Acetylene . |
400 |
2* |
2 |
1 |
Minute quantity. |
Frankland. f Knublauk.
A A 2
356
GAS EXGIXEER'S POCKET-BOOK.
Mr. W. Young has shown that where feebly luminous gas, which contains a large surplus of potential or heat energy, is carburetted, this heat energy is utilized in raising the potential of the added hydrocarbons, with a consequent increase of light.
Table Showing the Comparative Quantities of Various Gases of Different Qualities Required to Evaporate an Equal Quantity of Water. (J. Travers.)
Cannel gas
of 24 candles 1' 20
Newcastle coal gas 16-5 .
„ „ ,, . . '.'. 14-5 ;
„ „ . . . ., 13-5 ;
South Wales . . . ., 10-5 .
„ „ and 20 % cannel „ 14-0 .'
18-50 cubic feet.
19-75
20-50
21-75
22-00
22-50
28-00
23-50
The Value of Coal Gas at Different Candle Powers for Lighting and Heating. (D. Wallace.)
|
Candle Power of Gases. |
Comparative Specific Gravity. |
Value for Heating. |
Value for Lighting. |
|
14-75 26-24 33-07 |
i-ooo 1-187 1-298 |
1-000 1-295 1-496 |
1-000 1-769 2-230 |
The products of combustion of gas are, H20, caused by the com- bination of the hydrocarbons of the gas with the 0 of the air, and C02, from the combination of the C with the 0 of the air.
The proportion of sulphur in the products of the combustion of coal gas, which is converted directly into sulphurous anhydride, ranges from 89 to 99 per cent.
Cannel enriched London- 16-cnndle coal gas gives about a 3-inch flame in a " London " Argand burnei.
Carburetted water gas. 22-candle power, gives only about a 2-inch flame, owing to the presence of less methane. (Professor Lewes.)
The quantity of air admitted to the flame is principally influenced by the pressure at which the gas issues from the orifice.
5 cubic feet of gas at £{jths pressure equals 11-14 candle power.
5 cubic feet of same at ^ths pressure equals 20 candle power, (Professor W. I. Macadam.)
Size of flame from carburetted water gas is less than with coal gas for same illuminating power. (Professor Lewes,)
Light moves with a velocity of about 180,000 miles per second.
The mechanical equivalent of light equals 749 foot Ibs. per hour per candle. (Professor Julius Thomsen.)
Professor F. Clowes finds that an atmosphere of 16-4 per cent. C. 80-5 per cent. N, and 3-1 per cent. C0a will extinguish a candle, but
TEMPERATURES OF FLAMES. 357
can support a coal gas flame or life, whereas an atmosphere that will extinguish a coal gas flame will not support life.
A paraffin flame will not burn in less than 16*6 per cent. 0. A candle 15*7 „ „ 0.
A methane
AGO
A coal gas
AH
15-G „ „ 0. 13-35 „ „ 0. 11-35 ., ., 0. 5-5 „ „ 0. (Professor Clowes.)
Temperature of a Bunsen Flame.
Henry vV. J. Waggener round that the highest temperature he could get was 1,701° C. or 3,100° F., which is only a little below the melting point of platinum (1 ,780° C.).
The Temperature of Bunsen Flame. (Professor vYarburg.)
The highest temperature found was 1,704° C.
Strontium flame is rose coloured.
Sodium flame is blue green.
Mr. Macpherson showed (1878) that there was a proportionate relation between the hydrocarbons absorbed by bromine, the durability of a 5-inch flame, and the illuminating power ; and that the illuminating power and the durability bore a fixed relation to the percentage of C in the gas.
Durability test is ascertaining the time that a cubic foot of gas will make a flame 5 inches high.
With the durability test, and a jet of ^th inch diameter, and 5 inches flame, Dr. Fyfe found that the quantity consumed was directly as the square root of the pressure.
In setting the jet photometer to work it should be calibrated by means of a Bunsen photometer, and with gases of different qualities.
The water line in a jet photometer should be adjusted at least once a day by turning off the gas and letting out all pressure, and setting the hand at zero by adding more water as required.
8-8 inches — JQ — Mercury = 12 inches water pressure.
One cubic inch of mercury weighs 0-49 Ibs.
Mercury gauges are about 13 £ to 14 times shorter than water gauges.
When the two tubes of a pressure gauge are unequal the quantity of liquid displaced in each tube is equal, and in inverse ratio to their sectional areas.
Different sizes of tubes in U pressure gauges have no effect upon the correct registration of the gauge, the absolute difference of level being the same for a given pressure despite the inequality of the
358
GAS ENGINEER'S POCKET-BOOK.
Photometers, &c.
The Board of Trade Standards Department nas settled that the cubical contents of the photometries! room is not to be less than 1,000 cubic feet. This is best about 12 feet long by 9 feet wide by 10 feet high. This will take a photometer 100 inches or 60 inches long between the gas and candles. But if the room is larger it will be better for the purpose — 1,500 or 2,000 feet cubic contents are not too much.
Such ventilation is required that there shall be an ample air supply moving at a low velocity.
Ventilation of the photometer room is a very important point.
The air removed from a photometer room should be 2.000 to 3,000 cubic feet per hour.
Mr. J. Methven found that air at increasing temperatures, saturated with moisture, decreased the light emitted from a flame rapidly equals 10 per cent, between 50° and 75° F.
The area which the light covers equals 1 at 1 foot, but at 2 feet equals 4, at 3 equals 9, and at 4 equals 1 6.
I FT.
2 FT.
3 FT,
4 FT,
With the shadow photometer, square the distances of the two sources of light from the screen, and divide the one into the other.
It has been found that the normal eye can detect a difference in strength of light and shadow of fgths.
With a Kumford photometer the error in reading need not be more than ^th, and should not in usual cases be more than 1 per cent.
On a 100-inch photometer bar the divisions are more easily read than on a 60-inch one.
60-inch bar in photometer is preferable to 100-inch for ordinary gases from 14 to 30 candle power, owing to the better illumination of the disc.
If fog is present the 60-inch photometer bar is best, owing to the difference in value between the gas and candles causing the
CALIBRATING PHOTOMETER BARS. 359
greater obstruction on the one side. If the standard should be made more nearly equal this advantage of the 60-inch bar would disappear.
Formula for calculating the comparative light of two sources : divide the distance of one from the screen by the distance of the other and square the quotient.
To Graduate Photometer Bar,
100 V a"- 1 100 inches. — The distance from the candle to any mark^= — '• ^
OL — L
where a = the number to be placed upon the mark. 60 inches,— The distance from the candle to any mark = — ^-^-
To Find the Distance of any Mark in a Photometer Bar from the Standard.
Distance between lights X (v/ number of candles — 1) Number of candles — 1
= distance to mark. To prove this —
distance from mark to light2
distance from mart to standard* «*£»
With a Fixed Distance for the Standard from Disc.
\/ Number of candles X fixed distance = distance of mark
from light.
With a Fixed Distance for the Light to be Tested from the Disc.
fixed distance
= distance from standard.
vNumber of candles required
The disc should be examined that it be not too dry or too old or have been badly made ; sometimes the two sides of a Bunsen disc will give a different reading, through the different temperatures to which the sides are subjected.
The Gas Referees for London insist that 5 of the 10 tests shall be made with the one side of the disc to the gas, and the other five with the opposite side.
After making 5 of the 10 tests reverse the disc, so as to equalize any difference in colour of the two sides of the disc.
If the disc in a Bunsen photometer is made with 3 spots fixed horizontally and the disc placed slightly obliquely, the per cent, of error is considerably reduced in reading. (Mr. Heschus.)
360 GAS ENGINEER'S TOCKET-BOOK:.
A chisel-shaped crayon has been used instead of a grease-spot paper in a photometer. The crayon is cut to a chisel edge and fixed with the edge in a vertical position ; the light falling upon it through two slits in a f-inch tube in the axis of which the crayon is fixed, when the lights are even the edge disappears, and the surface appears as aflat.
A photometer has been made in which the decomposition by light of ioduret of nitrogen, prepared by the action of a pure aqueous solution of ammonia at 20° upon iodine, and noting the quantity of nitrogen produced in a given time, and the distance of the light from the liquid. (Le'on.)
For obtaining the illuminating power from the calorific value of a coal gas Mr. B. H. Thwaite recommends the following formula :
photometric value in candles calorific value — 2280
decimally graduated 352-6
the Berthelot-Mahler calorimeter being used.
The candle balance should be sufficiently sensitive to weigh gLth grain.
Photometers with sliding candles are not now stamped by the Standards Department of the Board of Trade.
Standard candles should be 8| inches from base to shoulder and are made of spermaceti with from 4 to 5 per cent, beeswax.
The Gas Referees Instructions allow the use of a candle burning within 5 per cent, of the prescribed amount.
The chief error in the amount of light emitted by a candle is due to variations in the character of the wick employed.
Variation in Light-giving Power due to Position of Wick, (J. Methvcn.)
Plane of curvature of both wicks parallel to plane of disc equals 1-999 candles.
Plane of curvature of both wicks at right angles to plane of disc and bent away from disc equals 1'957 candles.
Plane of curvature of both wicks at right angles to plane of disc and bont towards disc equals T933 candles.
The cone at the top end of sperm candles should not be used in photometry, but a good cup should be made under the wick by revolving the candle in the hand when lighted, allowing the grease to fall off, the extra length of wick should be removed. They should now be burnt until the wicks bend over, a red point is seen showing through the flame, which should be of its maximum size.
No candles should be used that gutter badly, smoke, or form badly shaped " cups " around the wick, or have the wicks greatly out of the centre, or too closely or too tightly woven wicks. The candles should burn at least 10 minutes before commencing to test, and they should be placed that the plane of the wicks are at right angles to each other.
Flames of candles vary 13 per cent, in a range of 22° F.
PHOTOMETER CANDLES, 361
Flames of Argand gas burners vary 8f per cent, in a range of 22° F. (J. Methven.)
A comparison between different candles showed a maximum varia- tion of 22-7 per cent., and in one case the average of 10 experiments gave a difference of as much as 15 per cent. (Report of Committee on Photometrical Standards, 1881.)
Candles which have been kept about 8 years show a reading about 8 per cent, higher than new candles will do.
Professor Lewes considers the candles of the present day emit less light than those in use at the time the Act was passed prescribing the standard.
At 50° F. the light from 120 grains of sperm equals 1'198 candles or + 20 per cent.
At 72° F. the light from 120 grains of sperm equals T041 candles or + 4 per cent.
In testing gas the candles having been made in a mould are taper and should therefore be cut in half, and about half inch of the wax at the middle end removed from around the wick very carefully so that the latter is not damaged. All candles burning more than 126 grains or less than 111 grains per hour should be rejected.
The spermaceti employed in the manufacture of standard candles is a mixture of solid fatty ethers and a small quantity of oil, with about 5 per cent, of beeswax to prevent crystallizing.
The gas in the photometer is to be lighted at least 15 minutes before the testings begin, and is to be kept continuously burning from the beginning to the end of the tests. The candles are to be lighted at least 10 minutes before beginning each testing, so as to arrive at their normal rate of burning, which is shown when the wick is slightly bent and the tip glowing.
To correct for any difference in the rate of burning of the candles —
average illuminating power X 600 actual time taken to burn 120 grains.
362 GAS ENGINEER'S POCKET-BOOK.
Time taken to consume 10 grains,
9'34" 9*39" 9'45" 9'S1" 957" 10'3" IO'9" lo'is" 9'3i" 9*37' 9*42" 9'48" 9'54'' 10' io'6 1012 10
IC/2 1" IO'28"
1 8'' 10*25" IO>3
41 40
Graius sperm consumed in
CORRECTING FOR IRREGULAR BURNING OF CANDLES. 363
To obtain the Correction for the Irregular Burning of the Candles by the Diagram.
Find by the sloping cross lines, the actual candle power, and immediately above the figure corresponding to the number of grains burnt in 10 minutes, or below the figure corresponding to the time taken to consume 40 grains, proceed horizontally, and note the figure above " 40 ; " this will give the candle-power corrected for the quantity of grains consumed.
The service into the photometer room from the main ought to be of small diameter, and also be of lead lined with tin or a pure tin pipe laid inside an iron one to protect it. The reason for this is that a smooth polished surface does not present any hold for napthalene to attach itself to, and it can be readily washed out with hot water.
A very important matter in relation to the supply of gas to a photometer is that the gas should come direct from the main and not through any meter before it gets to the photometer.
Photometric Standards Committee recommend that the rate of burning shall be regulated to that which gives the best value for the quality of gas used, calculation being made to bring it to the standard rate of 5 cubic feet per hour.
An Argand burner is the only one which can be relied upon to maintain a steady, vertical light in a photometer, and to give fair comparative results should the quality of the gas vary a caudle or so up and down.
Equal areas of the flames of gases, with illuminating power from 12 to 60 candles, have equal illuminating powers.
To correct for any difference in the rate of burning of the gas —
average illuminating power X 5 actual rate of burning.
364
GAS ENGINEER'S POCKET-BOOK.
EXPANSION OF GASES. 365
Diagram to find Corrected Candle-power of Gas according to Quantity burnt per hour.
To Use the Diagram. — Find the vertical line corresponding to the quantity of gas consumed in ten minutes, and the sloping curved line corresponding to the candle-power corrected from the point where these cross, proceed horizontally to the centre line, when the figures thereon will show the actual candle power corrected for the quantity of gas consumed.
Boyle's or Mariotte's Law.
The volume of a given mass of any gas varies inversely as the pressure, thus —
1 volume gas at 4 pressures =
2 „ „ ,,2 „ =
* » J5 J) •!• 5)
therefore if a volume of gas is measured at any barometrical pressure the volume at 30 indlies is
30 : observed pressure : : volume of gas : required volume.
The corrected volume of gas + water vapour for both temperature and pressure equals
observed volume X (observed pressure - tension of aqueous vapour
at observed temperature X 17-64:
observed temperature + 460.
Gas expands ^ of its own volume for every 1° C. „ „ ^ „ „ „ 1° F. (Charles's Law.)
therefore, to correct any volume of gas measured at any temperature (F.) the volume at 60° F. equals
(obaerved temperature) - 32 + 492) : (60° - 32 + 492) = 520 ::
volume : required volume.
3GG
GAS ENGINEER'S POCKET-BOOK.
To Use the Diagram. — Find the horizontal line corresponding to the barometrical pressure, and the vertical line corresponding to the temperature of the room ; at the point where these two lines cross note the tabular number by the diagonal curved lines.
Height of Barometer.
1050 1040
TO3O o
IOOO f
990 980 ~f
970 I t
960 ^
95° 94° 930 920 910
Height of Barometer.
TABULAR NUMBERS. Height of Barometer.
367
IIOO
1090 1080 1070 1060 1050 1040 1030
990
980
970
960
" * Height of Barometer. *?!
To correct for temperature and barometrical pressure, average illuminating power X 1,000
tabular number.
The "London" Argand can be used for any quality of gas up to 18 candles ; and from 18 up to 25 candles the new Preston 18-candle standard " London " Argand may be used.
The new proposal of the Standards of Light Committee is, that the rate of consumption of the gas shall be set to give a light equal to 16 candles, and the candle-power calculated from the time taken to consume ^th cubic foot (two revolutions of the test-meter drum).
368
GAS ENGINEERS POCKET-BOOK,
900
95°
Tabular Numbers.
1000 1050
looo Tabular Numbers.
HARCOURT'S 1 -CANDLE PENTANE UNIT. 369
To obtain the Correction for the Tabular Number by the Diagram.
Note the tabular number, proceed up the line immediately above these figures until it cuts the sloping line corresponding to the candle- power found by the photometer, proceed horizontally, and note the figure above the 1,000 ; this will be the actual candle-power of the gas at 60° temperature and 30-inch barometrical pressure.
Mr. Vernon Harcourt's 1-Candle Pentane Unit.
The gas used for this standard is made by bringing together in a gasholder, air and the highly volatile liquid pentane, in the pro- portion of one cubic foot of air and three cubic inches of pentane. The pentane to be used is a mixture of pentane with some paraffins of lower and higher boiling-points, and is prepared by distilling the light petroleum at 60° C., at 55° C., and twice at 50° C. The pentane thus prepared must satisfy the following tests : On agitation with ith of its bulk of fuming sulphuric acid for five minutes it must impart to the acid only a faint brown colour ; its liquid density must be between -62 and '63 at 62° F. ; the liquid must evaporate absolutely without residue at the ordinary temperature when the tension of its vapour is not less than 7'5 inches of mercury; the density of the vapour compared with air must not be less than 2'1 7, nor greater than 2-53.
The standard 1 -candle pentane unit burner consists of a brass tube 4 inches in length and 1 inch in diameter, which the gas enters towards the bottom. The upper end of the tube is closed by a brass plug ^ inch in thickness, in the middle of which is a round hole £ inch in diameter. Around the burner is placed a glass cylinder, 6 inches by 2 inches, the top of which is level with that of the burner, air entering through the gallery on which the chimney stands. Above the burner is supported, at a height of 63'5 millimetres, a piece of platinum wire about 0'6 millimetres in diameter, and from 2 to 3 inches in length. The air gas passes through a small meter delivering at each revolution ^th of a cubic foot, and then through a small governor fitted to regulate the flow to 0'5 cubic foot an hour. The height of the flame is adjusted by means of a delicate stop-cock until the top of the flame appears to touch, but not to pass, the horizontal platinum wire which is adjusted so as to /be exactly over the flame and to extend not less than half inch beyond it.
A Sugg 16-eandle Standard Burner gives only about 0'6 per cent, of the full mechanical equivalent, while a Welsbach incandescent burner only gives Ivl per cent., while electricity only employs about the same per cent, of the original heat energy of the coal used for generating. (Dr. H. Morton.)
The burner used for Dibdiri*s 10-candle pentane standard is a modification of Sugg's standard '' London " Argand burner.
The height of the screen in the 10-candle pentane standard should be 2'15 inches above the steatite.
G.E. B B
370 GAS ENGINEER'S POCKET-BOOK.
Herr Von Hefner- Alteneck's Standard of Light.
_ The unit of light should be a free burning flame, in still pure air, supplied by a section of solid wick and fed with amyl-acetate ; the wick-tube to be circular and of German silver, measuring 8 millimetres internal diameter, 83 millimetres external diameter, 25 millimetres high.
Flames to be 40 millimetres high, measured from the edge of the wick-tube at least 10 minutes after lighting the lamp. A variation of 0*02 is allowed in the light measurement.
The German standard candle with a 45 millimetre flame
Hefner unit
English standard candle Hefner unit
= 1-14.
The amyl-acetate lamp, devised by Herr Hefner-Altcucck. is practically a spirit lamp burning the vapour of amyl-acetate. The wick is contained in a round tube of German silver, 8 millimetres in diameter and 25 millimetres high. It is formed of a strand of cotton yarns, and is so regulated as to produce a flame 40 millimetres in height. It is supposed to give a light equal to one candle, but Mr. Dibdin found that the height must be increased to 51 milli- metres to equal the light of one candle by the Methven standard.
The Carcel (French photometrical standard) is now proved to be 10 candles (English standard) as against the hitherto variously estimated 9-2, or 9'5, or 9*8 candles. (Journal of Gas Lighting, July llth, 1893.)
Messrs. Kirkham and Sugg found the carcel to equal 9'6 candles.
Table Showing the Illuminating Power of Different Gases after Carburetting with Gasolene in the same Carburettor.
(J. Methven.)
Quality of Quality of
Gas before Gas after
Carburettiiig. Carburetting.
10-1 .... 73-98 average of 2 tests. 10-0 .... 71-18 „ 2 ., 16-0 .... 70-05 ., 3 ., 22-0 .... 67-77 M 2 '., 27-5 .... 70-09 „ 2 „
It will be noticed that the resulting quality of the gas is about equal in each case.
Mr. Vernon Harcourt's 1-oandle pentane unit burner consists of a brass tube 4 inches in length and 1 inch in diameter, the upper end of which is closed by a brass plug £ inch in thickness, in the middle of which is a round hole £ inch in diameter. A glass cylinder 6 inches long x 2 inches in diameter is placed with the top level with that of the burner, air entering at the bottom. A piece of platinum wire,
DIBDIN'S 10-CANDLE PENTANE STANDARD. 371
about 0-6 millimetres diameter, is fixed at 63-5 millimetres above the burner. The air gas is delivered at the rate of about half a cubic foot per hour, and the flame is adjusted so that the tip just touches the platinum wire. The gas is a mixture of 1 cubic foot of air and 3 cubic inches of pentane. The pentaue used is mixed with a distillation of the lighter petroleums at 60° C., at 55° C., and twice at 50° C., and must pass the following tests : It must be of '62 to -63 liquid density at 62° F., and when agitated with 5 per cent, by volume of fuming sulphuric acid for 5 minutes, must only turn the acid a faint brown colour. It must entirely evaporate at ordinary temperatures when its vapour tension is above 7*5 inches of mercury. Its vapour density must be between 2-4:7 and 2-53. In regulating the height of the flame the eye should be screened from the luminous portion of the flame.
As long as the bottom of the carburettor is covered by the pentane it does not matter what depth of the liquid is present.
With the 10-candle standard the light is constant between 42° and 75° F.
Pentane, 1 volume, air 576 volumes, measured at 60° F. ; or as gases, 20 volumes of air to 7 of pentane gas.
Pentane is a product of the distillation of petroleum spirit, having a specific gravity of '630 and can be made always exactly alike ; a certain quantity of pentane will be taken up by atmospheric air if allowed to pass over its surface.
The pentane employed to produce the air gas used in Mr. Harcourt's 1-candle standard and in the carburettor of the 10-candle pentane Argand was obtained by purifying light -petroleum by the successive action of sulphuric acid and soda solution, and then distilling at 60° C., at 55° C., and twice at 50° C.
Dibdin's Pentane Argand Burner Dimensions.
Number of holes .... 42
Diameter „ 0*028 inches = 0! 71 millimetres
Inside diameter of steatite . . 0*390 ., = 9*9
Outside „ „ . . 0-750 „ = 19*05 Diameter of inside of metal cone
at top 0-930 .. = 23-62
Chimney length . . . 6*000 M =152-4
Chimney, inside diameter . . 1-5 .. = 33-1
Height of cut-off .... 2'15 ,, = 54*61
The centre of the flame should be immediately over the terminal of the photometer bar.
Dibdin's 10-Candle Pentane Argand Air Gas Standard.
The burner is a specially constructed tri-current Argand burner, the annular steatite ring being perforated with 42 holes, each hole being 0-71 millimetre in diameter. The inner perforated cone is punctured with ten apertures 0*25 inch in diameter. The dimensions of the chimney being 6 inches high and 1£ inches inside, the top of the flame should be maintained as nearly as possible at three inches
B B 2
372 GAS ENGINEER'S POCKET-BOOK.
above the steatite. The middle portion of the screen is cut away so as to leave, above the top of the steatite burner, an opening 2'15 millimetres in height and 1*4 inches in width, the lower portion of this opening being exactly level with the top of the steatite.
The carburettor for the 10-candle pentane Argand consists of a circular vessel constructed of tinned plate 203'2 millimetres (8 inches) in diameter and 50'8 millimetres (2 inches) in depth, having a spiral division 25-4 millimetres (1 inch) in width. This division is made by soldering in a spiral strip of metal 4 feet 6 inches in length and 2 inches wide, gas-tight to the under side of the top of the carburettor, so that when the top is fixed on, the bottom of the strip comes close to the bottom of the vessel and is sealed by the pentane, so that the air has to pass over pentane for a distance of about 4 feet 6 inches, and becomes thoroughly saturated. At the end of the spiral division, near the side of the carburettor, a bird fountain is fixed for charging the carburettor and keeping it charged at a constant level with liquid pentane. The lower end of the inlet fountain is closed, and rests upon the bottom of the tank. Through the side of the tube, which is 0'4 inch (lO'l millimetres) in diameter, 16 holes, 1 millimetre in diameter, are bored, close to the bottom, and through these the pentane enters the carburettor. At one side of the inlet-tube, 1 inch from the lower end, a small tube 8 millimetres in diameter and 20 millimetres in length is connected thereto and turned upwards. The fountain inlet-tube is carried up through the top of the carburettor, and continued in the form of a bulb having a capacity of about 200 cubic centimetres.
When the carburettor is being charged the gas must be ex- tinguished, to avoid the risk of the vapour firing and causing an explosion.
To Test Lime for its Purifying Value. — Take a small quantity of lime, weigh and add sufficient water to slake ; dry and re-weigh, when increased weight shows quantity of water required to convert the caustic to hydrate ; then, as 56 parts caustic lime will absorb 18 parts water, the percentage of the former can easily be ascertained.
To test if lime has been thoroughly burnt, add dilute hydrochloric acid, when no great effervescence should be given off.
To Find the Quantity of C0.2 or H2S that a Sample of Lime will absorb —
per cent, pure lime
5 X . T~Kn =s= number of cubic feet of COa
or H2S absorbable.
1 Ib. pure Fe208 will unite with 0-603 Ib. or 6-7 cubic feet H2S. Water will take up ?igth of its weight of lime, and is then saturated. When limestone is burnt the C02 is expelled as per equation — CaC03 = CaO + C02.
One part pure CaOH20 will unite with -586 parts C02, or -453 H2S, or 1 Ib. pure lime will unite with 5 cubic feet of either C02 or H2S.
To Test Caustic Lime. — Take a sample of known weight and thoroughly slake it, dry in an air bath at 250° F., and weigh ; the
TO TEST OXIDE OF IRON. 373
increase of weight will indicate the quantity of water taken up in rendering the caustic lime into hydrate. Nine parts of water will be absorbed for every 28'5 grains caustic lime, then
28-5 x difference in weight
— - Q — - = quantity of caustic lime.
If, however, any of the lime has absorbed moisture from the air, this will not show it.
Hydrated peroxide of iron equals Fe203, 3 H20, which unites with 3 H2S to form 2 FeS + 0 H20 -f S, and on revivification 2 FeS + 3 H20 + 30 equals Fe203, 3 H20 + 2S. Sulphate of iron equals FeO, S03, which unites with H2S and NH3 to form FeS + NH40, S03.
Lime equals CaO, which unites with the equivalent of H20 to form CaOH20, equals hydrate of lime, which combines with C02 to form CaOC02 + H90, or with H2S to form CaS + 2H20.
When lime which has taken up H2S and become CaS + H20 is presented to C02 it becomes CaOC02 + H2S, the H2S being driven off, owing to the greater affinity of CaO for C02.
Sulphide of lime (CaS) combines with CS2 to form CaS, CS2 equals sulphocarbonate of lime, which requires a longer contact for combination than is necessary with H2S or C02.
Hydrochloric acid will dissolve hydrated ferric oxide, but has little effect on anhydrous ferric oxide.
To Test Spent Oxide of Iron, Lime, or Weldon Mud for Sulphur. — Dry the sample at 212° F. until a constant weight is obtained, then place in a test tube with a little cotton wool at the bottom, pass a quantity of CS2 (about three or four times the bulk of the oxide) through it, and allow the solution to fall into a flask, evaporate the CS2 with heat, when the S will remain in the flask and the quantity can be easily found.
Mr. A. J. Bale proposed to so arrange the apparatus for testing spent oxide for sulphur that the bisulphide of carbon is evaporated and condensed, and then to pass through the oxide to the evaporating flask to again go through the cycle until all the sulphur has been removed from the oxide, and by this means reduce the quantity of bisulphide necessary.
When testing oxide by the bisulphide method, care should be taken that the oxide has been thoroughly revivified.
Place dilute hydrochloric acid in a wide-mouthed bottle and stand in this a small vessel containing the spent oxide, connect to measuring tube immersed in water, overturn the oxide into the acid, when the quantity of H2S driven off will be found by the displacement of the water in the measuring tube. Twenty-five grammes spent oxide is the best amount, and, when fresh from the purifier, will evolve about 250 cubic centimetres of H2S.
Four days will usually suffice to revivify oxide.
Temperature of oxide while revivifying, and in presence of ample moisture, may reach 140° to 160° F.
One ton of good oxide should purify 1| to 1J millions cubic feet before becoming spent.
374
GAS ENGINEERS POCKET-BOOK.
Beckton Purifying Method. 2 carbonate vessels for the elimination of C02 2 oxide „ „ ., H2S
2 sulphide ,, „ ,. CS2 etc.
2 weldon mud „ „ „ H2S driven off from
sulphide vessels.
100 Volumes Water at 60° F. and 30 Inches Barometer will absorb —
Ammonia . Sulphurous acid H2S . . C02 defiant gas
Volumes. 78,000 3.300 253 100 12-5
Volumes. '7 •56 •66 •56 •60
Oxygen
CO
N
H
Light carburetted hydrogen
(Dr. Franklaud.)
One volume H20 at 0° C. dissolves 4-37 volumes H2S. H2S unites with an equal weight of NH3. 22 parts C02 unite with 17 parts NHS.
Quantities of Gases Absorbed by Water at 20° C. at 760 Millimetres
Pressure.
'Hydrogen . . 1-9 per cent, of the volume of water.
N . . . . 1-4
0 ... 2-9
Methane . . 3-5
GO ... 2-3
C02 . . . 90-0 Ethylene . . 15'0
Acetylene . . 95*0 H2S . . . 291-0 NH3 . . . 74,000-0
To Find the Amount of C02 in Gas Liquor.
Add an excess of barium chloride to a known quantity of gas liquor, digest for 30 minutes at a gentle heat, filter, then dry, ignite, and weigh the precipitate. Every 98*5 parts of barium carbonate contains 22 parts C02.
To Estimato the Quantity of Free Ammonia in Liquor. Take a glass measure graduated into 16 parts, fill with liquor and empty into a glass beaker, rinse the measure with distilled water and add rinsings to liquor in beaker with a few drops of methyl orange indicator. Rinse the measure with a little 10 per cent, acid solution and throw away rinsings, fill up measure with 10 per cent, acid solu- tion (specific gravity, 1,064-4 at GO0 F.), and pour acid very gradually into beaker until the liquor is neutralized. The number of divisions of acid solution used equals ounces strength of liquor.
To Estimate the Quantity of Ammonia in Liquor. Mix a known quantity of the liquor with an excess of caustic lime or soda, heat, and lead the evolved fumes of ammonia through a solu-
10 PER CENT, ACID SOLUTION,
375
tion of sulphuric acid (10 per cent.) until all the gases of ammonia are evolved, titrate the acid solution with 10 per cent, alkaline solu. tion, note quantity of latter necessary to neutralize, deduct from quantity of acid solution used, equals strength of ammonia in liquor,
Ounces strength of ammoniacal liquor is the number of ounces by weight of HaS04 (specific gravity 1,064*40 at 60°) required to neutra* lize a gallon of the liquor,
To convert degrees Twaddell to specific gravity (water equals 1)— (Degrees X -005) + 1,
To convert specific gravity into degrees Twaddell— Deduct J and divide by '005,
Every ounce strength of ammoniacal liquor equals '347 ounces of absolute ammonia,
Specific Gravity of 10 per cent. Acid Solution at Various Temperatures. (L. T. Wright.)
|
Temperature. |
Specific Gravity. |
Temperature. |
Specific Gravity. |
Temperature. |
Specific Gravity. |
|||
|
F. |
c. |
F. |
C. |
F. |
C. |
|||
|
40 |
4-45 |
1068-10 |
54 |
12-23 |
1065-64 |
68 |
20-00 |
1062-72 |
|
41 |
5-00 |
1067-94 |
55 |
12-78 |
1065-45 |
69 |
20-56 |
1062-51 |
|
42 |
5-56 |
1067-78 |
56 |
13-34 |
1065-24 |
70 |
21-11 |
1062-30 |
|
43 |
6-11 |
1067-62 |
57 |
13-90 |
1065-03 |
71 |
21-67 |
1062-08 |
|
44 |
6-67 |
1067-46 |
58 |
14-45 |
1064-82 |
72 |
22-23 |
1061-86 |
|
45 |
7-23 |
1067-30 |
59 |
15-00 |
1064-61 |
73 |
22-78 |
1061-64 |
|
46 |
7-78 |
1067-12 |
60 |
15-56 |
1064-40 |
74 |
23-34 |
1061-42 |
|
47 |
8-34 |
1066-94 |
61 |
16-11 |
1064-19 |
75 |
23-90 |
1061-20 |
|
48 |
8-89 |
1066-76 |
62 |
16-67 |
1063-98 |
76 |
24-45 |
1060-97 |
|
49 |
9-45 |
1066-58 |
63 |
17-23 |
1063-77 |
77 |
25-00 |
1060-74 |
|
60 |
10-00 |
1066-40 |
64 |
17-78 |
1063-56 |
78 |
25-56 |
1060-51 |
|
51 |
10-56 |
1066-21 |
65 |
18-34 |
1063-35 |
79 |
26-12 |
1060-28 |
|
52 |
11-11 |
1066-02 |
66 |
18-89 |
1063-14 |
80 |
26-67 |
1060-05 |
|
58 |
11-67 |
1065-83 |
67 |
19-45 |
1062-93 |
85 |
29-45 |
1058-95 |
Test for Sulphuretted Hydrogen,
The gas is dried and passed through U tubes containing cupric phosphate on one side and non-alkaline calcium chloride on the other, the difference in weight of the U tube giving the quantity of sulphuretted hydrogen in the amount of gas passed. (L. T. Wright.)
Another Test for Sulphuretted Hydrogen.
The gas is made to bubble through an acid solution of cadmium chloride in two or three Woulffe's bottles, when cadmium sulphide is precipitated, which may be washed, filtered and weighed, and the quantity of H2S thus obtained.
Sheard's Test for Ammonia, H .S and CO, in Gas. Four absorption tubes are required and a filter tube containing cotton wool to absorb tarry matters when testing crude gas, In the
376 GAS ENGINEER'S POCKET-BOOK.
first tube a certain quantity of half cleci-normal strength sulphuric acid is placed; in the second a quantity of cupric sulphate 1 part and water 10 parts (30 cubic centimetres of this should absorb all the H2S from 500 cubic centimetres crude gas) ; in the third and fourth tubes, say, 30 cubic centimetres and 20 cubic centimetres of barium hydrate. The first tube is the test for NH3, the second for H0S, and the other two for C02. Pass, say, 500 cubic centimetres of gas slowly through the apparatus, and then 1 ,000 cubic centimetres of air to ensure that the whole of the gas has passed over the whole of the apparatus. Wash out the glass scrubber of each absorption tube with a little distilled water. Titrate the contents of the first tube
with ^rr ammonia HO, using cochineal as an indicator, note the
quantity required to neutralize, and deduct this from the quantity of sulphuric acid placed in the tube X 74 = grains of ammonia per 100 cubic feet gas. Titrate the second tube with similar ammonia solution, and use methyl orange as indicator X 74 = grains H2S per
100 cubic feet gas. (Each cubic centimetre ^ acid = 74 grains NH3 per 100 cubic feet of gas. Each cubic centimetre — ammonia re- quired to neutralize = 74 grains H2S per 100 cubic feet gas.) Titrate the washings of the third and fourth tubes with |^HC1, deduct the
quantity required to neutralize from equivalent of — Ba HO, first put in tube X 0*24 = volumes per cent, of C02.
Harcourt's Colour Test for H2S.
Here the gas is passed straight through the acetate of lead solution until the correct colour is obtained, when the quantity of gas passed contains 0-0025 grains S, and as S exists in H2S in the proportion of 32 to 2 H by weight, the quantity of H2S can be readily found.
Harcourt's Colour Test for CS2.
The gas containing CS0 is made to pass over heated platinised pumice, when the equivalent amount of H2S is formed and made to bubble through a solution of acetate of lead until the latter is turned to a brown shade of a certain tint, when the quantity of gas passed over the pumice is noted, and to effect this an amount of H2S equal to 0'0025 grains S must have been in the gas, from which the quantity per 100 cubic feet may be ascertained. 7 or 8 grains per 100 cubic feet should be added to the quantity found by above test for other sulphur compounds not acted upon by above method.
If the gas is not already freed from H2S it must be passed through an oxide purifier before being allowed to get to the pumice.
A diagram to facilitate the calculation of S from the divisions of the measuring cylinder commonly used, which latter equal cubic feet is shown.
HARCOURT'S COLOUR TEST.
Diagram for use with Harcourfs Colour Test,
500
Grains of Sulphur
Divisions of Measuring Cylinder.
50 40 30 20 10
Grains of Sulphur per 100 Cubic Feet of Gas,
378 GAS ENGINEER'S POCKET-BOOK.
To Test for Presence of Acetylene.
/ Bring the gas into contact with ammoniacal cuprous chloride solution when red acetylide of copper is formed ; aspirate the gas into a flask containing the blue cuprous chloride, agitate, and, if acetylene is present, the sides are at once coated with the red compound.
Test for CO..
The gas is bubbled through a small orifice under lime water, made by mixing slaked lime and water and decanting the clear liquid when time has been allowed for the mixture to settle. If C02 is present in the gas the lime water becomes milky.
Mr. J, T. Sheard's Test for C0.2.
Charge two absorption tubes with 20 or 30 cubic centimetres each dcci-normal barium hydrate solution ; pass 500 cubic centimetres of gas through, then immediately 500 cubic centimetres air. Wash out the absorption tubes, add a few drops phcnol-phthalein and titrate with deci-normal hydrochloric acid. Deduct quantity of acid re- quired to neutralize from equivalent of barium hydrate used equals amount of C02 absorbed from 500 cubic centimetres of gas —
X 0'241 = per cent, by volume X 1'92 = grains per cubic foot
0-0022 gramme C02 is equivalent to 1 cubic centimetre of deci- normal acid.
0'914 gramme equals weight of 500 cubic centimetres of C0n saturated with moisture.
28,315 cubic centimetres equals value of 1 cubic foot.
15,432 grns. equals value of 1 gramme.
To Detect Oxygen or Air in Coal Gas. — Fill a graduated glass with gas and then bring in contact with a solution of pyrogallic acid, made alkaline with caustic potash ; when oxygen is absorbed, the rise of the acid in the graduated tube showing the quantity of oxygen absorbed from the gas, this quantity X 5 equals quantity of air.
The quantity of oxygen is usually obtained by subtracting the weight of all the other constituents from the original weight of the substance being analysed.
To Convert Percentage of C02 and H..S into Cubic Inches per Ga'llon.
For Co2 , for H2S
-
0-47 0-3G4
Methods of obtaining Specific Gravity of Gases.
Direct Method. — Weigh a hollow vessel, in an exhausted state, then filled with air, and afterwards, when filled with the gas under test, weight of air ~ weight of gas equals specific gravity.
SPECIFIC GRAVITY OF GASES. 379
Aerostatic Method.— A balloon of, say, 1 cubic foot capacity is filled with the gas and the balloon weighted until it is just prevented rising in the air. Weight of air displaced by balloon - weight of balloon when weighted equals weight of gas ; then weight of air dis- placed -f- weight of gas equals specific gravity.
Effusion Method. — If any gases are expelled at same pressure through a small aperture in walls of minute thickness the squares of the velocity of expulsion are in inverse ratio to the specific gravity of the gases.
Liquid Balance Method. — If the lower end of a tube of some length be immersed in liquid the height of the liquid in the tube will vary according to the specific gravity of the gas in the tube.
Hydrometer Method. — Place a hydrometer, with a hollow glass ball, hermetically sealed at top, into a glass cylinder partly filled with water, and cover all with a further glass bell and pass gas through the latter so that hydrometer ball is surrounded by the gas, when the hydrometer will rise and fall according to the specific gravity of the gas.
Lux's Gas Balance Method. — Pass air through the globe and note the position of pointer, and move scale to equal 1OO, then pass gas through and note the position of pointer, and the figure against same at pointer equals specific gravity of gas. The sensitiveness of the apparatus can be increased by, or diminished by, raising or lowering the centre of gravity of the balance from the centre of motion.
To Determine the Specific Gravity of a Gas, (Greville Williams.)
Pass air through one bottle potassium hydrate solution, two bottles sulphuric acid, (5 U -tubes of very active soda-lime, and 4 U -tubes of calcic chloride, and then through a glass globe with stop-cock at each side, and after passing through the globe through one more tube of calcic chloride. The air should be drawn through by an aspirator until the weight becomes constant and temperature regular. Shut tap of globe on aspirator side and remove rubber connection on that side and then close the other tap. Wipe the globe with a silk hand- kerchief and hang by platinum wire to one side cf a balance. Counterpoise with globe of a little smaller capacity, using weights to exactly balance. Note these weights required and call weight of balloon and air.
Pass the gas to be tested slowly through 6 U -tubes of soda-lime to remove all trace of C02, and through 4 tubes of calcic chloride for one hour, then through the globe with a further tube of calcic chloride on outlet. Shut off the inlet tap and then immediately the outer tap. Fix and weigh as before equal to weight of balloon and gas.
Specific gravity of the gas equals capacity of balloon or globe in cubic centimetres multiplied by weight of 1 cubic centimetre air at the temperature in °C. of the test, less the difference in weight of the balloon divided by the capacity of the balloon multiplied by weight of 1 cubic centimetre air.
380 GAS ENGINEER'S POCKET-BOOK.
To Obtain the Specific Gravity of any Coal, Weigh a small piece in and out of distilled water (62° F.) then
. Weight in air ==specific gravitv.
loss of weight when weighed in water
Specific gravity of any substance X 1,000 equals weight in ounces (avoirdupois) per cubic foot.
To Obtain Value of Gas in Grains Sperm per Cubic Foot. Illuminating power x 120
To Obtain Value of Coal per Ton in Ibs. Sperm,
Value in grains sperm per cubic foot x cubic feet made per ton
7,000 or,
Cubic feet made per ton
— ^ — — X illuminating power X 3
175~~
Average Analysis of Bituminous Coal.
Caking. Non-caking.
Specific gravity . . . 1-267 1-279
C 80-05 77-19
H 5-92 5-20
O 8-98 32-01
N 2-21 1-81)
S 1-13 -f>4
Ash 1-72 3-02
Determination of the Caking of Coal, (Louis Campredon.)
The coal is powdered to pass through a sieve of 2.580 meshes per square inch, and a fixed quantity — say 1 gramme — of it is mixed with various amounts of uniformly fine sand. Each sample of coal and sand is heated to redness in a small porcelain crucible, and the character of the residue is observed when cool. From the various samples, the maximum quantity of sand which may be added to the given weight of coal with the production of a firm cake on heating is found. The weight of coal is taken as unity in the scale of comparison ; and the caking power of coal which leaves a powdery residue is of course nil. The highest result found with any coal was 17° on this scale ; pitch gave 20°.
The illuminating power of 140 samples of caking coal varied from 12-5 to 18-5 candles, and the quantity purified by 1 cwt, lime varied from 10,000 to 18,000 cubic feet,
TESTS OF COAL.
381
Table Showing the Changes Wood Undergoes in Becoming Coal. (Roscoe and Schorlemmer.)
|
C. |
H. |
O and N. |
|
|
Wood .... |
50-00 |
6-00 |
44-00 |
|
Irish peat .... |
60-02 |
5-88 |
34-10 |
|
Lignite from Cologne . |
66-96 |
5-25 |
27-76 |
|
Earthy coal from Dax |
71-20 |
5-89 |
19-90 |
|
Cannel coal from Wigan |
85-81 |
5-85 |
8-34 |
|
Newcastle Hartley . |
88-42 |
5-61 |
5-97 |
|
Welsh anthracite . |
94-05 |
3-38 |
2-57 |
|
Graphite .... |
100-00 |
o-oo |
o-oo |
Average Analysis of Welsh Anthracite. (J. Hornby.)
Per Cent.
Fixed carbon 89'84
Ash 1-20
Sulphur 0-80
Moisture 2 '25
Volatile matter 6 '01
Lignite specific gravity equals 1'15 to 1-3. Bituminous coal, specific gravity equals 1'25.
Tests of Coal.
Dry coal at 100° C., weigh every 2 hours, and note lowest weight to obtain amount of moisture.
To obtain quantity of coke or volatile matter, weigh coal in platinum crucible, burn off over powerful Bunsen flame until all gas is driven off, allow to cool in dessicator and weigh ; residue = coke. Original weight - coke = gases.
To estimate quantity of ash, weigh coal in a platinum boat and heat it in a glass tube to red heat, air being slowly drawn through the glass tube ; cool and weigh boat.
To find total quantity of sulphur, weigh coal with four times its weight of sodium and potassium carbonates mixed in molecular pro- portions in platinum crucible. Heat over Argand spirit lamp, and slowly increase to just below visible redness until coal becomes faintly grey, then raise heat to a faint red for 40 to 60 minutes ; cool.
Products of Distillation of 1 Ton Newcastle Coal. (Gesner.)
Temperature of Distillation,
1,000° to 1,200° P.
Gas . . 7,450 cubic feet. Tar . . . 18i gallons. Coke . . 1,200 Ibs.
Products of the Tar. Benzol . . .3 pints. Coal tar naphtha . . 3 gallons. Heavy oil and naph- thalene . . .9
Temperature of Distillation,
750° to 800° F.
Gas . . 1,400 cubic feet Crude oil . . 68 gallons. Coke . . 1,280 Ibs.
Products of the Crude Oil.
Eupioii . . .2 gallons. Lamp oil . . . 22£ „ Heavy oil and
in . .24
382
GAS ENGINEER'S POCKET-BOOK.
Composition of Fuels (Ash being Deducted). (Sir H. Roscoe.)
|
Description of Fuel. |
Percentage Composition. |
||
|
C. |
H. |
N and O. |
|
|
1. Woody fibre 2. Peat from the Shannon . . 3. Lignite from Cologne . . ^ 4. Earthy coal from Dax . {- ..,',» ; 5. Wigan caniiel 6. Newcastle Hartley . . i 7. Welsh anthracite . . . . |
52-65 60-02 66-96 74-20 85-81 88-42 94-05 |
5-25 5-88 5-24 5-89 5-85 5-<;i 3-38 |
42-10 34-10 27-76 19-90 8-34 5-97 2-57 |
The above shows the alteration in composition which wood has undergone in passing into coal.
Average carbon in average gas coke equals 88 per cent. Average carbon in average anthracite equals 90 per cent.
The 0 in purified coal gas does not result from the distillation of the coal, but must have been admitted with the air either inten- tionally or accidentally.
Gas only forms about 15 per cent, of the total products obtained from the distillation of coal.
Experiments on small quantities of coal usually give results 7 per cent, in favour of the coal over working results.
Sulphur in Coal. (J. Hepworth.)
|
Sulphur in Volatile Products per Ton |
Sulphur in Coke per Ton of |
Total Quantity of Sulphur per Ton |
|||||
|
of Coal. |
Coal. |
of Coal. |
|||||
|
Lbs. |
Percentage. |
Lbs. |
Percentage. |
Lbs. |
Percentage. |
||
|
"ei |
A |
4-35 |
•19 |
8-51 |
•38 |
12-86 |
•57 |
|
o |
T> |
7-84 |
•35 |
4-92 |
•21 |
12-76 |
•56 |
|
C |
4-70 |
•21 |
7-61 |
•34 |
12-31 |
•55 |
|
|
0 |
D |
18-16 |
•81 |
15-0 |
•67 |
33-16 |
•48 |
|
a |
E |
9-18 |
•41 |
6-04 |
•27 |
15-22 |
•68 |
|
0 |
F |
9-04 |
•44 |
7-76 |
•31 |
16-80 |
•75 |
Average sulphur per Left in coke
ton of coal, 13'80 Ibs.
Removed by purification from volatile products Coal
6-53 Ibs. 7-27 „ 13-80 ,
Bituminous coals contain sulphur, principally combined with iron, in the form of bisulphide of iron (FeS2) or pyrites which become sulphide or protosulphuret of iron (FeS) on the application of heat.
Coal gas contains about 7 per cent. CO.
According to the Gas Referee's Reports gas always contains about 10 grains sulphur per 100 cubic feet when sent out.
The whole of the sulphur in coal gas is converted into sulphur dioxide during combustion. (W. C. Young.)
GRAINS OF BARIUMSULPHATE CORRECTED.
383
Diagram showing Grains of Sulphur per 100 Cubic Feet for each Grain of Barium Sulphate (corrected for Temperature and Pressure),
Tabular Numbers. 1040 1020 1000 980 960 940 920 9°°
8 I
o>
I
7 -3 in
£
• 1
o
5 | O
384 GAS ENGINEER'S POCKET-BOOK:.
To Estimate Lbs. of Prussian Blue in Gallons of Cyanogen Liquor.
Filter small quantity of liquor, take 5 cubic centimetres, acidify with dilute HC1 (1 part HC1, 3 H20), precipitate the Prussian blue with, a slight excess of Fc^G\6 (ferric chloride) solution.
Collect precipitate on niter, wash till free from acid, and dry at 100° C.
"Wash the dried precipitate with previously dried CSa (that is CSa not in contact with water) and allow to stand until" the C82 has drained off or evaporated, and return it to drying oven until quite dry ; cool and weigh.
Weight in gas X 2 = pounds per gallon.
Per cent, of HCNS 2-62, NH3 1-87, K4 FeCy6 + 3aq TrlO, from analysis of twelve samples of spent oxides in Germany. (J. V. Esop.)
Some of the N in the coal combines with two equivalents of carbon to form cyanogen, which unites with sulphide of ammonium to form sulphocyanide of ammonium.
If spent oxide be burned for making H2S04 the cyanogen com- pounds cannot be recovered.
Spent oxide has been found to contain, with 25 per cent, sulphur, 12 £ per cent. Prussian blue.
ENRICHING PROCESSES. 385
ENRICHING PROCESSES.
Relative Cost of Enrichment from 16 Candles to 17-5. (Professor Lewes, 1891.)
By Cannel (Livesey) 4'OOd. = 2'667/7. per caudle per 1,000 cubic feet .", Pintsch gas . . 3 64 = 2-427 „ „
„ Oil gas (Foulis) . 2-34 = 1-560 „ ., „
„ Maxim-Clark pro- cess . . . 1-64 = 1-093 „ Carburetted water
gas . . . 1-01 =0-673 .. ., „
„ Tatham Oxy-oil
process (probable) 0-91 = 0-607 ., „ .,
„ Tatham Oxy-oil
process (claimed) 0'50 = 0-333 „ „ „
Peebles process said to give 1,750 candles per gallon. Water gas process said to give 1,400 candles per gallon. Carburine, gasoline and benzol said to give 1.000 candles per gallon. Pintsch gas, liquid from compression, said to give 3,000 candles per gallon.
Gas enriched 1 Candle by 1 Gallon of the Liquid.
Benzol (chemically pure) . . • . 13,300 cubic feet.
Benzol (90 per cent.) .... .12.500 „
Carburine (specific gravity -680) . . . 5,700 „ Common petroleum spirit (specific gravity -700) 4 ,300 „
(T. Stenhouse.)
With 5 per cent, petroleum vapour there is no danger of explosion : with 6 -25 per cent, a feeble report ; with 8-30 per cent, a loud report ; with 11 to 14 per cent, a violent report ; with 20 per cent, no explosion. (Journal of Gas Lighting.}
70 per cent, by bulk of producer gas lowers the flame temperature of water gas 400°. (Walter Clark.)
The lower the gas in illuminating power the more it costs to improve it.
Mr. Foulis considers undiluted oil gas is better for enrichment and more economical than carburetted water gas.
In distilling shale oil the gas has to be rapidly drawn off, or it would become permanent.
Oxygen (up to \ per cent.) added to pure gas increases the illu- minating power (see Gas Journal, 1885, " Midland Association "). (B. W. Smith.)
Formula to find Proportion of Enriching Gas Required.
Initial candle-power <x> candle-power desired
Initial candle-power <x> candle-power of enriching gas
= percentage required. G.E. C C
386
GAS ENGINEER'S POCKET-BOOK.
Formula to find Quantity in Cubic Feet to be added to Initial 1,000 Cubic Feet.
1,000
Initial candle-power <x> candle-power desired Candle-power of enriching gas co candle-power desired = quantity in cubic feet per 1,000.
If gallons carburine (specific gravity 68) per 10,000 cubic feet gas required to enrich 1 candle by Clark carburettors.
Enriching Value of Oil Gas due to Temperature of Distillation, (W. Foulis.)
|
Coal Gas. Illuminating Power, cor- rected to 5 Cubic Feet per Hour. |
Oil Gas. Illuminating Power, cor- rected to 5 Cubic Feet per Hour. |
Percentage of Oil Gas added. |
Illuminating Power of oombinudGas corrected to 5 Cubic Feet per Hour. |
Enrichment Value of Oil Gas calcu- lated to 5 Cubic Feet. |
Average Retort Tempera- ture. |
|
20-74 |
64-05 |
4-20 |
24-28 |
105-20 |
1.100° K. |
|
20-45 |
60-88 |
4-90 |
23-69 |
86-60 |
1.135° F. |
|
18-51 |
62-11 |
4-52 |
21-59 |
86-60 |
1,145° F. |
|
16-84 |
61-10 |
4-88 |
20-85 |
108-30 |
1,070°F. |
|
14-65 |
74-00 |
4-00 |
19-77 |
117-00 |
1,000° F. |
Gasoline boils at about 40° C.
Carburine boils at about 67° C. Specific gravity 0-680.
Benzene boils at about 80-5° C. Specific gravity 0-885 at 15° C.
Russian mineral oil (-908 specific gravity) contains 20'5 grains sulphur per gallon.
Russian burning mineral oil contains 10-3 grains sulphur per gallon.
American „ „ „ 16-3 ., „ „
American water white mineral oil contains S'l grains sulphur per gallon.
American burning safety mineral oil contains 14-0 grains sulphur per gallon.
Scotch mineral oil (for gas making) contains 49'8 grains sulphur per gallon. (W. Fox and D. G. Riddick.)
Petroleum contains about 85 per cent. C, 13 per cent. H, 2 per cent. 0 ; specific gravity '87 ; weight 8' 7 Ibs. per gallon.
Petroleum oil contains about 73 per cent. C, 27 per cent. H ; specific gravity '71 ; weight 7-10 Ibs. per gallon.
162 cubic feet of 16-candle gas will retain the vapour from 1 gallon carburine at 59° F., and 30 inches pressure. (Professor W. Foster.)
Where cannel is used for enrichment there is seldom much napthalene deposited.
To produce gas from iron and steam, for every 1,000 cubic feet hydrogen produced, rather less than 1 cwt. iron would be required- (H, Kendrick.)
BENZOL AS AN ENRICHER. 387
The "Browne" Process of Making, Lighting, and Heating Gas from Crude Petroleum.
An emulsion of 5 or 6 volumes of crude petroleum is made with 95 or 94 volumes of water. This emulsion is pumped slowly through a tube about 300 feet long under a pressure of 100 Ibs. on the square inch. One end of the tube is at the temperature of the air, the other is sufficiently hot to bring about chemical action between the vaporised contents, and hydrogen and carbon monoxide are liberated as permanent gases that are then passed through a coke-water scrubber and may afterwards be stored in a holder for use. The heat applied to the converting tube increases gradually from end to end. The light-giving value of the gas can be raised by allowing a greater proportion of petroleum to be added when about half-way through the converting tube.
Mixtures of ethylene and oxygen in insufficient quantity to form explosive mixtures possess greater illuminating power than pure ethylene, the highest luminosity observe:! being with 75 per csnt. ethylene and 25 per cent, oxygen. An increase of oxygen above this diminished the illuminating power.
Wood Gas.
One retort about 21 inches diameter by 9 feet G inches long will produce 12,000 cubic feet per day.
One ton of wood will produce 8.000 to 11,000 cubic feet-of 9 to 10- candle gas. Eesiduals, charcoal 4 cwt., tar 1^ cwt.
Benzene is as 500 to 900 candles per 5 cubic feet vapour, compared with napthalene. (Professor V. B. Lewes.)
Benzene is probably not efficient when the gas requires enriching more than 1 to 2 candles.
Benzene vapour should have an illuminating power of 700 candles per 5 cubic feet, with an enriching value of 3'9. (Professor V. B. Lewes.)
A gallon of benzol has an enrichment value of only 4,500 candles, and carburine is only one-fourth as effective. (Mr. W. Young, of Peebles.)
One gallon of benzol will enrich from 12,000 to 15,000 cubic feet, adding 1 candle-power to it. The cost to enrich 1,000 cubic feet to the extent of 1 candle-power with benzol is from £ tL to Id.
Four to 5 candles can be added to gas with GOO to 700 grammes benzol, and would be stable at 32° F. At 77° F. gas will hold four times the quantity of benzol which it will at 30° F. (Dr. Schilling.)
Temperature required to vaporise benzol = -4- 212° F.
It is unnecessary to heat benzol when using it as an enricher, except in very cold weather.
The molecular structure of the benzol molecule is such that, of all the liquid hydrocarbons known, it is the one which may be expected to break up most readily into that wonderful acetylene, which, according to some authorities, puts everything into the shade as a light pro- ducer. (T. Stenhouse.)
Vapour tension of benzene (90° benzol) at 59° F. equals 58'9 milli- metres,
C C 2
388 GAS ENGINEER'S POCKET-BOOK.
One gallon benzol will raise 24,500 cubic feet 16-candle gas 1 candle. (Dr. H. Bunte.)
Benzol boils at 177° F.
1,000 parts of water dissolve 1*45 parts of benzene, 0*57 parts of toluene, and 0'12 part of xylene.
Benzene can be obtained by keeping acetylene for a long time just below a red heat. (Professor Mills.)
From Manchester gas 3*5 gallons benzene per 10,000 cubic feet were obtained, 1882. (Wilfrid Irwin.)
From Manchester gas 3-7 to 4-25 gallons of liquid per 10,000 cubic feet were dissolved out, containing 80 per cent, hydrocarbons of the benzene series (1884), with an enrichment value of 4,500 candles per gallon. (G. E. Davis.)
At least three times the amount of petroleum spirit is required to repair the loss of a certain quantity of benzene, and there is also a great difficulty in getting the required amount into the gas without condensation. (Wilfrid Irwin.)
One cubic foot gas will permanently retain alone 50 grains benzol vapour at a temperature of 32° F. (T. Sten house.)
One gallon benzol will enrich 9,500 cubic feet gas 1 candle. (Hunt.)
One gallon petroleum spirit will enrich 2,800 cubic feet gas 1 candle. (Hunt.)
One gallon benzol will enrich 3,900 cubic feet gas 4 candles. (Schilling.)
One gallon benzol will enrich 8,500 cubic feet gas 1 candle.
One gallon benzol (90 per cent.) will enrich 13,800 cubic feet gas 1 candle.
One gallon benzol will enrich 20,000 cubic feet gas 1 candle. (J. F. Bell.)
One cubic foot benzol equals 40 candles (L. T. Wright).
„ „ ,,147 ,, (Professor Falkland).
„ „ ., 18 i „ (Knublauch).
The purity of the benzol is not stated in each case, hence the difference in results.
Benzene freezes at 32° F.,-and boils at 177° F. ; specific gravity at GO0 F. 0-8833.
Each grain absorbed per cubic foot of common gas increases illuminating power 10 per cent. (Letheby.)
|
Enrichment per Gallc Bunte giv Frankland , Hunt Knublauch . Stenhouse , L. T. Wright . W. Irwin 9» ' |
n per 10,000 Cubic Feet with Benzene. Candles Enrichment. es ... 3-6 |
|
2-9 . 0'9 . . 3-7 1-3 . 0-8 with flat flame burner 2*7 „ Argand „ . , 0'5 |
BENZOL AS AN ENRICHER. 389
To enrich with benzol, the coal gas is made to pass over the surface of cold benzol, and the vapour rising from this is taken up and com- bines with the gas at once, the quantity absorbed being regulated by the area of benzol surface exposed and the rate at which the gas passes through the benzoliser.
Gas enriched to 17 or 18 candles with benzene would be far better appreciated by the average consumer than 20-candle gas owing its illuminating power largely to olefmes.
Benzol will separate when the gas is exposed to great cold. (Dr. Buel.)
Commercial benzol if used for enrichment may contain sufficient sulphur to cause an increase of 10 grains S per 100 cubic feet of gas per 1 candle of enrichment.
Ninety per cent, benzol contains 25 per cent, toluol, therefore it is best to use the purest benzol for enriching, as the evaporation is not so rapid with toluol, nor the enriching value so great.
The higher the boiling-point of the paraffin series of hydrocarbons the greater is their enriching value. (Wilfrid Jrwin.)
While for carburetting feebly illuminating coal gas about 8'8 grains of benzol or toluol, or 31 -7 grains of pentane or hexane per candle per hour are required, with hydrogen double the quantity is required, and with carbonic oxide treble is required. (Dr. H. Bunte.)
Candle Cubic
Enrich- Feet of
ment. Gas.
1 gallon pure benzol = 1 per 13,300
1 „ commercial benzol = 1 „ 12,500
1 „ carburine (-689 specific gravity) . . . = 1 „ 5,700 1 ., common petroleum spirit (-700 specific gravity) = 1 „ 4,300
(T. Stenhouse.)
Gas will carry 3 per cent, benzol at 32° F. (Dr. Bunte.)
0*0033 gramme per litre per caudle enrichment is required with toluene.
0'003-t gramme per litre per candle enrichment is required with benzene.
0-0028 gramme per litre per candle enrichment is required with benzene and H.
0-0115 gramme per litre per candle enrichment is required with heptane.
0-0027 gramme per litre per candle enrichment is required with xylene.
0-0026 gramme per litre per candle enrichment is required with napthalene and H.
0'0020 gramme per litre per candle enrichment is required with napthalene.
0'0064 gramme per litre per caudle enrichment is required with phenol. (W. Irwin.)
390
GAS ENGINEER'S POCKET-BOOK.
To Test between Petroleum Benzene and Benzene from Coal Tar.
Use Syrian asphalte washed thoroughly with petroleum naptha to remove all constituents soluble. The colour of the mixture of the two benzenes after treatment with the asphalte varies from straw colour to dark brown according to the quantity of the coal tar benzene present, and these colours can be made to indicate the proportion of each benzene in the mixture. (Journal of the Society of Chemical Industry.')
Value of Acetylene as an Enricher of Coal Gas. (Professor V. B. Lewes.)
|
Composition of the Mixture. |
Illuminating Value. |
Enrichment Value of 1 Per Cent, in Candles. |
||
|
Coal Gas. |
Acetylene. |
Coal Gas. |
Mixture. |
|
|
99-10 |
0-90 |
13 |
13-9 |
1-0') |
|
97-90 |
2-10 |
13 |
15-1 |
i-oo |
|
96-00 |
4-00 |
13 |
17-3 |
1-07 |
|
95-20 |
4-80 |
13 |
18-4 |
•12 |
|
91-00 |
9-00 |
13 |
23-5 |
•16 |
|
89-50 |
10-50 |
13 |
25-3 |
•17 |
|
85-00 |
15-00 |
13 |
33-0 |
•33 |
|
83-25 |
16-75 |
13 |
36-1 |
•36 |
|
66-90 |
33-10 |
13 |
60-5 |
•43 |
|
55-50 |
44-50 |
13 |
76-7 |
•43 |
|
16-70 |
83-30 |
13 |
175-2 |
1-94 |
|
oo-oo . |
100-00 |
0 |
240-0 |
2-40 |
The theoretical yield of acetylene is 25 Ibs. per 60 Ibs. of carbide approximate — more correctly, 26 Ibs. to 64 Ibs.
The following data for a 1,000 horse-power engine arc based on the estimates of D. Adolph Frank, of Charlottenbcrg, and are intended to show the saving in space obtained. The engine is supposed to be run for 600 hours, and at T54 Ib. of coal per horse-power per hour would require about 420 tons, which would occupy about as many cubic metres. Liquid acetylene at 39 Ibs. per horse-power per hour would weigh about 108 tons, and occupy about 300 cubic metres, while carbide of calcium with 36 per cent, by weight of acetylene, need not occupy much more than 150 cubic metres, even after allowing for protective apparatus. In the latter cases the space occupied at present by the boilers would not be required.
Acetylene with different proportions of air gives the following results : When 1,000 cubic inches of the mixture contain less than 77 cubic inches of acetylene, it will burn completely, producing water and carbon dioxide. When the proportion of acetylene is increased so that it forms from 77 to 174 cubic inches per 1.000 of the mixture, the product consists of water, carbon dioxide, carbon
ACETYLENE.
391
monoxide and hydrogen, and the combustion is therefore imperfect. With larger proportions of acetylene free carbon and unaltered acetylene are left. When anything between 28 and 650 cubic inches of acetylene are present in 1.000 of the mixture it will take fire. (M. Le Chatelier.)
Calcium carbide, CaC2 + H20 = C2H2 + CaO.
1 Ib. CaC2 makes about G cubic feet acetylene (C^H^) of about 48 candle-power per foot.
10 volumes water will absorb 11 volumes acetylene gas at ordinary temperature and pressure.
Iron burners are not suitable for use with acetylene gas, as the gas destroys the metal and enlarges the holes.
Gas is evolved from calcic carbide until a pressure of 1,100 Ibs. per square inch is present.
87j Ibs. lime to 56^ Ibs. C vield 100 Ibs. calcium carbide and 43| Ibs. CO.
100 Ibs. carbide yields 40'62 Ibs. acetylene and 115-62 Ibs. slaked lime, or 5 '9 cubic feet of acetylene per Ib. carbide.
Calcic carbide has specific gravity 2'262.
„ „ is liquefied at 32° F. by a pressure of 21 i atmospheres.
1 Ib. liquefied calcic carbide will expand to 14 J cubic feet at atmospheric pressure.
Space required in generator 80 cubic inches per 1 Ib. carbide.
1 volume acetylene -4- H volumes air is slightly explosive.
1 » » • +12 »> » very " „
1 „ + 20 „ •„ not
Acetylene or ethine (C2H2) is colourless, and burns with an intensely luminous flame, of the odour of rotten vegetables. Is made by the action of H20 upon calcium carbide (CaCs), the latter the produce of carbon and calcium burnt in an electrical furnace.
Acetylene has approximately 15 times the lighting value of common gas, but has only two and a half times the heating value.
When acetylene is subjected to a pressure of 22 atmospheres at 0° C. it is condensed to a colourless mobile liquid lighter than water.
The Toxicity of Acetylene.— M. Grehant found it is poisonous if inhaled in large quantities between 40 and 79 per cent.
The amount of acetylene in Manchester gas never exceeds 0'05 per cent.
6-35 cubic feet C2H2 gives 1 H.P.
Specific gravity C2H2= O'Dl.
Comparison of Illuminating Value to Proportions of Acetylene. (Professor V. B. Lewes.)
|
Analysis of Mixture. |
Acetylene at Top of Non-luminous Zone. |
Illuminating Value of Flame per 5 Cubic Feet. |
|
|
H. |
Acetylene. |
||
|
65-5 43-5 o-o |
34-5 56-5 100-0 |
3-72 8-42 14-95 |
14-0 87-0 240-0 |
392
GAS ENGINEER'S POCKET-BOOK.
Purified Lowe oil gas contains :—
H 22-f>
Saturated hydrocarbons, methane, &c. . . 31 '9
., carbon, cthylene, £c. . . . 13-4
CO 29-2
() 0-6
N 2-3
100-0 (Professor Lewes, 1893.)
H
CO C03
N .
Average Composition of Water Gas (Non-luminous). (Professor Lewes.)
48-31 per cent. 3.-> -93 „ 4-25 „
8-75
Methane . 1*05 per cent. H.,S . . 1-20
o o-r.i
Analysis of Water Gas. (Ltinctf).
Hydrogen (H) Methane (CH4) . Carbon monoxide (CO) . Carbonic acid (CO.,) . Nitrogen (N) .
PerCent. l>y. Volume. . 49-17 . 0-31 . 43-75 . 2-71 4-06
S candle-power water gas consists of : —
Per Cent, by Volume.
Hydrogen 34
Methane 15
Hydrocarbons absorbable by fuming sulphuric acid . 12'5
CO 33
Nitrogen from 0-5 to 5
Specific gravity equals 0'02 (air 1). (Butterfield.)
Analysis of Carburetted Water Gas at Outlet of Exhausters.
C02 . CO .
CnH.,11
4-6
14-8
21-2
30-7
18-4
1-0
9-3
100-0
CARBTJRETTED WATER GAS PLANT. 393
Generator of ^ million plant, generally 18 feet high, 10 feet diameter, with fire bars 4: feet from bottom, with 4 cleaning doors 8 feet from bottom, the upper portion coned to an opening about 2 feet diameter.
Carburettor same size, but no doors, filled with checker bricks.
Superheater 24 feet high, 10 feet diameter, also filled with checker bricks up to within 4 feet from top.
Scrubber, 20 feet high, 6 feet diameter, filled with layers of wood strips placed check erwise.
Condenser. 20 feet high, 0 feet diameter, filled with 2-inch tubes.
The generator, carburettor, and superheater are usually lined with fire-clay blocks 10 inches thick, with space of 2 inches between shells and bricks, tightly packed with a non-conductor. The blast inlet to the generator is below the fire bars, where the steam is also admitted. The blast inlet to the carburettor is at the top, and to the superheater at the bottom.
Superheater usually 6 to 8 feet higher than the carburettor.
Maximum pressure in shells, ordinary working, 40 inches water.
Average ., „ ., " 30 „ „
Pressure at which shells should be gas tight, 3 Ibs. per square inch.
Pressure of air blast. 12 to 15 inches of water.
Pressure of steam, 130 Ibs. per square inch.
Blast mains usually No. 18 Birmingham wire gauge galvanized iron ; average blast 14 inches water.
Blowers usually work 2,000 revolutions per minute.
Temperature in generator should not be allowed to get below 1,000° C., and fuel of sufficient depth to convert the C02 to CO, provided, and the C should be in excess. Best temperature, about 1,100° C.
Superheater must be kept at a temperature just below that required to separate the C from the oil vapours.
Gradually increasing heats in carburettor and superheater best for fixing oil gas. Oil injected at from 25 to 30 Ibs. per square inch.
Too low heats give a tarry stain on white paper held to pet cock on superheater.
Too high heats give a deposit of carbon particles on white paper held to pet cock on superheater.
Coke for feeding generators should be of even size and screened, giving little ash so that the steam may not pass through the fuel too freely. Coke must be fed regularly, say every two hours.
Superheated steam obtained by use of boilers working at 130 Ibs. pressure.
Blast pipes are often made of 16 Birmingham wire gauge, and are all connected by small pipes, so that the pressure is in all even when the fans are not running in every set.
Two-inch safety tube is fixed just outside blast valve, so that if oil is leaking back through blast stop-valves on vessels the pressure causes a smoke to issue from the tube.
One foreman superintends the work of gas making and clinkering.
A gang of four men clinker three fires twice during eight-hour shift.
394
A safety valve is fixed outside each blast inlet valve of the same bore as the pipe.
Seal in seal pot, 3 inches.
Tubes in condenser which comes after the scrubber, 1£ inches diameter.
In lighting up, fill up generator with coke and open the stack valve, shut generator charging door and turn on blast at generator ; when the brickwork of carburettor is red hot turn on blast there until superheater is red hot, and then put blast there until all are cherry red hot.
If coke is required in generator before all are hot, shut all blast off and close stack valve, and then open charging door.
In working, shut off blast first from generator, then carburettor, and then superheater, shut stack valve, then open oil feeder, and next turn on steam to generator and oil pumps.
When gas making is finished, shut off oil, then steam to generator, open stack valve, and then open blast on superheater, carburettor, and generator.
Average fuel required per 1,000 cubic feet gas made, 45 Ibs.
Average oil required per 1,000 cubic feet gas made (distillate from Russian crude), 5-46.
Candle power per gallon oil developed, 9'03.
Percentage volume C02 in crude gas, 4 per cent, by volume.
Illuminating power of gas, 24*68 candles.
Low heats or excess steam produce increase of C03.
Half million per day plant can be started in full working order in 3J hours.
Temperature at which C decomposes water vapour to CO-2 and 2 H2 equals 600° C.
Temperature at which C decomposes water vapour to CO and H2 equals 1,000° C.
When steam superheated, or at. say, 130 Ibs. per square inch, is passed through fuel at 1,000° C., CO -f- H2 are formed with about 3 per cent. C02.
To avoid explosions when lighting up, fill the generator to the top with fuel under slow fire without blast, and when blast is put on do not open the generator until it is at a working heat.
Checker work requires renewing every six months (about) and should have superficial area of 16 square feet per 1,000 cubic feet made per diem, not including linings.
By superheating, a considerable increase of illuminating power can be obtained with either crude petroleum (naptha) or pure paraffins. (Dr. H. Bunte.)
The quantity of water gas produced from 1 Ib. of carbon is about 61 cubic feet at 600° F., and to produce this 4,200 heat units are absorbed, or about 70 units per cubic foot.
With carburetced water gas on a commercial scale 1,000 cubic feet of 22-candle gas can be produced from 50 Ibs. coke and 4 gallons oil.
Mix rich gases with poor ones as early as possible during manu- facture.
ANALYSES OF CARBURETTER WATER GAS.
395
C02 CO
o
JST
Minutes C02 .
Analysis of Heating Gases at—
Outlet of Outlet of
Producer. Superheater.
7-94: . . 15-10
. . . . 23-21 . . . 0-10
." . . . — . . 3-80
68-85 . , . 81-00
Proportions of C02 per Minute of Bun. 1234 5
. 0-5 1-7 4-1 G-2 7-9
Average. 4-05
Percentage of C0.3 at End of Each Minute of a Five Minutes' Hun, at Outlet of Generator. (Butterfield.) 1st minute = 0'3 per cent. C0$ 2nd „ = 0-6 3rd „ = 1-4 4th „ = 2-6 „ 5th == 4-2
Average 1 -82
Proportion of C02 increases according to length of run.
C02 in water gas varies from 1^ to 4 per cent.
Only 3 per cent. C03 should be present in water gas, as it reduces the illuminating power of the gas.
Percentage of C02 in uncarburetted water gas usually 4 to 5 per cent.
CS2 in carburetted water gas is about 4 grains.
CO in crude carburetted water gas at Blackburn equals 28 or 29 per cent.
Analysis of Crude Carburetted Water Gas. (Paddon and Goulden.)
(Class of oil used, a rough distillate from Russian crude.) H . 21-8 H2S and CO-2
CH4 .
CnH2N CO
30-7 12-9
28-1
3-8 0-5 2-2
At Blackburn, the total of five experimental runs with water gas (carburetted), 17,560,000 cubic feet gas of 22-77 illuminating power was made from 57,992 gallons "solar distillate" -875 specific gravity. 648.267 Ibs. coke was used, and 1,162,000 gallons water.
C02 CO H N
Analysis of Water Gas.
American Practice.
3-5
. . 43-4 . 51-8 1-3 .
English Practice.
396
GAS ENGINEER S POCKET-BOOK*
Carburetted water gas from coke should contain about 3 per cent C02.
Carburetted water gas from coke should contain about 2 per cent. H2S.
Sulphur compounds not exceeding 10 grains per 100 cubic feet.
Cost of purifying Carburetted water gas equals I'Oi'Sd. per 1,000 cubic feet.
Carburetted water gas making requires only half the labour of coal gas, and saves -lid. per 1,000 cubic feet for purification.
Water gas can be enriched at the rate of 0-006 gramme per litre per candle.
26-candle Carburetted water gas contains 60 per cent, by volume of pure water gas.
26-candle gas is the most economical to make.
Enriching value of 20 to 25 candle-power water gas (carburetted) equals about 20 per cent, more than its nominal value. (J. Methven.)
Water gas per se has not any illuminating power.
Solar distillate has specific gravity about '875 of flashing point 170° F.
Solid residue from oil should not exceed 2 per cent, by weight.
Water required for condensing carburetted water gas equals 90 gallons per 1,000 cubic feet. (A. G. Glasgow, 1802.)
Approximate Analysis of Oil Gas Tar, from Condensers.
(Paddon and Goulden.) Special gravity of Tar -996.
|
Per Cent, by Volume. |
Per Cent, by Volume Without Water. |
|
|
Water |
76-5 |
|
|
Benzene |
0-28 |
1-19 |
|
Toluol |
0-90 |
3-83 |
|
Light paraffins, &c. . . Solvent naptha (zyloete) |
2-0 4-15 |
8-51 17-96 |
|
Phenol |
only a trace |
only a trace |
|
Middle oils (naptha, &c.) |
6-92 |
29-4 1 |
|
Creosote oil and green oil . . |
5-70 |
21-26 |
|
Napthalene .... |
0-30 |
1-28 per cent, by |
|
weight |
||
|
Anthracene cake . . |
0'22 contains |
0-93 |
|
8-33 per cent. |
||
|
anthracene |
||
|
Coke |
2-30 |
9-80 |
|
99-27 |
97-20 |
|
|
Loss . ... |
0-73 |
2-80 |
|
100-00 |
100-00 |
CARBURETTED WATER GAS TAR. 397
Carburetted water gas tar contains about 70 per cent, water as it leaves the apparatus.
Water used for cooling and scrubbing about 70 gallons per 1,000 cubic feet gas made, but this quantity is being reduced in mcdern plants to about 40 gallons.
In America the production of oil gas tar by the Lowe process is about 12£ per cent, of the oil used.
To adequately protect petroleum tanks from lightning, it is neces- sary that all openings through which vapour can escape should be guarded with wire netting upon the principle of the Davy safety lamp. (Professor Neesen.)
Joints in pipes for petroleum carrying should, preferably, be screwed, and when all oil has been removed from the threads, a good thick shellac varnish should be applied to the outside and inside threads.
Yellow soap, treacle, honey, glue, mucilage, or glycerine are all quite petroleum proof. Canvas saturated with shellac varnish makes a good washer and might be used as the strip in riveted joints.
Analysis of Belfast Carburetted Water Gas.
C02 . •>'; ;: .' . . nil.
0 nil.
Unsaturated hydrocarbons . . 10- 7 per cent.
CO . . / . . ' . . 31-9 „
Saturated hydrocarbons . . . 16'2 .,
H 33-7 '.,
N 7-5 „
100-0 „
C02 in crude gas . 3-5 per cent.
SH2 „ „ ;;;., ;ri<£; . -2 „
In water gas plant, at end of first minute gas should contain 0'3 per cent. C02 ; at end of second minute gas should contain 0'6 per cent. C02 ; at end of third minute gas should contain l-4 per cent. C02 ; at end of fourth minute gas should contain 2*6 per cent C02 ; at end of fifth minute gas should contain 4*2 per cent. C02. (Butterfield.)
Crude water gas from coke (carburetted) will contain about 90 to 150 grains H2S per 100 cubic feet, and about 3 per cent. C02, no ammonia, sulphur compounds not more than 10 grains per 100 cubic feet. Purification of water gas from C02 is twice that of coal gas. (Butterfield.)
If air is forced through red hot coke, 1 Ib. of carbon in burning to CO liberates 4,451'4 units of heat ; but if burnt to carbon anhydride, 14,544 units.
If there be sufficient body of carbon for this latter gas to pass through, it is decomposed with the absorption of 10,000 units of heat.
398 GAS ENGINEER'S POCKET-BOOK.
One pound C requires 1£ Ibs. O, and forms 2j Ibs. CO, but air would contain for 1^ Ibs. 0 about 4J Ibs. N.
If steam is forced through 1 Ib. C requires H Ibs. steam to form CO. and this steam contains 1^ Ibs. 0 and £ Ib. H.
One pound H burnt to water, yields 62,500 heat units, this -f- 6 = 10,416 heat units equal to quantity absorbed by the hydrogen ; and less 1,723 heat units (the heat already absorbed by the steam) equals 8,693 units, of which 4,500 will be supplied by the forming of CO, leaving 4,200 units to come from the previously heated coke.
In practice more is taken from the coke, as the gases escape hot. (Norton H. Humphreys.)
Steam brought into contact with an excess of carbon at 1,000° F. is decomposed into its component gases H and 0, and combines with the carbon to form CO -j- H.
Equation of water gas production —
First action . 4 (H20) + 2 C = 2 C02 + 8 H. Second action . 2 C03 + 8H + 2C = 4CO + SH.
(B. H. Thwaite.)
The 0 of steam attacks not only the surplus carbon, but also the hydrocarbon when mutually decomposing, as in water gas plants, bringing about the destruction of a large quantity of illuminating matter. (Young.)
Ordinary producer gas contains about 30 per cent, by volume of combustible gases, and has a calorific value of about £th that of 16- candle gas.
If producer and water gas were mixed the mixture would consist of 30-5 H, 60 CO, and 60 N.
Minimum temperature for formation of pure water gas, 1.800° F.
To form sufficient heat for the production of 1 volume water gas 1-4 volumes producer gas are required.
Temperature in water gas generator should never be lower than 1,000° C., and fuel should be of sufficient thickness to ensure as complete a conversion of the C02 to CO as possible.
With hard anthracite coal it is possible to so arrange the tempera- ture in the generator that practically no C02 is formed, but with coke a percentage of the product is almost bound to be produced. H2S is also absent when anthracite is used, as it is formed from the S in the coke.
Carburetted water gas plant at Blackburn —
Coke used per 1,000 cubic feet 30'8 Ibs. for generator. „ ., „ „ 6-1 „ „ boiler.
„* „ „ „ 36-9 total.
Oil, candles per gallon . . 6'97 Oil, specific gravity . . . '878
Mr. Foulis found that with ordinary water gas apparatus he re- quired 30 Ibs. to 40 Ibs, coke per 1,000 cubic feet of 30-candle gas using 6 gallons oil,
CALORIFIC VALUE OF WATER GAS. 399
Uncarburetted water gas has only about half the calorific power of coal gas, but when carburetted to about 22 to 23 candles is about 85 per cent, to 95 per cent, the power.
Semi water gas contains from 80 to 85 per cent, of the heating value of coal, and is the cheapest gas if supplied within a reasonable distance from the place of production. (A. Kitson.)
Water gas from anthracite coal has a calorific value of 290 heat units. Water gas from bituminous coal has a calorific value of 350 heat units. (B. Loomis.)
Difference in heating value of carburetted water gas and coal gas is ns 9 to 10.
Water gas, hydrogen, or mixtures of the two, when carburetted by the vapours obtained by decomposing hydrocarbons yield a flame which, although it may be of high illuminating value, is far shorter and smaller than the flame obtained from ordinary coal gas, and that in consequence of this it has to be burnt in larger quantities in order to obtain a flame which shall in appearance equal that of coal gas. This is due to the coal gas containing from 36 to 4(5 per cent, of methane, or light carburetted hydrogen, which gives body and length to the flame, and which only exists in carburetted water gas or hydrogen to the extent of from about 16 to 26 per cent. (Professor V. B. Lewes.)
Carburetted water gas gives a small flame and lower durability than coal gas of equal illuminating power.
Coal gas carburetted by petroleum gives larger flame and higher durability.
The enriching value of 33-candle carburetted water gas is from 6 to 8 per cent, higher, and 47-candle carburetted water gas is 10 per cent, higher than when tested alone in the photometer. (A. Wilson.)
Messrs. Frankland and Wright, and Dr. J. Louttit found by experiments with young rabbits that the effects of carbonic oxide were not more poisonous than ordinary coal gas.
Approximate Cost of Water Gas per 1,000 Cubic Feet at 25 Candles.
s. d.
Oil, 4 gallons at 3*r7
45 Ibs. coke for generator, and 12 Ibs. for steam, ) equal to 57 Ibs. at 12*. Gd. per ton . . f
Labour .
Purification
Wear and tear
By the Van Steenbergh process 30 Ibs. to 40 Ibs. foundry coke are required per 1000 cubic feet gas made and carburetted with from 3 to 3£ gallons naptha. Illuminating power equal to 22 candles ; loss of illuminating power by storage in cold weather, 2 candles. CO equal to 15 to 20 per cent.
400
GAS ENGINEERS rOCKET-BOOK,
Composition and Illuminating Power of Gas from Van Steenbergh Process, with Different Fuels and 76° Naptha. (V. B. Lewes.)
|
Gas Coke. |
Anthracite. |
||||
|
Foundry |
|||||
|
Coke. |
Unpuri- fied. |
Purified. |
Unpuri- tied. |
Purified. |
|
|
H . |
33-44 |
|
39-05 |
_ |
38-44 |
|
Marsh gas . . . |
23-38 |
— |
26-71 |
— |
19-30 |
|
llluminants |
11-14 |
— . |
9-27 |
— |
7-49 |
|
CO . |
19-00 |
|
13-50 |
|
23-81 |
|
C02 . . . |
2-24 |
G'Ol |
1-02 |
2-10 |
0-42 |
|
N .... |
9-50 |
. |
9-72 |
|
9-69 |
|
0 . |
1-30 |
|
0-73 |
|
0-85 |
|
H2S . |
nil |
0-35 |
nil |
trace |
nil |
|
Illuminating power |
) 22-4 |
22-9 |
21.8 |
||
|
corrected |
) candles |
— |
candles |
— |
candles |
Manufacture of Dowson Producer Gas.
Superheated steam and air are passed through a generator con- taining a good body of incandescent fuel (preferably anthracite coal, but coke will do), the air supporting combustion ; the steam is decomposed, the 0 combining with the C of the fuel, first making C02, but on passing through the remainder of the hot fuel is reduced to CO, which is necessary to ensure that it has a sufficient affinity for 0 to explosively combine with the 0 of the air in the gas engine cylinders, while it must be remembered that each molecule of C02 makes two of CO. The gases are led through coolers and condensers when they are ready for use. 10 Ibs. of anthracite yield about 1.000 cubic feet of gas, but to this must be added 2 Ibs. of coke, required for the steam boiler.
With Dowson gas 1 Ib. of fuel per I.H.P., or 1} Ibs. per break horse-power can be attained in a gas engine.
Dowson gas is about equal to coal gas at !.<?. 6^7. per 1,000 cubic feet, as about four or five times the quantity is required, and larger engines are necessary.
One pound steam per 1 Ib. Welsh anthracite is usually allowed in Dowson gas. The producer must be kept hot, or tarry matters will be deposited.
Dowson water gas has about one fourth or one fifth the explosive force of coal gas, but requires for its production only 14 Ibs. of anthracite coal per 1,000 cubic feet.
Dowson producer gas contains from 45 to 48 per cent. N.
Siemens producer gas generally contains 60 to 70 per cent. N", which renders rapid ignition difficult.
FUEL GAS. 401
Heating value of Dowson gas, 150 British thermal units per cubic foot. Air required for complete combustion of Dowson gas equals 1 to 1, to 1£ to 1, by volume of the gas. With Dowson gas the products of combustion must be expelled.
In the Dowson producer 1 Ib. of steam is required per pound of anthracite.
Dowson gas requires one and a half volumes of atmospheric air per volume of the gas for complete combustion.
The initial pressure in gas engines is more than double that usually adopted in steam engines, and this gives the gas engine an advantage.
A steam engine cannot convert into work more than 30 per cent, of the heat energy. A hot-air engine cannot convert into work more than 50 per cent, of the heat energy. An internally fired gas engine cannot convert into work more than 80 per cent, of the heat energy. (Professor Kennedy.)
Coke for use in Dowson producers should be clean (not mixed with small coal or yard sweepings) and in pieces about 1 inch to 1^ inches cube.
About 80 cubic feet Dowson gas made from coke are required per I. H". P. per hour.
Gasholder required for Dowson gas for 100 I. H. P. plant is 8 feet diameter X 8 feet deep ; contents 400 cubic feet.
Dowson gas has about one-fourth the explosive force of ordinary coal gas.
The generator gas contains a large proportion of nitrogen and some C02.
CO does not ignite as rapidly as H.
It is necessary to use a higher compression for a charge of generator gas than for ordinary town gas, so as to bring the molecules together,
The volume of exhaust steam and products of combustion in a steam power plant is reduced 90 per cent, when gas power is used.
If coal gas be subjected to sudden and severe refrigeration it will part with some of its valuable hydrocarbons, and this to a greater extent if the gas be stagnant.
Nineteen to twenty candle gas, which has been purified by 2J per cent, air, does not lose any appreciable quantity of illuminating power during a travel of eight or nine miles through the town mains.
Fuel Gas.
Semi-water gas contains from 80 to 85 per cent, of the heating value of coal, and is the cheapest gas if supplied within a reasonable distance from the place of production.
The producer consists essentially of a cylindrical shell of boiler- plate lined with fire brick. The internal diameter of the brick- work is 21 inches and the height from the grate to the top of the furnace isJH feet. The grate is connected at one side with a steam and air injector, and on the- other side with a gas supply-pipe. It is surrounded by a cast iron ashpft. A small reservoir or boiler is placed at one side, connected with which are two coils contained in tf.£. D D
402 GAS ENGINEER'S POCKET-BOOK.
the brickwork, the lower of which supplies steam and the upper one of which superheats it. Air channels are formed in the brickwork, arranged spirally, through which air is drawn by the injector and heated before mixing with the steam. The grate is provided with mechanism giving it a rotary and up-and-down movement to break up clinker or caking soft-coal. Five hundred cubic feet of gas per hour can be produced from G Ibs. or 7 Ibs. of coal. (A. Kitson.)
Peebles Process.
The retorts used in the Peebles process yield 500 cubic feet of gas per hour, and 5J cwts. (per ton of oil decomposed) of hard graphite coke.
Heat required for fresh oil in Peebles process retorts equals 1,100 to 1,200° F. For condensible products, 1,400 F.
Oil of -850 specific gravity gave 5 cwt. coke per ton at Perth.
Enriching value of Peebles oil gas is 50 per cent, higher than the illuminating power when burnt alone. (S. Glover.)
Peebles oil gas used as an enricher has prevented the stoppage of services with napthalene during the most severe winter.
One ton of tar from Durham coal by the Peebles process yields 15,000 cubic feet of 25 candle gas, and 15 cwt. coke of good quality. (Bell.)
Dr. Stevenson Macadam stated (1887) that he considered 6,885 Ibs. of sperm light as the theoretic value of the gas from 1 ton of oil.
He found mixing oil, gas, and air entailed a loss of illuminating power ; after making all allowance for the admixture, he advocated the use of water gas as a diluent for oil gas.
To gasify tar permanently about 2,000° F. is required.
It has been suggested when supply of gas is short to mix about 2 gallons of tar per charge with the coals, and thus keep up the illuminating power.
Gases passed over Gasolene at 50° F. will completely evaporate it, giving air an illuminating power of 60 candles, and poor gas an illuminating power of 80 candles.
No condensation has been found in the syphon boxes in the district in Rochdale, when carburine has been used as an enricher.
It is best when enriching with a cold process to put the enriching apparatus on the delivery pipe from the works.
One Gallon Carburine (specific gravity 0-680) will raise 8,000 cubic feet 1 candle.
Yield of Gas in Pintsch System equals 81 to 83 cubic feet per gallon of 51 candles ; compression to 150 Ibs. per square inch, reduces illuminat- ing power to 38 candles, and deposits one gallon hydrocarbon per 1,000 cubic feet. (J. Tomlinson.)
Cost of fitting gas to railway carriages (Pintsch or Pope systems) equals about £5 per lamp, including its proportion of reservoirs, pipes, gauges, &c. Cost of working about T20ths of a penny per lam]) per hour equals about one-half that of oil. Maintenance costs about 2s. per lamp per year.
COMPKESSING COAL GAS,
403
Loss in Volume of Coal Gas when Compressed. (C. E. Botley.) Illuminating power of gas IG'^O candles.
|
Pressure. |
Volume. |
Loss. |
|||
|
Lbs. per Square Inch. |
Atmo- spheres. |
Gas put into Cylinder. |
Gas used per Meter. |
Cubic Feet. |
Per Cent. |
|
45 |
8 |
510 |
510 |
nil. |
nil. |
|
75 |
5 |
850 |
800 |
10 |
1-16 |
|
105 |
7 |
1,190 |
1,205 |
15 |
1-24 |
|
135 |
9 |
1,530 |
1,570 |
40 |
2-54 |
|
1G5 |
11 |
1,870 |
1,920 |
50 |
2-(50 |
|
195 |
13 |
2,210 |
2,330 |
120 |
5-15 |
|
200 |
13J |
2,267 |
2,450 |
183 |
7-47 |
n D 2
404 GAS ENGINEER'S POCKET-BOOK.
PRODUCTS WORKS.
Chimneys in chemical works should be at least 250 feet high.
The simplest form of sulphate plant is a boiler in which the liquor is heated, and from which a pipe to convey the vapours is carried to the sulphuric acid in the saturator where sulphate crystals are formed. The addition of lime or caustic soda to the liquor in the boiler causes the ammonia, combined with other gases which are in the liquid, to pass off as gas, and consequently be converted into sulphate.
Seventeen parts pure ammonia combine with 49 parts pure sulphuric acid to form 63 parts sulphate of ammonia (2 (NHJ SOJ.
Reaction of Ammoniacal Liquor and Sulphuric Acid, 2 NH3 + Ha SO, = 2 (NHJ S04.
The volatilization of the ammonia from gas liquor in all modern plant is effected by means of continuous working stills, viz.. distilling a regular stream of liquor as it flows by its own gravity through the intricacies of a still heated by direct steam.
To calculate amount of Sulphate of Ammonium to be obtained from Liquor.
Ounce strength X 1'347 X gallons of liquor equals ounces weight of sulphate; or, ounce strength X '0841 equals Ibs. sulphate per gallon.
2,000 gallons of S-ounce liquor will produce 15 cwt. sulphate, requiring also 13£ cwt. of sulphuric acid, or, say, 1 ton sulphate per 100 tons of coal in small works.
One per cent. N in coal equals 105 Ibs. ammonium sulphate (pure). (Butterneld.)
Coal may be said to contain 1| per cent. N equal to 140 Ibs. sulphate of ammonia per ton ; it is not usual to obtain more than 27 or 28 Ibs. sulphate.
In sulphate plant it is necessary that the condensers and purifiers be of ample capacity.
Mr. Croll proposed to make sulphate of ammonia by passing the products of combustion from a coke furnace through a "coffey " still containing ammoniacal liquor, and then precipitating the sulphate in the usual saturator. He thus obtained an increase of sulphate per gallon of acid, and greatly lessened the quantity of HaS given oif.
Of the 1'7 per cent, of N in the coal, only about -25 per cent, appears as ammonia after carbonization. Some coals contain as much as 2 per cent. N. If all the N were converted into NHS. sulphate would equal 215 Ibs. per tori of coal. About 50 per cent, of the N remains in the coke. About '027 per cent, of the N in the coal forms in the
SULPHATE MANUFACTURE. 405
purifiers calcium cyanide and calcium cyanate. If steam, water gas or hydrogen were passed through heated coke, a large proportion of the N could be removed, and afterwards converted, and with that already evolved with the gas a make of about 1 cwt. of sulphate per ton could be obtained.
One ton sulphate equals about 5 cwt. NH.3
One ton 10-ounce liquor equals about 51 Ibs. NH3 equals 2£ per cent.
One ton sulphate equals 11 tons 10-ounce liquor.
One ton coal produces 35 to 40 gallons 10-ounce liquor equal to 30 to 35 Ibs. sulphate.
7,000 gallons liquor require —
Yield as Compared
with Theory. Hours. Per Cent.
When heated by open fire from without . . 22 . 90'0 When heated by a steam coil (indirect steam) .18 . 92-0 When open steam is blown in . . . . 14 98-5
(Dr. Lunge.)
The liquor in the saturator should be kept about 54° Twaddell.
Efficient sulphate plant requires about 8 cwt. fuel per ton sulphate made.
Temperature in sulphate well equals 75°, after passing jet elevator 116°.
In the economiser 180°. (S. Ellery.) •
The waste gases from the saturator have usually a temperature of 186° F., and bv utilizing these the liquor can be raised to about
According to the reports of the Chief Inspector under the Alkali Works Regulation Act, the make of sulphate of ammonia was —
For 1894. Tons.
In Gasworks . . . . . . . 110,748
„ Ironworks ....... 11,000
„ Shaleworks ...... 23,105
„ Coke and Carbonizing Works . . . 4,973
Totals . . 149,82(>
To manufacture sulphuric acid, burn S, and pass with peroxide of nitrogen, air and steam, in regulated quantities to a large chamber, where H2S04 condenses, and is of sufficient strength for the manu- facture of sulphate (equation 2 S02 + N04 + 2 H20 = 2 H2S04 4- N02).
Sulphate of ammonia contains 20 per cent, of nitrogen, and nitrate of soda only 15 per cent. Three-quarters of a ton of sulphate has in it as much food for a crop as a ton of nitrate. Of course it is true that the nitrogen in the nitrate is accepted as being more effective than the nitrogen in the sulphate, but the outside difference in manurial power is certainly not more than 10 per cent.
406
GAS ENGINEER'S POCKET-BOOK.
When it is also remembered that the more concentrated nature of sulphate means a saving of 25 per cent, on the carriage, and that it can often be bought at still lower rates from local gasworks, it is clear that for any other than very light sandy soils, sulphate rather than nitrate should be bought at present.
Professor Somerville states that sulphate of ammonia and nitrate of soda are nearly of equal value per unit of nitrogen as manures, therefore 861bs. sulphate equals 112 Ibs. nitrate.
Sulphate of ammonia has proved itself a better nitrogenous manure for mangolds than nitrate of soda.
One-eighth cwt. sulphate of ammonia per acre on hay land is the best dressing ; or f cwt. sulphate equals 1 cwt. nitrate of soda.
Preliminary nitrification of sulphate of ammonia is not necessary when using the latter as a manure.
From Coal Tar are obtained by distillation the following valuable bodies : benzene, toluene, naptha, carbolic acid, creosote, anthracene, napthalene, and a residue of pitch. The benzene and toluene yield aniline whence the dyes magenta and methyl violet are obtained ; the phenol and creosote form the basis of valuable antiseptic and dis- infectant preparations, and the first-named is also the source of the dye aurine ; naptha is valuable chiefly as a rubber solvent ; naptha- lene yields napthylamine, abeta-napthol, vermillene. scarlet, and napthol yellow ; anthracene gives on treatment alizarin, from which a great number of beautiful dyes are prepared. By itself, also, coal tar has many applications, as, for instance, for making gas as fuel, and as a preservative for building materials. Then should be mentioned the legion of coal tar derivatives : antipyrin. antifebrin, analgen, exalginek salol, saccharin, and salicylic acid. (Lancet.)
Constituents of Coal Tar.
|
Average |
Weight Per |
Proportionate Weight of Constituents. |
Calorific Value. |
|||
|
Cent. |
C. |
H. |
C. |
H. |
||
|
Units. |
Units. |
|||||
|
First runnings |
C5H10 |
3 |
•025714 |
•004286 |
200 |
148 |
|
Light oil . . |
CS^M |
7 |
•Ofi 1091 |
•008910 |
474 |
307 |
|
Middle oils . |
CiaHao |
27 |
•237073 |
•032927 |
1,842 |
1.145 |
|
Heavy oils . . |
C^HIC |
7 |
•063913 |
•006087 |
497 |
210 |
|
Pitch (56 per |
||||||
|
cent.) com- |
||||||
|
posed of Oils |
Cir,H10 |
17-5 |
•166336 |
•008663 |
1.292 |
298 |
|
Carbon . . . |
c |
27-5 |
•275000 |
— |
2,137 |
|
|
Gases and |
||||||
|
Water (H, |
||||||
|
NH3). . . |
— |
11 |
||||
|
•829127 |
•060873 |
6,442 |
2.108 |
|||
|
lotai .... |
0-89 |
8,550 |
ANALYSES OF TAR.
407
The number of constituents taken was : First runnings, 17 ; light oil, 26 ; middle oils, 5 ; heavy oils, 15 ; and pitch oils, 4.
The boiling points were respectively : Up to 110° C. ; 1 10° to 210° C. ; 210° to 240° C. ; 240° to 270° C. and upwards ; arid 360° C. and upwards. (F. G. Dexter.)
Average yield of tar per ton of coal equals 1 cwt. equal to 10 gallons.
When tar is distilled the first portion volatilized is principally NH3 and some gases suspended in the hydrocarbons, then ammoniacal liquor and a small quantity of brown oil, or naptha, or " light " oil, of which from 5 to 20 per cent, is contained in the tar. At a higher heat first some almost colourless light oils come over, and then an olive or greenish heavy oil (•' dead oil "), next a greenish yellow fluid which becomes almost like butter. The contents of the retort consist of pitch.
Results of Distillation of Tar. (Professor Wanklyn.)
Ammoniacal liquor First light oils Second
Per Cent. 4-0 1-5 1-5
Creosote oils Anthracene oils Pitch
Composition of Tar (London). (Professor Lewes.)
Per Cent. 77-58 6-33 1-03
Per Cent. 22-0
4-0 67-0
Per Cent
0-61 14-50
Analysis of Tar from Caking Coal at Different Temperatures, (L. T. Wright.)
|
Yield of Gas Per Ton. |
Specific Gravity of Tar. |
Pitch. |
Light Naptha. |
|
Cubic Feet. |
Per Cent. |
Per Cent. |
|
|
6,600 |
1:086 |
29-89 |
|
|
7,200 |
1-120 |
|
9 |
|
8,900 |
1-140 |
||
|
10.160 |
1-154 |
|
3 |
|
11,700 |
1-206 |
64-08 |
1 |
Average Analysis of Tar.
London. ... .4-7 per cent.
Ammoniacal water . ...
Total light oils
Carbolic and creosote oils
Anthracene oils
Pitch (grams per 100 cubic centimetres
20-3 13-0
59-6
Country.
4 per cent.
3 „ 22 „
4 67
408 GAS ENGINEER'S POCKET-BOOK.
Average Percentage of Products from Ordinary Tar.
Ammoniacal liquor, gases and loss . . 9*2 per cent.
Light oils 1-4 „
Second light oils 1*6 „
Creosote oils 20-5 „
Anthracene oils 6-9 „
Pitch 60-4 „
The expression " light oils " means those oils which are lighter than water.
Distillation of tar (extreme case) average difficult to obtain.
Result of Distillation of 1,200 Gallons Tar.
Lancashire. London.
Ammoniacal liquor . . .30 gallons. 50 gallons.
First light oils . . . . 33 ., 20 „
Second light oils . . . 157 „ 20 „
Creosote oils 104 „ 250 „
Anthracene oils . . . 229 „ 50 „
Pitch 3i tons. 4 tons.
Analysis of Coal Tar. (E. J. Mills.)
Scotch
Constituents. London. Cannel.
Carbon 77-53 . 85-33
Hydrogen 6-33 . 7-33
Nitrogen 1-03 . 0-85
Sulphur 0-61 . 0-43
Oxygen 14-50 . 6-06
Tar from a gasworks where Boghead cannel was used gave the following results : —
Water, ammonia, salts. &c 6-0 per cent.
Light oil . 16-5 .,
Heavy oil 30-0 „
Pitch 41-5
Permanent gases 5-0 „
The quantity of tar increases with the percentage of 0 in the coal. (Dr. Biinte.)
ANALYSES OF COAL TAR. 409
Products from Distillation of Lancashire Coal Tar. 1,000 gallons Tar, TIG specific gravity equals 5*3 tons.
Per 1,000 Percentage
Gallons. by Weight. Per Ton.
a. Ammonia liquor, 4 ozs. . 25 gallons = 2-2 4| gallons.
1. First light oils . . . 28 „ = 2-2 5|
c. Second light oils . . . 131 „ = 10-6 24* M
d. Creosote oils . . 87 „ = 7-0 1G» „
e. Anthracene oils . . . 191 „ = 16-9 3G „ /.Pitch 3i tons =60-5 12 J cwts.
On further rectification, these distillates yiel 1 —
I. 90 per cent, benzol .... about 6 gallons. e. Solvent naptha „ 74 „
d. Carbolic acid „ 6£ „
e. 30 per cent, anthracene .... „ *50 cwt. Equal to pure anthracene . . . „ '15 „
Specific gravity of coal tar . . = 1-12 to 1-16. Specific gravity of cannel coal tar = *98 to TOG. 1 gallon tar at 1-16 specific gravity = ll'G Ibs. 1 cubic foot tar „ ,, „ = 72-5 Ibs.
Analysis of Coal Tar. (A. Colson.)
Coal used, Derbyshire, 18 per cent. : Nottingham cannel (producing
10,430 cubic feet of 17-caudle gas), 9 per cent. ; Yorkshire, 73 per cent. : —
Crude naptha, 30 per cent, at 120° C. . . G'79 gallons.
Carbolic acid, crude, 60° 1-14 „
Heavy naptha, 20 per cent, at 1GO° C. . 3-55 „
Creosote B 58-04 „
Ammoniacal liquor. 10 ozs 5-00 „
Napthalene 33-91 Ibs. '
Anthracene, 33 per cent. . . . . 13'60 „
Pitch 12-67 „
Products from One Ton or Tar (1886), (J. T. Lewis.)
Benzol (50/90) .... 5 gallons.
Naptha 2 .,
Carbolic, acid 5 '„
Creosote oil 50 „
Anthracene 30 Ibs. of 35 per cent.
Napthalene 2 cwts.
Pitch 11 „
Tar from Newcastle coals contains much napthalene and anthracene. Tar from Wigan coals contains much benzol and phenol. (Hornby.) Aniline (C12HyN) is obtained from the heavy tar oils by agitation
with hydrochloric acid, and decomposed by a slight excess of potash
or soda and twice distilled.
410 GAS ENGINEER'S POCKET-BOOK.
STATUTORY AND OFFICIAL REGULATIONS FOR TESTING THE ILLUMINATING POWER AND PURITY OF GAS.*
Extract from the Gasworks Clauses Act, 1871.
SECTION 28.
The undertakers shall cause to be provided, at the place prescribed and within the prescribed time, a testing place, with apparatus therein, for the purposes following, or such of them as may be prescribed by the special Act, that is to say : —
1. For testing the illuminating power of the gas supplied.
2. For testing the presence of sulphuretted hydrogen in the gas
supplied.
The said apparatus shall be in accordance with the regulations pre- scribed in Part I. of the Schedule A. to this Act annexed, or according to such rules as may from time to time be substituted in lieu thereof by any special Act, and shall be so situated and arranged as to be used for the purpose of testing the illuminating power and purity of the gas supplied by the undertakers, and the undertakers shall at all times thereafter keep and maintain such testing place and apparatus in good repair and working order.
SCHEDULE A. PAET I. Regulations in reject of Testing Apparatus.
1. The apparatus for testing the illuminating power of the gas shall consist of the improved form of Bunsen's photometer, known as Letheby's open 60-inch photometer, or Evans' enclosed 100-inch photometer, together with a proper meter, minute clock, governor, pressure gauge and balance.
The burner to be used for testing the gas shall be such as shall be prescribed.
The candles used for testing the gas shall be sperm candles of six to the pound, and two candles shall be used together.
2. The apparatus — (a) for testing the presence in the gas of sul- phuretted hydrogen. — A glass vessel containing a strip o"f bibulous paper moistened with a solution of acetate of lead containing 00 grains of crystallized acetate of lead dissolved in one fluid ounce of water.
SCHEDULE A. PART II. 1. ]\Iode of Testing for Illuminating Power.
The gas in the photometer is to be lighted at least fifteen minutes before the testings begin, and it is to be kept continuously burning from the beginning to the end of the tests.
Each testing shall include ten observations of the photometer, made at intervals of a minute.
* I am indebted to the proprietors of " The Gas World Year-Book " for permission to reproduce from that volume the illustrations in this section.— H. O'C.
ILLUMINATING POWER AND PURITY OF GAS. 411
The consumption of the gas is to be carefully adjusted to 5 cubic feet per hour.
The candles are to be lighted at least ten minutes before beginning each testing, so as to arrive at their normal rate of burning, which is shown when the wick is slightly bent and the tip glowing. The standard rate of consumption for the candles shall be 120 grains each per hour. Before and after making each set of ten observations of the photometer, the Gas Examiner shall weigh the candles, and if the combustion shall have been more or less per candle than 120 grains per hour, he shall make and record the calculations requisite to neutralise the effects of this difference.
The average of each set of ten observations is to be taken as repre- senting the illuminating power of that testing.
2. Mode of Testing for Sulphuretted Hydrogen.
The gas shall be passed through the glass vessel containing the strip of bibulous paper moistened with, the solution of the acetate of lead for a period of three minutes, or such longer period as may be prescribed ; and if any discolouration of the test paper is found to have taken place, this is *to be held conclusive as to the presence of sulphuretted hydrogen in the gas.
Extract from Memorandum issued by the Standards Department of the Board of Trade (July 1st, 1891), requiring Pkotometers to be verified and stamped.
Where the photometer, or apparatus for testing the illuminating power of gas, consists of the improved form of Bunsen's photometer, known as Letheby's open 60-inch photometer, or Evans' enclosed 100-inch photometer, then the official verification will, in accordance with established practice, include the burner, meter, minute clock, scale, governor, pressure gauge, and other subsidiary measuring instru- ments. A certificate of verification is, however, only issued if such photometers are of the Evans or Letheby forms hitherto recognised by the Department. — [The Board now also certify the table photometer.]
Directions for Using Standard Sperm Candles.
Cut a candle into halves, cut round half an inch from the new end of each piece, care being taken not to cut the wick, and slip off the small piece of spermaceti ; light the wicks and let them burn for about five minutes ; see if the wicks are central. If they are, let them burn for about twenty minutes, till they are in proper burning order, before commencing experiment.
When it is desired to extinguish the candles, touch the wicks first with a piece of spermaceti.
The candles should be kept in a cool place, in a proper tin candle- box.
NOTIFICATION OF THE METROPOLITAN GAS REFEREES-1900-1901. As to the Service Pipes to the Testing Places.
Each testing place shall be connected with the main or mains specified by the Gas Referees by a service rjipe, one service pipe to
412 GAS ENGINEER'S POCKET-BOOK.
each main, which proceeds directly from the street main or mains, and is without tap or branch or provision for connection of any kind outside the testing place. If obstruction of the service pipe is found, or if there is reason to think that the quality of the gas is suffering from any change occurring within the service pipe, the service pipe may be washed out in the presence of and by arrangement with the Gas Examiner, either with hot water alone or with any usual solvent, such as benzol, naphtha, or petroleum, but the use of such solvents is to be followed by a washing with hot \vater. In every case wrhere the service pipe is washed out the gas company shall send a letter to the Gas Referees explaining why the washing was considered necessary. No testing for illuminating power is to be made until after the hipse of an hour since the last washing out. The gas companies may, if they think fit, provide a tap and funnel in any testing place for the purpose of such washing out.
As to the Standard Lamp to be used for Testing Illuminating Power.
The standard to be used in testing the illuminating power of gas shall be a pentane 10-candle lamp which has been examined and certified by the Gas Referees. [The lamp is figured on p. 423.] The residue of pentane in the saturator shall, at least once in each calendar month, be removed, and it shall not be used again in any testings.
All pentane provided by the gas companies will be examined and certified by the Gas Referees, and will be sent to the testing places in one- pint cans which have been both sealed and labelled by them ; and no pentane shall be used in the testing places other than that which has been thus certified.
As to the Times and Mode of Testing for Illuminating Power.
The testings for illuminating power shall be three in number daily. But if the average of three testings of illuminating power falls below the prescribed illuminating power, a fourth testing shall be made.
It is required (Gas Light and Coke and other Gas Companies Act Amendment Act, 1880, sect. 7) : " That the tests for illuminating power shall be taken at intervals of not less than one hour." Also (sect. 8) "the average of all the testings at any testing place on each day of the illuminating power of the gas supplied by the company, at such testing place, shall be deemed to represent the illuminating power of such gas on that day at such testing place."
The photometer to be used in the testing places shall be the Table Photometer [figured on page 425]. The air-gas in the lamp is to be kept burning so that the flame is near its proper height for at least ten minutes before any testing is made. At the completion of every testing the air-gas is to be turned off : but if the interval between two testings does not much exceed one hour and the Gas Examiner is present during the interval, he may, instead of turning it off, turn it down low.
The gas burner attached to eacli photometer shall be a standard burner corresponding with that which has been deposited with the
ILLUMINATING POWER AND PURITY OF GAS. 413
Warden of the Standards in accordance with, among others, section 37 of the Gas Light and Coke Company's Act, 1876. A description of the standard burner to be used for testing gas is given [on page 422]. No burner shall be used for testing the illuminating power of gas that does not bear the lead seal of the Gas lleferees.
A clean chimney is to be placed on the burner before each testing.
The gas uu ler examination is to be kept burning so that the flame is about the usual height for at least fifteen minutes before any testing is made ; and no gas shall pass through the meter attached to the photo- meter except that which is consumed by the standard burner in testing or during the intervals between the testings made on any day and that which is used in proving the meter.
The paper used in the photoped of the photometer shall be white in colour, unglazed, of fine grain, and free from water marks. It shall be as translucent as is possible, consistently with its being sufficiently opaque to prevent any change in the apparent relative brightness of the two portions of the illuminated surface when the head is moved to either side. This paper should, when not in use. be covered, to protect it from dust ; and if it has been in any way marked or soiled, a fresh piece is to be substituted.
Each testing shall be made as follows : —
The index of the regulating tap shall be so turned that the gas flame gives rather less light on the photoped than the standard, and shall then be gradually turned on until equal illumination has been obtained. The position of the index shall then be noted. Next, the tap shall be so turned that the gas flame appears to give rather more light than the standard, and shall then be turned off until equality is again attained, and the position of the index shall be again noted. The double operation shall be repeated. In making these adjust- ments, a small alternating movement of the tap may be employed if the Gas Examiner finds that he can by this means make more con- sistent readings ; but, as stated, the tap is to be turned before each setting, alternately too high or too low. The mean of the four index positions shall be taken as that which gives true equality of illumina- tion. The index shall be set to this mean position, the equality of illumination verified, and the time that the hand of the meter takes to make two complete revolutions shall be observed.
In order to make this observation, a stop-clock shall be used by which the time which has elapsed since the clock was started can be read with an accuracy of at least half a second. The clack shall be started at the moment when the meter-hand points either to zero or to some other convenient mark, and a note shall be immediately made of the mark chosen. Exactly at the completion of the second turn of the meter-hand the Gas Examiner shall stop the clock. The time of two revolutions thus indicated by the clock is to be read to the nearest half-second, and found in the table given (page 426). From this and the reading of the aerorthometer, or a determination of the tabular number deduced from readings of the thermometer and barometer, the illuminating power of the gas is to be obtained, either directly or by interpolation. Only one figure after the decimal point need be entered when the result is above 16 ; where a lower result is found, both figures
414 GAS ENGINEER'S POCKET-BOOK*
should be noted and entered. A diagram giving the tabular numbers for different temperatures and pressures is given (pages 366-7).
The method of finding the illuminating power from the Table by interpolation may be illustrated by the two following examples : —
I. — Time, 1 min. 53 see. Heading of aerorthometer. 1*073. By the Table the illuminating power corresponding to this time of con- sumption and to the reading 1*070 is 16'12. while for the reading I'UHO it is 16*27. Thus, in this part of the scale, when the reading is 10° higher, the illuminating power is greater by 0*15 candle. Hence, when the reading is 3° above 1*070, the corresponding illuminating power is 16*12 + ^ X 0*15 = 16'165 candles, and the number to be returned is 16 '2.
II. — Time, 2 min. 1£ sec. Beading of aerorthometer, *984. The numbers in the Table under *980 are 15*81 for 2 min. 1 sec., and 15-94 for 2 min. 2 sec.; therefore, the number corresponding to H sec. is the half way number, 15-875 ; the number found similarly under '990 is 16*035. The increase for 10° is here 0*16 ; the number corresponding to the reading '984 is accordingly 15*875 + ± X 0*16 = 15-939 ; and the number to be returned is 15*94.
If, in very exceptional circumstances, the aerorthometer scale of the tables do not include the conditions that are met with, the Gas Examiner shall determine the illuminating power by means of one or other of the formula? printed below the-tables.
Each testing place must be provided with a chemical thermometer, divided into degrees on the Fahrenheit scale, and with a standard clock that will go for a week without rewinding.
The Gas Examiner shall, at least once a week, compare the stop- clock in the testing place with the standard clock or with his watch.
The Gas Examiner shall enter in his book the particulars of every testing of illuminating power made by him at the testing places, during or immediately after such testing ; and in the case of any testing which he rejects he shall also state the cause of rejection. No testing is to be rejected on the ground that the result seems improbable.
Times and Modes of Testing for Purity.
The testings for purity shall extend over not less than fifteen hours of each day, and shall be made upon ten cubic feet of gas. The gas shall be tested successively for sulphuretted hydrogen, ammonia, and sulphur compounds other than sulphuretted hydrogen, in the manner hereinafter prescribed. These testings must be started between 9 a.m. and 5.30 p.m., and must be concluded before 9 a.m. on the following morning. They are concluded by the action of an automatic lever-tap attached to the meter, which stops the passage of the gas when ten cubic feet have passed. A clock connected with the lever-tap is stopped at the same moment, leaving a record of the time ; and the tap of an aerorthometer is turned, leaving a record of the final conditions under which the gas was measured by the meter.
The liquids in the sulphur and ammonia tests, and the slips of paper in the tests for sulphuretted hydrogen, then contain the sulphur and ammonia which were present in the gas supplied to the testing place during the day which ended at 9 a.m. The chemical examination of
ILLUMINATING POWER AND PURITY OF GAS. 415
these liquids may be made on the following day, that is to say, after 9 a.m.
All connections between the following pieces of apparatus, in which the purity of the gas is tested, are to be on or above the surface of the table on which the apparatus stands.
I. — SULPHURETTED HYDROGEX.
The gas, as it leaves the service pipe, shall be pnssed through a small dry governor, and thence through an apparatus in which are suspended slips of bibulous paper, impregnated with basic acetate of lead.
The test paperfrom which these slips are cut is to be prepared from time to time by moistening sheets of bibulous paper with a solution of one part of sugar of lead in eight or nine parts of water, and holding each sheet, while still damp, over the surface of a strong solution of ammonia for a few moments. As the paper dries all free ammonia escapes.
If distinct discolouration of the surface of the test paper is found to have taken place, this is to be held as conclusive evidence that sulphuretted hydrogen is present in the gas. Fresh test-slips are to be placed in the apparatus every day.
In the event of any impurity being discovered, one of the test-slips shall be placed in a stoppered bottle and kept in the dark at the testing place ; the remaining slips shall be forwarded with the daily report.
II. — AMMONIA.
The gas which has been tested for sulphuretted hydrogen shall pass next through an apparatus consisting of a glass cylinder filled with glass beads which have been moistened with a measured quantity of standard sulphuric acid. A set of burettes, properly graduated, is provided.
The maximum amount of ammonia allowed is 4 grains per 100 cubic feet of gas ; and the examination of the liquid shall be made so as to show the exact amount of ammonia in the gas.
Two test-solutions are to be used — one consisting of dilute sulphuric acid of such strength that 25 measures (septems) will neutralise 1 grain of ammonia ; the other a weak solution of ammonia, 100 measures of which contain one grain of ammonia.
The correctness of the result to be obtained depends upon tne fulfilment of t\vo conditions : —
1. The preparation of test-solutions having the proper strength ;
2. The accurate performance of the operation of testing.
To prepare the test-solutions the following processes may be used by the Gas Examiner : —
Measure a gallon of distilled water into a clean earthenware jar, or other suitable vessel. Adel to this 94 septems of pure concentrated sulphuric acid, and mix thoroughly. Take exactly 50 septems of the liquid and precipitate it with barium chloride in the manner pre- scribed for the sulphur test. The weight of barium sulphate which 50 septems of the test-acid should yield is 13'8 grains. The weight
416 GAS ENGINEER'S POCKET-BOOK.
obtained with the dilute acid prepared as above will be somewhat greater, unless the sulphuric acid used had a specific gravity below 1-84.
Add now to the diluted acid a measured quantity of water, which is to be found by subtracting 13 '8 from the weight of barium sulphate obtained in the experiment, and multiplying the difference by 726. The resulting number is the number of septems of water to be added.
If these operations have been accurately performed, a second precipitation and Aveighing of the barium sulphate obtainable from 50 septems of the test-acid will give nearly the correct number of 13-8 grains. If the weight exceeds 13'9 grains, or falls below 13*7 grains, more water or sulphuric acid must be added, and fresh trials made until the weight falls within these limits. The test-acid thus prepared should be transferred at once to stoppe-red bottles which have been well drained and are duly labelled.
To prepare the standard solution of ammonia, measure out, as before, a gallon of distilled water, and mix with it 50 septems of strong solution of ammonia (sp. gr. 0*88). Try whether 100 septems of the test-alkali thus prepared will neutralise 25 of the test-acid, proceeding according to the directions given subsequently as to the mode of testing. If the acid is just neutralised by the last few drops, the test-alkali is of the required strength. But if not. small additional quantities of water, or of strong ammonia solution, must be added, and fresh trials made, until the proper strength has been attained. The bottles in which the solution is stored should be filled nearly full and well stoppered.
The mode of proceeding is as follows : — Take 50 septems of the test-acid (which is more than enough to neutralise any quantity of ammonia likely to be found in the gas), and pour it into the glass cylinder, so as to well wet the whole interior surface, and also the glass beads. Connect one terminal tube of the cylinder with the gas supply and the other with the meter, and make the gas pass at the rate of not more than two-thirds of a cubic foot per hour. Any ammonia that is in the gas will be arrested by the sulphuric acid, and a portion of the acid (varying with the quantity of ammonia in the gas) will be neutralised thereby. At the end of each period of testing, wash out the glass cylinder and its contents with distilled water, and collect the washings in a glass vessel. Transfer one-half of this liquid to a separate glass vessel, and add a quantity of a neutral solution of litmus, or other indicator in ordinary use, just sufficient to colour the liquid. Then pour into the burette 100 septems of the test-alkali, and gradually drop this solution into the measured quantity of the washings, stirring constantly. As soon as the colour changes (indi- cating that the whole of the sulphuric acid has been neutralised), read off the quantity of liquid remaining in the burette. To find the number of grains of ammonia in 100 cubic feet of the gas, multiply by 2 the number of septems of test-alkali remaining in the burette, and move the decimal point one place to the left.
The remaining half of the liquid is to be set aside, in case it should be desirable to repeat the volumetric analysis. This portion of the liquid is to be used in either of the two following cases : —
1. If the analysis of the first portion of the liquid show an excess
ILLUMINATING POWER AND PURITY OF GAS.
of impurity, the Gas Examiner shall forthwith give the notice A . vided for in the Acts of Parliament (the Gas Light and Coke CompaW^ Act, 1876, sect. 40, and others)-; and if the company think fit to be" represented by some officer, the second portion of the liquid shall be examined in his presence.
2. If the analysis of the first portion of the liquid should miscarry, or the Gas Examiner have any reason to distrust the result, he shall be at liberty to make an analysis of the second portion, provided that before doing so he give notice 'to the company, in order that they may, if they think fit, be represented by some officer.
Unless thus used it is to be preserved, in a bottle properly labelled, for a week.
III. — MEASUREMENT OP GAS AND OF THE RATE OP FLOW.
The gas which has been tested for sulphuretted hydrogen and ammonia shall pass next through a meter by means of which the rate of flow can be adjusted, and which is provided with a self-acting movement for shutting off the gas when 10 cubic feet have passed, for stopping a clock so as to indicate the time at which the testings terminated, and for turning the tap of the recording aerorthometer. The Gas Examiner shall enter in his book the time thus indicated, as also the time at which the testings began.
The clock required is a good pendulum clock, with a wire passing transversely through the case, behind the pendulum. Outside the case a lever arm is clamped to the wire, so that when liberated the arm will drop and turn the wire. Inside the case an arm is clamped to the wire, and at the end of the arm a flexible wire is fastened ; when the lever drops this flexible wire is brought into gentle factional contact with the pendulum, so as to stop it without shock.
The clock should be wound from the front, and both hands should be mounted so that they can be set independently, also from the front. It is desirable that the clock should be able to go for a week with one winding, and the. Gas Examiner must satisfy himself, from time to time, that the rating is nearly correct.
IV. — SULPHUR COMPOUNDS OTHER THAN SULPHURETTED HYDROGEN.
The testing shall be made in a room or closet where no gas is burning other than that which is being tested for sulphur and ammonia.
Pieces of sesquicarbonate of ammonia, from the surface of which any efflorescence has been removed, are to be placed round the stem of the burner. The index of the meter is to be then turned forward to the point at which the catch falls and will again support the lever- tap in the horizontal position. The lever is then made to rest against the catch so as to turn on the gas. The index is then turned back to a little short of zero, and the burner lighted. When the index is close to zero; the trumpet-tube is placed in position on the stand, and its narrow end connected -with the' tubulure of the condenser. At the same time the long chimney-tube is attached to the top of the condenser.
G.E. B E
418 GAS ENGINEER'S POCKET-BOOK.
As soon as the testing has been started a reading of the aerortho- meter is to be made and recorded. The mechanism for stopping the clock is then to be connected with the lever-tap of the meter, so that both may be stopped at the same moment, when 10 cubic feet of gas have passed through the meter. The clock is to be started and set right, and the time is to be recorded.
After each testing, the flask or beaker which has received the liquid products of the combustion of the 10 cubic feet of gas is to be emptied into a measuring cylinder, and then replaced to receive the washings
of the condenser. Next the trumpet-tube is to be removed and well washed out into the measuring cylinder. The condenser is then to be flushed twice or thrice by pouring quickly into the mouth of it 40 or 50 cubic centimetres of distilled water. These washings are brought into the measuring cylinder, whose contents are to be well mixed, and divided into two equal parts.
One half of the liquid so obtained is to be set aside in case it should be desirable to repeat the determination of the amount of sulphur which the liquid contains. This portion is to be examined under the same conditions as have been prescribed for the examination of the second portion of the liquid obtained from the apparatus used in testing for ammonia ; unless thus previously used, it is to be preserved, in a bottle properly labelled, for one week.
The remaining half of the liquid is to be brought into a flask or beaker, covered with a large watch-glass, treated with hydrochloric acid sufficient in quantity to leave an excess of acid in the solution, and then raised to the boiling point. An excess of a solution of barium chloride is now to be added, and the boiling continued for five minutes,
ILLUMINATING POWER AND PURITY OF GAS. 419
The vessel and its contents are to be allowed to stand. till the barium sulphate has settled at the bottom of the vessel, after which the clear liquid is to be, as far as possible, poured off through a paper filter. The remaining liquid and barium sulphate are then to be poured on to the filter, and the latter is to be well washed with hot distilled water. (In order to ascertain whether every trace of barium chloride and ammonium chloride has been removed, a small quantity of the washings from the filter should be placed in a test-tube, and a drop of a solution of silver nitrate added ; should the liquid, instead of remaining perfect y clear, become cloudy, the washing must be con- tinued until, on repeating the test, no cloudiness is produced.) Dry the filter, with its contents, and transfer it into a weighed platinum crucible. Heat the crucible over a lamp, increasing the temperature gradually, from the point at which the paper begins to char up to bright redness. (An equally good and more expeditious method is to drop the filter with its contents, drained but not dried, into the red- hot crucible.) When no black particles remain, allow the crucible to cool; place it, when nearly cold, in a desiccator over strong sulphuric acid, and again weigh it. The difference between the first and second weighings of the crucible will give the number of the grains of barium sulphate. Multiply this number by 11 and divide by 4 ; the result is the number of grains of sulphur in 100 cubic feet of the gas.
This number is to be corrected for the variations of temperature and atmospheric pressure in the manner indicated under the head of Illu- minating Power, with this difference, that the mean of the aerortho- meter readings found at the beginning and at the end of any testing shall be taken as the reading for that testing. The reading at the beginning of the testing is to be made by the Gas Examiner, who, before leaving*the testing place, will set the columns of mercury level in the two tubes of the instrument, and will connect the lever-tap of the aerorthometer with that of the meter. The fall of the lever of the meter will release a similar lever turning a tap which closes the tube of the aerothometer. The reading of the aerothometer as it stood at the end of the testing will require a small correction for the difference in level of the mercury in the two tubes, which is* to be made in the following manner : —
Let R be the corrected reading, i\ the actual rending of the aeror- thometer, ?'2 the reading of the companion tube, h the mean height of the barometer in units of the aerorthometer scale, a number which will be printed on each instrument, and is commonly 0'76. Then A + i\ — rv
R==r>x — i—
The correction by means of the aerorthometer reading may be made most simply, and with sufficient accuracy, in the following manner : — When the aerorthometer reading is between
•955--9G5, -966--975, '976--985, -986--995, diminish the number of grains of sulphur by 4, 3, 2, 1 per cent.
When the aerorthometer reading is between '996-1-005, no correction need be made.
BE 2 '
420 GAS ENGINEER'S POCKET-BOOK.
When the aerorthometer reading is between
1-006-1-015, 1-016-1-025, 1-026-1-035, increase the number of grains of sulphur by . . 1, 2, 3 per cent.
Example : —
Grains of barium sulphate from
5 cubic feet of gas . . . . 4'3 Aerorthometer
Multiply by 11, and divide by 4 11 reading, 1-'018
4)47-3
Grains of sulphur in 100 cubic
feet of gas (uncorrected) . . 11-82
Add 11-8 x jgg -24
Result :
Grains of sulphur in 100 cubic 12-1 grains.
feet of gas (corrected) . . .12-06
The aerorthometer reading is the reciprocal of the tabular number. The Gas Examiner shall, not less often than once a month, compare the aerorthometer reading with the reciprocal of the tabular number deduced from observations of the barometer and thermometer, and if there is a difference of more than one-half per cent, the instruments are to be readjusted.
As to the Mode of Testing the Pressure at which Gas is supplied.
Testings of pressure shall be made at such times and in such places as the Controlling Authority may from time to time appoint. In order to make this testing the Gas Examiner shall "unscrew the governor and burner of one of the ordinary public lamps, and shall attach in their stead a portable pressure-gauge. In places where incandescent burners are used for street lighting, one street lamp in each street or group of streets may be provided under the lantern with a branch closed by a screw stopper. The Gas Examiner shall in such cases connect the pressure-gauge by screwing to it an L-shaped pipe fitted with a union, by means of which it may be connected to the service pipe in the place of the screw stopper. The L-shaped pipe is to be of such dimensions as to enable the pressure-gauge to be fixed outside the lantern but at about the same level as the incandescent burner. It should be provided with a tap.
The gauge to be used for this purpose consists of an ordinary pressure-gauge enclosed in a lantern, which also holds a candle for throwing light upon the tubes and scale. The difference of level of the water in the two limbs of the gauge is read by means of a sliding- scale, the zero of which is made to coincide with the top of the lower column of liquid.
The Gas Examiner having fixed the gauge gas-tight, and as nearly as possible vertical on the pipe of the lamp, and having opened the cocks of the lamp and gauge, shall read and at once record the pressure
ILLUMINATING POWER AND PURITY OP GAS. 421
shown. From the observed pressure one-tenth of an inch is to be deducted to correct for the difference between the pressure of gas at the top of the lamp column and that at which it is supplied to the basement of neighbouring houses.
The pressure prescribed in the Acts of the three metropolitan gas companies is to be such as to balance from midnight to sunset a column of water not less than six-tenths of an inch in height, and to balance from sunset to midnight a column of water not less than one inch in height.
Meters.
Each of the meters used for measuring the gas consumed in making the various testings is constructed with a measuring drum which allows one-twelfth of a cubic foot of gas to pass for every revolution. A hand is fastened directly to the axle of this drum, and passes over a dial divided into one hundred equal divisions. The dial and hand are protected by a glass. In the meter employed in testing the purity of the gas, the pattern of dial for showing the number of revolu- tions and the automatic cut-off hitherto in use shall be retained, but in the meter employed for testing illuminating power, only the dial above described is needed. The stop-clock may be either attached to the meter or separate.
The meters used for measuring the gas consumed in making the various testings, having been certified by the Referees, shall, at least once in seven days, be proved by the Gas Examiners, by means of the Referees' one-twelfth of a cubic foot measure.
No meter other than a wet meter shall be used in testing the gas under these instructions.
[The G-as Referees prescribe that the gas shall be wholly free from sulphuretted hydrogen, that ammonia shall not exceed 4 grains, and that sulphur compounds shall not exceed 22 grains in winter and 17 grains in summer per 100 cubic feet of gas.]
[Official copies of the Gas Referees' notification, containing a number of appendices, can now be purchased by the public, price Is. 6d.]
422
GAS ENGINEER'S POCKET-BOOK.
GAS REFEREES' STANDARD BURNER.
(Applicable to both Old and New Regulations.)
The burner which has been adopted as the Standard Burner for testing gas was designed by Mr. Sugg, and was called by him " Sugg's London Argand, No. 1."
A half-sized section is appended, in which A represents a supply pipe, B the gallery, C the cone, D the steatite chamber, E the chimney.
The following are the dimensions of those parts of the burner upon which its action depends : —
Inch.
Diameter of supply pipes . . . U'US External diameter of annular
steatite chamber 0'84
Internal diameter of do. . . . O'iS
Number of holes 24
Diameter of each hole .... 0'045 Internal diameter of cone : —
At the bottom 1 '5
At the top 1-08
Height of upper surface of cone and of steatite chamber above
floor of gallery 0>(55
Height of glass chimney ... 6 Internal diameter of chimney . 1*875
TEN-CANDLE PENTANE LAMP. 423
TEN-CANDLE PENTANE LAMP.
Fig. 2. Fig. 1.
Mr. Harcourt's 10-candle pentane lamp is one in which air is saturated with pentane vapour, the air gas so formed descending by its gravity to a steatite ring burner. The flame is drawn into a definite form, and the top of it is hidden from view by a long brass
424 GAS ENGINEER'S POCKET-BOOK.
chimney above the steatite burner. The chimney is surrounded by a larger brass tube, in which the air is warmed by the chimney, and so tends to rise. This makes a current which, descending through another tube, supplies air to the centre of the steatite ring. No glass chimney is required ; no exterior means have to be employed to drive the pentane vapour through the burner.
[A, saturator. B, burner connected to saturator by indiarubber tube. S2, regulating cock. Sj, air inlet cock. C, chimney tube. D, exterior tube connected to interior of the burner by the connecting-box and tube B.J
THE TABLE PHOTOMETEft. THE TABLE PHOTOMETER.
425
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GLOSSARY OF TERMS.
427
GLOSSARY OF TEEMS IN USE IN GASWORKS.
(Sugg.)
|
English. |
French, |
German. |
|
Air. |
Air. |
Luft. |
|
Ash. |
0 end re. |
Asche. |
|
Bisulphide of carbon. |
Bisulphure de car- |
Doppelt Schwefelkoh- |
|
bone. |
leustoff. |
|
|
Burner. |
Bee. |
Brenner. |
|
Candle. |
Bougie. |
Kerze. |
|
Caimel. |
Cannelcoal. |
Kannelkohle. |
|
Carbonic acid. |
Acide carbonique. |
Kohlensauer. |
|
Carbonic oxide. |
Oxyde dc carbone. |
Kohlenoxyd. |
|
Cast iron. |
For fonte. |
Gusseisen Koheisen. |
|
Cement. |
Ciment. |
Cement. |
|
Chimney (lamp"). |
Chemine'e verre. |
Lampenglas. |
|
Clay. |
Argile. |
Thon. |
|
Coal. |
Houille charbon. |
Steinkohle. |
|
Coke. |
Coke. |
Coke. |
|
Exhauster. |
Extracteur. |
Auszicher. |
|
Fire brick. |
Brique refractaire. |
Chamottestein. |
|
Fire clay. |
Argile ., |
Chamotte. |
|
Gas fittings. |
Appareils a gaz. |
Gaseinrichtung. |
|
Gasholder. |
Gazometre. |
Gasbehalter. |
|
Gasholder curb. |
Corniere. |
|
|
Gas kitchener. |
Cuisiniere a gaz. |
Gas-kock und Brat- |
|
Herd. |
||
|
Gas main. |
Tuyau a gaz. |
Strassengasrohr. |
|
Gas pipe. |
Conduit a gaz. |
Gasrohr. |
|
Gas stove. |
Fourneau a gaz. |
Gasofeu; |
|
Gasworks. |
Usine a gaz. |
Gasaustalt. |
|
Hydrogen. |
Hydrogene. |
Wasserstoff. |
|
Inlet pipe. |
Tuyau d'entree. |
Einflussrohr. |
|
Iron. |
Fer. |
Eisen. |
|
Lamp. |
Lampe. |
Lamp. |
|
Lime. |
Chaux. |
Kalk. |
|
Marsh gas (methane). |
Gaz de marais. |
Sumpfgas-Grubengas. |
|
Meter. |
Compteur. |
Gasuhr. |
|
Nitrogen. |
Azote. |
Stickstoff. |
|
Outlet. |
Sortie. |
Ausfluss. |
|
Oxide of iron. |
Oxyde de fer. |
Eisenoxyd. |
|
Oxygen. |
Oxygene. |
Sauerstoff. |
|
Pitch. |
Brai. |
Pech. |
|
Pressure register. |
Mouchard. |
|
|
Retort. |
Cornue. |
Retorte. |
428
GAS ENGINEER'S POCKET-BOOK.
Glossary of Terms in Use in Gasworks. (Sugg.) — continued.
|
English. |
French. |
German. |
|
Shade. |
Abat-jour. |
Lichtschirm. |
|
Sheet iron. |
Tole. |
Schwarzes Blech. |
|
Sperm candle. |
Bougie de spermaceti. |
Walrathlight. |
|
Sperm oil. |
Huile de baleine. |
Walrathoel. |
|
Standard light. |
E talon photometrique. |
Normallicht. |
|
Steam. |
Vapeur. |
Dampf. |
|
Steel. |
Acier. |
Stahl. |
|
Stop-cock. |
Robinet. |
Hahn. |
|
Sulphur. |
Soufre. |
Schwefel. |
|
Sulphuretted hydro- |
Hydrogene sulf ure. |
Schwefelwasserstoff. |
|
gen. |
||
|
Tallow. |
Suif. |
Talg. |
|
Tap. |
Robinet. |
Hahn. |
|
Tar. |
Goudron. |
Theer. |
|
Valve. |
Valve. |
Ventil. |
|
Water. |
Eau. |
Wasser. |
|
Wax. |
Cire. |
Wachs. |
|
Wood. |
Bois. |
Holz. |
|
Wrought iron. |
Fer battu. |
Abschlageisen. |
INDEX.
A BSORBTNG hydrocarbons, 326 J\. Absorptive power of solids, 339
1 iime, 372
water, 196, 374
Absorption of coke, 232
heat by air, 243
light by globes, 309
• Weldon mud, 274
Abutments of arches, 143 Accumulator ram, friction of, 151 Acetate of lead test papers, to prepare,
342 Acetylene absorbed by water, 391
• and air, 390
iron burners, 391
, description of, 391
explosive mixtures, 391
• for gas engines, 390
, illuminating value of, 353
in coal gas, 391
lighting power of, 391 quantity from carbide, 391 testing for, 378 toxicity of, 391
value as enricher, 390
under pressure, 391
Acid in scrubbers, 263
, standard solution of, 343
, 10 per cent, specific gravity of, 375
Action in sulphided lime purifiers, 273
of lime on H2y, 272
oxide on H2S, 269
Admitting air in third purifier, 275 Advantages of tar firing, 242 r- turned and bored pipes,
292
Aggregate for concrete, 73 Air and acetylene, 390
— blast for water gas, 393
— carburetted with tar, 275
— compression, 246 — , dry, weight of, 328
— , effect on illiiminating power, 244 — , flow of, in pipes, 281
— for removing bad smell from lime, 274
— in purification, 274
Air in smith's forge, 229
sulphided purifier, 275
— , liquid, density of, 328 — , pressures of, 323
— required for combustion of coal, 316 ; of other fuels, 259, 346
furnaces, 155, 244
lights, 311 — , specific heat of, 241 — , speed of sound in, 328
— valves for purifiers, 201
— vitiated by lights, 305 — , volume of 1 lb., 327
— , with all lime purification, 274
sulphided lime, 273
Weldon mud, 274
for
Alcohol vapour in mains, 302 Ale and beer measure, 44 Allport's waterproof roofing, 80 Allowance for lap of plates, 213
snow on roofs, 79
waste on rivets, 213
wind on roofs, 79
Alloys, melting points of, 250, 335 Aluminium, joining, 229 American wire gauges, 96 Ammonia combinations, 264
gas, tension of, 263
in crude gas, 235
• process of purification, 201
removal, 196
removed by scrubbers, 262
• required for purification, 263
•, standard solution of, 344
test solution, 343
, to prevent loss of, 265
, yield of, 233, 262
Ammoniacal liquor, analysis, 264
, contents of, 263
on oxide, 275
Amount of hydrocarbon for enriching. 389
sulphate from liquor, 404
Am yl -acetate standard, 370 Analysing flue gases, 240 Analysis of ammoniacal liquor, 264
INT'EX.
psjdBML -.v- I^B,
spent oxide, 999
:'.-. Ml
Aqpmt Tapour, calculating for, 965
Axe of aide, 41
Arch pipes, currea in, 160
Arci.rf, aMHMtaJ .-. Ii3
, depth of, 143
Are* of readrwsrf*. 163; of girders, 132 ; of foal Ban, 100; of oral, 41; of purifiers, 1ST; of retort etort
156; of roof, to calculate, 78 ; of seg- ment, 41 ; of tar and liquor tanks, 165 ; of workshops, 228. • coveted by tight, 358
of circlet, 24
— washen and scrubbers, 195
A-h. h <
Ash-pans, water in, 243
jESt teMMsX 14-i
for tanks, 209
AsyhritaiMI, •
MB
hMt M
specific
:. ;:s
M
A^s^yfali after, ±- Avoiding loss in capping, Avoirdupois we ' Axl-r 1% MB
BABBITT metal, 99 E^ kfa*j rts»* -.rii;;, -04
. 165
pressure, correcting for, S BaS04 into grains snlphur, 38
piers, safe load on, 75 weight of, 7fi
rehifire strength of, 138
[>tmd,202 girders, 132 span between, 183
tore, 44 Betting, leather, 1S7
, preset-ration of, 187
, strength of, 188
"-"- " — of, 188
r. ,154
glass tones, 324
temt tfateadaris, -:-:3
of, lltf
force tending to drive off, 291 • enricher, 301
-.•^ •..'^•::.'.^
pared with napthaloM, 387
-. 4^,CdissofiS!grpower of water,
IU, VW*
, enriening power of , 301 , stability of gas with, 387
INDEX.
431
Best heats for cooking, 317
Birmingham gauges, 96
Bituminous coal, composition of, 251
Blast mains for water gas, 393
Blocks, cement, 74
in cups of gasholders, 224
Block tin tube, weight of, 124
Blowers for water gas, 393
Blue flame at outlet of flue, 242
Board of Trade regulations for 138
thermal unit, 340
unit of electricity,
Boards for scrubbers, 195
Bog ore, analysis of, 267
Boiled linseed oil, 77
Boilers, 166
chimney area for, 176 chimneys for, 176 4*BJc""*g data for, 171
draught for,°176'0
feeding. -2V fire grate area, 173 flaws in plates, 175 flues for, 176
for steam heating, 316
foundations, 176 furnace tubes, pressures on, 174 horse-power of, 174 Lancashire, 173 overheating, 175 rivets for plates, 175 proportions of, 170 settings for. 176
settling, 1S1
chimney for, 178
pipes for^
Bolt centres in angle irons, 143
heads, weight of, 102
threads, Whitworth, 126
Bolts and nuts, proportions of, 102
, strength of, 103
Bond. English. 70
-, FSsh, 71
, hoop-iron, 67
Books damaged by gas-light, Ml
Boring for tanks, 202
Boxing round valves, 165
Boyle's law, 365
Brake horse-power, 166
Brass, sheet, weight of, 124, 130
Breaking joint in gasholder sheets, 210
strength, 101
weight on steel joists, 133
Breeze is tel. -2*2
from coke breaker, 332
fuel, 317
Eri.k
Bricks, cohesive force of, IB
, good, to tell, 69
, quality of, 67, 69
Bricklayers hod measurement, 73 work of, 72
htcnsMnt, MsnanH on, 75
i^tpri-;. rim nt e:
1S3
.. . «y~m
of Dibdin's standard, 369 -, number required, 811
-.serriee yielded by, 305
BH
<-'* *i -"nilTr—fr VABUmiMnsK *V
Bursting Jbrce of water, 203 strength of boiler shell,
r>:f areas. ~>
sue of exhausters, 168
strength of tank walls, 207
Calories, 340
Calorific power developed by steam
of Dowson gas, 317
value for illuminating power,
of career.. lro
— coal gas, 340
— coke, 260
432
INDEX.
Calorific value of gases, 815
gas in different burners,
315
Calorimeter, Mahler's, 249 Camber in girders, 132 Candle balance, 360
ends in photometers, 360
Candles, old, 361
, per gallon, 385
, standard, 360
Caimel, as an enricher, 386 Cantilever type gasholders, 223 Capacities for pumps, 185
of circulating tanks, 192
meters, 321
scrubbers, 195
station meters, 229
Capacity, measures of, 44
Carbide, yield of, 390
Carbon atoms in enrichers, 301
bisulphide, 273
, calorific value of, 156
di-oxide, action of lime on, 272
, causes loss of light, 347
, description of, 352
in boiler flues, 261
water gas, 394
, per minute of run, 395
produced by gases, 331
lights, 305
reduction of illuminating
removal of, 27]
power by, 267
, testing for, 378
escaping xmconsumed, 397
, heat energy of, 341
, units from, 244
in coke, 382
furnaces, 241
retorts, 247
sloping retorts, 247
• monoxide, diluting effect of, 255
, water in, 394
Carbonic acid, effect on rabbits, 399 Carbonising, 233
at different temperatures,
236
high temperatures, 233
( best heat for, 234
-, labour required for, 245
tar, 251
Carburetted water gas, analysis of, 352,
392 , heating value of,
399 • • , length of flame
with, 399 Carburetting air with tar for purification,
275
for testing, 370
Carburettor for water gas, 393 Carburine, condensation with, 402
, quantity required, 386
, retained by gas, 386
Carcel standard, 370 Care of gasholders, 279
Carriages to gasholders, 224 Carrying capacity of pipes, 285 Case hardening, 100 Cast-iron beams, 137
columns for gasholders, 210
, composition of, 99
girders, 138
pipes, coating for, 123
, weight of, 114, 281
Casting pipes, 288
Castings, contraction of, 99, 229
Catch purifiers, 271
Cause of napthalene, 301
Caustic lime, to test, 372
Ceiling, reflecting power of, 307
Cement and sand, strength of, 72
blocks, 74
bricks, strength of, 68
, coefficient of expansion of, 74
for repairing i ipes, 292
— rust joint, 127
, Portland, use of, 73
, Roman, 74
Chains, equilibration, for gasholders, 214 , notes on, 111
, strengths of. 109
Chalk, lime made from, 270
, value of, 270
Changes of wood to coal, 381 Channel iron curbs, 224 Charcoal, wood, gas from, 252 Charges, deep, 233
, 6-hour, and 4-hour, 238
Charging, heat lost during, 244
, time required, 246
unevenly, 233
Charles' law, 332, 365
Cheapest curb, 213
Check purifiers, 271
Checker work in water gas plant, 394
Chimney area for boilers, 176
as ventilating flue, 308
dimensions, 177
Chimneys, batter of, 179
, Board of Works rule, 178.
, building notes, 181
, coal consumption, 178
, division walls in, 158
, draught in, 158
, power of, 179
, fire-brick lining to, 179
for boilers, 176
products works, 404
, heat at exit of, 181, 261
, lightning conductors for, 159
near buildings, 158
, proportion, 177
, retort house, 158
, vacuum in, 159
, velocity of gases in, 179
, wind pressures on, 179
Circle, arc of, 41
, properties of, 41
Circles, areas of, 24
-, circumferences of, 24
Circular retorts, 155
INDEX.
433
Circular saws, rate of, 228 Circulating tanks, capacities of, 192 Circumferences of circles, 24 Claus process of purification, 201 Clay burning, 65
for bricks, analysis of, 69
, safe load on, 75
retorts, 155
, gas lost from, 244
, life of, 223
Clearing napthalene from condensers,
256
Climatic effects on distillation, 239 Clinkering, 243 Clinkers in concrete, 209 Coal, analysis of, 250
, bituminous, analysis of, 380
, calorific power of, 342
consumed by chimneys, 178
• , consumption of, in trains, 232
, conversion on carbonising, 251
• dust in air, 329
— — , evaporative power of, 176
, experiments on, 382
, exposed to air, 231
gas, acetylene in, 391
compared with Dowson gas, 400
• , loss by compression, 403
• , refrigerated, 401
handled by stokers, 246
igniting point of, 232 measurement of, 145 moisture in, 251 nitrogen in, 265 per-centage of, in use, 2.50 products of distillation, 235 required in furnaces, 244 soot from, 317
space occupied by, 145 to obtain specific gravity of, 380 stacking, 231
storage, 145
, tie-rods in, 146
walls, 146
tar constituents, 406
distillates, 406
testing, 381
• , to ascertain if good, 252
• used to fire retorts, 239
, various, weight of, 145
, ventilation of, 145
Coating for gasholders, 280
pipes, 123, 291
service pipes, 292
Cochineal, to prepare, 343 Coefficient of expansion of cement, 74 r,aseSj 330
metals, 334
friction, ISO
linear expansion, 89
Cohesive force of bricks, 203
• resistance of tank walls, 203
Coke, absorption of, 232 , analysis of, 241
breaker, breeze from, 232
, carbon in, 382
CUB,
Coke, contents of, 244
drawn easily, 244
fired water tube boilers, 175
for boiler in water gas plant, 898
Dowson gas, 401
furnaces, ash in, 241
generator, 394
from Peebles process, 402
, hard, to obtain, 244
in scrubbers, 195
-, measurement of, 145
, moisture in, 244
, organic matter in, 243
• removed by conveyor, 155
stacking, 232
, to estimate, 381
used to fire retorts, 239
• , water required to slake, 244
, weight of, 145
, yield of, 244
Collapsing pressure of boiler tubes, 173 Colour of gas purified by oxide, 268 test, Harcourt's, 376
Coloured lights, 311 Colours for drawings, 60
of different temperatures, 248
Columns, gasholder,. strength of, 222
of brick, strength of, 68
resistance of, 223
Combination of nitrogen in coal, 384 Combining effect of ammonia, 263
equivalents of ammonia and
sulphuric acid, 404
power of oxide, 268
weights of elements, 322
Combustion, conversion of sulphur on, 382
, gaseous products from, 34G
of fuels, 259
-, air or oxygen re-
quired, 259
gases, temperature of,
332 , oxygen required to support,
328
, products of, 356
, to find heat of, 347
Commercial benzol, 389
Comparative cost of different lights, 313
— duty of burners, 348
pressures, 299
— prices of French and English
gases, 304 ,
strengths of metals, 130
weights of metals, 128
Comparison of engines, 401
Weldon mud and oxide, 274
wind pressures on circular
objects, 219 Composite pipe, weight of, 123 Composition of cast iron, 99
fire-clay, 152
fuels, 382
— gas after scrubbers, 266 at different heats, 207
— London gas, 319
FP
434
INDEX.
Composition of natural gas, 351 • producer gases, 241
purified gas, 277
the atmosphere, 828
VanSteenburggas, 400
water gas, 351
Compressed air, 246
in retort houses, 154
Compressing coal gas, 403 Compression, contraction of iron by, 213
in gas engines, 190
• of earths by head of water,
207
generator gas, 401
Pintsch gas, 402
strains in curbs, 224
Concrete, 65
aggregate for, 73
clinker in, 209
fire-bricks in, 209
mixing, 73, 209
strength of, 75
tanks with iron bands, 207
volume of spaces in, 74
water required for, 74
water-tight, 207 Condensation, effect of, 255
of steam, 182
, speed of, 164
— under pressure, 165
with carburine, 402
Condensed gas, impurities in, 256 Condensers, 163
, areas of, 163
, best temperature for, 255
1 bye-passing, 258
, doing without, 255
for water gas, 393
in sulphate plant, 404
, loss of heat in, 164
mains, fall in, 165
, temperatures in, 254
, valves for, 164
Condensable vapours in hydraulic mains,
254 Condensing, 255
acetylene, 391
below 60° P., 256
thoroughly before scrubbers,
256
water gas, 306, 396
Conducting power of solids, 338 Conductivity, electric, of metals, 98 Conductors, lightning, 181 Connecting services, 296 Connections, bye-passes to, 196
• , dimensions of, 116
• , finding leaks in, 194
for pumps, 184
— • — in works, size of, 162
— to purifiers, 198 Constant level water gauges for station
meters, 319
Constituents of coal tar, 406 Construction of purifiers, 198 Consumption in gas engines, 193
Consumption per head, 151
of coal in trains, 232
fuel per I.H.P., 176
gas per head, 319
Contact of gas with water, 279 Contents of ammoniacal liquor, 263
pipes, 90, 281
Continuous girders, 139 Contraction of castings, 99, 229 holders on rising, 226
iron by compression, 213
Conversion of coal on carbonising, 251
sulphur on combustion, 382
Converting per cent, to cubic inches per
gallon, 378
Conveyor, saving by, 162 Cooking, best heats for, 317
-, gas required for, 31-4
Cooling gas engines, 192
excessively, 255
surfaces for condensing, 163
Coping, 72
Copper, expansion of, 213
nails, weight of, 97
pipes, weight of, 124
Cork refuse, gas made from, 253 Corners in English bond, 70 Flemish bond, 71
Cornish boilers, proportions of, 170 Correcting by tabular numbers (diagram), 368
for aqueous vapour, 365
barometrical pressure, 365 rate of burning of candles
(diagram), 362 ; rule, 361
• gas (dia-
gram), 364 ; rule, 363
temperature, 365 and. pressure,
366
Corrugated iron, weight of, 97 Cost of brickwork tank, 203
• enrichment, 385
fitting gas to railway carriages,
402
gasholders. 210, 219
metal tanks, 203
motors per horse-power, 315
settings, 156
six-lift gasholder, 219
water gas, 399
Covering power of paint
paint, 7l> sheet lead, 9(3
• varnish, 77
tar and liquor tanks, 165
Coverings to roofs, 79
tops of benches, 154
Covers for purifiers, 201
Cracks in tank backings, 204
Crane hooks, proportions of, 150
Cranes, hydraulic, 151
Crank shafts, diameter of, 187
Creosote oil for exhausters, 258
Croll's sulphate plant, 404
Crown, radius of, 225
sheets, riveting to trussing, 21
INDEX.
435
Crown sheets, thickness of, 226 Crowns of gasholders, 213
, strains on, with different rises,
213
, Walker's rule, 214
Crude carburetted water gas, analysis of,
gas, ammonia in, 235
residuals from, 235
oil, products of, 381
Crushing, resistance to, 68
stress on curbs, 227
Cube roots, 1
Cubes, 1
Cubic feet to cubic metres, 58
measure, 44
metre gas in English money, 304
metres to cubic feet, 59
Cupolas for melting iron, 144 Cupping, to avoid loss in, 209 Cuprous chloride, to prepare, 344 Cups and grips, 224 Curb, best form of, 210
, compression strains in, 223
, crushing stress in, 227
for trussed holders, 210, 213
, steel, to gasholder, 211
, weight of, 244
Curbs with two angles, 211
Curves, elevation of outer rail on, 149
in arch pipes, 160
, resistance of, 149
, to set out, 147
Cutting tools, angles of, 228
• , speed of, 228
Cyanides, best temperatures for. 265
, reaction of, 196
Cyanogen in coal gas, 265, 270
liquor, Prussian blue, 384
, to recover, 265
, when produced, 262
Cylinders, engine, thickness of, 168
, expansion of, 210
, hydraulic thickness of, 151
of wrought iron and steel,
strength of, 171
, size of, to drive exhausters, 168
, steel, strength of, 172
, temperatures in, 168
Cylindrical beam, strength of, 222
DAMAGE to books by gas-light, 308 Damp coals, sulphur from, 233
courses, 66
• sand, resistance of, 204
Danger of fire with liquor tanks, 165
Daylight, power of, 307
Dead loads in building, 87
Deals, 82
Decagon, length of side of, 41
Decimals of a foot, 48
• • hundredweight, 46
mile, 47
pound weight, 48
ton, 49
Decimals of a year, 47
an inch, 47
£1,45
Decomposition by light, 360
of water, temperature of,
394
Deep charges, 233 Delivery pipes for pumps, 184 Delta metal, 99 Density of liquid air, 328 Depth for pipes, 291 of arches, 143
gas mains, 279
lead in ordinary joints, 285
lifts, 212
yarn in pipe joints, 292
Designing boilers, 171 Detecting oxygen in coal gas, 378 Determining caking of coal, 380 Diagram for correcting by tabular num- bers, 368
for rate of burn- ing of candles, 362 ; gas, 364 • Harcourt's colour test, 377
of comparative prices of French
and English gases, 304
• number of feet for one penny,
303
• rolled iron joists, 134
tabular numbers, 366
-thickness of wrought-iron
tanks, 208
weight of pipes, 120 and
pressures of gas- holders, 221
• showingsulphur from BaSOi,
383 Diagrams from gas engines, 191
of distributing power of pipes,
282 Diagonal bracing to gasholder framing,
210, 220 Diameter of crank shafts, 187
exhaust pipes, 182
Dibdin's pentane burner dimensions, 371
standard, burner of. 369
Dies, 228
Different temperatures, colours of, 248
Diffusion of gases, 279
Digging, 64
Diluting effect of carbon monoxide, 255
— hydrogen, 255 Dimensions of bends, 116
boilers, 170
chimneys, 177
dry meters, 320
feed pumps, 186
flanged connections, 118
pipe flanges, 289
pipes, 286
rack and pinion valves, 293
socket joints, 289
station meters, 230
turned and bored pipes,
•wet meters, 319
F F2
436
INDEX.
Dinsmore process, gas made by, 253 Dip pipes, 160
, jointing, 160
Discs for photometers, 350 Disillumined gas plus benzene, 302 Dissolving napthalene, 301
in condensers, 256
388
— power of water on benzene, &c.,
Distance apart of slating laths, 79
for photometric standard, 359
lights are visible, 310
Distillates from coal tar, 406 Distillation, fractional, 235
, products of, 381
, coal, 235
Distilling shale oil, 385
. tar, results, 407
Distortion of standards, 223 Distributing hydraulic power, 151
mains, 292
power of pipes (diagrams),
water in scrubbers, 195
Distribution, 281
of secondary air, 157
District pressures, 300 Dividing a line, 61 Division walls in chimneys, 158 Divisions of photometer bars, 358 Dodecagon, length of side of, 41 Doing without condenser, 255 Dowson gas, calorific power of, 317
, coke from, 401
compared with coal gas, 400 -, explosive force of, 400 -, gasholder for, 401 -, heating value of, 401
• in engines, 193
per horse-power, 400
producer gas, 400
steam required in, 401
Drains for retort houses, 154 Draught for boilers, 176 . iu chimneys, 158
• power of chimneys, 179
Drawing coke early, 244 • paper, sizes of, 59
Drawings, to colour, 60 Drilling holes in mains, 291 Drills, speed of, 228 Drums of station meters, 230 Dry measure, 44
meters, particulars of, 320
, tests of, 321
Durability of water gas flame, 399
test, 357
Duty of various burners, 306
EARTH backing, resistance of, 203 Earths, natural slopes of, 62, 202
, weight of, 62
Earthy matters in lime, 270 Effect of air in purification, 274 carbonic acid on rabbits, 399
Effect of carbonic acid on sulphided lime
purifiers, 273 cold on tower scrubbers, 262
condensation, 255
heat, 247
on C0.2, 235
H2S, 235
metals, 114
273
heating to 1,000% 235 heavy gasholders, 212 HaS on sulphided lime purifier,
pressure on flames, 356
meters, 321
retorts, 244
radial rollers, 211 tangential rollers, 211 temperature on scrubbers, 262
Effective heating duty of gas, 341 pressure on pistons, 169
Efficiency of incandescent burners, 348 non-conducting materials,
182
oil engines, 194
Egner's method of preparing lime, 271 Elastic force of aqueous vapour, 326 strength, 101
Elasticity, modulus of, 101, 143 Electric lamps, incandescent, 313 units, 89
- ,
Electrical conductivity of metals, 98
Electricity damaging pipes, 291
Elementary bodies, 322
Elevation of outer rail on curves, 149
Eliminating power of oxide, 268
Engine journals, 186
Engines 166
coal required for, 176 parison of, 401
com
- crank shafts, 187
- gas, 190
- oil, 194
English bond, 70
-, strength of, 72
Enrichers, boiling points of, 386
, sulphur in, 386
Enriching apparatus, position for, 402
power of benzene, 301, 388
Peebles plant gas,
402
processes, 385 value of oil gas, 386
• carburetted water gas,
Enrichment, cost of, 385
, per gallon, 385
Eqiution of water gas production, 398 Equilibration chains to gasholders, 214 Equivalent liquid measures, 56
measures of length, 56
, mechanical, of light, 356
normal solutions, 346
of heat, 166
weights, 56
Escape of CO in ordinary furnaces, 242 Estimating ash, 381
INDEX.
437
Estimating coke, 381
sulphur in coal, 381
temperatures, 249
Ethane, boiling point of, 353
, illuminating value of, 353
Ethine, description of, 301 Ethylene and oxygen mixed, 387
, description of, 352
, illuminating value of, 353
Evaporating with different qualities of
gas, 356 Evaporation of water, 332
under furnaces, 155
, power of ooal, 250
fuels, 259
Evils of over-exhausting, 258 Examining heat of retorts, 234 Excavating, 64 Exhaust from gas engines, 401
- pipes, 182
- from gas engines, 191
- , noises in, 192
Exhausters, 166
- , horse-power required, 167
- , lubricating, 258
- , to calculate size of, 168 Exhausting, 258
-- - • at 120° P. , 258
- , evils of over, 258 Expansion and weight of water, 333
- by heat, 330
- in steam pipes, 182
- linear, coefficients of, 89
- of copper, 213
- cylinders, 210
- freezing water, 337
- gases, 323
- , coefficient of, 332
- iron, 213
- • and cement, 209
by tension, 213
liquids, 332
bv heats, 338
metals, coefficients of, 334
oxide, 268
Experiments on coal, 382 Exploding coal dust, 329 Explosions in water gas plant, 394
• with acetylene, 391
— petroleum vapour, 385
Explosive mixtures, 191
, force of, 329
, kindling, 329
, limiting, 329
, value of, 193
power of Dowson gas, 317, 400
Expulsion of burnt gases from gas engines,
gases from water, 196
Extension of gasholder space, 210 Eye, power of, 358
FACING and pointing, 74 Factors of safety, 89 — — on. stones, 76
Factory chimneys, 178
floors, loads on, 82
Fall in condenser mains, 165 gutters
Falling water, horse-power of, 87 Fall required in mains, 291 Fastenings for purifiers, 200 Feeding boilers, 260 Feed pumps, dimensions of, 186
water, heating, 261
Feet for Id. (diagram), 303 Felt asphalted, 80
, weight of, 80
Ferroeyanide of iron, 276 Finding leaks in connections, 194
— mains, 292
proportions of enriching gas, 885
Fire bars, thickness of, 173
, space between, 155
Fire-brick lining to chimneys, 179 Fire-bricks in concrete, 209 -, safe load on, 75
, test of, 153
, weight of, 68
Fire-clay blocks, weight of, 153
, composition of, 152
, notes, 153
specific heat of, 152
, specmc neat or, loa
Fire, danger of, with liquor tanks, 165 Firegrate area in boilers, 173 Fires, heats of, 317 Firing, gaseous, 157 Fittings for wrought-iron tubes, 203 Fixing meters, 321
Flame, gas, cause of luminosity in, 355 temperatures, 354
Flames, effects of pressure on, 356 in rare atmospheres, 308
, oxygen required to support, 357
, theory of formation of, 311
•, temperatures of changes in, 353
Flanged connections, dimensions of, 118 Flanges, area of, to girders, 132
— • • for pipes, dimensions of, 289
of cast-iron tanks, 203
•,proportions of, 122
to purifiers, 198
Flat plates, strength of, 143
pointing, 74
• rolled iron, weight of, 91
Flaws in boiler plates, 175
Flemish bond, 71
Floor joists in basements, 82
retort houses, 154
Floors, loads on, 82
•, safe loads on, 78
Flow of air in pipes, 281 Flue gases in boil
ers, 261 .proper proportions of, 240
Flues, arrangement of, 15'
, blue flame at outlet of, 242
for boilers, 176
gas stoves, 314
, size of, 158
, temperatures in, 154
, vacuum in, 241
438
INDEX.
Flux for soldering, 124 Flywheels, safe speed of, 187 Fog in photometer rooms, 358 Footings, 65
Footpaths of tar concrete, 146 Force of explosive mixtures, 329
the wind, 215
water (bursting), 203
pumps, 186
tending to drive off bends, 291
Forcing gas down mains, 321 Foot, decimals of, 48
Foul main, area of, 160
temperature, 160, 254
Foundations, 64
for boilers, 176
tanks, 202
in water, 65
, pressures on, 65
Fractional distillation, 235 Freezing of water in tanks, 203
mixtures, 337
points, 333
— of benzene, 388
French and English gases, comparative
prices, 304
iratus, 427
Friction, coefficient of, 186
in condensers, 165
of accumulator ram, 151
to separate tar, 159
Front walls to benches, 155 Frost, action on mortal1, 74
in tanks, 279
Fuel, Andrew's patent, 260
, composition of, 382
, consumption per I.H.P., 176
, depth of, 157
, evaporative power of, 259
in generators, 393
of breeze, 317
, petroleum as, 176
, required for water gas, 394
- in regenerative settings,
239
sulphate plant, 405
Fuels, air required for, 346
, combustion of, 259
, space over, 155
, heating power of, 260
, temperature to convert to CO,
Furnace efficiency, to estimate, 155
flue seams for boilers, 176
Furnaces, air required in, 155, 240, 244 C in, 241
coal required in, 244
generator, 157
labour required for, 245
regenerative, 157
repair of, 243
water evaporated by, 243
Fusible alloys, melting points of, 250 Fusing point of napthalene, 256 Fusion, latent heats of, 338 > , temperatures of, 250
GAIN with gaseous fuel, 241 Galvanised slate nails, 96 Gas, analysis of, 349
and air in Bunsen burners, 312
incandescent burners, 347
, benzene from,
, carburine retained by, 386
discharged through mains, rules, 281
, effective heating duty of, 341
engines, 190
— , acetylene for, 390
, consumption in, 193
, diagrams, 191
, exhaust, 401
pipes, 191
for tramcars, 192
, heat units lost in, 193
, horse-power of, 191
, mechanical efficiency of, 191
, meters for, 192
-, pressures in, 190, 401 , scavenging, 193
-, starting, 193
, stopping, 193
, thermal efficiency of, 166
enriched per gallon of oil, 385
evaporates gasolene, 402
flames for ventilation, 311
for motive power of different
illuminating powers, 340
from condensers, analysis of, 256
iron and steam, 386
wood, 387
charcoal, 252
, heat units from, 340
heating before combustion, 308
, illuminating power of, given in
table, 426
in gas stove flues, 314
generator furnaces, 240
, lifting power of, 318
, specific heat of, 336
, to obtain specific gravity of, 354
weight of, 354
, velocity of, in chimneys, 179
in railway carriages, 402
leaving retorts, 253
liquor, testing for CO.2, 374
free ammonia, 374
lost from clay retorts, 244
made from cork refuse, 253
by Dinsmore process, 253
from peat, resin, sawdust, 253
mains, depth of, 279
making process, Browne's, 387
meter unions, 320
passed through sawdust and sulphur,
, pressures of, 323 retains benzol, 301 stove notes, 314
small orifice, 2£
supply pipes, 315 ly required for cool
, supply required for cooking, 314
, temperature entering purifiers, 268
tubing, weight of, 297
INDEX.
439
Gas valve testing, 292
washed in a tar seal, 253
with mineral oil, 325
works site, 151
yielded by tar, 252
Referees' standard burner, 422
Gaseous firing, 157
fuel, gain with, 241
products from combustion, 346
Gases, diffusion of, 279
Gasholder bell, to ascertain weight, 214
, care of, 279
carriages, 224
columns, strength of, 222
contraction of on lifting, 226
Gasholders, cost of, 210, 219
, curbs trussed, 210
, equilibration chains for, 214
, general notes, 210
guides, 220
, spiral, 220
for Dowson gas, 401
in gales, 279
joints, strength of, 225
of cantilever type, 223
, painting, 212, 279
, pressure of, 214
pumps, 209
sheets, rivets required for,
side sheets, thickness of, 212
single lift, 210
strains on top sheets, 210
, Wyatt's rules, 225
tanks, 202
-, frost in, 279 to increase weight of, 210 trussing, 212 weight of, 214
(diagram), 221
212
Gasolene, 302
evaporated by gas, 402
Gauges, mercury, 357
, pressure, 357
— , in decimals of 1 inch, 89
Gearing, rope, 189 Generator for water gas, 393
furnaces, gases in, 240
, gas compression of, 401
gases, proportions of COa in, 242
, heat produced in, 158
setting, 157
Generators, fuel in, 393
, temperatures in, 393
German words for gas apparatus, 427 Girders, area of flanges to, 132
— bearing surface for, 132
— camber on, 132
— cast iron, 138
continuous, 139
— relative strength of, 138
— thickness of web plates for, 139
— wrought iron, notes on, 139 Glass sheet, thickness of and weight of,
77
tube, to bend, 324
Globes, absorption of light by, 309 Glossary of terms, 427 Glycerine for meters, 321 Governor bell area, 321
cones, 321
Grabs, saving by, 152 Graduating photometer bars, 359 Grains sulphur from grains
(diagram), 383 Granite, analysis of, 76
piers, safe load on, 75
Grammes, £c., to convert, 58 Grates, heat evolved by, 316 Gravel, safe load on, 75 Grips and cups, 224 Ground area required, 151
, bearing power of, 202
under mains, 291
Grouting in steel tanks, 203 Guide framing notes, 220
rollers, 224
Gun cotton, heat of explosion, Gussets to gasholders, 210 Gutters, fall in, 80 Gyration, least radius of, 141
HALF-round iron, weight of, 130 Handholes in hydraulic mains, 159 Harcourt colour test, 376 Harcourt's pentane unit, 369 Hard coke, to obtain, 244 Hardening tools, colours of, 100 Haunching, 229 Head of water, 300 Heat absorbed by air, 243
at exit of chimney, 181, 261
conducting power of metals, 97
solids, 338
— , effects of, 247
equivalent, 166
. evolved by gas flame, 308
open grates, 316
, expansion by, 330
from 1 Ib. of different substances,
335
• in Peebles retorts, 402
• lost by unit of surface, 339
• when charging, 244
• of combustion of fuels, 259
to find, 347
retorts, to examine, 234 secondary air, 241
produced in generator, 158
— , radiant, 89
required to gasify tar, 402
of different fires, 317
, specific, 88
, transmission of, 175
units, 166
evolved by substances, 341
from carbon, 244, 397
gas, 340
hydrogen, 398
generated by lights, 307 lost in gas engines, 193
440
INDEX.
Heating and lighting by same gas, 356
coal, to indicate, 232
duty of gas, effective, 341
. . feed Avater, 261
gases, analysis of, 395
. — gas for combiistion, 308
power of fuels, 200
surface for boilers, 173
value of carburettcd water gas,
Dowson gas, 401
Heats, best for cooking, 317 Height of lamps, 309
lifts, 210
purifiers, 201
roof trusses in retort houses,
152
Hefner- Alteneck's burner, 370 Hemp ropes, strength of, 109 Heptane, 302, 353 Hexagon, length of side of, 41 High-pressure pipes, thickness of, 289
temperatures, carbonising at, 233
Hill's process, 265 Hod, bricklayer's, measurement, 73 Holes, drilling in mains, 291 Hoop iron in tank walls, 205
, weight of, 127
Hoops to tanks, 205 Horse-power of boilers, 174
Dowson gas, 400
falling water, 87
gas engines, 191
rope gearing, 189
required to pass gas, 1GG to raise water, 186 nth town gas, 301
Horse-powers, to calculate, 166 Horses, power of, 63 Hot lime sulphided, 274 Hourly make of gas, 237
quality of gas, 238
specilic gravity, 237
Housing exhauster plant, 166 Hundredweight, decimals of, 4G Hydraulic cranes, 151
mains, 159
levelling, 159
main liquor analysis, 253
overflows, 159
tar, 253
supports, 159
— , temperature in, 254
valves, 161
, water in, 253
water seals in, 160
power, 151
, distributing, 151
rams, loss in, 88
pipes, loss of head in, 151
cylinders, thickness of, 151
Hydrocarbons, amount for enriching, 389
-, temperature of produc-
tion, 233
-, to absorb, 326
-, illuminating value of, 355
Hydrochloric acid, normal, 345 Hydrogen, diluting effect of, 255
escaping unconsumed, 307
, heat units from, 398
-, lifting power of, 318
H->S, action of oxide upon, 269 , test for, 375
IGXITING point of coals, 202 Ignition of gas engines, 190 Illuminating agents, relative values of, 305
power by calorific values,
•from equal areas of
360
flames, 303
lost by air, 244
, table giving, 426
value of acetylene, 353
ethane, 353
ethylene, 353
methane, 353
values of hydrocarbons, 355 Impurities in condensed gas, 257 crude gas, 235
gas after scrubbers, 266
Incandescent burners with gas and air,
electric lamps, 313
Inch, decimals of, 47 Increasing weight of holders, 210 I.H.P., to calculate, 169 Indicating heating of coals, 232 Indicators to prepare, 343 Inertia, moments of, 136, 144 Inhalation of adults, 308 Injecting air into purifiers, 275
oil in water gas plant, 393
Inlet pipes to holders, 224
Inner lift, stability of, 224 stays, 211
Inorganic matter in coke, 243
Intensity of light, 310
Internal pipe fittings, size of, 309
Inverted arches, 66
Iron bauds in concrete tanks, 207
bars in concrete, 209
• burners and acetylene, 391
chains, strength of, 109
.contraction of, by compression, 213
, expansion of, by tension, 213
, expansion of, 213
, flat rolled, weight of, 91
• , half-round, weight of, 130
hoop, weight of, 127
joists, 82
pipes, weight of, 114
retorts for tar carbonisation, 251
sheet, weight of, 124
tanks, 203
on bad ground, 202 .
testing, 112
tubes, safe pressure on, 174
JET photometer, 261, 357 Joining aluminium, 229 - platinum, 229
INDEX,
441
Jointing for ascension pipes, 160
mouthpieces, 154 petroleum pipes, 397 h l
pipes with lead, 292
Joints in clip pipes, 160
- gasholders, strength of, 225
- stonework, 76
- of millboard, 292
- pipes, depth of yarn in, 292
- ,testing with soap, 292 Joists, iron, 82
-- rolled iron, diagram of, 134
- timber, 82
- „ safe load on, 86
- wooden, 137 Joule's law, 166, 340
- equivalent of heat, 166 Journals, engine, 186
- and space between, 183
TTEEPING right temperature in purl
IV tiers, 201
Keys, proportion of, 187
Kindling explosive mixtures, 329
T ABOUR required for furnaces, 245
JJ to carbonise, 244
Laming material, 274 Lamps, height of, 300 Lancashire boilers, 173
, proportions gf, 170
Latent heat, 338
of evaporation, 335
fusion, 338
liquefaction, 338
Laths, angle iron, 142
, for slating, distance apart, 79
Latticed standards, resistance of, 223 Layers of material in purifiers, 198 Laying lead, 80
mains, 291
permanent way, 148
slates, 78
Lead jointing, 292
laying, 80
nails, 96
pipes for services, 292
pipe, weight of, 123
sheet, covering power of, 96
, thickness of, 80
, usual thickness of, 80
, weight of, 80
test papers to prepare, 342
, to unite, 97
, white, to test, 77
Leakage in district, 300 Leak, finding in mains, 292 Leaks, in conections, to lind, 194
tanks, 205
Least radius of gyration, 141 Length, measures of, 43
of flame with carburetted water
gas, 399
different gases, 356
Length of side of decagon, 41
dodecagon, 41
hexagon, 41
— octagon, 41
Levelling hydraulic mains, 150 1 lability of water to freeze in tanks, 203 Lifting power of gases, 318 purifiers, 201
Lifts, depth of, 212
Light absorbed by globes, 309
, areas covered by, 358
, carbon di-oxide produced by, 305
, comparative cost of, 313
, decomposition by, 360
from standard burner, 369
— — , heat units generated by, 307
-, lost by addition of air,' 347
, mechanical equivalent of, 356
, minimum required, 307
, theory of, 354
, velocity of, 356
Lighting and heating by same gas, 856
power of acetylene, 391
table, 309
up water gas plant, 393
Lightning conductors, 181
for chimneys, 159
Lime, absorptive power of, 372
, action on CO2 and H2S, 272
, caking in purifiers, 270
— , combining with water, 271
, earthy matters in, 270
, increase of bulk when slaked, 271
, made from chalk, 270
— , quantity required to purify, 270
required for CO-2, 270
. sheds, 198
slaking before use, 271
testing, 372
, thickness on grids, 271
, water for testing, 342
in, 271
, weight of, 270
, wet, for purifying, 271
Limestone, value of, 270 Limiting explosive mixtures, 329 Limit of heat in settings, 240
weights of wrought iron, 140
Linear expansion, coefficients of, 89 Line, to divide, 64 Lining water gas vessels, 393 Linseed oil, boiled, 77 raw.
Liquefaction, latent heats of, 33£ Liquid air, density of, 328
fuel, 242
measure, 44
measures, equivalent, 56
Liquids, expansion of, 332
by heat, 338
Liquor, amount of sulphate from, 404 , analysis of, 264
freed from C02) 263
from condensers, contents of, 256
in hydraulic mains, 253
— scrubbers, 196
412
INDEX.
Liquor made from coal, 165
-, ounce strength of, 375
, standard test solution for, 343
tanks, 165
, testing for CO.2, 374
— free ammonia, 374 Lithium hydride, 353 Litmus papers, 342
to prepare, 343
Load on roofs, 78 , safe, on piers, 75
rolled iron joists, 134
Loads, dead, in buildings, 87 , live, on buildings, 87
on floors, 82
Loam earth, resistance of, 204 Locomotives, heated by petroleum, 244
, tractive force of, 148
Logarithms, 1
described, 23
London gas, analysis of, 349
, composition of, 319
Long measure, 43
pipe condensers, 167
Loss by storage, 279
of ammonia, to prevent, 265
head in hydraulic pip'cs, 151
heat in condensers, 164
when charging, 244
— gas in purifiers, 267
light through gas travelling, 301
weight by stacking coal, 231
Lowe oil gas, analysis of, 392 Lubrication for exhausters, 258 Luminosity, cause of, in gas flame, 355 Luminous effect of flame areas, 314 Lumps in settings, 243
Lutes in purifiers, 198
, steam in, 224
Luting materials, 244
MACHINE belting, 187 stoking, space for, 153
Mahler's calorimeter, 249 Mainlaying, 291 Mains 281
— coating for, 291
covered with felt, 291
depths for, 279
dimensions of, 286
drilling holes in, 291
fall required in, 291
in works, of wrought iron, 165
small services from, 291
temperatures in, 300
• testing in district, 291
— with sleepers under, 291 Maintaining flame at constant height, 36. Maintenance of metal tank, 203
Make of gas per hour, 237
liquor, 165
Making oxygen, 276
roads, 146
- sulphuric acid, 405 Manilla ropes, strength of, 189
Man power, 63 Man's strength, 228 Manure, sulphate as, 406 Marks on photometer bars, 359 Mariotte's law, 365 Marsh gas, description of, 352 -, particulars of, 325
Materials for luting, 244
roof, weight of, 78
required for railway, 148
settings, 156
weight of, 60
Mathematical tables, 1 Maximum wind pressure, 216 Measurement of coals, 1 45 coke, 145
Measures and weights, 42
of capacity, 44
length, 43
Measuring pipes, 293
Mechanical efficiency of gas engines, 191 steam engines, 106
equivalent of light, 356
Melting iron, cupolas for, 144 • points, 247, 330
of alloys, 250, 335
elements, 322
metals, 98. 334
solids, 334
Mending broken pipe, 292
Men employed in carbonising, 245
required for water gas plant, 393
Mercury, comparison of, 88
gauges, 257
, pressure of, 299
weight of, 357
Metals, comparative strength of, 130 weights, 128
coefficient of expansion of, 334 effect of heat on, 114 electrical conductivity of, 98 heat conducting power of, <»7 melting points of, 98, 334 safe stresses on, 128 specific heats of, 334 weight of square foot of, 128
Methane, description of, 352
illuminating value of, 353
Meters at high and low pressures, 321
, capacity of, 321
, dry average tests of, 321
, effect of, on illuminating power of
gas, 321
, fixing, 321
, glycerine for, 321
for gas engines, 192
, station, 229
, to prevent freezing, 321
, wet, particulars of, 319
, unions for, 320
Methyl orange, to prepare, 343 Metric equivalents, 56
liquid measure, 56
easures of length, 56
Metropolitan Building Act, 72 Mile, decimals of, 47
INDEX.
443
Millboard joints, 292 Minimum light required, 807 Mixing concrete, 73, 209
gases, 279, 234
puddle, 204
water at different heats, 339
Mixture for stucco, 73 Mixtures, freezing, 337 Modulus of elasticity, 101, 143 Moist air in photometer rooms, 358 Moisture in air, 311
coal, 251
coke, 244
Moments of inertia, 136, 144
Money, to convert to decimals of £1, 45 Monier system, 74 Mortar, 72
, best sand foi', 73
, in frost, 74
, strength of, 72
, water required, 73
Morticing, 229
Motive power from acetylene, 390
gases, 194
Motor, cost per horse-power, 318 Mouthpieces, jointing for, 154
, size of, 155
, weight of, 160
, yield per, 157
Multipost gasholder framing, 222
NAILS, copper, weight of, 97 for slating, zinc, 79
, lead, slating, 96
, slate galvanised, 96
Names of gas apparatus in French and
German, 410 Napthalene, 310 and cannel, 386
as an enricher, 302
compared with benzene, 387
, description of, 352
, fixing point of, 256
— in condensers, 164
scrubbers, 262
tar, 409
— works, 256
, preventing deposition in
works, 256
, tests for, 256
, to clear from condensers, 256
with dry gas, 256
Natural gas, composition of, 351
slopes of earths, 202
Newcastle coal, ash from, 251
Nitrate of soda compared with sulphate,
405 Nitrogen, combination in coal, 384
in coals, 265
for sulphate, 404
reduces light, 347
Noises in exhaust pipes of gas engines,
192
Nominal horse-power, 166 Non-conducting materials, 182
Non-conductors for steam pipes, 184 Normal hydrochloric acid, 345
oxalic acid, 345
sodium carbonate, 345
•hydrate, 345
solutions, equivalent, 346
sulphuric acid, 345
Notes on boilers, 173
• chains, 111
• gas stoves, 314
guide framing, 220
pumps, 184
riveting, 108
ropes, 111
ventilation, 311
wrought-iron girders, 132
Number of burners required, 311
feet for Id. (diagram), 303
Numbers, to square, 41 Nuts, proportions of, 102 , weight of, 102
OBLIQUE illumination, 307 Obtaining specific gravity of gases
Octagon, length of side of, 41 Oil engines, 194
— for exhausters, 258
— gas tar, analysis of, 396
— as paint, 277 — , water in, 397
— linseed boiled and raw, 77
— , pressure injected at, in water gas
plant, 393
•— , sperm, light from, 402 Oils, storing, 232 Old candles, 361 Oleflant gas, description of, 352 Olefine series, particulars of, 325 Ordinary joints, weight of lead in, 285 Oscillation in retorts, 247 Otto cycle gas engines, 190 Ounce strength of liquor, 375 pullet pipes to holders, 224 [)val, area of, 41
Overflow to hydraulic main, 159 Overheating boilers, 175 Dverturning of wind and snow, 223 Oxalic acid, normal, 345 Oxidation of sulphur compounds, 274 Oxide, analysis of, 267
back pressure from, 268
combining power of, 268
compared with Weldon mud, 274
expansion of, 268
heating when new, 269
in paint, 280
new, 268
of iron, effect on CS2, 267
paint, 77
purifiers, reaction in, 268
, purifying power of, 268, 373
surface required, 272
, revivifying, 373
sheds, 198
444
INDEX.
Oxide, spent, analysis of, 269
for cyanides, 269
• testing, 373
, thickness of layers, 268
, to revivify, 268
, value of, when spent, 269
, weight of, 268
Oxidising gasholder sheets, 211 Oxygen added to gas, 385
and ethylene mixed, 387
Photometer rooms, ventilation, 358 • - , shadow, 358 table, the, 425
Photometers with sliding candles, 300
Piers, safe load on, 75
Piles, 64
- , safe load on, 75
Pillars of brick and stone, 69
pine, breaking load on, 84
consumed by lights, 305
, detecting in coal gas, 378
purification, 275
required by acetylene, benzene,
ethylene, marsh gas, 355
for combustion of fuel,
259
purification, 276
328
to support combustion,
Pine beams, safe load on, 85
pillars, breaking load on, 84
, safe load on, 75
Pintsch system, 402 Pipe, broken, to mend, 292
condensers, 163
, composite, weight of, 123
fittings, internal, size of, 309
flanges, proportions of, 122
joints, depth of yarn in, 292
, temporary, 292
to prepare, 276
>AINT, covering power of, 76 Painting gasholders, 212, 279 gas stoves, 314
-- purifier covers, 277 Paint, oxide of iron, 77 Paper, drawing, sixes of, 59 Paraffin series, particulars of, 325 Paris, plaster of, 74 Particulars of dry meters, 320 -- wet meters, 319 Pavements, tar for, 317 Paving, York, weight of, 76
- slabs, 74
Peat, gas made from, 253 Pedestal proportions, 186 Peebles oil gas as an enricher, 402
- process, 402
- , coke from, 402
, gas from tar by, 402
flames, 357 j , repairing cement, 292
, wrought iron, thickness of, 131
, casting, 288
, coatings for, 123, 291
Pipes, contents of, 90
, copper, weight of, 124
damaged by electricity, 291
, depth underground, 291
, dimensions of, 286
distributing power of (diagram),
Pens for Pentane
registering pressure gauges, 319 , 371, 423 unit, Harcourt's, 369
Percentage of coal in its use, 250 Permanent way work, 148 Peroxide of iron, 373 Perpendicular, to set out, 64 Petroleum, analysis of, 386 -- , as fuel, 176 -- furnaces, 244
- heated locomotives, 244 -- lamp, light from, 307
- pipes, to joint, 397 -- tank, to protect, 397
- vapour explosions, 385 Phenanthrene, 353 Photometer bar, divisions of, 358 -- graduating, 359
- discs, 359
with three spots, 359
jet, 357
rooms, moist air in, 358
— , size of, 358
282
drilling holes in, 291 effects *of rough insides, 291 fall required in, 291 for gas stoves, 315 — steam heating, 316 in bad soils, 291 lead, weight of, 123 measuring, 296 outside covered with felt, 291 service, coating, 292 testing, 288 weight of, 114
, (diagram), 120
with sleepers under, 291
Pistons, effective pressures on, 169 Pitch for briquettes, 317
— pine beams, safe load on, F5 Placing concrete, 209
puddle, 204
Planing purifier plates, 200
Planks, 82
Plant for semi-water gas, 401
Plaster of Paris, 74
Plates, allowance for lap of, 213
, flat, strength of, 143
in tanks, 203
transverse strength of, 140
Platinum, jointing, 229 Pointing, 72
and facing, 74
flat and tuck, 74
Poor gas deposits napthalene, 250 Porosity of stone, 76 Portland cement, use of, 73 stone, analysis, of, 76
INDEX.
445
Portland stone piers, safe load on, 75 Position for enriching apparatus, 402 Potassium hydroxide, 344 Pound sterling, decimals of, 45
weight, decimals of, 48
Pounds water heated by gases, 331 various sub- stances, 331
Power from calcium carbide, 17(3 , hydraulic, 151
of daylight, 307
horses, 63
men, 63
oxide to remove sulphur, 269
puddle to retain water, 204
reflecting heat, 89
the eye, 358
water fall, SS •
• to dissolve benzene, &c.,
388
required to raise water, 184
, results of, 63
Preparing oxygen, 276 Preservation of belting, 187 scaffold cords, 72
timber, 81
Pressure from calcic carbide, 391
washers, 196
in gas engines, 190, 401
— puddle tanks, 205
— retorts, 247
— water gas shells, 393 gauges, 357
pens for, 319
of air blast in water gas, 393
— column of water, 324
— gasholders, 214
(diagram), 221
plane, 206
mercury, 299
snow on gasholders, 214
water, 299
• against a vertical
217
at different levels, 207
on tank sides, 206
vapour, 327
wind, 216 at different heights,
on circular objects, 218
• • in different places, 216
on different areas, 217
• — — spheres, 219
boiler furnace tubes, 174
— district, 300
flames, 356
foundations, 65
• guide columns, 218
retorts, effect of, 244
tank walls, 203
safe on boilers, 174
Pressures thrown by lime purifiers, 271 Preventing boiler incrustations, 261
deposition of napthalene in
works, 256
meters freezing, 321
Preventing oscillation in retorts, 165
priming, 261
, — stopped pipes, 2i6
Primary air in furnaces, 240 Priming, to prevent, 261 Producer and water gas mixed, 398
gas and flame temperature, 385
. , Siemens, 400
' — gases, composition of, 241
Producers, steam required for, 243 Production of aniline, 409 Products of coal, 255
. — combustion, 356
from burners,
- crude oil, 381
- distillation, 381
of coal, 285
tar, 381
works, chimneys, 404
Propane, 353
Proper height of lamps, 309 Properties of circles, 41 Proportions of belts, 188
boilers, 170
• bolts and nuts, 102
. CO-2 in generator gases, 242
chimneys, 177
crane hooks, 150
enriching gas, to find, 385
keys, 187
pedestals, 186
pipe flanges, 122
riveted joints, 104, 175
rivets, 107
tar concrete, 317
teeth of wheels, 187
tie-rods, 142
treads and risers to stair-
cases,
washers, 102
Protection areas of lightning conductors,
181 Prussian blue, 196, 276
iu cyanogen liquor, 384
Puddle tanks, pressures in, 205
, mixing, 204
, placing, 204
weight of, 204
Pulleys for rope driving, 188 -, rims, width of, 187
Pump notes, 184 Pumps, 166
• — , capacities of, 185
for gasholders, 209
Punches, 228 Pure air, contents of, 311 Purification by ammonia, 201, 263 Glaus process, 201
with oxygen, 275
Purified gas, composition of, 277
* Lowe oil gas, analysis of, 392
Purifier connections, 198
covers, 201
fastenings, 200
— — - lutes, 198
446
INDEX.
Purifier seals, 148 Purifiers, 197 , area of, 197
for sulphur purification, 197
, height of, 201
in sulphate plant, 404
> lifting, 201
, loss of gas in, 267
Purifying, 267
power of oxide, 268, 3V3
sheds, 197
• value of lime, 372
water gas, 396
Purlins, angle iron, 142
Purity of benzol, 388
Putlogs in scaffolding, 72
Putty for temporary pipe joints, 292
Pyrogallic acid, to prepare, 345
Pyrometers, 249
/DUALITY of bricks, 67 v^J -- gas per hour, 238 Quantity of acetylene from carbide, 391 -- cyanogen obtainable, 276 -- lime for purifying with
oxygen, 276 -- riveting in gasholders, 211
sulphur absorbed by oxide,
269
compounds from
coal, 273
T) ACK and pinion valves, dimensions of,
±1 293
Radial rollers, effect of, 211
Radiant heat, 89
Radiating power of solids, 339
Radius, least gyration of, 141
of crowns, 225
protection of lightning con- ductors, 181 Rails, 149
, strength of, 131
Railway carriages, gas in, 402
, materials required for, 148
Rainfall, maximum, 79
per hour, 79
Raising temperature of purifiers, 275
water, power required for, 185
Rags soaked with oil, 326
Rams, hydraulic, 88 Rate of station meters, 229
travel through purifiers, 197
Raw linseed oil, 77
Reaction in oxide purifiers, 268
of cyanides, 196
liquor and sulphuric acid, 404
oxide when revivifying, 269
Reciprocals, 1
Recovering cyanogen, 265 Red litmus paper, to make, 342
lead, setting of, 2SO
Reduction of temperature of waste gases, 243
Reduction of illuminating power by C02, 267
pressures in pipes, 281
Reflecting power of ceiling, 307 - solids, 339
•radiant heat, 89
Reflection of different substances, 311 Refrigerating coal gas, 401 Regenerative settings, 157
, fuel required in, 22
Regulations for testing, 410
Relative carrying capacities of pipes, 285
strength of beams, 138
— girders, 138 values of illuminating agents,
305 Removal of ammonia, 196
CO2, 271
CS>2 by scrubbers, 263
cyanogen compounds, 277
sulphur compounds, 272
tar, 255
Removing dip pipe seals, 160 tar, 164
Rendering tank walls, 209 Repair of furnaces, 243 Repose, angle of, 62 Residuals from crude gas, 235 Resin, gas made from, 253 Resistance of beams, 136
cohesion of wall, 203
curves, 149
damp sand, 204
earth backing, 203 lattice standards, 223 loam earth, 204
round cast-iron columns,
trains, 149
web plate standards, 223
weight of tank walls, 203
to crushing, 68
-, stones, 75
- loads, safe, 75
- shearing, 106
- torsion, 107
- traction on roads, 147 Results of distilling tar, 407
- power, 63 Retort, clay, life of, 243
- house, area required, 154
- chimney, 158
- , constructing, 151
- drains, 154
- , floor joists for, 154
, roof trusses for, ] 54
houses, compressed air in, 154 , ventilation of, 154 -, width of, 154
Retorts, 153
carbon in, 247
circular, 155
clay, 155
efleqt of pressure in, 244
for Peebles process, 402
heat of, to examine 234
INDEX.
447
Retorts, iron for tar carbonisation, 251
, oscillation in, 247
, space above coal, 233
around, 15-1
, temperature in, 254
, through, 155
, velocity of gases in, 234
, yield per square foot, 234
Reversing photometer discs, 359 Revivification of oxide in air, 273 Revivifying oxide, 373
, reaction, 269
Right angles to set out, 64
Rising pipes, curves in, 160
Riveted joints, proportion of, 104, 175
to plates, strength of, 107
Riveting crown sheets to trussing, 211
gasholders, 212
notes, 108
, quantity of, in gasholders, 211
thick to thin plates, 213
Rivets, allowance for waste on, 213
heads, weight of, 106
, proportions of, 107
required for gasholder sheets, 212
. , shearing resistance of, 108
strain on, 226
size of, for boiler plates, 175 plates, 106
strength of, 105
Road making, 146
- tramways, 147 Roads, gradients in, 147 Rocks, weight of, 62 Rod«of brickwork, 69 Rods, round, strength of, 130 Rolled joists, diagram, 134
- iron, weight of, 91
- T-iron, strength of, 142
Rollers radial and tangential, effect of, 211
Roman cement, 74
Roof, area, to calculate, 78
- coverings, 79 Roofing, Allport's waterproof, --- , Willesden, SO
Roof materials, weight of, 78
- sheeting, corrugated, 97
- trusses, height of, in retort house, 154
Roofs, allowance for snow on,
- , curved, 80
, load on, 78
, wind allowance on,
Room heating, 316
- temperature, 308 Rope driving pulleys, 188
- gearing, 189 Ropes, notes on, 111
- , safe working loads on, 112
- , strains round pulleys, 112
- , strength of, 109
- , wire, on pulleys, 232 Round rods, strength of, 130
- station meter, dimensions, 230 Rule for correcting for rate of burning of
gas, 363
Rule for height of lamps, 309
position of hoops to tanks, 205 thickness of tanks, 205 weight of pipes, 115
weig
, to find intensity of light, 310
Rumford photometer, 358
Rusting of wrought iron framing, 220
Rust joint cement, 127
S
AFE load on floors, 78 piers, 75
rolled iron joists, 134 timber joists, 86
pressure on boilers, 174 resistance to loads, 75 stresses on metals, 128 Safety, factors of, 89
on stones, 76
tubes in blast mains, 393
valves, 176
Safe working loads on ropes, 112
Salts in tar, 235
Sand and cement, strength of, 72
, best for mortar, 73
, value of in mortar, 72
, in mortar, size of, 73
, resistance of, 204
Saturated hydrocarbons, 325 Saturator, temperature in, 405 Saving by conveyor, 152
grabs, 152
steam jacketing, 168
Sawdust, gas made from, 253 Saws, best rate for, 228 Scaffold cords, to preserve, 72 Scaffolding, 72 Scavenging gas engines, 193 Schneider's heat testing cones, 249 Screw threads, 125 Scrubbers, ammonia removed by, 262 and washers, 195
, boards for, 195
, effects of temperature upon,
filled with coke, 195 for water gas, 393 , napthalene in, 262 , surfaces in, 195 , water required in, 262 -, wetting material in, 262
Scrubbing and washing, 262
Seals of purifiers, 198
Seams in furnace flues, 170
Seasoning timber, 81
, time required for, 83
Secondary air, distribution, 157 heat of, 241 in furnaces, 240 warming, 158
Seger's cones, 249 Segment, area of, 41 Semi-water gas, 401 Separating tar by friction, 159 Service pipes, coating, 292 size of, 296
448
INDEX.
Service yielded by burners, 305 Sen ices, connecting, 290
from small mains, 291
of lead pipe, 2;>2
— to photometers, 303 Setting out curves, 147
right angles, 04
Settings, cost of, 156
, covering for, 154
for boilers, 176
generator, 157
, limit of heat in, 240
.materials required for, 156
, steam under bars, 243
, temperatures in, 241
, walls of, 154
Sewerage, 66
Shadow photometers, 358
Shafts for boilers, 181
shal«- oil, distillim:. 885
Sheard's tests for NHa, CO-2, H2S, 375
Shearing resistance of rivets, 108
to, 106
strain on rivets, 226
She«t brass, weight of, 124, 130
glass, thickness of, 77
, weight of, 77
iron, weight of, 1-24
lead, covering power of, 06
, usual thickness, 80
weight of, SO
j Slate nails, zinc, 79 Slates good, to judge, 79
- laying. 7S
— sizes and weights, 79
- to test, 79 weights and sizes, 79
zinc, weight of, 96
Sheds for purifiers, 197 Shrinkage of castings, 09 Side plates, strains on, 225
sheets of gasholders, thickness of, 212
• purifier covers, 201
Siemens producer gas, 400 Simple sulphate plant, 404 Single lift gasholders, 210 Site for gasworks, 151 Six-hour charges, 238 Size and weight of slates, 79
of brickwork materials, 67
chimney for boilers, 178
— connections in works, 102
drawing paper, 59
flues, 158
holders in works, 210
internal pipe fittings, 309
mouthpieces, 155
photometer rooms, 358
purifiers, 197
rivets for boiler plates, I7f>
plates, 106
sand in mortar, 73
service pipes, 293
stables, 146
Slabs, paving, 74
Slaked lime, weight of, 272 Slaking coke, 244
lime before use, 271
increases bulk, 271
• , water required, 201
Slate nails, galvanised, 90 , lead, 90
Sleepers under mains, •_'!>! Sliding candle photometers, 300 Sloping retorts, carbon in, 247 Slow condensation, 104 Slopes of earths, C.2, 202 Smith's forge, air in, 229 Smooth surfaces to retorts, 155 Snow, allowance for on roofs, 79
- , pressure of, on gasholders, 214
- , weight of, 214 Soap for testing joints, 292 Socket joints, dimensions of, 2S9 Sockets, weight of, 290 Sodium carlH>nate, normal, 345
- names, 357
- hydrate, normal, 345 Solar distillate, ;i','6 Soldering, Hux for, 124 Solids, melting points of, 3:: I
- , power of for conducing heat, 338 Soot from coal tires, 317 Sound, speed of, SS
- in air, 323 Space above fuel, 155
- around retorts, 154
- between bearings for shafts, 183
fire bars, 155
for machine stoking, 153
occupied bv coals, 145
: for fuel, 200
Spaces, volume of, in concrete, 74 Specific heat, 88
of air, 241
bodies, 330
tire-clay, 152
metals, 334
346
-gravity of bricks, 69
compared with Twaddel,
- of benzene, 3SS
— caking coal, 2->2
— carbide, ;;«,»!
— coal to obtain, ;:>0
— elements, 322
— gases to obtain, 354,
— ten per cent, sic id, 375
— water gas, 352 per hour, 237
Speed of condensation, lt'>4
cutting tools, 223
sound, 88
in air, 32$
, safe of flywheels, 1>7
Spent oxide, analysis of, 269
, testing, 373
, value of, 2i'>'.»
Spermaceti for candles, 301 Sperm light of oil, 4u2 , value of gas in, 380
INDEX.
449
Sphere, volnrae of, 41
, wind pressure on, 219
Spiral gasholder guides, 220 Spoiling gas with too much air in purifi- cation, 275
Spontaneous combustion, 326 Square measure, 43
of a number, 41
roots, 1
Squares, 1
Stability of gas with benzol, 387
hydrocarbons, 325
inner lifts, 224
snlphided lime, 274
Stabling, 146
Stacking coal, 231
coke, 232
Staircases, treads and risers, 80 Standard burner of Gas Referees, 422
candles, 360
, Carcel, 370
, Hefner- Alteneck's, 370
liquor solution, 343
Standards, bending moment of, 22S
, distortion of, 223
, latticed, resistance of, 273
, strength of, 220
• , web plate, resistance of, 223
Starting gas engines, 193 Station meters, capacities of, 229
dimensions, 230
drums, 230
groaning, 319
• rate of working, 229
Stays to inner lifts, 211 Steadiness of holders, 220 Steam condensation of, 182
engine, calorific power developed.
191
mechanical efficiency of,
, water consumption in, 261
• for ejecting tar, 242
— M-anning, 315
• in lutes, 224
— purifiers, 275 •jacketing, saving by, 166
• pipes, expansion in, 182
- for boiler, 182
-, thickness of, 182 pressure for water gas, 393 required for producer, 243
in Dowson producer, 401
tubing, weight of, 297 under bars Of settings, 243
Steatite for burning tips, 308 Steel curbs for gasholders, 211
cylinders, strength of, 171
effect of heat on, 114
joists, breaking weight on, 138
tanks, 203
, testing, 112
Steps, stone, 81 Stiffeners, vertical, 211
Stills for sulphate making, 404 Stockramming, 205
G.E.
Stoking boilers, 260 Stone, Bath, weight of, 76
pillars, 69
, porosity of, 76
steps, 81
work, joints in, 76
,York, weight of, 76
Stones, resistance to crushing, Stopped pipes, to prevent, 246 Stopping gas engines, 193 Storage for coals, 145
, loss by, 279
. of materials, 145
Stores, coal, 145 Storing materials, 231 oils, 232
Stourbridge fire-clay, 152
Strains in gasholders, Wyatt's rules, 225
ropes, 112
on crowns with different rises, 213
side plates, 225
top sheets of gasholders, 210,
211
Strength, breaking, 101
, comparative, of metals, 130
, elastic, 101
, transverse of plates, 140
of a man, 228
belting, 188
boilers, 173 bolts, 103 brick columns, 68 cement and sand, 72 chains, 109 concrete, 75 cylindrical beams, 222 double headed rails, 131 English bond, 72 flat plates, 143 gasholder columns, 222 joints, 225
guide framing, 220
manilla rope gearing, 189
mortar, 72
rivets, 105
. riveted joints to plates, 107 . ropes, 109
• round rods, 130
• steel cylinders, 171
• tank walls, to calculate, 207 T-iron, 142
timber, 82
wrought-iron cylinders. 171 in gasholders,
220
Stresses safe on metals, 128 Strontium flames, 357 Struts in gasholder framing, 224 of angle iron or steel, 140
T-iron or steel, 140
Stucco, mixture for, 73 Suction pipes for pumps, 184 Sudden cooling of gas, 256 Sugg's burners, 369
Sulphate, amount from liquor, 404
• as manure, 406
O O
450
INDEX.
Sulphate from coal, 404
made in 1894, 405
plant condensers, 404
, fuel required, 405
, purifiers, 404
-, simple, 404
405
- of iron, 373
-, time required to manufacture,
Sulphide from hot lime, 274
of lime, 373
Sulphided lime, air with, 273
purifiers, action in, 273
, effect of CO2
upon, 273
upon, 273
H2S
stability of, 274
396
Sulphocyanic acid, 277
Sulphur compounds from water gas,
, oxidation of, 274
, quantity from coal,
273
removal of, 272 temperature of for-
mation, 244
from damp coal, 233
gas burning, 308 in coal, 382 , estimating, 381
— enrichers, 386
— gas, 267, 382
lost in lime purifiers, 271 passing to purifiers, 269
Sulphuretted hydrogen, 267
, test for, 375
Sulphuric acid for hydrocarbons, 345
, normal, 345
, to make, 405
Sumpts for tanks, 202 Superficial measure, 43 Superheated steam, 394 Superheaters for boilers, 176
' water gas, 393
Supply pipes to Argand burners, 308 Supporting hydraulic main, 159 Surface, heat lost by, 339
in scrubbers, 195
Surveying measure, 43 Symbols of elements, 322
T
ABLE of lighting, 309
— pressures of water against a vertical plane, 206 Table photometer, the, 425 Tabular numbers, correcting by (diagram), 368
, diagram of, 366
Tangential rollers, effect of, 211 Tank notes, 203 — sumpts, 202
wall, backings, 204
walls, 202
, hoop iron in, 205
>=— , pressures on, 203
Tank walls, rendering, 209
, resistance of weight of, 203
, thickness at base, 205
of, 203
Tanks, asphalte for, 209
, brick, 205
, details of, 209
, hoops to, 205
for gasholders, 202
, foundations for, 202
, leaks in, 205
for liquor and tar, 165
, sides, pressures of water on, 206
, rules for thickness of cylinder, 20i>
, to calculate strength of walls, 207
•, wrought iron, thickness of (dia-
gram), 208 Tar, analysis of, 407 , oil gas, analysis of, 396
and liquor tanks, area of, 165
as fuel, 244
, average yield of, 407
, carbonisation of, 251
, composition of, 407
concrete for footpaths, 146
proportions of, 318
constituents, 406
-^— distillates, 406
distilling, results of, 407
firing, advantages of, 242
for painting, 280
from caking coal, 407
pavements, 317
, gas from, by Peebles process, 402
, heat required to gasify, 402
, illuminating compounds in, 252
in hydraulic main, 253
scrubbers, 263
on coals for carbonising, 402
process at Widnes, 252
, products of, 381
, removal of, 164, 255
required to carbonise coal, 242
, salts in, 235
seal, gas washed by, 253
separating by friction, 159
, steam for injecting, 242
tanks, 165
used to fire retorts, 239
, yield of gas from, 252
Tees, flanged, dimensions of, 118 Tee iron, strength of, 142
or steel struts, 140
Teeth of wheels, proportions of, 187 Temperature below ground, 66
best in condensers, 255
, correcting for, 365
— for vapourising benzol, 387
— in ascension pipes, 247, 254
condensers, 254
cylinders, 168
— - flues, 154
foul main, 160, 254
generators, 393
- hydraiilic main, 251 — in purifiers, 275
INDEX.
451
Temperature retorts, 254
rooms, 308
saturator, 405
394
pounds, 244
carl ions, 233 373
301
of Bunsen flames, 357
— changes in flames, 353
— combustion of gases, 332
— decomposition of water,
formation of sulphur corn- gas entering purifiers, 268 flames, 354 fusion, 250 production of
hydro- revivification of oxide
— volatilisation of benzol
— water in scrubbers, 262
to convert fuel to CO, 240
Temperatures, colours of different, 248
, in flues, 236
gas engines, 191
mains, 300
settings, 241
, to estimate, 249
Ten-candle Pentane lamp, 423 Tensile strain on side plates, 225 tank sides, 205
strength of mortar, 72
Tension, expansion of iron by, 213 of ammonia gas, 263
aqueous vapour, 326
belts, 188
Testing benzene, 389 , carburetting for, 370
coal, 381
for acetylene, 378
gas liquor for CO.2, 374
with Argand burners, 367
iron and steel, 112
joints with soap, 292
lime, 372
mains in district, 291
pipes, 288
slates, 79
spent oxide, 373
valves, 292
white lead, 77
Test for CO-2, 378 H2S, 375
Tests for napthalene, 256
of axles, 149
coals, 251.
fire-bricks, 153
Theory of formation of flames, 312
light, 354
photometers, 358
Thermal efficiency of gas engines, 166
oil engines, 194
— steam engines, 166
unit, 166, 340
Thickness at base of tank Avails, 205
— (if ascension pipes, 159 CTOAVU sheets, 22G
Thickness of cylinder in tanks, 205
engine cylinders, 168
hydraulic cylinders, 151
layers in purifiers, 201
pipes for high pressures, 289
sheet lead, 80
glass, 77
sheets of wrought-irou tanks
(diagram), 208
side sheets of gasholders, 212
steam pipes, 182
tank walls, 402
tin plates, 96
walls, 72
web plates for girders, 139
wrought-iron pipes, 131
Threads for bolts, Whitworth, 126 gas pipes, 298
screAV, 125
Three lift gasholders, 210 Through retorts, 155 Tie-rods in coal stores, 146
, proportions of, 142
to benches, 154
Timber, 81
joists, 82
, safe load on, 86
, preserving, 81
, safe load on, 82
, seasoning, 81
, strength of, 82
Time of contact in purifiers, 197
required for seasoning timber, 83
= to charge, 246
make sulphate, 405
to start water gas plant, 394
Tin plates, thickness of, 96
tubes, weight of, 124
To estimate furnace efficiency, 155
— save fuel, 241
— test heats in water gas plant, 393 Ton, decimals of, 49
Too much air in purification, 274 Top sheets of gasholders, strains on, 210 Torsion, resistance to, 107 Tower scrubbers, 195
, effect of cold on, 262
Toxicity of acetylene, 391 Traction resistance on roads, 147 force of locomotives, 148
Trains, resistance of, 149 Tramcars, gas engines for, 192 Tramways on roads, 147 Trap sand for mortar, 73 Transmission of gas through pipes, 300 heat, 175
Transverse strength of plates, 140 Travel in flues, 157 Treads and risers to staircases, 80 Triangles in guide framing, 220 Trigonometrical terms, 41 Troy weight, 42 Trunk mains, 292 Trussed holder curbs, 210 Trussing gasholders, 212 Tubes, block tin, weight of, 124
452
INDEX.
V
Tuck pointing, 74
Turned and bored pipes, advantages of, 292
, dimensions of,
200
Turmeric paper, to make, 342
Twaddel, 264
, compared with specific gravity,
I 346
I , to reduce to ounce strength, 264
TTNACCOUNTED for gas, 301 U Uneven charging, 233 Unions for gas meters, 320 Unit of heat, 166 Uniting lead, 97 Units, electric, 89
of light, Harcourt's, 369
Unloading materials, 145 Use of Portland cement, 73
sand in mortar, 72
ACUUM in chimneys, 159
te gas flues, 241 Value of acetylene, 390
chalk, 270
explosive mixtures, 193 J^
gas in sperm, 380
spent oxide. 269
Values of different quality gases for eva- porating, 356
gases for lighting and heating,
356
motive power, 194
Valves, boxing round in works, 165 , dimensions of, 293
for hydraulic mains, 161
in purifier house, 201
, safety, 176 >
— — to condensers, 164
, testing, 292
Van Steenberg's process, 399 Vaporising benzol, temperature for, 387 Vapour tension of benzene, 387 Varnish, covering power of, 77 Velocity in exhaust pipes, 182
steam pipes, 182
of diffusion, 279
gases in chimneys, 179
retorts, 234
WALLS for coal stores, 146 of settings, 154
tanks, 202
, thickness of, 72
to fronts of benches, 155
Warming by steam, 315
secondary air, 158
Washers and scrubbers, 195
for petroleum pipes, 397
, pressures thrown by, 196
, proportions of, 102
-, weight of, 103
Washing and scrubbing, 262
gas with mineral oil, 325
Waste gases, reduction in temperature of,
243 Water, absorptive power of, 374
, acetylene absorbed by, 391
and producer gas mixed, 398
consumption in steam engines,
261
distribution in scrubbers, 195 evaporated by fuels, 259
furnaces, 155, 243
-, evaporation of, 332
-, expansion and weight of, 333
of when freezing, 337
light, 356 water, 151 wind, 216
Ventilating flue, chimney as, 308 Ventilation notes, 311
of coals, 145
photometer rooms, 358
retort houses, 154
Vertical sheer on standards, 224
stiffeners, 211
Visibility of lights at distances, 310 Vitiation of air by acetylene, benzene, ethylene, marsh gas, 355
lights, 305
Volume of one pound of air, 327 sphere, 41
fall, power of, 88
for condensing water gas,
from carbon, 394
gas analysis, 392, 395
, blast mains for, 393
, blowers for, 393
, CO2 in, 394
carburettor, 393
, composition of, 351
condenser, 393
, cost of, 399
, enriching value of, 396
, fuel required for, 394
generator, 393
, oil required for, 394
plant, explosions in, 394
, lighting up, 394
, men required for, 393
, time to start, 394
-, to test heats in, 393
production, equation of, 398
purification, 396
scrubber, 393
, steam pressure for, 393
, sulphur compounds in, 396
superheater, 393
with anthracite coal, 398
heated through plates, 317
in ash-pans, 243
hydraulic mains, 253
lime, 271
oil gas tar, 396
oxid-3, 267
scrubber, temperature of, 262
mixing at different heats, 339
, pounds heated by gases, 331
various sub-
stances, 331 , power of absorption, 196
|
INI Water, pressure of, 299, 323 |
)EX. 453 Weight of sheet glass, 77 iron, 124 |
|
COJUlJlll^ UI , ^ -i |
|
|
192 |
sockets 290 |
|
... -to slikc coke °11 |
washers, 103 water 3°3 |
|
velocity of 151 |
|
|
Water-logged earth backing, 203 Watertight concrete, 207 Water-tube boilers, coke fired, 175 |
|
|
Weights and measures, 42 |
|
|
Water-tubing, weight of, 297 Watts, electric, 89 Web plates for girders, 139 Wedgewood's pyrometers, 248 Weight, loss of, by stacking coal, 231 |
Weldon mud, analysis of, 274 |
|
compai cd **"* °^J^C> u ' ^ |
|
|
Wet coal causes napthalene, 256 lime for purifying, 271 |
|
|
Wetted surface in standard washers, 262 Wetting material in scrubbers, 262 oxide with ainmoiiiacal liquor. 275 Wicks of standard candles, 360 Wide furnaces, 242 Width of belts, 190 |
|
|
bell of holder 91° |
|
|
bolt heads, 102 |
|
|
. > ^' |
|
|
Widths of rims of pulleys, 187 Willesden roofing, 80 * Wind allowance on roofs, 79 |
|
|
composite pipe, 123 copper nails, 97 |
|
|
on chimneys, 179 |
|
|
— earths, 62 frit SO |
|
|
fire-bricks 63 |
|
|
, velocity of, 21(3 Wire gauges in decimals of l inch, 89 Wire ropes on pulleys, 232 |
|
|
Wheels, proportions of teeth, 187 White lead, 77 |
|
|
hoop iron, 127 |
|
|
Whitworth threads for screws, 125 |
|
|
Wood changing to coal, 381 charcoal, gas from, 252 |
|
|
Wooden joists, 137 |
|
|
Work of bricklayer, 72 Workshop area, 228 |
|
|
rivet heads, 106 |
|
|
Works mains in wrought iron, 165 Wrought-iron bridges, weight of, 141 |
|
|
sheet brass, 124, 130 |
454
INDEX.
Wrought-iron cylinders, strength of, 171
|
*V!.Hf ?111<pl v ".oco |
|
|
- pipe thicknesses, 131 |
^a^ irpm tar, ^ |
|
wiLii exnaUuici, lo7 |
|
|
gram), 208 |
|
|
per cent., ^oo |
|
|
works mains, 165 Wyatt's rales for strains in gasholders, 225 T^ARN, depth of, in pipe joints, 292 |
square foot of retorts, 234 York paving, weight of, 76 stone, weight of, 76 ZINC sheeting, weight of, 96 slating nails, 79 |
|
Year, decimals of, 47 |
THK END.
BBADBUBY, AGNEW.. & CO. LD., PB1NTEBS, LONDON AND TONBBIDGE.
ADVERTISEMENTS.
MlLN€'S PAT6NT
COMPOSITE DRY GAS METER.
Cast Iron Body. Brass Side Tubes. Top Portion of Extra Thick Tin Plate.
Weight not unduly Increased. Specially useful in Damp Situations. As easily Examined and Repaired as an ordinary Tin Plate Dry Meter.
Makers of all kinds of QAS TESTING APPARATUS, including O'CONNOR'S Patent Test Meter and Patent Pressure Indicator.
JAMES MILNE & Son, Ltd.
"MILNE, EDINBURGH.'
TELEGRAMS:
* Milton House Works.
"MILNE, LONDON." "GASLIGHTS, GLASGOW." "MILNE, LEEDS."
§0, HOLBORN VIADUCT, E.G. 111, ST. VINCENT STREET. 28, WELLINGTON STREET.
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