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DATA  SHEETS 


REVISED  AND  RE-ARRANGED  IN  LIBRARY  FORM 


r- 

c\j 

00 


o 


No.  7 


Shafting,  Keys  and 
Keyways 


PRICE  25  CENTS 


CONTENTS 

Horsepower  Transmitted  by  Shafting 4 

Diagrams  of  Strength  of  Shafts  for  Different  Fiber  Stresses 8 

Moment  of  Inertia  and  Section  Modulus  of  Circular  Sections 12 

Shear  Stresses  Combined  with  Tension  or  Compression  Stresses 13 

Combined  Bending  and  Torsional  Moments 14 

Tables  of  Diameters  of  Shafts  for  Combined  Torsional  and  Bending 

Stresses  18 

Diagrams  of  Diameters  of  Shafts  for  Combined  Torsional  and  Bending 

Stresses  20 

Weights  and  Areas  of  Cold  Rolled  Steel  Shafting 25 

Allowances  and  Tolerances  for  Running  Fits 27 

Allowances  for  Forcing,  Driving  and  Running  Fits ".28 

Pressure  Factors  for  Forcing  Fits 29 

Limits  for  Limit  Gages 30 

Woodruff  Keys 32 

United  States  Navy  Standard  Proportions  of  Keys 35 

Table  of  Gib  Keys 36 

Table  for  Milling  Keyways 37 

Duplex  Keys 38 

The  Industrial  Press,  49-55  Lafayette  Street,  New  York 
Publishers  of  MACHINERY 

COPYRIGHT,    1910,   THE   INDUSTRIAL    PRESS,    NEW  YORK 


MACHINERY'S  DATA  SHEET  SERIES 


COMPILED  FROM  MACHINERY'S  MONTHLY  DATA 

SHEETS  AND  ARRANGED  WITH 

EXPLANATORY  MATTER 


No.  7 


Shafting,  Keys  and 
Key  ways 


CONTENTS 

Horsepower  Transmitted  by  Shafting 4 

Diagrams  of  Strength  of  Shafts  for  Different  Fiber  Stresses 8 

Moment  of  Inertia  and  Section  Modulus  of  Circular  Sections 12 

Shear  Stresses  Combined  with  Tension  or  Compression  Stresses 13 

Combined  Bending  and  Torsional  Moments 14 

Tables  of  Diameters  of  Shafts  for  Combined  Torsional  and  Bending 

Stresses  18 

Diagrams  of  Diameters  of  Shafts  for  Combined  Torsional  and  Bending 

Stresses  20 

Weights  and  Areas  of  Cold  Rolled  Steel  Shafting 25 

Allowances  and  Tolerances  for  Running  Fits 27 

Allowances  for  Forcing,  Driving  and  Running  Fits 28 

Pressure  Factors  for  Forcing  Fits 29 

Limits  for  Limit  Gages 30 

Woodruff  Keys 32 

United  States  Navy  Standard  Proportions  of  Keys 35 

Table  of  Gib  Keys i  ^-.*  :.. .; ;  .\  • ',  1 36 

Table  for  Milling  Key  ways '.«.•".  ..'.'.* .  X  .' .V.  .* 37 

Duplex  Keys. .  .  .38 


Copyright,  1930,  The  Industrial  Tress,  Publishers  of  MACHINERY, 
49-55  Lafayette  Street,  New  York  City 


In  the  following  pages  are  compiled  a  number  of  diagrams  and  con- 
cise tables  relating  to  shafting,  keys  and  keyways,  carefully  selected 
from  MACHINERY'S  monthly  Data  Sheets,  issued  as  supplements  to  the 
Engineering  and  Railway  editions  of  MACHINERY  since  September,  1898. 
A  number  of  additional  tables  also  are  included  which  are  published 
here  for  the  first  time. 

In  order  to  enhance  the  value  of  the  tables  and  diagrams,  brief  ex- 
planatory notes  have  been  provided  wherever  necessary.  In  these 
notes  references  are  made  to  articles  which  have  appeared  in  MA- 
CHINERY, and  to  matter  published  in  MACHINERY'S  Reference  Series, 
giving  additional  information  on  the  subject.  These  references  will 
be  of  considerable  value  to  readers  who  wish  to  make  a  more  thorough 
study  of  the  subject.  In  a  note  at  the  foot  of  the  tables  reference  is 
made  to  the  page  on  which  the  explanatory  note  relating  to  the  table 
appears. 


•A       •.,,"•;«?; 

J  «.•»  i»     «•    •>.*  %  . 


SHAFTING,  KEYS  AND  KEYWAYS 


Horsepower  Transmitted  by 
Shafting 

A  question  which  often  meets  the  ma- 
chine designer  is  that  of  determining 
the  horsepower  that  may  be  safely  trans- 
mitted by  a  shaft  of  a  given  diameter  at 
a  given  number  of  revolutions  per  min- 
ute. Quite  as  frequently  the  horsepower 
and  the  speed  are  known,  and  it  is  re- 
quired to  find  the  diameter  of  the  shaft 
which  will  safely  transmit  the  given 
power.  On  page  4  a  table  is  presented 
giving  working  proportions  for  shafting 
of  medium  steel;  this  table  will  be 
found  useful  whenever  either  of  the 
above  problems  are  met  with. 

Assume,  for  example,  that  it  is  re- 
quired to  find  the  diameter  of  a  shaft 
for  transmitting  40  horsepower  at  a 
speed  of  250  revolutions  per  minute.  The 
shaft  is  not  subjected  to  any  bending 
action  except  its  own  weight.  Consult- 
ing the  table  to  the  left  on  page  4  and 
locating  40  in  the  body  of  the  table,  in 
the  column  under  250  revolutions  per 
minute,  we  find  in  the  extreme  left-hand 
column  that  the  diameter  of  the  re- 
quired shaft  should  be  two  inches.  The 
table  also  gives  the  maximum  permis- 
sible distance  between  the  shaft  bear- 
ings, which  in  this  case  is  slightly  more 
than  14  feet. 

When  the  exact  horsepower  given  can- 
not be  found  in  the  table,  it  is  advisable 
to  take  the  nearest  larger  value  listed 
in  the  table,  and  find  the  diameter  of 
shaft  required  to  transmit  this  horse- 
power. 

On  page  5  a  table  is  given  for  finding 
the  horsepower  which  can  be  safely 
transmitted  by  cold  rolled  steel  line 
shafting.  The  body  of  the  table  gives 
the  horsepower.  For  example,  assume 
that  a  3-inch  shaft  revolves  at  a  speed 


of  400  revolutions  per  minute.  What 
power  can  this  shaft  safely  transmit? 
By  locating  3  inches  in  the  left-hand 
column,  and  400  at  the  top  of  the  verti- 
cal columns  at  the  head  of  the  page, 
and  following  the  vertical  column  down- 
ward until  opposite  3  inches,  we  find 
that  under  the  given  conditions  154 
horsepower  may  be  safely  transmitted. 

On  pages  6  and  7  are  given  the  horse- 
power which  may  safely  be  transmitted 
by  turned  steel  line  shafting.  In  this 
case  the  diameters  are  carried  up  to  12 
inches.  The  tables  on  pages  5,  6  and  7 
are  used  by  the  transmission  depart- 
ment of  the  Jones  &  Laughlin  Steel  Co. 
These  tables  are  based  on  the  assump- 
tion that  bearings  are  placed  at  inter- 
vals of  from  8  to  10  feet,  and  that  all 
pulleys  are  located  near  the  bearings. 
The  reason  why  the  table  for  cold-rolled 
steel  shafting  is  carried  up  only  to  5 
inches  diameter,  is  that  5  inches  is  the 
largest  diameter  cold  rolled  at  the  pres- 
ent time. 

Diagrams  for  Strength  of 
Bound  Shafts 

On  pages  8  to  11,  inclusive,  are  given 
diagrams  for  determining  the  dimen- 
sions of  round  shafts  under  different  con- 
ditions. The  diagram  on  page  8  is 
intended  for  finding  the  diameter  of  the 
shaft  when  the  twisting  moment  and 
the  fiber  stress  are  known.  Assume  as 
an  example  that  a  shaft  is  subjected  to 
a  twisting  moment  of  100,000  inch- 
pounds,  and  that  the  allowable  fiber 
stress  is  8000  pounds  per  square  inch. 
The  twisting  moments,  in  thousands  of 
inch-pounds,  are  given  on  the  scale 
at  the  bottom  of  the  table,  and  the  fiber 
stresses  are  represented  by  the  diagonal 
(Continued  on  page  16.) 


347498 


4  MACHINERY'S  DATA  SHEETS 


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No.  7  SHAFTING,  KEYS  AND  KEY  WAYS  5 

HORSEPOWER  TRANSMITTED  BY  COLD  ROLLED  STEEL  LINE  SHAFTING 


Diameter 
of  Shaft 

Number  of  Revolutions  Per  Minis  fe 

100 

125 

150 

175 

200 

225 

250 

275 

300 

325 

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Contributed   by   Frank   Wackermann,    Pittsburg.    Pa.     Explanatory   note  :      1'ajje   3. 


6  MACHINERY'S  DATA  SHEETS  No.  7 

HORSEPOWER    TRANSMITTED    BY    TURNED    STEEL     LINE    SHAFTING 


Diameter 
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Number  of-  Revolutions  Per  Minute 

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165 

193 

220 

247 

275 

302 

330 

358 

385 

440 

495 

S5O 

60S 

660 

4% 

1  19 

149 

179 

209 

238 

266 

298 

327 

357 

396 

416 

476 

S3  7 

595 

bS4 

7/4 

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129 

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193 

226 

258 

290 

322 

355 

387 

420 

452 

516 

581 

646 

7/0 

775 

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139 

174 

208 

244 

278 

313 

347 

382 

417 

452 

486 

557 

625 

695 

765 

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Contributed  by  Frnnk  Wackermann,   Plttsburg,   Pa.     Explanatory   note  :     Page  3. 


No.  7  SHAFTING',  KEYS  AND  KEY  WAYS  1 

HORSEPOWER    TRANSMITTED    BY    TURNED    STEEL    LINE    SHAFTING 


Diameter 
of  Shaft 

A/umber  of  Revolutions  Per  Minute 

100 

125 

ISO 

17  £ 

200 

225 

250 

27  S 

300 

325 

35O 

400 

450 

£00 

550 

600 

£§ 

ISO 

187 

225 

262 

300 

337 

375 

412 

450 

487 

525 

6OO 

675 

750 

825 

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161 

201 

242 

281 

322 

362 

403 

443 

483 

523 

564 

644 

725 

80S 

886 

966 

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172 

215 

259 

301 

344 

387 

430 

473 

5/6 

559 

602 

689 

775 

861 

947 

1033 

^ 

184 

230 

277 

322 

369 

415 

461 

507 

S53 

599 

645 

738 

830 

922 

10/4 

//oe 

ff 

197 

247 

297 

345 

395 

445 

495 

545 

593 

642 

692 

791 

890 

989 

/088 

1/86 

5 

211 

264 

317 

369 

422 

475 

S28 

581 

633 

686 

739 

844 

950 

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225 

282 

339 

394 

451 

507 

S64 

621 

677 

733 

789 

902 

10/5 

1/28 

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1353 

0 

240 

300 

360 

419 

4-80 

S40 

600 

66t 

720 

780 

840 

960 

IO8O 

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255 

320 

384 

446 

5"  II 

575 

639 

704 

766 

830 

894 

1022 

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271 

339 

407 

473 

542 

610 

678 

747 

813 

881 

949 

1084 

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257 

360 

432 

502 

575 

647 

72O 

792 

863 

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382 

459 

535 

6/1 

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764 

841 

917 

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1528 

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322 

403 

484 

564 

644 

725 

806 

887 

960 

1047 

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341 

427 

513 

598 

682 

767 

853 

939 

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0% 

361 

452 

543 

632 

722 

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903 

994 

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1444 

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381 

476 

573 

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762 

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568 

712 

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1138 

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2076 

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623 

780 

937 

1094 

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1944 

2222 

2500 

2778 

3055 

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2393 

2692 

2994 

3295 

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3888 

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1285 

1608 

1934 

2258 

2573 

2895 

3219 

3543 

3860 

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2422 

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3/05 

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2966 

3380 

3802 

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2402 

2886 

3369 

3840 

432O 

4804 

5288 

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Contributed  by  Frank  Wackermann,   Pittsburg,   Pa.     Explanatory  note  :     Page  3. 


MACHINERY'S  DATA  SHEETS 


No.  7 


< 

0 

loo 

200 
800 
500 

1. 

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15 
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f  » 

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p.   90 

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No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


0 

200 
300 
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15 
20 

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§    100 
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175 
200 

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400 
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10 


MACHINERY'S  DATA  SHEETS 


No.  7 


o      i  1 


Bending  moments  in  thousand  inch  pounds. 

g  g  g  g  g§    &    g  y 


coo 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


11 


NEW  DIAMETERS  REQUIRED  FOR  SHAFTS. 


\m 


>m\ 


^ 


\\ 


\\ 


\ 


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ss 


\PI 


\ 


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when 
T 


meter  for 
No.  3. 


ain 


ds 


12  MACHINERY'S  DATA  SHEETS  No.  7 

MOMENT  OF  INERTIA  AND  SECTION  MODULUS  OF  CIRCULAR  SECTIONS 


Moment  of  /nerfia  I-  "gff*                  Secf/on  Moctu/us  Z-    ^5f~ 
O  «  Diameter  in  Inches.     J~-  Moment  of  /nerfia.        Z  -  Sect/on  Mocfis/e/s. 

D 

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0 

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6 

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4.4388 

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0.374S 

3% 

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4.9226 

8 

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SO.  265" 

1 

0.3423 

0.4213 

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S./772 

8k 

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0.  3980 

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4 

256.24 

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0.5846 

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322.00 

7/.f09 

4 

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4 

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6.2832 

4 

359.37 

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2 

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Contributed  by  John  S.  Myers,  MACHINERY'S  Data  Sheet  No.  87.     Explanatory  note:     Page  16. 


No.  7  SHAFTING,  KEYS  AND  KEYWAYS  13 

SHEAR  STRESSES  COMBINED  WITH   TENSION   OR  COMPRESSION   STRESSES 


Let  £  -  Un/f  Shear,  t  -  Vn/f  Tens/on  or  Compress  /'on, 
5m  -  Max  /mum  Combmed  Vn/'f  Shear, 
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Factor    3 

1 

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/.37/9 

f.45 

2.  03  3  & 

/.0573 

/.45 

/.  2352 

/.35~/3 

f.SC 

Z.OQlf 

/.054/ 

/.S'O 

/.  2.50O 

/.3333 

Contributed  by  John  S.  Myers,  MACHINERY'S  Data  Sheet  No.  87.     Explanatory  note  :     Page  IT. 


14 


MACHINERY'S  DATA  SHEETS 


No.  7 


3enctmg  Moments  /n  Incn  Pounds  —  Av 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


15 


Bencff'ng  Momertte  //?  /nch  Pounds  — 


SI 


nil 


8* 

1 


gw 

So! 


I. 


l! 


££ 


ir 


^ 


! 


16 


MACHINERY'S  DATA  SHEETS 


No.  7 


lines.  Locate,  therefore,  100  on  the 
lower  scale,  and  follow  the  line  from 
the  point  so  located  upward  until  inter- 
secting the  diagonal  line  marked  8000. 
From  the  point  of  intersection  follow 
the  horizontal  line  to  the  scale  at  the 
left-hand  side  marked  "Diameter  of  bar 
in  inches."  It  will  be  seen  that  a  shaft  4 
inches  in  diameter  is  required. 

On  page  9  is  given  a  diagram  of 
transverse  strength  of  round  shafts  for 
different  fiber  stresses.  Assume  in  this 
case  that  a  shaft  is  subjected  to  a  bend- 
ing moment  of  80,000  inch-pounds  and 
that  a  fiber  stress  of  12,500  pounds  per 
square  inch  is  allowable.  The  bending 
moments  in  thousands  of  inch-pounds 
are  given  on  the  scale  at  the  bottom  of 
the  diagram,  and  the  fiber  stresses  are 
represented  by  the  diagonal  lines,  the 
same  as  in  the  previous  diagram;  hence 
by  locating  80  on  the  lower  scale  and 
following  the  vertical  line  from  the 
point  so  located  until  it  intersects  the 
diagonal  line  marked  12,500,  and  from 
the  point  of  intersection  following  the 
horizontal  line  to  the  left,  we  find  that 
the  diameter  of  the  required  shaft  is  4 
inches. 

On  page  10  is  given  a  diagram  for 
the  strength  of  round  shafts  subjected 
to  a  combined  twisting  and  bending  mo- 
ment.   This  diagram  is  calculated  for  a 
tensile  strength  of  7500,  and  a  torsional 
shearing  strength   of   6000   pounds   per 
square  inch.     The  twisting  moment  in 
thousands  of  inch-pounds  is  located  on 
the  scale  at  the  bottom  of  the  diagram, 
the  bending  moments  are  located  on  the 
scale  at  the  left-hand  side,  and  the  di- 
ameter of  the  required  shaft  is  deter- 
mined by  the  curve  which  comes  nearest 
to  the  intersection  between  the  vertical 
line  from  the  twisting  moment  and  the 
horizontal   line   from   the   bending   mo- 
ment.   Assume,  as  an  example,  that  a 
shaft   is    subjected    to   a    twisting   mo- 
ment of  175,000  inch-pounds  and  a  bend- 
ing moment  of  90,000  inch-pounds.    The 
two  lines  corresponding  to  these  values 
are  found  to  intersect  very  nearly  on 


the  6-inch  curve.    A  shaft  6  inches  in 
diameter  is  thus  required. 

On  page  11  an  auxiliary  diagram  to 
that  on  page  10  is  given,  from  which 
the  required  diameter  of  round  shafts 
may  be  found  for  other  fiber  stresses 
than  7500  pounds  per  square  inch,  for 
which  the  diagram  on  page  10  is  made 
up.  When  using  this  table,  the  diam- 
eter for  a  fiber  stress  is  7500  pounds 
per  square  inch  is  first  found  from  page 

10.  This   diameter   is   then   located  on 
the  lower  scale  in  the  diagram  on  page 

11.  The   vertical   line   from   the   point 
so  located  is  followed  until  it  intersects 
the  diagonal  line  representing  the  allow- 
able fiber  stress;   from  the  point  of  in- 
tersection a  horizontal  line  is  then  fol- 
lowed to  the  left-hand  scale,  where  the 
corrected  diameter  for  the  permissible 
fiber  stress   is   read   off.    For   example, 
if  we  have  found  from  the  diagram  on 
page  10  that  for  given  conditions  a  six- 
inch  shaft  is  required  at  a  fiber  stress 
of    7500    pounds    per    square    inch,    we 
find  from  this  diagram  that  if  we  in- 
crease  the   stress   to   12,500   pounds,   a 
shaft   5    inches    in   diameter   would   be 
sufficient.         [MACHINERY,      September, 
1905,  Computing  Hollow  and  Solid  Shaft- 
ing.] 

Moment  of  Inertia  and  Section  Modulus 
of  Circular  Sections 

When  calculating  the  strength  of  shaft- 
ing, tables  of  the  moment  of  inertia  and 
section  modulus  of  circular  sections,  for 
diameters  varying  by  small  fractions  of 
an  inch,  are  very  convenient.  On  page 
12  such  a  table  is  given.  The  values  in 
this  table  are  used  when  the  shaft  is 
subjected  to  bending  moments  only. 
For  torsional  moments  the  polar  mo- 
ment of  inertia  and  section  modulus 
should  be  used;  but  since  these  quanti- 
ties are,  in  this  specific  case,  exactly 
double  those  given  in  the  table,  the  tab- 
ulated values  may  simply  be  multiplied 
by  2  in  cases  where  torsional  moments 
are  dealt  with. 

The  use  of  the  table  can  be  best  illus- 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


17 


trated  by  an  actual  problem.  Assume 
that  the  maximum  combined  bending 
moments  on  a  shaft  are  52,900  inch- 
pounds.  Using  a  fiber  stress  not  ex- 
ceeding 10,000  pounds  per  square  inch, 
what  size  shaft  would  be  required?  The 
section  modulus  in  this  case  is 

52,900 

Z  = =  5.29. 

10,000 

Referring  now  to  the  table  on  page  12 
we  find  that  the  diameter  corresponding 
to  this  section  modulus  is  3 13/16 
inches,  approximately.  This  diameter 
corresponds  to  a  value  of  Z  =  5.44,  and 
is  thus  on  the  side  Of  safety.  [MACHIN- 
ERY, May,  1908,  Maximum  Stresses.] 

Shear  Stresses  Combined  with  Tension 
or  Compression  Stresses 

The  question  of  shearing  stresses  com- 
bined with  tension  or  compression 
stresses  is  one  which  always  causes  con- 
siderable difficulty.  On  page  13  a  table 
of  factors  is  given  by  means  of  which 
the  maximum  combined  unit  shear  and 
the  maximum  combined  unit  tension  or 
compression  may  be  determined  when 
the  forces  causing  shear  and  tension  or 
compression  are  known.  For  example, 
assume  that  8  (see  table  on  page  13)  = 
9000,  and  t  =  12,000  pounds  per  square 

8 

inch;  then  —  =  0.75,  and  from  the  table 
t 

we  find  that  the  tension  (or  compres- 
sion) factor  x  then  equals  1.40.  This 
means  that  if  the  shear  is  75  per  cent 
of  the  tension,  the  maximum  combined 
tension  will  be  1.40  times  what  it  would 
have  been  if  there  had  been  no  shear. 
This  table  makes  it  possible  to  quickly 
determine  the  maximum  stresses  in 
shafts  subjected  to  combined  tension  and 
compression  stresses,  provided  the  sep- 
arate unit  stresses  are  known.  [MA- 
CHINERY, March  and  April,  1904,  Notes 
on  Design;  May,  1908,  Maximum 
Stresses;  MACHINERY'S  Reference  Series 
No.  12,  Mathematics  of  Machine  Design, 
Chapter  I:  Machinery  Shafting.] 


Table  of  Combined.  Bending-  and 
Torsional  Moments 

One  of  the  most  familiar  examples  of 
combined  stresses  in  shafting  is  that  of 
torsion  and  bending,  the  torsional 
stresses  being  shearing  stresses,  and  the 
bending  stresses  being  tension  and  com- 
pression stresses.  The  maximum  stress 
may  be  found  by  calculating  each  separ- 
ately, and  combining  them  by  the  aid  of 
the  table  on  page  13,  as  already  men- 
tioned. The  tables  on  pages  14  and  15 
also  may  be  used  for  more  directly  com- 
bining these  stresses.  If  the  bend- 
ing and  the  torsional  moments,  both  in 
inch-pounds,  are  known,  they  are  located 
at  the  left-hand  side  and  at  the  top  of 
the  tables,  as  indicated.  The  body  of 
the  tables  then  gives  the  maximum  or 
"ideal"  torsional  moment  in  the  line 
marked  T  to  the  left,  and  the  maximum 
or  "ideal"  bending  moment  in  the  lines 
marked  B.  For  example,  a  shaft  3^ 
inches  in  diameter  is  subjected  to  a  tor- 
sional moment  of  36,000  inch-pounds  and 
a  bending  moment  of  35,000  inch-pounds. 
What  is  the  combined  shearing  stress 
and  the  combined  tension  and  compres- 
sion stress? 

Referring  to  the  table  on  page  15  and 
remembering  that  all  values  may  be  mul- 
tiplied by  10,  we  find,  by  locating  the 
torsional  moment  3600  (instead  of 
36,000)  at  the  top  of  the  column,  and 
the  bending  moment  3500  (instead  of 
35,000)  in  the  left-hand  column,  that  the 
maximum  twisting  moment,  in  this  case, 
is  50,210,  and  the  maximum  bending  mo- 
ment 85,210  inch-pounds.  Having  now 
found  the  maximum  moments,  we  can 
find  the  maximum  combined  unit  shear 
and  unit  tension  or  compression;  From 
page  12  we  find  tkat  the  section  modulus 
Z  for  a  3M»-inch  shaft  is  4.209.  The  polar 
section  modulus  being  twice  this,  we 
have  Zp  =8.418. 
Using  the  notation, 
Maximum  combined  unit  shear  =  Sm, 
Maximum  combined  unit  tension  or 
compression  =3  fm, 

(Continued  on  page  24.) 


18 


MACHINERY'S  DATA  SHEETS 


No. 


51 
U 

H 

U 
5Jt 

33 

3* 

^ 

p 

J» 

i 

8i 


Bending  Moments  in  Thousands  of  /ncn  Pounds. 


fe^fe 


&fcfe 


!S 


Qo 


(N 


!*** 


is 


Ui 


Ui 


N) 


Ui 


U| 


(M 


Ui 


Jo   N   f^ 


^  Q^N^lCi  **"•  ^  ^  ^  $Q  ^  ^tN| 


U| 


Bending  Moments  tn  Thousands  of  /nch  Pounds. 


"SI 

3 


re 


i? 


s 
s 
nc 


Hi 


Irf 

1 

ill 


ss 
nc 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


19 


Bend/'ngf  Women  fs  in  Thousands  of  /nch  Pounds. 


00 

to    <*   Si 


*0 


I 

« 


Qo 


NKfcc- 


Co 


Co 


^\VMQ^I 


Qo 


Co 


CO 


Co   Qo 


Qo 


Co 


CD 


Oo 


Qo 


Qo 


h) 


Qo 


Co 


Co 


Co 


Co 


Co 


Qo 


CD 


CD 


Co 


Qo 


Co 


Qo 


Qo 


"»1         ^1         /N 

^^   ^ 


Qo 


Qo 


Oo 


Co 


Co 


Co 


Qo 


Co 


Oo 


Qo 


r. 


«fo^«W*<^ 


20 


MACHINERY'S  DATA  SHEETS 


No.  7 


Momenfe  />?  Thousands  of  //7ch  fot/nc/s  -B. 


No.  7 


SHAFTING,  KEYS  AND  KEY  WAYS 


Bending  Moments  in  Ten   Thousands  of  fncn  Pounds. 


22 


MACHINERY'S  DATA  SHEETS 


Bending  Moments  in  Hundred  Thousands  of  fnch  Pounds. 


S*  toooo 
I 


1       I 


i    i    i 


I I 


I I 


II  I      I  I  I 


/   I  / 


/  I     I/ 


J I 


7 


A 


No.  7 


SHAFTING,  KEYS  AND  KEY  WAYS 


23 


Bending  Moments  in  Mi //ions  of  /nch   Pounds. 


I 


•  =7SOO 


I    I 


x 


t 


I    1 


z 


/G 


J_ 


I I 


T 


«r 


X 


it- 


j I 


x 


24 


MACHINERY'S  DATA  SHEETS 


No.  7 


and  proceeding  to  make  use  of  the 
values  found  in  the  table  on  page  15  we 
find: 

50,210 

fi£   = =5970,  and 

8.418 

85,210 

tm  =-     -  =  10,120. 
8.418 

These  two  values  give  the  maximum 
combined  unit  stresses. 

It  will  be  noted  that  in  the  tables  on 
pages  14  and  15  the  values  B  of  the 
maximum  or  ideal  bending  moments  are 
always  greater  than  the  values  T  of  the 
maximum  or  ideal  torsional  moments. 
Hence  it  is  the  combined  tension  or 
compression  stresses  which  determine 
the  size  of  the  section  to  be  used,  and 
the  maximum  torsional  moment  may  be 
entirely  neglected.  All  authorities  do 
not  agree  on  the  subject  of  combined 
torsion  and  bending.  The  tables  given 
agree  with  the  formulas  given  by  Ran- 
kine.  The  formula  given  by  Grashof 
gives  a  torsional  moment  which  has  a 
greater  value  than  that  obtained  from 
the  Rankine  formula.  This  latter,  how- 
ever, is  commonly  used,  and  shafting 
designed  from  calculations  based  upon 
this  formula  has  proved  satisfactory. 

In  this  connection  it  is  well  to  note 
that  in  the  case  of  shafting,  the  location 
and  direction  of  the  tooth  loads,  belt 
pulls,  etc.,  which  produce  bending,  re- 
main fixed  while  the  shaft  rotates.  The 
bending  stresses  are  thus  constantly 
varying  in  direction,  and  since  a  greater 
factor  of  safety  should  be  used  for  re- 
versible stresses  than  for  those  which 
are  constant  in  direction,  many  design- 
ers recommend  that  the  allowable  work- 
ing stresses  should  vary  according  to 
whether  the  torsional  or  bending  mo- 
ment predominates.  Higher  stresses 
may  be  used  when  the  torsional  mo- 
ment is  greater;  when  the  bending  mo- 
ment is  greater  the  stresses  ought  to  be 
made  proportionately  less.  On  the 
other  hand  the  ultimate  tensile  stress  is 
approximately  25  per  cent  greater  than 


the  ultimate  shearing  stress,  and  as  the 
determining  stress  is  always  the  com- 
bined tension  or  compression  and  not 
the  shear,  and  since  the  Rankine  for- 
mula is  less  liberal  in  recognizing  the 
torsional  moment  than  is  that  of  Gras- 
hof, it  is  safe  to  say  that  when  using 
the  Rankine  formula,  ample  provision 
is  made  for  the  fact  that  the  bending 
stresses  are  reversible,  even  when  a  con- 
stant allowable  safe  stress  is  assumed. 
[MACHINERY,  July,  1908,  Maximum 
Stresses.] 

Diameters  of  Shafts  for  Combined  Tor- 
sional and  Bending-  Stresses 

On  pages  18  and  19  are  given  tables 
for  the  diameters  of  shafts  subjected  to 
combined  torsional  and  bending  stresses. 
The  tables  are  arranged  for  fiber 
stresses  of  7500,  10,000  and  12,500 
pound's  per  square  inch.  As  an  example, 
find  the  diameter  of  a  shaft  to  sustain 
a  bending  moment  of  80,000  inch-pounds 
and  a  torsional  moment  of  100,000  inch- 
pounds,  if  a  fiber  stress  of  10,000 
pounds  per  square  inch  is  allowed.  By 
referring  to  the  table  on  page  18,  and 
locating  the  torsional  moment  as  given 
in  thousands  of  inch-pounds  at  the  top, 
and  the  oending  moment  as  given  at  the 
left-hand  side,  in  the  line  and  column 
corresponding  to  a  fiber  stress  of  10,000 
pounds  per  square  inch,  and  then  locat- 
ing in  the  body  of  the  table  the  diameter 
of  the  shaft  corresponding  to  these  mo- 
ments, we  find  that  the  diameter  re- 
quired is  4%  inches. 

One  difficulty  with  tables  is  the  inter- 
polation for  immediate  values.  A  dia- 
gram or  chart  is  much  better  in  this 
respect,  and  if  drawn  to  a  convenient 
scale  is  often  preferable.  On  pages  20 
to  23,  inclusive,  are  given  diagrams  for 
finding  the  diameter  of  shaft  required 
for  combined  torsional  and  bending 
stresses.  The  use  of  these  diagrams  is 
very  simple.  The  bending  and  torsional 
moments  in  thousands,  ten-thousands, 
hundred-thousands,  and  millions  of 
(Contlnuod  on  page  26.) 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


25 


WEIGHTS  AND  AREAS  OF  COLD  ROLLED  STEEL  SHAFTING. 

Diameter, 
Inches. 

Area,  . 
Square 
Inches. 

Circumference 
Inches. 

Weight  per 
Foot, 
Pounds. 

Diameter, 
Inches. 

Area, 
Square 
Inches. 

Circumference, 
Inches. 

Weight  per 
Foot, 
Pounds. 

A 

,0276 

,5890 

,095 

2A 

3.7583 

6,8722 

12,80 

i 

,0491 

,7854 

,167 

n 

3,9761 

7,0686 

13,52 

A 

,0767 

,9817 

,260 

2A 

4,2000 

7,2649 

14,35 

I 

,1104 

1,1781 

,375 

n 

4,4301 

7,4613 

15,07 

A 

,1503 

1,3744 

,511 

2A 

4,6664 

7,6576 

15,89 

} 

,1963 

1,5708 

,667 

2^ 

4,9087 

7,8540 

16,70 

T9* 

,2485 

1,7671 

,845 

lA 

5,1572 

8,0503 

17,55 

6 

¥ 

,3068 

1,9635 

1,05 

21 

5,4119 

8,2467 

18,41 

u 

,3712 

2,1598 

1,26 

2tt 

5,6727 

8,4430 

19,31 

! 

,4418 

2,3562 

1,50 

21 

5,9396 

8,6394 

20,21 

.it 

,5185 

2,5525 

1,77 

21! 

6,2126 

8,8357 

21,15 

?• 

,6013 

2,7489 

2,05 

21 

6,4918 

9,0321 

22,09 

« 

,6903 

2,9452 

2,35 

211 

6,7771 

9,2284 

23,06 

1 

,7854 

3,1416 

2,68 

3 

7,0686 

9,4248 

24,05 

1A 

,8866 

3,3379 

3,02 

3£ 

7,6699 

9,8175 

26,09 

n 

,9940 

3,5343 

3,38 

Si"* 

7,9798 

10,014 

27,16 

1A 

,1075 

3,7306 

3,77 

31 

8,2958 

10,210 

28,22 

H 

,2272 

3,9270 

4,17 

31 

8,9462 

10,603 

30,43 

1A 

,3530 

4,1233 

4,61 

SA 

9,2806 

10,799 

31,58 

11 

,4849 

4,3197 

5,05 

31 

9,6211 

10,996 

32,73 

1iV 

,6230 

4,5160 

5,52 

31 

10,321 

11,388 

35,20 

H 

,7671 

4,7124 

6,01 

3H 

10,680 

11,585 

36,40 

1l9TT 

,9175 

4,9087 

6,52 

31 

11,045 

11,781 

37,57 

1    1 

2,0739 

5,1051 

7,06 

11 

11,793 

12,174 

39,40 

Itt 

2,2365 

5,3014 

7,61 

311 

12,177 

12,370 

41,04 

11 

2,4053 

5,4978 

8,18 

4 

12,566 

12,566 

42,75 

1« 

2,5802 

5,6941 

8,78 

4i 

14,186 

13,352 

48,26 

11 

2,7612 

5,8905 

9,39 

4T7* 

15,466 

13,941 

52,62 

HI 

2,9483 

6,0868 

10,03 

41 

15,904 

14,137 

54,11 

2 

3,1416 

6,2832 

10,69 

4! 

17,728 

14,923 

60,88 

2iV 

3,3410 

6,4795 

11,35 

411 

19,147 

15,512 

65,50 

2* 

3,5466 

6,6759 

12,07 

5 

19,635 

15,708 

67,45 

MACHINFRY'S  Data  Sheet  No.  29.     Explanatory  note  :     Page  26. 


26 


MACHINERY'S  DATA  SHEETS 


No.  7 


inch-pounds,  as  the  case  may  be,  are  lo- 
cated at  the  left-hand  side  and  at  the 
bottom  of  the  diagram  respectively;  the 
horizontal  line  from  the  bending  mo- 
ment and'  the  vertical  line  from  the 
torsional  moment  are  followed  until 
they  intersect  as  shown  by  the  dotted 
lines  on  page  20.  The  curve  passing 
exactly  or  approximately  through  the 
point  of  intersection  then  indicates  the 
diameter  of  shaft  required.  In  the  ex- 
ample shown  on  page  20  it  will  be  seen 
that  the  lines  intersect  between  the 
111/16-  and  13/4-inch  curves.  It  is 
always  better  to  make  the  shaft  a  trifle 
stronger  than  necessary;  in  this  case, 
then,  one  of  1%-inch  diameter  would  be 
used.  This  shaft  would  be  of  the  re- 
quired size  to  transmit  a  torsional  mo- 
ment of  4000  inch-pounds,  and  could  in 
addition  sustain  a  bending  moment  of 
4000  inch-pounds,  at  a  fiber  stress  of 
10,000  pounds  per  square  inch,  these  be- 
ing the  known  requirements  from  which 
the  dotted  lines  in  the  diagram  were 
traced.  [MACHINERY,  July,  1908,  Maxi- 
mum Stresses.] 

Weights  and  Areas  of  Cold-rolled 
Steel  Shafting 

When  calculating  the  stresses  in  shaft- 
ing, the  weight  of  the  shafting  itself 
must  be  considered  whenever  the  dis- 
tance between  the  bearings  is  consider- 
able. The  table  on  page  25  will  be 
found  convenient  in  such  instances,  as 
it  gives  the  weight  per  foot  in  pounds 
of  cold  rolled  steel  shafting  from  3/16 
to  5  inches  diameter;  besides,  the  area 
in  square  inches  and  the  circumference 
in  inches  are  given.  In  calculating  the 
stresses  caused  by  the  weight  of  the 
shaft  itself,  the  total  weight  between  the 
bearings  is,  of  course,  considered  as 
uniformly  distributed  along  the  whole 
shaft,  the  shaft  being  assumed  to  be  sup- 
ported freely  at  the  bearings.  The  bend- 
ing moments  caused  by  pulleys,  belting, 
gears,  etc.,  are  then  determined  and 
these  are  added  to  find  the  total  bend- 
ing moment. 


Allowances  and  Tolerances  for 
Various  Kinds  of  Fits 

Running  fits,  as  implied  by  the  name, 
are  characterized  by  the  condition  that 
of  two  machine  members  fitted  together, 
cne  is  free  to  revolve  inside  or  about 
the  other,  the  fit,  however,  being  other- 
wise as  close  as  possible.  It  is  evident 
that  the  member  that  fits  inside  of  the 
other  must  be  a  very  small  amount  less 
in  diameter  than  the  hole  into  which 
it  fits. 

The  term  "forcing  fit"  is  used  when  a 
pin,  axle,  or  other  part,  which  is  some- 
what larger  than  the  hole  into  which 
it  is  inserted,  is  pressed  into  place  by  a 
hydraulic  press  or  by  other  means.  The 
crank-pins  and  axles  for  locoonotive  driv- 
ing wheels  are  usually  inserted  in  this 
way. 

The  term  "shrinking  fit"  is  applied 
when  a  part  which  is  to  be  held  in  po- 
sition by  being  tightly  fitted  into  a  hole 
is  first  turned  a  few  thousandths  of  an 
inch  larger  than  the  hole,  and  then  the 
diameter  of  the  hole  increased  by  heat- 
ing it,  after  which  the  pin  is  inserted 
in  the  heated  part.  When  this  part 
cools  down,  the  consequent  contraction 
of  the  metal  causes  it  to  grip  the  pin 
with  tremendous  pressure.  Locomotive 
tires,  for  example,  are  attached  to  their 
wheel  centers  by  means  of  a  shrinking 
fit. 

Allowances  and  tolerances  for  run- 
ning fits  recommended  by  the  Engineer- 
ing Standards  Committee  of  Great  Bri- 
tain are  given  on  page  27.  The  note 
at  the  bottom  of  the  page  should  be  care- 
fully read  before  using  the  table,  in 
order  to  avoid  misunderstandings. 

On  page  28  a  diagram  is  given  of  al- 
lowances for  forcing,  driving  and  run- 
ning fits  as  adopted  by  the  Builders' 
Iron  Foundry,  Providence,  R.  I.  In  the 
diagram  two  heavy  lines  are  drawn  for 
each  kind  of  fit,  the  upper  line  indicat- 
ing the  maximum  and  the  lower  line 
the  minimum  allowance  for  the  respec- 
tive diameter.  For  example,  assume 
(Continued  on  page  34.) 


No.  7  SHAFTING,  KEYS  AND  KEYWAYS 

ALLOWANCES  AND  TOLERANCES   FOR   RUNNING    FITS 


27 


Nominal 
D/crmefer 

<Shcrff 

/41/owance 
(Minimum 
Difference 
between  Shaft 
and  Ho  /e) 

Ho/e- 

Minimum 
Diameter 

Tolerance 
CDifference) 

Mcrximum 
Diameter 

Mr/imum 
Diameter 

To/erance 
(Difference) 

Maximum 
D/'amefer 

/nches 

Inches 

Inches 

Inches 

Inches 

Inches 

Inches 

/nches 

4 

O.2495 

o.ooos 

0.2S 

O.OOOS 

O.2SOS 

O.  OO03 

O.2S08 

i 

O.4993 

0.0007 

O.SO 

O.0007 

O.SO  07 

O.OOO7 

O.SO/4- 

f 

0.  7491 

0.0009 

0.7S 

O.OOO8 

0.7S08 

O.OOO9 

0.  7S/7 

1 

0.9990 

Q.OO/0 

I.OO 

o.oo/o 

I.OO/O 

O.OO/O  - 

/.OO2O 

4 

1.4988 

0.00/2 

/.SO 

O.OO/2 

/.SO/  2 

O.OO/3 

/.S02S 

2* 

/.993S 

0.00/S 

2.OO 

o.oo/s 

2.00/S 

O.OO/S 

2.003O 

3 

2.998Z 

0.00  IB 

3.OO 

O.OO/8 

3.OO/8 

•0.  00/7 

3.003S 

4- 

3.9930 

0.002O 

4.0O 

0.  0020 

4-.  O02O 

O.O020 

4.  OO4O 

S 

4.9980 

0.0020 

S.OO 

0.0020 

S.  0020 

0.0020 

S.0040 

0 

S.997S 

O.OO2S 

6.0O 

0.0  OSS 

6.  002S 

0.002S 

6.00SO 

7 

9.9975 

O.OO2S 

7.00 

O.OO2S 

7.O02S 

O.002S 

7.0OSO 

8 

7.997S 

O.002S 

8.0O 

o.oozs 

8JO2S 

O.002S 

8.00SO 

9 

8.9970 

O.OO3O 

9.OO 

0.0030 

9.OOJO 

0.0030 

9.00&O 

10 

9.997O 

0.0030 

10.00 

0.003O 

/O.OO3O 

O.OO30 

/O.OO&O 

II 

10.9970 

O.003O 

II.OO 

O.O03O 

//.OO30 

O.O030 

//.OO&O 

12 

//.997V 

0.  003O 

/2.00 

0.0030 

/2.O030 

O.0030 

/2.O060 

Note-.-   The  crbore  a/fowances  and  tolerances  for  running  fits  are 
recommended  by  the  Engineering  Standards  Committee  of  Great 
Britain  ',  for  first-  class  work.    For  second-  and  fhircf-c/ass  work, 
mu/fip/e/  the  fo/erances  by  2  and  3,  respecf/'re/t/.    /^orexfrcrf/he 
aua//'ty  of  work,  about  2/s  Me  abore  af/otrances  for  f/'rsf-c/ass  work 
are  recommended.    The  maximum  cf/'amefer-  of  the  snaff  is  f/?e 
nominal  diameter  in  a//  grades  of  /rortf. 

MACHINERY'S  Data  Sheet  No.  78.     Explanatory  note:     Page  26. 


28 


MACHINERY'S  DATA  SHEETS 


No.  7 


8888 

h* 

il'IS 

Diameters. 

LIMITS  FOB  STANDABD  HOLES. 

TH 

z 
z 

z 

0 
-n 

H 
0) 

ousXn 

UNbE 

NOHM/ 

D    H8 
R 

II 

TON 

ou 

/ER 

5AN 
N 

DT 
)M 

^S 
NA 

OF 
.   D 

AN 
AM 

IN 

ETE 

|S  Si  MAXIMUM 

a    | 

•J 

r 

L 

E 

c» 

^ 

S 

I 

Diameter  -  .00025 
Diameter  -  .00025 
Diameter  —  .0005 
Diameter  —  .001 

Minimum. 

0 

2 

m 
3] 

Z 

c 

x 

C 

CO 

& 

-  2 

z 
0 

z 

2 

C 

Diameter  +  .00025 
Diameter  +  .00075 
Diameter  +  .001 
Diameter  -t-  .001 

Maximum. 

r 

n 

M 

1AMET 

e> 

m 

XI 

z 

z 
o 
I 
m 

S 

^5 

:j- 

0 

m 
-n 

E 

H 

0) 

»i 

<i 

<i 

B 
*- 

No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 


29 


PRESSURE    FACTORS 


30 


MACHINERY'S  DATA  SHEETS 
DIAGRAM    FOR   RUNNING   FITS  AND  LIMIT  GAGES 


No.  7 


ALLOWANCES  FOR  RUNNING  FITS. 


.03T. 


.005 


.004 


.003 


.002' 


,001 


0"       1"        2"       3"       4'        5"       6"        1"       8"       9"       10"      11"      12"      13"      14"      15"     lliDia. 

A  =  allowance  in  inches.     D  =  nominal  diameter  of  fit  in  inches. 

0.31Z)  +  0.5 

For  running  fits,  A  = 

1000 


TABLE  OF  LIMITS  FOR  LIMIT  GAGES. 


.002 
.0015 

II 

.001 
.0005 


0 

.COOS' 
.001 


.002 


2"  3'  4"  5"  6"  7" 

total  limit  in  inches.     D  =  nominal  diameter  of  fit  in  inches. 
0.375  D  +  0.6 

1000 


8"Dia. 


ALLOWANCES  FOB  SHRINKING  FITS  ADOPTED  BY  THE  AMERICAN  MASTER 

MECHANICS'  ASSOCIATION. 


Diameter  of  tire,  in  inches 38  44  50  56  62 

Shrinkage  allowance,  in  inches 040         .047         .053         .060        .066 


.070 


From   a   paper   by    Stanley    H.   Moore   read    before   the   American    Society   of   Mechanical   Engineers. 
MACHINERY  s  Data  Sheet  No.  23.     Explanatory  notes:     Pages  26  and  39. 


No.  7 


SHAFTING,  KEYS  AND  KEY  WAYS 
FORCING,  SHRINKING  AND  DRIVING  FITS 


31 


4)16 


ui  .010 
o 


<.008 
.007 
.006 
.005 
.004 
.003 
.002 
.001 


E± 


18' 


13"      14'      15"     l6Dia 


A  =  allowance  in  inches. 


=  nominal  diameter  of  fit  in  inches. 

2  D  +  0.5 
For  forcing  fits,  A  = 


For  shrinking  fits,  A  = 


1000 

1.06  D  +  0.5 

1000 


For  driving  fits,  A  = 


0.5  D  +  0.5 
1000 


NOTE. — While  the  data  given  in  the  above  table  is  the  result  of  an  investigation  of  the  prac- 
tice of  a  large  number  of  shops,  the  allowances  for  the  large  diameters  is  considered  excessive,  as 
they  give  results  which  require  presses  of  more  than  ordinary  power  to  make  the  fits.  It  is  the 
practice  in  a  large  number  of  shops  to  decrease  the  allowance  per  inch  as  the  diameter  increases. 
The  general  rule  of  .001  inch  per  inch  of  diameter  has  been  found  very  satisfactory  for  sizes 
above  6  inches,  while  the  allowances  for  the  smaller  sizes  correspond  more  nearly  to  those  given 
above. 


From   a  paper  by   Stanley   H.  Moore   read   before   the  American    Society   of   Mechanical  Engineers. 
MACHINEUY'S   Data   Sheet   No.   23.     Explanatory   note :     Page   26. 


32 


MACHINERY'S  DATA  SHEETS 
WOODRUFF    KEYS— I 


No.  7 


i 

Woodruff  Jfcrncfcrrcf  ffet/s 
K  <*  -«| 

Tlr  .i          x-  —  x. 

/T 

n       c 

<-" 

'_  4_ 

'•f 

X---/    1 

V 

vly 

NO.  Of 

Key 

Diam.  of 
Key 

Thickness 
of  Key 

£ty»/A  «^ 
ffeytvay 

Center  of 
stocK.frvm 
which  Hey 
ismade.fo 
fop  of  Key 

NO  Of 

Key 

Diam.  of 
Key 

Thickness 
of  Key 

Depth  of 
Heytray 

Center  of 
stock,  from 
which  key 
is  made,  fo 
top  of  key 

ct 

b 

C 

a 

a 

b 

C 

ct 

1 

t 

l 

.& 

* 

B 

i 

1 

J 

k 

2 

i 

h 

A 

A 

,* 

4 

4 

32 

£ 

3 

i 

* 

^ 

b 

f7 

>i 

£ 

* 

£ 

4 

s 

A 

& 

& 

» 

& 

k 

1 

4 

* 

* 

i 

1 

k 

C 

''t 

I 

£ 
52 

A 

0 

* 

.3? 

£ 

k 

/9 

'k 

3 

h 

i 

7 

1 

i 

/i 

T* 

20 

'k 

£ 

k 

4 

8 

* 

>S 

£ 

76 

21 

'k 

k 

i 

A 

9 

f 

4 

A 

k 

0 

4 

1 

& 

£ 

10 

& 

j£ 

4 

k 

£ 

'k 

I 

1 

£ 

II 

Ir 

i 

32 

re 

22 

'J 

i 

i 

3 
32 

/£ 

1 

/2 

I 

Te 

23 

/I 

1 

k 

k 

A 

i 

4 

''e 

k 

'_ 

/I 

1 

4 

J2 

13 

/ 

1 

& 

it 

24 

'.? 

k 

'-s 

£ 

14 

/ 

b 

64 

76 

25 

4 

£ 

fz 

£ 

,5 

/ 

6 

b 

76 

G 

^ 

1 

4 

i 

MACHINBKT'S    Data    Sheet    No.    81.     Explanatory    note :     Page    39. 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 
WOODRUFF   KEYS— II 


33 


yyooc/ruff  Spec/af  Xet/s 

.  A 

KCf                                        >J 

)/ 

Ct 

\     i                             ! 

(                                                J 

a 

c 

i          X^—  "X/     1   / 

\    t 

1                       J   V 

~* 

\    e                                 L 
\~T                           / 

No.  of 
Key 

Dictm.  of 
Hey 

Thickness 
of  Hey 

Deptnof 
Keyway 

Centerof 
stock,  from 
which  key 
is  made,  fo 
top  of  key 

W/dfn  of 
F/at 

No.  of 
Hey 

Diam.  of 
Hey 

Thickness 
of  Key 

Depfnof 
Heyway 

Centerof 
sfockjrom 
which  key 
ismacfejo 
top  of  key 

Mcff/t  of 

a 

b 

c 

ct 

e 

a 

b 

C 

c( 

e 

2<5 

4 

% 

32. 

/7 
32 

32 

3f 

f 

T<5 

h 

f 

}* 

27 

4 

k 

''8 

& 

k 

32 

4 

i 

k 

f 

T0 

28 

4 

s 
Te 

32 

'J 

k 

33 

4 

S 

3Z 

f 

% 

29 

4 

I 

I 

& 

32 

34 

* 

* 

S 

10 

12 

9 

fe 

30 

4 

* 

T& 

f 

3 
I 

Standard  Keys  fo  use  w/ffy  rar/ous  cf/'amefer  ^hcrfte 

Diameter  of 
Shaft 

Number  of 
Keys 

D/amerer  of 
Sftcrff 

Number  of 

D/amefer  of 
Sfiaff 

Number  of 
Key* 

•£  —  2 

1 

7        US 

'8  ~  T0 

6,  8,  10 

'I  -'I 

14,  17,  2O 

7           1 

16       2 

2,4 

1 

9,  //,  /3 

4-4 

J£,  /e,  2/,  24 

J0  ~  8 

3,5 

4  -  4 

4.4  «* 

<%->$ 

J8,  2/f  24 

-  -\ 

s,*,r 

//! 

//^   /J,  /^ 

#-2 

21,2* 

(3 

0,8 

4-4 

/£",  A?f  /7,  20 

4-^ 

2S 

MACHINEUY'S    Data    Sheet    No.    81.     Explanatory    note :     Page    39. 


MACHINERY'S  DATA  SHEETS 


No.  7 


that  it  is  required  to  find  the  diameter 
to  which  to  turn  a  pin  to  be  fitted  by  a 
forcing  fit  into  a  standard  7-inch  hole. 
By  locating  7  on  the  line  marked 
"Nominal  diameter  in  inches,"  and  fol- 
lowing the  vertical  line  from  7  until  it 
intersects  the  heavy  lines  for  forcing 
fits,  it  will  be  seen  that  the  pin  should 
be  from  0.009  to  0.010  inch  above  the 
nominal  diameter.  If  a  running  fit  had 
been  required  instead  of  a  forcing  fit,  we 
would  have  followed  the  line  downward 
from  7  until  intersecting  the  heavy  lines 
representing  the  limits  for  running  fits. 
Assuming  the  hole  to  be  standard  size 
as  mentioned,  the  pin  should  thus  have 
been  turned  from  0.0025  to  0.004  inch 
below  the  size  of  the  hole.  In  the  case 
of  running  fits,  however,  it  is  almost 
always  the  practice  to  make  the  diam- 
eter of  the  shaft  the  standard  or  nomi- 
nal size,  and  to  provide  for  the  allow- 
ance in  the  hole.  In  such  a  case  the 
shaft  would  have  been  made  7  inches  in 
diameter  while  the  hole  would  have 
been  made  from  7.0025  to  7.004  inches 
in  diameter. 

Whether  parts  should  be  assembled  by 
pressing  them  into  place  or  by  the 
shrinking  method  depends  somewhat 
upon  circumstances.  To  press  a  tire, 
for  example,  over  a  wheel  center,  would 
be  a  rather  difficult  job,  owing  to  the 
size  and  shape  of  the  work.  On  the 
other  hand,  a  pin  is  easily  forced  into 
place  with  a  hydraulic  press  if  such  a 
tool  is  available;  otherwise  the  hole  can 
be  heated  and  expanded  sufficiently  to 
permit  the  insertion  of  the  pin  by  sledg- 
ing or  even  by  hand.  The  hydraulic 
press  is  more  economical  for  most  work, 
and  in  addition  there  is  an  advantage 
in  its  use  in  that  the  exact  pressure  or 
tonnage  required  to  force  the  part  into 
place  is  indicated  by  a  gage,  while  there 
is  more  or  less  uncertainty  connected 
with  a  shrinking  fit.  If  the  allowance 
when  turning  a  pin  for  a  shrinking  fit 
were  too  great,  the  part  into  which  the 
pin  is  fitted  might  be  broken  when 
cooled  down,  owing  to  the  excessive 


stresses  produced.  When  using  a  press 
this  danger  is  largely  eliminated,  as  the 
approximate  pressure  required  can  be 
calculated,  and  the  pressure  gage  indi- 
cates at  every  moment  what  the  actual 
pressure  is.  Tests  have  demonstrated, 
however,  that  a  shrinking  fit  is  superior 
to  a  forcing  or  press  fit,  as  the  assem- 
bled parts  are  held  more  securely  to- 
gether. 

The  ultimate  pressure  finally  required 
to  force  the  pin  or  other  part  into 
place  depends  not  only  upon  the  allow- 
ance for  the  fit,  but  also  upon  the  length 
of  the  bore  or  the  area  of  the  surface 
of  the  fit.  The  pressure  required  for 
forcing  a  pin  with  a  given  allowance 
into  a  hole  may  be  determined  by  the 
formula  given  with  the  diagram  on  page 
29,  where  the  pressure  factor  PF  is  de- 
termined from  the  diagram.  This  pres- 
sure factor  varies  with  the  diameter  of 
the  pin.  For  example,  if  the  pin  is  6 
inches  in  diameter,  then  we  find  from 
the  diagram  that  the  pressure  factor  is 
75.  To  find  this,  we  locate  6  on  the 
scale  at  the  bottom  of  the  diagram,  and 
follow  the  vertical  line  from  the  point 
so  located  until  it  intersects  the  curve 
drawn  on  the  diagram;  from  the  point 
of  intersection,  we  follow  the  horizontal 
line  to  the  scale  at  the  left  where  the 
pressure  factor  75  is  read  off.  The  ex- 
ample given  in  connection  with  the  dia- 
gram and  formula  indicates  clearly  their 
use  for  practical  calculations. 

The  diagrams  for  running,  forcing, 
shrinking  and  driving  fits  given  on 
pages  30  and  31  are  compiled  from  a 
paper  read  by  Stanley  H.  Moore  before 
the  American  Society  of  Mechanical  En- 
gineers, and  are  the  results  of  an  inves- 
tigation of  the  practice  in  a  large  num- 
ber of  shops.  Before  using  these  dia- 
grams, however,  the  note  at  the  bottom 
of  page  31  should  be  read  and  compari- 
son made  with  the  diagram  on  page  28. 
The  use  of  the  diagrams  on  pages  30 
and  31  is  very  simple.  On  the  scale  at 
the  bottom  of  the  diagrams  are  given 
(Continued  on  page  39.) 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 
DIMENSIONS  OF  KEYS— I 


35 


PROPORTIONS  OF  KEYS. 

(United  States  Navy  Standard.) 


D=0 


r  8*  9"  10 

InduatrinLPresa,.  K.  F. 


w 


W 


f" 
I" 
1" 
U" 
H" 
11" 
H" 
1!" 
2" 

21" 
2f" 
3' 

31  ' 
31" 


A" 

H" 
i" 


A" 


i" 

8 
6   " 

B 

-H" 


A" 
A" 


sa 

I" 

I" 
TV 


A" 

iV 

i" 


4" 

41" 
41" 
5" 

51" 
5£" 
6" 


61" 

7" 
7i" 

71" 
71" 


ir' 
i" 
1" 

1iV 
U" 

1A" 


1A" 

1A" 
1A" 


\" 

TV 

A" 

TV 
I" 


H" 


11" 


8" 
8i" 

81" 

9' 

9i" 

9!" 
10" 


If" 

11" 
11" 

H" 
11" 


2" 
2" 


i" 
«" 

ir 

ir 
1" 
1" 


MACHINERY'S  Data  Sheet  No.  33.     Explanatory  note  :     Page  39. 


36 


MACHINERY'S  DATA  SHEETS 
DIMENSIONS  OF  KEYS—  II 


No.  7 


TABLE    OF    GIB    KEYS.      Computed  by  F.  D.  Buffum,  Akron,  O 


Indu»trial  frest,  N^K. 


Keys  of  proportions  given  below  are  weakest  in  shear. 

The  safe  twisting  moment  per  inch  of  length  of  keys  =  R  B  S 

R  =  Radius  of  shaft. 

B  =  Breadth  of  key. 

S  =  Safe  shearing  strength  of  material  in  key. 

B  =  ^  bore  up  to  6  inches.    Then  B  =  .211  bore.    Taken  to  eighths. 

G  =  B  approximately. 

H  =  £  bore  up  to  6  inches.    Then  H  =  £  bore. 

h  =  Radius  =  £  bore  taken  to  eighths.    But  minimum  value  =  -ft  inch. 

L  =  Length  of  hub  +  |  inch. 
Taper  -J-  inch  per  foot. 


Bore  and  Shaft 
Diameter. 


If  to 
1Ato 
1ft  to 
IHto 

m  to 

2ft  to 
2ft  to 
244  to 
2Hto 
3ft  to 
3ft  to 
3i4to 
3H  to  .  o 
4ft  to*  4! 
4ft  to  4! 
51 
to 

-xo  to 
6ft  to 


14 
II 
It 
11 
2i 
21 
21 
21 

3! 
31 
31 

4* 


5! 
61 
61 
71 
71 
81 

8[lto    9* 

Sit  to  10  f 

10if  to  111 

IHtto  121 


7ft  to 


Width 
of  Key 


1 
I 
I 

I 

* 
T 

2 

21 
24 
24 


Height 

of  Key 

n. 


ft 

4 

1 
A 

I 


I 

U 
U 
I 

7 


Depth 


i 
i 

A 

ft 


1 
1 

A 
A 

ft 
44 
44 

t 
ft 
ft 


4 
ft 


h  and 
Bad. 


A 
A 

i 
1 
I 

I 


I 
f 
f 
t 
t 
I 
4 
1 
1 

14 
11 
11 
11 


Safe  Twisting  Moment  on  Key  per  inch 
of  Length  for  S  = 


5000 


1 
1 
1 

1 

H 

H 

H 

H 

11 

It 

2 

2 

2 

2 

2 


630 

1170 

1410 

2190 

2500 

3520 

3910 

5160 

5620 

7110 

7660 

9380 

10000 

11950 

12660 

15620 

18910 

22500 

24380 

26250 

30470 

36090 

46250 

57660 

70310 

76560 


7500 


10000 


940 

1760 

2110 

3280 

3750 

5270 

5860 

7730 

8420 

10660 

11480 

14060 

15000 

17930 

18980 

23440 

28360 

33750 

36560 

39380 

45700 

54140 

69380 

86480 

105470 

114840 


1250 

2340 

2810 

4380 

5000 

7030 

7810 

10313 

11250 

14220 

15310 

18750 

20000 

23910 

25310 

31250 

37810 

450GO 

48750 

52500 

60940 

72190 

92500 

115320 

140630 

153130 


MACHINERY'S  Data  Sheet  Is7o.   14.     Explanatory  note:     Page  3!». 


No.  7 


SHAFTING,  KEYS  AND  KEYWAYS 
TABLE  FOR  USE  WHEN   MILLING  KEYWAYS 


37 


K~£-->j           ,-A 

O~~~x<\]^        T^SN""^                 ^*  va/ue$  in  the  body  of  the  fab/e  give  the 
"^'7^^^^^^^^^^^^\                dimension  A,  which  shoufcf  be  added  fo  fhe 
/"^oooooooJoo^oSoo^ov             deplh  C  of  the  key  way  in  order  to  f/'ncf  the 
/^^^V^^^S^A             fofaldepfh  from  fhe  oufs/de  of  'the  shaff 
^^^^^^^^^^^^            to  fhe  boffom  of  fhe  key  way.  When  mi  //ing 
^^^^^^^^^^^^|           key  ways,  fhe  cuffer  can  fnen  be  fed  down 
V^\X^\\\\\\\xv\xx\xy            this  fofaf  depfhf  and  no  further  measc/i  —  ; 
\$oooo^ooo^$ooSo/              ing  is  necessary. 

Stze 

of 
Shaft 

Width  of  Key  way  B 

Size 
of 
Shaft 

Wictfh  of  Key  way  B 

l/4 

f* 

% 

7 
/£ 

j_ 

i 

% 

% 

re 

Lz 

i 

0.0325 

— 







2% 

0.0  OG8 

0.0104 

o.otss 

O.0209 

O.0274 

% 

0.0289 

— 

— 



— 

*4 

0.0066 

0.0102 

O.OIS2 

O.OZ02 

O.O267 

% 

0.0254 

O.O4I3 

— 



— 

*fc 

0.0064 

O.OIOO 

O.OI  49 

O.OI  98 

O.O26O 

% 

0.02  3  e 

0.0379 

— 



— 

z'-2 

0.0063 

O.0038 

O.O/46 

O.OI  94 

0.02S3 

% 

0,0220 

O.0346 

O.OSII 



— 

z*',e 

O.OO6I 

O.OO94 

0.0142 

O.O/89 

O.O247 

\ 

0.0198 

0.0314 

O.046S 



-  — 

2* 

O.OO6O 

O.OO9O 

O.O/39 

0.0/8S 

0.0242 

1 

0.0/77 

0.0283 

O.042O 

O.OS83 

— 

z"K 

O.OOS9 

O.O089 

O.OI  36 

O.O/&O 

0.0236 

\ 

o.oie4 

0.0264 

0.0392 

O.OS44 

— 

,?$ 

O.OOS8 

O.OO8& 

O.OI33 

O.OI  76 

0.0230 

i 

0.0  1  S2 

O.0246 

O.036S 

O.OS06 

O.067O 

2% 

0.0051 

O.0086 

O.0129 

O.OI72 

O.O226 

ihe 

O.OI43 

0.0228 

0.0342 

0.0476 

0.062S 

Z7'8 

O.OOS6 

O.O084 

O.OI26 

O.OI  68 

0.0220 

?i 

O.OI36 

O.02IO 

0.03/9 

O.0446 

O.OS3I 

^ 

O.OOS4 

O.O083 

O.OI  22 

O.OI64 

0.02/6 

1% 

0.0131 

O.02O4 

0.0304 

0.042  / 

O.OSSI 

3 

O.OOS3 

O.008I 

O.OI  19 

0.0161 

0.0211 

/fe 

0.0/27 

O.OI  98 

O.O29O 

0.0397 

0.0  S2  2 

^ 

O.OOS2 

O.OOSO 

O.OI  16 

O.O/S8 

O.O2O7 

/5 

0.0/23 

O.OI9I 

O.O279 

O.O38O 

O.0499 

^ 

O.OOS/ 

0.0078 

O.OI  14 

O.OfSS 

0.0202 

/^ 

0.0120 

0.0  18S 

0.0  268 

O.0364 

O.O477 

3*,e 

o.ooso 

O.O076 

O.O//2 

O.OI  £7 

0.0198 

75 

0.0  1  14 

0.0174 

0.0  2  S4 

0.0346 

0.04S3 

3k 

O.OO49 

0.007S 

O.Ot  10 

O.O/49 

0.0/94 

75 

o.oi  to 

O.O/64 

O.OZ4O 

0.0328 

O.0429 

&* 

0.0048 

O.0074 

O.OI  08 

O.OI  46 

0.0/91 

75 

0.01  Of 

0.0  IS8 

0.0231 

O.O3O9 

O.04/2 

3% 

O.0047 

O.OO72 

o.o/oe 

O.O/43 

0.0/87 

5 

0.01  OS 

O.OI  S3 

O.OZ2I 

O.029I 

0.039S 

3\ 

O.OO46 

0.0071 

0.0104 

O.O/40 

0.0/84 

i"',e 

0.0102 

O.O/47 

O.OZ/4 

0.0282 

O.0383 

3''t 

0.0  04S 

O.007O 

O.OIO2 

0.0/36 

O.O18O 

1 

O.0099 

O.OI  42 

O.02O7 

O.0274 

0.0371 

3% 

0.0044 

O.O069 

O.O/O/ 

O.O/3S 

0.0/77 

a 

0.0  093 

0.0/30 

0.0198 

O.026S 

O.O3SS 

3% 

O.0043 

O.OO67 

O.OIOO 

O.O/33 

O.OI  74 

/% 

0.  0093 

O.O13O 

O.OI9O 

O.O257 

O.O339 

3% 

O.O042 

O.O066 

O.OO99 

0.0131 

O.O/7f 

^ 

O.009O 

0.0  /  27 

0.0184 

O.O2SO 

0.0328 

3\ 

O.0042 

O.006S 

O.O098 

O.OI  28 

0.0/68 

2 

O.OO88 

O.OIZ4 

0.0/79 

O.OZ43 

O.O3/7 

3''*/6 

O.004I 

O.O064 

0.0097 

O.OI26 

0.0166 

ii 

O.0083 

O.OI  17 

O.O/73 

O.0236 

O.O3O8 

3\ 

O.004I 

O.0063 

O.0096 

0.0124 

0.0163 

?5 

O.OO78 

O.OI  1  1 

O.OI  68 

O.OZZ9 

0.0299 

3$* 

O.004I 

O.OO62 

O.OO9S 

O.O/23 

OjO/6/ 

Z*,6 

O.0073 

O.OI  O9 

O.OI63 

0.0222 

O.O29I 

4 

O.OO4O 

o.ooet 

O.OO94 

0.0/2  / 

O.OI6O 

2k 

O.OO7O 

O.O/O7 

O.OIS9 

O.OZI6 

0.0282 

Contributed  by  James  J.  Loftus.     Explanatory  note:     Page  39. 


MACHINERY'S  DATA  SHEETS 
DUPLEX    KEYS 


No.  7 


A 


B 


Bore  of 
Hollow 
Shaft 

D 


21 


22 


*% 


23 


24 


2S 


>*& 


1 


26 


(f 

m 


27 


28 


30 


'*$ 


31 


I  0 


32 


/o 


1  1 


3% 


33 


II 


12 


13 


14 


4*4 


34 


35 


36 


9% 


n?6 


ff, 


/z 


No.  7 


SHAFTING,  KEYS  AND 


39 


the  diameters  in  inches,  and  on  the 
scale  at  the  left-hand  side  the  allow- 
ances. Assume,  for  example,  that  we 
want  to  find  the  allowance  for  a  shrink- 
ing fit  for  a  4-inch  diameter  pin.  Re- 
ferring to  page  31,  we  find  by  following 
the  vertical  line  from  4  inches  until  it 
intersects  the  diagonal  line  for  shrink- 
ing fits,  and  from  the  point  of  intersec- 
tion following  the  horizontal  line  to  the 
left-hand  scale,  that  an  allowance  of 
nearly  0.005  inch  is  required. 

Allowances  for  shrinking  fits  adopted 
by  the  American  Master  Mechanics  As- 
sociation are  given  at  the  bottom  of 
page  30.  These  allowances  refer  direct- 
ly to  tires  to  be  shrunk  onto  their 
wheel  centers.  [MACHINERY,  July,  1909, 
Machine  Shop  Practice — Shrinking  and 
Forcing  Pits.] 

Diagram  of  Limits  for  Limit  Gages 

On  page  30  a  diagram  is  given  show- 
ing suitable  maximum  and  minimum 
limits  for  limit  gages  for  ordinary  work. 
It  will  be  understood  that  the  upper 
and  lower  diagonal  lines  in  this  dia- 
gram indicate  the  maximum  and  mini- 
mum limits  corresponding  to  various 
diameters.  To  find  the  limits  for  any 
given  diameter,  say  6  inches,  this  di- 
mension is  first  located  on  the  bottom 
scale,  and  the  vertical  line  from  6  inches 
is  followed  until  it  intersects  the  lower 
diagonal  line.  From  the  point  of  inter- 
section the  horizontal  line  is  followed 
to  the  left,  and  the  minimum  limit  read 
off.  This  diagram  is  made  up  on  the 
principle  that  the  maximum  limit  is  as 
much  above  standard  size  as  the  mini- 
mum limit  is  below  standard  size,  so  that 
when  the  minimum  limit  has  been  found 
there  is  no  need  of  locating  the  maximum 
limit.  For  a  4-inch  diameter  shaft,  for 
example,  the  allowable  limits  would  be 
very  slightly  more  than  0.001  inch  above 
or  below  the  standard  size. 

Keys 

On  pages  32  and  33  are  given  tables 
of  Woodruff  standard  and  special  keys. 


In  the  lower  part  of  page  33  a  table  is 
also  given  of  Woodruff  standard  keys 
to  be  used  with  various  shaft  diameters. 
It  will  be  seen  that  the  designer's  judg- 
ment must  be  relied  upon  to  a  certain 
extent,  as  a  number  of  different  sizes  of 
keys  may  be  used  for  the  same  diam- 
eters. For  ordinary  practice,  when  no 
special  considerations  have  to  be  taken 
into  account  and  where  more  than  two 
keys  are  given  for  the  same  diameters, 
the  medium  size  key  is  the  most  suit- 
able. 

On  page  35  is  given  a  diagram  and 
table  of  the  United  States  Navy  stand- 
ard proportions  of  keys.  The  diagram 
is  shown  only  to  indicate  how  the  sizes 
were  determined  by  plotting  the  dimen- 
sions from  a  curve  supposed  to  give  the 
best  theoretical  dimensions.  When  us- 
ing the  information  given  on  page  35, 
no  attention  need  be  paid  to  the  dia- 
gram, but  the  table  should  be  used  di- 
rectly, as  all  the  required  information  is 
contained  therein. 

On  page  36  is  given  a  table  of  gib 
keys.  In  addition  to  the  dimensions,  it 
will  be  seen  that  the  safe  twisting  mo- 
ments which  the  key  will  sustain  for 
each  inch  of  length,  at  different  shear- 
ing stresses,  are  given.  This  informa- 
tion will  be  of  considerable  value  in 
quickly  calculating  the  strength  of  keys 
when  the  twisting  moment  is  known. 
[MACHINERY,  September,  1901,  Notes  on 
Keys  and  Key  ways;  March,  1907,  Keys 
and  Key  ways;  MACHINERY'S  Reference 
Series  No.  22,  Calculation  of  Elements 
of  Machine  Design,  Chapter  VI,  Keys 
and  Keyways.] 

Table  for  Use  when  Milling 
Keyways 

The  table  given  on  page  37  will  be 
found  very  useful  when  milling  keyways 
to  a  given  depth.  The  usual  way  of 
measuring  the  depth  of  a  keyway  is  to 
mill  off  the  top  of  the  shaft  until  the 
flat  on  the  top  is  of  the  same  width  as 
the  cutter.  Then  the  index  is  set  to 
zero  and  the  cutter  is  fed  down  the  re- 


40 


MACII/XERY'S  DATA  SHEETS 


No.  7 


quired  depth  C  (see  page  37).  When 
milling  off  the  top  of  the  shaft,  difficulty 
is  experienced  in  measuring  properly 
the  width  of  the  flat.  By  means  of  the 
table  a  more  accurate  measurement  can 
quickly  be  obtained.  Bring  the  cutter 
down  so  that  it  will  just  touch  the  work 
on  the  top,  and  set  the  index  to  zero. 
Then  add  the  figures  given  in  the  body 
of  the  table  for  the  given  size  of  shaft 
and  width  of  keyway,  to  the  depth  C 
of  the  keyway.  This  gives  the  total 
depth  from  the  outside  of  the  shaft  to 


the  bottom  of  the  keyway.  For  ex- 
ample: If  the  size  of  the  shaft  is  3 
inches  and  the  width  of  the  keyway  one- 
half  inch,  then,  from  the  table,  we  find 
that  0.0211  inch  should  be  added  to  the 
given  depth  C  of  the  keyway — usually 
made  half  the  width  B — in  order  to  find 
the  total  depth  from  the  top  of  the  shaft 
to  the  bottom  of  the  keyway.  In  this 
case,  then,  this  dimension  would  be 
0.250  +  0.0211  =  0.2711  inch.  [MA- 
CHINERY, December,  1908,  Keyway  Gag 
ing  in  Shafts  and  Hubs.] 


AN  INITIAL  FINE i  Ol ;  »  OM« 

W,LU  BE  *«•»•»   "^ES.    TOE   PENALTY 
THIS   BOOK  ON  T  t*D*'™°     ON  THE  FOURTH 

O.Y 


TU 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


No.  16.     Machine    Tool    Drives.— Sp 

and     Feeds    of    Machine    Too;  :    or 

Singh-  Pulley  Drives;  Drives  for  High 
Speed  Cutting  Tools. 

No.  17.     Strength      of      Cylinders  -For 

mulas,    Charts,    and    Diagrams. 

No.  18.     Shop    Arithmetic    for    the    Ma 
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Speeds:    Feeds;    Ind.  -ring  for  ' 

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No.  19.     Use  of  Formulas  in  Mechanics. 

—  With    numero!  lions. 

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No.   21.      Measuring  Tools. — History  and 
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and   Key  ways;    Toggle-joints. 

No.  23.     Theory   of   Crane    Design. — Jib 

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Bearings;  Force  Required  to  Move  Crane 
Trolleys;  Pillar  Cranes. 

No.  24.  Examples  of  Calculating*  De- 
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Riveter  Frames;  Shear  Frames;  Billet 
and  Bar  Passes 

No.  25.     Deep    Hole    Drilling.— Methods 

of  Drilling;   Construction  of  Drills. 

No.  26.     Modern    Punch    and    Die    Con- 
struction.—Construction   and    I'se   of   Sub- 
Modern     Blanking    Die     Con- 
struction;   Drawing  and   Forming    Dies. 

No.  27.     Locomotive    Design,    Part    I. — 

Boilers,    Cylinders,    Pipes   and   Pistons. 

No.  28.     Locomotive    Design,    Part   II. — 

Stephenson  Valve  Motion;  Theory.  Calcu- 
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Walschaerta  Valve  Motion. 

No.  29.     locomotive    Design,    Part    III. 
lokehox;       Fxhaust       Pipe;       Frames; 

Cross-heads:  Cuide  .Bars;  Connecting-rods; 
('"rank-pins;  Axles;  Driving-wheels. 

No.  30.  Locomotive  Design,  Part  IV. — 
Springs.  Trucks,  Cab  and  Tender. 

No.  31.     Screw  Thread  Tools  and  Gages. 

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Chan  Thread    Tc.«ds;    Kinks. 

No.  33.  Systems  and  Practice  of  the 
Drafting-Room. 

No.  34.  Care  and  Repair  of  Dynamos 
and  Motors. 

No.  35.  Tables  and  Formulas  for  Shop 
and  Drafting-Room. — The  I'se  of  Formu- 
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Materials;  clearing:  Screw  Threads;  Tap 
Drills;  Drill  Sixes;  Tapers;  Keys:  Jig 
Bushings, 

No.  36.  Iron  and  Steel. — Principles  of 
Manufacture  and  Treatment. 


Tooth    Outlines;    Strength    and    Dnrabi! 
I  >esign  ;    Methods   of   '  •  et  h. 

No.  38.     Grinding     and      Grinding     Ma 
chines. 

No.  39.     Fans,  Ventilation  and  Heating. 

ns;    Heaters;    Shop    Heating. 

No.  40.     Ply-Wheels. — T  h  e  i  r    Purp 

Calculation    and    Design. 

No.  41.      Jigs    and    Fixtures,    Part    I.— 

Principles  of  Jig  and  Fixture  Design; 
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Points;  Clamping  Devices. 

No.  42.      Jigs    and    Fixtures,    Part    II. — 

Open  and  Closed   Drill  Jigs. 

No.  43.     Jigs   and  Fixtures,   Part   III. — 

Boring  and   Milling   Fixtures. 

No.  44.  Machine  Blacksmi thing. — Sys- 
tems, Tools  and  Machines  used. 

No.  45.  Drop  Forging. —  Lay-out  of 
Plant;  Methods  of  Drop  Forging;  Dies. 

No.  46.  Hardening"  and  Tempering. — 
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Steel;  Hardening  Gages;  Hardening 
Kinks. 

No.  47.  Electric  Overhead  Cranes. — 
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No.  48.  Files  and  Filing.— Types  of 
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No.  49.  Girders  for  Electric  Overhead 
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No.  50.  Principles  and  Practice  of  As- 
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No.  51.  Principles  and  Practice  of  As- 
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No.  52.  Advanced  Shop  Arithmetic  for 
the  Machinist. 

No.  53.  Use  of  Logarithms  and  Logar- 
ithmic Tables. 

No.  54.     Solution    of   Triangles,    Part    I. 

— Methods,    Rules   and    Kxamples. 

No.  55.     Solution  of  Triangles,  Part   II. 

— Tables    of    Natural    Functions. 

No.  56.  Ball  Bearings.— Principles  of 
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No.  57.     Metal  Spinning.— M  a  c  h  i  n  e  s( 

Tools   and    Methods 

No.  58.     Helical  and  Elliptic  Springs.— 

Calculation   and  Design. 

No.  59.  Machines,  Tools  and  Methods 
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No.  60.  Construction  and  Manufacture 
of  Automobiles. 

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Hardening.  Tempering  and  Case-Harden- 
ing. 

No.  64.     Gage  Making  and  Lapping. 

No.  65.  Formulas  and  Constants  for 
Gas  Engine  Design. 


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