APPENDIX OF TABLES 371
To calculate the output of a machine:
Multiply the deckle width in inches by the speed in feet per minute; multiply
the result by the substance of the paper in double crown (20 x 30) 480'$. Divide
the result by 400. The resulting figure is the number of pounds per hour.
Example: Deckle=i30 inches. Speed=6oo feet per minute. Substance=
20 Ib. double crown 480 sheets.
130x600x20 tl -
---------------=3900 Ib. per hour.
400 r
Another method:
To calculate the output of a machine: Multiply weight per ream by speed
per hour in inches by width of web in inches, and divide the result by length
of sheet multiplied by breadth of sheet and by number of sheets per ream.
Weight per ream x speed per hour in inches x width of web
Length of sheet x breadth of sheet x sheets per ream
Example: Speed, 100 feet per minute. Deckle width, 68 inches. Sub-
stance, 16-^x21=21 Ib. 500 sheets.
2ix(iooxi2X6o)x68 R 11 i
-----^—------------------=593 £ Ib. per hour.
16^x21x500 r
To find equivalent weights of different sizes of sheets: Multiply known
ream weight by length and breadth of sheet, the weight of which is required,
and divide the result by length and breadth of sheet the weight of which is
known.
Ream weight x (length and breadth of sheet of unknown weight)
Length x breadth of sheet of known weight
Example: Sheet 20x25=25 Ib. per ream.
Find equivalent weight of sheet 20x30:
25X(20X30) =
20X25
To find the .weight of paper required for a web of a given length, breadth
and substance:
Multiply the ream weight by the length of web in inches and by the breadth
in inches; divide the result by the number of sheets per ream, multiplied by
the length and breadth of sheet.
Ream weight x length of web in inches x breadth of web in inches
Sheets per ream x length of sheet x breadth of sheet