USEFUL INFORMATION
CALCULATION OF DRUM CAPACITIES
CAPACITIES IN FEET OF ROPE (A + B) ACM
Example
How much 1/4″ diameter rope can be spooled on a drum having a 36″ diameter flange, 24″ diameter drum and 30″ width between flanges?
Using the above formula the number of feet equals (6 + 24) x 6 x 30 x .152 Answer — 821 feet. The value of “M” is taken from the previously calculated table of values shown below. For 1/4″ diameter this value “M” is .152
Values for M
| Size Rope Inches | M | Size Rope Inches | M | Size Rope Inches | M |
| 1/4 | 3.29 | 7/8 | .308 | 1 3/4 | .0770 |
| 3/8 | 1.58 | 1 | .239 | 1 7/8 | .0675 |
| 7/16 | 1.19 | 1 1/8 | .191 | 2 | .0597 |
| 1/2 | .925 | 1 1/4 | .152 | 2 1/8 | .0532 |
| 3/16 | .741 | 1 3/8 | .127 | 2 1/4 | .0476 |
| 5/8 | .607 | 1 1/2 | .107 | 2 3/8 | .0419 |
| 3/4 | .428 | 1 5/8 | .0886 | 2 1/2 | .0380 |
