Length of Cable for Winch Drum
Ok bear with me... :D If I type this is correctly this formula really should be in the tools link thingy...
So you first need to know a few things...
A: depth of line on drum to find, A= (H-D-2Y)/2
B: width of drum between flanges
D: Drum barrel diameter (the bit the cable wraps around)
H: Diameter of flanges
K: factor from table to follow
Y: Depth of drum not filled (you don't want a full drum unless you like picking cable out of bearings and stuff)
L: Length of cable.
K factors for dia of cable, followed by breaking strength of standard rope in tons
1/2=.925 9.35
9/16=.741 11.8
5/8=.607 14.5
11/16= .506 (not in the book?)
3/4= .428 20.7
Now the formula:
L=(A+D) x A x B x K
Remember to allow for a bit of space on the drum for uneven wrapping etc, unless you think you can wrap it perfectly everytime all the time? Also the machinery handbook lists specs on about 300 different cables, from 1/8 to 3", and various make ups and weave patters, I think I grabbed the 7x19 standard hoisting specs but I didn't write that down, There are by all means many variable with wire rope, please consult your local dealer about tonnage capacity and make up, this is purely meant to help with filling up yer spool...
for example a drum 8" wide with a barrel of 6" leaving 1" of free space, and flange diameter of 12" using 9/16 rope
First to find A 12-6-2x1 / 2 = 2"
now (2+6)x2x8x.741= 94.848 feet
Hope this helps I and I didn't confuse everyone... :P
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