Jeamar Winches Product Catalog

Lifting with Multi-Part Line

How to calculate Line Parts

Number of Parts
of Line		 Ratio for Bronze
Bushed Sheaves		 Ratio for Anti-Friction
Bearing Sheaves
1 .96 .98
2 1.87 1.94
3 2.75 2.88
4 3.59 3.81
5 4.39 4.71
6 5.16 5.60
7 5.90 6.47
8 6.60 7.32
9 7.27 8.16
10 7.91 8.98
11 8.52 9.79
12 9.11 10.6
13 9.68 11.4
14 10.2 12.1
15 10.7 12.9
16 11.2 13.6
17 11.7 14.3
18 12.2 15.0
19 12.6 15.7
20 13.0 16.4
21 13.4 17.0
22 13.8 17.7
23 14.2 18.3
24 14.5 18.9
     
1 part of line
 2 parts of line
 3 parts of line
     
4 parts of line
 5 parts of line
Total Load to be Pulled  
-------------------------------------- = RATIO
Single Line Pull in Pounds  

Example:
To find the number of parts of line needed when weight of load and single line pull is established.

Sample Problem:

72,480 lbs. (load to be lifted)  
------------------------------------- = 9.06 RATIO
8,000 lbs. (single line pull)  

Refer to ratio 9.06 in table or number nearest to it, then check column under under heading "Number of Parts of Line" ... 12 parts of line to be used for this load.

Example:
To find single line pull needed when weight of load and number of parts of line are established.

Sample Problem:

68,000 lbs. (load to be lifted)  
-------------------------------------- = 10,300 lbs.
6.60 (ratio of 8 part line) (single line pull)

10,300 lbs. single line pull required to lift this load on 8 parts of line.