Loos and Company Technical Information

Loos and Company Technical Information

Technical Information


By   Loos & Co., Inc.


Cable Diameter Related to Pulley or Sheave Diameter

The service life of cable and wire rope can be increased if (1) it operates over the largest possible pulley or sheave diameter, and (2) it is properly supported in the pulley or sheave groove. The working life of the individual wire strands is greatly reduced as the pulley or sheave diameter is diminished. The chart below shows minimum tread diameters over which various sizes and constructions of cable should operate.

Minimum Tread Diameter for Pulleys or Sheaves

Ratio of cable diameter to pulley diameter

Desirable Minimum

Critical Minimum

42:1 24:1 12:1 28:1 18:1 10:1

Cable Diameter

in Inches

6x7
or
7x7

6x19
or
7x19

6x31
7x31
6x37

6x7
or
7x7

6x19
or
7x19

6x31
7x31
6x37

1/16 2-5/8 ---- ---- 1-3/4 ---- ----
3/32 2-15/16 2-1/4 ---- 2-5/8 1-11/16 ----
1/8 5-1/4 3 ---- 3-1/2 2-1/4 ----
5/32 6-9/16 3-3/4 ---- 4-3/8 2-7/8 ----
3/16 7-7/8 4-1/2 ---- 5-1/4 3-3/8 ----
7/32 9-13/16 5-1/4 ---- 6-1/8 4 ----
1/4 10-1/2 6 3 7 4-1/2 2-1/2
5/16 13-1/8 7-1/2 3-3/4 8-3/4 5-5/8 3-1/8
3/8 15-3/4 9 4-1/2 10-1/2 6-3/4 3-3/4
7/16 18-3/8 10-1/2 5-1/4 12-1/4 7-7/8 4-3/8
1/2 21 12 6 14 9 5