Cable Pulling Principles (cont'd)
Cable Pulling Forces (cont'd)
At the Sheaves
Sheaves are used to change the direction of the pull.
A change in direction creates a new resultant force that
may be greater than the cable puller's maximum pulling
force. This new resultant force exerts itself on the
sheaves, sheave anchoring system, and support struc-
tures illustrated.
The resultant amount of force depends on the angle of
the change in direction. A brief table is provided here.
Refer to "Calculating the Hook Load" to determine the
resultant force at any angle.
Greenlee / A Textron Company
Ultra Tugger
®
Cable Puller and Pulling Packages
Resultant Force Table for the Ultra Tugger
(22.3 kN or 5,000 lbs Maximum Pulling Force)
Typical Resultant Force at Sheave
Resultant Force=
17.1 kN 3850 lbs)
19
Angle of Change
Illustration
in Direction
180°
150°
135°
120°
90°
60°
45°
30°
0°
22.3 kN
(5000 lbs)
135°
4455 Boeing Dr. • Rockford, IL 61109-2988 USA • 815-397-7070
Resultant Force
in kN (lbs)
0 (0)
18.5 (4160)
27.4 (6160)
35.6 (8000)
50.2 (11,300)
61.6 (13,800)
65.8 (14,800)
68.7 (15,400)
71.2 (16,000)