LOSS CONTROL SERVICES
Wire Rope Clamps
Wire rope clamps or cable clamps are commonly used throughout the construction industry. There
are several different types of clamps and each has their own application. See manufacturers’ literature
for specific types and applications. They are used for rigging, temporary guardrail systems, securing
loads, and basically anything that involves cables. If these clamps are not used properly, they can lead
to the failure of any application. When using a cable clamp, your load capacity in any form is only 80
to 90 percent of the cable’s current strength. If the cable is new, its strength is easy to calculate, but if
the cable is old, rusty or damaged, the lifting capacity, holding capacity etc., is much more difficult to
gauge.
CABLES
Prior to each use, any cable or lifting device should be inspected by a competent person designated
within your company. The inspector should look for cables that have:
■ Broken wires/strands
■ Rust
■ Sand
■ Kinks
■ Any visible damage to the cable, eyes, etc.
If the damage covers more than 10 percent of the strands in one wrap or the lay of the cable is broken,
it should not be used for any application and should be discarded. See cable manufacturer for spe-
cific cable inspections. Inspections should only be made by a competent person designated by your
company.
CABLE CLAMPS
There are a variety of cable clamps and clamp manufacturers to choose
from. For cable clamp details and limitations, see the manufacturers’
specifications. If a clamp is used improperly, it can jeopardize its Correct
U-Bolt of All Clamps
application. Companies should never use malleable clamps in critical on Dead End of Rope
applications because they can bend, stretch or have other manufac-
turing defects. Only drop forged clamps should be used for critical
applications, such as guying, tie down or suspension.
Incorrect
Do Not Stagger
“NEVER SADDLE A DEAD HORSE”– Clamps
NEVER PLACE U-BOLT OVER THE LIVE LINE
The old saying “you never saddle a dead horse”
is true. Never apply a clamp with the saddle on the
dead side of the cable. Only the U-bolt should be Incorrect
U-Bolt of All Clamps
on Live End of
on the dead side of the cable, where crushing will Rope
Managing not affect the breaking strength of the hoist line.
Costs
through
Partnership
United Fire Group 118 Second Avenue SE Cedar Rapids, Iowa 52401 1-800-332-7977 ufgins.com
LC 7160 1014
FIVE STEPS TO INSTALLING CABLE CLAMPS PROPERLY
Apply first clip one-base width from dead end of wire rope with the
U-Bolt over the dead end. The live end rests in the clip saddle. Tighten
nuts evenly to recommended torque.
1. Apply second clip as close to loop as possible with the
U-Bolt over the dead end. Turn nuts firmly but do not
tighten.
2. Apply all other clips. Make sure to space the first two clips
evenly and keep all other clips six to seven rope diameters
apart.
3. Apply tension and tighten all nuts to recommended torque.
4. Check nut torque after the rope has been in operation.
For any cable clamp application to maximize its application, you
must determine the number of clamps, the amount of turn back
and the torque required for the size of the cable. As a reminder,
when using cable clamps, you will achieve 80 to 90 percent of
the cables working load.
See the following table for best results:
Clip Size Rope Size Minimum Amount of Rope Torque in
(Inches) (Inches) No. of Clips to Turn Back Ft. Lbs.
in Inches
1/8 1/8 2 3-1/4 3-1/4
3/16 3/16 2 3-3/4 3-3/4
1/4 1/4 2 4-3/4 4-3/4
5/16 5/16 2 5-1/4 5-1/4
3/8 3/8 2 6-1/2 6-1/2
7/16 7/16 2 7 7
1/2 1/2 3 11-1/2 11-1/2
9/16 9/16 3 12 12
5/8 5/8 3 12 12
3/4 3/4 4 18 18
7/8 7/8 4 19 19
1 1 5 26 26
1-1/8 1-1/8 6 34 34
1-1/4 1-1/4 7 44 44
1-3/8 1-3/8 7 44 44
1-1/2 1-1/2 8 54 54
1-5/8 1-5/8 8 58 58
1-3/4 1-3/4 8 61 61
2 2 8 71 71
2-1/4 2-1/4 8 73 73
2-1/2 2-1/2 9 84 84
2-3/4 2-3/4 10 100 100
3 3 10 106 106
3-1/2 3-1/2 12 149 149
References:
OSHA1926.251 Construction Industry Regulations
Crosby Group Wire Rope End Terminations
The information contained in this service bulletin was obtained from reliable sources.
However, United Fire Group accepts no legal responsibility for the correctness or completeness of this information.
LC 7160 1014
