There are several ways to terminate a wire rope cable and not degrade
the breaking strength. Grips are one. Cable clamps or clips are not
one. The inside of the grip wires are coated with an abrasive which aids
in the grip. Hence, they are generally considered a "one time use"
product. A problem with clamps/clips is insuring proper spacing,
orientation and the nut tightened to the specified torque, and then
re-torqued as the assembly relaxes a bit. Hence, variability in
retention strength occurs. If you've tried to hold a wire rope and
tighten the clamp/clip nuts you understand the problem ie Crosby
specifies 30 ft-lbs for 3/16 and 1/4 wire rope clips.
Clamps are mostly obsolete in commercial use, if you see them on a power
pole guy they probably were installed sometime last century.
There are easily millions of grips in use, certainly hundreds of
thousands just on ham towers.
A Klein cable grip (aka "Chicago Grip") is used to provide temporary
tension when needed on a wire rope guy. google it
Grant KZ1W
On 1/7/2016 10:49 AM, dw wrote:
I'm trying to understand the use of pre-formed wire-wrap dead-ends for
guy-wires.
If I understand the install process, the guy-wire itself doesn't wrap
around the lower anchor fixture.
But the dead-end goes into the lower anchor fixture and the dead-end
then wraps around the guy-wire.
First the guy-wire tension is pulled up to pre-tensioned position.
Then the dead-end is fed through the anchor fixture.
Then one leg of the dead-end is wrapped around the guy-wire...either
wrapped all the way or part way.
Then the other leg of the dead-end is wrapped.
And then the wrapping is complete....I think that approximates the
installation steps.
The question I have is, what is supposed to keep that wrapped dead-end
from slipping off the guy-wire?
Hard for me to believe it will grip the guy-wire just being wrapped
around it, especially when the guy wire is fully tensioned.
Why not put forged guy-wire clamps around the dead-end after its wrapped
to ensure it won't slip off the guy-wire?
What am I missing?
Also, companies like Hubbell and AED manufacture straight-type bolt-on
clamps that come in different lengths....like 6 inches with 3 bolts.
How does the bolt-on clamp assembly compare to the dead-end, in terms of
reliability and pull strength?
Thanks!
N1BBR :-]
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