Is this a strong way to install a guy wire to support a telephone pole?

  • #1
HRG
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stay wire guying for telephone pole
I watched workers install a guy wire to support a telephone pole today. The method used was a single guy wire that just had the two legs of the stay wire wrapped around the single guy wire and that' it. Why won't the guy wire just be pulled out from the stay wires?

To illustrate, see 1:08 in the following youtube video:
Stay Wire Guying on Telecommunication Pole Installation.

Note how the stay wire is looped through the eye and then the two legs are just wrapped around a single guy wire.

It's mind boggling to me why the single guy wire will not just pull out from the stay wires over time.
Can anyone explain how it can be permanently strong?
 
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  • #2
Although I haven't inspected local installations (they are well covered & hidden), there seems to be two concepts behind it.

1) The twists of the strands of the stay wire match those of the guy wire. That way the strands of each fall between the surface strands of the other.

2) "Chinese Finger Trap" approach. https://en.wikipedia.org/wiki/Chinese_finger_trap

Cheers,
Tom
 
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  • #3
HRG said:
Can anyone explain how it can be permanently strong?
Yes. It decomposes topologically into a Flemish eye, or Dutch splice, which has a similar strength to the cable, and does not require the free ends to be buried with a marlin spike.
https://en.wikipedia.org/wiki/Wire_rope#Eye_splice_or_Flemish_eye

It works with a cable made from six solid wires and a core, but not so well with flexible wire rope, as the external ends then require wrapping and mousing to prevent them unwinding.

The advantage of the separate "hairpins", is that the plastic bends placed in the short hairpin cables, used for the splice, can be made in a press before the required wire length is known. The bent hairpin is split, making two, which also conveniently eliminates the tail of the equivalent dutch splice without burying.

Since the hairpins are made from the same cable as the stay wire, the internal diameter of the outer helix is less than the outer diameter of the cable. That guarantees a permanent pressure on the wire. The helix of the wire is the same pitch and hand as the helix of the folded hairpin, so the pitch of the hairpin matches, and locks into the grooves of the cable when the wire is first tensioned.

The splice becomes a helical form of the capstan equation, with the turns around the capstan being the turns of the helix around the inner cable.
https://en.wikipedia.org/wiki/Capstan_equation
 
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  • #6
There is a very much quicker way to insert a temporary loop into the end of a flexible wire rope. It does not involve threading the ends through the cable.

It involves discarding the core, while splitting the rope into two bundles. The two bundles are then counterintuitively opposed through or around the eye, before being wound back together, which leads to a full loop that will lock at the eye. The long ends are then wrapped together, which makes a stray tail, that looks like the original rope tail where it hangs down, because that is exactly what it is.

Practice making that loop, because only then will you understand it, and so be able to form it, with your eyes shut, when you really need it in an emergency.
https://www.instructables.com/Really-quick-wire-rope-eye-splice/
 
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  • #7
Tom.G, Baluncore, Filip Larsen, Jack action and Baluncore,

Thank your for your responses. Appears that the method works, though it still seems mind boggling
 
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