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Written by Start a WISP Site Admin
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Tuesday, 22 November 2005 |
"We are looking at leasing some tower space. The tower is quite old, and
needs paint for sure. I looked at it, from ground level of course, and
it appears structurally good. I see no rust or any cracks, bulges, or
anything like that. The guys do appear to be looser than they should.
My question is how tight should they be? What is the best way to
tighten them? One side looks like the turnbuckles wouldn't tighten them
enough, but I could be wrong. The other two sides, I think the
turnbucles would do the job. Any hints?"
superdog1:
How tall is it?. Depending on the tower height and other variables, those guys probably shouldn't be tight. I would CAUTION
You against climbing anything You are not 100% certain is in perfect
working order. You are in OK, so when is the last time a twister of Oz
proportion "tested" this thing?
They are supposed to be a "little" loose. It would cause structural
failure if all of the guys were stretched tight. It is designed to have
some "give" in it to allow the pressure exerted on it to be applied
slowly and not instantly.
viperm:
Any time guy wires are loose or really tight there is possibly a problem and needs to have a proffesional check it out..
Stealthwave:
First what brand tower is it?
All towers have spec's on guy wire tension.
Rohn
25G is about 400 pounds of pull. You will need a Dyno to do it right.
We have installed our own towers. We rent the crane and get a Dyno from
a friend that pulls guy wires on his day job. The Dyno is tested
monthly. A guy tower will move a small amount not much. Even when we
finish with our towers. You can see a little sag in the wire.
The main thing is find out the brand and type of the tower to get the spec's.
slipstream1:
The guy wires will have a spec for the tension they should have in
relation to the tower. The proper way to tension the guy wires would be
with a dyno and a transit. You will want to make sure the tower is
plumb as well as tensioned. Most newer wires will have a color code on
the preform that will tell you what the size is and what the tension
should be. You should also be able to do a rebound test on the wires to
determine the tension of the wires. look on the internet and find out
the time it takes a wire to rebound from a hard hit on it with your
hand. You hit the wire and time the rebound. That time correlates with
the size of wire and will ball park the tension for you. Then you can
tell if it is close or loose.
davidg:
on smaller towers, a good rule of thumb is the guide wire is too loose if you can wiglle it and create a snake up the wire.
also,
on hot days the wire will be loose, while on cold days it will be
tight. the trick to tensioning the wire is not to tighten it so much
that it causes a failure during extreme cold.
this is NOT a job for the inexperienced. all sides have to be equal.
nunya:
On a 90' tower, I wouldn't imagine the guys having very much slack. There should always be some
equally distributed tension. On any "large" towers I've seen erected,
there was a survey spotter involved, along with a "hugemongus" meter at
each termination point.
Usually the engineer or manufacturer designates the guy tension and size on the prints. Are there prints on site or available?
If
you notice more slack on one side or leg than another, that should
sound an alarm bell in your mind. How many guys terminate at each point
on the ground?
Original thread location
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Installation Techniques 
