In a message dated 96-06-20 03:03:33 EDT, you write:
>I have a question regarding tensioning guy wires and keeping the tower plumb
while >this operation is being performed.
Hi, Walt --
I'm only going to comment on part of this and let the engineers out
there address the finer points.
>
>About a year ago I put up 90' of Rohn 55G guyed with 1/4"
>EHS. The tower was plumbed during and after erection.
>The guy wires have some play in them and need to be
>tensioned to the recommneded 10% of breaking strength,
>or 650#. I got a Loos tension guage and will be ready
>to take on this chore in the very near future. Does
>anyone have any suggestions as to how to perform the
>tensioning (the order), and how to preserve the plumbness
>of the tower. Should I tension all the guys to some
>intermediate, arbitray, tension, like 200#, and then
>repeat the process until the desired tension is achieved.
>
First of all, the TIA-222 tower spec allows a tolerance of 1 part in
400 for tower alignment; that's 3 inches per 100 feet so your tower doesn't
have to be perfectly plumb. Start with the bottom set of guys and the
intermediate tension that you mentioned, verify the plumb (or pull into
plumb) and then adjust to the final tension. If all the guy anchors are at
the same level, you only have to measure one guy; they should all be the
same. Once you've got your intermediate tension and plumb, it doesn't take
much travel in the turnbuckle to get to the final tension - maybe as little
as 1 turn so there's not much problem with pulling the tower out of plumb.
Move up to the next set and repeat until finished.
73 and good luck, Steve K7LXC
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