Regarding the misguided recommendation posted last week that
Guy-Grips be used on tower guy wires, the Preformed Line Products
web site specifically recommends use of Big-Grip preforms on
guy wires used on steel towers.
www.preformed.com
The web site further states that Guy-Grip dead-ends are intended only
for use on guy wires of total length not exceeding 70 feet used on wood
poles associated with power line distribution.
The web site cautions that tower owners must maintain required minimum
guy tension of 10% of breaking strength to avoid pre-mature Big-Grip
failure resulting from flexure of the dead-ends caused by exposure to wind
forces over many years. They recommend annual guy tension measurement
of all guy wires utilizing Big-Grips and retensioning if required.
As an aside, every tower owner should perform annual inspections of
tower and guy foundations, guys, guy attachment hardware and the
overall tower structure, even if guys do not use incorrect dead-ends.
Serious problems should be corrected immediately and routine problems
should be corrected when practical and reasonable. Late Fall is an
excellent time for tower inspections, when antenna projects are on hold
until spring, and before severe Winter weather has begun.
The British Ministry of Defence prohibits use of Guy-Grips on steel towers
but recommends the use of Big-Grips. For pre-existing steel towers using
Guy-Grips, the MOD requires annual inspection of Guy-Grips for slippage:
www.defence-estates.mod.uk/publications/technical_bulletins/2000/tb_00-15.pd
f
73!
Frank
W3LPL
donovanf@erols.com
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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