Rohn specifies fine threads on their tower bolts (at least for Rohn
25), but no lockwashers. Presumeably this is because the nut on
a fine thread bolt has to turn farther to lose its preload and come
loose. I don't know what the torque specs are for Rohn 25, but the
steel tubing they use for the legs is soft enough that it will yied
slightly when you tighten up the bolts. In that sense, the tower leg
sort of becomes like a bellevue washer. Combine that springy
preload from the slightly deformed leg with a fine thread bolt and
you may not need a lockwasher. If you add a lockwasher, and
use the same torque as without the lockwasher, you probably end
up with less "squeeze" on the tower leg. Perhaps that "squeeze"
is intentional and desired.
This is all idle speculation of my part of course :) Best to ask the
manufacturer if you are not sure.
73 de Mike, W4EF............................
----- Original Message -----
From: <K8fu@aol.com>
To: <towertalk@contesting.com>
Sent: Wednesday, July 14, 2004 7:54 AM
Subject: [TowerTalk] Erections (TWR)
> Gentlemen.......................
>
> When I opened the pkg of bolts for my twr I noticed there were no
> lockwashers. Are these superfluous items or an oversight by the manuf ??
>
> Froggy...................
> Take a Frog To Lunch Tomorrow
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
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.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|