> At 22:36 11/10/99 , Stan or Patricia Griffiths wrote:
> > I have to believe the bolts support a good deal of the downward
> > force in shear.
> ===========================>
> Upward force, as well.
>
> > I do believe that squeezing the tower leg prevents the need for a
> > lock washer, however. I have never heard of nuts falling off of
> > tower leg bolts or a tower leg bolt actually
> >breaking and/or falling out.
> ==============================>
> Good grief, no need to ever tighten the hardware so much that the tubes
> are deformed. If you do, you have probably exceeded the allowable
> percentage of yield values on the bolts.
> Additionally, the flat washer additions and lock washer additions are
> not necessary unless you want to tighten all hardware to proper bolting
> torque values, and if you want to minimize any possibility of harm to
> the galvanized tower surface.
> Regardless of how it is done, I agree that it is hard to imagine a bolt
> breaking from shear, or a nut coming off in a tower leg bolt application.
>
I have been around several Rohn experts; maybe Steve can comment on
this also.
There is no necessity to put any additional hardware on the tower other
than the bolts and nuts that come with the tower from Rohn. The fine
threads were chosen to prevent the nuts from coming loose.
I am still cringing at the discriptions of those guys "showering down" on
the bolts with the wrenches. You just put enough torque on the bolts to
securely tighten the nut into the tower leg. no more torque than a normal
man can exert with two small open-end wrenches.
The majority of the weight of the tower is supported by the bottom of
each section resting on the top of the section below it. The bolts are
to hold each leg firmly in place, and to keep the legs from twisting left
and right. By immobilizing each joint, each leg handles 1/3 of the load.
You can spot over-torqued sections very easily. If the leg is no longer
perfectly round, too much elbow grease was used when it was installed.
As for pal nuts...these come with, and are required on all the guy brackets
and torque arms.
Before the flames start, this ain't me talking; this is what I have picked up
in 40+ years of asking questions to knowledgable people.
IMHO, I think that using any other kind of bolts is not a good idea at all.
(((73)))
Phil, K5PC
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