> [jim] In a tower application, holding sections together, I would think that
> you're loading the bolt only in shear, so how "tight" the bolt is isn't
> all that big a deal. A pin and cotter key would probably work almost as
> well. As would a jam nut. Basically anything to keep the bolt from
> falling out.
> .
>
> (The bolt at the bottom of the base of a self supporter keeping it from
> falling over are another story.. they ARE loaded in tension)
> _______________________________________________
>
>
?
The title said "self supporter" so I was assuming no guys. Even with
guys there would be some deflection/oscillation so I would think you'd
want the joint to not slip..i.e. not have it depend on bearing on the
bolt because you'll get wear on movement.
You can see no guys here: http://www.tacocommunications.com/Wade/DMX.pdf
So the intermediate joints see the same stuff the bottom does...just less.
Still seems like this wants to be a joint that works due to
friction..high clamping force. It's a flat steel joint. I would think
you really want no movement.
hardened steel washers on both sides are good for spreading the clamping
force away from the hole too. (make sure thick enough)
Sounds like maybe the main issue is all the bolts in the tower might be
non-optimal? Are they even 307A?
If you can't torque the bolts beyond a certain clamping force, then you
could analyze the load created by the tower and decide if the joints move.
If the joints move, then you can see why have a loosening problem.
But if you have moving joints, you still have an issue even if you fix
the loosening problem. But depending on the situation, you might decide
that's okay or that it's rare they would move.
-kevin
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