>Stainless steel bolts are not as strong as the SAE 5 grade bolts
>that Rhon uses.
>
>SAE Grade 5 bolts are 120,000 psi UTS (ultimate tensile strength)
>
>A typical stainless steel bolt is rated at about 90,000 psi UTS
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I certainly can't argue with the figures above that were placed on
the Reflector.... but somehow I just can't get it through my thick
skull why that makes any difference. The UTS of 90,000 psi is not
being challenged on my tower, to my knowledge. The guys, anchored
by 4,000 lbs of concrete would probably IMO keep the tower upright
with no bolts at all, after once installed. Surely, 90,000 lb
tensile strength bolts will keep the tower sections together.
Admittedly, I am a retired electronic engineer and not a structural
engineer but I do declare that I can't for the life of me see what
difference in a tensile strength of 90,000 or 120,000 makes in that
application.
This is not a flame: it is an earnest effort on my part to have
someone who is knowledgeable explain to me (and perhaps there are
others that would like an explanation) where the difference comes
into play and how it affects the life/stength of the tower as it
is installed (with the legs overlapping as they do on Rohn 25G).
Again, I believe that I'd a sight rather see a 90,000 psi tensile
strength stainless bolt that is still 90,000 psi after 10-20 years
than a 120,000 psi tensile strength steel bolt that is actually
rusted through before 20 years (and don't tell me that doesn't
happen in Florid! I've taken down some old Rohn down there!!!)
If I need to be enlightened, please enlighten me!!
Rod, W5HVV
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