[Bell Historians] A bell frame problem

[Bickerton, Roderic K (SELEX) (UK)]

Mild steel starts to go plastic at around 56000 lbs/sq inch, 500 cwt/sq inch.
Stainless is available in a lot of different grades, and each grade is available between annealed and full hard.
301 stainless is about 30000 annealed to 140000 full hard
It would appear that the normal for an I section beam is grade 304 annealed normally at a yield of 31200 lbs/sq inch.
That is only a little over half the strength of MS. Young's modulus is also down similarly, so deflection for a given load will increase. Stainless also has a higher expansion coefficient than MS, which matches stone or concrete well.
Not the ideal material and a bit expensive.
 
 
Information on buried pipe work suggests that there is little difference in corrosion rates of the various ferrous materials in a wet corrosive soil, so if the tower is a very wet one, perhaps stainless wall cleats with steel RSJ's may be worth a look, stainless and steel fairly close on the electro chemical table, (0.25V) so the corrosion problem at the interface is not excessive, but should be protected.
 
 
 

________________________________

From: bellhistorians at yahoogroups.com [mailto:bellhistorians at yahoogroups.com] On Behalf Of Andrew Aspland
Sent: 27 March 2007 14:46
To: bellhistorians at yahoogroups.com
Subject: Re: [Bell Historians] A bell frame problem


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Is stainless steel suitable - is it as strong as mild
steel?
Sounds to me like the lowest set of beams could be
rolling to and fro as the beams above push and pull. 
Rather than try to replace the single bolts how about
some system of anchoring all the intersections of
beams so that the rolling is reduced - possible
anchoring the ends of the lowest beams into the walls.
Resting on corbels does not prevent the rolling!
Andrew




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