In a message dated 10/18/2000 9:51:00 PM Eastern Daylight Time,
ccrobins@ktc.com writes:
<< If the stress is below yield there will be no loss of strength of the
bolt. In fact on the second application the preload may well be higher
because generally the friction lowers slightly on subsequent
applications resulting in a higher preload for a given torque. >>
Yes, if you finger tighten the nut it would be well below "yield" and I would
expect no loss of strength. But this "opinion" is in direct conflict with
the research presented by the Bowman engineers. Looks like a Chevy vs. Ford
thing to me. Fact is the loss of what the presenter called "preload" was
demonstrated at the seminar--this kind of negates the "opinions" as far as I
am concerned as does the information I posted earlier from the Bowman
technical publication. At any rate, I am gonna feel a lot better spending
the few cents it takes to replace critical fasteners when I disassemble.
Charley can keep his old stretched ones, and we both will be happy, I am
sure. My last post on the issue. 8^)
--David C.
"Do illiterate people get the full effect of alphabet soup?"
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