MARK J WEATHERS wrote:
> Here's my 2 shillings (farthings?) worth:
>
> While torquing a fastener too close to the yield point may be detrimental,
> fatigue life probably goes down if the fastener is undertorqued as well. You
> do not want the fastener system be stetching and unstretching under load
> cycles, as this cycling generates fatigue problems, it has to be clamped and
> stetched enough to keep everything still.
True, too. But, I wasn't adressing that problem--in fact, the engineering
process I described ensures a clamp load at
least 1.5 times the greatest expected load at a little more than half the yield
of the fastener.
It's very true, though, that improperly designing for a clamping load barely
equal to the actual load invites failure
due to cyclical loading--and that includes impulsive loading and vibration
loading. The up and down vibration of an
inline engine is something to behold. (!)
Cheers.
--
Michael D. Porter
Roswell, NM
Never let anyone drive you crazy when you know it's within walking distance.
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