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Re: Loose Bolts with DTI Washers

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    <<  Torque wrench readings are not accurate indicators of pretension,
unless the torque-pretension relationship is calibrated to the fasteners
being examined.  >>

Just wondering just how accurate torque readings are in relationship to bolt
tension.  Are they +/- 10 percent or perhaps +/- 20 percent?  Stated another
way, just how accurate do they really need to be given the, relatively, wide
range between minimum bolt tension and "necking down"of the bolt?  It would
appear to me that taking the upper limits of variation and using this as a
minimum torque reading would insure, at least, a minimum tension on every

Another query, why are "lock" washers or "split" washers, as they are
properly termed, not used between a hardened washer and the nut in cases of
vibration and cyclic loading? This method seems to be the accepted solution
to other applications where bolt loosening is a problem.  I have never seen
the RSCS address this solution.  Is there a reason why?

Jimmy  C.......(hisself)