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Re: Bolt Tightening

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    <<  Also, the turn of the nut method requires "calibration" using a
device such as a Skidmore-Wilhelm Bolt Tension Calibrator.  >>

I believe you to be wrong in this premise.  The turn of the nut from snug
tight to 1/3-1/2 more turn is used in lieu of a Skidmore-Wilhelm type
device.  I have used the turn of the nut method on many steel erection jobs
and never had an inspector turn it down.  Usually 10 percent of bolt groups
are checked with a torque indicating wrench by the inspecting authority.  A
tensioned bolt is a tensioned bolt regardless of the means used to achieve
that end.

I have found the calibrated air wrenches to be extremely sensitive to the
consistency of the air supply employed.  Distance from the compressor or air
receiver, efficiency of the compressor and even temperature can effect the
desired result.

Short of a wring-off type of bolt I have found that the tension indicating
washers afford the greatest amount of confidence to an ironworker along with
comparative ease with which they can be inspected and verified.

When I retire I intend to offer pre-flattened tension indicating washers to
the construction industry.  <G>


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