Lead Gauge Cal 7
Lead Gauge Cal 7
Lead Gauge Cal 7
1.0 PURPOSE
2.0 APPLICATION
2.2 This procedure applies to the initial calibration of newly acquired gauges
and to the periodic recalibration at the specified intervals.
4.0 PROCEDURE
4.1 Field inspectors shall calibrate their lead gauges at least every 6 months as
outlined in this procedure.
4.2 Using thumb and index finger, depress the moveable contact point slowly
and evenly over the full range, slowly allowing the contact point to return to
the starting position. The indicator pointer shall move freely { without
binding} and should return to the same starting position.
4.3 Visually examine gauge for any obvious defects which would affect function
or accuracy of gauge. If any defects are observed , refer to paragraph. 4.14
for remedial action.
4.4 Install the proper contact points on the lead gauge so that the gauge can be
measured over 2”.
4.5 Place the contact points in the notches 2” apart in a 2” TPF lead gauge
standard. Adjust the lead gauge to read zero and adjust the gauge.
4.6 Transfer the lead gauge to a 3” TPF standard and observe the reading. The
lead gauge should read 0.0085” +- 0.0005 fast.
4.8 Place the lead gauge in the 3” TPF standard and readjust the gauge to read
zero and lock the gauge.
4.9 Transfer the lead gauge to the 2” TPF standard and obseve the reading. The
lead gauge should read 0.0085” +- 0.005” slow.
4.12 Any lead gauges exceeding specified tolerances per paragraph 4.6 , 4.9 and
4.11 at any time during calibration , shall be returned to inspection services
for repair.
5.0 DOCUMENTATION
5.1 A record of field calibration shall be send to main office . The record shall
include as a minimum, the following information.