DeFelsko PosiTector UTG v.3.1 Full Manual User Manual
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Flaws, voids or pits
A void or flaw inside a metal object is better detected in SE mode
where the Gage will measure the distance from the surface down
to the flaw. Scan-mode will help locate the flaw. In ME mode the
Gage may not “see” the flaw and will display a thicker, total
thickness value.
Measuring the depth of a rod
ME mode may produce accurate results in situations where SE
mode may not be able to measure at all.
Probe pressure
Applying too much hand pressure on the probe while measuring
may squeeze out too much couplant and make it difficult for ME
mode to effect a measurement.
Temperature
Probe temperature: ME values are not affected by temperature
changes within the probe. But the Gage should be zeroed (pg. 10)
for best accuracy when operated in SE mode.
Metal temperature: Sound waves travel faster when the material is
heated. Preprogrammed sound velocities within the PosiTector
UTG are valid for normal temperatures in the vicinity of 15°C and
must be adjusted for extreme temperatures. For best results in
either mode, the Gage should be adjusted to the known thickness
of the material at a temperature similar to the part being measured.