Tritex Multigauge 5700 Datalogger Ultrasonic Thickness Gauge www.tritexndt.com
Page 52
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The correct couplant should be used.
Although we recommend
couplant specifically designed for taking measurements, other liquids
can be used such as liquid soap, wallpaper paste, water and some
hand cleansers. Grease is not a good alternative.
q
Remove debris from the probe face between measurements.
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Sometimes it is necessary to rock the probe slightly and gently
in order to obtain measurements.
This often helps the probe to
receive echoes from the back wall.
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Ensure the coating is not layered or does not contain foreign
objects in its construction.
Layered coatings cause reflections at the
layer interface. This seriously weakens the strength of the ultrasound
and may prevent it from travelling all the way through. The same
applies to foreign objects which can deflect the ultrasound path or
prevent the ultrasound from passing.
q
Some types of casting may cause problems for ultrasonic
gauges.
Castings can contain foreign elements within their
construction and they also have varying velocity of sound properties
throughout their structure. This may result in inaccurate
measurements due to the inherent inconsistencies in the material.