Katronic Technologies FLUXUS ADM 6725, Operating Instruction

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12 - 6
ADM 6725 E10

KAT
Wall Thickness Measurement
Note:
•
As soon as the first measuring value is obtained, a short acoustic signal sounds,
and a tick sign appears in the upper display line.
•
FLUXUS displays the last measuring value which was obtained. The measured
value will not be lost whilst the probe is taken off the material.
•
The question mark near the unit of measurement and the red SIGNAL-LED show
that no measuring value can currently be obtained.
E NT E R
•
Finishes the measurement run and
•
stores or outputs the measured value if
requested.
BR K
Returns to the MAIN MENU of the WTM option.
12.5.4 Measurement Failure
•
Take the probe off the test piece (the pipe).
••••
If necessary, clean the probe and the area of
the test piece where the measurement takes
place.
•
Apply a film of acoustic coupling component
onto the test piece and/or the probe.
•
Firmly press the probe against the test piece.
•
Cancel measurement by pressing
BR K
in case
of repeated failures. Start calibration again.
Note:
Calibration and the actual measurement must be carried out under similar acoustic
coupling conditions:
•
Use a small amount of coupling component. The coupling component must be
applied in the same way each time to avoid errors caused by different film
thickness.
•
Apply constant pressure when pressing the probe against the test piece.
12.5.5 Possible Reasons for Incorrect Measuring
Results
Temperature fluctuations
These change the sound velocity of the material.
Doubling effect
Wall thickness measurements using an ultrasonic method suffer under certain
conditions from a phenomenon called 'doubling effect'. This means, that the
measured value is in fact twice (or sometimes three times) as big as the actual
thickness of the material because of unwanted reflections of the sound signal.
This effect can be observed in situations where the thickness of the material is less
than the lowest measuring range of the probe.
Measured value is too small
Should FLUXUS display a value considerably smaller than expected, a material
defect might be the reason for this. The material defect, not the boundary layer of
the material, could have caused a reflection of the ultrasonic signals.
Surface condition