© PCE Instruments
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7.7
Effects of the material temperature
The material thickness and the transmission speed of ultrasonic waves are influenced by
the temperature. To achieve high measurement accuracy, measure samples of the same
material under the same temperature conditions. In case of steel, high temperatures
cause strong measurement errors (measured values are lower than the actual data).
7.8
Damping materials
Materials with fibres, pores and coarse particles cause strong scattering and energy
attenuation of the ultrasonic waves, resulting in abnormal readings or even missing
readings (usually the abnormal reading is lower than the actual thickness). In this case,
the material is not suitable for testing with this thickness gauge.
7.9
Reference examples
A material of known thickness or sound velocity is used to calibrate the meter. At least
one reference sample is required to calibrate the instrument. The ultrasonic thickness
gauge is equipped with a calibration block with a thickness of 4.0 mm
/ 0.16”. Refer to the
calibration instructions in chapter 8 of this manual for the calibration method.
8
Calibration (Cal)
8.1
Calibration instructions
a.
Press the back key when you are in the measuring interface, select
the menu item Calibration and confirm this selection with the OK key.
b.
The display will look as shown in the image to the right.
c.
During the measurement, the sound velocity is automatically set to
5900 m/s.
d.
Press the probe onto the calibration block to calibrate the meter.
8.2
Sound velocity calibration (V. Cal)
a.
Enter the submenu and select the item Sound velocity calibration
(V.Cal).
b.
The display will look as shown in the image to the right.
c.
As shown in the image, press the up and down keys to set the value.
d.
When the value has been adapted, press OK to complete the calibration.
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