YUSHI INSTRUMENTS
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are available, other functions will be locked and unavailable.
Chapter 4 Application of Testing
4.1 Calibration Method and Steps of the Instrument
Before you use YUT-2620 to test the work piece, you should first calibrate the instrument:
according to the material, size of the work piece to be tested as well as the relevant standards, choose the
appropriate test method and probe, set the sound velocity, sound path of the material, set the working
frequency and other instrument parameters as well as the probe parameters, and adjust the probe zero.
First, according to the relevant industry standards or the requirements of the site, decide the test
method and choose the appropriate probe.
4.2 Zero Calibration of the Straight Beam Probe
Concerning the contact method measurement by the straight beam probe of the general flaw
detector, generally speaking, there is no emphasis on zero-bias control, as long as you aim the start pulse
at the left side line of the display grid, any zero-bias can be ignored, this is acceptable in most cases.
However, concerning the contact probe with a protective foil, owing to the time delay in the protective
components, there might be a considerable zero-bias which affects the measurement of the the distance
accuracy. In order to position the flaw to be tested, you should make a distance calibration before the
measurement.
4.2.1 Calibration Procedures
In the parameter menu, set the sound velocity of the material given. If the sound velocity of the material
is unknown, you should measure the sound velocity value of the material first. (Measurement of the
sound velocity of the material)
In the parameter menu, set the sound path.
Put the probe on the calibration block (take CSK-1B) test block as an example, as shown in Figure
4-1), the coupling is favorable.