YUSHI INSTRUMENTS
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the sound path distance of the calibration block, at this point, the sound velocity is the sound velocity of
the material.
4.3 Calibration of the Angle Beam Probe
Concerning the contact detection by angle beam probe, distance calibration is a must before any
detection task. There are various kinds of angle beam probes with different structures and sizes, and
different detection objects require different K values, thus the sound paths in wedge blocks are not same,
in other words, the front edge length of each angle beam probe of transverse wave should be measured to
decide the zero-bias value. Along with the probe abrasion during the usage, the angle beam probe need
recalibration after a period time of usage.
4.3.1 Calibration Procedures
Set the sound velocity and sound path of the material known on the parameter menu, primary echo is
adopted generally.
Calibration of the front edge of the probe;
Calibration of the zero of the probe;
Calibration of the probe K value (angle).
4.3.2 Operation Steps
Calibration of CSK-IA as an example
：
1. Press
to enter the parameter menu, press
(up) or
(down) to select the sound
path submenu. Then press
(left) or
(right) to set the value as 125mm.
2. Press
(up) or
(down) to select the sound velocity submenu. Then press
(left)
or
(right) to set the value as 3240m/s.
3. Calibrate the front edge of the probe: put the probe on the test block and move it till the reflector echo
of the hollows of R100mm reach the highest level, measure 89mm of the front face of the probe with a
ruler, at this point, the front edge value of the probe is: 100-89=11mm. As shown in Figure 4-4, after that,
press
to enter the probe menu, then press
(up) or
(down) to select the probe front
edge submenu, press
(left) or
(right) to set the probe front edge value as 11mm, as
shown in Figure 4-5.
Figure 4-4