Determination Of Entry Angle Of The Probe; Determination Of Probe Arrow - NOVOTEST UD3701 Operation Manual

2. On the device screen multiple reflection echo appears. Find the maximum amplitude value.
3. Using gain, make two first signals exceed the standard level (the signal should be within screen
boarders, if necessary, use TVG).
4. Overlap А-gate on the first reflected signal, В-gate – on the second.
5. Output parameter values «La», «Lb» and «La-Lb» on the screen. Beam will be equal to calibration
block radius.
6. Make «La-Lb» value equal to 110 mm by changing parameter «VEL».
7. By changing parameter «DELAY» in parameter group «Probe» make «La» value equal to radius
of calibration block SО-3, according to the specification - 55 mm.
8. Repeat procedure of delay determination 3-5 times to get better accuracy.

2.5.3 Determination of entry angle of the probe

Determination of entry angle of the angle beam probe in А or B position (Figure 2.71). Moving of
angle beam probe near these positions, user seek maximum of the echo signal from the reflector
(cylindrical hole Ø 6 mm. located at a depth of 44 mm or 15 mm for the various positions of probes).
Value of the angle is specified on the marks of the corner scale opposite the output point of ultrasonic
beam.

2.5.4 Determination of probe arrow

To find output point "0" for ultrasonic beam of angle beam, put probe on the central mark "0"
(Figure 2.72) and by shifting motions find probe position, that is corresponding to the maximum echo
signal. Output point is located exactly above the center mark of the sample.
Arrow of the probe is defined in millimeters as a distance from the output point of the ultrasonic
beam to the end of the transducer body in the direction of scanning (measured by side scale in
millimeters).
Figure 2.70 – Setting the probe on calibration block SО-3
Figure 2.71 – Test block №2
Ultrasonic Flaw Detector NOVOTEST UD3701
Operation manual
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