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Chapter 6 Function Instruction
6.1 Calibration Function
In order to locate tested flaws accurately, parameter calibration must be
performed before test to guarantee incident point locates at surface of workpiece
(calibrate probe delay and X-value), sound velocity of workpiece matching up to
actual value (calibrate workpiece sound velocity), incidence angle of ultrasonic
wave accuracy (calibrate incidence angle). For providing customers with
convenience in parameter calibration, the instrument can realizes automatic
calibration operation automatically.
Calibration principle:
the instrument makes sound velocity and probe delay
calculations through arrival time (T1 and T2) of two echoes (B1 and B2) with
known sound path (S1 and S2).
Taking the CSK-
Ⅰ
A test block as an example, we will introduce three kinds
of calibration methods as follows.
6.1.1 Auto-calibration of Longitude-wave incident zero point
and Velocity of Normal Probe
The specific operation steps are as follows.
(1) Put the normal probe on the test block, and make sure the coupling is good.
Refer to Figure 6-1.
Figure 6-1 Velocity/Delay Auto-Calibration of the Normal Probe
(2) Adjust the test range twice than the workpiece thickness (>200.0mm), sound
