How To Make The DAC Curve Of Ultrasonic Flaw Detector?

Ultrasonic flaw detector is a common and widely used testing equipment in non-destructive testing instruments. The DAC curve of ultrasonic flaw detector is available in all models today. How to make the DAC curve of ultrasonic flaw detector is roughly divided into the following steps:
Step 1: Select the DAC function group, select the setting menu, and set the display status function to "on".
Step 2: Select the calibration menu, place the angle probe on the RB-3 test block, conduct detection on the 10MM·○3 through hole on the surface, reflect the echo, select the A gate start function, and adjust the A gate start and A gate width , so that the reflected echo is located in the gate (the echo must be within the range displayed on the screen, generally 80% of the full screen), then select the save calibration function, turn the dial clockwise, and the saved calibration value will be changed from 0 to 1 automatically .
Step 3: Use an inclined probe to find the reflected echo of the 20MM·3 through hole on the RB-3 test block, select the initial function of gate A, adjust the initial gate position with the dial to catch the reflected echo, and select Save the calibration function, turn the dial clockwise, the saved calibration value will be changed from 1 to 2 automatically, if the calibration value is wrong, press the save calibration function and turn the dial counterclockwise to save the calibration point again.
Step 4: Use an inclined probe to find the reflected echo of the 30MM·3 through-hole from the surface on the RB-3 test block, select the initial function of gate A, adjust the initial gate position with the dial to catch the reflected echo, and select Save the calibration function, turn the dial clockwise, the saved calibration value will be changed from 2 to 3 automatically, if the calibration value is wrong, press the save calibration function and turn the dial counterclockwise to save the calibration point again.
Step 5: After the calibration of the calibration point is completed, check whether the displayed DAC curve is accurate on the comparison test block. If there is an error between the calibration point and the drawn DAC curve, select the correction menu.
Step 6: Compensation - Select the compensation menu. If there is a difference in the material attenuation value of the measured workpiece and the comparison test block, please calculate the material attenuation value and input the material attenuation function. The surface compensation function refers to the measured workpiece and the comparison test block. When the surface roughness and curvature are different, please calculate the surface compensation value and input it into the surface compensation function.
Step 7: Evaluation, input -4DB in the judgment line 1, enter -10DB in the quantitative line, and enter -16DB in the evaluation line. Since this flaw detector supports the curve creation of JIS standard, there are initially five DAC curves. If you need to reduce the number of curves to 3, you only need to set the evaluation line 1 to the same positive and negative DB number and the waste line 1, and the waste line 2 to the same positive and negative DB number, then press the DB key , improve the DAC curve to a position suitable for observation.
Step 8: Save the data, return to the function group, select the data menu to save the data, and the DAC curve is created.