How the ultrasonic test works
The ultrasound is transmitted to the material under test in short pulses using a probe. The magnitude and time delay of the response is evaluated on the screen of the ultrasonic device, from which quite precise information about the location and dimensions of the defect can be obtained.
In order to perform ultrasonic testing, it is first necessary to provide surface preparation. Clean or grind off weld metal spatter, paint, loose scale and similar contaminants.