Ultrasonic Testing (UT) is completely nondestructive. The test piece does not have to be cut, sectioned, or exposed to damaging chemicals.
Access to only one side is required, unlike measurement with mechanical thickness tools like calipers and micrometers. There are no potential health hazards associated with Ultrasonic Testing, unlike Radiography.
When a test has been properly set up, results are highly reputable and accurate.
How It Is Used
Ultrasonic Testing uses (ultra) sound to detect internal discontinuities.
Ultrasound can be used on almost any material to locate discontinuities from large disbonds down to the smallest defects. It can also be used to measure the overall thickness of a material, and the specific depth of a defect.
A common example of an ultrasonic thickness measurement, which would be to monitor erosion of pipes and tank wall for integrity.