Ultrasonic Wall Thickness Measurement
Ultrasonic Wall Thickness Measurement is a non-destructive testing technique that can be used to determine the thickness of pipe walls.
"Ultrasonic thickness gauges measure the thickness of a part by measuring the time sound travels from the transducer through the material to the back end of a part, and then measures the time of reflection back to the transducer. The gauge then calculates the thickness based on the velocity of sound through the material being tested."