Ultrasonic thickness gauges are the optimum tool for finding the remaining wall thickness of corroded or eroded metals such as found in steam and water piping, storage tanks, pressure vessels, etc. The ultrasonic thickness gauge measures the speed of propagation of the ultrasonic waves in the given material, and then converts this speed to the thickness.

It is completely nondestructive testing: No cutting or sectioning of parts is required, saving Equipment and labor costs.  Modern digital ultrasonic gages are highly accurate, repeatable, and reliable.