Ultrasonic thickness gauges are particularly useful for non-destructive measurement of wall thickness where access is only possible from one side of the test object, for example pipes or tanks. Most common engineering materials, such as metals, plastics and glass can be measured ultrasonically.
Ultrasonic Thickness Gauges work on a similar principle to sonar, except at far higher frequencies and speed. A transmitter sends a short pulse of ultrasound into the material. The pulse is reflected as an echo from the opposite surface of the material, returning to a receiver. The thickness gauge analyses the length of time the pulse takes to return in order to display the thickness.
Many building, construction and manufacturing companies have regulations surrounding the appropriate thickness of materials; gauges are used to accurately measure and check material thickness is at an optimum and standardised level to keep costs low, whilst providing adequate protection and quality.