What is an Ultrasonic Thickness Gauge?

An ultrasonic thickness gauge is a non‑destructive testing (NDT) instrument used to measure the thickness of a material by using ultrasonic waves.

The basic principle is:

- A probe sends ultrasonic waves into the test object.
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- The waves travel through the material, reflect from the back surface, and return to the probe.
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- The instrument measures the time taken for the waves to travel back and forth and calculates the thickness using the sound velocity in the material.

Key advantages:

- Non‑destructive: does not damage the test object.
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- Can measure from one side only (e.g., pipes with internal corrosion accessible only from the outside).
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- Fast and relatively accurate.
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- Suitable for metals, plastics, glass, ceramics, and other materials.

2. Typical Application Fields

Common application areas include:

1.