An ultrasonic thickness gauge is a device used to measure the thickness of
materials using ultrasonic waves. It is commonly employed in industries like
manufacturing, metalworking, shipbuilding, and aerospace to non-destructively
measure the thickness of materials such as metals, plastics, composites, glass,
and ceramics.

Applications:

1. Industrial Inspection: Ultrasonic thickness gauges are
   commonly used to inspect the thickness of pipelines, tanks, boilers, and
   other equipment to detect corrosion or wear.
2. Aerospace and Automotive: Used to measure the thickness
   of materials in aircraft, cars, and other vehicles to ensure safety and
   integrity.
3. Manufacturing: In production lines, ultrasonic gauges
   ensure materials like plastic, rubber, and metal components are of the
   correct thickness.
4. Shipbuilding: Critical for checking the thickness of
   ship hulls and other structural components exposed to harsh marine
   environments.

Advantages:

• Non-Destructive: Measurements can be made without
  damaging or altering the material.
• Versatile: Can measure a wide range of materials, from
  metals to plastics.
• Precise: Offers high accuracy and repeatability, making
  it reliable for quality control and safety inspections.

Limitations:

• Surface Preparation: The surface needs to be clean, and
  sometimes a coupling gel is required to ensure proper contact between the
  transducer and the material.
• Material Dependency: The speed of sound varies between
  materials, so the device must be calibrated for the specific material being
  tested.

An ultrasonic thickness gauge is a powerful tool for maintaining the
structural integrity of equipment and ensuring product quality without damaging
the workpiece.