Thickness gauges are handheld devices used to measure the thickness of an object, or the thickness of a coating on an object in some cases. Thickness gauges can be used to measure the thickness of walls in a building or the thickness of pipes in a plumbing or heating system. Knowing the thickness of metals can be important in careers like engineering. The thickness of a metal can provide information on the metal's tolerance. For instance, corroded materials might have a reduced thickness, and procedures that could be performed on sturdier metals could fail when used on a corroded metal.
One type of thickness gauge is an ultrasonic thickness gauge, also known as a UT gauge. These gauges use sound waves that are beyond the audible range of human ears to determine the thickness of an object in question. They do this by testing the amount of time it takes for the sound wave to return to the probe on the gauge. Ultrasonic thickness gauges can be used to measure the thickness of all sorts of metals and non-metals, including steel, aluminum, plastic and ceramic. Thickness detectors generally output the thickness of the object in inches or millimeters.
Ultrasonic thickness gauges must be calibrated to work properly. This is because sound travels through materials at different rates, depending on the hardness of the material. Generally, sound moves slower through harder materials and faster through softer ones. Before taking any measurement with a thickness gauge, it must be calibrated to read the appropriate material in order to achieve an accurate reading.
Other types of thickness gauges include coating thickness gauges and paint thickness gauges. These gauges are used to measure the thickness of whatever is coating a base material, often paint. One common use of a paint thickness gauge is for car dealers. At auctions, car dealers sometimes use a paint thickness gauge to measure the paint on a car to get a better sense of the quality of the paint job and its wear. They can also be used to measure coatings of other things like stain or laminate coverings.