A precise and efficient coating thickness gauge is one of the most important quality assurance tools that a coating service provider should have in their arsenal. The coating thickness gauge helps the coating service provider to deliver high-quality coating that meets external standards and performs as intended.

Another reason why coating thickness gauges are important is that they help reduce material and labor costs by maintaining coating consistency. High-profile pieces of equipment in industries like the Military and Aerospace require proper coatings to perform efficiently.

When it comes to choosing the right coating thickness gauge, a lot of factors come into play like budget, basic application, and more. However, before all that you need to know what coating gauges are, how many types of coating gauges are there, and how they work.

What Is a Coating Thickness Gauge?

As mentioned earlier, there are some industries like aerospace and military that require precise and perfect coating on their equipment for effectiveness and efficiency. A coating thickness gauge is used to measure the thickness of material applied onto another surface like coating or paint.

Why not use a normal material thickness you ask? Sure, you can measure the thickness of the material before applying a coating then again after coating, and calculate the difference until you get the precise thickness of the coating. By using a coating thickness gauge, you’re taking the guesswork out of the game and simplifying the whole process.

There are numerous brands in the market like Coltraco Ultrasonics offering accurate and portable coating thickness gauges that will help you save time and cost. You can pick an ideal coating thickness gauge to serve your needs the best based on your usage cases.

Well-known brands like these offer thickness gauges that can be used in important sectors like maritime, fire safety, defense, manufacturing, transportation, and more. Each of these sectors requires a specific type of coating thickness gauge. Let’s proceed to the most popular type of coating thickness gauge equipment available.

Different Types of Coating Thickness Gauges

The coating thickness measurement is an elaborate process and having the right tools is an absolute must. In case you’re in the market for the perfect coating thickness gauge, you must know the types first. 

Ultrasonic Thickness Gauges

An ultrasonic thickness gauge makes use of an ultrasonic transducer to measure the coating thickness. A pulse of a sound wave is emitted into the coating and when it hits the metal boundary, it echoes back to the transducer. The ultrasonic thickness gauge then measures the time taken by the return pulse to be detected to measure the thickness of the coating or paint.

The ultrasonic thickness gauge works on nearly everything including composites, plastics, fiberglass, ceramics, and more. Ultrasonic thickness gauges are widely preferred because they are non-destructive, easy to use, and provide quick results. 

Dry Film Thickness Gauges

A dry film thickness gauge is used to measure the thickness of the dry film on a substrate. This type of toll is important in the coating industry as it helps in determining the quality, reliability, and longevity of the product or structure.

These gauges make use of magnets and calculate the force needed to pull a magnet away from the coated substrate as an estimate of coating thickness. There are three types – Type 1 magnetic pull-off gauges, Type-2 magnetic pull-off gauges, and roll-back magnetic pull-off gauges. All three types use different mechanisms to calculate the same pull-away force as an indicator of coating thickness.

Magnetic Induction Instruments and Electromagnetic Instruments

The magnetic induction instruments and electromagnetic instruments use magnetic flux density to measure coating thickness. As these gauges are brought near the coated surface, they measure the change in the magnetic flux density at the surface. The magnetic flux density value is then used to get an estimate of the thickness of the coating.

Eddy Current Thickness Gauge

Lastly, we have the Eddy Current thickness gauge. This type of gauges is used on non-conductive coatings applied on non-ferrous metal substrates. The Eddy Current thickness gauge generates a high-frequency alternating current to create an alternating magnetic field.

As this alternating magnetic field approaches the substrate, it creates eddy currents on the surface, which generate an opposing magnetic field. This opposing field is detected by the gauge to estimate the thickness of the coating. 

Now that you know what thickness gauge is, the different types of gauges, and how they work, we believe you’ll be able to pick the right tool for your requirement. With the right thickness gauge, not only will you save costs but also deliver quality service to your clients.

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