What non-contact thickness gauges are there?

Non-contact thickness gauges include X-ray thickness gauges, Y-ray thickness gauges (mainly saw and blunt), ultrasonic, infrared and laser thickness gauges. The first two types are radiation thickness gauges, which are made according to the principle that the attenuation intensity of rays has a certain relationship with the thickness of steel plates when they pass through steel plates with certain energy.

After the radiation source emits radiation, a part of it is generally absorbed by the steel plate from bottom to top, and the rest is accepted by the detector. When there is no steel plate in the measuring space, a reference plate with known thickness is used for calibration.

Main types:

An instrument used to measure the thickness of the material itself or the thickness of the coating on the surface of the material. The thickness of some parts must be measured during manufacturing and maintenance to understand the thickness specification, uniformity of each point and corrosion and wear degree of the material; Sometimes it is necessary to measure the thickness of the surface coating of materials to ensure product quality and production safety. According to the different measuring principles, there are four commonly used thickness gauges: ultrasonic thickness gauge, magnetic thickness gauge, eddy current thickness gauge and isotope thickness gauge.

Ultrasonic thickness gauge The sound speed of ultrasonic wave in various media is different, but in the same media, the sound speed is constant. Ultrasonic waves propagate in one medium and will be reflected when they meet a second medium. By measuring the time interval between the transmission and reception of ultrasonic pulses, time can be converted into thickness. This kind of thickness gauge is widely used in electric power industry.

It is often used to measure the thickness of boiler drum, heating surface pipe and pipeline. , and check the structural dimensions of the workpiece. This kind of thickness gauge is mostly portable, its volume is similar to that of a small transistor radio, and its thickness value display is mostly digital. For steel, the maximum thickness is about 2000 mm, and the accuracy is between 0.01~ 0.1mm.

When measuring the magnetoresistance of various magnetic materials with a magnetic thickness gauge, the measured values will change because of the different thickness of the non-magnetic coating on their surfaces. This change can be used to measure the thickness of the coating. It is often used to measure the thickness of sprayed aluminum layer, plastic layer, electroplating layer, phosphating layer and paint layer on ferromagnetic metal surface.