How to use the coating thickness gauge and matters needing attention
Coating Thickness Gauge for non-destructive measurement of non-conductive coatings (e.g. enamel, enamel, tin, etc.) thickness of rubber, paint, plastic, etc.).
The coating thickness gauge has the characteristics of small measurement error, high reliability, good stability and convenient operation. It is a testing instrument for controlling and guaranteeing product quality assurance. Widely used in manufacturing, metal processing, chemical industry, commodity inspection and other testing fields.
1. How to use the coating thickness gauge
After the battery is installed on the instrument, press the "ON/OFF" button to start the machine, and the calibration table will return to zero. When the LCD displays "0", the instrument will automatically enter the measurement state, and directly press the probe vertically to quickly reach the coating on the surface of the workpiece. The instrument automatically passes through the probe. Measure the thickness of the coating, and display the thickness value through the display (Note: keep the probe vertical when measuring)
2. Precautions for the operation of the coating thickness gauge
Coating Thickness Gauge is a non-destructive testing instrument specially used to measure the thickness of various paint films. Many people find that the measured data has a large error when measuring. Why does this happen?
In fact, even with the same coating thickness gauge, the data measured by different people or the same coating on different types and conditions of substrates can vary widely. It is caused by the film's substrate material, thickness, surface condition and measurement location. When using a coating thickness gauge, pay attention to the following points when using a coating thickness gauge:
(1) Please read the instrument manual carefully before use
Instruments of different manufacturers and brands are different in terms of structure, keys, calibration, etc., so be sure to read the instruction manual of the instrument carefully before use, so as to avoid errors in measurement data caused by misoperation.
(2) Pay attention to the metal substrate
The magnetic properties and electrical conductivity of different metal substrates are different, which will affect the measurement results. Magnetic thickness measurement is affected by changes in the magnetic properties of the base metal (in practical applications, the changes in the magnetic properties of low carbon steels can be considered slight). Standard sheets are used to calibrate the instrument, and test sheets to be coated can also be used for calibration. Due to the difference in the composition and heat treatment method of the base metal, its electrical conductivity is also different, so the standard sheet with the same properties as the base metal of the test piece should be used to calibrate the instrument.
(3) Pay attention to the shape of the test piece
In actual production, there are differences in the material thickness, shape and surface roughness of the workpiece, and these differences will affect the actual measurement results. Each instrument has a critical thickness of jian metal. Above this thickness, the measurement will not be affected by the thickness of the base metal. If the thickness of the specimen material is less than the critical thickness required by the instrument, the test result will be different from the actual thickness. Some instruments are very sensitive to the sudden change of the surface shape of the sample, so the value measured near the edge or inner corner of the sample will be unreliable, and the actual measurement should be selected away from the edge and inner corner. The surface of the specimen not only has abrupt changes in shape, but may also have different curvatures. Measurements from some instruments always increase significantly as the radius of curvature decreases. Therefore, even if the minimum radius of curvature is considered in the selection of the instrument, measurements should be made on as flat an area as possible.
