Tips for changing coating thickness gauge probe parameters
Coating thickness gauge has become an important process for finished product quality testing in many industries and is an essential means for products to meet high quality standards. The attraction force between the permanent magnet (probe) and the magnetically permeable steel is proportional to the distance between the two. This distance is the thickness of the coating. This principle is used to make a thickness gauge, which can be measured as long as the difference in magnetic permeability between the coating and the base material is large enough. Since most industrial products are stamped from structural steel and hot-rolled and cold-rolled steel plates, they are widely used.
The basic structure of the coating thickness gauge consists of magnetic steel, relay spring, scale and self-stop mechanism. After the magnetic steel is attracted to the object to be measured, the measuring spring is gradually stretched and the pulling force is gradually increased. When the pulling force is just greater than the suction force, the thickness of the coating can be obtained by recording the pulling force at the moment when the magnet is detached. The new product can automatically complete this recording process. This instrument is characterized by easy operation, durability, no need for power supply, no need for calibration before measurement, and low price, making it very suitable for on-site quality control in workshops.
The coating thickness gauge is an effective means of non-destructively measuring the thickness of the non-conductive coating on the non-magnetic metal substrates listed above. The development and application practice of modern engineering materials shows that the wide application of aluminum, copper, zinc and other non-ferrous metal materials and their alloy materials in aviation, building materials, metallurgy, light industry, machinery, instrumentation, chemical industry and other industries often require the help of oxidation Anti-corrosion protection of surface coverings such as films, paints, plastic sprays, and rubber to extend their service life.
When the coating thickness gauge probe comes into contact with the test sample, the high-frequency electromagnetic field generated by the probe device causes the metal conductor placed under the probe to generate eddy currents. The amplitude and phase are the non-conductive between the conductor and the probe. A function of the coating thickness, that is, the alternating electromagnetic field generated by the thickness gauge will change the probe parameters, and the size of the probe parameter variables depends on the thickness of the coating. By measuring the size of the probe parameter variables and converting this electrical signal, the thickness value of the measured coating can be obtained.
Once the coating thickness gauge is calibrated, the parameters are saved and the calibration process does not need to be repeated. It is recommended that after prolonged operation or when the instrument has not been used for a period of time, the same calibration matrix/foil as the instrument was previously calibrated should be used. This process is achieved by zeroing the instrument on an uncoated test piece, and the coating thickness will be measured on this test piece.
