Methods for Modifying the Coating Thickness Gauge's Parameters Head Measuring
Coating thickness gauge has become an important process of finished product quality inspection in many industries, and it is a necessary means for products to meet high-quality standards. The suction force between the permanent magnet (probe) and the magnetic steel is proportional to the distance between the two, and this distance is the thickness of the cladding. Using this principle to make a thickness gauge, as long as the difference between the magnetic permeability of the coating and the base material is large enough, it can be measured. Since most industrial products are stamped and formed by structural steel and hot-rolled cold-rolled steel plate, they are widely used.
The basic structure of coating thickness gauge is composed of magnetic steel, relay spring, scale and self-stop mechanism. After the magnetic steel is attracted to the measured object, the measuring spring is gradually elongated thereafter, 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 the magnetic steel is detached. The new product can automatically complete this recording process. This instrument is characterized by easy operation, durability, no power supply, no calibration before measurement, and low price, which is very suitable for on-site quality control in workshops.
Coating thickness gauge is an effective means of non-destructive measurement of non-conductive coating thickness on 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 requires the help of oxidation Anti-corrosion protection of film, paint, plastic spraying, rubber and other surface coverings to prolong their service life.
When the measuring head of the coating thickness gauge is in contact with the tested sample, the high-frequency electromagnetic field generated by the measuring head device will cause the metal conductor placed under the measuring head to generate eddy current, and its amplitude and phase are the non-conductive between the conductor and the measuring head. 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 layer. By measuring the size of the probe parameter variable 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 used to calibrate the instrument should be used. This is accomplished by zeroing the instrument on an uncoated test piece on which the coating thickness measurement will be made.
