How to use the coating thickness gauge on plastic products
Measurement of coatings on plastic products. When using the ultrasonic method for measurement, it is common for the coating to dissolve with the substrate, resulting in a lack of a good acoustic reflection surface, which can lead to measurement failure or serious deviation in readings. If the cutting wedge method is used for measurement, there are also many places where it is inconvenient to use and difficult to read. Humidity sensor probe, stainless steel electric heating tube PT100 sensor, cast aluminum heater, heating coil fluid solenoid valve
Therefore, currently portable electronic product manufacturers commonly use the transfer method to measure the coating on plastic products.
We have developed a method for coating thickness gauges through years of practice, which involves first covering the product with several small strips of standard thickness polyester film, and then pressing the two ends with paper-based masking tape to leave the middle part. Place the product on the spraying line for normal spraying and baking.
After the product is completed, remove the polyester film with the remaining paint film, use an iron (or aluminum) plate as the substrate, and use a magnetic induction (or eddy current method) film thickness gauge to measure the coated and uncoated parts respectively. The difference between the two is the coating thickness. Due to the use of the same zero plate, the electromagnetic induction reference point will not change, ensuring that the measurement reference remains unchanged and the accuracy of the measurement is guaranteed. In addition, especially due to the use of differential method, the errors of the instrument and zero plate will be offset by subtraction. This greatly reduces the requirements for zero plate and instrument accuracy.
Some factories still use the method of pasting iron and aluminum sheets. It should be noted that the different surface roughness, convex and concave deformation, and thickness changes of each iron or aluminum sheet may cause changes in the electromagnetic induction reference point, which may increase measurement errors and result in poor repeatability. Attention should be paid to avoiding.
