How to dehumidify the vacuum coating machine?

Vacuum is the environment that supports the operation of vacuum coating machines, especially equipment that requires high vacuum. Usually, we need to achieve a high degree of vacuum, and the function of the pumping system is indispensable. However, in addition to the exhaust system, there is another point in the operation of the vacuum coating equipment, which is the degassing of the workpiece.

Some workpieces have a lot of gas and moisture inside, which will be discharged into the vacuum chamber when the equipment is heated, reducing the vacuum degree. What's more, some gases contain toxic components, which directly damage the internal mechanical structure of the vacuum chamber, causing the equipment to fail to operate normally. Steel plate coating machine.jpg

In addition, during the coating process, due to the thermal expansion of the gas in the workpiece, it is easy to crack the coated film. Of course, the probability of this situation depends on the physical properties of the workpiece itself. For example, for materials that are easy to expand, such as plastic, the probability is relatively high, while for hard materials, such as metal, the probability is relatively low, but it cannot be ignored. Therefore, the degassing of the workpiece is very necessary.

The commonly used degassing method for workpieces is baking. The gas and moisture in the workpiece are discharged by heating. Before painting, the workpiece is heated while pumping. When the moisture and gas in the workpiece are released due to heat, they are pumped out together with the gas in the vacuum chamber by the vacuum pump.

Taking different degassing measures for different workpieces can effectively control the discharge of gas and water inside the workpiece and improve the stability and uniformity of the coating.