Vacuum coating equipment leak detection method

- Oct 16, 2018-

Vacuum coating equipment leak detection is so important, can you do leak detecting?


The leakage detection of vacuum coating equipment is an inspection measure to ensure the vacuum degree of vacuum coating equipment, referred to as the leakage detection. The vacuum degree directly affects the coating effect, so the leakage detection is essential.


Generally, air leakage in vacuum chamber is generated from some small holes on the wall of the chamber or the connection joints in front of the components. After the system is pumped down, the pressure in the vacuum chamber was decrease. The pressure difference between the external and the internal, causes the gas to flow from the external with high pressure to the vacuum chamber with low pressure, resulting in vacuum degree decreased.


The vacuum coating equipment needs to pay attention to the following problems in the process of leak detection, in order to do a good job of leak detection.

1. To confirm the leakage whether virtual leakage or real leakage. Because the work piece material will produce gas in different degrees after heating, it is possible to mistakenly think that the gas flows come in from the outside, which is the virtual leakage, to eliminate this situation.

2. Test the gas seal performance of vacuum chamber. Ensure airtight performance to meet requirements.

3. Check the size, shape, position, and velocity of the leakage hole, to prepare a solution and implement it.

4. Identify the minimum leakage rate and sensitivity of the testing instrument, to detect the leakage situation to the maximum extent, avoid some leakage holes to be ignored, and improve the accuracy of leakage detection.

5. Control the response time and elimination time of the leak detector. Control the time well, make sure that the leak detector works well, the time is short, the leak detection effect is definitely poor, the time is long, the gas of leak detection and the labor electricity fee are wasted.

6. Avoid leaky holes blocking. Sometimes due to the operation error, during the leak detection process, some dust or liquid, etc. plug the leak hole, thinking that there is no leak hole at this position, but when these plug due to the difference in internal and external pressure or other reasons that the leak hole is not blocked, that leakage exists.


It is very important to do a good job of leakage detection for vacuum coating equipment. There are various reasons for vacuum degree reduction, and we need to solve these reasons one by one to stabilize the effect of coating.