In the air tightness test, no matter what kind of device is used, the air tightness of the detection device should be first used to ensure that the test can be carried out smoothly.
The multi-stage plunger pump is usually used to detect the air tightness of valve ball valves. According to the principle of pushing high pressure and small area in a large area at low pressure, the plunger in the pump can move to and fro to produce high pressure continuously and then output. Pressure will continue to increase, making the pump slower and slower, until the force balance between each other, and finally make the pump stop operating.
If the multi-stage plunger pump can stop smoothly, it shows that the pressure in the valve ball valve has reached balance and no excess gas leaks out, then the air tightness of the valve ball valve can be regarded as meeting the requirements.