How to reduce the leak detection rate of vacuum system
Principle of helium mass spectrometer leak detector:
The structure of vacuum system is the key to affect the sealing performance and air leakage rate of vacuum system. Whether the structure of vacuum system is reasonable or not will directly affect the sealing performance and air leakage rate of the system.
1. As far as possible to avoid the small curvature radius of the dead angle, to smooth transition check in the dust blowing polishing, cleaning and cleaning.
2. For the pipes connected with the vacuum chamber, such as the evacuation pipeline and the air supply pipeline, the arc transition is adopted to make the gas path unobstructed, but the convenience of cleaning and cleaning should be considered.
3. Carefully design the structure of various connectors in the vacuum chamber to make the air path smooth and avoid the gas path blockage.
4. When polishing the inner surface of vacuum system, the brighter the surface is, the less gas adsorption is, and the easier vacuum is obtained.
5. Reduce the volume of the vacuum chamber as much as possible and shorten the pipeline system.
Selection of sealing form:
The sealing form can be selected according to the required vacuum degree and the actual work needs.
After water cooling, the temperature of the sealing part is about 80 ℃, and the temperature of other parts can reach more than 100 ℃. Therefore, to choose a more ideal sealing ring material.
In addition to smooth surface, no scratch and crack, low permeability and outgassing rate, good heat resistance, oil resistance, and certain strength, hardness and elasticity are required for vacuum sealing rubber materials.