Improving the sealing performance of vacuum system of vacuum pump
How to improve the vacuum system sealing of vacuum pump unit, the first is to strengthen the correction of vacuum system leakage, the formation of poor vacuum sealing elements generally adopt four measures.
1. During the overhaul, the gap of the vacuum pump shaft seal was adjusted to 0.35-0.45mm by rolling adhesive tape. During the operation of the vacuum pump unit, the steam pressure of the shaft seal was improved as much as possible on the premise of no water in the lubricating oil.
2. Improve the structure of low-pressure explosion-proof door. After the transformation, the inner side of the flange is sealed with reinforced graphite gasket, the outer side is sealed with asbestos paperboard gasket, and the inner flange is sealed with high and low steps. During the overhaul, the 2mm thick high-pressure paperboard diaphragm was replaced. During the assembly, hz-1213 oil resistant silicone sealant was applied on each joint surface to ensure the tightness of each joint surface.
3. For the vacuum system below the condenser throat, the method of filling water to check the leakage is selected to eliminate the leakage point.
4. In view of the large void value at the low-pressure steam inlet and the connection part between the middle section of the low-pressure cylinder and the low-pressure cylinder, the low-pressure upper cylinder and the middle section of the low-pressure cylinder are recombined. In the combination process, the sealing coating for the straight contact surface is replaced. The red lead powder is 20% ～ 25%, the fineness is 200%, the iron powder is 25% ～ 30%, and the fine black lead powder is 50%. According to the component ratio, the TR3 type cylinder sealing grease produced by Westinghouse is prepared. The coating is also used for the middle section of the low pressure cylinder. For the horizontal bisector of the middle section of the low pressure cylinder and the contact part of the low pressure cylinder, the coating with the thickness of 0.50 ～ 1.0 mm is applied first And then the sealing method of sealing glue is added on the coating layer; the exhaust hood is sealed with sealant.