Reasons for rotary evaporator cannot reach vacuum

Rotary evaporator is a commonly used evaporation instrument in laboratories, and is widely used in chemical industry, biomedicine and other industries. Then how to deal with  a situation where the vacuum cannot be pumped?

Possible reasons why lab rotary evaporator cannot reach vacuum or cannot pump vacuum:

1. The joints and interfaces of each component of the rotary evaporator are not properly sealed.

2. The sealing ring does not seal well or the sealing ring fails.

3. Vacuum grease is not applied between the rotary evaporation spindle and the sealing ring or the vacuum grease is not applied properly.

4. The vacuum pump for vacuuming is damaged, and the hose connecting the vacuum pump and the rotary evaporator is leaky and damaged.

5. Check whether the glass parts of rotary evaporator are cracked, broken or damaged.

6. The connecting pipelines are aging and leaking.

Another method is to replace and disassemble all items of vacuum rotary evaporator at once, and tAnd after each connection, test by blocking the open upstream connector by plugging or other means, so as to find the item with problems step by step.