Sealing of gases by lip type seal

[BasakAbhishek]

Hello,
Is it possible to have a reasonable level of leak tightness if a lip type seal (with grease lubrication) is used in a vertical shaft to seal against argon at 0.5 bar(g)?
Thanks!
Abhishek

 

[dtimberlake]

reasonable level of leak tightness ?
shaft size and rpm ?

 

[Compositepro]

The answer is yes. It is important to have a good finish on the shaft ( not too rough and not too smooth). It is also important to have adequate shaft support by bearings to prevent wobble or deflection at the seal.

 

[BEMPE16524]

actually lip seal is not really reliable for gas sealing but from what I read, PTFE rotary seals may be useful provided good surface finish of the shaft and you may need to add backup ring in the application.

 

[BasakAbhishek]

Hello ...thanks for the answers! If not a lip seal what other options do I have. My shaft is ~30mm dia, rotating at 2700 rpm.

 

[BEMPE16524]

Hello ...thanks for the answers! If not a lip seal what other options do I have. My shaft is ~30mm dia, rotating at 2700 rpm.

sorry, my bad, PTFE rotary seal is still a lip seal but not the normal rubber material.

 

[dgeesaman]

This is a question for the lip seal supplier. In my experience I'd say this is possible but not in all cases, and the effective life and/or leak rate may not meet your expectations. At one time a major lip seal supplier told us that their expectation for lip seal life before leak rates will increase is about 6 weeks. (!) Our expectation is years and I'm sure everyone else agrees.