Reverse rotation of centrifugal compressor

[curious cat]

Referring to

https://www.academia.edu/27687837/T...rectional_groove_dry_gas_seals_with_slip_flow

I would like to survey field operating experience , if the reverse flow of compressors phenomenon during shutdown is a fact or a myth conjured by OEM to market specialty products at premium cost.

 

[LittleInch]

Care to explain this a bit more?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[JJPellin]

I have experienced only one event that I can recall where a centrifugal compressor spun in reverse. My experience includes about 40 major compressor trains and more than 30 years. It is rare, but it does occur. For some positive displacement machines, it is common. We have one dry screw compressor that spins backwards almost every time it shuts down.

Johnny Pellin

 

[Gholam Baghery]

Hi
Check the check valves. The outlet of the compressor has more pressure than the inlet, so, when you turn the compressor off, the flow gets back and rotates the shaft in the reverse direction. It doesn't make any problem for the compressor, but it shows an inner leakage through the check valves.

 

[OpticControl]

Gholam Baghery's comment is correct.

I usually see check valves installed on the discharge of the compressor. This should prevent reverse rotation of the compressor.

Although this is unlikely, it is considered in safety protection scenarios.

Regards.