4 replies to this topic

[Akumar]

Hi,

 

Could any one explain me about the criteria to install two PSV in series?

 

Best Regards,

Anil

[fallah]

Anil,

 

If you mean combination of RD/PSV, it's applicable for dirt, corrosive or high viscous fluid to prevent the PSV as main pressure relief device to be subject to such fluids before RD rupture....

Edited by fallah, 26 May 2014 - 05:50 AM.

[Akumar]

Dear Fallah,

 

Thank you very much for the reply.

 

We have a instrument air cylinders available at 200 barg and to the distribution header i designed PCV (set @ 8.5 barg) and two PSV (set @ 10 barg) downstream PCV. Now at the time of HAZOP, some recommendations are to keep 2 PSV upstream to PCV. I found no purpose of PSV upstream PCV but interested to know if there is any criteria.

 

Best Regards,

Anil

[fallah]

Anil,

 

Has the air cylinders their own PSVs?

 

Please upload a simple sketch of the system for more clarification...

Edited by fallah, 26 May 2014 - 11:31 AM.

[Bobby Strain]

And the system you described is not 2 PSVs in series.

 

Bobby