Pilot operated PSV

[kmg1983]

Hey guys...For Crude oil application, we have a pilot operated pressure relief valve, set pressure of 235 psi, which has recently been "leaking by" with only 14-15 psi on the line. What are possible causes of this? There is a filter screen installed in the pilot sense line which may be plugged or clogged with debris, this is my thought...any other thoughts as to what may be causing this? The main valve has been sent in for service and cleaning once before after a similar issue. Also, can someone explain the concept behind the proper operatin of a Pilot Operated Safety Relief Valve (differential pressure, etc)? Thanks in advance.

 

[Ashereng]

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You already have 3 answers to this question in your other post.

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