Pilot PSV Popping far below set pressure
Pilot PSV Popping far below set pressure
(OP)
Anyone have experience with Pilot PSVs popping significantly below set pressure? I have some in ethylene service that keep popping and not in the other systems. There appears to be some issue with Ethylene and the pilot mechanism. Any ideas on what could be the failure mechanism or how to investigate this would be appreciated.





RE: Pilot PSV Popping far below set pressure
It might the pilot valve being stuck open due to very low temperature conditions; hence the process pressure cannot be kept above the main valve to keep it closed even in low and normal pressure inside the relevant vessel/tank...
RE: Pilot PSV Popping far below set pressure
Per ISO, only the term Safety Valve is used regardless of application or design.
RE: Pilot PSV Popping far below set pressure
RE: Pilot PSV Popping far below set pressure
I am sure you can find a commercial available PSV system with pilot fluid separated from the process fluid. This could perhaps help avoiding unwanted release. Although a high-cost solution this could be economic positive in the long run avoiding extra costs at shut-downs and maintenance.
Example: http://www-eng.lbl.gov/~shuman/NEXT/MATERIALS&...
RE: Pilot PSV Popping far below set pressure