• Pressure and Flow Control Industries

Pilot Operated Pressure Relief Valves

Pilot Operated Relief Valves (PORV) are used for emergency relief during overpressure events (e.g. a tank gets too hot and the expanding fluid increases the pressure to dangerous levels). The distinction between PORV and conventional PRV is that pilot valves use system pressure to seal the valve. APRV typically uses a spring to hold the disc or piston on seat. The essential parts of a PORV are a pilot valve (or control pilot), a main valve, a pilot tube, the dome, a disc or piston, and a seat. The volume above the piston is called the dome.