Emerson Sempell PSRV VS99

18
SEMPELL MODEL PSRV - PRESSURIZER SAFETY RELIEF VALVES
TYPE VS99 PILOT OPERATED
The pressure transfers its opening force
through the impact plate to the check disc 2 of
the pilot part. Because the opening forces of
the impact plate, as conditioned by the large
surface, exceeds the closing forces of check
disc 2, the check disc opens and immediately
initiates pressure relief of pilot line C for the
main valve.
The main valve opens and remains open as
long as the pilot valve is open.
FUNCTION VS66
System pressure through opening pressure
Disc 1 Open
Disc 2 Open
Chamber A System pressure
Chamber B Pressure increase
Chamber C Pressure relief
System pressure through opening pressure
Disc 1 Open
Disc 2 Open
Chamber A System pressure
Chamber B Pressure filled
Chamber C Pressure relief