Patent ID: 7219688

Claim:
A seal support system, comprising: a vessel for holding barrier fluid, said vessel having an inlet for a supply of said barrier fluid to said vessel from a barrier fluid source; means for feeding said barrier fluid between said vessel and a mechanical seal; and, a fluid control valve for fluid connection between said barrier fluid source and said inlet for said supply of said barrier fluid, and for controlling said supply of barrier fluid to said vessel via said inlet, said fluid control valve including: a housing having a fluid inlet and a fluid outlet defining a flowpath therebetween, said housing having a chamber located in said flowpath between said fluid inlet and said fluid outlet; a valve mounted within said chamber for movement being an open position allowing for fluid along said flowpath and a closed position for preventing said flow; means for biassing said valve toward said open position; means for regulating fluid pressure for enabling the fluid pressure to be set on an inlet side of said valve; and, means for biassing said valve toward said closed position, said means for biassing said valve toward said open position and said means for biassing said valve toward said closed position being balanced when said valve is in said open position.