Fisher Type 289P pilot-operated relief valve is used to provide over pressure protection for downstream systems suitable for service on natural gas, air, propane, or any other operating medium not corrosive to the internal parts. Smooth opening action minimizes system pressure surges during emergency action. Very little buildup over set pressure is required to completely open the main valve for max relief capacity. The external control line provides quick, accurate pressure registration.
Specifications
Body Sizes and End Connection Styles
1 or 2 NPT
Maximum Relief (Inlet) Pressure
1 NPT: 50 psig / 3.4 bar over relief set pressure or 110 psig / 7.6 bar whichever is lower
2 NPT: 15 psig / 1.0 bar
Relief Set Pressure Range
1 NPT: 10 to 100 psig / 0.69 to 7.0 bar in three ranges
2 NPT: 14-inches w.c. to 10 psig / 35 mbar to 0.69 bar in two ranges
Pressure Registration
External
Temperature Capabilities
With Nitrile (NBR): -20 to 180°F / -29 to 82℃
With Fluorocarbon (FKM): 0 to 300°F / -18 to 149℃
Features
Economical
High Relief Capacity with Low Buildup
Accurate
Fast Reseat After Operation
Ease of Maintenance
Rugged Construction
Corrosion Resistant Fasteners
Full Usable Capacity
