Technical Parameters Category Parameter Specification / Description General Model 249B Type Pilot-Operated Backpressure Relief Regulator Pressure & Capacity Body Pressure Rating (ANSI) ANSI Class 150, 300, 600 Max. Inlet Pressure (P1) Up to 1440 psig (99 bar) for Class 600 bodies. Setpoint Pressure Range Wide range, adjustable via the pilot spring. Common ranges from 30 to 1200 psig (2 to 83 bar). Flow Capacity (Cv) Very High. Ranges from ~50 to over 2000+, depending on the main valve size (e.g., 1", 2", 3", 4", 6", 8"). Construction & Materials Body Materials Carbon Steel (Standard), Stainless Steel, Other Alloys. Trim Materials Stainless Steel. Main Valve Seat Metal-to-metal for durability, or soft seat for tighter shut-off. Pilot Valve 249B Pilot (Relief Pilot) - senses upstream pressure. Connections & Environment Inlet/Outlet Connections Flanged (RF, RTJ) per ANSI standards. Vent Connection Flanged or threaded. Ambient Temperature Standard: -20°F to 150°F (-29°C to 66°C).
