Pressure Relief valves are used to limit the pressure in the system as set on the valve. Pilot Operated Relief Valves are applicable more in systems where pressure regulation is needed over pressure safety. The barrel-piston assembly of the valve implies that the valve is not a zero leak valve and cannot be used for load holding applications. The valve is ideal for continuous duty providing accurate pressure control with constant or varying flows.
When the inlet pressure at 1 (Pressure Port) exceeds the setting of the valve, the ball unseats causing the pilot section to open. This results in a small flow across the orifice in the main spool. The subsequent pressure drop moves the secondary spool against a light spring opening a ring of radial holes in the sleeve and allowing relief flow to 2 (Tank Port)
Very low pressure rise for any increase in flow giving accurate pressure control. Smooth operation due to presence of a balanced piston. Hardened working parts ensure a long, reliable, trouble-free life. Cartridge construction gives maximum flexibility in mounting