Colección:Hydraulic Inline Pressure Relief Valves

Hydraulic inline pressure relief valves limit the system pressure by relieving excess oil from P to T. They mount directly in the pipe line with threaded ports, for overpressure protection of a pump and its circuit, or for continuous pressure control. Every hydraulic system with a fixed displacement pump needs a relief valve, because the pump keeps delivering flow when the actuators stop.

Two designs are common. Direct-operated valves open against a spring and respond very quickly, which makes them suitable for smaller flows and for absorbing pressure peaks. Pilot-operated valves use a small pilot stage to control a main stage, which keeps the pressure more stable over a wide flow range and suits larger flows.

Choose the valve on three values. First the setting range: pick the range that contains the required pressure. Second the nominal flow, which must cover the full pump flow. Third the port thread. Note that the lowest setting of a relief valve rises with flow, so a valve set near the bottom of its range may not reach the required low pressure at full flow.