H-4WEH25L6X/6EW110N9TDA/12B08

The H-4WEH25L6X/6EW110N9TDA/12B08 directional spool valve is produced by Bosch Rexroth for the WEH Directional Spool Valves series and is intended to switch high-pressure flow paths in automated hydraulic systems. It is built in nominal size NG25, a dimension that matches standard manifolds for medium-to-large actuators, and it follows the 4/3-way configuration so three stable positions can control extension, retraction, or block. The L spool symbol sets a center position that connects pressure to tank while blocking the work ports. Design designation 6X marks the internal construction stage, while a 4WE 6E pilot valve performs the remote actuation of the main spool. External port X feeds the pilot supply so control pressure can be maintained even when the main inlet is unloaded, and return flow from the pilot stage is routed internally to port T. The mounting face complies with ISO 4401-08-08-0-05, and a concealed manual override allows local shifting without exposing moving parts.

At full duty the valve passes up to 650 l/min when the inlet is held at 350 bar, enabling rapid cylinder or motor movement in high-flow installations. Continuous service pressure on the main P, A, and B ports is limited to 350 bar, while port T can withstand 250 bar so back-pressure can be used for counterbalancing functions. Reliable operation requires hydraulic oil with a viscosity between 2.8 and 500 mm²/s and a temperature from −20 °C to +80 °C, giving a broad envelope for both cold-start and elevated-heat work cycles. System cleanliness must stay within ISO 4406 class 20/18/15 to protect the precision-ground spool lands from abrasive wear. The assembled unit weighs 19.0 kg, a mass that reflects the cast housing sized for NG25 flow paths and hardened steel components. These parameters establish the valve as a robust pilot-operated element for applications needing fast response under demanding pressure and contamination conditions.