4WEH22J7X/6EW110N9S2DK25L

The 4WEH22J7X/6EW110N9S2DK25L directional spool valve belongs to the WEH Directional Spool Valves series from Bosch Rexroth and provides hydraulic actuation by switching flow paths in automated circuits. Its 4-way configuration creates separate pressure and return channels to accommodate common cylinder or motor circuits. The valve body is built to NG25 size so it mates with manifolds designed for this mounting footprint. An ISO 4401 porting pattern aligns the pressure, work, and tank ports with standardized subplates, simplifying replacement. The flow galleries permit up to 450 l/min, allowing high-volume systems to operate without excessive pressure loss. Hydraulic media should have a viscosity between 2.8 and 500 mm²/s to keep internal clearances lubricated while maintaining response speed. Contamination must not exceed ISO 4406 class 20/18/15 so that the spool lands remain free from abrasive wear. Working ports P, A, and B withstand 280 bar, while port T tolerates 250 bar to protect the return line against over-pressure during dynamic events.

The pilot stage can receive up to 210 bar, giving ample force to shift the main spool under full flow conditions without risking damage to the control cover. For spring-centered operation, a minimum pilot pressure of 10.5 bar is required so the spool moves reliably to each detented position and returns to center when the signal is removed. Service temperatures range from −20 °C to +50 °C ambient and −20 °C to +80 °C for the hydraulic fluid, enabling outdoor installations across moderate climates and ensuring seal materials stay within their rated limits. Two M12 × 60 screws according to ISO 4762 secure the valve to the subplate, and each fastener must be tightened to 100 Nm to maintain sealing integrity under pressure peaks. With both solenoids fitted and the spring-centered design, the assembly weighs 11.9 kg, making manual handling feasible during machine maintenance without lifting equipment. An MTTFd of 100 years indicates a very low probability of dangerous failure throughout typical equipment life cycles, supporting compliance with performance level calculations in safety-related control systems.