4WS2EM10-5X/20B11ET315K8DV

The 4WS2EM10-5X/20B11ET315K8DV servo valve is produced by Bosch Rexroth and belongs to the 4WS Servo Valves series. It meters hydraulic flow to position cylinders or motors in closed-loop automation systems. The valve is built in size 10, which defines the port mounting pattern and overall flow capacity. With a rated flow of 20 l/min at a 70 bar differential, it can drive medium-sized actuators without exceeding pressure losses. A negative spool overlap designated E minimizes deadband so the control loop responds quickly around the null position. The electromagnet requires a coil current of 30 mA and presents a coil resistance of 85 Ω, allowing standard servo amplifiers to command the spool. Internal pilot oil supply and return, coded ET, eliminates the need for external pilot lines and simplifies manifold design. Continuous service up to 315 bar operating pressure lets the valve work in high-pressure circuits common in industrial presses and injection machines.

The unit can be installed in environments from −30 °C to +100 °C when the on-board electronics are not fitted, accommodating outdoor or high-temperature machinery. Hydraulic fluid may reach +80 °C, so the valve housing and seals are rated to maintain clearance and leakage control at elevated oil temperatures. FKM seals resist mineral oils and many synthetic fluids, reducing maintenance caused by elastomer degradation. A mechanical return system recenters the spool without relying on electronic feedback, providing a fail-safe neutral position during power loss. Ingress protection to IP65 prevents dust and low-pressure water jets from affecting the armature and connector, which supports reliable field operation. These characteristics, combined with the internal pilot scheme described earlier, allow the valve to maintain precise position control across a wide thermal and environmental range.