4WRZ25E2-325-7X/6EG24N9K4/D3M-674

The 4WRZ25E2-325-7X/6EG24N9K4/D3M-674 valve is produced by Bosch Rexroth as part of the WRZ Proportional Directional Valves series. It regulates flow and direction in automated hydraulic circuits by shifting a main spool under electro-hydraulic control. A nominal flow of 325 l/min at a differential pressure of 10 bar allows the designer to size actuators for medium to high flow requirements, while a maximum operating pressure of 350 bar makes the unit compatible with high-pressure systems found in presses or die-casting machines. The solenoid is energized with a 24 V DC coil, enabling direct connection to common machine control voltage. A DIN EN 175301-803 plug provides a standardized electrical interface and simplifies field service. Subplate mounting speeds installation because the body is clamped to a manifold without pipe joints, and the ISO 4401-08-07-0-94 porting pattern ensures interchangeability with other valves on the same interface. Hysteresis does not exceed 6 percent, so commanded spool positions are reproduced with limited deviation, and a concealed manual override lets maintenance staff shift the spool without removing protective covers when electrical power is absent.

The valve can pass up to 870 l/min through the main stage during peak demand, which prevents pressure loss during rapid cylinder movement. Port Y is limited to 30 bar to protect the external pilot drain path, whereas the return port T can withstand up to 250 bar so back pressure in the tank line does not compromise spool centering. Pilot oil is supplied internally to avoid an additional feed line, and the drain is routed externally through port Y to keep pilot pressure stable regardless of tank fluctuations. A step input requires only 7 l/min of pilot oil, promoting fast response without oversizing the pilot circuit. The hydraulic fluid must be filtered to ISO 4406 class 20/18/15 or cleaner to maintain spool clearances and proportional accuracy. A subplate weight of 18.2 kg should be considered when selecting handling equipment during assembly.