Rexroth Hydraulic Proportional Directional Valve with ISO 4401 Mounting 315 Bar Maximum Pressure and 75 L/min Flow Rate

The REXROTH 4WRA6 is a direct-operated, proportional directional valve without electrical position feedback or integrated electronics (OBE). It controls the direction and volume of hydraulic fluid flow and is designed for subplate mounting per ISO 4401 standards. Its maximum operating pressure is 315 bar, with flow rates up to 75 L/min (depending on model).

• Direct-operated design for precise flow control without external feedback
• Proportional solenoid control with detachable coils and centering thread for easy maintenance
• Spring-centered spool that returns to neutral when de-energized
• Compatibility with external electronics (e.g., Eurocard amplifiers) for signal control
• Compact sizes: NG6 and NG10

When an electrical signal is sent to the proportional solenoid, it generates a force that moves the spool proportionally. This adjusts the opening of flow paths between ports P (pressure), A/B (actuator lines), and T (tank), enabling continuous control of flow direction and volume. The spool returns to center via springs when de-energized.

This valve suits applications requiring precise hydraulic control, such as:

• Industrial machinery (e.g., presses, plastic injection molding)
• Mobile equipment (e.g., cranes, excavators)
• Systems needing directional and flow control without integrated electronics

Model codes indicate specifications (e.g., 4WRA6E07-2X/G24N9K4/V):

• 4WRA6: Series and size (NG6)
• E07: Spool type and control configuration
• G24N9K4: 24V DC supply, corrosion-resistant coating

Consult REXROTH datasheets or suppliers for exact requirements like flow rate, spool type, and electrical inputs.

• Use the specified subplate (ISO 4401) to avoid leakage
• Ensure the tank line is never unloaded; a pre-load valve (~2 bar) may be required
• Verify electrical connections (e.g., 24V DC) and coil compatibility

• Regularly check for spool sticking or contamination
• Clean filters and monitor hydraulic fluid quality
• Replace coils or seals if movement is sluggish

• Check power supply to the solenoid
• Inspect for debris blocking the spool
• Verify external amplifier signals (if used)

If issues persist, contact technical support.

Yes, certain models are designed for explosive atmospheres (e.g., corrosion-resistant, certified coils). Confirm model suffixes like "K4" for environmental suitability.

REXROTH distributors or official service centers provide documentation, troubleshooting, and spare parts. Include the full model code when seeking help.