Rexroth Hydraulic Valve 4WRA6 Series Proportional Directional Valve with

Product Specification

4WRA6E30-2X/G24N9K4/V
4WRA6EA30-2X/G24N9Z4/V
4WRA6E15-2X/G24Z4/V
4WRA6E15-2X/G24K4/V
4WRA6E30-2X/G24K4/V Directional valve, Rexroth proportional hydraulic valve, made in Germany and imported

FAQ:

Frequently Asked Questions (FAQ) for Proportional Directional Valve Series 4WRA6

1. What is the 4WRA6 valve?

The 4WRA6 is a series of direct-operated proportional directional valves manufactured by REXROTH. It is designed as a subplate-mounted component and is typically used to control both the direction and flow rate of hydraulic fluid in a system, thereby managing the direction and speed of hydraulic actuators .

2. What are the main features of the 4WRA6 series?

• Direct-Operated Design: The valve spool is moved directly by proportional solenoids without the need for a pilot pressure stage .

• Spring-Centered Spool: When the solenoids are de-energized, the spool returns to and is maintained in the center position by compression springs .

• Mounting: Subplate mounting with porting interface according to ISO 4401 .

• Two Configurations: Available with external control electronics (4WRA type) or with integrated onboard electronics (OBE) (4WRAE type) .

• Flow Control: Provides proportional flow control with a progressive flow characteristic (metering notch) in addition to direction control .

3. What is the difference between 4WRA and 4WRAE?

The key difference lies in the location of the control electronics.

• 4WRA: Requires an external, separate amplifier to function. The amplifier processes the input signal (e.g., from a PLC) and provides the necessary power to the valve's solenoids .

• 4WRAE: Features Integrated OnBoard Electronics (OBE). The control electronics are built into the valve, allowing it to accept standard analog input signals (e.g., ±10 V or 4-20 mA) directly .

4. How do I read the model number? A typical 4WRA6 model code is structured as follows :

• 4WRA: Series designation for proportional directional valve without OBE. "E" after WRA (4WRAE) indicates integrated electronics.

• 6: Nominal size (06). Alternative size is 10.

• W / E / etc.: Spool symbol/type (e.g., W, E, EA), which defines the flow characteristics and center position condition .

• 07 / 15 / 30: Nominal flow rate in liters per minute at a pressure drop (Δp) of 10 bar. For size 06, common values are 7, 15, or 26/30 L/min .

• 2X: Component series (20-29).

• G24: Supply voltage (24 V DC).

• K4 / K31: Electrical connection type (e.g., without plug, with specific component socket) .

• V: Seal material (e.g., FKM for mineral oil) .

• A1 / F1 (for 4WRAE): Control value input type (A1 for ±10V, F1 for 4-20mA) .

5. What are the key technical specifications?

• Maximum Operating Pressure: Up to 350 bar for P, A, B ports .

• Maximum Flow: Varies with model (e.g., 42 L/min for some 4WRAE6 models) .

• Recommended Fluid Cleanliness: ISO 4406 20/18/15 .

• Voltage: Typically 24 V DC .

6. What are common applications for the 4WRA6 valve?

These valves are used in various industrial hydraulic systems requiring precise control, such as:

• Plastic injection molding machines .

• Presses and bending machines .

• Mobile equipment.

• Industrial automation systems where proportional control of speed and direction is needed.

7. What are common troubleshooting issues?

Common problems and their potential causes include :

• Valve does not shift or responds slowly: Check solenoid coil for burnout or open circuit; check power supply voltage; check for contamination causing the spool to stick.

• Internal Leakage: Worn spool or seals, or contamination causing improper sealing .

• Valve sticking: Often due to inadequate fluid cleanliness, insufficient lubrication, or internal damage .

• Excessive noise: Can be caused by excessive vibration, voltage fluctuations, or issues with the solenoid .

• No function despite signal: Check the amplifier (for 4WRA), wiring, and connections between the control unit and the valve .