Product Overview

The 4WREE10 is a Bosch Rexroth proportional directional valve designed for continuous hydraulic flow-direction and flow-volume control.

The 4WREE family is a direct-operated proportional directional valve with electrical position feedback and integrated valve electronics (OBE). Rexroth specifies this series for subplate mounting and standard interfaces including DIN 24 340 Form A, ISO 4401 and CETOP-RP 121 H.

The two configurations relevant to your original title are:

• 4WREE 10 E1-50-2X/G24K31/A1V
• Rexroth Material Number: R900933076

and:

• 4WREE 10 E25-2X/G24K31/A1V
• Rexroth Material Number: R900933073

Both are NG10, Series 2X valves with 24 VDC supply, K31 electrical connection and A1 ±10 V command input.

The key engineering advantage of the 4WREE is its combination of proportional solenoid actuation, electrical spool-position feedback and integrated electronics, enabling accurate and repeatable hydraulic flow control.

For replacement applications, our engineering approach focuses on in-situ interchangeability and 100% simulated operating-condition testing, with configuration matching based on spool symbol, nominal flow, mounting interface, electrical interface and seal material.

Technical Specifications

General 4WREE10 Specifications

• Manufacturer: Bosch Rexroth
• Series: 4WREE
• Type: Proportional directional valve
• Nominal Size: NG10
• Actuation: Direct-operated proportional solenoid
• Position Feedback: Electrical position feedback
• Electronics: Integrated valve electronics / OBE
• Mounting: Subplate mounting
• Interface: DIN 24 340 Form A / ISO 4401 / CETOP-RP 121 H
• Component Series: 2X
• Maximum Operating Pressure at P/A/B: 315 bar
• Maximum Pressure at T: 210 bar
• Maximum Permissible Flow, NG10: 180 L/min
• Fluid: Mineral oil HL/HLP according to DIN 51 524
• Fluid Temperature: -20°C to +80°C
• Preferred Fluid Temperature: +40°C to +50°C
• Viscosity Range: 20–380 mm²/s
• Preferred Viscosity: 30–46 mm²/s
• Maximum Contamination Level: ISO 4406 (C) 20/18/15
• Hysteresis: ≤0.1%
• Reversal Span: ≤0.05%
• Response Sensitivity: ≤0.05%
• Duty Cycle: 100%
• Maximum Coil Temperature: Up to 150°C
• Nominal Supply Voltage: 24 VDC
• Permissible Supply Voltage: 19.4–35 VDC
• Maximum Amplifier Current: <2 A
• Impulse Current: 3 A
• Protection: IP65 with correctly mounted and fixed connector
• Weight, NG10 4WREE: 6.5 kg.

Displacement and Rotational Speed

• Displacement: Not applicable.
• Maximum Rotational Speed: Not applicable.

The 4WREE10 is a hydraulic directional control valve rather than a pump or hydraulic motor.

4WREE 10 E1-50-2X/G24K31/A1V

• Full Model: 4WREE 10 E1-50-2X/G24K31/A1V
• Rexroth Material Number: R900933076
• Nominal Size: NG10
• Spool Symbol: E1
• Nominal Flow: 50 L/min
• Component Series: 2X
• Supply Voltage: 24 VDC
• Electrical Connection: K31
• Command Interface: A1
• Command Value Input: ±10 VDC
• Seal Type: V, FKM seals
• Maximum Operating Pressure, P/A/B: 315 bar
• Maximum T-Port Pressure: 210 bar
• Maximum Permissible Flow: 180 L/min
• Mounting: Subplate mounting
• Position Feedback: Electrical
• Integrated Electronics: Yes
• Weight: 6.5 kg for the NG10 4WREE configuration.

Rexroth’s published preferred-type list directly associates R900933076 with this exact valve configuration.

4WREE 10 E25-2X/G24K31/A1V

• Full Model: 4WREE 10 E25-2X/G24K31/A1V
• Rexroth Material Number: R900933073
• Nominal Size: NG10
• Spool Symbol: E
• Nominal Flow: 25 L/min
• Component Series: 2X
• Supply Voltage: 24 VDC
• Electrical Connection: K31
• Command Interface: A1
• Command Value Input: ±10 VDC
• Seal Type: V, FKM seals
• Maximum Operating Pressure, P/A/B: 315 bar
• Maximum T-Port Pressure: 210 bar
• Maximum Permissible Flow: 180 L/min
• Mounting: Subplate mounting
• Position Feedback: Electrical
• Integrated Electronics: Yes
• Weight: 6.5 kg for the NG10 4WREE configuration.

Rexroth’s published preferred-type list directly associates R900933073 with this exact valve configuration.

Key Technical Advantages

1. Direct-Operated Proportional Control

The 4WREE uses proportional solenoids to continuously position the control spool rather than simply switching the hydraulic path on or off.

This allows proportional adjustment of flow direction and magnitude, making the valve suitable for speed, position and actuator-control applications.

2. Electrical Position Feedback

The integrated position feedback system measures actual spool position.

This improves proportional-control consistency and helps achieve low hysteresis and high response sensitivity. Rexroth specifies:

• Hysteresis: ≤0.1%
• Reversal span: ≤0.05%
• Response sensitivity: ≤0.05%.

3. Integrated OBE Electronics

The WREE version integrates the valve electronics directly into the valve assembly.

Compared with the externally amplified WRE version, this simplifies the control architecture and reduces the need for a separate external proportional amplifier.

4. Servo-Quality Spool and Sleeve

Rexroth specifies the control spool and sleeve in servo quality.

This precision relationship is important for minimizing internal leakage while maintaining repeatable spool positioning and stable proportional flow characteristics.

5. Low Hysteresis and High Sensitivity

The official technical data demonstrate a high level of proportional-control precision.

This is particularly valuable in applications requiring stable actuator speed, smooth directional transition and repeatable hydraulic positioning.

6. Multiple NG10 Flow Configurations

The NG10 family includes nominal-flow configurations such as 25, 50 and 75 L/min.

Therefore, the E25 and E1-50 versions provide different nominal flow characteristics on the same NG10 platform, allowing better optimization according to system flow demand.

Application Areas

Typical applications include:

• Injection molding machines
• Hydraulic presses
• Forming equipment
• Machine tools
• Industrial hydraulic power units
• Automated hydraulic systems
• Hydraulic cylinder speed control
• Hydraulic cylinder positioning
• Hydraulic motor speed control
• Production and test equipment
• Electro-hydraulic control systems
• Industrial proportional hydraulic circuits

Rexroth documentation specifically describes the 4WREE as a solution for hydraulic flow-direction and flow-magnitude control in electro-hydraulic systems.

Expert Maintenance Tips

1. Verify the ±10 V Command Signal

The specified models use the A1 electrical interface.

Rexroth defines A1 as a ±10 V command-value input, while F1 corresponds to 4–20 mA. These interfaces should not be interchanged without verifying the controller architecture.

2. Match 25 L/min and 50 L/min Versions Correctly

The E25 and E1-50 versions have different nominal flow ratings:

• E25: 25 L/min
• E1-50: 50 L/min

Even though they share the NG10 platform and the same series-level maximum permissible flow, their actual control characteristics and pressure losses differ.

3. Maintain Hydraulic Cleanliness

The specified contamination limit is ISO 4406 (C) 20/18/15.

Proper filtration is important for protecting the precision spool, sleeve and position-feedback mechanism.

4. Control T-Port Back Pressure

The maximum specified T-port pressure is 210 bar.

Return-line restrictions, undersized piping or transient pressure spikes should therefore be eliminated during system design and maintenance.

5. Inspect the Mounting Interface During Replacement

Because the 4WREE10 is a subplate-mounted valve, the replacement process should verify:

• Mounting hole pattern
• Port arrangement
• Spool symbol
• Electrical connector
• Component series
• Seal material

This is essential for genuine in-situ interchangeability.

6. Verify Zero Position and Feedback After Service

After replacement or maintenance, verify the zero command, positive and negative command directions and the actual feedback signal.

Rexroth’s A1 interface documentation defines the command and actual-value signal paths, allowing the complete proportional control loop to be checked during commissioning.