4WEH16E7X/6EG24N9ETK4/B10 Rexroth Valve 280 Bar

Product Overview

The Bosch Rexroth 4WEH16E7X/6EG24N9ETK4/B10 is a pilot-operated electro-hydraulic directional spool valve for controlling the start, stop and direction of hydraulic flow in high-flow industrial hydraulic systems.

It belongs to the Rexroth WEH family, which is designed for subplate mounting and ISO 4401 interfaces. The family covers nominal sizes NG10 to NG32 and is available with internal or external pilot oil supply and return configurations.

The exact configuration corresponds to Bosch Rexroth material number R900923971. Exact-part records identify the valve as a size 16, E-symbol, 3-position, 24 V DC solenoid-operated WEH directional valve with NBR seals.

The ordering code can be interpreted as follows:

• 4: 4-way version
• WEH: electro-hydraulic actuation
• 16: NG16 nominal size
• E: E spool symbol
• 7X: component series 7X
• 6E: high-power pilot control valve
• G24: 24 V DC solenoid
• N9: concealed manual override
• ET: internal pilot oil supply and internal pilot oil return
• K4: DIN EN 175301-803 electrical connector
• B10: 1.0 mm throttle insert
• No V suffix: standard NBR sealing configuration.

A critical engineering point is the pressure rating. The exact model does not contain the prefix H. Rexroth specifies the standard version without H for maximum operating pressure up to 280 bar, while the H-prefixed configuration is the version rated up to 350 bar. Therefore, this exact model should be marketed as a 280 bar valve, not a 350 bar valve.

Technical Specifications

• Model: 4WEH16E7X/6EG24N9ETK4/B10
• Bosch Rexroth Material Number: R900923971
• Valve Type: Pilot-operated electro-hydraulic directional spool valve
• Configuration: 4-way directional valve
• Nominal Size: NG16
• Mounting Standard: ISO 4401-07-07-0-05
• CETOP Size: CETOP 07
• Spool Symbol: E
• Switching Positions: 3
• Main Spool Return: Spring-centered
• Actuation: Electro-hydraulic pilot control
• Pilot Control Valve: 6E high-power valve
• Pilot Oil Supply: Internal
• Pilot Oil Return: Internal
• Supply Voltage: 24 V DC
• Manual Override: N9 concealed manual override
• Electrical Connection: K4, DIN EN 175301-803
• Throttle Insert: B10, Ø1.0 mm
• Seal Material: NBR
• Maximum Operating Pressure at P/A/B: 280 bar
• Maximum Internal Pilot Return / T Pressure, DC WEH: 210 bar
• Maximum Flow for NG16, E spool: 300 L/min under the specified Rexroth performance test conditions; the actual application point must be checked against pressure-drop characteristics.
• Minimum Pilot Pressure for Internal Supply, NG16, 3-position Spring-Centered: 14 bar
• Maximum Pilot Pressure: 250 bar
• Approximate Pilot Flow for Shortest Switching Time, NG16: 35 L/min
• Hydraulic Fluid Temperature: -20 to +80 °C with NBR seals
• Ambient Temperature: -20 to +50 °C with NBR seals
• Permitted Viscosity: 2.8 to 500 mm²/s
• Maximum Fluid Contamination: ISO 4406 Class 20/18/15
• Base Valve Weight, NG16, Two Solenoids, Spring-Centered: approximately 8.9 kg; exact-part commercial records list approximately 9.78 kg, so shipping weight should be confirmed against the delivered configuration.
• Displacement: Not applicable
• Maximum Speed: Not applicable
• Peak Pressure: No separate peak-pressure value is specified as a standalone rating; the applicable maximum operating pressure is 280 bar.

Key Technical Advantages

1. Pilot-operated architecture for high-flow control

The WEH design uses a pilot valve to hydraulically control the main spool.

This architecture separates the pilot control function from the main hydraulic flow path, allowing the valve to handle substantially larger main flows than a conventional directly operated valve. Rexroth specifies the WEH family for applications up to 1100 L/min depending on nominal size and configuration.

2. Up to 300 L/min NG16 performance capability

For the NG16 E-spool configuration, Rexroth’s official performance limits specify up to 300 L/min under defined HLP46 test conditions.

Actual machine selection should still be based on the real operating pressure, flow rate, pressure drop and hydraulic-fluid temperature rather than using the maximum flow value alone.

3. 7X series dimensional continuity

Rexroth states that the 7X component series maintains the corresponding installation and connection dimensions for the applicable NG16 versions.

This is particularly valuable for modernization and replacement projects because the existing manifold interface can often be retained while the valve itself is replaced, subject to complete function verification.

4. Internal ET pilot circuit

The ET configuration uses internal pilot oil supply from the main P channel and internal pilot oil return through the T channel.

This simplifies external piping and is well suited to compact industrial valve assemblies. Rexroth explicitly defines the ET configuration as internal supply and internal return.

5. Integrated B10 throttle insert

The B10 Ø1.0 mm throttle insert is an important element of the internal pilot circuit.

Rexroth specifies the throttle insert for internal pilot supply to limit pilot flow and prevent inadmissibly high pressure peaks. Consequently, the B10 configuration affects dynamic valve behavior and should not be removed or substituted arbitrarily.

6. 24 V DC control with concealed manual override

The G24 version uses 24 V DC electrical control, while N9 provides a concealed manual override for commissioning and emergency servicing.

This combination is practical for industrial control cabinets where 24 V DC control is standard and local manual testing is required.

7. High-precision spool-control engineering

From a hydraulic engineering perspective, long-term performance depends on accurate spool-to-bore matching, internal passage geometry, throttle-orifice consistency and contamination control.

For replacement manufacturing, the critical engineering parameters therefore extend beyond the external envelope and include the spool metering edges, internal leakage characteristics, pilot circuit and spring-centering behavior.

8. Suitable for OEM interchangeability programs

For R900923971 / 4WEH16E7X/6EG24N9ETK4/B10, successful replacement engineering should verify:

• NG16 / CETOP 07 mounting interface
• E spool function
• Three-position spring-centered configuration
• 24 V DC solenoids
• N9 manual override
• ET internal pilot supply and return
• K4 electrical connector
• B10 Ø1.0 mm throttle insert
• NBR seals
• 280 bar maximum operating pressure

Our replacement engineering can focus on Interchangeability at both the mechanical and functional levels, followed by 100% simulated operating-condition testing covering switching, pressure, flow, temperature and continuous operation.

Application Areas

Typical applications include:

• Hydraulic presses
• Injection molding machines
• Die-casting equipment
• Forging and metal-forming machinery
• Steel and metallurgical hydraulic systems
• Industrial automation hydraulic stations
• Hydraulic clamping systems
• Heavy-duty machine tools
• Hydraulic lifting systems
• Hydraulic power units
• Integrated hydraulic manifolds
• OEM multi-valve hydraulic control systems

The valve is particularly suitable where large actuator flow must be controlled through an electrically commanded pilot-operated directional valve.

Expert Maintenance Tips

1. Verify the internal pilot pressure requirement

Because this exact configuration uses internal pilot supply, the P-port pressure must be sufficient to operate the pilot stage.

For the NG16 three-position spring-centered configuration, Rexroth specifies a minimum internal pilot pressure of 14 bar. If the machine cannot consistently provide this pressure, the pilot circuit configuration should be reassessed instead of attempting to compensate electrically.

2. Do not change the B10 throttle arbitrarily

The B10 insert is a 1.0 mm throttle and forms part of the specified ET configuration.

Changing its diameter can alter pilot flow, switching dynamics and pressure peaks. Rexroth specifically identifies B10 as necessary for limiting pilot flow in internal-pilot configurations.

3. Distinguish 280 bar from 350 bar versions

This is critical during procurement and replacement.

4WEH16E7X/… = up to 280 bar

H-4WEH16E7X/… = up to 350 bar

The absence of the H prefix must therefore be preserved when specifying an equivalent replacement.

4. Monitor T-port back pressure

For the DC-voltage WEH configuration with internal pilot return, Rexroth specifies a maximum T pressure of 210 bar.

Return-line back pressure must therefore be checked during commissioning, particularly in common-return manifolds where dynamic pressure can rise during simultaneous valve switching.

5. Maintain hydraulic cleanliness

The specified maximum cleanliness level is ISO 4406 Class 20/18/15.

Contamination may increase spool friction, delay shifting, increase leakage or cause incomplete main-spool movement even when the solenoid is energized. Effective filtration is therefore essential for service life and switching reliability.

6. Validate dynamic operation after replacement

After installation, testing should include:

• P-port pressure verification
• A/B directional switching
• center-position verification
• low-flow and high-flow testing
• multiple operating-pressure points
• solenoid and manual-override checks
• thermal stabilization
• continuous operation

For OEM replacement products, 100% simulated operating-condition testing provides a stronger validation method than a simple static bench pressure test.