DBEM20-51/200XYG24NK4M Rexroth Proportional Relief Valve 350 bar

I. DBEM20-51/200XYG24NK4M Pilot-Operated Proportional Pressure Relief Valve

Product Overview

The DBEM20-51/200XYG24NK4M is a pilot-operated proportional pressure relief valve from Bosch Rexroth’s DBEM series, sized NG20/NG25 with subplate mounting .

DBEM series proportional pressure relief valves are used for stepless limitation of system pressure. They basically consist of a housing (1) with main spool insert (3) , a sandwich plate valve with maximum pressure limitation (2) , and a proportional pilot control valve (11) . The valve operates by applying pressure to port P, which acts on the main spool while also being directed to the spring-loaded side of the spool through control lines with nozzles. This pressure is applied to the poppet of the proportional pilot control valve, where it counteracts the force from the proportional solenoid. When hydraulic force overcomes solenoid force, the pilot poppet opens, allowing pilot oil to flow through the control line into port Y and then to tank—creating a pressure drop that enables the main spool to regulate operating pressure at port P .

The “XY” code indicates external pilot oil return with bleed port X, effectively preventing back pressure interference with the set pressure . The “N” code indicates no integrated pressure sensor . The “K4M” indicates the sandwich plate valve configuration with maximum pressure limitation .

As a direct replacement solution for the Bosch Rexroth DBEM series, this product strictly complies with Rexroth RE 29361 technical standards  and offers complete interchangeability—direct drop-in replacement without any modification to mounting dimensions or piping connections. Every unit undergoes 100% simulated duty cycle testing prior to shipment, ensuring performance reliability and long-term operational stability under actual working conditions.

Technical Specifications

• Model: DBEM20-51/200XYG24NK4M

• Series: DBEM (Pilot-operated Proportional Pressure Relief Valve)

• Brand: Bosch Rexroth

• Nominal Size: 20 (NG20/NG25) 

• Component Series: 5X (series 50–59, unchanged installation dimensions)

• Mounting Type: Subplate Mounting

• Porting Pattern Standard: ISO 6264 

• Maximum Operating Pressure: 350 bar 

• Pressure Setting Range: Up to 200 bar (code “200”)

• Maximum Flow Rate: 400 L/min 

• Control Type: Pilot-operated, proportional solenoid

• Solenoid Supply Voltage: 24 V DC (code “G24”)

• Pilot Oil Return: External pilot oil return with bleed port X (code “XY”) 

• Integrated Pressure Sensor: No (code “N”)

• Maximum Pressure Limitation: Integrated spring-loaded relief valve (code “K4M”) 

• Hydraulic Fluid: Mineral-oil-based (HL, HLP)

• Seal Material: NBR

• Weight: Approx. 3.8 kg 

• Bolt Height: 26 mm 

Key Technical Advantages

1. Pilot-Operated Proportional Control – Stepless, Precise Pressure Regulation
The DBEM20 combines a pilot-operated design with a proportional solenoid, enabling continuous, stepless system pressure setting via electrical command signals . The pressure-command value characteristic curve offers excellent linearity, delivering bar-level precision in hydraulic system pressure limiting applications .

2. Integrated Maximum Pressure Limitation – Dual Safety Protection
This model features a spring-loaded maximum pressure limitation valve (sandwich plate valve) preset to a specific safety pressure value . Should system pressure exceed this safety limit for any reason (proportional solenoid failure, command signal abnormality, etc.), the valve automatically opens, diverting oil to tank via port Y . This mechanical safety redundancy ensures system pressure never exceeds the safety limit—even under electrical fault conditions.

3. XY-Type External Pilot Oil Return – Eliminates Back Pressure Interference
The “XY” code indicates external pilot oil return with bleed port X . Pilot control valve leakage and pilot return oil are directed to tank via independent X/Y ports—completely isolated from system return line back pressure. This ensures the set pressure is unaffected by return back pressure fluctuations, guaranteeing precision and stability of pressure control.

4. High Flow Capacity – Meets Large System Demands
The DBEM20 delivers 400 L/min flow capacity in the NG20/NG25 envelope , meeting the relief requirements of large industrial hydraulic systems, metallurgical equipment, and heavy presses. The 350 bar maximum operating pressure ensures reliable operation in high-pressure, heavy-load applications .

5. Flexible Subplate Mounting with Standardized Interface
Features subplate mounting per ISO 6264  for direct installation onto standard valve manifolds. The standardized interface ensures plug-and-play compatibility with existing systems—no adapters or converters required.

Application Areas

• Large Hydraulic System Pressure Limiting: Main system relief with precise stepless pressure setting

• Injection Molding Machinery: Multi-stage injection pressure control and safety limiting

• Heavy Hydraulic Presses & Die-Casting: Stepless press force regulation and safety protection

• Metallurgical Equipment: Pressure control and overpressure protection in rolling mill hydraulics

• Test Rigs & Laboratory Equipment: Precise pressure profile simulation for hydraulic test systems

• Marine & Offshore: Pressure limiting and safety protection for large hydraulic systems

Expert Maintenance Tips

1. Mounting Surface Verification
DBEM20 conforms to ISO 6264. Thoroughly clean the mounting surface prior to installation. Inspect O-ring seals for aging or damage—replace after every disassembly.

2. Port Y and Port X (Drain Ports) – Independent Tank Return
For XY-type configurations, pilot return oil (port Y) and leakage oil (port X) must be independently returned to tank and must not be parallel-connected with return lines from other valves . Excessive back pressure at ports Y and X will cause setpoint drift and reduced control accuracy.

3. Proportional Amplifier Selection
DBEM series requires an external proportional amplifier (e.g., VT-VSPA series) for operation . Ensure the amplifier output current matches the solenoid specification (code “K4M” corresponds to a specific current rating). Genuine Rexroth amplifiers are recommended for optimal control characteristics.

4. Solenoid Electrical Connection
Supply voltage is 24 V DC—use a stable DC power supply. Shielded cables are recommended to minimize electromagnetic interference with command signals.

5. Scheduled Maintenance
Perform preventive maintenance every 2,000 operating hours:

• Verify cracking pressure matches command value

• Check maximum pressure limitation function

• Inspect ports Y and X for blockage or abnormal back pressure

• Inspect solenoid coil resistance and insulation

• Inspect O-ring seals for aging or damage

II. DBEME10-70/200YG24K31M Pilot-Operated Proportional Pressure Relief Valve (with Integrated On-Board Electronics)

Product Overview

The DBEME10-70/200YG24K31M is a pilot-operated proportional pressure relief valve from Bosch Rexroth’s DBEME series, sized NG10 with subplate mounting .

The defining feature of the DBEME series is the integration of OBE (On-Board Electronics) . Unlike the DBEM series which requires an external amplifier, the DBEME series integrates the proportional amplification function directly onto the valve body—users simply provide 24 V DC power and a 0–10 V (or 4–20 mA) command signal to drive the valve, significantly simplifying system wiring and commissioning .

The DBEME series shares the same basic construction as the DBEM series: a housing (1) with main spool insert (3) , a sandwich plate valve with maximum pressure limitation (2) , and a proportional pilot control valve (11) . However, the DBEME series integrates a position sensor and closed-loop control electronics on the proportional pilot control valve, enabling closed-loop control of the pilot spool position for superior control accuracy and repeatability .

The “E” code indicates integrated on-board electronics (OBE) . The “31” code indicates a specific integrated electronics configuration . The “M” code indicates the sandwich plate valve configuration with maximum pressure limitation .

As a direct replacement solution for the Bosch Rexroth DBEME series, this product strictly complies with Rexroth RE 29362 technical standards  and offers complete interchangeability—direct drop-in replacement without any modification to mounting dimensions or electrical connections. Every unit undergoes 100% simulated duty cycle testing prior to shipment, ensuring performance reliability and long-term operational stability under actual working conditions.

Technical Specifications

• Model: DBEME10-70/200YG24K31M

• Series: DBEME (Pilot-operated Proportional Pressure Relief Valve with OBE)

• Brand: Bosch Rexroth

• Nominal Size: 10 (NG10) 

• Component Series: 7X (series 70–79, unchanged installation dimensions)

• Mounting Type: Subplate Mounting

• Porting Pattern Standard: ISO 6264 

• Maximum Operating Pressure: 350 bar 

• Pressure Setting Range: Up to 200 bar (code “200”)

• Maximum Flow Rate: 200 L/min 

• Control Type: Pilot-operated, proportional solenoid with integrated OBE

• Supply Voltage: 24 V DC (code “G24”)

• Command Signal: 0–10 V or 4–20 mA (configuration dependent)

• Pilot Oil Return: External pilot oil return (code “Y”) 

• Maximum Pressure Limitation: Integrated spring-loaded relief valve (code “M”) 

• Integrated Electronics Configuration: Code “31” 

• Hydraulic Fluid: Mineral-oil-based (HL, HLP)

• Seal Material: NBR

• Weight: Approx. 3.5 kg 

• Bolt Height: 26 mm 

Key Technical Advantages

1. Integrated OBE Electronics – Plug-and-Play, Simplified System Design
The greatest advantage of the DBEME series is the on-board electronics (OBE) integration . Users no longer need to source and install external proportional amplifiers—simply provide 24 V DC power and a standard 0–10 V or 4–20 mA command signal to drive the valve directly. This significantly simplifies system wiring, reduces control cabinet space requirements, and lowers commissioning complexity and time.

2. Closed-Loop Position Control – Superior Accuracy & Repeatability
The integrated electronics implement closed-loop control of the pilot spool position, continuously monitoring and correcting position deviations . Compared to the open-loop DBEM series, the DBEME series delivers significantly improved pressure control accuracy, repeatability, and reduced hysteresis—making it ideal for applications with demanding precision requirements.

3. Low Manufacturing Tolerance in Command Value-Pressure Characteristics
Rexroth DBEME series integrated electronics are precision-calibrated, resulting in extremely low manufacturing tolerances in the command value-pressure characteristic curve . This means different valves of the same model offer exceptional consistency—eliminating the need for individual pressure calibration on each machine in batch equipment manufacturing, substantially saving production and commissioning time.

4. Integrated Maximum Pressure Limitation – Dual Safety Protection
This model features a spring-loaded maximum pressure limitation valve, preset to a specific safety pressure value . Should system pressure exceed this safety limit for any reason (electronics failure, command signal abnormality, etc.), the valve automatically opens, diverting oil to tank via port Y . This mechanical safety redundancy ensures system pressure never exceeds the safety limit—even under electrical fault conditions.

5. Compact NG10 Size – High Power Density
Delivers 200 L/min flow capacity and 350 bar pressure rating in the compact NG10 envelope . This high power density enables precise control of high flow and high pressure within limited installation space—ideal for modern compact hydraulic systems with stringent space constraints.

Application Areas

• Injection Molding Machinery: Precision closed-loop control of multi-stage injection pressures

• Hydraulic Presses & Die-Casting: High-precision stepless press force regulation and safety protection

• Machine Tool Hydraulic Systems: Precise pressure control for tool feed and table motion

• Test Rigs & Laboratory Equipment: High-accuracy pressure simulation for hydraulic test systems

• Mobile Machinery: Precise pressure limiting for implement control circuits

• Industrial Automation Lines: High-repeatability pressure control for various hydraulic systems

Expert Maintenance Tips

1. Mounting Surface Verification
DBEME10 conforms to ISO 6264. Thoroughly clean the mounting surface prior to installation. Inspect O-ring seals for aging or damage—replace after every disassembly.

2. Electrical Connection
Supply voltage is 24 V DC—use a stable DC power supply. Command signal lines should use shielded twisted-pair cables with the shield single-point grounded at the controller end to minimize electromagnetic interference.

3. Port Y (Drain Port) – Independent Tank Return
Pilot return oil (port Y) must be independently returned to tank and must not be parallel-connected with return lines from other valves . Excessive back pressure at port Y will cause setpoint drift and reduced control accuracy.

4. Initial Commissioning & Parameter Setting
Before initial power-up, verify supply voltage and command signal type match the valve configuration. Perform pressure-command value calibration under actual system operating temperature and flow conditions using a precision pressure gauge at port P.

5. Electromagnetic Compatibility (EMC) Considerations
DBEME series integrated electronics are sensitive to electromagnetic interference. Ensure:

• Valve body is properly grounded to the manifold

• Power and signal cables are routed separately—avoid parallel runs

• Shielded cables compliant with EMC requirements are used

• A power line filter may be installed at the power input

6. Scheduled Maintenance
Perform preventive maintenance every 2,000 operating hours:

• Verify cracking pressure matches command value

• Check maximum pressure limitation function

• Inspect port Y for blockage or abnormal back pressure

• Inspect electrical connections for looseness, oxidation, or corrosion

• Inspect O-ring seals for aging or damage