DBW10B1-52/315-6EG24N9K4 | Rexroth Solenoid Relief Valve 350bar 650L/min

Product Overview

The DBW10B1-52/315-6EG24N9K4 and DBW10A-2-50/200-6AG24Z5L are classic models in the Bosch Rexroth DBW series of pilot-operated solenoid relief valves, NG10 (CETOP 5) size. The DBW series adds a solenoid directional valve to the DB series relief valve, enabling system pressure limiting and remote solenoid-actuated unloading.

The DBW series valve consists of three main components: the main valve (with main spool insert), the pilot control valve (with pressure adjustment element), and the integrated directional spool valve. Both models feature B spool symbol (P→T flow path) with 52 Series design.

Model Code Breakdown (DBW10B1-52/315-6EG24N9K4)：

• DBW: Pilot-operated pressure relief valve with solenoid unloading

• 10: Nominal Size NG10 (10 mm)

• B1: Spool symbol and configuration (B type, P→T)

• 52: Series design (52 Series)

• 315: Maximum pressure setting (315 bar)

• 6E: With wet-type solenoid

• G24: DC 24V supply

• N9: With manual override

• K4: Without cable socket

Model Code Breakdown (DBW10A-2-50/200-6AG24Z5L)：

• DBW: Pilot-operated pressure relief valve with solenoid unloading

• 10: Nominal Size NG10 (10 mm)

• A-2: Spool symbol and configuration (A type)

• 50: Series design (50 Series)

• 200: Maximum pressure setting (200 bar)

• 6A: With wet-type solenoid

• G24: DC 24V supply

• Z5L: Option code (specific configuration)

As original Bosch Rexroth DBW series pilot-operated solenoid relief valves, these products offer complete interchangeability within the same series and size, requiring no modifications to mounting interfaces or piping layouts.

Technical Specifications 

DBW10B1-52/315-6EG24N9K4 Specifications:

• Model: DBW10B1-52/315-6EG24N9K4

• Material Number: R900920863

• Brand: BOSCH REXROTH

• Series: DBW Series, 52 Series Design

• Product Type: Pilot-operated Solenoid Relief Valve

• Spool Symbol: B type (P→T) 

• Nominal Size: NG10 (10 mm)

• Mounting Standard: ISO 6264-06-09 / NFPA T3.5.1 R2-2002 D05

• Mounting Type: Subplate Mounting

• Maximum Operating Pressure: 350 bar (5000 psi) 

• Maximum Flow Rate: 650 L/min

• Maximum Pressure Setting: 315 bar (4569 psi)

• Coil Voltage: 24V DC

• Electrical Connector: DIN EN 175301-803

• Seal Material: NBR

• Hydraulic Fluids: HL, HLP, HLPD, HVLP, HVLPD, HFC

• Connection Type: Threaded

• Body Material: Cast Iron

• Weight: Approx. 2.6 kg（4.97 kg for certain configurations）

DBW10A-2-50/200-6AG24Z5L Specifications:

• Model: DBW10A-2-50/200-6AG24Z5L

• Material Number: R900523062

• Brand: BOSCH REXROTH

• Series: DBW Series, 50 Series Design

• Product Type: Pilot-operated Solenoid Relief Valve

• Spool Symbol: B type (P→T)

• Nominal Size: NG10 (10 mm)

• Mounting Standard: ISO 6264-06-09

• Mounting Type: Subplate Mounting

• Maximum Operating Pressure: 350 bar (5000 psi)

• Maximum Flow Rate: 650 L/min

• Maximum Pressure Setting: 200 bar (2900 psi)

• Coil Voltage: 24V DC

• Option Code: Z5L

• Seal Material: NBR (standard)

• Hydraulic Fluids: HL, HLP, HLPD, HVLP, HVLPD, HFC

• Body Material: Cast Iron

Key Technical Advantages

1. Pilot-Operated Design — High-Pressure High-Flow with Precise Control

The DBW10 series features pilot-operated construction—the main valve is controlled by a pilot control valve. Compared to direct-acting relief valves, the pilot-operated design delivers superior pressure/flow stability, lower hysteresis, and more precise pressure control. Maximum flow reaches 650 L/min, placing it at the forefront of relief valves in its class.

2. Integrated Solenoid Unloading — Remote Pressure Control

The DBW series adds a solenoid directional valve to the DB series relief valve, enabling remote solenoid-actuated system pressure unloading. When energized, the directional valve actuates, unloading system pressure to tank through the pilot valve. This allows the DBW valve to serve both as a system safety valve and a remote unloading valve.

3. B Spool Symbol — Direct P→T Unloading Flow Path

Both models feature B spool symbol (P→T flow path) . When the solenoid is energized, pressure oil at the P port flows directly to the T port for rapid system pressure release. The B configuration is ideal for applications requiring direct unloading to tank.

4. Multiple Pressure Grades with Various Adjustment Types

The DBW10 series offers multiple pressure grades. DBW10B1-52/315-6EG24N9K4 provides a maximum setting of 315 bar. DBW10A-2-50/200-6AG24Z5L provides a maximum setting of 200 bar. 4 adjustment types are available: rotary knob, sleeve with hexagon and protective cap, lockable rotary knob with scale, and rotary knob with scale.

5. NBR Seals with Multi-Fluid Compatibility

Equipped with NBR seals, compatible with HL, HLP, HLPD, HVLP, HVLPD, HFC, and other hydraulic fluids. Suitable for mineral oil and water-containing fluid systems, meeting diverse industrial application requirements.

6. International Standard Compliance for Global Interchangeability

Mounting conforms to ISO 6264-06-09 and NFPA T3.5.1 R2-2002 D05 standards. The DBW series offers complete interchangeability with globally adopted NG10 size interfaces for direct replacement of same-series, same-specification products.

Application Areas

• Fixed-Displacement Pump Systems — System pressure limiting and remote unloading control

• Injection Molding Machinery — System pressure setting and unloading

• Hydraulic Presses and Forging Equipment — System pressure limiting and remote unloading

• Die-Casting Machines — Pressure control for high-pressure casting equipment

• CNC Machine Tools — Hydraulic system pressure limiting and unloading

• Industrial Automation Production Lines — Hydraulic systems requiring remote pressure unloading

• Steel and Mining Equipment — Pressure control for rolling mills and heavy-duty systems

Expert Maintenance Tips

1. Installation Guidelines

• Mounting surface must conform to ISO 6264-06-09 and NFPA T3.5.1 R2-2002 D05 standards.

• Thoroughly clean the mounting surface and all ports (P, T) before installation to prevent foreign particles from entering and causing spool sticking or seal damage.

• Tighten mounting bolts evenly to the specified torque to ensure proper sealing between the valve body and mounting surface.

2. Hydraulic Fluid Cleanliness

• Compatible fluids: HL, HLP, HLPD, HVLP, HVLPD, HFC.

• Seal material: NBR.

• Install a return line filter with minimum 10 μm filtration rating.

3. Pressure Setting Adjustment

• DBW10B1-52/315-6EG24N9K4 maximum setting: 315 bar.

• DBW10A-2-50/200-6AG24Z5L maximum setting: 200 bar.

• Pressure adjustment is performed via the adjustment element on the pilot valve—turn clockwise to increase, counterclockwise to decrease.

• Adjust gradually under system operating conditions to achieve the desired pressure value.

4. Electrical Connection Specifications

• Both models use 24V DC supply.

• Electrical connector: DIN EN 175301-803 standard.

• Ensure the connector is fully locked to maintain effective protection.

5. Solenoid Unloading Function Usage

• When the DBW series solenoid is energized, system pressure is unloaded to tank pressure through the pilot valve.

• When de-energized, the valve returns to normal relief function.

• The unloading function can be used for system standby energy saving or emergency pressure release.

6. Periodic Maintenance Inspection

• Inspect the valve body for external oil leakage every 2,000 operating hours or at least annually.

• Check electrical connectors for looseness, oxidation, or moisture ingress.

• If pressure control instability or slow response is observed, first check system fluid cleanliness and verify the pilot spool is not sticking.