Product Overview
The DBET series is a direct-operated proportional pressure relief valve from Bosch Rexroth, featuring poppet/seat design. The DBET-51/200G24Z4M, DBET-52/50G24K4M, and DBET-62/350G24K4V are typical models within this series, covering different pressure ratings and component series. DBET-type proportional pressure relief valves are remote control valves with seat design and are used for system pressure limitation.
The valve is operated by a proportional solenoid with central thread and detachable coil. The interior of the solenoid is connected to port T or Y and is filled with hydraulic fluid. Dependent on the electric command value, these valves can be used to steplessly set the system pressure to be limited. The valves basically consist of housing, proportional solenoid, valve seat, and valve poppet.
Rated at NG6 with ISO 4401-03-02-0-05 mounting interface. As a direct OEM-replacement solution, this valve maintains 100% mechanical and functional interchangeability with the original Rexroth unit. Every valve undergoes rigorous simulation testing—including pressure cycling, thermal variation, and full-stroke endurance validation—to guarantee factory-grade performance.
Technical Specifications
DBET Series General Specifications (NG6):
Valve Type: Direct operated proportional pressure relief valve
Brand: Bosch Rexroth
Nominal Size: NG6
Mounting Interface: ISO 4401-03-02-0-05
Mounting Type: Subplate mounting
Design: Poppet / seat design
Max. Operating Pressure: 350 bar (DBET-51 / DBET-52); 420 bar (DBET-62)
Max. Flow: 2 L/min(3 L/min for some models)
Component Series: 1X (DBET-51); 52 (DBET-52, 50–59 series); 6X (DBET-62)
Control Type: Proportional solenoid direct actuation
Supply Voltage: 24 V DC
Electrical Connection: 3-pole (2 + PE) connector per DIN EN 175301-803
Seal Material: Z4M: NBR; K4M: NBR; K4V: FKM (Viton)
Compatible Fluids: Mineral oil (HL, HLP) per DIN 51524
Coil Current: 800 mA
Operating Temperature Range: -10°C to +50°C (reference)
Control Electronics: Requires external amplifier (e.g., VT5003, VT-VRPD-1 series)
Model-Specific Parameters:
DBET-51/200G24Z4M: Pressure rating 200 bar, Component series 1X (10–19 series), NBR seals (Z4M), 24 V DC
DBET-52/50G24K4M: Pressure rating 50 bar, Component series 52 (50–59 series), NBR seals (K4M), 24 V DC, Max. flow 3 L/min (at 50 bar pressure stage)
DBET-62/350G24K4V: Pressure rating 350 bar, Component series 6X (60–69 series), FKM seals (K4V), 24 V DC
Key Technical Advantages
1. Poppet/Seat Design – Superior Sealing Performance
The DBET series features poppet/seat design. Compared to spool-type designs, the poppet design offers superior internal leakage sealing performance, providing significant advantages in applications requiring long-term pressure holding or precise pressure limitation.
2. Direct-Operated Design – Fast Response with No Pilot Delay
The direct-operated structure, with proportional solenoid directly actuating the poppet, eliminates pilot stage requirements. Fast response and zero pressure regulation lag make it ideal for dynamic applications requiring rapid and precise pressure limitation.
3. Central Thread Solenoid with Detachable Coil – Easy Maintenance
The proportional solenoid features central thread and detachable coil, allowing coil replacement without opening the pressure-tight hydraulic chamber. The solenoid interior is connected to port T or Y and filled with hydraulic fluid, effectively lubricating moving parts and improving heat dissipation.
4. Stepless Pressure Setting – High Adjustment Precision
System limiting pressure can be steplessly set according to the electric command value. Paired with external amplifiers (e.g., VT5003, VT-VRPD-1 series), fine adjustment of the command value-pressure characteristic curve is achievable.
5. Drop-In Interchangeability – Minimized Downtime and Retrofit Costs
The valve strictly adheres to Bosch Rexroth’s original mounting dimensions and functional specifications, with ISO 4401-03-02-0-05 interface compliance. Whether for new system design or legacy system upgrades, this valve offers 100% mechanical and electrical interchangeability with the original Rexroth unit—eliminating the need for manifold modifications or piping changes, significantly reducing downtime and retrofit expenses.
Application Areas
Injection Molding Machinery – Precise system pressure limitation and regulation
Hydraulic Presses – Stepless setting and limitation of maximum system working pressure
Machine Tool Hydraulic Systems – Remote pressure control for precise system pressure regulation
Metallurgical Equipment – System pressure limitation in rolling mill hydraulic systems
Test Rigs and Testing Equipment – Precisely adjustable system pressure for laboratory and production testing
Industrial Automation Lines – Pressure protection and precise limitation for hydraulic systems
Expert Maintenance Tips
1. Fluid Cleanliness Management
DBET series proportional relief valves feature poppet design where the sealing interface between valve seat and poppet is sensitive to contaminants. Maintain system fluid cleanliness to ISO 4406 18/16/13 or better. Install filters with a minimum rating of 10μm upstream of the valve.
2. Electrical Connections and Amplifier Matching
DBET series valves require external amplifiers (e.g., VT5003, VT-VRPD-1 series). Verify that amplifier output parameters match the valve’s electrical specifications—coil current 800 mA, supply voltage 24 V DC. Electrical connection uses 3-pole (2 + PE) connector per DIN EN 175301-803.
3. Seal Material Compatibility
DBET series offers NBR (code M) or FKM/Viton (code V) seal options. Confirm that the selected seal material is compatible with the hydraulic fluid used in the system. NBR is suitable for mineral oils (HL, HLP), while FKM offers broader compatibility including fire-resistant fluids such as phosphate esters.
4. Return Line Backpressure Control
The solenoid interior is connected to port T or Y and filled with hydraulic fluid. Ensure the return line maintains proper backpressure and remains oil-filled to prevent air entrapment in the solenoid chamber, which could affect thrust characteristics.
5. Installation and Commissioning
Carefully review the Bosch Rexroth product documentation (RE29170) prior to installation. Ensure the mounting surface is flat and smooth, and tighten mounting bolts evenly to specified torque. During initial commissioning, test valve operation with low command value signals first, then gradually increase to the required set pressure. Independently adjustable upward and downward ramps are available through the external amplifier.
