Rexroth DBD Series Relief Valve | DBDH6 DBDH10 DBDH20 | Hydraulic Pressure Control Valve

The DBD Series direct-operated relief valves from Chengyuan Hydraulic are high-performance pressure control components fully compatible with Rexroth industrial standards. These valves are primarily used to limit system pressure, serving as safety valves or pressure regulators. For core models such as DBDH6K, DBDH10K, and DBDH20G, we utilize high-hardness alloy steel spools and precision-ground seats. Every valve undergoes 100% full-load condition testing before shipment to ensure zero leakage and high sensitivity under frequent relief cycles, guaranteeing 100% original-place interchangeability.

Technical Specifications :

• Series Model: DBD Series (Direct-operated)

• Nominal Size: 6 (DBDH6), 10 (DBDH10), 15, 20 (DBDH20)

• Connection Type: K (Cartridge), G (Threaded/Subplate), P (Manifold)

• Max Operating Pressure: 400 bar (40 MPa)

• Adjustment Type: H (Handknob), S (Set screw with internal hexagon)

• Max Flow Rate: 50 L/min (Size 6) / 120 L/min (Size 10) / 250 L/min (Size 20)

• Temperature Range: -20°C to +80°C

• Sealing Material: NBR (Standard), FKM (Optional)

Key Technical Advantages:

• High-Pressure Direct-Acting Design: The DBD series features a simple yet robust sliding spool or poppet design, offering extremely fast response times. It opens instantaneously when system pressure exceeds the setpoint, preventing hydraulic shock from damaging pumps or cylinders.

• Premium Spring Material & Treatment: We use high-performance spring steel subjected to rigorous fatigue testing and tempering. This ensures minimal deviation between the reset and set pressures, even after prolonged exposure to 400 bar environments.

• Hardened Alloy Spool & Seat: Spools are vacuum heat-treated to a hardness of over HRC 60. Precision spherical grinding of the valve seat achieves a near “zero-leakage” metal-to-metal seal in the closed position.

• Optimized Damping Characteristics: The internal spool design incorporates precision damping orifices, effectively suppressing the whistling noise and pressure oscillations typical of direct-acting valves, ensuring a stable pressure envelope even under high-flow relief.

Application Areas:

• Compact Hydraulic Power Units: Serving as the main relief valve to regulate working pressure.

• Construction Machinery Circuits: Protecting actuators from instantaneous high-pressure spikes during obstacle encounters.

• Machine Tool Clamping: Maintaining constant clamping force.

• High-Pressure Test Benches: Providing reliable overload protection.

Expert Maintenance Tips:

• Adjustment Caution: When setting the pressure, do not force the adjustment screw to its limit. If you feel a sudden increase in resistance, the spring has reached its maximum stroke; further force may damage the internal mechanism.

• Fluid Cleanliness: Although direct-operated valves are more contamination-tolerant, hard particles lodged in the seat can prevent the system from building pressure. Maintain oil cleanliness at NAS Class 9 or better.

• Installation Check: For cartridge-type (K) valves, verify the mounting hole dimensions and O-ring integrity before installation to prevent lateral bypass leakage.