DB20-2-53/315 Relief Valve | Rexroth DB DR Series | Pilot-operated Pressure Valve

LIC Hydraulic’s DB20 Series is a heavy-duty pilot-operated pressure relief valve, part of the industry-standard DB/DR Series (Sizes 10, 20, 30). This valve is engineered to regulate and limit maximum system pressure with extreme precision. The DB20-2-53/315 model offers 100% seamless interchangeability with Bosch Rexroth standards. Featuring a subplate mounting design, each valve undergoes 100% operational load testing to ensure a high crack-pressure accuracy and a leak-free re-seat, even in continuous-duty industrial environments.

Technical Specifications

• Model Code: DB20-2-53/315

• Nominal Size: Size 20

• Valve Type: Pilot-operated Pressure Relief

• Mounting Type: 2 (Subplate mounting)

• Design Series: 5X Series (53 variant)

• Max Set Pressure: 315 bar (4570 psi)

• Max Flow Rate: 500 L/min (132 gpm)

• Adjustment: Hand knob or hex screw with protective cap

• Fluid Compatibility: Mineral oils (HL, HLP) per DIN 51524

• Weight: Approx. 4.8 kg

Key Technical Advantages

• Superior Pressure Stability: The pilot-operated architecture ensures minimal pressure overrides regardless of flow fluctuations, maintaining a steady pressure ceiling for the entire circuit.

• Fast Response & Low Hysteresis: Precision-lapped main spools and pilot seats allow for rapid opening and closing, providing excellent protection against sudden pressure spikes.

• Integrated Unloading Options: Compatible with solenoid-operated directional valves (DBW type) for remote electrical unloading, enhancing system flexibility.

• Hardened Pilot Stages: The pilot poppet is manufactured from high-grade hardened steel, ensuring long-term resistance to erosion and maintaining sealing integrity over millions of cycles.

Application Areas

• Industrial Hydraulic Presses: Safety overload protection and constant pressure maintenance.

• Heavy-Duty HPUs: Core pressure regulation for large-scale hydraulic power units.

• Machine Tools: Accurate pressure control for clamping and feeding mechanisms.

• Metallurgical Plants: Robust pressure solutions for high-temperature and high-vibration environments.

Expert Maintenance Tips

• Strict Filtration: The small pilot orifices are sensitive to debris. Maintain fluid cleanliness at ISO 19/17/14 or better to prevent erratic pressure behavior or valve blockage.

• Torque Accuracy: When installing onto a subplate, use a torque wrench and follow a star pattern to avoid body distortion, which can cause spool binding.

• Spring Inspection: In high-cycle applications, inspect the pilot spring every 24 months for signs of fatigue to ensure your safety set-points remain accurate.