Technical Parameter Table: Rexroth Cartridge-Type Pilot-Operated Relief Valve DBDH10K1X/315

FAQ: Rexroth Cartridge Relief Valve DBDH10K1X/315

1. Product Identification & Selection

Q1: What does the "315" in the model code DBDH10K1X/315 mean?

A:​ It signifies the valve's standard factory pressure setting of 315 bar. This is the primary pressure rating and a critical parameter for selection.

Q2: What do the codes "1X" and "K" in the model number stand for?

A:

• 1X:​ Indicates the adjustment method is "without handwheel". Pressure must be adjusted using a hex key at the rear of the cartridge.

• K:​ Indicates the adjustment screw is equipped with a protective cap​ to shield it from contamination and accidental adjustment.

Q3: How do I order spare parts or a replacement using this model?

A:​ The primary Rexroth article number is R900424183. This is the most accurate and unique code for global spare parts inquiries and orders. You can also quote the full model number DBDH10K1X/315​ for requests and verification.

Q4: How is this valve different from a standard inline relief valve?

A:​ The key difference is the mounting style. The DBDH is a cartridge (plug-in) valve​ that must be installed into a precision-machined cavity within a manifold block. This allows for high integration, a compact system, and fewer external leakage points compared to inline valves, which screw directly into a pipe port.

2. Installation & Operation

Q5: What are the key considerations when installing this valve?

A:​ The two most critical points are:

1. The manifold bore must strictly conform to the dimensions and tolerances specified in the ISO 7368 standard​ for a NG10, 2-way cartridge.

2. The external pilot drain port (port X) must be connected directly and freely to the tank​ with minimal back pressure (typically < 5 bar). High back pressure on this port can cause inaccurate pressure settings or valve malfunction.

Q6: How do I adjust the pressure setting of this valve?

A:

1. Remove the "K"-type protective cap from the end of the adjustment screw.

2. Use a suitable hex key to turn the adjustment screw.

3. Clockwise rotation increases pressure; counterclockwise rotation decreases pressure.

4. Adjust while the system is under load (with flow across the valve) and monitor a pressure gauge.

5. After adjustment, replace the protective cap.

Q7: Can it be used for remote pressure control or system unloading?

A:​ Yes. This is a core function of pilot-operated relief valves.

• Remote Pressure Control:​ Connect an external pressure relief or reducing valve to the remote control port (Y). The system pressure will then be determined by the lower setting of the two valves.

• System Unloading:​ Connect a directional control valve (e.g., a solenoid valve) between the remote control port (Y)​ and the tank. When the solenoid valve is energized, it vents the pilot pressure, causing the main valve to open fully and unload the system to tank at minimal pressure.

Q8: What is the function of the damping piston on the main poppet?

A:​ The damping piston helps to dampen oscillations and reduce noise​ (hiss or chatter) that can occur during operation, especially near the cracking pressure, resulting in more stable system performance.

3. Troubleshooting & Compatibility

Q9: The valve is noisy or shows pressure instability. What could be the cause?

A:​ Common reasons include:

• Excessive back pressure on the external drain (X) port.

• Contamination blocking the small orifices in the pilot stage or damping piston.

• Incorrect viscosity of the hydraulic fluid for the operating temperature.

• Air in the system.

Q10: What types of hydraulic fluid is this valve compatible with?

A:​ It is designed primarily for mineral-based hydraulic oils (HL, HLP per DIN 51524). The standard FKM (Viton) seals are also compatible with HFA and HFC fluid emulsions/solutions. For other fluids (e.g., bio-oils, phosphate esters), seal material compatibility (potentially requiring a different version) must be verified.

Q11: What happens if the pressure setting is adjusted beyond 315 bar?

A:​ The valve should not be adjusted above its nominal 315 bar rating. Doing so may compromise performance, accelerate wear, cause instability, and potentially lead to component failure, voiding warranties and creating a safety risk. Always operate within the specified maximum pressure.