R900423729 DBDS6P1X/200 Direct acting plug-in overflow valve from Rexroth, Germany

FAQ - Frequently Asked Questions

Q1: What is the difference between DBDS6P1X and DBDS6K1X?

A:​ The "P"​ in the model code indicates Subplate Mounting​ (ISO 4401 interface), while "K"​ indicates a Screw-in Cartridge​ design. The DBDS6P1X is a complete valve assembly with a body and ports, whereas the DBDS6K1X is a cartridge that inserts into a custom manifold block.

Q2: Can I adjust the pressure beyond 200 bar?

A:​ No.​ The "/200"​ suffix denotes the 200 bar pressure stage spring. Although the valve body can withstand up to 400 bar, the spring is calibrated for a maximum reliable setting of 200 bar. Attempting to exceed this will result in inaccurate pressure control and potential spring damage.

Q3: Is this valve suitable for water glycol (HFC) fluids?

A:​ Yes.​ The standard NBR seals used in this model are compatible with HFC water glycol fluids. However, for phosphate ester (HFD) fluids, a variant with FKM (Viton) seals (typically denoted by a /V​ suffix) is required.

Q4: Why is my valve leaking or not holding pressure?

A:​ Common causes include:

1. Contamination:​ Dirt or debris preventing the poppet from sealing. Ensure ISO 4406 20/18/15 cleanliness.

2. Damaged Seal:​ Check for worn or extruded NBR seals.

3. Over-tightening:​ Excessive torque on the adjustment mechanism can damage internal components.

Q5: What is the effect of backpressure at the T (tank) port?

A:​ Backpressure is fully additive.​ Any pressure at the T-port is added to the spring setting. For example, if the valve is set to 180 bar and the T-port has 20 bar of backpressure, the system will relieve at 200 bar. Ensure the total pressure does not exceed the valve's maximum rating.