R983030774 4WMM10J3X/F Rexroth manual valve made in Germany

FAQ - Frequently Asked Questions

Q1: What does the "/F" suffix mean in the model number?

A:​ The /F​ suffix indicates that the valve is equipped with a detent mechanism (ball-and-spring). This allows the lever to be locked into any of its three positions (Left, Center, Right). When you release the lever, it stays in that position. This is different from the spring-centered version (without /F), which automatically returns to center when released.

Q2: What is the "J" spool function?

A:​ The "J" spool​ has a specific center position flow path: P (Pressure) is blocked, and A & B (work ports) are connected to T (Tank). This configuration allows the connected actuator (cylinder or motor) to float freely​ when the valve is in the center position, as both sides are unloaded to the tank. It is commonly used in applications like crane hooks or free-wheeling circuits.

Q3: What is the maximum flow rate for this NG10 valve?

A:​ The comfortable operating flow is 120 L/min. While it can handle peaks up to 160 L/min, doing so will result in high pressure drops and may require excessive force to shift the lever. For systems consistently above 120 L/min, consider upgrading to an NG16 size valve.

Q4: Can this valve be used with water glycol (HFC) or phosphate ester (HFD) fluids?

A:​ Yes for HFC, No for HFD with standard seals.​ The standard NBR seals are compatible with Water Glycol (HFC). However, if you are using Phosphate Ester (HFD)​ fluids, you must order a variant with FKM (Viton®) seals, which typically have a /V​ suffix (e.g., 4WMM10J3X/F/V).

Q5: What is the difference between the "3X" and "5X" series?

A:​ The 3X​ (30-series) and 5X​ (50-series) refer to different design generations. The external mounting dimensions (ISO 4401 NG10) are fully interchangeable. The main differences are internal (spool tolerances, leakage rates). Always confirm spool function compatibility if replacing an existing valve