4WRZ16E3-100-7X/6EG24N9K4/M 4WRZ16E1-150-7X/6EG24N9TK4/D3M 4WRZ16E3-150-7X/6EG24N9K4/M Hydraulic Valves

For applications with frequent actuator cycling (e.g., injection molding, automated assembly), optimize energy use through these adjustments:

• Flow Calibration: Match the valve's maximum flow output to the actuator's actual speed requirement. For example, if an actuator only needs 120 L/min, reduce the control signal's upper limit from 800mA to 640mA (linear characteristic) to avoid unnecessary pump load.
• Pressure Compensation Fine-Tuning: Adjust the pressure compensator's bias spring (via the adjustment screw on the valve body) to minimize the pressure differential across the spool (typically 5-8 bar, instead of the default 10 bar) while maintaining flow stability. This reduces energy loss from throttling.
• Neutral Position Optimization: Ensure the valve returns to a true neutral position when the control signal is 0mA, eliminating parasitic flow that wastes pump power. Use a flow meter at the T port to verify no flow during standby.
• Load-Sensing Integration: If the system uses a load-sensing pump, connect the valve's load pressure feedback signal (from TK4 feature) to the pump controller. This allows the pump to only supply the pressure required by the load, rather than maintaining maximum pressure constantly.

For operation in environments below -20 °C or above 80°C, take these specialized measures:

Critical Note: Standard NBR seals (N9) are not suitable for temperatures below -20 °C or above 100°C. Contact Rexroth for FKM (Viton) seal upgrades for extreme conditions.

• Low-Temperature (-20 °C to -40°C): Use low-viscosity hydraulic oil (ISO VG 22) with pour point ≤-45°C to prevent fluid thickening and spool sticking.
• Install a pre-heater in the oil tank to raise the fluid temperature to ≥-10°C before activating the valve.
• Insulate the valve and adjacent pipelines to avoid heat loss; use heat-traced cables if necessary.

High-Temperature (80 °C to 120°C): Upgrade to synthetic hydraulic oil (e.g., polyalphaolefin) with high thermal stability to resist oxidation and viscosity breakdown.

Install a cooler in the return line to maintain fluid temperature below 80 °C; monitor temperature with a inline sensor linked to an alarm.

Use heat shields to protect the valve from direct radiation from high-temperature components (e.g., furnaces, exhaust pipes).