Rexroth A6VM A6VE Series Control Valve | HA2T EP2D HD1D EZ | Hydraulic Motor Control

Chengyuan Hydraulic offers high-precision control valves for A6VM and A6VE series variable motors, specifically designed as high-quality replacements for Rexroth bent-axis motors. This lineup includes versatile control types such as HA2T, EP2D, HD1D, and EZ, which are mounted directly onto the motor end cover to manage stepless or two-position displacement adjustments. In demanding applications like travel drives or winching, precise torque and speed transitions are critical. Chengyuan ensures 100% Drop-in Interchangeability regarding mounting interfaces, feedback linkage positions, and electrical signals. Backed by our 100% Simulation Load Testing, every valve assembly is validated for response timing and start-of-control pressure before shipment, ensuring smooth acceleration and deceleration even under extreme load conditions.

Technical Specifications 

• Compatible Motor Series: A6VM (Standard) / A6VE (Plug-in)

• Applicable Sizes: 28, 55, 80, 107, 140, 160, 200, 250

• Control Type – EP2D/E: Proportional electric control, U=24V or 12V DC, load-independent regulation.

• Control Type – HD1D/E: Proportional hydraulic control based on pilot pressure signals.

• Control Type – HA2T/HA1R2: Automatic pressure-related control (No external signal required; displacement changes based on working pressure).

• Control Type – HZ/EZ: Two-position switching (Hydraulic or Electric).

• Max Control Pressure: 400 bar

• Max Ambient Temperature: Up to 110°C (depending on coil rating)

• Response Time: 50ms – 200ms (configurable via orifices)

Key Technical Advantages:

• Precision Compensation Mechanism: Internal feedback pistons and spring sets undergo rigorous fatigue testing, ensuring the start-of-control pressure drift remains within ±2% after thousands of cycles.

• Highly Integrated Internal Passages: The valve blocks are manufactured from high-grade ductile iron using 5-axis CNC centers. Internal flow surfaces feature a Ra 0.8 finish to minimize signal hysteresis and pressure loss.

• High-Temperature Resistant Solenoids: EP series proportional solenoids utilize Class F insulation and support 100% Continuous Duty Cycle (ED), making them suitable for high-heat environments like excavator engine compartments.

• Customizable Damping: Multiple orifice sizes are available to match specific machinery requirements, preventing hydraulic shocks during rapid displacement changes and protecting the entire drivetrain.

Application Areas:

• Travel Drives: Crawler drives for excavators and travel systems for wheel loaders.

• Lifting Mechanisms: Main winches for cranes and power-head drives for rotary drilling rigs.

• Specialty Vehicles: Drum drive controls for concrete mixer trucks.

Expert Maintenance Tips:

• Start-of-Control Calibration: When installing HA series (automatic) valves, if displacement switching occurs too early or late, use the external adjustment screw to fine-tune. Never adjust while the motor is at full speed.

• Seal Inspection: When replacing the valve group, always inspect the O-rings at the interface—especially the dynamic seal at the displacement feedback rod. Any wear here will result in insufficient signal pressure.

• Electrical Protection: For electric models (EP/EZ), ensure that connectors meet the required ingress protection (IP) rating to prevent moisture from causing solenoid shorts or sluggish responses.