Product Overview
The A6VM series bent-axis axial piston variable motors are a flagship product line within the Bosch Rexroth hydraulic transmission platform, classified as all-purpose high-pressure motors. Featuring a bent-axis design with axial tapered piston rotary groups, these motors are specifically engineered for hydrostatic drives in both open and closed circuits. Designed to fully comply with Rexroth A6VM Series 63 mounting and interface standards, these motors offer 100% direct interchangeability with original Rexroth units—enabling plug-and-play replacement without any管路 modifications or adapter plates, significantly minimizing downtime and retrofit costs.
The A6VM series covers a wide displacement range from 28 to 1000 cc/rev, supporting full-scenario applications. Through various variable control methods—electrical proportional, hydraulic proportional, and electrical/hydraulic two-point control—the displacement can be continuously adjusted from Vg max down to Vg min ≈ 0. Every unit undergoes 100% factory testing under simulated real-world working conditions, validating pressure, flow, volumetric efficiency, and control characteristics before shipment—ensuring reliable operation from the very first start.
Model Code Interpretation:
A6VM200EP2D/63W-VAB027OPB
A6VM – Series code: Bent-axis axial piston variable motor
200 – Displacement size: 200 cm³/rev
EP2D – Control type: Electric proportional control, dual coil, with suppressor diode
63 – Series number: Series 63
W – Rotation direction and port configuration
VAB027OPB – Specific configuration code (including flushing valve, boost-pressure valve options)
A6VM80DA/6.0W-0292
A6VM – Series code: Bent-axis axial piston variable motor
80 – Displacement size: 80 cm³/rev
DA – Control type: Hydraulic remote control (DA control)
6.0W – Specific design code and configuration
0292 – Product configuration code
Technical Specifications
A6VM200EP2D/63W-VAB027OPB
Model: A6VM200EP2D/63W-VAB027OPB
Type: Bent-axis axial piston variable motor (Series 63)
Displacement: 200 cm³/rev
Nominal Pressure: 400 bar
Maximum Pressure: 450 bar
Maximum Speed (at Vg max): 2800 r/min
Maximum Speed (at Vg < Vg max): 4350 r/min
Maximum Inlet Flow (at nmax): 560 L/min
Shaft Torque (Δp=400 bar): 1018 N·m
Control Type: EP2D – Electric proportional control, dual coil
Weight: Approx. 66 kg
Housing Material: High-strength cast iron
Medium: Mineral oil, synthetic hydraulic oil
Operating Temperature Range: -25℃ to +90℃
A6VM80DA/6.0W-0292
Model: A6VM80DA/6.0W-0292
Type: Bent-axis axial piston variable motor (Series 63)
Displacement: 80 cm³/rev
Nominal Pressure: 400 bar
Maximum Pressure: 450 bar
Maximum Speed (at Vg max): 3900 r/min
Maximum Speed (at Vg < Vg max): 6150 r/min
Maximum Speed (at Vg min): 7350 r/min
Maximum Inlet Flow (at nmax): 312 L/min
Shaft Torque (Δp=400 bar): 509 N·m
Control Type: DA – Hydraulic remote control
Weight: Approx. 36–39 kg
Housing Material: High-strength cast iron
Medium: Mineral oil, synthetic hydraulic oil
Operating Temperature Range: -25℃ to +90℃
A6VM Series General Parameters (Series 63) :
Displacement Range: 28–1000 cc/rev (28/55/80/107/140/160/200/250/355/500/1000)
Sizes 28–200: Nominal pressure 400 bar / Peak pressure 450 bar
Sizes 250–1000: Nominal pressure 350 bar / Peak pressure 400 bar
Circuits: Open and closed circuits
Mounting: SAE standard flange mounting
Key Technical Advantages
1. 100% Direct Interchangeability – Zero Modification Required
The A6VM series is engineered to exact Rexroth A6VM Series 63 mounting and interface specifications, with identical dimensions, port locations, and shaft end configurations. End users can replace original units directly without any管路 modifications or adapter plates—transforming unplanned downtime into scheduled, rapid maintenance while significantly reducing spare parts procurement costs and equipment downtime losses.
2. Bent-Axis Compact Design – High Power Density with Stepless Control
The bent-axis compact design and high-strength bearing system deliver high power density and low moment of inertia. Displacement can be steplessly adjusted from Vg max down to Vg min ≈ 0. By eliminating gear-shifting mechanisms, smaller pumps can be used to achieve a wide speed range, significantly reducing system cost and space requirements.
3. High-Speed Capability with Long-Life Bearing System
Approved for very high-speed operation. Equipped with a compact, robust long-life bearing system featuring an excellent power-to-weight ratio, superior starting characteristics, and low moment of inertia. Optimized hydraulic circuits and low-friction structures ensure high starting efficiency and smooth operation characteristics.
4. Multiple Control Options for Flexible Adaptation
The A6VM series offers a wide range of control options—EP2D electric proportional control (dual coil, with suppressor diode), DA hydraulic remote control, HA high-pressure related automatic control, HD hydraulic proportional control, HZ hydraulic two-point control, EZ electric two-point control, and more. The EP2D electric proportional control supports remote precision displacement adjustment with rapid response; DA control enables displacement adjustment via hydraulic remote signals, ideal for automatic speed matching in mobile machinery.
5. Modular Design with Flexible Function Expansion
Optional functional modules include flushing valves, boost-pressure valves, and bidirectional counterbalance valves. Modular components support rapid maintenance and upgrades, reducing energy consumption and maintenance costs.
6. 100% Factory Testing Under Simulated Working Conditions
Every A6VM series unit undergoes rigorous factory testing under simulated real-world conditions, validating pressure, flow, volumetric efficiency, control response characteristics, and thermal performance across the full operating range. Test media match actual operating conditions, ensuring each unit is ready for immediate installation and reliable operation upon delivery—eliminating the risk of “dead on arrival” components.
Application Areas
The A6VM series variable motors are widely deployed across the following industries and equipment types:
Construction Machinery: Excavator travel/swing drives, rotary drilling rig power heads
Road Construction Equipment: Roller travel drives, asphalt pavers
Crane Machinery: Crane hoisting mechanisms, swing mechanisms
Mining Equipment: Mining machinery, rock drilling rigs
Agricultural Machinery: Large tractors, combine harvesters
Marine & Shipbuilding: Marine winches, deck machinery
Industrial Equipment: Metallurgical equipment, injection molding machines
Specific model applications include:
A6VM200EP2D/63W-VAB027OPB: Rotary drilling rig power heads, large crane hoisting mechanisms
A6VM80DA/6.0W-0292: Medium excavator travel drives, compact loader equipment
Expert Maintenance Tips
1. Hydraulic Fluid Cleanliness Management
The A6VM series utilizes bent-axis axial piston designs with minimal clearances between pistons and cylinder bores, making them highly sensitive to fluid contamination. It is recommended to install filters with ≤10μm filtration rating, maintaining fluid cleanliness to ISO 4406 19/17/14 or better. Recommended oil viscosity is 16–36 mm²/s (at operating temperature). Never use degraded or substandard hydraulic fluids.
2. EP2D Electric Proportional Control Tuning (A6VM200EP2D)
The EP2D control is an electric proportional control, dual coil, with suppressor diode. Before wiring, verify that the control system output current range matches the coil specifications to avoid coil burnout from overcurrent or sluggish control response from insufficient current. The control signal is current-based; PWM regulation is recommended.
3. DA Hydraulic Remote Control Tuning (A6VM80DA)
The DA control is a hydraulic remote control type that adjusts displacement via external pilot oil pressure signals. During commissioning, verify that the pilot oil supply pressure is stable and cleanliness is adequate. DA control is suitable for automatic speed matching in mobile machinery—fine-tune the pilot pressure setting according to actual operating conditions.
4. Air Bleeding and Pre-filling Before Start-up
Always bleed air from the motor housing via the highest vent port before initial start-up or after extended shutdown periods to prevent cavitation damage. Ensure the motor housing is completely filled with hydraulic fluid prior to starting.
5. Coupling Alignment Requirements
Maintain shaft alignment within 0.05 mm concentricity and 0.5° angular deviation between the drive shaft and the load shaft. Excessive misalignment will lead to premature bearing wear and shaft seal leakage. The use of flexible couplings is recommended to compensate for minor installation deviations.
6. Case Drain and Backpressure Control
Ensure the case drain line is unrestricted with no flow restrictions. Excessive case backpressure will cause shaft seal damage and premature bearing failure. The drain line should return directly to the reservoir, not in parallel with the return line.
7. Periodic Inspection and Maintenance
Inspect shaft seals for leakage and listen for abnormal operating noise every 1,000 operating hours or every 6 months (whichever comes first). If reduced volumetric efficiency or insufficient output torque is observed, timely overhaul of the piston assembly and valve plate is recommended.
