Product Overview
The A6VM107HD1/63W-VSD52000B is a mid-large displacement bent-axis axial piston variable motor from the Bosch Rexroth A6VM series, Series 63 frame size. The motor employs an axial tapered piston rotary group of bent-axis design, suitable for hydrostatic drives in both open and closed circuits. The motor offers a maximum displacement of 107 cm³/rev, nominal pressure of 400 bar, peak pressure of 450 bar, continuous torque of 681 N·m at nominal pressure, maximum speed of 3550 rpm at Vg max, maximum inlet flow of 380 L/min, and weight of approximately 47 kg.
The model code decodes as: “A6VM107” = A6VM series 107 displacement size, “HD1” = hydraulic pilot proportional control, “63W” = Series 63 with FKM fluoroelastomer seals, “VSD52000B” = mounting flange, shaft, and port configuration code. This model is an SAE version tailored for the US market.
The A6VM series is characterized by infinitely variable displacement from Vg max to Vg min = 0 — the wide control range enables the variable motor to satisfy the requirement for high speed and high torque. Output speed depends on pump flow and motor displacement, and output torque increases with the pressure differential between high-pressure and low-pressure sides and with increasing displacement. Cost savings are achieved through the elimination of gear shifts and the possibility of using smaller pumps. The motor features a compact, robust bearing system, high power density, good starting characteristics, and small swing torque.
The A6VM series offers a wide selection of control devices, including HD hydraulic pilot control, HA automatic high-pressure related control, and EP electro-hydraulic proportional control. With HD1 control, the motor displacement is infinitely varied in proportion to the hydraulic pilot signal at port X, with a control pressure increase of Δp = 10 bar achieving displacement regulation from Vmax to Vmin. The motor can also be equipped with optional integrated or attached flushing and boost pressure valves, helping maintain motor performance and extend service life by preventing contamination and facilitating cooling processes.
The motor offers complete interchangeability: mounting flange (ISO 3019-2 4-hole), splined shaft (DIN 5480 standard), and port configuration (SAE flange, opposite sides) are identical to the original Rexroth specification, with perfect interchangeability with equivalent products from Rexroth, Eaton, Parker, Kawasaki, Sauer-Danfoss, Komatsu, and more. Every unit undergoes 100% simulated duty-cycle testing before shipment.
Series Model Note: The A6VM series covers A6VM55, A6VM80, A6VM107, A6VM140, A6VM160, A6VM200, A6VM250, and other displacement sizes, along with A6VE plug-in variable motor variants. Sizes 28–200 have nominal pressure of 400 bar / peak 450 bar; sizes 250–1000 have nominal pressure of 350 bar / peak 400 bar.
Technical Specifications
A6VM107HD1/63W-VSD52000B (Primary Model)
Model: A6VM107HD1/63W-VSD52000B
Brand Series: Bosch Rexroth A6VM Series / Series 63
Motor Type: Bent-axis axial piston variable motor, axial tapered piston rotary group
Maximum Displacement Vg max: 107 cm³/rev
Minimum Displacement Vg min: 0 cm³/rev (adjustable to zero)
Nominal Pressure pN: 400 bar (40 MPa)
Peak Pressure pmax: 450 bar (45 MPa)
Maximum Speed (at Vg max): 3550 rpm
Maximum Speed (at Vg < Vg max): 5600 rpm
Maximum Inlet Flow: 380 L/min
Output Torque (Δp = 400 bar): 681 N·m
Specific Torque: 1.7 N·m/bar
Control Type: HD1 hydraulic pilot proportional control
Control Pressure Increase: Δp = 10 bar (port X, Vmax to Vmin)
Displacement Adjustment Range: Vg max to Vg min = 0
Seal Material: FKM (Fluoroelastomer)
Shaft Type: Splined shaft (DIN 5480 standard)
Mounting Flange: ISO 3019-2 4-hole
Port Connections: SAE flange, opposite sides
Rotation: Alternating reversible
Circuit Compatibility: Open/closed circuit universal
Weight: Approximately 47 kg
Optional Accessories: Flushing valve, boost pressure valve, counterbalance valve
A6VM Series Other Displacement Sizes (Series Reference)
A6VM55: Max displacement 54.8 cm³/r, nominal pressure 400 bar, peak pressure 450 bar, max speed 4450 rpm (Vg max), torque 349 N·m, weight approx. 26 kg
A6VM80: Max displacement 80 cm³/r, nominal pressure 400 bar, peak pressure 450 bar, max speed 3900 rpm (Vg max), torque 509 N·m, weight approx. 34 kg
A6VM107: Max displacement 107 cm³/r, nominal pressure 400 bar, peak pressure 450 bar, max speed 3550 rpm (Vg max), torque 681 N·m, weight approx. 47 kg
A6VM140: Max displacement 140 cm³/r, nominal pressure 400 bar, peak pressure 450 bar, max speed 3250 rpm (Vg max), torque 891 N·m, weight approx. 60 kg
A6VM160: Max displacement 160 cm³/r, nominal pressure 400 bar, peak pressure 450 bar, max speed 3100 rpm (Vg max), torque 1019 N·m, weight approx. 64 kg
A6VM200: Max displacement 200 cm³/r, nominal pressure 400 bar, peak pressure 450 bar, max speed 2900 rpm (Vg max), torque 1273 N·m, weight approx. 80 kg
A6VM250: Max displacement 250 cm³/r, nominal pressure 350 bar, peak pressure 400 bar, max speed 2700 rpm (Vg max), torque 1391 N·m, weight approx. 90 kg
HD Control Method Reference
HD1: Hydraulic pilot proportional control, control pressure increase Δp = 10 bar
HD2: Hydraulic pilot proportional control, control pressure increase Δp = 25 bar
HD3: Hydraulic pilot proportional control, control pressure increase Δp = 25 bar
HZ: Hydraulic two-position control
HA: Automatic high-pressure related control (without increment)
EP: Electro-hydraulic proportional control
EZ: Electric two-position control
Key Technical Advantages
① Bent-Axis Axial Tapered Piston Rotary Group — High Power Density and High Efficiency
The A6VM107 employs a bent-axis design with an axial tapered piston rotary group, in which pistons are arranged at an angle to the drive shaft, directly transferring pressure into torque. Compared to swash-plate designs, the bent-axis architecture achieves higher power density and more compact axial dimensions at equivalent displacement. The precision-lapped piston-to-bore surfaces maintain low internal leakage under high pressure. For space-constrained heavy-duty applications (mobile machinery travel drives, compact industrial transmission units), this design minimizes installation volume while maintaining high torque output.
② Displacement Adjustable to Zero — Wide-Range Stepless Speed Control
The A6VM107‘s displacement can be infinitely changed from Vg max to Vg min = 0. This characteristic enables smooth transitions between maximum displacement (maximum torque, minimum speed) and zero displacement (no output), achieving true stepless speed control without altering pump displacement. In travel drive applications, this enables full-range drive from low-speed high-torque climbing to high-speed low-torque flat travel without gearboxes, while reducing system cost and complexity through the elimination of gear shifts.
③ HD1 Hydraulic Pilot Proportional Control — Precise Control with Flexible Adjustment
With HD1 control, the motor displacement is infinitely varied in proportion to the hydraulic pilot signal at port X, with a control pressure increase of Δp = 10 bar achieving displacement regulation from Vmax to Vmin. The motor is normally at maximum displacement (maximum torque, minimum speed) and adjusts toward minimum displacement as pilot pressure increases. HD1 control can also be used for two-point or two-speed control by applying an on/off pilot signal to port X. Users can select from HD1, HD2, HD3, HA, EP, and other control methods based on application requirements.
④ Compact, Robust Bearing System with Long Service Life
The A6VM series features a compact, robust bearing system with long service life. Output bearings accommodate radial and axial combined loads, adapting to belt, chain, or gear drive applications with radial loading. Optional integrated or attached flushing and boost pressure valves help maintain motor performance and extend service life by preventing contamination and facilitating cooling processes. An optional integrated counterbalance valve provides additional safety and control by maintaining steady operation under variable loads.
⑤ Broad Interchange Compatibility and Modular Control Options
The A6VM107’s standardized mounting interfaces allow perfect interchangeability with equivalent products from Rexroth, Eaton, Parker, Kawasaki, Sauer-Danfoss, Komatsu, and more. The A6VM series offers a wide selection of control devices, including HD (hydraulic pilot control), HA (automatic high-pressure related control), and EP (electro-hydraulic proportional control), enabling users to select the most suitable control method for specific application requirements. Standardized interface design maintains mounting compatibility across different displacement sizes within the same series, facilitating equipment upgrades or displacement adjustments.
Application Areas
Mobile Machinery (Primary Application): Excavator travel drives, wheel loaders, rollers, pavers, concrete mixer trucks
Lifting & Winch Equipment: Crane hoist mechanisms, winch drives
Industrial Heavy-Duty: Metallurgical rolling mill auxiliary drives, mining drill rigs, belt conveyors
Marine: Deck machinery, winches, windlasses
Agricultural Machinery: Combine harvesters, cotton picker drive systems
Others: Open or closed hydraulic transmission systems requiring high pressure, wide speed range, and stepless variable displacement output
Expert Maintenance Tips
Pre-Installation Inspection: Verify flatness and cleanliness of the ISO 3019-2 4-hole mounting flange mating surface; check thread condition of mounting bolt holes. The splined shaft (DIN 5480) to coupling or drive-wheel fit must conform to standards, avoiding interference fits that could damage the spline. FKM seal lips must not be scratched or deformed. Use bolts of strength class 8.8 or higher, tightened in diagonal sequence to specified torque.
Casing Oil Filling and Drain Line: The casing must be filled with clean hydraulic oil before initial start-up. Fill through the highest casing port until oil overflows from the level port. Rexroth officially requires that “the motor housing must be filled with hydraulic oil during startup and operation.” The drain line arrangement must ensure the motor housing does not self-drain when the motor is stationary, with the pipe end submerged below the minimum oil level in the tank. Case drain pressure should be kept as low as possible to extend shaft seal life.
Fluid Cleanliness and Temperature Control: Maintain system oil cleanliness at NAS 8 (ISO 4406 18/16/13) or better. The precision-matched valve plate and piston pairs are sensitive to particulate contamination; excessive contamination accelerates wear and causes volumetric efficiency degradation. Oil viscosity should remain within the optimum range at operating temperature, with higher viscosity classes recommended. The A6VM motor is not suitable for operation with HFA hydraulic fluid; if HFB, HFC, HFD, or environmentally acceptable fluids are used, limitations regarding technical data or other seals must be observed.
Scheduled Inspection: Check casing drain flow and output shaft spline wear every 500 operating hours. Under normal conditions, drain flow should remain stable; a sustained increase indicates accelerated wear of piston pairs or valve plate surfaces, and preventive maintenance should be scheduled. Also inspect HD1 controller response linearity; if displacement regulation exhibits lag or non-linearity, inspect pilot control pressure (port X, Δp = 10 bar) and flushing valve operation.
Long-Term Storage Protection: If the motor will be idle for more than 3 months, fill the casing with rust-preventive hydraulic oil and manually rotate the shaft several turns monthly to prevent corrosion or adhesion on piston pairs and valve plate surfaces. Perform a no-load run-in before returning to service.
