Rexroth AA6VLM axial piston variable hydraulic motor

Unlike swashplate designs, the AA6VLM uses a bent-axis principle. The cylinder block is angled relative the drive shaft—typically between 7° and 40°. This angle allows the pistons to stroke naturally without side forces, dramatically increasing bearing life and enabling higher torque densities.

Performance Characteristics That Drive Productivity

1.Superior Start-Up Torque & Low-Speed Behavior

Many piston motors struggle with “stick-slip” at crawl speeds. The AA6VLM’s precision-machined piston slippers and hardened cylinder bore coating allow smooth rotation below 10 RPM without external case flushing—provided you maintain oil cleanliness (ISO 4406 18/16/13 minimum).

2.High-Speed Capability with Variable Displacement

At minimum displacement (approx. 30% of max), the same motor can spin up to 3,600 RPM. This dual personality replaces a two-speed gearbox in many designs.

3.Robust Hydrostatic Braking & Overrun Protection

When used as a secondary or service brake, the AA6VLM becomes a hydrostatic absorber. By closing the outlet port or applying negative displacement, the motor generates braking torque proportional to pressure. The integrated shuttle valve and boost ports prevent cavitation during overrun.

Where to Deploy the AA6VLM – Real-World Use Cases

Mobile Equipment

Wheel loaders – Propel drive with traction control via displacement sensing.

Self-propelled forage harvesters – Header drive requiring variable speed without a CVT.

Drilling rigs – Rotary table drive where torque must adapt to rock density.

Industrial & Marine

Continuous miners – Cutting head drive with shock load damping.

Winch drives – Tension-controlled mooring winches on offshore vessels.

Sizing & Control Strategies – Avoid Common Mistakes

Selecting the wrong displacement range or control type is expensive. Follow this hierarchy:

1.Determine peak torque – Multiply max pressure (bar) × displacement (m³/rev) ÷ 20π.

2.Match control to duty cycle – Use hydraulic pilot (HD) for simple on/off; use electric proportional (EP) for closed-loop speed control.

3.Never overspeed – Exceeding max rated RPM at minimum displacement destroys the retainer plate.

Control Examples

DA control – Speed-sensitive (auto displacement change with input flow).

EZ control – Electric 2-point (high/low displacement with a solenoid).

HD control – Hydraulic remote proportional (smooth, analog).

Maintenance & Life Extension

The AA6VLM is a precision instrument, not a fixed gear motor. Extend its life by monitoring:

Case drain flow – Should be <10% of input flow. Higher indicates piston or slipper wear.

Shaft radial load – Maximum allowable radial force is listed in the data sheet (often 4,000–8,000 N depending on frame size). Exceeding it bends the shaft and kills the tapered roller bearings.

Flushing interval – First oil change at 100 hours; then every 1,000 hours or annually.

For more information on the AA6VLM hydraulic motor, please visit https://www.baolilaihydraulic.com/product/.

Specifications

Selection Table

Q1: What is the difference between AA6VLM and A6VM?

A1:The “L” signifies a larger, more robust bearing arrangement for higher radial loads. The A6VM is the standard industrial version; the AA6VLM is for mobile/marine with heavier-duty shaft seals.

Q2: Why does my motor case pressure spike when I reduce displacement quickly?

A2:That’s displacement-induced cavitation. Install a case accumulator or slow down the control signal ramp time (e.g., use a 0.5s throttle in the pilot line).

Q3: What is the price and delivery time of the AA6VLM hydraulic motor?

A3: The specific price and delivery time will be provided based on the specific model you provide.

Q4:How to purchase an AA6VLM hydraulic motor?

A4:You can visit https://www.baolilaihydraulic.com/contact/ to contact us and purchase our products through various methods.