A10VSO piston pump

The A10VSO piston pump is a swashplate-type variable displacement axial piston pump manufactured by Bosch Rexroth, primarily used for hydrostatic transmission in open circuits.

First, Structural Principle

It employs a swashplate structure, achieving oil suction and discharge through the reciprocating motion of pistons within the cylinder block. The swashplate's tilt angle is adjustable, thereby altering the piston stroke to enable stepless flow variation.

Second, Technical Features

1. High Pressure: Nominal pressure typically reaches 280 bar, with peak pressure up to 350 bar, meeting diverse high-pressure operational demands.

2. High Efficiency: Features high overall and initial efficiency. Fluid static unloading of the rocker arm bearings minimizes energy loss.

3. Low Noise: Optimized design ensures low operational noise levels and minimal low-pressure pulsation, providing enhanced comfort in the work environment.

4. Rapid Response: Short control response time enables swift adjustment of flow and pressure according to system demands.

5. Superior Suction Performance: Excellent suction characteristics with high cavitation resistance effectively prevent failures caused by sudden drops in suction pressure or peak casing pressure.

Third, Core Advantages of the A10VSO Piston Pump

1. High Pressure, High Flow + High Efficiency: Nominal pressure 280 bar, peak pressure 350 bar, suitable for heavy-duty applications; fluid static unloading design (rocker arm/sliding shoe/plunger pair) ensures high mechanical/volumetric efficiency, low energy consumption, and excellent long-term operational economy.

2. Stepless Flow Regulation with Rapid Response: Variable displacement (0 to rated volume) achieved through swashplate tilt angle adjustment. Integrated with DR/DFR/DFLR control modules, it delivers swift closed-loop response for pressure/flow/power regulation, meeting dynamic load and precision speed control requirements.

3. Low noise, cavitation resistance, and reliable operation: Optimized unloading grooves and suction passages in the distributor suppress oil trapping and cavitation. Precision machining and premium materials ensure impact load tolerance and extended service life. Low pressure pulsation minimizes operational noise.

4. Highly modular and adaptable: Multiple displacements (18/28/45/71/100/140, etc.), control modes, and mounting/sealing/interface options enable customized configurations for open-loop systems in construction machinery, injection molding, metallurgy, marine applications, and more.

5. Excellent maintainability: Standardized spare parts, established maintenance systems, easy disassembly for inspection, and straightforward fault diagnosis.

Fourth, Core Drawbacks

1. High Cost with Significant Procurement and Maintenance Barriers: German-made imports incur high initial purchase costs; precision hydraulic components require specialized personnel and tools for repairs, with spare parts commanding premium prices.

2. Stringent Requirements for Fluid and Contamination Control: High-precision friction pairs (shoe-swashplate, distributor-cylinder block, etc.) are sensitive to fluid cleanliness (recommended NAS 7 or higher), viscosity, and temperature. Contaminated oil, abnormal temperatures, or improper viscosity readily cause wear, stalling, efficiency drops, or even pump failure.

3. Limited performance during startup and low-speed operation: High oil viscosity at low temperatures increases startup torque; at extremely low speeds, distribution and lubrication efficiency decline, potentially causing pressure pulsations and increased noise. Not suitable for prolonged ultra-low-speed operation.

4. Complex variable mechanism tuning: Parameter tuning for closed-loop control (e.g., DFLR power control) requires specialized expertise. Improper tuning may cause abnormal system response, increased energy consumption, and intensified shock loads.

5. Not suitable for closed circuits (inherent design limitation): The A10VSO is a dedicated open-circuit pump. For closed-circuit applications, auxiliary systems such as makeup oil pumps and flushing valves must be added, increasing system complexity and cost.

Rexroth A10VSO pump

Bosch axial piston variable pump