Rexroth piston pump A10VSO28DFR/31R-PPA12N00

1. Model Interpretation

• A10VSO: Series identifier, representing variable displacement axial piston pump with swashplate design for open-circuit hydrostatic drives, which is widely used in industrial hydraulic systems.
• 28: Nominal size, indicating the maximum geometric displacement per revolution is 28 cm³superscript:3″>.
• DFR: Control mode, standing for pressure and flow controller (DFR) without a small hole in the X oil circuit, realizing automatic flow adjustment through pressure feedback.
• 31R: Mounting and rotation direction, 31 represents the 3rd generation and 1st version series specification, and R indicates clockwise rotation when viewed from the shaft end.
• PPA12N00: Control accessories; P stands for FKM shaft seal and keyed straight shaft (DIN 6885), A refers to ISO 2-hole mounting flange, 12 indicates that the pressure port B and suction port S are in opposite directions with SAE metric fixed screws; N00 indicates no through drive and no additional special configuration.

2. Basic Information

• Product Brand: Rexroth (Bosch Rexroth AG)
• Pump Type: Variable displacement axial piston pump
• Operating Circuit: Open circuit
• Structural Design: Swashplate design, with precision plunger and barrel assembly.
• Material: Cast iron (main body)
• Common Material Number: Reference only, subject to actual delivery

3. Key Technical Parameters

3.1 Displacement

• Maximum Geometric Displacement per Revolution: 28 cm³/rev
• Minimum Displacement: 0 cm³/rev (stepless adjustable by swashplate, with adjustment range of 0-100%)

3.2 Pressure Parameters

• Nominal Pressure (pₙₒₘ): 280 bar (long-term stable working pressure)
• Maximum Pressure (pₘₐₓ): 350 bar (peak pressure, single operating duration shall not exceed 5 seconds, total operating duration shall not exceed 300 hours)
• Minimum Outlet Pressure: 10 bar (to prevent damage to the axial piston unit)
• Inlet Pressure (absolute): Minimum 0.8 bar (0.5 bar for cold start), Maximum 10 bar
• Maximum Case Drain Pressure: 2 bar (absolute), shall not exceed 0.5 bar higher than the inlet pressure at port S)
• Pressure Change Rate (RA): 16000 bar/s

3.3 Rotational Speed

• Maximum Rotational Speed at Maximum Displacement (nₙₒₘ): 2800 rpm
• Maximum Permissible Rotational Speed at Displacement < Maximum Displacement: 3000 rpm
• Standard Operating Rotational Speed: 1800 rpm (long-term continuous working speed)

3.4 Flow Rate

• Maximum Flow Rate at Nominal Speed (2800 rpm) and Maximum Displacement: 78 L/min (theoretical flow, affected by pressure, oil temperature and viscosity in actual operation)
• Flow Rate at 1800 rpm and Maximum Displacement: 50 L/min
• Minimum Flow Rate: 0 L/min (stepless adjustable)

3.5 Power and Torque

• Maximum Power at Nominal Pressure (280 bar), Nominal Speed (2800 rpm) and Maximum Displacement: 36 kW
• Power at Nominal Pressure (280 bar), 1800 rpm and Maximum Displacement: 23 kW
• Maximum Torque at Maximum Displacement and Nominal Pressure: 124 Nm

3.6 Oil Requirements

• Recommended Oil Type: Mineral oil, hydraulic fluid HF; synthetic hydraulic oil or biodegradable hydraulic oil are also applicable
• Operating Temperature Range: -20℃ to +80℃ (ambient temperature), up to +100℃ for short time
• Oil Viscosity: 10 – 1000 mm²/s (operating viscosity), 32 – 68 mm²/s (optimal viscosity)

4. Installation and Connection Parameters

• Mounting Flange: ISO 3019-2 (metric), 2-bolt (ISO 2-hole)
• Shaft End: ISO key mounting (keyed straight shaft, DIN 6885)
• Service Line Connections: B flange (metric), S flange (metric); pressure port B and suction port S are in opposite directions with SAE metric fixed screws
• Drain Ports: 2 drain ports, the internal leakage oil must be discharged to the oil tank through the highest drain port of the housing
• Through Drive: Without through drive
• Connector for Solenoids: Without

5. Physical Parameters

• Sealing Material: FKM (standard), with NBR seal conforming to DIN ISO 1629
• Weight (approx.): 22 kg
• Paint/Coating: Without paint/top coat

6. Product Characteristics

• Low operating noise and long service life, with high precision plunger pair ensuring good wear resistance
• Controls with short response times and excellent suction characteristics, suitable for various working conditions
• Stepless flow adjustment by swashplate adjustment, with adjustable range of 0-100%
• Compact structure and high power-weight ratio, suitable for engineering machinery, industrial hydraulic stations and other medium-pressure application fields
• The drive shaft can bear axial and radial loads, and the flange connection conforms to SAE metric standard

Note