A10VSO71DFR/31R-PSC12N00 Rexroth Axial Piston Pump 280 Bar

Product Overview

The A10VSO71DFR/31R-PSC12N00 belongs to the Bosch Rexroth A10VSO Series 31 open-circuit swashplate axial piston variable displacement pump family, with a displacement of 71 cc/rev (4.33 in³/rev), DFR pressure and flow control, and right-hand rotation. It delivers a nominal working pressure of 280 bar (4060 psi), maximum pressure of 350 bar (5100 psi), and a theoretical maximum flow of 156 L/min at 2200 rpm.

The A10VSO45DFLR/31R-PPA12N00 is the 45 cc/rev displacement variant in the same series, featuring DFLR pressure, flow, and power compound control, also configured for right-hand rotation, with nominal pressure of 280 bar and maximum pressure of 350 bar. This pump achieves a maximum speed of 2600 rpm at the 45 cm³ displacement class, with a theoretical flow of 117 L/min.

The A10VSO Series 31 covers displacements from 18 to 140 cc/rev (A10VSO18/28/45/71/88/100/140), featuring a swashplate variable displacement design where flow is proportional to drive speed and displacement, infinitely variable by adjusting the swashplate angle. The pump features two drain ports, excellent suction performance, low noise level, long service life, and a favorable power-to-weight ratio. The through-drive is suitable for adding gear pumps and axial piston pumps up to the same size, i.e., 100% through-drive.

Every pump undergoes 100% simulated operating-condition testing before shipment, including rated pressure hold, flow characteristic verification, and control response validation—delivering immediate reliability upon installation. The product meets ISO 4406 cleanliness requirements.

Technical Specifications

Model Identification:

• A10VSO71DFR/31R-PSC12N00 — 71 cc/rev, DFR pressure and flow control, right-hand rotation, SAE 2-bolt flange

• A10VSO45DFLR/31R-PPA12N00 — 45 cc/rev, DFLR pressure, flow and power control, right-hand rotation, SAE 2-bolt flange

• Model code breakdown (A10VSO71DFR/31R-PSC12N00): A10VS=swashplate variable pump (industrial drive), O=open circuit, 71=displacement size, DFR=pressure and flow control, 31=Series 31, R=right-hand (clockwise), P=NBR seals, SC=splined drive shaft, 12=port specification, N00=without through-drive

Displacement (A10VSO Series 31):

• A10VSO18: 18 cc/rev

• A10VSO28: 28 cc/rev

• A10VSO45: 45 cc/rev

• A10VSO71: 71 cc/rev

• A10VSO88: 88 cc/rev

• A10VSO100: 100 cc/rev

• A10VSO140: 140 cc/rev

Pressure Ratings (Full Series 31):

• Nominal pressure: 280 bar (4060 psi)

• Maximum pressure: 350 bar (5100 psi)

• Maximum case drain pressure: not exceeding 2 bar absolute (not exceeding 0.5 bar above suction port pressure)

Speed Range:

• A10VSO28: min. 600 rpm, max. 3000 rpm

• A10VSO45: min. 600 rpm, max. 2600 rpm

• A10VSO71: min. 600 rpm, max. 2200 rpm

• A10VSO100: min. 600 rpm, max. 2000 rpm

• A10VSO140: min. 600 rpm, max. 1800 rpm

Theoretical Flow (at rated speed):

• A10VSO45: 117 L/min at 2600 rpm

• A10VSO71: 156 L/min at 2200 rpm

• A10VSO100: 200 L/min at 2000 rpm

• A10VSO140: 252 L/min at 1800 rpm

Control Types:

• DFR / DFR1 — Pressure and flow compound control: combines pressure compensation with load-sensing flow regulation; DFR1 has X-T port closed (no flushing function), fast response, ideal for systems requiring high flow control precision

• DFLR — Pressure, flow and power compound control: adds power limiting function on top of DFR, enabling constant power control by automatically reducing displacement as system pressure rises

• Optional controls: DG two-point direct control, DR pressure control, DRG remote pressure control, ED electro-hydraulic pressure control, ER electro-proportional control, etc.

Structural Parameters:

• Pump type: Open-circuit swashplate axial piston variable displacement

• Mounting flange: SAE 2-bolt or ISO 4-bolt (model-dependent)

• Drive shaft: Splined or keyed

• Rotation: Right-hand (clockwise), viewed from shaft end

• Port connections: SAE flange per SAE J518C

• Seal material: NBR (nitrile rubber)

• Through-drive: Supported (100% through-drive), suitable for gear pumps and axial piston pumps up to the same size

• Weight: A10VSO71 approx. 33 kg; A10VSO45 approx. 21 kg

• Housing material: Cast iron

• Mounting position: Optional, any position

Hydraulic Fluid and Operating Conditions:

• Recommended fluid: Mineral oil (HL, HLP) per DIN 51524

• Optimal viscosity range: 15-100 cSt

• Operating oil temperature range: -20°C to +90°C

• Cleanliness requirement: ISO 4406 18/16/13 or better

Key Technical Advantages

1. Complete Model Coding Enables 100% Drop-in Interchange

The A10VSO Series 31 employs a standardized model code system: each character in the A10VSO71DFR/31R-PSC12N00 corresponds to specific parameters—displacement class (71), control type (DFR), series designation (31), rotation direction (R=right-hand), seal material (P=NBR), drive shaft type (SC=splined shaft), port specification (12), and through-drive option (N00=without through-drive). The SAE 2-bolt mounting flange, splined drive shaft, and SAE flange ports are identical to the original Rexroth pump, enabling direct bolt-on replacement without piping modification or adapter plates.

2. DFR Pressure-Flow Compound Control Optimizes System Efficiency

DFR control integrates pressure compensation with load-sensing flow regulation. When actuators stop, the pump automatically reduces displacement to near zero, maintaining only the minimum pressure required for control—significantly reducing system heat generation and energy loss. The closed X-T port design of the DFR1 variant eliminates flushing circuit leakage, making it ideal for industrial hydraulic systems requiring high flow control precision. Control response is fast, with a standard pilot valve differential pressure setting of 20 bar (290 psi).

3. DFLR Constant Power Control Achieves Optimal Energy Matching

The DFLR control on the A10VSO45DFLR/31R-PPA12N00 adds power limiting to the DFR function. Through a hyperbolic power regulation mechanism, the pump automatically reduces displacement as system pressure rises, keeping the pump’s input power within the set value. This control is particularly suited for mobile hydraulic systems with limited prime mover power, enabling optimal utilization of engine power.

4. Excellent Suction Performance and Low Noise Design

The A10VSO series features an optimized port plate design and swashplate rotary group structure, delivering excellent suction performance and low operating noise. Flow rate is proportional to drive speed and displacement, providing stable and predictable output. The pump features 2 drain ports for convenient installation and routing.

5. 100% Through-Drive Supports Multi-Pump Tandem Configuration

The A10VSO series supports 100% through-drive, enabling tandem installation of gear pumps and axial piston pumps up to the same size behind the primary pump. This enables single power source operation of multi-circuit hydraulic systems. The compact cast iron housing achieves high power density within constrained installation spaces, with a favorable power-to-weight ratio suitable for the tight layouts of mobile machinery and industrial hydraulic systems.

Application Areas

• Injection molding machines and die-casting machine hydraulic power systems

• Machine tool hydraulic systems (bending machines, presses, shears)

• Construction machinery (excavators, loaders, cranes) hydraulic systems

• Agricultural machinery (tractors, combine harvesters) hydraulic drive systems

• Metallurgical equipment and forging machinery hydraulic power units

• Marine deck machinery and port equipment hydraulic drive systems

• Industrial hydraulic power units and hydraulic test benches

• Wind turbine hydraulic pitch control systems

Expert Maintenance Tips

1. Pre-Installation Model Verification

Verify the complete model code on the pump nameplate before installation. The A10VSO71DFR/31R-PSC12N00 is configured for right-hand rotation (R code), with a splined drive shaft (SC code) and NBR seals (P code). The A10VSO45DFLR/31R-PPA12N00 has a keyed drive shaft (PP code). Ensure drive shaft-to-coupling concentricity within 0.05 mm to prevent premature seal failure from radial loads.

2. Hydraulic Fluid and Cleanliness Requirements

Use HLP mineral oil-based anti-wear hydraulic oil conforming to DIN 51524. Optimal operating viscosity range: 15-100 cSt. Fluid cleanliness should be ISO 4406 18/16/13 or better. Suction filter rating should be no coarser than 10 μm. Operating oil temperature range: -20°C to +90°C, with optimal operating temperature of 30-70°C. Flush the system thoroughly before first operation.

3. Case Drain Line Installation

Provide a properly sized case drain line. Case drain pressure must not exceed 2 bar absolute and must not exceed suction port pressure by more than 0.5 bar. The drain line end should always remain submerged below the reservoir oil level to prevent air ingestion. Case drain ports (L and L1) must not be interchanged.

4. First Start-Up Procedure

Fill the pump housing with clean hydraulic oil before first start. Run at 600-800 rpm unloaded for 5-10 minutes to purge air. Confirm no suction line leakage and steady oil flow from the case drain line before gradually increasing speed and loading to rated conditions. In low-temperature environments, use anti-wear hydraulic oil with a viscosity index of no less than 140 and pre-heat the system before startup.

5. Routine Maintenance

Replace hydraulic oil filters every 2,000 operating hours or annually. Periodically inspect the pump exterior for leaks and check the drive shaft seal for aging or cracks. If flow decline or pressure instability is observed, prioritize inspection of the valve plate and piston-cylinder wear. Recommended overhaul interval: no more than 8,000 operating hours or 5 years. Always refer to Bosch Rexroth official instruction manual RE 92711 during installation.