A4VSO500DR/30R-PPH25N00 Rexroth Axial Piston Pump 500cc 350 Bar

Product Overview

The A4VSO500DR/30R-PPH25N00 belongs to the Bosch Rexroth A4VSO Series 30 open-circuit swashplate axial piston variable displacement pump family, with a displacement of 500 cm³/rev, DR pressure control, and right-hand rotation. The pump delivers a nominal working pressure of 350 bar (5075 psi), maximum pressure of 400 bar (5800 psi), maximum speed of 1320 rpm, maximum flow of 660 L/min, maximum power of 385 kW (at Δp=350 bar), and maximum torque of 2783 Nm.

The A4VSO family covers displacements from 40 to 1000 cm³/rev (A4VSO40/71/125/180/250/355/500/750/1000), featuring a swashplate design for hydrostatic drives in open-circuit operation. Flow is proportional to input drive speed and displacement, with infinitely variable output flow by adjusting the swashplate angle. The series features excellent suction characteristics, low noise levels, long service life, high power-to-weight ratio, and short control response times. The drive shaft absorbs axial and radial loads, and the mounting position is optional.

The A4VSO500DR/30R-PPH25N00 is a complete model code where A4VSO indicates the swashplate axial piston variable pump for open circuit, 500 indicates the 500 cm³/rev displacement class, DR indicates pressure control, 30 indicates Series 30, R indicates right-hand rotation (clockwise, viewed from shaft end), and PPH25N00 is the mounting flange, drive shaft, port configuration, and seal option code. The mounting flange, drive shaft spline, and port layout are identical to the original Rexroth pump, enabling direct bolt-on replacement without system modification or adapter plates.

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.

Technical Specifications 

Model Identification:

• A4VSO500DR/30R-PPH25N00 — A4VSO Series 30, 500 cm³/rev, DR pressure control, right-hand rotation (CW)

• Model code breakdown: A4VSO=swashplate axial piston variable pump (open circuit), 500=displacement 500 cm³/rev, DR=pressure control, 30=Series 30, R=right-hand (clockwise), PPH25N00=mounting flange, drive shaft, port and seal configuration code

Displacement (A4VSO Full Series):

• A4VSO40: 40 cm³/rev

• A4VSO71: 71 cm³/rev

• A4VSO125: 125 cm³/rev

• A4VSO180: 180 cm³/rev

• A4VSO250: 250 cm³/rev

• A4VSO355: 355 cm³/rev

• A4VSO500: 500 cm³/rev

• A4VSO750: 750 cm³/rev

• A4VSO1000: 1000 cm³/rev

Pressure Ratings:

• Nominal pressure: 350 bar (5075 psi)

• Maximum pressure: 400 bar (5800 psi)

Speed Range (A4VSO500):

• Maximum speed: 1320 rpm

• Reference max. speeds: A4VSO71 = 2200 rpm, A4VSO125/180 = 1800 rpm, A4VSO250 = 1500 rpm, A4VSO355 = 1500 rpm, A4VSO750 = 1000 rpm

Flow and Power (A4VSO500, Δp=350 bar):

• Maximum flow: 660 L/min

• Maximum power: 385 kW

• Maximum torque: 2783 Nm

• Weight: Approximately 320 kg

• A4VSO full series reference: A4VSO71 = 91 kW / 395 Nm; A4VSO125 = 131 kW / 696 Nm; A4VSO180 = 189 kW / 1002 Nm; A4VSO250 = 219 kW / 1391 Nm; A4VSO355 = 311 kW / 1976 Nm; A4VSO750 = 525 kW / 4174 Nm; A4VSO1000 = 583 kW / 5565 Nm

Control Types:

• DR Pressure Control — The pressure controller limits the maximum pressure at the pump outlet within the control range of the variable pump. When system pressure reaches the set value, the pump automatically reduces the swashplate angle to maintain constant pressure

• Optional controls: DP (pressure controller for parallel operation), DRG (remote controlled pressure controller), FR (flow control), DFR (pressure and flow control), LR (hyperbolic power control), MA (manual control), EM (electric motor control), EO (electronic proportional control), HD (hydraulic control), DS (secondary control speed control)

Structural Parameters:

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

• Design series: Series 1, 2 and 3

• Mounting flange: SAE standard flange

• Drive shaft: SAE involute splined shaft

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

• Port connections: SAE flange per SAE J518C

• Through-drive: Supported, suitable for axial piston pumps and gear pumps up to the same nominal size

• Mounting position: Optional, any position

• Housing material: Cast iron

Hydraulic Fluid and Operating Conditions:

• Recommended fluid: Mineral oil-based anti-wear hydraulic oil

• Operating viscosity range: Optimal 10-39 cSt

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

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

Key Technical Advantages

1. Swashplate Design Delivers High Power Density

The A4VSO series features a swashplate design for hydrostatic drives in open-circuit operation. Flow is proportional to input drive speed and displacement, with infinitely variable output flow by adjusting the swashplate angle. The A4VSO500 achieves 350 bar nominal working pressure and 400 bar maximum pressure at 500 cm³/rev displacement, with maximum flow of 660 L/min and maximum power of 385 kW at rated speed.

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

The A4VSO series employs a standardized model code system: each character in the A4VSO500DR/30R-PPH25N00 corresponds to specific parameters—displacement class (500), control type (DR), series designation (30), rotation direction (R=right-hand), mounting flange and drive shaft configuration (PPH25), and other complete specifications. The mounting flange, drive shaft spline, and port layout are identical to the original Rexroth pump, enabling direct bolt-on replacement without piping modification or adapter plates.

3. DR Pressure Control Ensures Precise Constant Pressure Output

The DR pressure controller on the A4VSO500DR/30R-PPH25N00 limits the maximum pressure at the pump outlet within the control range of the variable pump. When system pressure reaches the set value, the pump automatically reduces the swashplate angle to maintain constant pressure. Pressure control response is fast with short control times, ensuring precise and stable system pressure. Optional remote pressure control (DRG) and pressure controller for parallel operation (DP) are available for different system control requirements.

4. Excellent Suction Characteristics and Low Noise Operation

The A4VSO series features a swashplate design with excellent suction characteristics, ensuring smooth operation even at low inlet pressures. The optimized port plate design and swashplate-type rotary group structure reduce operating noise levels, making the pump suitable for industrial environments with strict noise emission requirements. The full series offers long service life and low operating and maintenance costs.

5. High Power-to-Weight Ratio and Flexible System Integration

The A4VSO series offers a high power-to-weight ratio and compact cast iron housing design, supporting 100% through-drive for 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 mounting position is optional in any direction, providing equipment manufacturers with flexible system integration solutions. The drive shaft absorbs axial and radial loads, enhancing system layout flexibility.

Application Areas

• Metallurgical machinery (rolling mills, forging presses, extrusion presses)

• Forging machinery and press hydraulic power systems

• Aluminum processing machinery and metal recycling machinery

• Marine hydraulic systems and deck machinery

• Papermaking machinery and forestry machinery

• Hydropower and railway shield tunneling hydraulic drive systems

• Petrochemical and mining machinery hydraulic systems

• Construction machinery (excavators, cranes, concrete pump trucks)

Expert Maintenance Tips

1. Pre-Installation Model Verification

Verify the complete model code on the pump nameplate before installation. The A4VSO500DR/30R-PPH25N00 is configured for right-hand rotation (R code). The DR pressure controller factory setting must match the equipment hydraulic system requirements. Ensure drive shaft-to-coupling concentricity within 0.05 mm to prevent premature seal failure from radial loads. The mounting position is optional, but ensure the case drain port faces upward or maintains oil level at or above the pump centerline.

2. Hydraulic Fluid Cleanliness Requirements

Use mineral oil-based anti-wear hydraulic oil with optimal operating viscosity range of 10-39 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. Flush the system thoroughly before first operation. During commissioning, oil must be injected into the pump housing and it must be filled up during operation.

3. Case Drain Line Installation

Provide a properly sized case drain line. The use of check valves in the case drain line must be avoided. The tank drain line must be connected directly back to the tank without any change in line size. To reduce operating noise levels, all connecting lines (oil suction, pressure and tank drain lines) must be separated from the tank using flexible elements.

4. First Start-Up Procedure

Before first start, confirm the suction line is properly sealed, the reservoir is at the correct level, and oil level is at or above the pump centerline. Run at low speed 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. The DR pressure controller setting can be adjusted via the adjustment screw on the control valve.

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. System design, installation, and commissioning must be carried out by trained technicians and dealers. 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 92050 during installation.