A4VG125EP4DM1/32L A4VG180 A4VG250 Rexroth Variable Pump 400bar

Product Overview

The A4VG125EP4DM1/32L-NXF03F041PH-S together with the A4VG180 and A4VG250 are precision-engineered interchangeable axial piston variable-displacement pumps fully compatible with the Bosch Rexroth A4VG Series. Designed in swashplate configuration for closed-circuit hydrostatic transmissions, flow is proportional to drive speed and displacement and infinitely variable. These units integrate a charge pump, high-pressure relief valves and pressure cut-off for high power density and reliability. They deliver 100% form-fit-function interchangeability with original Rexroth models. Every pump undergoes rigorous 100% simulated operating-condition testing to guarantee volumetric efficiency, boost performance and reliability under continuous rated conditions.

Technical Specifications 

• Models: A4VG125EP4DM1/32L-NXF03F041PH-S (EP control); A4VG180, A4VG250 (Series 32)
• Geometric displacement (Vg max): A4VG125 – 125 cm³/rev; A4VG180 – 180 cm³/rev; A4VG250 – 250 cm³/rev
• Nominal (continuous) pressure: 400 bar
• Peak pressure: 450 bar
• Maximum continuous speed at Vg max: A4VG125 – 2850 rpm; A4VG180 – 2500 rpm; A4VG250 – 2400 rpm
• Minimum speed: 500 rpm
• Flow at nnom and Vg max: A4VG125 approx. 356 L/min; A4VG180 approx. 450 L/min; A4VG250 approx. 600 L/min
• Power at nnom and Δp = 400 bar: A4VG125 approx. 238 kW; A4VG180 approx. 300 kW; A4VG250 approx. 400 kW
• Torque at Vg max and Δp = 400 bar: A4VG125 approx. 796 Nm; A4VG180 approx. 1146 Nm; A4VG250 approx. 1592 Nm
• Control type: EP (electric proportional control) and other DA, HD options
• Charge pump displacement (approx.): A4VG125 – 28.3 cm³/rev; A4VG180 – 39.8 cm³/rev; A4VG250 – 52.5 cm³/rev
• Housing material: High-strength cast iron
• Approximate weight (without through-drive): A4VG125 – 80 kg; A4VG180 – 101 kg; A4VG250 – 156 kg
• Circuit type: Closed circuit
• Series: Series 32

Key Technical Advantages

1. High power-density swashplate design enables infinitely variable displacement with excellent efficiency, ideal for compact closed-circuit hydrostatic transmissions.
2. Integrated charge pump, high-pressure relief valves and pressure cut-off provide comprehensive system protection against overload and cavitation while simplifying circuit design.
3. Electric proportional (EP) control delivers precise, rapid response to electronic signals for accurate flow and direction management in modern control systems.
4. Robust cast-iron housing combined with heavy-duty bearings and precision rotating group ensures high rigidity, vibration resistance and extended service life under continuous high-pressure duty.
5. Full dimensional and functional interchangeability with original Rexroth A4VG units, including mounting, shaft, ports and controls, plus through-drive capability for same-size secondary pumps, allows true drop-in replacement without system modifications.

Application Areas

Suitable for closed-circuit mobile hydrostatic transmissions including crawler excavator travel drives, wheel loaders, bulldozers, harvesters, forestry machinery, port equipment and any application requiring bidirectional high-pressure variable flow with high power density.

Expert Maintenance Tips

Ensure precise shaft alignment and complete boost-circuit integrity during installation to prevent cavitation (maintain absolute pressure at suction port ≥ 0.8 bar). Confirm case drain is correctly routed to the reservoir within allowable back pressure before start-up. Use specified mineral-based hydraulic oil and maintain recommended cleanliness levels with regular filter changes. Set the pressure cut-off according to the system’s maximum working pressure. When using through-drive, observe torque limits of the secondary pump. Periodically inspect the port plate, pistons and charge pump; replace serviceable wear components as needed to restore performance. Avoid prolonged over-pressure or overspeed operation.