A2V500HDLOR A2V500DRH2 Rexroth Bent Axis Pump 500cc

Product Overview

The A2V500HDLOR-5GPK/106 (Material No. R902408544) and A2V500DRH2GR5GP are the 500 cc-class core models within the Bosch Rexroth A2V series 5 of bent-axis variable displacement axial piston pumps. The A2V series features a bent-axis design where displacement is infinitely variable via changes in the swash axis inclination angle, for hydrostatic drives in closed, semi-closed, and open circuits. Maximum flow is proportional to drive speed and displacement, and is infinitely variable at constant drive speed.

A2V Series Core Features: New, simplified high performance rotary group with enhanced technical data and well-proven spherical control area; heavy duty rolling bearings for intermittent high pressure operation; for continuous duty at high pressures, hydrostatic bearings are available. Improved port plate design and compact design reduces noise level by 5 dBA. Operation on fire-resistant fluids is possible. The A2V series spans displacements from 12 to 1000 cm³/rev, with A2V500 alongside A2V250, A2V355, A2V915, and A2V1000 in the large displacement range.

Model Code Breakdown (for procurement and engineering reference):

A2V500HDLOR-5GPK/106:

• A2V: Rexroth bent-axis variable displacement axial piston pump series

• 500: Nominal size (NG), geometric displacement 500 cm³/rev

• HD: Hydraulic control, pressure related

• LOR: Additional functions. L = Constant HP control; O = without boost pump; R = rotation direction code

• -5: Series 5

• GPK: G = housed pump design; P = keyed shaft; K = additional configuration code

• /106: Design number

• R902408544: Rexroth material number

A2V500DRH2GR5GP:

• A2V: Rexroth bent-axis variable displacement axial piston pump series

• 500: Nominal size (NG), geometric displacement 500 cm³/rev

• DRH2: Pressure regulator, hydraulically operated; 2 = with pressure unloading

• G: Housed pump design

• R: Clockwise rotation (viewed from shaft end)

• 5: Series 5

• G: Design variant

• P: Keyed shaft

About A2V915: The A2V915 is the extra-large displacement specification within the A2V series, with a geometric displacement of 915 cm³/rev, representing the extreme level of productization in the bent-axis pump high-flow direction. This specification holds milestone significance in the industrial hydraulics field.

Drop-in Replacement Advantage: Manufactured to exact Rexroth OEM specifications, these pumps achieve complete drop-in interchangeability with the original A2V series for mounting flange, shaft dimensions, port layout, and control module interface. The A2V series is compatible with Uchida and other brand equivalents. Every pump undergoes 100% simulated load testing prior to shipment, validating 350 bar pressure loading, variable displacement control response, and volumetric efficiency under conditions replicating real-world duty cycles.

Technical Specifications 

A2V500 Series General Specifications:

• Series: Rexroth A2V Series 5 (Bent-Axis Variable Displacement Pump)

• Nominal Size: NG 500

• Geometric Displacement: 500 cm³/rev

• Nominal Pressure: 350 bar (continuous)

• Peak Pressure: 400 bar (intermittent)

• Maximum Speed (Closed Circuit): 2000 rpm

• Maximum Speed (Semi-Closed Circuit, Vg max): 1060 rpm

• Maximum Speed (Open Circuit, Vg max): 1200 rpm

• Maximum Output Flow (Closed Circuit): 1000 L/min

• Maximum Output Flow (Semi-Closed Circuit, Vg max): 514 L/min

• Maximum Output Flow (Open Circuit, Vg max): 582 L/min

• Maximum Power (Δp = 350 bar, Closed Circuit): 583 kW

• Maximum Power (Δp = 350 bar, Semi-Closed Circuit): 309 kW

• Maximum Power (Δp = 350 bar, Open Circuit): Approx. 291 kW

• Control Type: HD (Hydraulic Control, Pressure Related), DRH2 (Pressure Regulator, Hydraulically Operated with Unloading)

• Additional Functions: LOR (Constant HP Control)

• Mounting Flange: SAE B 2-bolt flange

• Shaft: Keyed shaft (P code)

• Housing Material: High-strength cast iron

• Seal Material: NBR, suitable for mineral oil-based and fire-resistant hydraulic fluids

• Fluid Cleanliness: ISO 4406 18/15/12 or better

• Recommended Fluid: ISO VG32 / VG46 anti-wear hydraulic oil

Model A2V500HDLOR-5GPK/106 Configuration:

• Model Code: A2V500HDLOR-5GPK/106

• Material Number: R902408544

• Control Type: HD — Hydraulic Control, Pressure Related

• Additional Function: LOR — Constant HP Control

• Rotation: Per R code

• Shaft: Keyed shaft (P code)

• Series: 5

Model A2V500DRH2GR5GP Configuration:

• Model Code: A2V500DRH2GR5GP

• Material Number: R910906258

• Control Type: DRH2 — Pressure Regulator, Hydraulically Operated with Unloading

• Rotation: Clockwise (viewed from shaft end, R code)

• Shaft: Keyed shaft (P code)

• Series: 5

A2V Series Large Displacement Size Reference:

• A2V250: 250 cm³/rev, closed circuit max speed 2500 rpm, max flow 625 L/min

• A2V355: 355 cm³/rev, closed circuit max speed 2240 rpm, max flow 795 L/min

• A2V500: 500 cm³/rev, closed circuit max speed 2000 rpm, max flow 1000 L/min

• A2V915: 915 cm³/rev, representative specification of bent-axis high-flow productization

• A2V1000: 1000 cm³/rev, closed circuit max speed 1600 rpm, max flow 1600 L/min

Key Technical Advantages

1. Bent-Axis Design with High Power Density
The A2V series employs a bent-axis design where the piston axis is angled relative to the drive axis. The piston lateral force exerted on the cylinder block is minimal, reducing the tilting moment between the cylinder block and valve plate, allowing the rotary group to maintain a stable hydrostatic bearing film at high speeds. The A2V500 achieves maximum power of 583 kW and maximum flow of 1000 L/min in closed circuit at 350 bar nominal pressure. The new, simplified high performance rotary group with well-proven spherical control area further enhances power density and operational stability.

2. Heavy-Duty Rolling Bearings with Hydrostatic Bearing Option
The A2V series is equipped with heavy duty rolling bearings specifically designed for intermittent high pressure operation. For applications requiring continuous high-pressure operation, hydrostatic bearings are available, effectively reducing bearing wear rates and extending maintenance intervals. This dual bearing configuration enables the A2V series to flexibly adapt to operating conditions ranging from intermittent shock loads to continuous high-pressure operation.

3. Multi-Mode Hydraulic Control with Constant HP Function
The A2V500HDLOR-5GPK/106 is equipped with HD hydraulic control (pressure related) and integrates LOR constant HP control function. The HD control type drives the servo piston through pilot pressure signals to change the swash axis inclination angle for stepless displacement adjustment. The LOR additional function enables the pump to automatically reduce displacement along a constant power curve as system pressure rises, achieving precise matching between hydraulic system power and prime mover output power while effectively preventing prime mover overload. The A2V500DRH2GR5GP is equipped with a DRH2 hydraulically operated pressure regulator with unloading function, suitable for systems requiring pressure unloading control.

4. Port Plate Design with 5 dBA Noise Reduction
The A2V series employs improved port plate design and compact construction, reducing noise levels by 5 dBA compared to previous generation products. Metering slot pre-compression and pre-decompression angles are optimized to minimize pressure spikes and flow pulsation during piston chamber high-to-low pressure transitions. The compact housing design further suppresses structural vibration and fluid-borne noise propagation.

5. Fire-Resistant Hydraulic Fluid Compatibility
The A2V series is compatible with fire-resistant hydraulic fluids, providing safe hydraulic power solutions for industrial applications with fire risk (such as metallurgy, mining, and marine). The seal material is NBR, with standard configuration suitable for mineral oil-based hydraulic fluids. For HFD and other fire-resistant hydraulic fluid applications, select FKM seal configuration.

6. Complete Primary Units with Modular System
The A2V series offers complete primary units, integrating all auxiliary devices required for closed circuits, including valve blocks and boost pumps, forming ready-to-install closed-circuit pump groups. Modular design supports flexible combinations of various control modes and additional functions. Standardized mounting interfaces (SAE B 2-bolt flange) require no adaptation for replacement, significantly reducing equipment downtime.

Application Areas

• Metallurgical Equipment: Rolling mill hydraulic screwdown systems, continuous casting machine hydraulic systems, steelmaking furnace hydraulic power sources

• Forging Equipment: Large open-die forging presses, closed-die forging press main hydraulic pumps

• Mining & Tunneling: Tunnel boring machine thrust hydraulic systems, mine hoist hydraulic drives, roadheader hydraulic systems

• Marine & Offshore: Ship deck machinery hydraulic systems, large steering gear hydraulic power units, marine winch hydraulic drives

• Test Equipment: Large hydraulic test benches, fatigue testing machine hydraulic power sources

• Power Generation: Turbine bypass system hydraulic actuators, hydro turbine governor hydraulic systems

• Industrial Hydraulic Power Units: Large hydraulic power units, central oil supply systems

Expert Maintenance Tips

1. Hydraulic Fluid Cleanliness
The A2V series HD hydraulic control servo spool and DRH2 pressure regulator operate with extremely tight clearances and are highly sensitive to particulate contamination. System fluid cleanliness must meet ISO 4406 18/15/12 or better. Recommended fluids are ISO VG32 or VG46 anti-wear hydraulic oils. Install a 10 μm absolute-rated filter element at the pump inlet. Replace elements at 500 hours after first commissioning, then every 1,000 operating hours or 6 months, whichever comes first.

2. HD Hydraulic Control and LOR Constant HP Control Commissioning
The A2V500HDLOR-5GPK/106 HD control type drives the servo piston through pilot pressure signals. During commissioning, first confirm that pilot pressure supply is normal and the control pressure setting meets system requirements. The LOR constant HP control function’s power control curve start point is mechanically adjustable. During commissioning, set the power control start point with the pump at neutral (zero displacement), then apply load at rated speed and adjust the screw to set the power curve (P×Q=constant). The power control setting must ensure that the system does not exceed the prime mover’s available power at maximum working pressure.

3. DRH2 Pressure Regulator Setting and Unloading Function Check
The A2V500DRH2GR5GP is equipped with a DRH2 hydraulically operated pressure regulator with unloading function. Set the pressure regulator 15–20 bar above the maximum working load pressure, never exceeding the 350 bar nominal pressure. Check the unloading function every 2,000 operating hours to confirm the unloading solenoid operates correctly and the unloading pressure setting meets system requirements. Adjust only with the system at zero load. Rotate the adjustment screw slowly.

4. Case Drain Line Requirements
The case drain line must return directly to the reservoir. Maximum permissible back pressure is 2 bar (0.2 MPa). The drain outlet must terminate below oil level at all times to prevent air ingestion. The drain line diameter must not be smaller than the pump case drain port size. For 500 cc class large displacement pumps, case drain flow is substantial — drain line design must fully account for flow demand to avoid excessive case pressure from pipe resistance.

5. Pre-Start Priming and Air Bleeding
Before first start, fill the pump housing with clean hydraulic fluid through the case drain port. After installation, turn the drive shaft by hand several revolutions to confirm free rotation without binding. Position the control at neutral (zero displacement) and run at low speed for 5–10 minutes. Verify continuous bubble-free flow from the case drain. Only then apply load.

6. Fire-Resistant Hydraulic Fluid Compatibility Confirmation
If the system uses HFD or other fire-resistant hydraulic fluids, confirm that the pump seal material configuration is FKM (fluororubber) and that the hydraulic fluid brand and model are compatible with Rexroth technical specifications. The A2V series standard configuration is NBR seals, suitable for mineral oil-based hydraulic fluids. When changing hydraulic fluid types, simultaneously check seal material compatibility and perform system flushing and fluid replacement according to Rexroth technical manual requirements.