Viktor had three quotes on his desk for the same machine. One listed an A10VSO 71 DFR1/31R. Another listed an A4VSO 180 DR/30R. The third simply said “Rexroth axial piston pump, 71 cc.” The prices were thousands of dollars apart, and none of the suppliers explained why. He needed the right bosch rexroth axial piston pump for a rebuilt injection press, but the model codes were doing more to confuse than clarify.
This is the everyday reality for procurement engineers and maintenance managers. Bosch Rexroth builds some of the most widely specified axial piston pumps in the world, yet the differences between series are not obvious from a part number. The A10VSO, A4VSO, and A11VO share the same swashplate variable-displacement architecture, but they are engineered for different pressures, displacements, and duty cycles. Pick the wrong one and you either overpay for capacity you do not need or under-spec a pump that fails early.
In this guide, we break down the three core Rexroth open-circuit axial piston pump series using official data sheet specifications. You will learn how to read a Rexroth model code, which control option matches your system, and how to choose between genuine, aftermarket, and repair-kit sourcing. By the end, you will match the pump to the application instead of guessing from a price list. Want to learn more about the axial piston hydraulic pump? Please check out our axial piston hydraulic pump complete guide.
Need help matching a Rexroth pump to your system? Contact us for a specification cross-reference before you order.
What Makes Bosch Rexroth Axial Piston Pumps the Industrial Benchmark?
Bosch Rexroth dominates the high-pressure hydraulic pump market because its designs combine high power density with modular control options. The company offers axial piston pumps, gear pumps, vane pumps, and complete hydraulic systems, but the A10VSO, A4VSO, and A11VO series remain the reference points for open-circuit variable displacement pumps.
A bosch rexroth axial piston pump uses a cylinder block with multiple pistons arranged parallel to the drive shaft. A swashplate changes the piston stroke, which changes displacement and therefore flow. This design delivers high pressure, high efficiency, and infinitely variable output in a compact package. The result is a pump family used in everything from injection molding machines to excavators.
Three characteristics make these pumps the default choice for many specifiers:
- Pressure and power density: Continuous ratings up to 350 bar and peak ratings up to 400 bar in a compact housing.
- Modular controls: One pump body accepts pressure control, load-sensing flow control, power limiting, and electro-hydraulic proportional controls.
- Global support network: Replacement parts, service manuals, and authorized distributors are available in most industrial regions.
These strengths come at a cost premium. The challenge for buyers is not whether Rexroth is good; it is which Rexroth series fits the specific machine.
Series at a Glance: A10VSO vs A4VSO vs A11VO
The fastest way to separate the three series is to look at pressure, displacement range, and intended application.
| Series | Circuit | Nominal Pressure | Peak Pressure | Displacement Range | Primary Application |
|---|---|---|---|---|---|
| A10VSO | Open | 280 bar | 350 bar | 18–140 cm³/rev | Industrial machinery, injection molding, machine tools |
| A4VSO | Open | 350 bar | 400 bar | 40–1000 cm³/rev | Heavy presses, steel mills, marine, test rigs |
| A11VO | Open | 350 bar | 400 bar | 40–260 cm³/rev | Mobile equipment, excavators, wheel loaders |
The A10VSO is the general-purpose industrial workhorse. The A4VSO is the heavy-duty, high-pressure, large-displacement option. The A11VO is the mobile specialist with self-priming capability and an optional charge pump. If you remember only one thing, remember this: A10VSO for industrial precision, A4VSO for heavy industrial power, A11VO for mobile open-circuit duty.
A10VSO Series: The Industrial All-Rounder
The A10VSO is a variable-displacement axial piston pump designed for open-circuit industrial systems. Its swashplate design uses hydrostatically unloaded cradle bearings to reduce wear on the adjustment mechanism and keep noise low. The result is a pump that fits neatly into machine tools, injection molding machines, hydraulic power units, and light presses.
A10VSO Specifications (Series 31)
| Size (NG) | Displacement (cm³/rev) | Max Speed at Vg max (rpm) | Nominal Pressure (bar) | Peak Pressure (bar) |
|---|---|---|---|---|
| 18 | 18 | 3,300 | 280 | 350 |
| 28 | 28 | 3,000 | 280 | 350 |
| 45 | 45 | 2,600 | 280 | 350 |
| 71 | 71 | 2,200 | 280 | 350 |
| 100 | 100 | 2,000 | 280 | 350 |
| 140 | 140 | 1,800 | 280 | 350 |
The A10VSO covers the displacement range most industrial buyers need. It is compact, relatively quiet, and accepts a wide range of control devices.
Common A10VSO Applications
- Injection molding machines
- CNC machine tools and clamping circuits
- Hydraulic power units
- Lifts and material handling
- Light presses and general industrial machinery
Control Options
The A10VSO offers DR, DRG, DFR/DFR1, DFLR, and DG controls. DR maintains constant pressure. DFR adds load-sensing flow control so the pump delivers only the flow the system demands. DFLR adds power limiting to protect the electric motor. DG is a simple two-point control for max/min displacement switching.
A maintenance manager at a plastics plant recently replaced an A10VSO 71 DFR1/31R on a 250-ton press. The original pump had run for 12,000 hours before case drain flow climbed past the 10% rule. Because he matched the exact model code, the replacement bolted in without changing the piping, coupling, or control settings. The press was back in production on a single shift.
A4VSO Series: The Heavy-Duty Powerhouse
The A4VSO is built for applications where pressure, displacement, and shock load exceed what the A10VSO can handle. It uses heavy-duty bearings and a reinforced housing to support continuous 350 bar operation and peak loads up to 400 bar. The displacement range runs from 40 cm³/rev all the way to 1000 cm³/rev, making it suitable for large presses, steel mills, and marine systems.
A4VSO Specifications (Series 1x/30)
| Size | Displacement (cm³/rev) | Max Speed (rpm) | Flow at nmax (L/min) | Weight Approx. (kg) |
|---|---|---|---|---|
| 40 | 40 | 2,800 | 104 | 39 |
| 71 | 71 | 2,200 | 156 | 53 |
| 125 | 125 | 1,800 | 225 | 88 |
| 180 | 180 | 1,800 | 324 | 102 |
| 250 | 250 | 1,500 | 375 | 184 |
| 355 | 355 | 1,500 | 533 | 207 |
| 500 | 500 | 1,320 | 660 | 320 |
| 750 | 750 | 1,200 | 900 | 460 |
| 1000 | 1000 | 1,000 | 1000 | 605 |
The A4VSO also supports fire-resistant fluids such as HFC and HFD-U in special versions, which matters in steel mills and foundries where fire safety codes restrict mineral oil. Special high-pressure versions with port plate 36 push nominal pressure to 380 bar and peak to 420 bar.
Common A4VSO Applications
- Hydraulic presses and metal forming
- Die casting and forging machines
- Steel mill and metallurgy equipment
- Marine deck machinery and offshore systems
- High-pressure test rigs
When a steel processor upgraded a 600-ton shear line, the engineering team had to choose between an A10VSO 140 and an A4VSO 180. The A10VSO saved money upfront, but the cycle demanded 320 bar continuous pressure and frequent shock loads. They selected the A4VSO 180 DR/30R. The heavier pump cost 45% more, but it eliminated the bearing fatigue and valve-plate scoring that had plagued the smaller unit. Over three years, the A4VSO delivered lower total cost of ownership despite the higher purchase price.
A11VO Series: The Mobile Specialist
The A11VO is a variable-displacement axial piston pump designed primarily for mobile open-circuit hydrostatic drives. It shares the 350/400 bar pressure rating of the A4VSO but packages it in a compact form with features mobile equipment needs: self-priming operation, an optional integrated charge pump/impeller on the A11VLO variant, and externally adjustable power control.
A11VO Specifications (Series 1)
| Feature | Specification |
|---|---|
| Circuit | Open circuit |
| Nominal pressure | 350 bar |
| Peak pressure | 400 bar |
| Displacement sizes | 40, 60, 75, 95, 130, 145, 190, 260 cm³/rev |
| Special feature | Optional charge pump for sizes NG 130–260 |
| Through-drive | Up to same nominal size |
The A11VO is not just an A4VSO with a different label. Its controls and porting are optimized for mobile duty cycles, and the optional impeller helps prevent cavitation when the pump is mounted above the reservoir. This matters on excavators, wheel loaders, and cranes where reservoir geometry and suction conditions are rarely ideal.
Common A11VO Applications
- Excavators and wheel loaders
- Mobile cranes and concrete pumps
- Agricultural machinery
- Logging and forestry equipment
- Material handling vehicles
A fleet manager running twenty excavators standardized on the A11VO 95 LRDS/10R for the main hydraulic pump. The power control lets him limit maximum drive torque across the fleet, protecting diesel engines on hot days. When a unit needed replacement, he sourced a Rexroth-compatible unit with the same mounting, shaft, ports, and control code. The swap took two hours and required no control reprogramming.
How to Read a Rexroth Axial Piston Pump Model Code
Rexroth model codes look cryptic until you read them from left to right. Each segment encodes the pump family, displacement, control type, series version, rotation, and hardware details.
Take the example A10VSO 71 DFR1/31R-PPA12N00:
| Segment | Code | Meaning |
|---|---|---|
| Series | A10VSO | Axial piston variable pump, swashplate, open circuit |
| Displacement | 71 | 71 cm³/rev |
| Control | DFR1 | Pressure and flow controller, X-T plugged |
| Series version | 31 | Series 31 design generation |
| Rotation | R | Clockwise (viewed from shaft end) |
| Mounting flange | P | SAE 2-bolt (example) |
| Drive shaft | P | Keyed shaft (example) |
| Seals | A | NBR seals (example) |
| Ports | 12 | Port configuration code |
| Through-drive | N00 | No through drive |
The most common mistake buyers make is changing one segment without checking the others. A DFR1 control will not behave like a DR control. A left-hand rotation pump will not work on a right-hand drive train. If the nameplate is readable, copy the full code exactly. If the nameplate is missing, measure the mounting flange, shaft type, port layout, and control interface, then cross-reference against the data sheet. Need help matching specs to your system? Our axial piston pump specifications guide explains each rating in more depth.
Control Options Explained
Rexroth control codes determine how the pump responds to system pressure and flow demand. Choosing the right control is as important as choosing the right displacement.
| Control Code | Function | Best For |
|---|---|---|
| DR | Pressure control | Systems needing constant pressure |
| DRG | Remote pressure control | Pressure setting adjusted from a remote pilot line |
| DFR / DFR1 | Pressure and flow (load sensing) | Systems with variable flow demand |
| DFLR | Pressure, flow, and power limiting | Protecting drive motors from overload |
| DG | Two-point control | Simple max/min displacement switching |
| LR | Power / torque control | Mobile and industrial systems with engine/motor limits |
DR and DFR1 are the most common codes on industrial A10VSO pumps. LR appears more often on A4VSO and A11VO units where torque limiting protects the prime mover. For a deeper explanation of how these controls work, see our guide to variable displacement axial piston pump controls.
Choosing the Right Series: Decision Matrix
Use this matrix to narrow the choice before you request a quote.
| If Your System Needs… | Choose |
|---|---|
| Continuous pressure below 280 bar, quiet industrial duty | A10VSO |
| Continuous pressure above 280 bar, heavy shock loads | A4VSO |
| Mobile open-circuit duty, self-priming, compact package | A11VO |
| Displacement under 140 cm³/rev in an industrial machine | A10VSO |
| Displacement above 180 cm³/rev or large actuator flow | A4VSO |
| Mobile equipment with an auxiliary pump through-drive | A11VO |
| Fire-resistant fluid compatibility | A4VSO (special version) |
The right choice balances first cost, operating pressure, duty cycle, and lifecycle cost. An A4VSO in an A10VSO application wastes money and energy. An A10VSO in an A4VSO pressure regime fails prematurely. When in doubt, size for the actual pressure and flow profile, not the largest pump that fits the budget.
Replacement and Sourcing Guidance
Once you know the series and model code, the next decision is how to source the pump. There are four common paths.
| Source | Best For | Considerations |
|---|---|---|
| Genuine Rexroth | Warranty coverage, critical systems | Highest cost, authorized distributor required |
| Authorized distributor | Reliable delivery, factory support | Premium pricing, longer lead times on specials |
| OEM-compatible replacement | Post-warranty maintenance, cost control | Verify test-bench validation and warranty terms |
| Repair kit / rotating group | Minor wear, tight budget | Requires teardown and skilled reassembly |
Genuine Rexroth units are the safest choice when the machine is under warranty or when downtime cost exceeds purchase price. After the warranty period, many maintenance teams choose OEM-compatible replacements to reduce cost without changing mounting geometry. The key is to confirm that the replacement matches the original in displacement, rotation, shaft, ports, seals, and control code.
For buyers managing fleet replacements or bulk procurement, LOYAL INDUSTRIAL PTE. LTD. supplies Bosch Rexroth axial piston pump replacements built to match original specifications. Each unit is pressure-tested before shipment, and we cross-reference by model code or material number to avoid ordering errors.
Sourcing a replacement pump? Send us the model code or a photo of the nameplate and we will cross-reference the specification.
FAQ
What is the difference between A10VSO and A4VSO?
The A10VSO is a medium-pressure industrial pump rated at 280 bar nominal with displacements from 18 to 140 cm³/rev. The A4VSO is a heavy-duty industrial pump rated at 350 bar nominal with displacements from 40 to 1000 cm³/rev. Choose the A4VSO when you need higher pressure, larger flow, or continuous heavy-duty cycling.
Can I use an A10VSO in a mobile application?
The A10VSO is designed for stationary industrial systems with direct flexible coupling and minimal radial shaft load. Mobile applications generally require the A11VO, which is built for self-priming operation, through-drive, and mobile duty cycles.
What does DFR1 mean on a Rexroth pump?
DFR1 stands for a pressure and flow controller with the load-sensing X-port plugged. It combines pressure control with load-sensing flow control, but the system must handle unloading of the X-line externally.
How do I identify my Rexroth axial piston pump model?
The full model code is stamped on the metal nameplate on the pump housing. Copy the complete code including the suffix after the slash. If the nameplate is missing, record the series, displacement, rotation, shaft type, port layout, and control device for cross-reference.
What is the pressure rating of a Bosch Rexroth A11VO?
The A11VO is rated at 350 bar nominal pressure and 400 bar peak pressure, matching the A4VSO. It is designed for open-circuit mobile applications with displacements from 40 to 260 cm³/rev.
Conclusion
A bosch rexroth axial piston pump is not a single product. It is a family of pumps engineered for different pressures, displacements, and duty cycles. The A10VSO handles the bulk of industrial applications quietly and efficiently. The A4VSO steps up to heavy-duty, high-pressure, large-flow systems. The A11VO takes the same pressure capability into mobile open-circuit machinery.
The key to getting the right pump is reading the model code correctly and matching the series to the application. Get that right, and sourcing becomes straightforward. Get it wrong, and even a premium Rexroth pump will underperform or fail early.
If you are comparing quotes, planning a rebuild, or sourcing a replacement, start with the model code and the duty profile. For a fast cross-reference or a technical specification review, contact our team, and we will help you match the right Bosch Rexroth axial piston pump to your system.
