The Bosch Rexroth A1VO Series 10 is an axial piston variable pump designed for open circuit hydrostatic drives, primarily used in mobile applications, and is ideal for smaller tractors.
Traditionally, an open center system with a fixed pump continuously draws fluid from the tank, providing hydraulic flow regardless of power demands. However, load-sensing systems that use a variable pump adapt to the exact power requirements, reducing fuel consumption and emissions — which is exactly what the A1VO axial piston variable pump does.
NOTE: Documentation for the A1VO Series 10 pump is available at the end of the article.
Here are 12 things you should know about working with the A1VO Series 10 pump.
1. What is the intended use of the A1VO Series 10?
The A1VO Series 10 is an axial piston variable pump designed for hydrostatic drives in open circuits. It can be used as a pump in mobile applications such as tractors. The pump generates, controls, and regulates hydraulic fluid flow that is proportional to drive speed and displacement. It is only approved for use with suitable hydraulic fluids as specified in the manual.
2. What are the main components of the A1VO Series 10 and how do they function?
The main components of the A1VO Series 10 pump are the drive shaft, cylinder, pistons, swashplate, control plate, and valve. The drive shaft transfers torque and rotation from the engine. The pistons move axially within the cylinder bores and are held against the swashplate by springs. As the swashplate rotates, it causes the pistons to reciprocate, drawing in and displacing hydraulic fluid to provide flow. The control plate ports regulate fluid intake and discharge. The swashplate angle controls displacement. It is adjusted by a hydraulic stroke piston.
3. What are the technical specifications – displacement, pressure rating, speed range, etc?
The displacement ranges from 16-250 cm3/rev depending on the model. The pressure rating is up to 350 bar. The speed range is up to 3800 rpm.
4. What kind of fluids can be used with this pump? What cleanliness levels are required?
The A1VO Series 10 is designed for use with mineral oil-based hydraulic fluids. The minimum fluid cleanliness level is 20/18/15 per ISO 4406. Level 19/17/14 is required at high temps above 90C.
5. What installation positions are possible and what needs to be considered for each?
The possible installation positions are:
- Below reservoir
- Inside reservoir
- Above reservoir.
Suction conditions, case drain routing, fill/bleed ports vary based on position. Limitations exist for inside reservoir installation.
See section 7.3 in the A1VO Series 10 Instruction Manual for details.
6. What are the port assignments and hydraulic schematic?
There is a suction port (S), case drain ports (L1, L2), and high pressure port (B). For open circuit, connect S to reservoir, L1/L2 to tank, B to system high pressure line.
See section 7.4.8 in the manual for port details.
7. What procedures are required for installation, commissioning, and maintenance?
- Installation — secure pump, connect hydraulics & electrics per schematic, remove transport plugs.
- Commissioning — fill/bleed, check direction of rotation, test hydraulic supply, perform functional test.
- Maintenance — inspect & change fluid regularly, check pressures & leaks, follow maintenance schedule.
8. How is the pump controlled? What control modes are available?
It is controlled by adjusting the swashplate angle. This changes displacement and flow output. Controls like pressure compensator, load sensing, and electro-proportional control are available.
9. What troubleshooting guidance is provided? What are potential causes and remedies for issues?
Table 14 in the A1VO Series 10 Instruction Manual lists potential faults, causes, and remedies related to noise, flow, pressure, temperature, etc. For example, insufficient flow could be caused by low speed, suction issues, or a worn pump.
10. What safety precautions need to be taken when installing, operating, and maintaining the pump?
- Depressurize and de-energize the system before working on the pump.
- Transport and lift safely using proper equipment.
- Remove protective plugs before use.
- Ensure a clean work environment.
- Follow all warnings and instructions in the manual.
11. What is the warranty and service/repair policy? Where can spare parts be obtained?
The original manufacturer warranty covers the product in the delivered configuration if operated correctly.
Wooster Hydrostatics can perform service and repairs using genuine OEM replacement parts.
For repair, service, or genuine OEM replacement units, please contact Wooster Hydrostatics:
- Free Quote Request
12. What is the proper disposal procedure at end of life?
Fully drain and dismantle the pump into individual materials like steel, aluminum, plastic, electronics, etc., and dispose of them according to local regulations.
Benefits of the Bosch Rexroth A1VO Series 10 Axial Piston Pump
The A1VO optimizes power usage in small tractors from high-demand tasks like using the front loader to low-demand tasks like driving from one field to another, ensuring only the necessary hydraulic power is supplied for the task, which helps save on fuel.
Further, when tractors have hydropneumatic systems for axles and cabin suspension, the A1VO enhances vibration damping by supplying hydraulic fluid only when needed. During fieldwork, implementing actions like raising and lowering attachments, the hydraulic system mainly operates in the partial load range, saving energy and fuel.
Incorporating the EHR hitch control from Rexroth further enhances efficiency by ensuring that position control, ground contact pressure, and vibration damping require less energy and fuel compared to a fixed displacement system.
Estimated Fuel Savings
The A1VO pump offers fuel savings in various tractor activities. Over an average tractor lifespan of 6,000 hours, it can reduce diesel consumption by 10,000 liters, resulting in significant cost savings that outweigh the initial investment.