A10VSO Series Axial Piston Pump | Bosch Rexroth

Filling and Air Bleeding:

• The axial piston unit must be filled with hydraulic fluid and air bled during commissioning and operation. This is also necessary after a longer standstill to prevent the axial piston unit from running dry due to empty hydraulic lines.
• Special attention must be paid to complete filling and air bleeding, especially in the “drive shaft upwards” or “drive shaft downwards” installation positions to avoid dry running.

Case Drain Fluid Management:

• The case drain fluid in the unit’s interior must be directed to the reservoir via the highest case drain port (L1, L2, L3).
• For combinations of multiple units, ensure that the respective case pressure in each unit is not exceeded. In cases of pressure differences at the drain ports of the units, the shared drain line must be modified to ensure the minimum permissible case pressure of all connected units is not exceeded. If this is not possible, separate drain lines must be installed if necessary.

Noise Reduction:

• To achieve favorable noise values, decouple all connecting lines using elastic elements and avoid above-reservoir installation.

Suction and Case Drain Lines:

• In all operating states, the suction line and case drain line must flow into the reservoir below the minimum fluid level.
• The permissible suction height (hS) is a result of the overall pressure loss but must not be greater than hS max = 800 mm. The minimum suction pressure at port S must also not fall below 12 psi (0.8 bar) absolute during operation.

Installation Positions:

• Recommended installation positions are 1 and 3 for below-reservoir installations, meaning the axial piston unit is installed outside of the reservoir below the minimum fluid level.
• Inside-reservoir installation means the pump is installed within the minimum reservoir fluid level.
• For above-reservoir installations, observe the maximum permissible suction height (hS max = 800 mm). A check valve in the case drain line is only permissible in individual cases and requires approval.

Minimum Necessary Spacing:

• When designing the reservoir, ensure adequate distance between the suction line and the case drain line to prevent the heated, return flow from being drawn directly back into the suction line.