Testing The Hydraulic Fluid Supply - Bosch Rexroth A10VO Instruction Manual

44/60 Commissioning
Bosch Rexroth AG, A10VO, A10VSO, A10VNO, A10VSNO Series 52 and 53, RE 92703-01-B/04.2018
To ensure the functional reliability of the axial piston unit, cleanliness level 20/18/15
according to at least ISO 4406 is necessary for the hydraulic fluid. At a hydraulic
fluid viscosity of less than 10 mm²/s (e.g. due to high temperatures during short-
term operation) at the drain port, a min. cleanliness level of 19/17/14 as defined in
ISO 4406 is required. For permissible viscosities and temperatures, see data sheets
92703, 92735 and 92741.
1. Place a drip tray under the axial piston unit to collect any hydraulic fluid that may
leak.
NOTICE! Contaminated hydraulic fluid!
The cleanliness levels of commercial hydraulic fluid are usually insufficient for our
components.
▶ Use a suitable filter system to filter hydraulic fluids during filling to minimize solid
particle contamination and water in the hydraulic system.
2. Fill and air bleed the axial piston unit using the appropriate ports; see chapter 7.3
"Installation position" on page 26. Also fill the hydraulic lines of the system.
NOTICE! Risk of property damage due to inadequate lubrication!
Product can be damaged or destroyed!
▶ When using a shut-off valve in the suction and/or drain line, make sure the drive
of the axial piston unit can only be started when the shut-off valves are open.
3. When using a shut-off valve in the suction and/or drain line, only operate the axial
piston unit when the shut-off valves are open.
4.
Test the direction of rotation of the drive motor. To do this, run the drive motor
briefly at the lowest rotational speed (inching). Make sure the direction of
rotation of the axial piston unit matches the specification on the name plate; see
chapter 5.3 "Product identification," Fig. 3: A10VO name plate on page 20.
5. Operate the axial piston pump at a low rotational speed (starter speed for
internal combustion engines or inching mode for electric motors) until the
hydraulic system is completely filled and air bled. To verify, drain the hydraulic
fluid at the drain port until there are no bubbles in the fluid.
8.1.2

Testing the hydraulic fluid supply

The axial piston unit should always have a sufficient supply of hydraulic fluid.
For this reason, the supply of hydraulic fluid must be ensured at the start of the
commissioning process.
When you test the hydraulic fluid supply, constantly monitor noise development and
check the hydraulic fluid level in the reservoir. If the axial piston unit becomes louder
(cavitation) or the drain fluid is discharged with bubbles, this is an indication that
the axial piston unit is not being sufficiently supplied with hydraulic fluid.
For information on troubleshooting, see chapter 14 "Troubleshooting" on page 52.
To test the hydraulic fluid supply:
1. Allow the drive motor to run at the lowest rotational speed. The axial piston unit
should be operated without load. Pay attention to leaks and noises.
2.
Check the axial piston unit's drain line during the test. The drain fluid should be
without bubbles.
3. Increase the load and check whether the working pressure rises as expected.