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Bosch Rexroth AG
Drive modules | RE 51150-B/07.11
Maintenance and repair
Before commencing the inspection, cleaning should be undertaken if necessary.
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Always ensure cleanliness when working at the drive module
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.
Filling level
10.2.1
Carry out a filling level control in an interval of 8 operating hours.
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The oil level is not constant during operation of the drive module.
Level changes result from the different volume requirements of plunger and
differential cylinder and/or the absorption/delivery of hydraulic fluid in hydraulic
accumulators during a working cycle.
Due to the variable conditions mentioned above a complete working cycle of the
machine must be observed when undertaking the visual inspection of the oil level.
This will enable you to determine whether hydraulic fluid needs to be refilled or
topped up, and if so, by how much.
During operation, the oil level must neither exceed the upper mark nor fall below
the lower mark. If the minimum filling level is undershot, there is a risk of pump
failure due to cavitation.
If the maximum filling level is exceeded, this may have been caused by the
thermal expansion of the hydraulic fluid or by fluid entry (e.g. water in the case of
internal leaks of the oil/water cooler).
Optionally, the drive module may be equipped with an electric fluid level indicator.
The switching points can be seen from the technical specification and the
circuit diagram.
Measures to be taken if the maximum filling level is exceeded:
Approximately determine the expansion by temperature increase
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(delta V = thermal expansion coefficient x delta T).
Correct the filling level.
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If the maximum filling level is exceeded due to assumed water ingress:
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Close the water valves (shut-off the cooling water supply).
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Draw an oil sample at the lowest point of the tank and check it for wa-
–
ter content.
If the suspected water ingress is confirmed, you should complete the ma-
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chine working cycle and then shut down safely.
Repair the oil/water coolers according to the manufacturer's specifications
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or exchange them, if necessary.
Perform more extensive control measures and implement the following mea-
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sures depending on these results:
Clean the hydraulic fluid or replace it.
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Carry out a flushing process, if necessary.
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Check the hydraulic fluid for admissible water content.
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Oil temperature (optional)
10.2.2
Check the oil temperature at intervals of 8 operating hours.
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If specified in the order, the drive module may be equipped with a tempera-
ture switch.
Oil level
level monitoring
Maintenance, repair
