Bosch rexroth MBT, Manual

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Series connection
Fig. 9-13: Series connection of liquid-cooled drive components
In series connection, the same coolant stream flows through all components
that are to be cooled. Each component has a pressure drop between coolant
inlet and coolant outlet. The individual pressure drops add up to the overall
pressure drop of the drive components.
Series connection does not permit any individual selection of the flow quantity
required for the individual components to be made. It is only recommended if
the individual components that are to be cooled need approximately the
same flow quantity and only cause a small pressure drop or if they are instal‐
led very far away from the heat removal device.
Δp Pressure drop
Q Flow quantity
Fig. 9-14: Pressure drop and flow rate in series connection of hydraulic compo‐
nents
The following disadvantages of series connection must always be taken into
account:
●
The required system pressure corresponds to the sum of all pressure
drops of the individual components. This means a reduced hydraulic op‐
erational safety due to a high system pressure.
● The temperature level of the coolant incresaes from one component to
the next. Each heat dissipation in the coolant rises its temperature (un‐
symmetrical machine heating )
● Some components may not be cooled as required since the flow quanti‐
ty cannot be selected individually.
Combination of series and parallel
connection
Combining series and parallel connections of the drive components that are
to be cooled permits the benefits of both connection types to be used.
MBT High Synchronous Torque Motors 275/409
Application notes
R911298798_Edition 08 Bosch Rexroth AG