OLF-5 Series
Hydraulic Connection of the OLF
HYDAC FILTER SYSTEMS GMBH
en
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BeWa OLF5_Serie 3433222b en-us 2011-11-14.doc
2011-11-14
Hydraulic Connection of the OLF
The pressure loss in a hydraulic line depends upon:
flow
rate
kinematics
viscosity
pipe
dimensions
fluid
density
The pressure loss can be estimated for hydraulic oils as follows:
Δ
p ~ 6.8 * L / d
4
* Q * V * D
Δ
p = Pressure differential in [bar]
L
= Line length [m]
d
= Internal line diameter [mm]
Q
= Flow rate [l/min]
V
= Kinematic viscosity [mm²/s]
D
= Density [kg/dm³]
Mineral oil based hydraulic fluid has a density of
~ 0.9 kg/dm³.
This formula applies to straight pipe runs and hydraulic oils. Particularly with regard
to the suction-sided connection, bear in mind that additional screw connections and
pipe bends increase the pressure differential.
Keep the height difference between the pump and the oil level in the tank as low as
possible.
Hoses must be suitable for suction pressures of at least -0.5 bar.
Constrictions in the connections and lines should be avoided. This could
compromise suction output and cause cavitation .
Take note that the nominal size of the connected hoses/piping must be at least as
large as the inlet port sizes.
Make sure that no vibrations or stress/loading from other machinery and equipment
are carried over to filter unit. Use hoses or expansion joints if necessary.
