HYDAC FILTER SYSTEMS CMP 1321, Operating And Maintenance Instructions Manual

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CMP Hydraulic connection of the CMP
HYDAC FILTER SYSTEMS GMBH en(us) Page 20 / 36
BeWa CMP1321 3765034 en 2012-09-25.doc 2012-09-25
Notes on pipes and hoses
In order to keep the pressure loss as low as possible, use as few threaded
connections as possible.
The pressure loss in a hydraulic line depends upon:

Flow rate

Kinematic 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 = pipe length [m]
d = internal pipe 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/cm³.
This applies to straight pipe runs and hydraulic oils. Additional threaded connections
and pipe bends increase the pressure differential.
Keep the height difference between the unit 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 .
Note that the nominal size of the connected hoses/piping must be at least as large
as the cross-section of the INLET connection.
Make sure that no tension or vibrations are carried over to the pump or filter housing
when the pipes are connected. Use hoses or expansion joints if necessary.