HYDAC FILTER SYSTEMS CSM-E, Инструкция по установке и обслуживанию

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Making the hydraulic connections to the unit
Notes on pipes/hosing
Use as few threaded connections as possible in order to keep the pressure
loss as low 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:
Δp ≈ 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 oil has a density
of approx. 0.9 kg/dm³.
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 used must be suitable for suction pressures of at least -0.5 bar.
Avoid constrictions in the connected hoses. This reduces the delivery action
and increases the risk of cavitation.
The nominal size of the supply lines must be at least as large as the nominal
width of the connecting line of the power unit in order to prevent excessively
high pressure loss.
Make sure that no vibrations or stress/loading are carried over to the pump
by fastening the tubes. Mount hoses or expansion joints if necessary.
CSM-E en(us) Page 27 / 64
MoWa CSM-E 3911629a en-us 2017-12-11.docx 2017-12-11