Mounting the filter housing
MRFD1
en(us)
Page 25 / 44
MoWa MRFD1 4113517a en-us 2016-08-10.docx
2016-08-10
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:
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 fluid has a
density of ≈
0.9 kg/cm³.
This formula applies to straight pipe runs and hydraulic oils. Additional threaded
connections and pipe bends increase the pressure differential.
Keep the height difference between the filter housing and the oil level in the
tank as low as possible.
Take note that hoses must be suitable for 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 stresses or vibrations are transmitted to the filter housing.
Use hoses or expansion joints if necessary.
