FAM 15/30 ATEX
Connecting the FAM
HYDAC FILTER SYSTEMS GMBH
en(us)
Page 33 / 84
BeWa FAM15_30 Atex 3197970c en-us 2012-08-08.doc
2012-08-08
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 differential in a hydraulic line (
P
(line)
) depends on the following:
Flow
rate
kinematic
viscosity
Pipe
dimensions
Fluid
density
The pressure loss in straight pipes (
P
(line)
) can be calculated 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/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 pump and the oil level in the tank as minimal
as possible.
Hoses must be suitable for suction pressures of at least -0.5 bar.
Avoid constrictions in connecting pipelines because they reduce output and increase
the risk of cavitation.
The nominal size of the connected hoses/piping must be at least as large as the
inlet port sizes in order to prevent an excessively high negative suction pressure.
