HYDAC International MRF 2 NU, Инструкция по эксплуатации и техническому обслуживанию

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MRF 2 NU MultiRheo Filter
3.1.1 Remarks Pertaining to Piping / Tubing
The number of screwed fittings used is to be kept to a minimum so as to minimize pressure
loss.
The pressure loss in a hydraulic line is dependent on the following factors:
•
Flow rate
•
Kinematic viscosity
•
Line dimensions
•
Density of medium
It can be approximated for hydraulic oils as follows:
ρ υ
× × × × ≈ ∆
Q
d
L
bar p
4
8 . 6 ] [
L = line length [m]
d = inside line diameter [mm]
Q = volumetric flow rate [l/min]
ϑ = kinematic viscosity [mm²/s]
ρ = density [kg/dm³] of mineral oil
≈ 0.9 kg/dm³
This applies to level piping and the use of hydraulic oil grades. Additional screwed fittings
and pipe bends result in an increase in the pressure differential.
The difference in the elevation of the filter unit in relation to the oil level should be kept as
small as possible.
The hoses have to be suitable for a minimum pressure of -0.5 bar and the maximum
operating pressure of the filter housing.
Bottlenecks or narrow places in the connecting lines are to be avoided as the flow rate is
reduced and a cavitation hazard is posed.
The nominal width of the connecting line must correspond at minimum to the cross-sections
of the connector threads or the connector flange.
HYDAC Filtertechnik GmbH
en
Page 12
BeWa MRF2NU 3341025 en.doc 2007-09-24