MP Filtri ICM, Руководство пользователя

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Hydraulic Connection 49
hose. The required differential pressure can be obtained by taking advantage of
an existing pressure drop within the system. Alternatively one can be created by
inserting a check valve. The ICM can then be connected across this differential
pressure source.
15.1.2 Detailed Calculations
In general the flow rate of fluid through the ICM needs to be kept within the range
of the unit (see hydraulic specification 3.2). The ICM measures the flow during
operation, so this can be used to check that the flow is correct.
A flow that is out of range will be indicated by a fault code (see 16.1).
Results taken with out-of-range flows are not logged.
The flow is entirely generated by the differential pressure between the ends of the
pipes used to connect the ICM. The pressure needed to generate an in-range flow
can be estimated by assuming a target flow, and determining the resulting pressure
drop across the ICM and connection piping. Use Figure 15.4 on page 51 to lookup
the ICM pressure drop, and manufacturers data to lookup the piping pressure drop
at the desired flow. The sum of these two pressures is the pressure needed.
The user connects the ICM between two points in the hydraulic circuit, that have
this pressure difference.
In order to use the graph:
•
Determine the working viscosity of the fluid, e.g. 30 cSt.
•
Decide on a desired flow rate. 200ml/minute is normally used since this is in
the middle of the ICM flow range. But 100ml/minute is also suitable and uses
less oil.
•
Use the graph 15.4 to look up the pressure drop, across the ICM ports, at this
flow rate and viscosity. E.g. at 30cSt and 200ml/minute, this is 0.4 Bar. The
maximum and minimum allowed differential pressures can also be determined
using the 400ml/min and 20ml/min lines, respectively.
•
Determine the additional pressure drop caused by the piping used to connect the
ICM. This may be negligible for 1/4 inch piping and over, but is very important