Function And Use; Functional Description - Siemens SK... Operating Instruction

4

Function and Use

4.1

Functional Description

The following functions are done by two spring loaded diaphragms:
a) Pressure holding function
Protection against sucking empty at under pressure or empty lifting due to creation of an
artificial counter pressure.
Fig. 4.1
b) Overpressure function
Protection against impermissible overpressure in the metering line (adjustable opening
pressure).
Fig. 4.2
c) Vent function
Suction aid for first-time startup of the pump.
Fig. 4.3
d) Emptying function
Emptying and therefore relief of the pressure line at machine standstill.
Fig. 4.4
417101382_MFV_II-III.doc
In normal operation a diaphragm valve must be
pressed against a preset spring pressure of 1
bar for passage to the metering line by the
delivery pressure of the metering pump.
If the counter pressure in the metering line rises
above a spring pressure set at the multifunction
valve (see chapter 5.3
overpressure function), a diaphragm valve
opens and delivery into the bypass takes place.
By turning knob 2 to the right (pressure relief
valve) the metering counter pressure is relieved.
If the knob is turned by more than
NOTE
approx. 20°, the knob snaps back to
the initial position.
The metering line is emptied by turning the two
knobs 1 and 2.
If the two knobs are turned by more
NOTE
than approx. 20°, they snap back to
the initial position.
- 18 -
Setting opening pressure
Rev: 5-02/10