Festo VZWM, Operating Instructions Manual

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VZWM
Festo VZWM 0612NH English
19
2 F u n c tion
The VZWM diaphragm valve is a 2/2−way shutoff valve for air, water or neutral
liquids. In the basic position the diaphragm valve is closed. The input pressure is
effective on a diaphragm and seals the valve seat. In order that this function can
be guaranteed, the difference in pressure p between the input (connection P)
and the output (connection A) depending on size amounts to at least 0.5 bar and
must always be available.
The difference in pressure results from the ratio of the following flow rate to the
nominal size and must not be too low.
By means of a pilot control a bypass is opened from the input to the output. The
pressure on the diaphragm is reduced and the liquid medium flows through the
valve.
When current is applied to a suitable solenoid coil mounted on the plunger tube,
the valve opens. As soon as the current circuit on the solenoid coil is interrupted,
the valve closes.
3 Appli ca tion
The VZWM diaphragm valve has been designed for opening and closing rigid
tubing connections through which one of the above−mentioned liquid media flows.
Ple as e note
Do not use the diaphragm valve in closed systems, as a continuously available
difference in pressure cannot be guaranteed in these cases.
4 Tr a n s port a n d s tor ag e
S
Take into account the weight of the VZWM diaphragm valve: depending on
size, it can weigh up to 4.0 kg.
S
Ensure the following storage conditions:
storage time:
short
storage location: cool, dry, shaded and protected against corrosion.