DG - 10/2019
http://www.end.de
15
Description of Function
Fig. 4.4 - description of function - normally closed with the flow direction
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Normally close with the flow direction
The in neutral position closed valve obtains this function by a spring, which acts in close direction.
By feeding with compressed air the pilot pressure moves the piston against the spring and lift up
the valve disk from the seat. Therefore the valves open.
Because the valve closes with the flow direction, the nominal pressure supports the closing pro-
cess and seals the valve disk against the seat additionally. If the media flows through the valve with
a high speed the valve could close to fast and this could causes pressure shocks in the pipes.
The electrical control signal will be changed into the pressure media control by an optional avai-
lable solenoid valve. The figure 4.3 shows a directly mounted solenoid valve type MGAG3D.
Fig. 4.3 - description of function (Options: optical position indicator, solenoid vavle)
valve closed
valve opend by
compressed air
valve closing by
spring force
© END-Armaturen GmbH & Co. KG
Содержание DF3D
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