2way Servoassisted
With larger orifices the static pressure increases and it is necessary that the magnetic field produced by the coil is able to control these force.
This is achivied by using the servoassisted action in the solenoid valve. |
Normally Closed
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The Normally Closed design has an inlet and an outlet connection into the body valve. When the coil isn’t energised the flow is blocked by the main seal which can be a diaphragm or a piston. In this mode the media flows through a small hole in the diaphragm (or piston) and helps to close the valve. When the coil is energised the pilot orifice opens allowing the media above the main seal to exhaust and the main valve seal to open.(this type of valves needs a minimum differential pressure to work)
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Normally Open
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In this design the media pressure helps to keep the main valve seal open.
When the coil isn’t energised the flow is uninterrupted by the main seal which could be a diaphragm or a piston design. In this mode the media flows through a small hole in the diaphragm (or piston) and helps to open the valve. When the coil is energised the pilot orifice closes allowing the media above the seal to pressurise and to the main valve seal to close. (this type of valves needs a minimum differential pressure to work)
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Assisted lift diaphragm
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With these models the armature is mechanically attached to the diaphragms controlling the central pilot orifice and the stroke of the main seal.
This design allows the valves to work at zero differential pressure. |