Solenoid Valve Construction Terminology
Bleed-Orifice or Bleed Hole - Small orifice or channel, most often located in the diaphragm or piston of pilot-operated valves, to allow the inlet flow to pressurize the top side of the diaphragm or piston.
Bonnet - Screwed plug or bolted cover on the valve body, on which the core tube with inner parts is fitted.
Coil - Electrical part of the valve consisting of a spool wound with insulated copper wire, which creates a magnetic flux when energized.
Core - A soft magnetic stainless steel part of the solenoid, which is moved by magnetic forces (flux generated by coil).
Core Spring - Spring, which returns the core to the original position when the coil is de-energized.
Core Tube - Stainless steel tube, closed at one end, which isolates the media in the value from external solenoid parts.
Disc/Valve Disc - Sealing material on the core or disc-holder, which shuts off the seal orifice.
Disc-Holder - Valve part, actuated by the core, in which a sealing disk is inserted.
Main Orifice - Principle passage between inlet and outlet of the value