A solenoid valve is an electromechanical device used for controlling liquid or gas flow.
Parts of the Solenoid Valve
Here are the various parts of the solenoid valve and their working (please refer the figure above).
1) Valve body: This is the body of the valve to which the solenoid valve is connected. The valve is usually connected in the process flow pipeline to control the flow of certain fluid like liquid or air.
2) Inlet port of the valve: This is the port through which the fluid enters inside the automatic valve and from here it can enter into the final process.
3) Outlet port: The fluid that is allowed to pass through the automatic valve leaves the valve through the outlet port.
4) Coil/ Solenoid: This is body of the solenoid coil. The body of the solenoid coil is cylindrical in shape, and it is hollow from inside. The body is covered with steel covering and it has metallic finish. Inside the solenoid valve there is solenoid coil.
5) Coil windings: The solenoid consists of several turns of the wire wound around the ferromagnetic material like steel or iron. The coil forms the shape of the hollow cylinder.
6) Lead wires: These are external connections of the solenoid valve that are connected to the electrical supply. The current is supplied to the solenoid valve from these wires.
7) Plunger or piston: This is the solid round metallic part cylindrical in shape and placed in the hollow portion the solenoid valve.
8) Spring: The plunger moves inside the hollow space due to the action of the magnetic field against the action of the spring.
9) Orifice: The orifice is an important part of the valve though which the fluid is flowing. It is the connection between the inlet and the outlet port.
Thesolenoid valve is controlled by electrical current, which is run through a coil. When the coil is energized, a magnetic field is created, causing a plunger inside the coil to move. Depending on the design of the valve, the plunger will either open or close the valve. When electrical current is removed from the coil, the valve will return to its de-energized state.
In direct-acting solenoid valves, the plunger directly opens and closes an orifice inside the valve. In pilotoperated valves (also called the servo-type), the plunger opens and closes a pilot orifice. The inletline pressure, which is led through the pilot orifice, opens and closes the valve seal.
The most common solenoid valve has two ports: an inlet port and an outlet port. Advanced designs may have three or more ports. Some designs utilize a manifold-type design.