The solenoid valve may be defined as an electromechanical valve which can be use with the liquids as well as gases. As the name suggests, here the valve is controlled by the supply of electric current via a solenoid coil. Solenoid valves usually have two or more number of ports. So in a two port solenoid valve, the flow can be switched either on or off. But in case of a three port valve, there is one port for inwards flow of fluid and two ports for outflow.

The solenoid valves are the most extensively used flow control elements in the fluid mechanics. This is because of their widespread applications. They can shut off, release, distribute or combine fluids in a pipeline. Other advantages of these valves may include, speed, safety in switching, extreme reliability, good compatibility with the other materials and low power requirements. The solenoid valve can be used with different kinds of actuators like plunger type actuators and pivoted armature actuators.

Working of solenoid valve

The solenoid valve is made up of two parts and they are the solenoid and valve. First, the solenoid is used for the conversion of electrical energy in to mechanical energy and it helps in the mechanical processes of closing and opening of the valve. The valve has only a small flow circuit. The solenoid valves may sometimes have seals made up of metal or rubber and also may have electrical interfaces in order to assist in easy control.

The working of the solenoid valve relies entirely on the pressure difference between the input and output. As long as the pressure at the input is larger than the pressure at the output, it will work properly. If the pressure in the output increases above that of the input, the valve will be opened irrespective of the position of the pilot valve or the solenoid.

The solenoid valves are usually used in the various pneumatic systems for the purpose of controlling cylinders and huge industrial valves as well. Another significant use of the solenoid valves is in the automatic irrigation sprinklers.