Solenoid valves are types of valves, usually electrically controlled, used to ensure the passage of fluid substances such as air, gas, water, and hydraulics through pipelines.

The English and correct version of the concept also referred to as "selenoid" is solenoid. Inside the valves controlled by the winding coil opening the valve with pilot air or by applying electricity, there is usually a spring system. This spring system ensures that the valve closes again when there is no electricity or pilot air.

Solenoid valves, used in a wide variety of areas such as pneumatic, hydraulic, and gas systems, can be used in two different variations as normally open or normally closed. For example, if it is desired for the fluid to pass through the valve continuously under normal conditions but you want the valve to close when you wish, it would be more logical to use a normally open solenoid valve.