What is a solenoid valve and how does it work?

A solenoid valve is an electrical valve with an integrated solenoid. It uses electromagnetic force to control the flow of fluids in industrial processes and other applications. A solenoid valve is a type of fluid control valve that uses electro-mechanical principles to open or close ports on demand. They are either normally closed or normally open valves, but not both at once. Solenoid valves are differentiated by the way electricity powers them: continuous current vs. alternating current, as well as NC (normally closed) vs. NO (normally open) configurations. Here we discuss types, functions, operating principle and applications of a solenoid valve in detail.

Types of solenoid valves

There are four main types of solenoid valves : Normally closed (NC), Normally open (NO), Selective and Remotely controlled valves. The Normally Closed (NC) solenoid valve is the valve that’s normally closed. It’s either closed or open (in rare circumstances it could be partially open). The Normally Open (NO) solenoid valve, as the name suggests, is normally open. It’s either closed or open (in rare circumstances it could be partially open). The Selective solenoid valve is a two-way valve that can be turned on and off manually. Usually, the operator will turn it off and on using a toggle switch. Remotely controlled valves feature an electric mechanism that can be operated from a remote location.

Function of a Solenoid Valve

A solenoid valve is an electromagnetic valve. It consists of a solenoid that controls the flow of fluid. It is used for isolating pressure, controlling flow, and for starting and stopping a flow. The solenoid is operated by an electromagnet, controlled by an electrical current. Liquid flows through the valve when the solenoid is energized. The operation of a solenoid valve is based on the principle that a high-voltage electrical current flowing through a soft iron core will create a magnetic field and be attracted to a metal armature. The metal armature is an electromagnet that controls the flow of liquid through a port. The solenoid valve is either normally open or normally closed, but not both at the same time. Normally open valves are opened by an electrical current. Normally closed valves are closed by an electrical current.

Operating Principle of a Solenoid Valve

A solenoid valve consists of a solenoid, a valve body and a valve spool. The solenoid is a closed cylindrical coil wrapped around an iron core. The valve spool is an axially movable cylindrical plug that is fitted inside the valve body. When a current passes through the solenoid it creates an electromagnetic force which attracts the spool. This allows the flow of fluid through the port that is used to connect the inlet to the valve. When the current is switched off, the spool falls back to its original position, which closes the port.

Applications of Solenoid Valves

Solenoid valves are used for controlling the flow of gases, liquids, and minerals. They can also be used for switching an electrical circuit on or off. These applications can be found in industrial sectors such as oil & gas, chemical, food & beverage, and power generation. Solenoid valves are used in a wide variety of industries and applications. They are used in fluid control, heating and cooling systems, power transmission, waste water treatment, and more. Solenoid valves are also used for pressure control, with the ability to modulate pressure in a wide range. They are also energy efficient with low power consumption. Since they are electromagnetic valves that require electricity to function, they are used in applications where electrical power is available.