Type of solenoid valves

What is Solenoid Valve

A solenoid valve is used to control the flow rate of fluid and gases within a system. A solenoid is an electrically controlled valve and it has two main components

Components of solenoid valve

1. Electric coil with a movable ferromagnetic core (plunger) in it center

2. Valve Body

Working of solenoid valves

When voltage is applied to the coil, the coil produces an electromagnetic field. This electromagnetic field moves the plunger eighter up or down. Which causes the solenoid open or close.

Solenoid valves are normally two types, "Normally Close Solenoid valve " and "Normally Open Solenoid valve"

Types Of Solenoid Valve

1. Direct Acting Solenoid valve

2. Pilot Operated solenoid valve

3. Two-way solenoid valves

4. Three-way solenoid valve

5. Five-way solenoid valve

Direct Acting Solenoid valve

A coil magnetically opens the valve in direct action, lifting the shaft and the seat of the valve without depending on outside pressure.

A direct-acting solenoid valve is Used for small flow rate application and it does not need any outside pressure for it operation. The valve opens by direct action. When voltage is applied to the valve the plunger is pulled up by the electromagnetic field produced by solenoid coils. Which allows the media to pass through.

Pilot Operated solenoid valve

Pilot-operated solenoid valves are also known as indirect acting valves. These valves use the differential pressure of the medium to open and close the valve. These valves provide high flow rates and they operate at high pressure and temperature ranges, with lower power consumption.

In pilot-operated solenoid valves, Solenoid activates a much smaller "pilot" valve that opens up a larger diaphragm, which operates at a much higher pressure and it requires less electrical energy to operate, needs to maintain full power to remain open

Two- Way Solenoid valve

two-way solenoid valves are the most commonly used valves, these solenoid valves have two ports to open or close the fluid flow. It can be either "Normally Open" or "Normally Closed" type. Normally open two-way solenoid valve allows the media to pass through its port when the coil is de-energized and in a Normally Closed valve the media can not pass through its port when the coil is de-energized.

A two-way solenoid valve is used where simply restriction and release of media are needed

Three - Way solenoid valve

The 3 -way solenoid valves come with three ports and it is a commonly used valve. It is used when alternate and exhaustive pressure is required for operation. In three-way valves only two ports can be connected at a time. The three possible setups can be achieved by three-way valves, these setups are

1. Mixing Setup - two inlets and one outlet used

2. Diverting Setup - one inlet and two outlets used

3. Universal Setup - Allows media to flow either direction

Five-way solenoid valve (5/2 and 5/3 solenoid valve)

5/2 and 5/3 solenoid valves are the most commonly used directional control valves for double-acting pneumatic actuators. When de-energized, the single-coil type of 5/2 valve usually has a spring or pilot air return so that the valve returns to its starting function. Dual coil valves do not have this return facility and must be energized to return the valve to its starting position. 5/3 valves have two coils, and if neither is energized, the default state in the center position can be all ports blocked, all ports open, or pressure applied, with the inlet pressure connected to both outlet ports. Manual reset valves necessitate operator intervention in order for the valve to remain operational.