A solenoid valve constitutes an electromechanical device designed to regulate the flow of fluids or gases within a pipe or a tube. It belongs to a category of valves that utilize a solenoid for controlling the valve's opening and closing actions.
The solenoid itself is an electromagnetic coil capable of generating a magnetic field upon the passage of an electric current through it. This magnetic field is then harnessed to either open or close the valve. There are diverse types of solenoid valves, and among them, the pilot operated solenoid valve is the focal point of this article.
What Exactly is a Pilot Operated Solenoid Valve?
A pilot operated solenoid valve is a specific type of valve that employs a pilot valve to manage the opening and closing of the main valve. The pilot valve is a relatively smaller valve that is under the control of the solenoid.
When the solenoid is energized, it triggers the opening of the pilot valve, which subsequently leads to the opening of the main valve. Conversely, when the solenoid is de-energized, the pilot valve shuts, and as a result, the main valve also closes.
Design and Operation of a Pilot Operated Solenoid Valve
Typically, a pilot operated solenoid valve encompasses a valve body, a main valve, a pilot valve, a solenoid, and a spring.
The valve body serves as the outer casing of the valve and houses the other components. The main valve, being the larger one, governs the flow of the fluid or gas. The pilot valve, which is smaller in size, is responsible for controlling the opening and closing of the main valve.
The solenoid, an electromagnetic coil, exercises control over the pilot valve. Meanwhile, the spring is utilized to maintain the main valve in a closed state when there is no pressure present.
When the solenoid is energized, it generates a magnetic field that pulls the plunger of the pilot valve, thereby opening it. This enables the fluid or gas to flow through the pilot valve, which in turn prompts the opening of the main valve. Subsequently, the fluid or gas flows through the main valve and exits the valve body.
When the solenoid is de-energized, the magnetic field dissipates, and the spring then pushes the plunger of the pilot valve back to its original position, closing the pilot valve. This, in turn, causes the main valve to close as well, halting the flow of the fluid or gas.
