Tuesday 19 June 2012

How Does a Two-way Solenoid Valve Work

Overview of Two-Way Solenoid Valves
A Two-Way Solenoid Valve is an electromechanical valve controlled by an electric current. The electric current runs through a solenoid, which is a wire coil wrapped around a metallic core. A solenoid creates a controlled magnetic field when an electrical current is passed through it. This magnetic field affects the state of the solenoid valve, causing the valve to open or close. Two-Way Solenoid Valves are used to transport gases or liquids and have a wide variety of applications, including irrigation, sprinkler systems and industrial uses. Two-Way Solenoid Valves allow substances to be transported in either direction within the valve, making them extremely versatile and useful for industrial applications.
Mechanics of a Two-Way Solenoid Valve
The mechanical force in a Two-Way Solenoid Valve is the solenoid coil, which converts electrical energy into magnetic energy that is used to modulate the valve. A Two-Way Solenoid Valve contains an inlet pipe, which transports the gas or liquid into the solenoid valve. The valve consists of a rubber or plastic stopper that is held against the inlet pipe to seal it closed. The front end of the stopper contains a rubber O-ring, which seals the inlet pipe and prevents the gas or liquid from entering the Two-Way Solenoid Valve. The stopper is held in place by a metallic spring attached to the back end of the stopper. The stopper is also attached to a metallic pin via a metal bar that runs perpendicular from the pin to the stopper. The pin is located near the solenoid coil. When the solenoid coil is activated, the magnetic field draws the pin back, which pulls the stopper back and breaks the seal with the inlet pipe, allowing the gas or liquid to enter the Two-Way Solenoid Valve. When the solenoid coil is deactivated, the force of the spring pushes the stopper back into place against the inlet pipe. Two-Way Solenoid Valves contain solenoid coils and stoppers at either end of the valve in order to facilitate the movement of the substance in either direction. The inlet and outlet pipes are interchangeable in a Two-Way Solenoid Valve since each pipe can take in or expel the substance.
Importance of Pressure in Two-Way Solenoid Valves
Two-Way Solenoid Valves are different from pumps in that there is no mechanical device to force the liquid or gas through the valve. As a result, it is important for a Two-Way Solenoid Valve to have a pressure differential between the outlet pipe and the inlet pipe. Specifically, the inlet pipe must have higher pressure than the outlet pipe to force the gas or liquid through the Two-Way Solenoid Valve. Equalized pressure within a Two-Way Solenoid Valve will prevent a substance from flowing though the valve, regardless of the state of the solenoid and the stopper. Two-Way Solenoid Valves are capable of easily changing the pressure differential between the two ends of the valve in order to regulate the direction of flow through the valve.