Electromagnetic diaphragm valve is a special structure of direct acting or pilot operated solenoid valve. It uses electromagnetic force as a power source to open or close fluid channels by controlling the up and down movement of a diaphragm (a flexible film).
The core design feature is to use a flexible diaphragm to completely isolate the flow channel inside the valve body from the upper electromagnetic drive mechanism and valve chamber. This makes it particularly suitable for situations that require strict sealing, prevent cross contamination, or handle high viscosity, particle laden fluids.
2、 Main components
Electromagnetic coil: After being powered on, it generates a magnetic field that attracts the movement of the iron core (valve core) and is the power source of the valve.
Valve body: Connected to the pipeline, it is the channel for fluid flow.
Diaphragm: Core component. It is usually made of elastic materials such as rubber, fluororubber, polytetrafluoroethylene, etc., which serve to isolate and seal.
Valve seat: The diaphragm is pressed onto it to achieve sealing.
Spring: When the electromagnetic coil is powered off, it resets the diaphragm and closes or opens the valve (depending on the normally open/normally closed design).
3、 Working principle
Electromagnetic diaphragm valves are mainly divided into two types based on their operating modes: direct acting and pilot operated.
1. Direct acting electromagnetic diaphragm valve
Working principle: When the coil is energized, the electromagnetic force directly lifts the valve core upwards, and the valve core then directly pulls up the diaphragm, opening the flow channel. When the power is cut off, the spring force pushes the valve core downwards, pressing the diaphragm tightly against the valve seat and closing the flow channel.
Characteristics: The structure is relatively simple, with no requirements for fluid pressure (even applicable to vacuum state), but usually has a small diameter and high power consumption of the electromagnetic coil.