Solenoid valve for water is designed to regulate the flow of liquid. The device works according to the electromechanical principle. For the manufacture of the case, resistant and universal, as well as high-strength materials such as cast iron, brass, and stainless steel are selected. As for membranes and seals, they are made of highly elastic polymers. Among other things, silicone rubber may be included.
A similar device is installed in a part of the piping system that will be easily accessible.
Solenoid valve device
Solenoid valve for water is also called solenoid. It consists of the main parts such as a membrane, housing, spring, cover, stem, as well as an electric coil, which is a solenoid. Valve cover and body are cast in stainless steel, brass, polymer or cast iron. These devices are designed to operate in a wide range of fluids, temperatures and pressures.
Magnetic materials are used for rods and plungers. Electric coils, which are called solenoids, are made in a dust-proof or sealed case. High-quality enameled wire goes to the winding of the coils. It is made from electrical copper. The connection to the piping system can be made using the slate or threaded method. A plug is used to connect to the electrical network. The control is carried out by applying voltage to the coil.
Leading operating positions
If we consider the above-described devices by design, they can be normally closed or normally open. Among the varieties, one can also distinguish bistable valves, which are called impulse. The guiding principle facilitates switching from closed to open position.
Operation principle
The solenoid valve for water can be used under various conditions, this includes the use of direct acting devices, as well as devices that operate at zero pressure drop. On sale you can find valves of indirect action, which are pilot. They only operate at the smallest differential pressure.
Such devices can be divided into three-way dispensing, shut-off and changeover valves.
Information about seals and membranes
Solenoid valve for water contains membranes, which can be made of elasticpolymer materials. The latter have a special design and chemical composition. Among other things, the valves are designed with the latest silicone rubber formulations and other polymers.
Pilot valve principle
A do-it-yourself solenoid valve for water can be installed quickly enough. If we are talking about a normally closed device, then in the static position there is no voltage, while the valve is in the closed state. The piston, which is a shut-off element, is hermetically pressed, it is located at the seat of the sealing surface. The pilot channel is closed. The pressure in the upper chamber is maintained by a bypass in the diaphragm.
This type of valve stays closed until the coil is energized. In order for it to open, voltage must be applied to the coil. Under the influence of a magnetic field, the plunger rises, opening the channel. Due to the fact that the diameter of the channel is much larger than the bypass, the pressure of the upper cavity decreases. The pressure difference acts to lift the piston or diaphragm, which helps open the valve. The water supply solenoid valve will remain open as long as the coil is energized.
Normal open valve principle
Such a device works on the opposite principle: in a static position, the device is open, but when the voltage rises, the valvecloses. In order to keep the device closed, the voltage will be applied to the coil for a long time. In order for any pilot valves to work correctly, a small pressure drop must be maintained.
Such devices are called valves of indirect action for the reason that in addition to applying voltage, it is necessary to fulfill the condition, which is a pressure drop. You can use such a device for heating systems, water supply, hot water supply, as well as pneumatic control. The unit is suitable for those conditions where there is pressure in the pipeline.
Direct acting valve operation
A solenoid valve, the diagram of which makes it possible to understand the principle of operation, can have direct action. Such a device does not have a pilot channel. In the central part there is an elastic membrane, which has a metal ring. Through the spring it is connected to the plunger. When a magnetic field is applied to the coil, the valve opens, the plunger rises and removes force from the diaphragm. The latter rises and contributes to the opening of the valve. At the moment when closing occurs, there is no magnetic field, the plunger descends and acts on the membrane.
No minimum differential pressure is required for this instrument. The solenoid valve, the photo of which is presented in the article, can be used in pressure systems, as well as on drain tanks. You can install the device in conditions of accumulativereceivers. You can mount such a device in places where there is no pressure or is at a minimum level.
Features of the bistable valve
This valve can be in two stable positions: closed and open. Switching is carried out sequentially by applying a pulse to the coil. Such devices operate exclusively from a direct current source. No voltage is required to hold the valve in the closed or open position. By design, such devices are made as pilot ones, which indicates the need for a minimum pressure drop.
The solenoid valve is a reliable and functional fitting for the piping system. If we are talking about special electromagnetic coils, then the resource of their work is very large. Until the moment of failure, the device is able to work until the number of inclusions reaches 1 million. The time it takes for the solenoid valve to operate can range from 30 to 500 milliseconds. The final figure will depend on pressure, diameter and execution.
Conclusion
The device of the solenoid valve was presented above, as well as the principle of its operation. Such devices can be used as a remote control locking device. They are indispensable for safety in the role of shut-off, shut-off and switching solenoid valves. These features must be taken into account before purchasing the valve and installing it in certainconditions.
