What are the principles and structures of solenoid valves?

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. While rankings may vary depending on time and market conditions, the following brands are generally considered to be among the top brands in the valve industry:

The following influential first-line brands of water system valves and industrial valves can be used as a reference, but for reference only: Suzhou Neway Valve, Shanghai Guanlong Valve, Shanghai Qizhong Valve, Sanhua, Su Yan, Shentong, Su Valve, Nanfang, Jiang.

First, the word Yao. The above manufacturers are only estimates and references, and the specific situation may vary or fluctuate at any time due to changes in a series of factors such as changes in the market, the size of the competition pattern, and the stability of product quality. As an indispensable key device in industrial production and civil facilities, the quality and reputation of the valve brand directly affect the satisfaction and trust of users.

These brands are known in the valve industry for their innovative technology, high-quality products and reliability. It is important to note that the market and industry are evolving rapidly, and different rankings may vary depending on time and region. For the most up-to-date ranking information, it is recommended to refer to industry reports, professional organizations or market research data for more detailed and accurate information.

Piston, pilot, direct-acting, etc.

(1) Principle of direct-acting solenoid valve: when energized, the solenoid coil generates electromagnetic force to lift the closing part from the valve seat and open the valve; When the power is off, the electromagnetic force disappears, the spring force presses the shut-off on the valve seat, and the valve closes. Features:

It can work normally under vacuum, negative pressure and zero pressure, but the general diameter does not exceed 25mm.

2) Principle of step-by-step direct-acting solenoid valve: it is a combination of direct-acting and pilot-operated principle, when the pressure difference between the inlet and outlet, when energized, the electromagnetic force directly lifts the pilot valve and the main valve closure up in turn, and the valve opens. When the pressure difference between the inlet and the outlet, when the power is on, the electromagnetic force first opens the pilot small valve, the pressure in the lower chamber of the main valve rises, and the pressure in the upper chamber decreases, so as to use the pressure difference to push the main valve upward; When the power is off, the pilot valve and the main valve use the spring force or medium pressure to push the shut-off and move down to close the valve.

Features: It can also work reliably at zero pressure difference or vacuum and high pressure, but the power is large and requires vertical installation.

3) Pilot solenoid valve principle: when energized, the electromagnetic force opens the pilot hole, the pressure of the upper chamber drops rapidly, and a low and high pressure difference is formed around the closing piece, which pushes the closing part to move up and the valve opens; When the power is off, the spring force closes the pilot hole, and the inlet pressure quickly enters the upper chamber through the bypass hole, forming a low and high pressure difference around the closing valve, pushing the closing part to move down and closing the valve. Features:

The upper limit of the fluid pressure range is high, but the differential fluid pressure condition must be met.

Solenoid valve is an industrial equipment controlled by solenoids, and it is a basic element of automation used to control fluids.

Its working principle is: there is a closed cavity in the solenoid valve, there are through holes in different positions, each hole is connected to a different oil pipe, the middle of the cavity is a piston, two sides are two electromagnets, which side of the magnet coil energized valve body will be attracted to which side, by controlling the movement of the valve body to open or close different oil drain holes, and the oil inlet hole is normally open, the hydraulic oil will enter different oil drain pipes, and then push the piston of the oil cylinder through the pressure of the oil, the piston drives the piston rod, and the piston rod drives the mechanical device. In this way, by controlling the current interruption of the electromagnet, the mechanical movement is controlled.

<> tracing the development history of solenoid valves, so far, solenoid valves at home and abroad are divided into three categories in principle (namely: direct-acting, step-by-step child pilot-operated type), and from the difference in valve disc structure and material and the difference in principle, it is divided into six sub-categories (direct-acting diaphragm structure, step-by-step heavy film structure, pilot diaphragm structure, direct-acting piston structure, step-by-step direct-acting piston structure, pilot piston structure).

Direct-acting solenoid valve.

Principle: When energized, the electromagnetic coil generates electromagnetic force to lift the closing part from the valve seat, and the valve opens; When the power is off, the electromagnetic force disappears, the spring presses the closing part on the valve seat, and the valve is closed with a ballast.

Features: In vacuum, negative pressure, zero pressure can work normally, but the diameter is generally not more than 25mm.

Distributed direct-acting solenoid valves.

Principle: It is a combination of direct and pilot principle, when there is no pressure difference between the inlet and the outlet, after the power is on, the electromagnetic force directly lifts the pilot valve and the main valve closure up in turn, and the valve opens. When the inlet and outlet reach the starting pressure difference, after the power is applied, the pressure of the lower chamber of the electromagnetic pilot valve and the main valve rises, and the pressure of the upper chamber decreases, so as to use the pressure difference to push the main valve upward; When the power is off, the pilot valve uses the spring force or medium pressure to push the shut-off and move down to close the valve.

Features: It can also operate reliably when there is zero pressure difference or vacuum and high pressure, but the power is large, and it must be installed horizontally.

Pilot operated solenoid valve.

Principle: When energized, the electromagnetic force opens the pilot hole, the pressure of the upper chamber drops rapidly, and a low and high pressure difference is formed around the closing piece, and the fluid pressure pushes the closing part to move upward, and the valve is opened; When the power is off, the spring force closes the pilot hole, and the inlet pressure quickly forms a low and high pressure difference around the closing valve through the bypass hole, and the fluid pressure pushes the closing part to move down and close the valve.

Working principle: the solenoid valve contains a closed cavity, the middle of the cavity is a piston, and the two sides of the cavity are two electromagnets, once the solenoid coil is energized, the valve body is attracted to the direction of the energized electromagnet by force; There are through holes at different positions in the cavity and different oil pipes are connected, so the part of the oil drain hole can be selected by controlling the movement of the valve body.

Since the oil inlet hole is in the normally open state, the movement of the valve body causes the hydraulic oil to enter different oil discharge pipes, and the pressure of the oil pushes the piston of the cylinder, which in turn pushes the piston rod, thereby driving the mechanical device. Using this principle, it is possible to control the movement of the machine by controlling the current and disconnection of the electromagnet.

Solenoid valve, English name is electromagneticvalue, is a kind of automation basic components used to control fluids, often used in industrial control systems, to adjust the direction, flow, speed and other parameters of the medium, solenoid valve has the characteristics of high precision, good flexibility, many models, wide use and so on. Solenoid valves can be divided into many types, and different solenoid valves can play their role in different positions of the control system.

Solenoid valves contain a variety of classification methods, which can be divided into water solenoid valves, high-pressure solenoid valves, fire solenoid valves, etc., according to the different valve structures, materials, etc., and can also be divided into six types, such as direct-acting diaphragm structure, pilot diaphragm structure, and distributed direct-acting piston structure. However, one of the most important classification methods of solenoid valves is to classify them according to their principles, which can be divided into three types: direct-acting solenoid valves, step-by-step direct-acting solenoid valves, and pilot-operated solenoid valves.

The working principle and function of the solenoid valve, the direct-acting solenoid valve. Principle: When the normally closed type is energized, the electromagnetic coil generates electromagnetic force to lift the open part from the valve seat, and the valve is disassembled; When the power is off, the electromagnetic force disappears, the spring presses the opening part on the valve seat, and the valve is open.

The normally open type is the opposite. Features: It can work normally under vacuum, negative pressure and zero pressure, but the diameter is generally not more than 25mm.

Step-by-step direct-acting solenoid valve. Principle: It is a combination of direct-acting and pilot-operated principle, when there is no pressure difference between the inlet and the outlet, after the power is on, the electromagnetic annihilation force directly lifts the pilot valve and the main valve closure up in turn, and the valve opens.

When the entrance and exit. Features: It can also operate when there is zero pressure difference or vacuum and high pressure, but the power is large, and it must be installed horizontally.