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Direct-acting solenoid valve and direct-acting solenoid valve

How the solenoid valve works
Solenoid valve is an automatic basic element used to control the direction of the fluid, belonging to the actuator; usually used for mechanical control and industrial valves, to control the direction of the media, so as to achieve the control of the valve switch. There are closed chambers in the solenoid valve. There are through holes in different positions. Each hole leads to a different tubing. The valve is in the middle of the chamber. Two electromagnets are on both sides. Which side of the magnet coil energizes the valve body. On which side, by controlling the movement of the valve body to block or leak out different oil discharge holes, and the oil inlet hole is normally open, the hydraulic oil will enter different oil discharge pipes, and then push the pressure of the oil to push the oil tank. Pistons, pistons also drive the piston rod, the piston rod drives the mechanical device. This controls the mechanical motion by controlling the electromagnet current. Only the electromagnetic valve is used to act on the iron core sealed in the magnetic isolation sleeve of the electric control valve, there is no dynamic seal, so the leakage is easy to block. Electric valve torque control is not easy, easy to produce internal leakage, and even break the stem head; the structure of the solenoid valve is easy to control the internal leakage until it is reduced to zero. Therefore, the solenoid valve is particularly safe to use, especially for corrosive, toxic or high-low temperature media. The solenoid valve itself has a simple structure and a low price, and is easier to install and maintain than other types of actuators such as regulating valves. What is even more remarkable is that the self-contained system is much simpler and the price is much lower. Because the solenoid valve is a switch signal control, it is very convenient to connect with the industrial control computer. In today's era of widespread computer availability and sharply lower prices, the advantages of solenoid valves are even more pronounced.

Solenoid valve type
1. Direct acting solenoid valve:
Principle: When the power is turned on, the electromagnetic coil generates an electromagnetic force to lift the closing member from the valve seat and the valve opens. When the power is turned off, the electromagnetic force disappears. The spring presses the closing member against the valve seat and the valve closes.
Features: It can work normally under vacuum, negative pressure and zero pressure, but the diameter generally does not exceed 25mm.
2、Distribution direct acting electromagnetic valve:
Principle: It is a combination of direct acting and pilot type. When there is no pressure difference between the inlet and the outlet, the electromagnetic force directly lifts the pilot small valve and the main valve closing part and the valve opens. When the inlet and outlet reach the starting differential pressure, after the power is turned on, the electromagnetic force leads the small valve, the pressure in the lower chamber of the main valve rises, and the pressure in the upper chamber decreases, thereby pushing the main valve upwards by utilizing the pressure difference; when the power is off, the pilot valve utilizes the spring. Force or medium pressure pushes the closure and moves it downwards to close the valve.
Features: It can also operate at zero differential pressure or vacuum or high pressure, but it requires a large amount of power and must be installed horizontally.
3, pilot solenoid valve:
Principle: When the power is turned on, the electromagnetic force opens the pilot hole, the pressure in the upper chamber drops rapidly, and a pressure difference between the lower part and the upper part is formed around the closing part. The fluid pressure pushes the closing part to move upwards and the valve opens; when the power is turned off, the spring force leads the pilot. The hole is closed and the inlet pressure quickly bypasses the chamber to form a lower, upper high pressure differential around the valve closing member. The fluid pressure pushes the closing member downward and closes the valve.
Features: The upper limit of the fluid pressure range is high and can be installed arbitrarily (customization is required) but the fluid pressure difference must be met. Solenoid valve is divided into six sub-categories from the difference in principle and valve structure and material: direct-acting diaphragm structure, step-by-step structure, pilot diaphragm structure, direct-acting piston structure, step-by-step direct motion Piston structure, pilot piston structure.

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