Solenoid valve is an electromagnetic control of industrial equipment, is used to control the flow of the automation of the basic components, belong to the actuator, not limited to hydraulic, pneumatic. The direction, flow rate, speed and other parameters of the media are adjusted in the industrial control system. Solenoid valve can be combined with different circuits to achieve the expected control, and control accuracy and flexibility can be guaranteed. There are many kinds of solenoid valve, different solenoid valve in the control system in different positions to play a role, the most commonly used is one-way valve, safety valve, directional control valve, speed regulating valve and so on.

Main classification of solenoid valve

1, solenoid valve from the principle of divided into three categories:

1 Direct-Action solenoid valve:

Principle: When energized, the electromagnetic coil generates magnetic force to lift the closing part from the seat, the valve opens, the electric force disappears, the spring closes the piece on the seat, and the valve closes.

Features: In the vacuum, negative pressure, 0 pressure can work normally, but the path is generally not more than 25mm.

2-Step Direct Action solenoid valve:

Principle: It is a direct and pilot-type combination of the principle, when the inlet and outlet no pressure difference, after the electricity, electromagnetic force directly to the pilot small valve and the main valve closed in turn up, the valve opened. When the inlet and outlet reach the starting pressure difference, after the electricity, the electromagnetic force pilot small valve, the main valve lower chamber pressure rises, the upper chamber pressure drop, thereby using the pressure differential to push the main valve upward; When the power is off, the pilot valve uses the spring force or the medium pressure to push the closing parts, move downward and make the valve close.

Features: in 0 pressure differential or vacuum, high pressure can also be * action, but the power is large, requirements must be installed horizontally.

3 Pilot type solenoid valve:

Principle: When energized, the electromagnetic force opens the pilot hole and the upper chamber pressure drops rapidly, in the closure around the formation of a low pressure differential, fluid pressure to push the closing piece upward movement, valve open, power off, the spring force to the pilot hole closed, the inlet pressure through the bypass hole rapid chamber in the closed valve parts around the formation of low high pressure differential, Fluid pressure pushes the closing piece downward and closes the valve.

Characteristics: The upper limit of fluid pressure range is high, can be installed arbitrarily (need to be customized) but must satisfy the fluid pressure difference condition.

2, solenoid valve from the valve structure and material differences and the principle of the difference, divided into six branches of small categories: direct motion diaphragm structure, step-by-step direct motion diaphragm structure, the pilot diaphragm structure, direct motion piston structure, step-by-step direct piston structure, the pilot piston structure.

3, solenoid valve according to function classification: water solenoid valve, steam solenoid valve, refrigeration solenoid valve, low-temperature solenoid valve, gas solenoid valve, fire solenoid valve, ammonia solenoid valve, gas solenoid valve, LIQUID solenoid valve, micro solenoid valve, pulse solenoid valve, hydraulic solenoid valve often open solenoid valve, oil solenoid valve, DC solenoid valve, high-pressure solenoid valve, Explosion-proof solenoid valve.