So far, the history of the development of gas solenoid valves has been pursued. Gas solenoid valves at home and abroad are divided into three major categories (ie, direct-acting, step-by-step child-guided). The differences in the structure and material of the valve flap and the principle are divided into six subcategories. (Direct acting diaphragm structure, step-by-step diaphragm structure, pilot diaphragm structure, direct-acting piston structure, step-by-step direct-acting piston structure, pilot piston structure)
Direct-acting gas solenoid valve:
Electromagnetic force of the electromagnetic coil lifts the closure from the valve seat. The gas solenoid valve works on electricity. The valve opens; when the power is turned off, the electromagnetic force dissipates, the spring presses the closure on the valve seat, and the valve closes.
However, the diameter is generally not more than 25mm solenoid valve features: vacuum, negative pressure, zero pressure can work properly.
Spread direct-acting gas solenoid valve:
When there is no pressure difference between the inlet and the inlet, the working principle of gas solenoid valve: a principle of direct action and pilot-type combination. After energization, the electromagnetic force directly lifts the pilot small valve and the main valve closure up and the valve opens. When the inlet and outlet reach the starting differential pressure, after the power is turned on, the electromagnetic force pilots the small valve, the pressure in the lower chamber of the main valve rises, and the pressure in the upper chamber falls, thereby pushing the main valve upwards by using the pressure difference; when the power is off, the pilot valve utilizes the spring. Force or medium pressure pushes the closure and moves it down to close the valve.
But the power is larger, and the solenoid valve features: zero pressure difference or vacuum, high pressure can also be * action. Request a required level device.
Pilot type gas solenoid valve:
The gas solenoid valve opens the pilot hole and the gas solenoid valve works: when powered. The pressure in the upper chamber agilely falls, and a pressure difference between the upper and lower parts of the closure is formed. The fluid pressure pushes the closure to move upward and the valve opens. When the power is turned off, the spring force closes the pilot hole and the inlet pressure passes through the bypass hole. A low-to-high differential pressure is formed around the valve closing member, and the fluid pressure pushes the closure member downward to close the valve.
Can be installed (customized) but must meet fluid pressure differential conditions. Solenoid valve features: The upper limit of the fluid pressure range is higher.