Hardware Knowledge Hall: Classification characteristics and working principles of solenoid valves

So far, trace the development history of gas solenoid valves. The gas solenoid valves at home and abroad are divided into three categories in principle (ie: direct-acting, step-by-step pilot-operated), and are divided into six sub-categories from the difference in valve structure and material and the difference in principle. (Direct-acting diaphragm structure, step-by-step heavy-piece structure, pilot diaphragm structure, direct-acting piston structure, step-by-step direct-acting piston structure, pilot piston structure)

Direct-acting gas solenoid valve:

The electromagnetic force of the solenoid coil lifts the closing part from the valve seat. The working principle of the gas solenoid valve is when it is energized. The valve opens; when the power is cut off, the electromagnetic force dissipates, the spring presses the closing piece on the valve seat, and the valve is closed.

But the diameter of the solenoid valve is generally not more than 25mm. Features: It can work normally under vacuum, negative pressure and zero pressure.

Distributed direct-acting gas solenoid valve:

When there is no pressure difference between the inlet and the inlet, the working principle of the gas solenoid valve: a principle of combining direct-acting and pilot-operating. After being energized, the electromagnetic force directly lifts the pilot small valve and the main valve closure piece upwards in turn, and the valve opens. When the inlet and outlet reach the starting pressure difference, after power 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 drops, so that the pressure difference pushes the main valve upward; when the power is off, the pilot valve uses a spring The force or medium pressure pushes the closing piece and moves downward to close the valve.

But the power is larger, and the solenoid valve features: it can be operated under zero pressure difference, vacuum or high pressure. Request required level device.

Pilot-operated gas solenoid valve:

The gas solenoid valve opens the pilot hole. The working principle of the gas solenoid valve is when it is energized. The pressure in the upper chamber drops quickly, and a high pressure difference is formed around the closure member. The fluid pressure pushes the closure member upward and the valve opens; when the power is off, the spring force closes the pilot hole, and the inlet pressure passes through the bypass hole in the agile chamber. A pressure difference is formed around the valve closing member, and the fluid pressure pushes the closing member to move downward to close the valve.

Can be installed arbitrarily (customization required) but must meet the fluid pressure differential conditions. Solenoid valve characteristics: the upper limit of the fluid pressure category is higher.