The difference between the 3-position 5-way pneumatic solenoid valve in the middle sealing type, the middle relief type and the medium pressure type

The difference between the middle sealing type, the middle leakage type and the medium pressure type of the 3-position 5-way pneumatic solenoid valve is as follows: This picture is the working principle symbol diagram of the middle sealing type, the middle leakage type and the medium pressure type of the solenoid valve.








Middle-sealed type: When both coils are not powered, the pressure in the front and rear chambers of the cylinder remains unchanged at the state after the last coil lost power;the air inlet is closed;the exhaust port is closed. (for a long time In this state, due to small leaks at each connection, this balance will slowly be broken.)






Mid-discharge type: When neither coil is powered, there is no pressure in the front and rear chambers of the cylinder. The air inlet is closed, and the pressure in the front and rear chambers of the cylinder is discharged through the two exhaust ports of the solenoid valve.






Medium pressure type: When neither coil is powered, the pressure in the front and rear chambers of the cylinder remains unchanged at the state after the last coil was powered off, and pressure is continuously supplied to increase the pressure in the front and rear chambers of the cylinder. The pressure is consistent with the air inlet end;the air inlet is open;the exhaust port is closed.






The expressions of ordering codes for 3-position 5-way pneumatic solenoid valves with center sealing type, center relief type and medium pressure type are as shown in Figure 2:









Solenoid valve refers to the use of electric, pneumatic, hydraulic or electromagnetic drive to control the valve by means other than human power. Its characteristics are: easy to use and safe;it can be controlled on-site or remotely;it can control a single solenoid valve or centrally control multiple solenoid valves;it can perform simple switch control or adjust control. ;Cooperated with electronic computer, programmable control can be achieved. Due to the need for remote control, there is usually a solenoid valve signal feedback light signal or 4~20mA signal feedback for valve control. Nowadays, in chemical industry, papermaking, food, medicine, power plants, steel plants, urban and drainage, gas and other departments, due to the need for large-scale precise flow control, valve automation is increasingly used.






Solenoid valves are indispensable fluid control equipment in various sectors of the national economy such as petroleum, chemical industry, power stations, long-distance pipelines, shipbuilding, nuclear industry, various cryogenic projects, aerospace, and marine oil production. After years of development, the number of valve companies in my country ranks first in the world. There are about 6,000 solenoid valve companies of various sizes, of which 900 have an annual output value of more than 5 million yuan. Judging from the product situation, my country's valve industry can currently produce more than a dozen major categories of products, such as solenoid valves, gate valves, globe valves, ball valves, safety valves, check valves, throttle valves, plug valves, pressure reducing valves, and diaphragm valves. , traps, emergency shut-off valves, etc., the maximum operating temperature reaches 570℃, the minimum is -196℃, the maximum pressure is 600MPa, and the maximum diameter reaches 5350 mm.