2、 Common requirements and solutions for pneumatic ball valves To meet different types of pipeline systems, corresponding pipeline systems need to be selected. Table 1 shows the selection principles for common pneumatic components. Table 1 Selection principle of pneumatic components Serial number requirements Solution 1 Common type, in case of failure, valve holding double action pneumatic head, filter pressure reducing valve, solenoid valve, limit switch (through the different connection of solenoid valve and pneumatic head, the opening/closing requirements of the valve can be realized under the power off state)
2 Common type, fault position open/fault position close single acting pneumatic head, filter pressure reducing valve, solenoid valve and limit switch 3 NAMUR compliant structural standard pneumatic head, solenoid valve and limit switch conforming to NAMUR interface shall be selected
4 Manual operation function with pneumatic handwheel or hydraulic hand pump
5 Solenoid valve with manual operation Select solenoid valve with manual function 6 Select filter pressure reducing valve and solenoid valve with large flow for quick opening/closing, increase the diameter of steel pipe, add quick release valve 1 at the air outlet of pneumatic head, and adjust and add regulating valve (needle valve) when solenoid valve controls the opening and closing of 7 valves such as large diameter air control valve Or the damper 8 has no power supply or no power supply on site, and the solenoid valve is replaced by the pneumatic control valve 9. The explosion-proof, waterproof, anti-corrosion, etc. on site use the corresponding level of pneumatic head, solenoid valve, limit switch, connectors, etc. 10 valves/the closing degree can be adjusted. The positioner is used to replace the solenoid valve, limit switch 11. The double acting cylinder realizes the single acting function. The air tank is added Air control valve and other components 12. Copper containing pneumatic components are not allowed on site, such as copper pipes, copper pipe joints, copper solenoid valves 13. Two or more solenoid valves are selected to control the increased reliability of solenoid valves

Reliable valve stem sealing: it has two sealing surfaces, and the sealing surface material of the ball valve is widely made of various plastics, with good sealing performance and complete sealing. It has also been widely used in vacuum systems. Since the valve stem only operates as if it is rotating rather than lifting, the packing seal of the valve stem is not easy to be damaged, and the sealing capacity increases with the increase of the pressure of the medium.