Pneumatic ball valve, with its well-known characteristics, is widely used in various pipeline systems for quick cut-off, changing the flow direction of media and automatic control. It can be driven manually, electrically or pneumatically. Figure 1 shows the typical structure of pneumatic ball valve (driving mode is not considered). Fig. 1 In the service performance of pneumatic ball valve, sealing is one of its main indicators. It can be seen from Figure 1 that the sealing structure of the pneumatic ball valve is mainly composed of three parts, one of which is the sealing between the main valve body and the auxiliary valve body, which is realized by the sealing adjusting gasket; The second is the seal between the main valve body and the valve stem, which is based on the standard; The outer sealing structure of the pneumatic ball valve is formed by means of the T-shaped packing or the 0-shaped sealing ring. The third is the seal between the ball and the main and auxiliary valve bodies, which is realized by the seal seat and forms the main sealing structure of the pneumatic ball valve. The tightness of the main sealing structure affects the working performance of the pneumatic ball valve, and is the key sealing structure in the design and manufacture of the pneumatic ball valve. This paper will focus on the non-metallic seal (also called soft seal) structure of the main seal of the pneumatic ball valve.

Fluoroplastic composite metal shrink joint compensator. In view of the lack of metal and non-metallic composite material products with good processability and strong applicability for the pipeline compensator used to resist severe corrosion, a method for preparing the fluoroplastic composite metal shrink joint was designed,
The fluoroplastic composite metal shrink joint uses austenitic stainless steel as the base material, stops the high-pressure sand blasting of particles on the surface of the base material to make it support the surface of the porous micro pit, then immerses the surface of the porous micro pit with fluoroplastic of the same thickness, stops the high-temperature solidification of the surface of the supported fluoroplastic composite metal, and finally adopts the hydraulic forming technology to form the bellows in one overall way, Fluoroplastic composite metal shrink joints have high strength and ductility of metal materials, and good corrosion resistance and oxidation resistance. The preparation process is relatively simple and easy to implement. The inner liner and base material have been separated firmly and evenly. The working medium and application conditions of fluoroplastic composite metal shrink joints meet the relevant rules, It is a replacement product for ordinary austenitic stainless steel metal contraction joint. Product characteristics of fluoroplastic metal compensator