5. Design and manufacture of pneumatic ball valve The application of CAD, CAM and FMS in the valve industry has brought the design and manufacture of pneumatic ball valve to a new level. Not only has the design and calculation method of valves been comprehensively innovated, but also the heavy and repetitive routine design work of professional technicians has been alleviated, so that technicians have more energy to improve and improve product performance and new product development, shorten the research and development cycle of new products, and comprehensively improve labor productivity, Due to the application of CAD/CAM, the valve stem spiral flat, which is produced by computer aided design and computer aided numerical control machine tools, has emerged, making the metal sealed pneumatic ball valve free of any scratch and wear during the opening and closing process, thus greatly improving the sealing performance and service life of the pneumatic ball valve. When the pneumatic ball valve is fully opened, the flow resistance is very small, almost equal to zero. Therefore, the equal diameter pneumatic ball valve is widely used in oil and gas pipelines because it is easy to clean pipelines. Since the ball of the pneumatic ball valve is wiping in the opening and closing process, most pneumatic ball valves can be used in the medium with suspended solid particles, and the materials based on the sealing ring can also be used in the powder and granular medium.

6. Two types of pneumatic control valve FC
A: The air source enters the lower chamber of the membrane chamber, the spring is located in the upper chamber of the membrane chamber, the valve core is installed, and the valve is opened after air intake.
B: The air source enters the upper chamber of the membrane chamber, the spring is located in the lower chamber of the membrane chamber, the valve core is reversely installed, and the valve is opened after air intake.
It is worth mentioning that, at present, the inner structure of the valve body in most cases adopts the positive installation of the valve core.