Through the analysis of the sectional drawing of the pneumatic ball valve shell, the most ideal method for machining the inner surface of the part is turning. Because it is difficult to ensure the dimensional accuracy and surface quality of spherical surface by manual turning with ordinary lathe, it is difficult to achieve good surface contact when matching with other parts, so CNC turning must be adopted to ensure the processing accuracy. Since the inner surface of the valve body is approximately a closed sphere, it is inconvenient for the tool to enter and exit during machining. If the ordinary wok cutter is used for processing, it is difficult to ensure its rigidity because the overhang length of the cutter bar exceeds 75mm. Therefore, reasonable tool design is the key step to realize machining.

The flow coefficient adjustment butterfly valve of the analysis and regulation butterfly valve is also called the ventilation butterfly valve, which belongs to a kind of butterfly valve. It is mainly used for gas pipeline systems in metallurgy, mining, cement, chemical industry and power generation industries as flow regulating equipment. The valve is mainly composed of valve body, valve disc and driving device. Its basic principle is that the drive device drives the valve plate to open at any angle between 0~90 °, so as to control the flow of medium in the pipeline when flowing through the valve body