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.

Brief Analysis on Color Selection of Stainless Steel Pneumatic Butterfly Valve with Good Quality
If you want to purchase a good pneumatic butterfly valve, you should consider the comprehensive factors of the pneumatic butterfly valve, the medium characteristics of the pneumatic butterfly valve, the natural conditions of its installation site, the size of the pipe diameter of the pneumatic butterfly valve, the maximum displacement and other factors.
The flexible body of pneumatic butterfly valve is divided into annular bellows flexible body and spiral bellows flexible body. In order to compensate displacement, installation tendency and foundation settlement, absorb vibration and reduce noise, annular bellows pneumatic butterfly valve should be selected; For places with high pressure but infrequent displacement and vibration, spiral bellows pneumatic butterfly valve should be selected. The nominal pressure of pneumatic butterfly valve refers to the maximum working pressure available at room temperature.
I'm afraid the stainless steel products that everyone first came into contact with were stainless steel tableware. We all know that their color is bright. Some flat stainless steel can almost be used as mirrors.
So is the color of all stainless steel products bright? Neither.
Some customers think that the color of stainless steel pneumatic butterfly valve should be relatively bright. In fact, we will find that some kinds of stainless steel pneumatic butterfly valves are snow-white or even dark silver gray.
For example, 316L stainless steel bellows is not bright in snow white color.
It was once thought that the bright color of 304 stainless steel pneumatic butterfly valve was the way to distinguish 304 from 201 pneumatic butterfly valve made of ordinary materials.
Later, I learned that some 201 pneumatic butterfly valves are also very bright in color, while some 304 pneumatic butterfly valves are very dark in color.
In fact, the bright color of stainless steel pneumatic butterfly valves is mainly due to the use of electroplating or polishing, while some 304 stainless steel pneumatic butterfly valves will reduce their luster due to the manufacturing process, such as the use of acid pickling, but the acid and alkali resistance will not be affected.