1 Scheme for machining the inner surface of pneumatic ball valve shell The inner surface of shell parts can be machined by turning, milling, grinding and other methods. In order to process the shell of the pneumatic ball valve shown in Figure 1, the two inner surfaces of the ball were milled separately with a forming milling cutter before, but the machining accuracy failed to meet the requirements. Therefore, the processing of this part is listed as a scientific research topic in the university.)

Structural features of pneumatic butterfly valve: pneumatic butterfly valve is generally composed of bellows, mesh sleeve and joint. Bellows are the body of pneumatic butterfly valve, playing a flexible role; The net sleeve has the effect of strengthening and shielding; The joint plays the role of connection. For different application requirements, they have different ways of connecting with each other: bellows, mesh sleeves and joints are connected by welding, which is called welding type; The connection by mechanical clamping is called mechanical clamping; In addition, the combination of the above two methods is called hybrid.
Installation of pneumatic butterfly valve:
1. Install the pneumatic butterfly valve in the right direction, or it will crack quickly and have a long service life.
2. The hose can be installed either horizontally or vertically or obliquely. The most ideal state is to install the hose vertically. The hose should not be installed near the wheel. If necessary, a baffle can be installed.
3. Generally, pneumatic butterfly valves can be divided into three lengths: the first is the tightening length, that is, the length when the hose is tightened to the limit position; The second is the installation length, which is the length of the hose when it is in the central position of half of the maximum displacement; The third is the stretching length, which is the length when the hose is stretched to the maximum limit.
4. When installing the hose, the hose should be in the central position. Under this position, the hose can move in two directions when it is subjected to axial load. Otherwise, if it can only move in one direction, the strength of the pneumatic butterfly valve will be affected and the service life will be reduced.
5. In the process of theoretical installation, considering that using a ruler to measure the length of the hose according to the calculation results and then stopping the installation may affect the production power, some foreign manufacturers directly install the ruler on the hose and cut off the ruler after installation.
Application of pneumatic butterfly valve on mechanical equipment