Disadvantages:
1. The sealing performance of pneumatic butterfly valve is poorer than that of pneumatic ball valve and pneumatic valve, so it is used in places where the sealing requirements are not very high;
2. Due to the limitation of the structure and sealing material of pneumatic butterfly valve, it is not suitable for high temperature and high pressure pipeline system. The general working temperature is below 300 ℃ and PN40;
3. The flow adjustment range of the pneumatic butterfly valve is small. When the valve is opened up to 30%, the flow will reach nearly 95%; Under certain working conditions, pneumatic butterfly valves and pneumatic ball valves are not allowed to use valves with diameter shrinkage. On the one hand, it is to reduce the resistance loss of the pipeline, and on the other hand, it is to avoid obstacles to mechanical cleaning of the pipeline after the diameter shrinks.

Those joints are not flexible enough at high temperature, and often cannot be sealed at low temperature. In order to align the interface, it often takes a lot of effort to move the oil dragon forward or backward a little. The pneumatic butterfly valve is bulky, sensitive, and flexible. Even if the oil dragon stops at a wrong position, it can be easily connected. See Fig.
Pneumatic butterfly valves are easy to use, low cost, long life and easy to design. The lowest level pneumatic butterfly valves can be used in this kind of project. Of course, when loading and unloading hydrochloric acid, phosphoric acid, dilute sulfuric acid and other media, the material of the bellows used should request the corresponding anti-corrosion ability. Figure! "Pneumatic butterfly valve for platform liquid loading and unloading
In the process of gasoline loading and unloading, the traditional open loading and unloading,
As for pneumatic butterfly valves recommended for flammable, explosive, highly corrosive and toxic media, even if they are not damaged, they must be replaced or degraded after '(3 to 8) years of operation.