What are the disadvantages of pneumatic butterfly valves?
1. The main valve seat seal ring of pneumatic butterfly valve is made of polytetrafluoroethylene, which is inert to almost all chemicals, has small friction coefficient, stable performance, is not easy to age, has a wide temperature range and strong sealing performance. Perfect performance. However, the physical characteristics of PTFE (including high expansion coefficient, sensitivity to cold flow and poor thermal conductivity) require that the design of valve seat seals should focus on these characteristics.
2. When the sealing material becomes hard, the reliability of the seal will be damaged. In addition, PTFE has a low temperature resistance rating and can only be used at temperatures below 180 ° C. Above this temperature, the sealing material will deteriorate. When long-term use is considered, it can only be used at 120 ° C.
3. Its regulating performance is inferior to that of the stop valve, especially the pneumatic valve (or electric valve).
