Most butterfly valves that appeared in the early years used natural rubber seats. Although they have excellent sealing performance, they apply to low temperatures and pressure, generally around 70 ℃, not greater than PN10. Later, the appearance of synthetic rubber and its application in butterfly valves raised the applicable temperature to about 120 ℃, and the pressure increased to PN16. The corrosion resistance and wear resistance have been greatly improved, and are still widely used in the water supply and drainage industry today.
With the rapid development of the chemical industry and the emergence of fluoroplastics, the performance of butterfly valves has further improved.
The PTFE butterfly valve seat is used to raise the applicable temperature of the butterfly valve to 180 ℃, and the applied pressure is also greatly improved, and it is resistant to strong acids and strong Corrosion of alkali and chemical solvents.
