Since the polytetrafluoroethylene (PTFE) having a high corrosion resistance, stable, easy to aging, low friction coefficient, easily shaped, dimensionally stable, and can be filled by addition of a suitable material to improve the overall performance, to give better strength, friction The butterfly valve sealing material with a lower coefficient overcomes the limitations of synthetic rubber. Therefore, a macromolecular polymer material represented by PTFE and its filling and modifying materials have been widely applied to butterfly valves, thereby enabling the performance of the butterfly valve. It has been further improved to create a butterfly valve with a wider temperature and pressure range, reliable sealing performance and longer service life.