The rubber sealing ring is an annular cover composed of one or several parts, which is fixed on a ferrule or gasket of the bearing and contacts with another ferrule or gasket or forms a narrow labyrinth gap to prevent lubricating oil from leaking and foreign objects from invading. Sealing, sealing, buffering, etc. Products made of various materials such as fluorine rubber, butyl rubber, silica gel, ethylene-propylene rubber, difluoro rubber, etc. have excellent mechanical properties, good electrical properties and good permeability. They are widely used in various machines and are resistant to various petroleum-based oils and various chemical media. The temperature range of -60 ℃ ~ 200 ℃ (difluoro rubber FFKM can reach more than 300 degrees through specific vulcanization method) and the operating pressure range is:<10MPa (hydraulic),<1MPa (pneumatic)<16MPa (static seal) Ding Qing rubber and gasoline resistant (90,93,97) expansion rate is 0.