Oil seal is used to seal grease (oil is the most common liquid substance in the transmission system, also refers to the general meaning of the liquid substance) mechanical components, it will need to lubricate the transmission parts and the force parts isolation, not to let the lubrication ber leakage, its rotary oil seal (dynamic seal) or automotive oil seal (shaft motion seal) are due to the different requirements of the use of conditions, determine the oil seal to choose the rubber oil seal Seal material performance and requirements, the current commonly used rubber sealing materials include nitrile rubber, acrylate rubber and fluorine rubber, in addition we can also choose to use polyurethane, silicone rubber, hydrogenated butyl rubber, polytetrafluoroethylene and other parts of the industry commonly used rubber sealing materials. this article focuses on nitrile, fluorine rubber, silicone and hydrogenated nitrile these four materials.