At present, the sealing material required for the manufacture of oil seal is made of synthetic rubber. Since the choice of sealing material and structural design are the main factors that affect the sealing performance and service life of the oil seal, the performance of the rubber is properly controlled to properly select the rubber sealing material Very important. Which rubber should be chosen as the most suitable for the oil seal material? This should be determined by the relevant parameters of the oil seal, ie the radial force on the shaft should be high enough to prevent the oil seal from leaking to maintain a certain film thickness to maintain a low friction Heat; oil seal should have enough interference to overcome the impact of the use of eccentricity; lip in the contact area is one of the determinants of the area. The oil seal material directly affects the above three parameters, because the material changes with time and temperature, the key parameters also change, such as: with the temperature increases, the material modulus decreases, so that the sealing material radial force changes. Thermal expansion, sealing media caused by the swelling of the material, the hardness of the compound, etc. affect the radial force and interference.

For the above reasons, in the choice of oil seal material to consider the following characteristics: oil seal material and sealing medium compatible, oil seal material is not due to sealing media swelling, hardening and so on; oil seal material has good heat resistance, wear resistance ; Oil seal material with moderate elasticity, can adapt to the shaft roughness and eccentricity changes.

Due to the changes in the formulation of the rubber seal material, the new sealing material is constantly present and the existing sealing material is continuously improved. For the current production of oil seals are the most commonly used nitrile rubber, polypropylene rubber, silicone rubber, fluorine rubber and polytetrafluoroethylene.