Investigation of Sealing Mechanism of Oil Seals Used for Shock Absorbers

Sealing performance of oil seals for reciprocating motion has been previously investigated applying the inverse theory of hydrodynamic lubrication. According to this theory, sealing performance of the oil seal is dominated by factors such as the configuration of the lip (lip angle), viscosity of the fluid to be sealed, the sliding speed and the physical property of the lip material. In this presentation, the authors apply the above mentioned theory to a shock absorber seal under the condition where the pumping stroke and motoring stroke speeds of the rod are different. Consequently, the configuration of the seal lip is improved.