Analysis Of Sealing Performance Of Crankshaft Oil Seal And Study Of Its Influencing Parameters

Crankshaft oil seal is an important part of engine assembly.Its sealing performance directly affects the overall performance of engine.With the development of the automobile industry,the performance of the engine is continuously strengthened,and the speed of the crankshaft is continuously improved,which puts forward more stringent requirements for the sealing performance of the crankshaft oil seal.The traditional structure design of crankshaft oil seal largely depends on the experience of the designer.The sealing performance of crankshaft oil seal can only be obtained by the way of experiment and detection after the product is formed.This development process costs a lot.With the development of computer technology,it has become a new idea to integrate simulation analysis into the structural design and Performance Research of crankshaft oil seal.In this paper,the finite element software ABAQUS is used to build a two-dimensional axisymmetric model of crankshaft oil seal,and the influence of structural parameters of crankshaft oil seal on the static contact performance of crankshaft oil seal is analyzed.The results show that the maximum contact pressure of crankshaft oil seal lip is positively correlated with the lip angle,spring stiffness and waist thickness of oil seal,and negatively correlated with the lip angle,interference and R of oil seal;the radial force per unit circumference of crankshaft oil seal is positively correlated with the changes of interference,spring stiffness and waist thickness of oil seal,and negatively correlated with the changes of lip angle,air lip angle and R of oil seal.Based on the finite element analysis,the optimum structural parameters of crankshaft oil seal are designed with the aid of orthogonal experimental design method,and the optimum combination of structural parameters of crankshaft oil seal is obtained with the maximum contact pressure and the minimum radial force per unit circumference as the optimization objective.Through range analysis,the primary and secondary order of the influence of structural parameters of oil seal on the sealing performance of oil seal is obtained;through variance analysis,the significant degree of the influence of structural parameters of oil seal on the sealing performance of oil seal is obtained.Based on the finite element analysis and the theory of oil seal pumping,the equations of crankshaft oil seal pumping rate and minimum oil film thickness are derived.The influences of oil seal structural parameters,shaft speed and oil temperature on pumping rate and minimum oil film thickness are analyzed.The results show that the minimum oil film thickness is negatively correlated with the changes of oil side lip angle,gas side lip angle,interference,waist thickness and oil temperature,and positively correlated with the changes of R and rotation speed.The suction rate of crankshaft oil seal pump is positively related to the change of lip angle,R and rotation speed on the oil side,and negatively related to the change of lip angle,waist thickness and oil temperature on the gas side.Based on the optimization model of orthogonal test design,the CFD model of temperature field simulation of crankshaft oil seal lip is established,and the influence of oil seal structure parameters,oil temperature and shaft speed on the temperature distribution of oil seal lip is analyzed.The results show that the highest temperature is concentrated in the oil seal lip,the rubber part of the oil seal lip has higher temperature than the surface of the rotating shaft,and most of the heat is released from the surface of the rotating shaft;the highest temperature of the crankshaft oil seal lip is positively related to the change of oil temperature,shaft speed,interference and spring stiffness,and negatively related to the change of air side lip angle.