Structure Optimum Design Of Oil Seal

Finite element method was used to study the sealing mechanism of radial shaft seal. Combining with the sealing theories summed up by the pioneer, the process of finite element analysis was divided into two steps, one step was static analysis, the other step was dynamic analysis.The static analysis of sealing mechanism of oil seal was belonged to contact problem, finite element software ANSYS used in this thesis adopted penalty element method to describe this problem. Based on the characteristic of the structure of oil seal, two-dimensional axisymmetric finite element model of oil seal was established, the finite elements analysis was carried out for the influence of four important parameters on the maximum contact pressure and its distribution which were the width of the waist, the distance between lip surface, the surface of garter spring groove center, the difference in lip and shaft diameter as well as the contact surface angle. The results obtained with this model had established the essential coincidence between computation and practical condition. In dynamic condition, the dynamic sealing mechanism of surface effect and structure effect of the oil seal is used as the theory base, and used a finite element software ANSYS CFX to simulate the flow of sealing medium in the sealing clearance. The difference( A L) between reverse segment and clockwise rotating segment and rotational frequency of the shaft influencing on the reverse pumping brought by the surface effect and the rotational frequency of the shaft influencing on the reverse pumping brought by the structure effect are analyzed. As a result, the reverse pumping brought by surface effect will increase with the increase of A L value and the rotational frequency of the shaft, and the reverse pumping brought by structure effect will increase with the increase of the rotational frequency of the shaft. The simulation result has a well consistency with the experiment result, it proves the feasibility of the finite element method in analyzing the liquid.