Finite Element Analysis Of Shrink-Fit Surface In A Wheelset Assembly

The wheelset is one of the most important components in the running gear of locomotive. The contact pressure between axle and hub is not only the important parameter to study fretting damage, but also the important factor to ensure the transmission of torque and resisting relative slip on the fitting surfaces. Therefore, it's important to study the macroscopic stress state on the contact surfaces, and provide the research basis for checking the strength of components and calculating the transmission capacity of connectors.In this paper, take the wheelset structure of K6 bogie truck made by Meishan Rolling Stock Works as the study object, use the finite element software ABAQUS to simulate the shrink fitting process by press-fit method. With the strong post-processing function of ABAQUS, the stress distribution, deformation range and the variation of stresses when assembling can be observed visualized, which has practical significance on the field of engineering.The fitting process of wheelset is simulated respectively by using elastic FEM and elasto-plastic FEM. The stress and strain of every node on the contact surface between axle and hub could be exactly calculated during the assembly, and the region of high stress is also determined. The influence of shrink range on the stress distribution and stress concentration is discussed in detail, and the results indicate that with the increase of shrink range, the stress level of wheel and axle both increased, the stress concentration also become more obvious. By comparing the computing results of two simulation methods, the conclusion is that the elasto-plastic FEM is more significant and valuable than the elastic FEM.Using the elasto-plastic FEM, the influence of hollowness on shrink-fit is studied, then analyzed the distribution of equivalent stress and contact stress and the characteristic of plastic deformation on the contact surface. By comparing the simulating results among solid axle, hollow axle with straight hole and hollow axle with variable hole, the conclusion is that there is no significant difference in results when assembling under the same conditions. The structure of the inner hole has a large influence on the stresses around axle hole, and a small influence on the stresses on contact surface or stress concentration region. So the wheelset with hollow axle is applicable according to the present results.