| Wheels are essential drive parts of vehicles, whose quality has a direct impact on automobile performance and safety. Tubeless steel wheels are widely used in commercial vehicles, because of low production cost and strong bearing capacity. During practical service condition, wheels commonly break due to fatigue failure. Hence, it is very significant for wheels design and manufacturing engineering to predict wheels’ fatigue life precisely. In addition, among the process of wheels manufacturing, the spoke spinning process is the key process related to wheels product quality. Therefore, research on wheel fatigue performance and spoke spinning process has great value for both theoretical study and engineering application.In this paper, wheel bending fatigue tests were carried out on several types of steel wheels, to measure their fatigue life and identify the initial location of fatigue cracks. Based on software ANSYS Workbench, FEM models of bending fatigue test and cornering fatigue test were built. Through FEM analysis, the stress distribution of wheels was studied, especially for the stress-strain state and the stress cycle of vent holes.Based on FEM analysis results of wheel fatigue tests, methods to applying fatigue analysis software Fe-safe in wheels fatigue life predictions were studied. Several different fatigue life algorithms and mean stress correction methods were used to predict wheels fatigue life.In comparison with tests result, the most accurate fatigue life algorithm was identified. It was critical plan methods that led to smaller prediction errors than nominal stress method and local stress-strain method. The prediction errors of critical plan methods is 12.7%, while the prediction errors of nominal stress method and local stress-strain method is around 147%.Through comparative study on two steel wheels of same type with different spoke shapes, the influence of spoke shapes on stress level and fatigue life was studied. Based on software Optistruct, methods to applying topological optimization technology in spoke shapes was studied. In use of the SIMP method, the spoke shape was optimized and the optimal load transfer path in spoke was revealed. The optimization was targeted to lightweight design under bending fatigue loads and cornering fatigue loads, with the maximum stress constrained,Based on FEM software ABAQUS, the modeling method of spoke spinning process was studied, which improved the computing efficiency. According to the features of software ABAQUS, by replacing the rotation of blank with revolution of rollers, the mass scaling factor could be setting up with a larger number while the harmful effect of virtual inertia force on simulation results was avoided. In this way, the iteration increment was increased and the computation time was reduced. Compared with traditional model, the new model reduce the computation time by more than 85%, which added more practical value to FEM analysis technology. The material flow, wall thickness variation, stress-strain field during spoke spinning process was studied through FEM analysis. By means of experiments design, the influence of rollers feed path and axial distance on final shaping quality was studied and rollers feed path and axial distance were optimized... |
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