Finite Element Analysis of the Influence of Chamfer Hub Geometry on the Stress Concentrations of Shrink Fits

The theoretical expressions commonly used in the design of interference fits do not take into account the huge stress concentrations located at the edges of the hub. This underestimation of the real stress state can induce the incorrect performance of the shaft–hub assembly. Among the different methods to address this problem is the use of chamfer hubs, which are used for reducing such stress concentrations. In this paper, an analysis, performed via finite element method, of the influence of the geometric parameters of a shrink fit with chamfer hubs was carried out with the aim of determining the optimal dimensions for the design of this type of mechanical assembly. To achieve this goal, different chamfer hub geometries were considered: (i) full–chamfer hubs defined by the chamfer angle and (ii) partial–chamfer hubs defined by the chamfer angle and the chamfer height. According to the obtained results, stress concentrations can be reduced by using a full–chamfer hub with chamfer angles within the range 13°–15° depending on the hub thickness. In addition, similar results can be obtained by using partial–chamfer hubs with a chamfer height of half of the hub thickness and chamfer angles within the range 13°–15°. By using these design recommendations, the theoretical equations can be used without underestimating the real stress state.