Screening-based evidence of the impact of geometrical deviations on inner stresses on mechanical presses

作     者：N. Wagner T. Päßler 

作者机构：Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Straße 88 09126 Chemnitz Germany 

出 版 物：《Procedia Manufacturing》 

年 卷 期：2019年第27卷

页      面：185-191页

主　　题：Press Tolerancing Residual stress 

摘      要：In recent years various cases of damage analysis have shown an increasing number of overload scenarios resulting in failures of entire press structures. This happens in spite of manufacture-compliant utilization and a correct press design process based on state-of-the-art methods such as FEM simulation. This paper proves the hypothesis that geometrical tolerances, defined clearances and geometrical signs of wear have a significant impact on residual stress of a press, by conducting an empirical sensitivity analysis. The focus is on mechanical presses with four-point leverage actuation as an example for highly over-determined press structures. As proven by FEM simulation, the identified geometrical deviations result in a preload of the press structure, amounting up to 10% of its theoretical sustainable stress. The significant impact of geometrical deviations on the residual stress has been proven successfully for the empirically determined assumption.