Fundamentals of process design for dimensionally accurate roll forming of asymmetrical profile geometries

非对称型材几何形状的尺寸精确滚压成型的工艺设计基础

• 批准号: 407937637
• 负责人: Professor Dr.-Ing. Peter Groche
• 金额: --
• 依托单位: Institut für Produktionstechnik und Umformmaschinen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407937637?language=en
• 关键词: Fundamentals; process; design; dimensionally; accurate

Roll forming is a continuous manufacturing process for cold rolled profiles, which sees use besides others in the automotive and furniture industry. In contrast to discontinuous bending methods, like die bending, the sheet metal is formed in a three-dimensional forming process. Besides the bending of the cross section additional process-related deformations happen which lead to profile defects. Especially asymmetrical profiles are always subjected to torsion and multi-dimensional bowing.Nowadays, the use of Finite-Element-Simulations during the process design is the only way to detect the profile defects. Due to the time intensive calculations the application of FEM-simulations is limited. Furthermore, the interactions between process parameters and profile defects are not fully understood, so the process design is mainly empirical and the resulting profile defects have to be compensated in time-consuming correction processes.The project aims at the prediction, analysis and reduction of the defects after roll forming of an asymmetrical hat profile. The asymmetrical hat profile is suited best, because it can represent complex profile geometries with several bending zones. Within the project the process design will be improved in two ways. On the one side, an analytical model for the prediction of torsion of asymmetrical hat profiles, without the necessity of FEM-simulations, is developed to be used as the initial value for the numerical optimization. On the other side, numerical and experimental investigations of roll forming of asymmetrical hat profiles are conducted to characterize and analyse the process-related additional deformations, the resulting profile defects as well as the influence of process parameters of the roll forming process. Based on the results, effective counter measures can be deduced and numerically investigated. Following the investigation, the counter measure found most effective, is optimized by an optimization algorithm coupled with the FEM-simulations. Thereby, the parameters of the counter measures are optimized with regard to a balanced state of strains within the profile. Finally, the counter measure and the optimization algorithm are validated experimentally.By deepening the understanding of the creation of profile defects of complex profile geometries, the developing of effective counter measures and the development of an analytical model to predict torsion in the early design stage, this project contributes to an more accurate and efficient process design with the aim to significantly shorten correction processes and to increase the production rate.

滚动形成是冷滚动轮廓的连续制造过程，除了在汽车和家具行业中使用的其他配置文件外，还可以使用。与不连续的弯曲方法（如模具弯曲）相反，钣金以三维形成过程形成。除了横截面的弯曲外，还会发生其他与过程相关的变形，从而导致轮廓缺陷。尤其是不对称的剖面总是经受扭转和多维鞠躬。如今，在过程设计中使用有限元模拟是检测轮廓缺陷的唯一方法。由于时间密集型计算，FEM模拟的应用受到限制。此外，过程参数与轮廓缺陷之间的相互作用尚不完全了解，因此过程设计主要是经验性的，并且必须在耗时的校正过程中补偿所得的轮廓缺陷。不对称帽子轮廓的卷后缺陷。不对称的帽子轮廓最适合，因为它可以用几个弯曲区域代表复杂的曲线几何形状。在项目中，过程设计将通过两种方式进行改进。一方面，开发了一种用于预测不对称帽子剖面扭转的分析模型，而无需进行FEM模拟，将其用作数值优化的初始值。另一方面，进行了不对称帽子轮廓的滚动形成的数值和实验研究，以表征和分析与过程相关的额外变形，所得的轮廓缺陷以及滚动形成过程的过程参数的影响。基于结果，可以推导并进行数值研究。在研究之后，发现最有效的计数器是通过与FEM模拟的优化算法优化的。因此，根据轮廓内的菌株平衡状态，对计数器测量的参数进行了优化。最后，通过实验验证了计数器测量和优化算法。通过加深对复杂剖面几何形状的概况缺陷的理解，有效的计数器的发展以及开发分析模型以预测早期设计阶段的扭转，该项目有助于更准确，更有效的过程设计，目的是大大缩短校正过程并提高生产率。