Analytical and Numerical Investigations of Sheet Metal Bending, Flanging and Hemming PDF Download

Author: Hsien-Chih Wu
Publisher:
ISBN:
Category :
Languages : en
Pages : 316

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Book Description
Quality and preciseness requirements for automobile parts are getting more severe year by year. One of the significant factors to determine a high quality automobile is their appearance. The outer panel surface quality includes the matching quality among press- formed parts and fitting quality which involves the dimensions of uniformity in clearance and level-mismatch between panels. A number of automotive interior and exterior panels are formed by press brake bending or flanging, then joined by hemming. Therefore, the way to get higher quality appearance is to improve press brake technologies. Traditionally the design process for bending, flanging and hemming tools are based on trial-and-error processes and on the skill of experienced die-makers. This approach results in high development cost and long lead-times. Computer simulations are good tools to predict and evaluate the tool and process design. The improvement of computer hardware and software has permitted "virtual" metal forming processes to be conducted on digital computers. Finite element method (FEM) is a numerical procedure for analyzing problems that are too complex to be solved by classical analysis methods. The main objectives of this study are to investigate the flat surface-straight edge, flat surface-contour edge and curved surface-straight edge flanging and hemming processes. Furthermore, The development of new tool design method for flanging and hemming is included. To achieve these goals, numerical models and finite element analysis were performed to compare with experimental data. Besides, industrial flanging and hemming case studies were conducted by commercial FEM package. Consequently, a set of part, process and die design rules and guidelines for bending, flanging and hemming were developed.