Authors: BeomSoo Kang WooJin Song TaeWan Ku
Publish Date: 2009/12/05
Volume: 49, Issue: 9-12, Pages: 925-940
Abstract
Multistage deep drawing process is widely used to obtain various nonaxisymmetric rectangular cups This deep drawing scheme including drawing and ironing processes consists of several tool sets to carry out a continuous production within one progressive press To achieve the successive production design and fabrication of the necessary tools such as punch die and other auxiliary devices are critical therefore a series of process parameters play an important role in performing the process design This study focuses on the tool design and modification for developing the rectangular cup with an aspect ratio of 57 using coldrolled low carbon thin steel sheet with the initial thickness of 04 mm Based on the design results for the process and the tools finite element analysis for the multistage deep drawing process is performed with thickness control of the side wall in intermediate blanks as the first approach From the results of the first approach it is shown that the intermediate blanks could experience failures such as tearing wrinkling and earing by excessive thinning and thickening To solve these failures the modifications for the deep drawing punches are carried out and the modified punches are applied to the same process The simulation results for the multistage rectangular deep drawing process are compared with the thickness distributions before and after the punch shape modifications and with the deformed shape in each intermediate blank respectively The results of finite element reanalysis using the modified punches show significant improvement compared with those by using the original designed punch shapes
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