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http://dx.doi.org/10.5228/KSPP.2009.18.7.538

A Study on Development of Combined Drawing Process for Automotive Cowl Cross Bar with Variable Diameters  

Kim, H.S. (대구대학교 자동차.산업.기계공학부)
Youn, J.W. (대구대학교 자동차.산업.기계공학부)
Publication Information
Transactions of Materials Processing / v.18, no.7, 2009 , pp. 538-543 More about this Journal
Abstract
The cowl cross bar of an automobile is a frame component that is installed inside the cockpit module to provide a guide surface, to which functional components for electricity and air condition are attached. In the recent years, the geometries of cowl cross bars are getting more complex in order to meet the demands of a wide variety of embedded functional components and the reduced weight of frame parts with enhanced mechanical and noise/vibration characteristics. There for, welding processes between tubes with different diameters are widely conducted while the welded parts are experiencing various problems such as undermined appearance, low production efficiency and poor mechanical characteristics. Therefore, this paper seeks to develop an one-piece forming process which eliminate welding process for the cowl cross bar by applying the tube drawing process. However, it was predicted that a conventional tube drawing can not be applied directly to the current part since the area reduction ratio of the drawing process reaches 51.7% which exceeds the general limiting value. Therefore, in this study, a combined drawing process which adds a compressive force to a tensile force of the conventional drawing process was proposed and 2-stage drawing process was designed by using CAE analyses. In addition, drawing tryouts were carried out by using the manufactured combined drawing machine in order to verify the designed process.
Keywords
Cowl Cross Bar; Combined Drawing Process; Process Sequence Design; Drawing Tryout;
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  • Reference
1 I. S. Um, S. M. Na, Y. G. Kim, H. S. Kim, D. S. Park, 2007, Optimal application of automotive cowl cross bar using hydroforming technology, Proc. Kor. Soc. Mech. Eng. Conf., pp. 13-18
2 K. Swiatkowski, R. Hatalak, 2004, Study of the new floating-plug drawing process of thin-walled tubes, J. Mater. Process. Technol., Vol. 151, pp. 105-114   DOI   ScienceOn
3 T. Kuboki, K. Nishida, T. Sakaki, M. Murata, 2008, Effect of plug on leveling of residual stress in tube drawing, J. Mater. Process. Technol., Vol. 204, pp. 162- 168   DOI   ScienceOn
4 S. W. Kim, Y. N. Kwon, Y. S. Lee, J. H. Lee, 2007, Design of mandrel in tube drawing process for automotive steering input shaft, J. Mater. Process. Technol., Vol. 187-188, pp. 182-186   DOI   ScienceOn
5 National Machinery Company, 1981, National Forging Talks, Tiffin, Ohio
6 D. H. Kim, D. J. Kim, B. M. Kim, 1998, Process design of multi-step wire drawing using artificial neural network, Trans. Mater. Process., Vol. 7, No. 2, pp. 127-138
7 M. Cog, T. Altan, 2001, An overall review of the tube hydroforming(THF) technology, J. Mater. Process. Technol., Vol. 108, pp. 384-393   DOI   ScienceOn