Failure analysis of a double rectangular deep drawn part using fem: An industrial case Conference Paper uri icon

abstract

  • Complex shape deep drawn parts are more frequently used in many industrial applications. However, complex parts can be particularly difficult to form due to serious wrinkling and tearing problems associated to the different forming modes and complex material flow. Moreover, deep drawing depends highly on the part design, including radii, draw depths, wall angles, steps and transitions; these variables interact to affect the cost and quality of the drawing. Since there are not theoretical methods available in the literature yet, and because several factors affect the drawn, deep drawing of complex shapes is usually developed using the trial and error method. To increase the speed of the design process and the machine tuning, and to reduce the use of the trial and error method, computer-assisted analysis and simulations based on numerical approaches such as Finite Element Method (FEM), are more intensively used. By using these computerized methods, process parameters (sheet metal material, lubricants, forces, part geometry etc.) can be reproduced and modified, part defects can be also identified and, if possible, eliminated. This paper presents the analysis of an industrial double rectangular deep drawing kitchen sink using virtual prototyping based on FEM. In the original deep drawing process the part presented defects (cracks). A failure criterion was established to evaluate and reduce the stresses levels that were causing the cracks. An analysis procedure was then proposed and the optimal lubrication conditions were obtained to eliminate the cracks. FEM model, simulations and results, were validated by measuring the thickness of the actual fabricated part. The thickness of the sheet metal at the critical area was measured in the FEM simulation and compared with the thickness profile of the actual fabricated part before and after changes in the lubrication conditions. The results have shown that FEM can be effectively used as a design tool to eliminate part defects in complex shape deep drawing processes. ©2010 by ASME.

publication date

  • 2010-01-01