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The uncertainties in the auto body stamping process affect the stamping quality significantly. The current stamping simulation and optimization may lead to design failure without considering these uncertainties. A systematic stamping robust design approach is proposed. The variation behavior of the local auto sheet properties is analyzed, and the parameters are obtained. A stochastic analysis method is developed, where FE-simulation, uniform design, response surface methodology (RSM) and Monte-Carlo simulation are used. The robust optimization model composed of mean and standard deviation is constructed and solved. The proposed approach is verified through feature box and deck lid inner panel forming process. The developed approach offers rapid and reliable results for engineers to deal with potential stamping problems during the early phase of product and tooling design, saving more time and resources. [ABSTRACT FROM AUTHOR]

Sheet metal forming is a displacement or draw-in controlled manufacturing process in which a flat blank is drawn into die cavity to form an automotive body panel. Draw-in amount is the single most important stamping manufacturing index that controls all forming characteristics (strains, stresses, thinning, etc.), stamping failures (splits, wrinkles, surface distortion, etc.) and line die operations and automations. Draw-in Map is engineered for math-based die developments via advanced stamping simulation technology. Then the Draw-in Map is provided to die makers in plants as a road map for math-guided die tryout in which the die tryout workers follow the engineered tryout conditions and matches the engineered draw-in amount so that the tryout time and cost are greatly reduced, and quality is ensured. The Map can also be used as a math-based trouble-shooting tool to identify the causes of formability problems in stamping production. The engineered Draw-in Map has been applied to all draw die tryout for all GM vehicle programs since 1998. A minimum 50% reduction in both lead-time and cost and significant improvement in panel quality in tryout have been reported. This paper presents the concept and process to apply the engineered Draw-in Map in die tryout. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Upon unloading after the forming stage, a sheet metal product will spring back due to internal stresses. Springback is a major problem for process-planning engineers. In industrial practise, deformations due to springback are compensated manually, by doing extensive measurements on prototype parts, and altering the tool geometry by hand. This is a time consuming and costly operation. In this paper the application of two compensation algorithms, based on the finite element simulation of the forming process are discussed. The smooth displacement adjustment (SDA) method and the springforward (SF) method have been applied to several industrial products, such as the NUMISHEET 2005 benchmark[sharp/mesh/hash_synonym]1. With the SDA method successful compensations have been carried out. For the SF method some principal problems remain. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]