Reverse engineering of casting equipment for process simulation

In this work a procedure to obtain the three-dimensional CAD model of a casting from the physical equipment is proposed. In fact, the actual geometry of the cast part cannot be used for process simulation because of the shrinkage and deformation occurring during the casting process. The procedure is based on reverse engineering tools and involves four steps: pre-digitizing, digitizing, surfaces reconstruction, and three-dimensional CAD modelling. Critical issues are identified and discussed in this paper. To verify this procedure, it is applied to an aeronautical part fabricated by sand casting. Results prove that this RE approach is adequate to virtually reconstruct the single geometry of each equipment part and of the whole assembled mould. The three-dimensional CAD model is demonstrated to be suitable for CAE analysis, leading to a finite element mesh that meets requirements of casting simulation. Furthermore it is easily editable to adapt the design according to numerical outputs.