Study of the Influence of the Elastic Rubber Cushion on Product Quality Formed by a Multi - Point Forming (MPF) Process


The Multi-Point Forming (MPF) is an advanced flexible manufacturing technology for three – dimensional sheet metal forming. This is replacing the conventional solid dies by a set of discrete punches called (punch group).This work presents the design and manufacturing of (MPF) dies. It covers also, the effect of using an elastic cushion on the quality of products. This technique eliminates the formation of dimples which, otherwise reduces the quality of product. The work falls into two parts. Part one includes the use of ANSYS, which employs a finite element method (FEM) for the simulation of MPF components, namely: upper jaw, lower die and cushion. In the other part (experimental), a complete MPF die was designed and manufactured in the local market. The copper sheet metal was selected to study the influence of the elastic cushion on the quality of product which formed by MPF process. This rubber was used to avoid the dimples occurring on the metal surface. Experimental and numerical results showedthatthis technique produces a better quality free from dimples. The cushion proved to be effective in elimination of the thickness change. The thickness change was found to be in the range (0-0.05) for a blank of 2 mm.Hence, it is recommended that the (MPF) method is effective in product quality. However, two layers of cushion are necessary to separate between the workpiece and pins to reduce the work piece deformation. Also, the numerical simulation was used by (ANSYS) software which was compared with the experimental result. A good agreement for numerical and experimental results was found.