Effect of Non-Symmetric Die on Extrusion Process And Product Bending

Abstract

The development in production of curved sections in one forming processusing direct extrusion process is going to increase annually because of increasing demands on such sections that are used in car body construction and railways .This research aims to find a new method for design of non-symmetric dies ,that can extrude a curved product by one pass of extrusion and by controlling the material flow through the deformation zone of the die .The (F.E.M) and (U.B.M) were used indesigning the non-symmetric dies so that the lower and upper die angles are different. The simulation of metal flow during the extrusion process, stresses and strains distribution in the bullet, friction factor and the die angles on the bending or eccentricity of the product were found. The extrusion pressure and the power consumption during the process were also found using both (FEM) and (UBM) methods. The results have shown that :The bend of the product using non-symmetric dies is always towards the small die angle. It has been also shown that the amount of bent or the eccentricity of the product can be predicted from the extrusion parameters. The amount of eccentricity increased with increases of the metal displacement in the dies.