Computer Aided Design of “Multi-Holed”, Streamlined Extrusion Dies

Concepts for computer aided design of single-holed, streamlined extrusion dies are now well developed, and these have been presented in the CIRP,' 1980 and 1982 annals. Based on these concepts a powerful and user-friendly software package known as ‘STREAM’ has been developed, and is capable of designing streamlined (and other shaped) dies for arbitrary product sections. The potential advantage of the use of streamlined dies in producing defect-free extrusions has been demonstrated – particularly for P/M alloys, with and without fiber reinforcements. However, these new design concepts were limited to single-holed dies, and presented a serious shortcoming in their potential applications in industry – particularly in aluminum alloy extrusions. This paper presents new concepts developed for the design of multi-holed, streamlined (and other shaped) dies. A user-friendly software package has been developed for the design of rotational symmetric, multi-holed dies for arbitrary product sections. Results obtained with 4-hole and 6-hole streamlined dies are presented.