Analysis of Cold Extrusion of Non Re-entry Product Shapes

Abstract

The paper presents a feature-based analysis of cold extrusion process for non re-entry shapes. Part drawing of the shape to be extruded is drawn using line, arc, circle, polyline and ellipse entities of AutoCAD R-12 and corresponding DXF file is created. Treating shape as a feature, DXF file is processed and necessary data are separated for feature recognition. An upper-bound model for design of non re-entry cold extrudable shapes is proposed. The concept is then used to compare various die profiles based on the consideration of total extrusion power. It is found that third order stream-line and cosine dies are the best among various profiles considered. Parametric study for a square section using a third order polynomial die profile is carried out to study the effects of reduction ratio, friction factor and die length. Elliptical, trocoidal, rounded square and clover sections are examined for validating the proposed methodology.