Paper 13: Industrial Application of Limit Solutions for Combined Extrusion

Abstract

Experiments on combined rod-can and tube-can extrusion of steel and aluminium have shown that lower pressures are required than those to extrude a single product at the lower of the two reductions in area. As much as 44 per cent reduction in extrusion pressure has been obtained.

An upper-bound solution for rod-can extrusion has been developed which predicts most of the experimental results to within 10 per cent. A simple empirical relationship has been proposed which gives a fair prediction of both extrusion pressures and flow.

A sequence of operations for forming a particular industrial tube-can component was studied and recommendations for its modification made in the light of experience gained from the combined extrusion experiments. The design of a tool which could be developed to control the flow during combined extrusion is described.

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