Abstract
In the injection forming/upsetting of tabular parts the ratio between inner and outer diameters of the tube, the ratio between wall thickness and gap height, together with the design of the die chamber are important dimensional parameters that determine the final geometry of a component. Recent published work in this field opened a breakthrough in the understanding of the limits for obtaining sound components without folds. However, some difficulties were still encountered, namely in what concerns avoiding the presence of undesirable models of deformation.
The paper presents comprehensive modelling of previous experimental work in this field, which leads to a re-examination of the process mechanics. This effort resulted in the development of a combined injection forming/upsetting technique. Numerical simulations performed using this technique indicate that a large extension of the formability limit for tubular components is possible.