Automated Preform Design for the Development of Multi-stage Hot Forging Technology

Producing complex forging parts requires multiple operations depending on the initial billet shape, the desired final forging shape, and the material’s deformability. The intermediate preforming impressions are used to achieve a complete finish die fill with minimal flash and reduced forming load while avoiding flow defects such as laps and flow-through. Practically effective preform design should also minimise the die wear by reducing metal sliding over the tool surface during impressions. In this paper we present a practical implementation of the approach to developing a preform shape that involves a potential flow approximation and utilising equipotential surfaces as a preliminary guess. This study continues the author’s previous work [1], which has been expanded to a broader range of product shapes. To make this approach applicable in the industry, a specialised CAD program was developed and tested in real production conditions that have proven its efficiency.