A generative process planning system for cold extrusion

In this paper, a CAPP system GIFTEP (Generative, Interactive, Feature-based Technology for Extruded Products) based on a generative approach is proposed for forward cold extrusion of complex-shape solid components to be extruded through single-hole dies. This is an attempt, using the previous efforts of Kumar et al. 1999 and 2002), made by the authors to bridge the gap between CAD and CAM practices related to cold extrusion. A feature recognition methodology, an upper bound model, an optimum die profile, a defect prediction criteria, criteria to choose a die arrangement and a simple adiabatic model to account for the temperature of extrudate proposed in the previous work of Kumar are taken as the foundation modules for the purpose. Based on the component layout, a recognition module provides necessary data to carry out the die design process. The input parameter selection module first selects the input parameters provided by the user (material, reduction, billet condition, production type, etc.) or the default values from a database (die material, profile, die arrangement, accessories, etc.). The process parameter determination module carries out the optimization and calculates the optimal process parameters for two different criteria. Finally, an optimal process plan corresponding to both criteria are generated. The methodology is implemented in C through examples.