A computer aided tool selection system for 3D die/mould-cavity NC machining using both a heuristic and analytical approach

Abstract

The selection of cutting tools in die/mould-cavity NC machining affects not only the machining time and costs, but also the process quality. A systematic methodology for cutting tool selection, including tool type and size, for each operation, i.e. roughing, semi-roughing and finishing, is proposed in this article. First, a heuristic-based tool type selection method is discussed. Second, a tool combination optimization approach for roughing is presented and an optimization mathematical model is built. The related algorithms for realizing this approach, including acquiring loop from intersection line segments, identification of inner and outer loops, computation of key distance and merging of hunting layers, are presented in detail. Third, the methods for semi-roughing and finishing tool selection are also outlined. In order to validate the proposed methodology, a system called CATS has been developed in the UG/Open API environments and two examples of cavity with islands are included to demonstrate its feasibility. The work in this research facilitates both the elimination of the experience factors of human tool selection, and the seamless integration of CAD/CAM systems.

Keywords:

• Computer aided tool selection
• Die/mould-cavity
• NC machining
• CIM
• Optimization
• Mathematical model

Acknowledgements

The authors wish to acknowledge the support of the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20020248017) and National Die/Mold Engineering Research Center, People's Republic of China. Special thanks go to our industrial collaborator, Shanghai Shenmo Die/Mold Manufacturing Co. Ltd., for its support for this research work. The authors also wish to thank the two anonymous referees for their positive comments and constructive suggestions that helped to improve this article.