An analytical evaluation of the cutting forces in self-piloting drilling using the model of shear zone with parallel boundaries .1. Theory

The performance of a self-piloting tool is affected by its design and geometry parameters. These parameters constitute the tool-force system which directly defines quality of the machined holes, tool life and required power. This paper presents an analytical approach to describe the cutting forces in self-piloting drilling. The approach is useful at the level of tool and process design. The subject has been covered in two parts. Part one deals with the analysis of the cutting mechanics employing the shear-zone model with parallel boundaries. The analysis of the continuity condition results in better understanding of the traditional cutting model's characteristics, such as the chip compression ratio and velocity diagram. Based on this analysis and using the thermomechanical model of the work-material resistance to cutting, a cutting-force model is proposed and has been verified experimentally. Copyright (C) 1996 Elsevier Science Ltd