Development of a geometrical torque prediction method (GTPM) to automatically determine the relative torque for different tapping tools and diameters

Abstract

This research paper presents the development of a geometrical torque prediction method (GTPM), which could be used to determine relative torque values for tapping processes with various tapping tools and diameters. Experimental tests and three-dimensional finite element method (FEM) simulations were carried out using four different tap tools that are frequently used in practice. A segmented workpiece model, which could significantly reduce the computing time of the FEM tapping simulations, was validated by comparing the results to the experimentally obtained data. The determined relative torque values show a parabolic progression with rising tool diameter, which is the reason why the GTPM could be developed on this basis, to further reduce the high computing time and optimize the tool design process without the production of costly prototypes. To verify the developed GTPM, the according predicted relative torque values were compared to the previously carried out simulations and experiments, showing a good agreement. A FEM software module was created to implement the developed methods in an interactive and automated way, providing an efficient method to improve the tapping tool development process.