The measurement and stochastic modelling of torque and thrust in twist drilling

Publisher Website
Google Scholar
Abstract
This work deals with the measurement and analysis of torque and thrust in drilling mild steel using twist drills. Force and torque measurements were carried out using a specially designed two-component piezoelectric dynamometer. The dynamometer was both statically and dynamically calibrated, and techniques for increasing the measuring accuracy and reducing cross-interference were employed. Experiments have been carried out to measure the drilling torque and thrust in mild steel under different cutting conditions. Recorded data from the dynamometer were processed and an analysis was carried out to determine major statistical properties of the drilling torque and thrust. For each recorded cutting force signal, analyses were performed to determine the mean value, standard deviation, probability density, power spectral density and the autocorrelation function of the fluctuations in torque and thrust. Results of the above analysis show that the dynamic fluctuations of torque and thrust in drilling are stationary and random with Gaussian density function. An attempt has also been made to model the cutting torque and thrust in drilling mathematically, It is expected that this formulation will be useful in analysing the dynamic behaviour and stability of drilling machines.

This publication has 7 references indexed in Scilit: