Simulation of Torsional–Axial Chatter Vibrations in Indexable Drilling for Noise Generated

Abstract

Nowadays, indexable drills are the most commonly used drills for short hole-making operations because of their high performance and economic usage. Although there is much advancement in the indexable drill designs, they make high-pitched noise during the drilling operation which is unpleasant, cause poor surface finish, and may damage the tool too. Regenerative chatter vibrations are the main cause for this high-pitched noise, and a study conducted showed that the coupling between the axial and angular deflections in these drills causes the chatter. Thus, a numerical simulation model of the chatter occurring in these kinds of drills is done by considering torsional–axial vibrations. The model is used to predict the dominant frequency of the drill in which it is working, deflections of the drills under vibrations, and the variation in the forces because of these vibrations. Finally, the spectrum obtained from the noise generated, during the drilling operation, is compared with the spectrum obtained from the simulation, which shows that the numerical simulation is giving the agreeable results.