Effect of the interaction between tool and workpiece modes on turning with round inserts

Abstract

In this paper we investigate the effect of the tool-workpiece mode interaction on the stability of a flexible-tool, flexible-workpiece turning process. The workpiece dynamics are modeled by classical beam theory while for the tool we consider a description in terms of eigenmodes with an arbitrary orientation. The focus here is on elucidating the coupling effects due to the flexibility of both structures. Specifically, we show how the tool location along the workpiece and the dynamics of both the workpiece and the tool affect stability. Another contribution of this paper is the utilization of a novel analytical force model for cutting with round inserts. Using this force model, we further show that when round inserts are present, commonly used frequency domain methods can no longer be utilized to capture the system stability. Consequently, we use the spectral element approach, a highly-efficient time-domain approach, for studying the system stability.