Modelling the Effects of Workpiece Flexibility on Cutting Performance in Turning Operations

Abstract

Machining is fundamentally a process of material removal. Therefore, machining productivity can be conceptualized as the rapid elimination of a substantial machining allowance, implying a reduction in machining time. This research has yielded a computational model predicated on beam deflection, factoring in the influence of workpiece flexibility on cutting forces, and its repercussions on the material removal rate and precision. The model facilitates the calculation of actual turning productivity. The methodology incorporated modeling the static response of the flexible workpiece to the thrust component of cutting forces. The impacts of flexibility on the beam model responses concerning the material removal rate, and deviations from the desired shape and size were scrutinized. A computational approach, experimentally corroborated, was applied. This approach necessitates cutting force coefficients, which were ascertained through cutting tests and pseudo-inverse regression analysis. The experimental setup for the cutting test incorporated a locally constructed dynamometer for measuring cutting forces, displays on both an LCD and a computer monitor for recording cutting force readings, a cutting tool, and a workpiece. Judging by the coefficients of determination, R 2 values of 0.97, 0.89, and 0.93 of the regression calibrating the force coefficients for the tangential, feed, and radial directions-which are used to gauge the accuracy of the determined force coefficient and are typically one or close to one-the derived force coefficients demonstrate high reliability. The developed model is projected to yield significant industrial-economic benefits by curtailing the costs of finishing operations on the CNC lathe machine, owing to the provision of a chronological path to follow while working on a flexible workpiece.

Development of Theoretical and Numerical Framework for Selecting the Cutting Process Parameters for Turned Slender Parts

“…Machining efficiency is measured by considering machining time, material removal rate, and the economics of machining. To put it simply, the overall machining time or the total time for machining (Tm) is the sum of all three individual time components that are directly associated with the machining process, as indicated in reference [41].…”