Combined Optimisation of Machining Parameters, Tool Wear, Dimensional Errors and Quality Deviations in Multi-Pass Turning Operations

Measurements of on-line tool wear and part dimensional accuracy in machining operations are not readily available in machining shop floor because they involve higher investment such that the decisions of tool wear and part quality for intermediate cutting passes cannot be justified. This paper demonstrates how the optimisation of machining parameters can be made together with tool wear and part quality for turning operations. Two optimisation models were developed for maximum material removal rate and minimum production cost. A theoretical framework was initially presented before the two models were formulated. Input data for the models were adopted from previous studies while the optimisation analyses were conducted using LINGO 21.0 software. The results show that efficient machining parameter, tool wear, dimensional errors, and quality of surface finish can be achieved in a combined optimisation problem. Additionally, the results supported the importance of using identical machining parameters for rough cutting passes rather than non-identical machining parameters. This is due to the fact that the material removal rate increases by 33.3% with identical machining parameters in rough passes as compared to non-identical parameters while the production costs decrease in the range from 30.5%-33.7%. It indicates that identical machining parameters for rough passes are cost effective and simplify machining process planning.