A Holistic Approach to Quantifying and Controlling the Accuracy, Performance and Availability of Machine Tools

With today’s ever increasing demand for improved accuracy and faster material removal rates, CNC machine tool manufacturers and users are under pressure to supply and maintain machinery with a high degree of accuracy and performance. Although some machine tool users have their machines “checked”, there is no formal method of establishing the capability of a machine tool as an overall measure of its performance, accuracy and availability. This paper identifies the key performance indicators for modern CNC machines and highlights the technical difficulties in understanding machine tool capability. To solve the problem, a novel method of measuring, analysing and controlling the overall capability is presented. The philosophy and process of machine performance evaluation, optimisation and monitoring (MPEOM) is explained. The paper also illustrates how conventional “Lean” techniques can be utilised to simplify the complex area of machine tool metrology allowing for the integration of the process into modern manufacturing systems.