Optimum energy utilisation is a major concern during machine tool design, as not only is energy consumption an environmental impact/sustainability indicator; it also affects the production economics. Most electrodischarge (EDM) machines have a high degree of automation allowing better coordination of energy consuming subunits for a given machining parameter. The purpose of this study is to analyse the variation of energy consumption with unexpected wire breakages during machining. An industrial CNC wire EDM operation of aluminium and steel plate cutting is studied. A time study and an energy study are performed involving all sub units of machining operation. Results are presented and justifications are made for the fluctuations in total energy consumption during wire breakages. Further, an environmental impact study comparing wire EDM with and without unexpected wire breakages is presented drawing insights for machine tool design and operating practices.
