Electrical Discharge Machining (EDM) is one of progressively developing machining technology. Its advantage over other progressive machining technologies is the high achieved accuracy of the machined surface. Moreover, in this case, it is machining without force, which means that the mechanical properties of the material to be machined do not impose almost any limits. However, during EDM, the material is not only removed from the workpiece, but also from the tool electrode, causing wear. However, a number of factors have an impact on the Tool Wear Rate (TWR) during the electrical discharge process. It is mainly its chemical and physical properties, the type of material being machined, but also its geometric shape. Therefore, based on the experimental measurements performed, the aim of the paper was to identify the influence of the geometric shape of the graphite tool electrode on the TWR and MRR size during EDM of tool steel EN 90MnCrV8. On the basis of the obtained results, set recommendations for the correct choice of the geometric shape of graphite tool electrodes used in EDM tool steels.

There are increased demands for safe, reliable and economically efficient operation of modern technical devices nowadays. These technical devices need an appropriate monitoring system in order to fulfil all the requirements. This consequently monitors their activity while providing appropriate information on operating parameters. As a result of them, the control system of a technical device can perform adequate interventions to remove unstable or rather critical condition. Melting furnaces are among devices where the current state of their operation is inevitable to monitor. The monitoring of melt temperature is an inevitable requirement in these devices because of its optimization for casting process, i.e. in order not to degrade its quality due to low or high temperature. Therefore, the aim of the paper is to describe a proposal for a solution of the operating parameters of the gas melting furnace KOV 010/1998, which is in practice used for melting of non-ferrous metals with low melting point. By implementing the proposed solution, its operation should be simplified and more importantly, its operation should be more efficient.