ISSN 1330-3651 (Print), ISSN 1848-6339 (Online)

Preliminary notes Nowadays, the consideration of environmental protection viewpoints is a social obligation in all fields of life. These expectations are even more increased during the manufacturing of machine industrial products, which is why the demand for the reduction of environmental load is becoming predominant in production. This is why the application of used coolants and lubricants (CL) has gained the centre of interest in metal processing procedures. In the development of machining procedures CL contributes not only to the increase of the effectiveness of material removal but it helps to achieve the appropriate accuracy and quality. At the same time coolants and lubricants, depending on their composition, pollute the environment to different extents. That is why it is an emphasized task of technologists in the planning and execution of material removal to reduce the amount of these auxiliary materials, or do without them if possible. In this paper we focus on the determination of the ratios of the consumed CL in alternative procedures of hard machining. By comparative experiments we examine to what extent the consumption of CL can be reduced in the different procedures without any deterioration in accuracy or surface quality of the machined surface/part.