The discovery of large oil reservoirs under salt layers is motivating the study of drilling optimization of wells in many basins, notably in Brazil and West Africa. The aim of this paper is to present the laboratory experiments carried out to cut evaporite samples in the so-called single cutter configuration. These tests are meant to generate results to improve the understanding of the mechanics of drill bit - rock interaction. The paper also describes the use of a numerical tool based upon the discrete element method to model the experiments. The laboratory experiments consist in obtaining the forces acting upon a cutter during its penetration and cutting of a groove in a sample of evaporite. These forces are transformed into Mechanical Specific Energy, MSE. The tests were carried out under different depths of cut and back-rake angles. The results indicate that MSE decreases with the increase of depth of cut until a certain limit when it stabilizes. The experiments also indicate that changing cutter inclination changes the cutting forces and mechanisms, and the paper explores these findings. Triaxial confining tests were carried out in cylindrical samples of the same evaporite used in the cutting experiments. The results of these tests were used to create a virtual rock to be treated by the discrete element method. This is an important step in the workflow and is also described in the paper. Finally, the laboratory experimental results are compared with the results produced by numerical simulation. Both 2D and 3D modeling of the single cutter experiments were carried out under atmospheric conditions and satisfactory results were obtained, revealing the importance of the developed methodology in understanding rock cutting mechanisms.
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