Influence of the cutter geometry in rock cutting

Since the early nineties a lot of researches have been realized in rock cutting with PDC cutters. In 1992 Detournay and Defourny developed a phenomenological model (DD model) based on the suggestion proposed by Fairhurst and Lacabanne (1957): ''The cutter / rock interaction is characterized by two processes: rock cutting and frictional contact''. Based on the DD model, a testing device has been developed at the University of Minnesota, Minneapolis: the Rock Strength Device (RSD). The RSD is designed to scratch rock samples with a constant depth of cut using a single cutter. It has been developed not only to measure strength parameters of rock specimens, but also to understand the mechanisms involved in rock cutting. Several research aspects have been studied on the RSD to valid the DD model. Lasserre (1994), Adachi (1996), Nicodème (1997), Richard (1998), Lhomme (1999) have studied different particular topics such as the correlation between specific energy and rock properties, failure mode in rock cutting, friction phenomena. Richard (1999) suggested the existence of a 3D effect influencing the specific energy. No real research approach has been conducted to understand the so-called 3D effect. This was the objective of this research.