The scientific and technical journal, “Bulletin of the Association of Drilling Contractors”, is listed by the Higher Attestation Commission of the RF Ministry of Education and Science as one of the leading refereed journals and publications that feature main scientific results of doctoral and candidate’s dissertations.
Key words: drill bit, fatigue failure, rock, cutting structure, stress cycle, weight on bit.
The article focuses on the history of the study of fatigue breakdown of rocks. The number of cycles in fatigue breakdown of rocks is many hundred thousand times less than that of metals. Fatigue breakdown always occurs while drilling because weight on bit is not sufficient to destroy rocks by a single movement of the bit.