Engineering Ceramics Plant, Aprelevka, Russia:

Beshenkov P. S., Technologist

National University of Science and Technology—MISIS, Moscow, Russia:
Polushin N. I., Associate Professor, Candidate of Engineering Sciences, Head of Superhard Materials Research Laboratory
Gkhorbani S., Lecturer, Candidate of Engineering Sciences, siamak.ghorbani@misis.ru
Sorokin E. N., Senior Researcher

Bits equipped with polycrystalline diamond compact (PDC) cutters are used in different purpose drilling in soft, medium-hard and, sometimes, hard rocks. The drill bit load, speed and torque, as well as density and cutting angles of cutters influence the PDC drilling efficiency. Improvement of drilling performance is one of the top priority economic goals. Production drilling is faced with a lot of technical problems to be solved to ensure high quality and efficiency of drilling. One of the predominant objectives of drilling is to select the best drill bit and to determine optimal drilling parameters as they directly govern the hole drilling cycle, the drill bit life, as well as the time and cost of drilling. Stresses in the body and cutting elements affect the behavior and productivity of PDC drill bits, as well as the running characteristics and failure-tolerance of cutters. High stresses can induce separation of the diamond compact top from the tungsten carbide substrate and initiate microcracks in the diamond layer. The microcracks grow and promote critical degradation of cutting tools in the course of drilling. The specified problems are commonly solved using software programs such as Solidworks Simulation, that make it possible to perform strength analysis, to obtain stress distribution patterns and to account for the influence exerted by angles of attack of PDC cutters on their stress state. This study is focused on stress distribution in cutting elements of PDC drill bits. The forces applied to the cutting elements of PDC drill bits are determined in the normal conditions and under critical impact loading. The effect exerted by the angles of attack of PDC cutters on the stress distribution and magnitude in drill bits is revealed.
This study has been carried out in the framework of the Federal Targeted Program on R&D in Priority Areas of Advancement in the Science and Technology of Russia for 2014–2020 in accordance with the Project on Development of the Technology for Production of Nanostructure Materials for Load-Bearing Substrates with High Impact Strength under the Grant Agreement No. 14.579.21.0093 dated July 27, 2015 (Unique Agreement Identifier FMEFI57915X0093) within the Integrated Project on the Technology of High-Efficient Horizontal and Inclined Drilling Bits for Oil and Gas Industry.

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