CONCAVE PDC CUTTER

Abstract

The relevance. Vibrations of a drill string of any origin, arising while drilling a well, lead to a decrease in the quality of the work performed. The known methods of combating this phenomenon are technically and technologically complicated. When drilling with a PDC-type rock cutting tool, one of the reasons for the occurrence of lateral vibrations of the drilling tool is the low level of friction forces of the working edge of the cutters against the rock. Modern possibilities for the synthesis of diamond material make it possible to manufacture PDCs of various shapes and sizes. Developments in the field of creating a PDC cutter with a concave working surface contribute to the development of methods for preventing lateral oscillations of the cutter, and as a result, reducing the vibration level of the entire drill string. The purpose of the research is to develop the design of the PDC-type rock cutting tool, which helps to damp the vibration of the drill string. Methods: method of computer simulation, method of scientific knowledge, analytical research, analysis. Results. The forces arising on the concave surface of the PDC cutter are directed towards each other, counteracting and preventing lateral displacement of the drilling tool. The optimal angle of concavity of the working surface of the cutter should be in the range from 104 to 155 degrees, it is this range of angle values that contributes to the creation of optimal conditions for the performance of the bit while maintaining the anti-vibration effect. The design of the PDC cutter with a concave cutting surface in the form of a cone or sphere allows not only reducing tool vibrations, but also contributes to cleaning the bottom and creating a zone of pre-fracture of the rock in front of the cutter due to the energy of the jet of drilling fluid, which increases the efficiency of rock destruction.

Keywords

• drilling
• vibration control
• pdc cutter
• computer simulation
• hydraulic processes
• rock formation