KINEMATIC RESPONSE OF PDC AND ROLLER-CONE DRILL BITS

Abstract

This paper investigates the kinematic response of PDC and roller-cone drill bits under varying drilling conditions. Particular attention is paid to the influence of combined rotational motion, cutter geometry, and kinematic parameters on load distribution, contact trajectories, and rock-breaking efficiency. The analysis is based on a synthesis of numerical and experimental studies, including kinematic modeling of PDC bits in compound drilling [1] and three-dimensional finite element simulations of rock cutting by PDC cutters with experimental validation [2]. The results demonstrate that kinematic variations lead to non-uniform load distribution on cutting elements, changes in contact stresses, and cyclic behavior of cutting forces, significantly affecting penetration rate and tool wear. It is shown that optimization of cutter rake angle, depth of cut, and motion parameters can enhance rock-breaking efficiency and extend bit service life. The findings provide a basis for comparative analysis of PDC and roller-cone drill bits and contribute to the development of optimized drilling modes and cutter design strategies.