Comparative Study on Rock-Breaking Characteristics of PDC Cutters Assisted by Pulsed Laser versus Continuous Laser

Abstract To improve the efficiency of deep oil and gas resource extraction, a laser-assisted PDC bit rock-breaking drilling technology is proposed. The evolution of cutter loads and the rock-breaking mechanism under laser irradiation were investigated through experiments and numerical simulations. Experimental results show that under pulsed laser assistance, the average cutting force of the PDC cutter was reduced by 82.89% compared to drilling without laser assistance. Numerical simulation results indicate that pulsed laser irradiation induces localized vaporization and thermal stress damage in the rock, significantly weakening its strength. Compared with continuous laser assistance, pulsed laser conditions reduce the stress in the central cutting zone by 20%, the cutting force by 20.4%, the variance of the cutting force by 48.8%, and the specific energy for steady-state cutting by 19.8%. The research findings support the development and engineering application of laser–PDC bit integrated rock-breaking drilling technology.