PDC bit has poor adaptability in soft and hard staggered, gravel-bearing and other heterogeneous layers and hard formations. The problem of easy pre-damage of the cutting teeth of the bit has not been solved yet. A shaft-tilted PDC bit tool is proposed. The most obvious feature of the tool is that the bit body is designed as an "axial-tilted" structure, which can realize the alternating trajectory movement of the cutting teeth under the cooperation of supporting tools. Researching and analyzing the corresponding theory of the shaft inclination PDC bit, conducting laboratory experiments to analyze the influence of transmission ratio and shaft inclination angle on drilling efficiency, revealing the rock breaking mechanism of the tool. This technology can effectively enhance the intrusion capability of PDC bits in complex and difficult-to-drill and deep formations, and improve rock breaking efficiency. This can provide beneficial support for the drilling industry, especially for deep and ultra-deep well drilling, to speed up, increase efficiency, and reduce costs. Contribute to the progress of our country's drill bit technology.

Haitao Ren, Haiping Tian. Rock Breaking Mechanism and Experimental Research on Axial Tilt PDC Bit Tool. Academic Journal of Engineering and Technology Science (2021) Vol. 4 Issue 1: 82-91. https://doi.org/10.25236/AJETS.2021.040109.

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