Abstract
In order to improve the drilling efficiency of bit drilling in poor-drillability formation, the authors of this article put forward a cutting–percussion hybrid bit, the fixed-cutting units and impact-crushing units of which are mutually independent and are able to work in parallel. Through finite element analysis, it is concluded that the impact teeth will degenerate the material and mechanical properties of the rock, and that the polycrystalline diamond compact cutters will remove the pre-damaged rock with relatively low energy consumption, thus improving the rock-breaking efficiency of the bit. Moreover, on the basis of the geometrical and kinematical characteristics of the hybrid bit, geometrical relationships between the teeth and the bit body, as well as the kinematics and kinetics of the teeth, are studied in compound coordinate systems. Furthermore, by programming in MATLAB, the rock-breaking process of the hybrid bit is simulated and the simulation results consist of the bottom-hole profile, cutting area, cutting volume, and cutting force of the cutters, providing the theoretical basis for the research and development of the hybrid bit.
Highlights
For deep and ultra-deep wells, the drilling cost of poordrillability formation accounts for a large proportion in the total drilling cost
If the bottom-hole rock is of high hardness or high strength, it is difficult for the polycrystalline diamond compact (PDC) cutter to penetrate the rock and complete a valid cutting process, especially when the cutter is worn after a period of drilling, it will be even more difficult for the cutter to penetrate, rate of penetration (ROP) of the bit will be significantly lowered.[1,2,3,4]
Aiming at solving the problems existing in PDC bits and hammer bits, the authors of this article put forward a cutting–percussion hybrid bit to improve the ROP of bit drilling in poor-drillability formation
Summary
For deep and ultra-deep wells, the drilling cost of poordrillability formation accounts for a large proportion in the total drilling cost. Velocity, acceleration, and kinetic equations of the hybrid bit cutter are established based on the composite kinematics model, based on which the dynamic rock-breaking process of the hybrid bit is researched by utilizing the numerical simulation method.[13,14,15,16,17,18,19,20]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
