The Benefit of In-Bit Sensing for Efficient Drilling of Deep Reach Lateral Wells in HFTO Prone Interbedded Abrasive Lithologies in North America Land

Abstract

Abstract Reaching the pay zone of deep lateral wells requires several bits due to vibration-prone interbedded abrasive lithologies in North America Land. Excessive wear of cutters combined with extreme torque fluctuations results in reduced ROP and premature failures of BHA tools. Early POOH leads to 24 h to 48 h of non-productive time due to BHA tripping. This puts enormous economic pressure on these challenging pay zones. This paper presents a detailed analysis of downhole and in-bit sensing data to increase the operational stability window enabling enhanced bit durability and smoother drilling conditions for economic drilling of long lateral wells. The proposed bit's operation optimization framework is based on a detailed analysis of in-bit high-frequency gyroscope and accelerometer data correlated to vibration and Gamma-ray measurements of MWD and LWD tools. The data analysis reveals High-Frequency Torsional Oscillation (HFTO) prone formations and HFTO frequencies, amplitudes and durations while drilling in lithologies with different rock strengths. The results are compared to lab tests drilling on a full-scale drilling rig using representative rock cores under high confining pressure. The lab measurements are used to model the performance of drill bits accurately and develop best practices for operations. An operational stability map and a drilling guideline have been built and communicated with the region to enable longer reach wells and stable drilling. The data analysis shows a correlation between the lithological shaleness factor and the BHA sensitivity to excite HFTO among other vibrations. The higher the shale content of the gamma ray track the lower the probability of triggering HFTO. These findings are reflected in the lab while drilling interbedded cores at high confining pressure. The data are used to calibrate bit models for design optimization. The application of drilling guidelines on operating 9 bits resulted in a total savings of $500K per well and reduced the non-productive tripping time by 4 days. Guided drilling practices increased the drilled footage per bit by 50%, and reached the same dull state as previous operations. Control of HFTO and vibrations reduced early failures of BHA tools enabling longer intervals and less unnecessary trips. The lack of wire line logging in extended reach lateral wells limits the understanding of targeted formations. This framework enables deeper formation insights that unlock the optimization of performant drill bits. The adoption of this practice promises longer footage per bit, less downhole vibrational issues, and efficient completion of interbedded abrasive lithologies in the future.