Hybrid Drilling Dynamics Downhole Measurements

Abstract In the continuous pursuit of enhancing the efficiency and safety of drilling operations, the optimized placement of downhole sensors has emerged as a pivotal area of innovation. This paper presents an optimized configuration for sensor placement, meticulously designed to advance the understanding and control of drilling dynamics. By integrating high-resolution sensors capable of measuring three-axis acceleration, revolutions per minute, weight on bit (WOB), and torque, an optimized approach to monitor and analyze a drilling system's performance can be established. The methodology emphasizes steering efficiency, system integrity, and scenario-specific relevance, catering to a wide range of operational challenges. Several key scenarios are addressed, including high-frequency torsional oscillations (HFTO) detection and mitigation, backward whirl detection indicative of motor failure, motor micro stall conditions, reamer deployment strategies, comprehensive performance optimization, and stick/slip detection for preventing twist-offs. Based on this, the sensors are positioned at the most sensitive spots within the bottom hole assembly (BHA), ensuring a precise characterization of the excitation and distribution of critical stresses. Combined analysis of field data and 4D (3D in time domain) drilling dynamic simulations (Chen et al, [2015]), has affirmed the efficacy of the recommended sensor placement strategy in improving drilling efficiency and reducing operational hazards. The simulations particularly highlighted the capability to infer measurements from sensor data across different BHA components. It was also determined that WOB and torque on bit measurements from elsewhere in the BHA could be confidently inferred at the drill bit through extrapolation. Field data analysis further revealed that capturing burst acceleration data at the drill bit, integrated with a digital solution, effectively identifies HFTOs, facilitating their mitigation. Additionally, positioning a torque sensor just above the steering unit, where significant bending occurs, can prove instrumental in predicting HFTO-related fatigue life with considerable precision. Leveraging field data alongside advanced 3D dynamic simulations has led to the identification of an optimized sensor positioning. This versatility across numerous drilling scenarios, ensures the integrity of the drill bit while seamlessly integrating with the steering mechanism.