Integrated Dynamic Modeling and Design Improvement of BHA Configurations for ROP Enhancement in S-Type Trajectory Well: A 12-1/4” Section Case Study

Abstract The rate of penetration (ROP) is a key metric in drilling performance, directly impacting well construction time and cost. In complex and deviated wellbore trajectories, ROP is often reduced due to lateral forces, torque, drag, and vibration acting on the Bottom Hole Assembly (BHA), leading to dysfunctions like stick-slip and buckling. These mechanical inefficiencies not only affect drilling speed but also compromise the structural integrity of the BHA, potentially increasing non-productive time (NPT). Traditional BHA designs often rely on static analysis and rule of thumb sizing, which may not be adequate in dynamic, high-curvature environments. Therefore, integrating simulation-based analysis becomes essential for anticipating real time mechanical responses. This study presents an iterative strategy BHA design configurations for the 12-1/4” section of the R-3 well using API RP 7G principles integrated with WELLPLAN ™ simulations. The results show a 55.2% reduction in lateral forces and improved ROP in high-curvature zones, demonstrating the effectiveness of dynamic modelling in enhancing drilling performance in challenging directional wells. The findings emphasize the value of a performance-based approach to BHA design, incorporating trajectory-specific load behaviour and stiffness matching to mitigate downhole risks and improve operational efficiency.