Improving Rotary Steerable Curve Performance Through Automated Analytics and Advanced Modeling
Authors: Wilson J. K. , Brock R. J. , Robles E. 
Published: February 2025

Abstract
Rotary-steerable systems (RSS) have gained prominence in modern drilling operations, in large part for their ability to keep the drill string rotating while maintaining precise directional control. This technology enhances drilling efficiency, enables longer laterals, and can ease post-drilling operations such as running casing. However, achieving consistent directional performance with RSS technology, particularly in high dogleg severity (DLS) applications, remains a challenge for many providers. This study highlights how this specific challenge has been overcome through the implementation of advanced analytics and engineering workflows.
Early deployments of this RSS technology revealed inconsistent build rate performance when drilling curved wellbore sections, despite simulation and modeling results indicating that this should not be the case. Various sources of this discrepancy were examined including modeling limitations, Bottom-Hole Assembly (BHA) configurations, bit design, formation effects, and operational practices. Based on the various investigations, several adjustments were made not only to the design of the tool and the BHA, but the general approach to modeling the directional behavior of the drilling system and the evaluation of these drilling systems in the field. The resulting changes have subsequently resulted in more consistent dogleg output from the RSS, often exceeding well planning requirements. Further optimization studies were conducted to better understand the downhole mechanics of the "high DLS output" scenario, seeking to minimize undesired wellbore curvature. The findings guided the development of an enhanced procedure for drilling the curved wellbore sections.
The updated procedures have demonstrated improved consistency in the curved wellbore sections, aligning directional output more closely with the well plan while improving the rate of penetration (ROP). Maximum dogleg severity values have been routinely measured over 15°/100ft in multiple basins. This has enabled enhanced precision in landing the well in the desired zone and faster drilling of the curve sections. The standardized operating procedures have been successfully applied across various basins, including the Permian, Scoop/Stack, and the Marcellus, covering a wide range of applications, from simple 2-D curves to complex 3D curves with extensive step-outs. These developments have resulted in a comprehensive RSS service that consistently delivers high-quality directional performance, with the potential to perform in new applications. In addition, an automated algorithm for evaluating the directional performance of the RSS in the curved section of the wellbore has helped to compare performance between BHA configurations and enabled optimization comparisons for different drilling scenarios.
This study presents an innovative approach to achieving reliable curve performance with a high-performance rotary-steerable system. The methodology, grounded in physics-based analysis, has demonstrated its value across multiple basins, and continues to move the status-quo of directional performance upwards.