Drilling Automation: Revisiting the Digital Drilling Program

Abstract In parallel with the increasing adoption of drilling automation at the rig site, there is a notable emphasis on the digitalization of the drilling program. These activities should not be viewed in isolation, as reinventing the drilling program may lead to significant breakthroughs in how automated processes are seamlessly integrated into drilling operations. Drilling operations are largely predictable, with parameters such as the number of sections and stands typically set in advance and rarely updated. However, significant uncertainty often exists regarding formation depths, and geomechanical limits may differ from those prognosed. Additionally, the state of the drilling system is never known with certainty and can be significantly impacted by factors such as cuttings transport or drill-string vibrations. Furthermore, unexpected drilling events occur frequently, forcing the drilling crew to adapt to unforeseen circumstances that were not defined in the original plan. Efficiently managing uncertainty requires more of a strategy than a plan, enabling adaptation to various situations while fulfilling the objectives of the drilling operation. A set of strategies can then be directly utilized by drilling automation functions during well construction. These strategies form the foundation of a new version of the digital drilling program. The implementation of the digital drilling program presented in this paper is based on a top-down analysis that refines well design choices by controlling the level of detail. These choices are guided by constraints and uncertainties established by a multidisciplinary well engineering team. To avoid a combinatorial explosion in the number of considered drilling scenarios, the algorithm balances exploration and exploitation constraints at each stage of the optimization process. A similarity metric is defined to group together connectively equivalent scenarios, which are passed to the next step of the iterative process, resulting in only a few hundred possible solutions to work with, rather than an overwhelming number. At any stage, each possible choice is evaluated from a multi-objective perspective, such as through directional, hydraulic, or mechanical simulations. However, the level of detail for this evaluation varies with the depth of investigation. This approach helps uncover, as early as possible, alternatives that are not viable, allowing them to be discarded. Using this framework, the engineering team is left with a manageable set of design choices that respect its own rules and constraints, widely and efficiently sample the parameter space, and can be filtered and sorted to retain the most robust and effective well construction solutions. Digitalization is not only about the seamless transfer of information. By envisioning a comprehensive digital workflow from well design, engineering, and planning to construction, it is possible to optimize drilling operations to an extent previously unattainable.