Optimizing The Planning, Design And Drilling Of Extended Reach And Complex Wells

Abstract

Extended Reach Drilling (ERD) is an integrated methodology for drilling high-angle wellbores with long horizontal displacements. Several problems are associated with extended reach wells. Thus for high levels of performance improvement to be achieved, it is essential to analyze the interrelationship among the elements involved in the entire drilling process. This is because a system that considers the individual elements of the drilling system in isolation is inadequate to deliver desired performance improvement.In this study, an algorithm that sets forth a design for a drilling program that is suitable to drill an extended reach well was developed using Visual Basic. Although the algorithm touches on several factors affecting extended reach drilling, the major focus is on the six elements, which are considered the critical factors. These are: Well Trajectory Design, Bottom Hole Assembly (BHA) Design, Bit Hydraulics, Drill String Design, Torque and Drag, Hole Cleaning and ECD Management. The proposed algorithm evaluates the interrelationship among these critical factors and provides direction on the processes and tasks required at all stages in the design and drilling of an ERD well to achieve maximum drilling performance. The development of the model is based upon information gathered from several sources, many new ideas from technical publications, along with information and feedback from field-based personnel. The output generated from the model compare well with results from actual field data.

An Analytical Model for Axial Force Transfer and the Maximum Compression Point of Work Strings in Extend Reach Drilling

“…Samuel [19] presented a new well-path design that can extend the reach of ERW through reducing torque and drag using curvature and torsion discontinuities. Agbaji [20] presented an algorithm that would set forth design for drilling programs suitable to ERD. Vestavik et al [21] presented a potential application of Reelwell Drilling Method (RDM) to widen the envelope of ERD through reductions of torque and drag and Equivalent Circulating Density (ECD) gradient, and optimization of hydraulic weight on bit.…”