A Path to Drilling Efficiency: The Impact of Eccentric Reamer and Bit Design on Operations in the Llanos Basin, Colombia

Abstract In Colombia's Llanos Basin, the implementation of the eccentric reamer and bit design has led to significant improvements in performance and time optimization, achieving a remarkable 76% increase in rate of penetration (ROP) and a 33% reduction in bottomhole assembly (BHA) trip time to surface. It also helped reduce wellbore tortuosity and enhanced hole quality prior to casing operations. Additionally, casing running times were reduced by 31%, leading to faster and more reliable delivery. These results are particularly significant in the Llanos Basin, which presents multiple well design constraints, trends of formations, operational limitations, placement of the electrical submersible pump (ESP), casing depth, tripping time issues, and torque and drag considerations. The collaborative engagement between GeoPark's drilling team and strategic partners enabled the identification of the most effective BHA configurations, resulting in measurable performance gains. Simulations and downhole measurements validated the effectiveness of the technology, showcasing its practical applicability and benefits in the field. The authors evaluate the use, value, and benefits of implementing a novel eccentric reamer and bit combination in drilling operations in the Llanos Basin, Colombia. The focus is on improving borehole quality, ROP, and tripping efficiency, all of which contribute to the overall performance of the casing run and accelerated well delivery, especially in wells with high inclination and operational constraints.