Papers by sebastien reboul
Improving the Directional Behavior of PDC Bits Affected by Stick-Slip: A Statistical Approach
Day 7 Mon, March 29, 2021, 2021
Torsional vibrations are a very common phenomenon affecting drilling operations by limiting effic... more Torsional vibrations are a very common phenomenon affecting drilling operations by limiting efficiency, increasing the risk of downhole equipment failure and generating additional costs, particularly when their most severe form is encountered, the stick-slip. It is less known that torsional vibrations also strongly affect directional drilling operations reducing directional stability and tool face control. In this paper, the highly variable solicitation induced by torsional vibrations is addressed with a statistical approach. This approach, used successfully in Kuwait applications, resulted in an operational savings of 30% of the cost per foot over a panel of more than 15 runs analyzed.Steerability and directional stability is critical on directional wells, especially when using push-the-bit systems with PDC bit due to side force distributed unevenly over one bit revolution. Most of today bit design comparisons are made with an average steerability factor computed over one full revo...
Day 1 Mon, November 15, 2021, 2021
Drilling into harsh environment with heterogeneous formations including chert or conglomerate is ... more Drilling into harsh environment with heterogeneous formations including chert or conglomerate is usually a boundary that can't be crossed with standard PDC bit technology. This paper will show how an innovative PDC cutter shape combined with a novel 3D approach of cutting structure design have withstood this challenge and successfully replaced 16-in. traditional roller cone application in United Arab Emirates by the latest PDC technology delivering an average 35% improvement on Rate Of Penetration (ROP) while continuously drilling to Total Depth (TD) on each section. When drilling chert or conglomerate type of formation with a PDC drill bit, uneven load per cutters is detrimental to their integrity and results in short runs or brutal stop in the drilling operation triggering a trip for drill bit change. The new technology shown in this paper includes a unique hybrid combination of cutter shapes with a design arrangement of the cutting structure to allow for the pre-fracturing of...
Setting a New Standard: PDC Bits Equipped with Compact Vibration Recorders Monitor Entire Run and Reveal Stick-Slip Mitigation System Dysfunction and Downhole Motor Under Performance
Day 2 Tue, March 09, 2021, 2021
Downhole vibration measurements are used real-time and post-run to monitor drilling dynamics. Rea... more Downhole vibration measurements are used real-time and post-run to monitor drilling dynamics. Real-time monitoring tools are applied to facilitate immediate corrective actions but their deployment adds operational constraints and costs. This paper describes a new high-capability vibration recorder embedded in the drill bit as a standard component. The analysis of two case studies in the Middle East shows how memory devices available at a reduced cost and on every run are a valuable option for many appraisal or development wells.Developing a fleet of reliable downhole recording tools typically takes years and involves teams of experts in various fields. The paper describes the strategy followed by a drill bit manufacturer to develop and deploy a compact, high capability and cost-effective vibration recorder to provide continuous readings of accelerations, rotation speed (RPM) and temperature at 100Hz and over 250 hours. Sensors and batteries have been packaged to fit into the drill b...
Day 3 Wed, November 13, 2019, 2019
Simulating the mechanical response of PDC drill bits contains a lot of uncertainties. Rock and fl... more Simulating the mechanical response of PDC drill bits contains a lot of uncertainties. Rock and fluid properties are generally poorly known, complex interactions occur downhole and physical models can hardly capture the full complexity of downhole phenomena. This paper presents a statistical approach that improves the reliability of the PDC bit design optimization process by ensuring that the expected directional behavior of the drill bit is robust over a well-defined range of drilling parameters.It is first examined how uncertainty propagates through an accurate bit/rock interaction model which simulates numerically the interaction between a given PDC drill bit geometry and a given rock formation, both represented as 3D meshed surfaces. Series of simulations have been launched with simulation parameters defined as probability density functions. The focus has been set on directional drilling simulations where the drill bit is subjected to significant variations in contact loads on ga...
A New Pdc Bit Selection Method Based on 3d Realistic Cutter Damage Simulation Aimed at Maximizing Product Life–Cycle
Increasing the life of PDC bits without compromising on bit performance is crucial in drilling op... more Increasing the life of PDC bits without compromising on bit performance is crucial in drilling operations. It allows the operator to reduce non-productive time and the bit manufacturer to increase the reliability and the repairability of its products. This paper introduces a new PDC bit selection method designed to maximize the durability of the selected bit based on simulations of 3D realistic cutter damage. During PDC bit drilling operations, any damage caused to one cutter tends to overload others and compromise the balancing and the durability of the whole cutting structure. The impact of various kinds of bit failure and cutter damage on the performance of different cutting structures is estimated. The analysis is performed with the help of a 3D bit-rock interaction model which simulates the drilling process considering both the drill bit and the hole being drilled as 3D meshed surfaces. The simulator is based on a generic computational geometry algorithm which estimates the exa...
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Papers by sebastien reboul