Extended reach [ER] drilling refers to the practice of directionally drilling to a given geological target located at a significant horizontal distance [horizontal departure] from the drilling rig. The ability to perform complex ER operations has become increasingly important in recent years, as the average length of the wellbore horizontal section continue to be extended. Drilling these complex wells, whether it is to reach reserves far from existing facilities or to expose reservoir sections for production and reservoir management advantages, requires accurate planning to reduce the borehole friction and ensure reaching desired targets within defined accuracy.;This dissertation aims to extend the horizontal section and push the drilling capabilities near their limits without taking undue risks with the drilling system. These risks include stuck pipe, drillstring wear, and fatigue. This objective will be achieved by [1] calculating accurate measurements of borehole positions [true vertical depth, northing and easting], [2] calculating truer measures of wellbore tortuosity and geometric torsion that define the shape and the undulation of the borehole, and [3] predicting accurate measurements of drillstring to borehole friction forces from torque and drag [T&D] models.;The novelty of the proposed models is the ability to estimate more realistic bending effects, accurately predict the contact forces between the drillstring and the wellbore, and solve T&D parameters from surface to total depth in reasonable time using standard engineering computers.;The current 3D borehole trajectory model based on the minimum curvature method [MCM] tend to mathematically smoothen the wellpath. This is due to the assumption that the borehole trajectories are composed of constant curvature arcs. This assumption creates an artificial low tortuosity expressed as dogleg severity [DLS] which leads to the miscalculation of borehole positions, and generating unreliable predictions of T&D.;;Today's T&D models are either based on the assumption of continuous drillstring to wellbore contact [the soft-string model] or intermittent contact due to drillstring stiffness [the stiff-string model]. In both cases, the bending parameter, the change in the rate of curvature and the geometric torsion in the T&D equilibrium equations are nil, because the wellbore trajectory is based on the MCM.;In the scope of this study, a non-constant curvature trajectory model, the Advanced Spline-Curves [ASC] borehole trajectory model, has been developed to overcome these limitations. The principal method proposed using the spline-curves does not make the potentially unrealistic assumption of a constant curvature arc between survey measurements. It provides realistic results and accurately calculates the spatial course of the wellpath. This model is straight-forward and has the robustness and flexibility to calculate complex 3D wellbore trajectories. Based on this non-constant curvature 3D borehole trajectory model, an extended stiff-string 3D T&D model [the ASC 3D T&D model] is developed. This model includes the geometric torsion, the wellbore curvature, the change in the rate of wellbore curvature and the drillstring bending stiffness in its equilibrium equations.;Various applications of the ASC borehole trajectory model and the ASC 3D T&D model are presented, and their results have been validated using field cases with real-time data. The ASC borehole trajectory model has been validated using two methodologies: [a] five horizontal wells with actual survey data recorded at one survey per foot using the high resolution continuous gyroscopic [HRCG] survey tool and [b] two synthetic wellbore examples of known trajectory values. The ASC 3D T&D model has been validated using field cases with real-time forces that define T&D measured at the surface by comparing two methodologies: [a] a semi-analytical approach -- pseudo-high resolution [PHR] survey data generation from the ASC borehole trajectory model at one survey per foot as an input in current industry-approved T&D software, and [b] the ASC 3D T&D model compared to actual drilling data.;The calculated borehole trajectory utilizing the ASC model guarantees curvature continuity along the entire wellpath with significant improvement in wellbore positioning and tortuosity as compared to MCM. This allows the introduction of the change in the rate of curvature and the geometric torsion measurements. The calculated T&D outputs from the ASC 3D T&D model provide a more accurate view of the drilling conditions downhole, including the downhole weight and torque on bit.
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机译：延伸钻进[ER]钻探是指定向钻探到距钻机水平距离[水平偏离]很大的给定地质目标。近年来，随着井眼水平段平均长度的不断扩大，执行复杂的ER操作的能力变得越来越重要。钻这些复杂的井，无论是要达到远离现有设施的储量，还是为了生产和储层管理的优势而暴露储层段，都需要进行准确的规划以减少井眼摩擦并确保在规定的精度内达到预期的目标。水平部分，将钻探能力推到极限附近，而不会给钻探系统带来不必要的风险。这些风险包括管道卡住，钻柱磨损和疲劳。通过[1]计算井眼位置的准确测量值（真实的垂直深度，北向和东向），[2]计算确定井眼的形状和起伏的井眼曲折度和几何扭转的更真实的量度，以及[ 3]通过扭矩和阻力[T＆D]模型预测钻柱对钻孔摩擦力的准确测量值；所提出的模型的新颖性在于能够估算出更真实的弯曲效果，准确预测钻柱与井眼之间的接触力的能力，以及使用标准工程计算机在合理的时间内解决从表面到总深度的T＆D参数。；基于最小曲率方法[MCM]的当前3D井眼轨迹模型倾向于在数学上平滑井道。这是由于假设井眼轨迹由恒定曲率弧组成。这种假设会造成人为的低曲折度，表现为狗腿严重程度[DLS]，这会导致井眼位置计算错误，并产生对T＆D的不可靠预测。；如今的T＆D模型要么基于连续钻柱与井筒接触[ -弦模型]或由于钻柱刚度而导致的间歇性接触[stiff-string model]。在两种情况下，T＆D平衡方程中的弯曲参数，曲率变化率和几何扭转均为零，因为井眼轨迹基于MCM。在本研究范围内，非恒定曲率为了克服这些局限性，开发了先进的样条曲线（ASC）井眼轨迹模型。使用样条曲线提出的主要方法并没有对测量之间的恒定曲率弧线做出可能不切实际的假设。它提供了现实的结果，并准确计算了井道的空间路线。该模型简单明了，具有计算复杂的3D井眼轨迹的鲁棒性和灵活性。基于此非恒定曲率3D钻孔轨迹模型，开发了扩展的刚性弦3D T＆D模型[ASC 3D T＆D模型]。该模型在其平衡方程中包含了几何扭转，井眼曲率，井眼曲率变化率和钻柱抗弯刚度。提出了ASC井眼轨迹模型和ASC 3D T＆D模型的各种应用，并给出了其结果已使用具有实时数据的现场案例进行了验证。 ASC井眼轨迹模型已使用两种方法进行了验证：[a]使用水平连续陀螺仪[HRCG]测量工具每英尺进行一次脚踏测量时记录的实际勘测数据的五个水平井，以及[b]已知轨迹的两个合成井眼示例价值观。 ASC 3D T＆D模型已经通过使用具有实时力的现场案例进行了验证，该案例通过比较两种方法来定义在地面测量的T＆D：[a]半分析方法-伪高分辨率[PHR]从ASC钻孔轨迹模型每英尺一次测量，作为当前行业认可的T＆D软件的输入，[b] ASC 3D T＆D模型与实际钻探数据进行比较。；利用ASC模型计算出的钻孔轨迹可确保整个方向的曲率连续性与MCM相比，井径在井眼定位和曲折度方面有显着改善。这允许引入曲率变化率和几何扭转测量值。通过ASC 3D T＆D模型计算出的T＆D输出可提供更准确的井下钻井条件视图，包括井下重量和钻头扭矩。
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