悬杆线井眼轨道设计方法

Method of suspender line trajectory design

基于弹性杆力学模型建立了悬杆线井眼轨道设计方法,对比了悬杆线轨道在降摩减扭等方面的优势,分析了悬杆线轨道降摩减扭效果的主控因素及其影响规律。研究表明,相对于常规轨道,悬杆线轨道在一定的参数区间内能够有效降低摩阻、扭矩,相对于悬链线轨道,悬杆线轨道具有更多的可控参数。影响悬杆线轨道降摩减扭效果的主要因素有摩擦系数、造斜点至靶点的水平距离和垂直距离、悬杆段起始点井斜角,摩擦系数、悬杆段起始点井斜角越大,降摩减扭效果越差;当造斜点至靶点的水平距离和垂直距离均超过3 000 m且两者比值接近1.5时,悬杆线轨道的降摩减阻效果最为理想,滑动钻进摩阻最大可降低60%,旋转钻进扭矩最大可降低40%,在深层大位移井中有独特的应用前景。图8表6参28。

Based on the mechanical model of an elastic rod, a new trajectory design method was established. The advantages of the suspender line trajectory in reducing drag and torsion were compared, and the main controlling factors of drag and torque and their influence rules were analyzed. Research shows that the suspender line trajectory reduces drag and torque more effectively than the conventional trajectory in a certain parameter interval and has more controllable parameters than that of the catenary trajectory. The main factors affecting the drag reduction and torque reduction of the suspender line trajectory include the friction coefficient, vertical distance, horizontal distance, and deviation angle at the initial point in the suspended section. The larger the friction coefficient and deviation angle, the less the drag reduction and torque reduction. The suspender line trajectory has the best drag reduction effect when the horizontal and vertical distances are more than 3000 m and the ratio is close to 1.5. The drag in sliding drilling can be reduced up to 60%, and the torque in rotary drilling can be reduced by a maximum of 40%. Therefore, the trajectory design of the suspender line has unique application prospects in deep extended-reach wells.