论文部分内容阅读
考虑钻柱的扭转效应和接触摩擦,用有限元法建立了整体钻受力分析的三维准静力学模型和空间多向接触摩擦间隙元。用修正的牛顿迭代法进行迭代运算和用近似梯度增量法修改载荷增量,并对钻柱与井壁的接触摩擦和钻柱变形进行了分析计算。现场实验证明本文提出的理论和模型用于井眼轨迹跟踪预测结果与钻后实测结果符合很好,可作为定向井钻柱受力分析以及井眼轨迹设计和预测的一种基础理论和实用方法。
Considering the twisting effect and contact friction of the drill string, a three-dimensional quasi-static model and a space multidirectional contact frictional gap element for the overall drilling force analysis were established by finite element method. The modified Newton iterative method is used to perform iterative calculation and the approximate gradient incremental method is used to modify the load increment. The contact friction between the drill string and the borehole wall and the drill string deformation are analyzed and calculated. Field experiments show that the theory and model proposed in this paper are in good agreement with the measured results of wellbore trajectory tracking and can be used as a basic theory and practical method for the stress analysis of wellbore and the design and prediction of wellbore trajectories. .