不扩孔径向水平井钻管转向仿真研究

针对177.8 mm套管内部空间尺寸的约束条件,建立转向器弯曲导向滑道及钻管模型,利用ANSYS软件,对钻管通过转向器滑道的转向过程进行有限元仿真研究。仿真结果表明:在钻管弯曲转向时钻管弯曲内侧更易发生失稳;转向器滑道曲率变化率是个非常重要的参数,钻管应力、截面变形、钻管阻力都与其有关,为了使钻管以低应力、较为安全的状态通过转向器,减小滑道轨迹的曲率变化率是必要的方式;材料为X的钻管可以安全穿过滑道,钻管转向后可以沿滑道水平钻进,钻管变形保持在许可范围内,能够满足径向水平井的钻进要求。

Simulation on drill pipe's bending in non-reaming radial horizontal well

For constrains of internal space in the casing with the diameter of 177.8 mm,a slide way guided by the steering gear as well as a drill pipe model was established to make finite element simulation research for the steering process with ANSYS software.The results show that the inner side of the bending drill pipe destabilization occurs easily in steering.The velocity of steering gear curvature variation is an important parameter,and the drill pipe stress,section deformation and drill pipe resistance are correlated with it.It’s necessary to decrease the velocity of slide track curvature variation in order to make the drill pipe pass through the steering gear in a low stressful and safe sate.The drill pipe made of X material can pass through the slide way safely and keep along the horizontal direction after steering.In this process,the deformation of the pipe is maintained within the limits so that it can meet the requirements of radial horizontal well drilling.