The tensioned collar is not easy being bent, which will increase the pendulum length, and increase its ability to control deviation. 这样受拉钻铤受到了很大的拉力，从而使其不容易弯曲，可增加钟摆段的长度，进而提高了其防斜能力。
Evaluation of formation drill-ability anisotropy has important effect for preventing deviation of straight holes and planning drilling trajectories of directional wells. 地层可钻性各向异性评价在直井防斜以及定向井井眼轨迹控制中具有重要的意义。
