On the contrary, the back welldrillmethod is from bottom to top, which is suitable for the small inclined Angle, but not for the large shaft section.
反井法施工斜井为自下而上进行，适合倾角不大的斜井施工，但不适宜运用于断面较大的斜井。
2
Geostress distribution is used to guide drill track, offering a new method to optimize well track.
应用地应力分布指导钻井轨迹，为井眼轨迹优化提供了新的研究方法。
3
According to the mechanics analysis method of BHA and the real work state of drill string in inclined straight well, a mechanical model of BHA is presented.