On the basis of energy method, the possibility of drill stem buckling in inclined straighthole is studied.
本文应用虚位移原理，在充分考虑钻柱所处的特殊环境的基础上，考察了斜直井眼中钻柱屈曲的可能性。
2
The on-site tests of 5 wells showed that the stiffness of lower drill pipe assembly was increased to control deviation in the straighthole.
经现场5口井试验表明，不弯曲钻铤能够起到增大下部钻具组合刚度，控制直井段井斜的作用；
3
It also figures out that the wellbore stability of directional well in the West of Sichuan Basin will be much better than the straighthole with the increasing of the deviation and relative azimuth.