在以往对钻柱稳定性的研究中 ,人们对受压段钻柱的稳定性问题给予了足够的重视 ,而对受拉段钻柱稳定性的研究则明显不足。钻柱属于细长柔性杆件 ,大部分钻柱在工作时处于受拉状态。在旋转钻井作业中 ,当钻柱较长且转速与拉力存在某种关系时 ,钻柱受拉段也会发生屈曲变形。考虑到垂直井中钻柱受拉段在旋转时的转动效应 ,建立了顶部悬挂、受分布浮重作用的旋转细长钻柱的分岔微分方程。通过对方程的数值求解 ,得到了相应的分岔值曲线。利用该计算模型可以模拟石油钻井工程中旋转细长钻柱受拉段的工作状态 ,所得结果对钻井作业具有一定的指导意义。 In the past study on the stability of drill string, people pay enough attention to the stability of the drill string in the compression section, while the research on the stability of drill string in the tension section is obviously insufficient. The drill string is an elongated, flexible rod with most of the drill string under tension during work. In rotary drilling operations, when the drill string is long and the relationship between rotation speed and tension exists, the buckling of the drill string will also occur. Considering the rotation effect of the drill string during vertical rotation, the bifurcation differential equation of the rotating slender drill string with top suspension and distributed floating load is established. By solving the equations, the corresponding bifurcation curves are obtained. The calculation model can be used to simulate the working condition of the rotating elongated drill string tensioning section in the oil drilling project. The obtained results are of guiding significance for the drilling operation.