有限元法在钻铤螺纹结构优化中的应用

Application of finite element method in the structure optimization of drill collar thread

胡大梁 陈平 朱礼平

Hu Daliang Chen Ping Zhu Liping

西南石油大学石油工程学院, 四川成都 610500

Petroleum Engineering Institute of Southwest Petroleum University, Chengdu 610500

在空气钻井中, 经常发生由钻铤螺纹断裂引起的下部钻具组合失效事故。在现场资料分析基础上, 运用UG软件建立了钻铤螺纹联接模型, 然后通过有限元软件分析了钻铤螺纹应力分布, 得出了钻铤螺纹在不同工况、结构条件下的等效应力分布情况, 并对钻铤螺纹结构优化设计过程进行了相应说明。通过算例分析, 得出了应力减轻槽的过渡圆角R1=8 mm, R2=15 mm为最优值。

The bottom hole assembly failure caused by drill collar thread usually occurs during the air drilling. On the basis of field resources analysis, the drill collar thread model is created by UG, and analyzed the thread stress under different axial forces by finite element method. The structure optimization design process of drill collar is described in the paper. It is summarized that R1=8 mm, R2=15 mm is the optimum transition radius of stress relief groove.