底部钻具组合力学行为的钻头边界效应研究

STUDY ON THE BIT BOUNDARY EFFECT OF BHA MECHANICS

宋执武 高德利

Song Zhiwu Gao Deli

石油大学, 北京昌平 102200

University of PetroleumBeijing

通过对钻头处受力情况的深入分析,否定了以前在分析底部钻具组合时,将钻头处的边界条件看作铰支 (即弯矩为零)的一惯做法,提出了应先将钻头处看作是固支 (即转角为零),只有当弯矩达到一定值时,才能出现转角的新观点,并给出了计算弯矩最大值的公式,通过算例对比了 2种处理方法的差别。

In mechanical analysis of the bottom hole assembly, the boundary condition at the bit has been taken as an articulated support, i.e., the bending moment is zero degree. A totally new concept is proposed in this paper, which looks the bit as an immovable support, i.e., the corner is zero. It points out that only when the bending moment reaches a certain value that the corner appears. The formula for calculating the maximum bending moment is also presented, and examples are given to compare the differences between the two methods.

10.3969/j.issn.1000-7393.2001.02.012