摘要
运用定向井或水平井眼中钻柱的有限元分析模型，将钻柱的总量变形分为钻柱相对于井眼轴线的变形和弯曲井眼迫使钻柱产生的初始变形，使复杂的钻柱非线性问题得以简化。通过一口水平井在其增斜段钻柱全氏的受力与变形的计算，可以看出不同载荷条件下，钻柱和井壁的接触状况，以及大钩载荷。用该模型对下部钻具组合进行了非线性分析，将非线性分析结果和线性结果做了比较。对钻柱的摩阻负荷进行了计算，提高了准确性。算例表明结果是合理的，为钻柱及下部钻具组合的力学分析提供了一个新的计算方法。该方法同样适用于套管柱的力学分析。
A finite element model of the drillstring in thedirectional orhorizontal wellbores is pre-sented.The total deformation of the drillstring is divided as deformation related to the axis ofthe wellbore and the initial deformation forced by a curved wellbore.Then the non-linearproblem of the drillstring is sirnplified. The force and deformation along the whole drillstringare computed in a horizontal well with this model. The hook load as well as the contact statebetween the dirllstring and well wall can be obtained. The non-linear analysis of BHAS aredone,their results are compared with the linear results. The results in a whole drillstring areconlpared with those computed in terrns of the length of BHA. Also, the frictional analysisbased on the static analysis of the drillstring is improved due to a consideration of the contactbetween the drillstring and well wall. First computation about the force and deformation ofthe whole drillstring is d0ne. These examples show that the conclusion is reasonable. A newmethod is provided for mechanical analysis of the whole drillstring or BHA. The method pre-sented in the paper is adaptable to the analysis of casing strings also.
出处
《石油学报》
EI
CAS
CSCD
北大核心
1995年第1期118-126,共9页
Acta Petrolei Sinica
关键词
钻柱
有限元
定向井
水平井
井眼
钻井
drillstring mechanic finite element method friction non-linear structure analysis casing string
