圆柱拟合法在描述斜井空间形态中的应用

APPLICATION OF COLUMN MATCHING METHOD IN DESCRIPTIONS OF SPECIAL SHAPE OF DEVIATED WELLS

龚伟安

Gong Wei’an

长庆石油勘探局钻采工艺研究院

应用圆柱拟合方法建立了斜井抛物线剖面空间曲线的参数方程,给出了井眼曲率及挠率的计算公式。文中从微分几何原理出发,证明了不存在Lubinski提出的"狗腿用平面",因而过去以此为基础的井下钻具组合和套管扶正器的三维分析都不是精确解。并指出,目前各种井眼曲率计算方法都是近似的,都低估了井眼实际弯曲的严重程度。为提高井眼质量,建议在制定技术法规时,严格控制斜井的方位漂移率。最后建议在水平井及斜井的有关技术文件中,增加一幅井眼空间轨迹的立体图,以便给钻井作业者和采油作业者一个形象的、生动逼真的井眼轨迹的空间形态。

The parameters equation of parabolic section special curves of deviated wells were set up applying the column matching method and calculation equations of well curvature and bending deflection. Based on the principles of differential geometry, the "Foot plane of dog-leg" raised by Lubinski was demonstrated not being existent. Therefore the three-dimensional analysis of drill pipe assembly and casing stabilizers deduced are not accurate. The author considered that the different calculation methods present are all approximate because of their underestimation of the degree of the practical deviation of the well. The paper recommends taking a strictly controlled value of direction drift of deviated well in standardization of technical specifications and provision with a special trail of borehole to the drilling and production operation contractors.

10.3969/j.issn.1000-7393.1997.03.003