钻井液密度与井壁围岩破坏的关系

CORRELATION BETWEEN BOREHOLE SURROUNDING ROCK DAMAGE AND DRILLING FLUID DENSITY

张广清 陈勉

Zhang Guangqing Chen Mian

石油大学, 北京昌平 102249

University of Petroleum

钻井液密度对井壁围岩的稳定性具有重要的作用。通过有限元分析,根据Drucker-Prager破坏准则,模拟了井壁剪切破坏的连续过程,并且给出了井壁围岩破坏尺寸与钻井液密度的关系,对于分析钻井液密度对井壁围岩破坏区域的影响提供了定量依据。计算出的模拟规律与现场观测和实验室内试验结果基本一致。

The reasonable drilling fluid densities are vitally important for the stability of borehole surrounding rock. Its continuous process of borehole shearing damage is simulated based on the principle of Drucker-Prager and through the way of finite element analysis, and the correlation between the damaging scale and the density of drilling fluid is also presented. The simulating tendency is basically concordant with the field condition and the laboratory testing result, and this study provides a quantitative backup for analyzing the influence of drilling fluid density on the damaging area of borehole surrounding rock.

10.3969/j.issn.1000-7393.2002.03.005