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

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。

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.