斜井中泥页岩井眼稳定性研究

STUDY ON SHALE STABILITY IN INCLINED WELL

泥页岩井眼稳定是由力学与化学两方面因素共同作用的结果。借助于井壁处有效应力的变化 ,将泥页岩与钻井液相互作用时页岩水化所产生的力学效应与纯力学效应结合起来 ,建立了斜井井眼稳定的力学、化学耦合模型 ,运用该模型可计算出保持井眼稳定的合理钻井液密度 ,并结合实例对该模型进行了验证与简要的分析。

Shale stability is influenced by both mechanics and chemistry factors mutually. A model for wellbore stability in inclined wells is established based on the changes of effective stress near the borehole area, combining the mechanics effect produced by shale hydration with pure mechanics effect, and coupling of mechanics and chemistry factors. This model can be used to determine the suitable mud densities for holding the wellbore stability, and it is further testified and analyzed with examples.\;