摘要
在钻井过程中裂缝性地层井壁稳定问题突出,传统力学模型难以准确评价井壁失稳机理。为深入研究裂缝性灰岩地层的井壁稳定性,以铜锣峡气田X井为例,利用井壁成像测井图像处理方法提取裂缝形态,建立了三维离散元井壁稳定模型,研究了不同钻井液密度下裂缝井壁的失效和变形。研究表明:在无钻井液支撑时,井壁破坏单元主要集中在水平最小主应力方向上和裂缝与井筒切割位置;在裂缝倾角较大处,井壁位移明显增加,随着钻井液密度的增加,井壁附近的破坏单元数量减少,主要集中在裂缝附近且井壁变形减小;钻井液密度从0提高到1.2 g/cm3时,可以有效增加井壁最小主应力,同时降低最大主应力,使得两者差值减小,井壁稳定性增强。研究结果为裂缝性灰岩地层安全高效钻井提供了重要参考。
During the drilling process,the problem of wellbore stability in fractured formations is prominent,and traditional mechanical models are difficult to accurately evaluate the mechanism of wellbore instability.To deeply study the wellbore stability of fractured limestone formations,taking well X in the Tongluoxia Gas Field as an example,the fracture morphology was extracted by using the wellbore imaging logging image processing method,and a three-dimensional discrete element wellbore stability model was established to study the failure and deformation of the wellbore in fractured formations under different drilling fluid densities.The research shows that when there is no drilling fluid support,the wellbore failure units are mainly concentrated in the direction of the horizontal minimum principal stress and the position where the fractures intersect with the wellbore;at the location with a larger fracture dip angle,the wellbore displacement increases significantly.With the increase of drilling fluid density,the number of failure units near the wellbore decreases,mainly concentrated near the fractures,and the wellbore deformation reduces.When the drilling fluid density increases from 0 g/cm³to 1.2 g/cm³,it can effectively increase the minimum principal stress of the wellbore and simultaneously reduce the maximum principal stress,thereby reducing the difference between the two and enhancing the wellbore stability.The research results provide an important reference for safe and efficient drilling in fractured limestone formations.
作者
石祥超
张琴
卓云
高雷雨
贾熹文
SHI Xiangchao;ZHANG Qin;ZHUO Yun;GAO Leiyu;JIA Xiwen(National Key Laboratory of Oil and Gas Reservoir Geology and Exploration,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Chuandong Drilling Company,CNPC Chuanqing Drilling Engineering Co.,Ltd.,Chongqing 400021,China)
出处
《钻采工艺》
北大核心
2025年第4期27-36,共10页
Drilling & Production Technology
基金
中国石油-西南石油大学创新联合体项目“深井超深井安全高效建井关键基础理论与技术研究”(编号:22020CX040100)。
关键词
裂缝性地层
三维离散元
钻井液密度
井壁稳定
fractured formation
three-dimensional discrete element
drilling fluid density
wellbore stability
