考虑层理性时造斜段井壁坍塌行为研究  

Wellbore Collapse Behavior in Inclined Section Considering Stratum Rationality

作　　者：陈颖超 CHEN Ying-chao(Department of Petroleum Engineering,Hebei Petroleum University of Technology,Chengde 067000,Hebei,China)

机构地区：[1]河北石油职业技术大学石油工程系,河北承德067000

出　　处：《承德石油高等专科学校学报》2023年第5期29-33,共5页Journal of Chengde Petroleum College

基　　金：河北省高等学校科学技术研究项目(高尚堡区块井筒倾斜段岩屑运移规律及清岩工具优化研究)。

摘　　要：经过对层理发育的页岩地层造斜钻进实践调研得出,井壁不稳定问题严重影响钻井速度和质量。以X页岩气田区块为研究对象,进行井壁垮塌行为研究。综合分析该工区地质特征、造斜段井壁失稳情况,得出井壁坍塌是由力学因素导致的。在分析倾斜井壁围岩应力状态的基础上,建立岩石的强度破坏数学模型,在考虑弱面倾角的情况下,计算地层坍塌压力变化规律,得出不同井眼方向、井斜与井壁垮塌的关系,考虑到页岩气储层特性,建议提高钻井液封堵能力,防止造成井壁失稳。Through the investigation on practice of deviation drilling in shale formation with devel-oped bedding,it is concluded that the problem of wellbore instability seriously affects the drilling speed and quality.This paper takes X Shale Gas Field Block as the research object to study the well-bore collapse behavior.By comprehensively analyzing the geological characteristics of the working area and the wellbore instability in the inclined section,it is concluded that the wellbore collapse is caused by mechanical factors.On the basis of analyzing the stress state of the surrounding rock of the inclined shaft wall,a mathematical model of rock strength failure is established.Considering the weak plane inclination,the variation law of formation collapse pressure is calculated,and the rela-tionship between different borehole directions,well inclination and wellbore collapse is obtained.In view of the characteristics of shale gas reservoir,it is suggested to improve the plugging ability of drilling fluid to prevent wellbore instability.

关 键 词：井壁坍塌 强度破坏 弱面倾角 封堵能力 

分 类 号：TE243[石油与天然气工程—油气井工程]