摘要
页岩气井水力压裂施工会使套管产生剪切和挤压变形从而失效,严重影响页岩气的开采,造成巨大的经济损失。因此基于abaqus软件,建立水力压力作用下的地层-裂缝-水泥环-套管有限元模型。通过研究水力压裂过程中天然裂缝滑移与套管变形情况,分析页岩气开采过程中套管失效的原因。研究表明:水力压裂会导致天然裂缝发生滑移,从而使套管产生剪切变形,变形位置多位于套管与裂缝的相交处,且套管变形程度随裂缝滑移量的增加而增大;水平最小主应力越大,对套管变形影响越大;施工排量越大,套管变形量越大;天然裂缝与套管夹角越小,套管越容易发生变形,当天然裂缝的角度小于45°时,套管极易产生变形。本研究可为防止天然裂缝滑移引起的套管剪切变形提供参考。
The hydraulic fracturing of shale gas wells will cause the casing to be sheared and squeezed and eventually fail,which will seriously affect the production of shale gas and cause significant economic losses.Therefore,based on the Abaqus software,this paper establishes a finite element model of the formation,fracture,cement ring and casing under hydraulic pressure.By studying the natural fracture slippage and casing deformation during hydraulic fracturing,the reasons for casing failure in shale gas production are analyzed.It is shown that hydraulic fracturing will cause natural fractures to slip,which will cause the casing to produce shear deformation.The deformation position is mostly located at the intersection of the casing and the crack,and the degree of casing deformation increases with the increase of crack slip.The greater the horizontal minimum principal stress,the greater the impact on casing deformation.The greater the construction displacement,the greater the casing deformation.The smaller the angle between the natural crack and the casing,the more likely it is to deform the casing.When it is less than 45°,the casing is easily deformed.This study can provide a reference for preventing casing shear deformation caused by natural fracture slippage.
作者
代清
林颢屿
陈春宇
张伟
麦洋
DAI Qing;LIN Haoyu;CHEN Chunyu;ZHANG Wei;MAI Yang(CNPC Chuanqing Drilling Engineering Company Limited,Chengdu 610056,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China;Oil and Gas Technology Research Institute of Changqing Oilfield Company,Xi'an 610112,China;Oil Production Technology Research Institute of the Third Oil Production Plant of Changqing Oilfield,Yinchuan 750000,China)
出处
《机械设计与研究》
CSCD
北大核心
2022年第3期118-121,126,共5页
Machine Design And Research
基金
四川省重点研发项目(21ZDYF3109
21SYSX0054)
中国石油-西南石油大学创新联合体科技合作项目:页岩气水平井套损机理及治理技术专题(2020CX040204)。
关键词
水平井
套管失效
剪切变形
天然裂缝滑移
套管有限元分析
shale gas horizontal well
casing failure
shear deformation
natural fracture slip
casing finite element analysis
