利用绕层固井装置提高页岩气井套管完整性  

Study on improvement of casing integrity by using a bypass cementing device in shale gas wells

作　　者：席岩 李军[2] 汪伟 高德伟 连威[2] XI Yan;LI Jun;WANG Wei;GAO Dewei;LIAN Wei(College of Architectural and Civil Engineering of Beijing University of Technology, Beijing 100124, China;College of Petroleum Engineering of China University of Petroleum(Beijing), Beijing 102249, China;Sichuan Changning Natural Gas Development Company Limited, Chengdu 615056, China)

机构地区：[1]北京工业大学建筑工程学院,北京100124 [2]中国石油大学(北京)石油工程学院,北京102249 [3]四川长宁天然气开发有限责任公司,四川成都615056

出　　处：《中国石油大学学报（自然科学版）》2021年第3期82-87,共6页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金联合基金重点项目(U1762211);国家自然科学基金面上项目(51674272);国家自然科学基金青年基金项目(52004013)。

摘　　要：针对页岩气井多级压裂过程中断层滑移实际,设计一种可绕套变地质风险段的固井装置,采用Shell-Solid耦合方法建立套管剪切变形数值模型,计算剪切变形后套管内径沿轴向变化,并对比分析不同工程条件下常规固井与绕层固井的保护效果。结果表明断层滑移后套管最小内径出现在套管滑移面附近,模拟形态与多臂井径和铅模测量形态较为一致;断层滑移后岩性界面处套管变形较为显著,随着滑移地层弹性模量的增加,套管内径缩径量不断增加;同等条件下采用绕层固井方法比常规固井套管缩径量降低34.6%,效果明显优于增加套管壁厚;扩径后使用该装置套管缩径量降低43.2%。A bypass cementing device was designed to mitigate the influence of casing shear deformation.A numerical model using shell-solid coupling method was developed to calculate the diameter variation of the production casing along the wellbore,and the performance of the device on casing protection was analyzed by comparing the conventional and bypass cementing.The results show that the minimum casing diameter appeared at near the interface of the casing and cement slip.The casing diameter shrinkage can be reduced by 34.6%using the bypass method in comparison with the conventional method under the same conditions,which was obviously better than increasing the casing wall thickness.After wellbore enlargement,the casing diameter shrinkage using the bypass device can be reduced by 43.2%.The research results can provide a reference for the design and control of casing integrity during multistage fracturing of shale gas wells.

关 键 词：固井 地层滑移 剪切变形 数值模拟 

分 类 号：TE21[石油与天然气工程—油气井工程]