摘要
页岩气水平井多级压裂过程中套管变形(套变)现象显著,降低了储层动用率,增加了压裂成本。综合国内外学者对该问题的研究成果,对比分析了国内外页岩气水平井套管变形现状,以长宁-威远、泸州、威荣区块的套管变形数据为基础,总结了套管变形问题在时间、空间、形态上的分布规律。讨论了套管及水泥环类型、固井质量、压裂及射孔参数、热应力等工程因素和储层非均质性、储层滑移等地质因素对套管变形的影响。调研分析结果认为,工程因素会使套管应力增加,但不易造成套管变形,而地质因素中多级压裂诱发天然裂缝和断层活化导致的储层滑移是套管产生较大变形的主控因素。针对该问题总结梳理了优选套管及水泥环参数、提升固井质量、优选压裂及射孔参数、优化井眼轨迹、控制储层滑移等多种控制方法,并提出了需提高对地层的认识和储层滑移预测精度等方面的建议。研究成果可为压裂过程中套管完整性设计及控制提供参考。
Significant casing deformation(CD)occurs during multi-stage fracturing of shale gas horizontal wells,which reduces the ratio of recovered reservoirs and increases operation costs.Based on a comprehensive review of global research on this issue,a comparative analysis of the current status of casing deformation in shale gas horizontal wells was conducted.With the casing deformation data from Changning-Weiyuan,Luzhou,and Weirong blocks,the distribution patterns of casing deformation in terms of time,space,and morphology were summarized.The influences of engineering factors such as casing and cement sheath types,cementing quality,fracturing and perforation parameters,and thermal stresses,as well as geological factors such as reservoir heterogeneity and reservoir slip,on casing deformation,were analyzed.The analysis results indicate that while engineering factors can increase casing stresses,they are unlikely to cause casing deformation.Among geological factors,reservoir slip induced by natural fractures and faults activated during multi-stage fracturing is the main controlling factor leading to significant casing deformation.To address this issue,various control methods were summarized,including optimizing casing and cement sheath parameters,improving cementing quality,selecting appropriate fracturing and perforation parameters,optimizing wellbore trajectory,and controlling reservoir slip.Additionally,it was proposed to enhance the understanding of formations and improve prediction accuracy of reservoir slip.The research findings provide references for casing integrity design and control during the fracturing process.
作者
尹奥博
李军
连威
张辉
YIN Aobo;LI Jun;LIAN Wei;ZHANG Hui(Karamay Campus,China University of Petroleum(Beijing),Karamay 834000,Xinjiang,China;China University of Petroleum(Beijing),Changping 102249,Beijing,China)
出处
《新疆石油天然气》
2025年第1期50-60,共11页
Xinjiang Oil & Gas
基金
国家自然科学基金青年基金项目“页岩气井多级压裂诱发断层滑移量化计算模型与套管变形控制方法研究”(52204018)。
关键词
页岩气
套管变形
水平井
储层滑移
主控因素
四川盆地
shale gas
casing deformation
horizontal well
reservoir slip
main controlling factor
Sichuan Basin
