压裂工况下近井筒地应力及套管载荷分布规律研究

Study on the Distribution Law of Near-Wellbore in-situ Stress and Casing Load under Fracturing Conditions

赵欢 李玮 唐鹏飞 王晓 张明慧 王剑波

ZHAO Huan LI Wei TANG Pengfei WANG Xiao ZHANG Minghui WANG Jianbo

东北石油大学石油工程学院, 黑龙江大庆 163318 油气钻完井技术国家工程研究中心, 黑龙江大庆 163318 中国石油大庆油田有限责任公司采油工程研究院, 黑龙江大庆 163453 中石化新疆新春石油开发有限责任公司, 山东东营 257000

School of Petroleum Engineering, Northeast Petroleum University, Daqing, Heilongjiang, 163318, China National Engineering Research Center of Oil & Gas Drilling and Completion Technology, Daqing, Heilongjiang, 163318, China Oil Production Engineering Research Institute, PetroChina Daqing Oilfield Co., Ltd., Daqing, Heilongjing, 163453, China Sinopec Xinjiang Xinchun Petroleum Development Co., Ltd., Dongying, Shandong, 257000, China

为了研究水力压裂工况下套管损坏机理及套管载荷影响因素，开展了储层岩石力学参数测试，建立了套管–水泥环–地层–裂缝的多场耦合有限元分析模型，分析了水力压裂扩展时近井筒地应力及套管载荷的分布规律及影响因素。研究结果表明，储层中天然裂缝的存在引起水力裂缝的非均匀扩展，套管承受非均匀载荷；当储层地应力差增加、弹性模量降低时，近井筒地应力及套管载荷增加；天然裂缝数量及天然裂缝分布形态对近井筒地应力及套管载荷的影响较为复杂。研究结果为页岩储层优化固井设计及压裂设计、减少套管损坏问题提供了理论依据。

In order to study the casing damage mechanism and the influencing factors of casing load under hydraulic fracturing conditions, rock mechanics tests were carried out, and a multi-field coupled finite element analysis model of casing, cement sheathe, formation, and fracture was established. Distribution law and influencing factors of near-wellbore in-situ stress and casing load under hydraulic fracturing propagation were analyzed. The results showed that the natural fractures in the reservoir caused the non-uniform propagation of hydraulic fractures, and the casing was subjected to a non-uniform load. The in-situ stress difference increased and the elastic modulus decreased while the near-wellbore in-situ stress and casing load increased. The influence of the natural fracture number and the distribution pattern of natural fractures on the near-wellbore in-situ stress and casing load were complicated. The research results provide a theoretical basis for optimizing the cementing design and fracturing design of shale reservoirs and reducing casing damage.

国家自然科学基金项目“万米深井PDC钻头冲击破岩机理及提速方法研究”（编号：52274005）、东北石油大学人才引进科研启动项目“页岩油储层水平井压裂复杂裂缝控制机制研究”（编号：13051202008）联合资助

https://doi.org/10.11911/syztjs.2023092