井研—犍为筇竹寺页岩气井套变机理及预防措施

Mechanism and Preventive Measures of Casing Deformation in Shale Gas Wells of Qiongzhusi Formation in Jingyan-Qianwei Area

张国东 夏彪 李友培 李曙光 穆轲帆 王治国 卢丽

ZHANGGuodong XIABiao LIYoupei LIShuguang MUKefan WANGZhiguo LULi

中国石化西南油气分公司石油工程技术研究院, 四川 德阳 618000 中国石化西南油气分公司勘探开发研究院, 四川 成都 610041

Petroleum Engineering Technology Research Institute, Southwest Petroleum Branch, SINOPEC, Deyang, Sichuan 618000, China Exploration and Development Research Institute, Southwest Petroleum Branch, SINOPEC, Chengdu, Sichuan 610041, China

井研—犍为地区筇竹寺组粉砂质页岩气资源量巨大，该区目的层埋深较大、地质构造复杂、储层内水平地应力值较高，部分井在压裂过程中出现严重的套管变形，导致丢段，从而严重影响单井产量。基于套管变形失效特征及变形井段共性工程、地质影响因素分析，建立了地层-套管-水泥环压裂数值模拟模型，明确了套管变形机理。基于临界注入压力、地层应力状态及其对应的压裂裂缝状态建立一套套变风险的评估方法，对套变风险进行分级，形成“精细优化+实时预警+三控模式”的均衡压裂防套变技术体系，精细分段，利用微地震监测实时预警，风险段控制规模，排量、运行节奏，应用结果表明，该技术体系能够有效降低套变的发生，为该区效益规模开发提供了技术支撑。

Jingyan-Qianwei Qiongzhusi has a huge amount of silty shale gas resources. The target layer in this area has a large burial depth, complex geological structure, and high horizontal stress values in the reservoir. Some wells experienced severe casing deformation during the fracturing process, resulting in lost sections and seriously affecting single well production. Based on the characteristics of casing deformation failure and the analysis of common engineering and geological influencing factors in the deformed well section, a numerical simulation model of formation casing cement ring fracturing was established to clarify the mechanism of casing deformation. A set of risk assessment methods for casing deformation is established based on critical injection pressure, formation stress state, and corresponding fracturing fracture state. The risk of casing deformation is classified, forming a balanced fracturing and casing deformation prevention technology system of "fine optimization+real-time warning+three control mode". The technology is finely segmented, and real-time warning is used through microseismic monitoring. The risk section controls the scale, displacement, and operation rhythm. The application results show that the technology system can effectively reduce the occurrence of casing deformation and provide technical support for the development of the area's benefit scale.

10.11885/j.issn.1674 5086.2024.12.05.05