温差变化对套管变形影响规律研究  

Influences of Temperature Difference Variation on Casing Deformation

作　　者：张楠 郭勇 李爽 楚恒智 穆总结 孙维国 王镇全[2] Zhang Nan;Guo Yong;Li Shuang;Chu Hengzhi;Mu Zongjie;Sun Weiguo;Wang Zhenquan(Research Institute of Engineering Technology,PetroChina Xinjiang Oilfield Company;China University of Petroleum(Beijing);China University of Petroleum(Beijing)at Karamay)

机构地区：[1]中国石油新疆油田分公司工程技术研究院 [2]中国石油大学(北京) [3]中国石油大学(北京)克拉玛依校区

出　　处：《石油机械》2023年第6期83-88,96,共7页China Petroleum Machinery

基　　金：国家自然科学基金项目面上项目“基于井底形状的PDC钻头切削力学模型研究”(51874327);国家自然科学基金项目面上项目“流量-转速耦合作用下液力离合导向钻井控制机理研究”(52274017);新疆维吾尔自治区杰出青年科学基金项目“多元复合冲击钻井提速机理研究”(2021D01E23)。

摘　　要：套管变形已成为制约页岩油气发展的重要因素,不仅影响了储层开发进程,而且降低了油气井产量。为此,采用数值模拟的方法,通过温压耦合效应对套管应力的影响分析来研究温差变化对套管变形的影响规律。研究结果表明:压裂液注入温度比注入排量对套管应力的影响程度更高;在不同水泥环形态下,当管壁处水泥环出现缺失时,温降引起的套管应力增幅(30 MPa以下)较小,而其他部位在水泥环缺失或水泥环完整的情况下,应力增幅(70~90 MPa)较大,这种现象最终导致套管应力对水泥环形态的敏感度降低;压裂时温度影响套管应力的主要方式是套管内的热应力。所得结论可为页岩油气井现场施工中套管变形问题的分析提供理论指导。Casing deformation has become a key restraint on the development of shale oil and gas.It impacts the recovery progress of the shale resources and also decreases well production.Through numerical simulation,the influences of temperature-pressure coupling on casing stress were analyzed to understand how temperature difference variation affects casing deformation.The results show that the fracturing fluid injection temperature has a greater influence on casing stress than the injection rate.Under different cement sheath shapes,when the cement sheath is absent at the casing wall,the casing stress increase caused by temperature drop is small(<30 MPa);when the cement sheath is missing or complete at other positions,the temperature drop triggers greater stress increase(70~90 MPa).This phenomenon may ultimately lead to a lower sensitivity of the casing stress to the cement sheath shape.During fracturing,the casing stress affected by temperature is mainly the thermal stress in the casing.The research findings provide a theoretical guidance for analyzing the casing deformation during field operations of shale oil and gas wells.

关 键 词：页岩油气井 套管变形 温压耦合 应力分布 水泥环形态 压裂液 

分 类 号：TE931[石油与天然气工程—石油机械设备]