盐岩蠕变特征对井筒形变量的影响规律  

Influence of Creep Characteristics of Salt Rock on Wellbore Deformation

作　　者：闫炎 蔡萌 马文海 张晓川 韩礼红 刘永红[3] YAN Yan;CAI Meng;MA Wenhai;ZHANG Xiaochuan;HAN Lihong;LIU Yonghong(State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials,CNPC Tubular Goods Research Institute,Xi’an,Shaanxi 710077,China;Production Engineering Research Institute,CNPC Daqing Oilfield Company,Daqing,Heilongjiang 163458,China;College of Mechanical and Electrical Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China)

机构地区：[1]中国石油集团工程材料研究院有限公司,陕西西安710077 [2]中国石油集团大庆油田分公司采油工程研究院,黑龙江大庆163458 [3]中国石油大学(华东)机电工程学院,山东青岛266580

出　　处：《西安石油大学学报（自然科学版）》2024年第3期42-49,共8页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：中国石油天然气集团有限公司科学研究与技术开发项目“油气井套损评价与修复关键技术研究”(2021DJ2705);“井筒完整性关键理论与控制技术”(2021DJ4403)。

摘　　要：针对盐岩地层普遍出现的套损现象,借助三轴岩石力学实验对取自川东北油气田某地层段盐岩的蠕变特性进行了实验研究。基于实验结果,构建了可描述盐岩的衰减蠕变阶段和稳态蠕变阶段特征的非定常盐岩蠕变模型,基于该盐岩蠕变模型计算深部盐岩地层蠕变过程中井筒径向位移的变化,计算结果显示井筒内压能有效地降低盐岩内壁的蠕变位移,而地层水平主应力和上覆地层压力可增大地层的偏差应力,从而增加盐岩内壁的蠕变位移。为避免盐岩蠕变造成套管变形,在水泥中添加空心陶瓷颗粒可有效降低水泥的弹性模量,使得水泥环能充分吸收地层径向蠕变给井筒系统增加的应变能,进而降低对套管的挤压作用,减小套变风险,形成油气井工程上一种新型套管止变技术方法。Aiming at casing damage in salt rock,the creep characteristics of the salt rock were studied by means of triaxial rock mechanics experiments.An unsteady salt rock creep model which can describe the attenuation creep stage and steady-state creep stage of the salt rock is established based on the the experiment results.The radial displacement of wellbore in the creep process of deep salt rock is calculated based on the model.The calculation results show that the internal pressure of the wellbore can effectively reduce the creep displacement of the inner wall of the salt rock wellbore,while the horizontal principal stress and overlying pressure of the formation can increase the deviation stress of the formation,thereby increasing the creep displacement of the salt rock wellbore wall.In order to avoid casing deformation,the elastic modulus of cement is effectively reduced by adding hollow ceramic particles to the cement,thereby reducing the extrusion effect on the casing,reducing the risk of casing deformation,and forming a new type of casing deformation prevention technology for oil and gas wells.

关 键 词：盐岩蠕变 套管变形 地层滑移 水泥环 径向位移 

分 类 号：TE931.2[石油与天然气工程—石油机械设备]