含伸缩管的超深高温高压气井完井测试管柱三维力学行为分析  

3D Mechanical Analysis on Completion Testing Tubing String with Expansion Pipe Section for Extra-deep HPHT Wells

作　　者：刘洪涛[1] 沈新普 王克林[1] 沈国阳 刘爽[1] LIU Hongtao;SHEN Xinpu;WANG Kelin;SHEN Guoyang;LIU Shuang(Tarim Oil Branch PetroChina,Korla,Xinjiang 841000,China;China Petroleum University (Huadong),Qingdao,Shandong 266580,China)

机构地区：[1]中国石油塔里木油田分公司,新疆库尔勒841000 [2]中国石油大学(华东),山东青岛266580

出　　处：《石油管材与仪器》2019年第5期59-66,共8页Petroleum Tubular Goods & Instruments

摘　　要：提出了具有伸缩管的完井测试管柱三维有限元力学行为分析数值计算流程,并将其成功用于塔里木油田MJ4井完井测试管柱塑性变形分析。建立的管柱三维有限元模型中考虑了闭合距偏离、并考虑了油管-套管间摩擦接触。分析中考虑了坐封、压裂、放喷三种不同的施工阶段下管柱变形的情况。给出了上述模型在不同压力及温度载荷下的管柱变形及应力分布的数值解,主要包括:1)管柱变形沿全长的分布;2)管柱全长轴向力及Mises等效应力分布;3)伸缩管以下管柱段的变形、应力的大小与分布、及该部分管柱与套管之间的接触力和摩擦力的大小及分布。根据有限元数值计算结果,得到的结论包括以下3个部分:1)在坐封、压裂、放喷三种不同的施工阶段,伸缩管分开处的流体压力会引起比没有伸缩管时相应的轴向应力值更大的轴向应力;2)在给定的MJ4井结构设计及施工压力及温度载荷下,伸缩管以下管柱发生弹性屈曲;3)MJ4井封隔器水力锚下部锚固不佳,导致压裂载荷在油管柱上产生附加载荷,是致使油管柱发生塑性屈曲的因素之一。Workflow for numerical solution to mechanical behavior of completion testing tubing system with 3D finite element method has been proposed. The workflow proposed here was applied to analysis on plastic deformation of completion testing tubular string. 3D finite element model was built for analysis of mechanical behavior of the tubular system. Factors of wellbore trajectory deviation and frictional contact between tube and casing are considered in the model. Loads of packer setting,hydraulic fracturing,and gas production are included. Numerical solutions of stress and displacement distribution along the tubing are presented. Principal results are:1) Displacement distribution along the whole length of tubing. 2) Distribution of axial stress and von Mises stress along the whole length of tubing. 3) Distribution of displacement and stress along the tubing section below expansion pipe,as well as frictional contact stress and frictional force in this section. With reference to the numerical results obtained,the following conclusions are derived:1) For the stages of packer setting,hydraulic fracturing,and gas production,inner pressure at location of expansion pipe will result in bigger value of axial stress than that in the case without expansion pipe. 2) Under the given working loads of pressure and temperature with regular structures as designed for MJ4 well,elastic buckling occurs within the tubing section below expansion pipe. 3) Poor quality of lower hydraulic anchorage of packer results in additional load to tubing,and consequently it is one of the major factors resulting in tubing′s plastic deformation.

关 键 词：完井管柱 测试 高温高压 塑性变形 屈曲 数值模拟 伸缩管 

分 类 号：TE257[石油与天然气工程—油气井工程]