基于轴向载荷离散模型的连续管下入性分析  

Analysis on Running Ability of Coiled Tubing Based on Axial Load Discrete Model

作　　者：曹银萍[1,2] 谢凡 冯佳佳 朱文宇 魏文澜 郑杰 Cao Yinping;Xie Fan;Feng Jiajia;Zhu Wenyu;Wei Wenlan;Zheng Jie(Mechanical Engineering College,Xi'an Shiyou University;Xi'an Key Laboratory of Wellbore Integrity Evaluation;Well Test Company of CNPC Xibu Drilling Engineering Company Limited)

机构地区：[1]西安石油大学机械工程学院,陕西省西安市710065 [2]西安市高难度复杂油气井完整性评价重点实验室 [3]西部钻探试油公司

出　　处：《石油机械》2024年第12期1-7,共7页China Petroleum Machinery

基　　金：国家自然科学基金项目“多轮吞吐下CO_(2)注采井完井管柱特殊螺纹接头密封机理研究”(52374039);西安石油大学研究生创新与实践能力培养计划“连续油管井下力学模型建立”(YCS23114125)。

摘　　要：连续管在水平井作业过程中易发生屈曲变形制约其作业深度,为此开展不同井段中连续管轴向载荷对其下入深度的影响研究。通过对井眼轨迹中的关键参数分析构建弯曲段全角平面,并基于软杆模型和构建的全角平面,综合考虑连续管刚性、流体摩阻、井壁接触摩阻和屈曲后的附加接触摩阻,建立了连续管轴向载荷计算模型;通过迭代法并结合屈曲状态分析对某井进行算例分析。分析结果表明:连续管在垂直段与斜直段更容易发生螺旋屈曲;随着摩擦因数由0.10增加到0.35,螺旋屈曲长度增加到1189.19 m,下入深度由4370.00 m减小到3905.41 m;摩擦因数为0.25时,工作钻压增加到2.5 kN,下入深度由4370.00 m减小到4148.48 m。可见,在轴向压力作用下,连续管螺旋屈曲长度与摩擦因数成正比,下入深度与摩擦因数和工作钻压均成反比。所得结论可为连续管下入性研究及施工参数选择提供技术参考。Coiled tubing is prone to buckling deformation during operation in horizontal wells,which restricts its setting depth.In this paper,a study was conducted on the influence of axial load of coiled tubing on its setting depth in different hole sections.First,by analyzing the key parameters in the well track,a full angle plane of curved section was constructed.Second,based on the soft rod model and the constructed full angle plane,and considering the rigidity of coiled tubing,fluid friction,wall contact friction and additional contact friction after buckling,an axial load calculation model of coiled tubing was built.Finally,with the help of iterative method and combined with buckling state analysis,a case analysis was conducted on an well.The analysis results show that coiled tubing is more prone to spiral buckling in the vertical and slant sections.As the friction factor increases from 0.10 to 0.35,the spiral buckling length increases to 1189.19 m,and the setting depth decreases from 4370.00 m to 3905.41 m.When the friction factor is 0.25,the active weight on bit(WOB)increases to 2.5 kN,and the setting depth decreases from 4370.00 m to 4148.48 m.Obviously,under axial pressure,the spiral buckling length of coiledtubing is directly proportional to the friction factor,and the setting depth is inversely proportional to both the friction factor and the active WOB.The conclusions provide reference for research on the running ability and operation parameters of coiled tubing.

关 键 词：水平井 连续管下入性 轴向载荷 螺旋屈曲 下入深度 摩擦因数 

分 类 号：TE93[石油与天然气工程—石油机械设备]