井斜角与摩擦对连续油管正弦屈曲的影响研究  

Study on influence of inclination angle and friction on sinusoidal buckling of coiled tubing

作　　者：龚银春[1] 艾志久[1] 付必伟[1] 汤海平[1] 

机构地区：[1]西南石油大学机电工程学院,四川成都610500

出　　处：《中国安全生产科学技术》2016年第10期50-55,共6页Journal of Safety Science and Technology

基　　金：国家自然科学基金项目(51074132)

摘　　要：为了避免连续油管井下屈曲行为的产生,进而导致井下作业事故,开展了井下管柱正弦屈曲行为的研究。根据最小势能原理建立了一个复杂的井下管柱正弦屈曲模型。在考虑摩擦的情况下,构建了斜井中的管柱屈曲微分方程组。通过对屈曲微分方程组进行无量纲化处理,使方程组能独立于井下泥浆、井眼尺寸和管柱形式而存在。最后,采用虚功原理研究了摩擦与井斜角对正弦屈曲临界载荷的影响。研究结果显示,正弦屈曲临界载荷将随着摩擦系数的增加而增加。此外,随着井斜角的增加,正弦屈曲临界载荷也将不断增加。该研究结果可为连续油管预防井下作业事故的发生提供理论性指导。In order to avoid the downhole buckling of coiled tubing,which may lead to downhole operation accident,the study on sinusoidal buckling of downhole string was carried out. A complicated sinusoidal buckling model of downhole string was established based on the principle of minimum potential energy. The differential equations of string buckling in inclined shaft were constructed considering the friction and treated with dimensionless method to enable the equations existing with independence of downhole mud,wellbore size and string type. Finally,the principle of virtual work was applied to study the influence of friction and inclination angle on critical load of sinusoidal buckling. The results showed that the critical load of sinusoidal buckling increases with the increase of friction coefficient. In addition,with the increase of inclination angle,the critical load of sinusoidal buckling also presents an upward trend. It can provide theoretical guidance to the prevention of downhole operation accidents for coiled tubing.

关 键 词：摩擦 井斜角 连续油管 正弦屈曲 

分 类 号：X937[环境科学与工程—安全科学]