摘要
特殊螺纹接头在井下服役期间受到交变载荷作用,导致接头密封面处发生微滑,影响接头的密封性能。为研究特殊螺纹接头密封面处的微滑接触行为,基于弹性杆振动微分方程,建立了特殊螺纹接头微滑模型,分析了接头密封面的黏着-滑移临界区域及载荷-位移的迟滞特性;利用数值仿真软件建立了接头摩擦接触有限元模型,考察不同内压载荷、位移幅值和摩擦因数的影响下,接头密封面接触压力、相对滑移距离和剪切摩擦力的变化规律,得到了接头密封面处黏着-滑移状态的临界转化范围。研究结果表明:接头的摩擦接触有限元模型可模拟井下实际工况下接头密封面的微滑接触行为;随着内压载荷的增加,相对滑移距离减小、剪切摩擦力和黏着长度增加;随着位移幅值的增加,相对滑移距离增加,黏着长度减小;在内压载荷60~70 MPa之间,位移幅值0.02~0.025 mm之间,分别在密封面处发生黏着-滑移状态的临界转化;随着摩擦因数的增加,密封面相对滑移距离减小,剪切摩擦力和黏着长度增加。研究结果可为动载作用下特殊螺纹接头密封性研究提供参考。
The premium connection is subjected to the alternating load during downhole,resulting in a micro-slip at the sealing surface of premium connection,which affects the sealing performance.In order to study the micro-slip contact behavior at the sealing surface,based on the elastic rod vibration differential equation,a micro-slip model of premium connection was established,and the critical area of micro-slip and the hysteresis characteristics of load-displacement of the sealing surface of premium connection were analyzed.The finite element model of friction contact of premium connection was established by numerical simulation software,and the change law of contact pressure,relative slip distance and shear friction of the sealing surface of premium connection under the influence of different internal pressure loads,displacement amplitude and friction coefficient were investigated,and the critical conversion range of the micro-slip state at the sealing surface of premium connection was obtained.The results show that the frictional contact finite element model can simulate the micro-slip contact behavior of the sealing surface under the actual working conditions of the downhole.With the increase of internal pressure load,the relative slip distance decreases,and the shear friction and adhesive length increase.With the increase of displacement amplitude,the relative slip distance increases and the adhesive length decreases.When the internal pressure load is between 60 MPa and 70 MPa and the displacement amplitude is between 0.02 mm and 0.025 mm,the critical transition of micro-slip state occurs at the sealing surface respectively.With the increase of the friction coefficient,the relative slip distance of the sealing surface decreases,and the shear friction and adhesion length increase.The research results can provide a reference for the study of the sealing performance of premium connection under dynamic load.
作者
曹银萍
刘渝
于洋
李贞贞
窦益华
CAO Yinping;LIU Yu;YU Yang;LI Zhenzhen;DOU Yihua(Mechanical Engineering College,Xi’an Shiyou University,Xi’an Shaanxi 710065,China;Aeronautics College,Northwestern Polytechnical University,Xi’an Shaanxi 710072,China)
出处
《润滑与密封》
CAS
CSCD
北大核心
2024年第4期18-26,共9页
Lubrication Engineering
基金
国家自然科学基金项目(52274006)
陕西省自然科学基金项目(2023-JC-YB-337)。
关键词
特殊螺纹接头
密封面
微滑接触
密封性能
滑移状态
premium connection
sealing surface
micro-slip contact
sealing performance
micro-slipstate
