特殊螺纹油套管接头完整性评估计算分析

针对特殊螺纹油套管接头的主要结构加工参数进行了接头连接和密封性能的评估计算公式推导,并设计完成了一套特殊螺纹接头油套管完整性评估软件。首先,通过对油套管接头失效形式及机理分析,推导出各失效形式对应的临界载荷计算公式;然后,通过对单个螺纹牙的弹性变形分析,建立整体油套管螺纹接头的力学分析模型,结合变形协调方程推导得到接头螺纹牙承载分布求解公式;最后,通过对比临界载荷与实际承载以及密封面总接触压力与管内气体压力完成接头完整性评估。评估结果表明:在相同载荷作用下,TM型接头套管最易发生剪切破坏失效;密封面总接触压力大于管内压力,密封性能良好。

Integrity Evaluation Analysis of Casing Premium Connection

Based on the main structural processing parameters of the casing premium connection,the calculation formulas for the connection and sealing performance were derived.The integrity evaluation software for the casing premium connection was designed and completed.First,the critical load formulas corresponding to each failure form were derived by analyzing the failure form and mechanism of the casing connection.Then,by analyzing the elastic deformation of a single thread tooth,the mechanical analysis model of the casing connection was established,and the solution formula for loading distribution of the connection threads was derived in combination with the deformation coordination equation.Finally,the integrity of the connection was evaluated by comparing the critical load with the actual load and the total contact pressure on the sealing surface with the gas pressure in the pipe.The evaluation results show that under the same load,the TM connection casing was most prone to shear failure;the total contact stress of the sealing surface was greater than the pressure inside the pipe,and the sealing performance was good.