套管接头泄漏和滑脱机理探讨

DISCUSSION OF MECHANISM OF THE LEAKAGE AND JUMPED-OUT ABOUT THE THREADS OF CASING CONNECTOR

在深井、超深井、大位移井和水平井中 ,套管接头泄漏和滑脱特性是国内外油气井管柱力学研究的永恒主题。通过调研国内外大量文献资料 ,探讨了套管螺纹泄漏机理、螺纹滑脱机理研究的思路和研究方向———除实物试验外 ,有限元法是可行的简便方法之一。运用有限元法 ,对套管偏梯形螺纹接头和圆形螺纹接头进行了研究 ,得出了偏梯形螺纹接头在牙侧角为 3°、5°和 10°时 ,滑脱载荷随加载过程的变化曲线 ;圆形螺纹接头在锥度为 1/14、1/16和 1/17时 ,滑脱载荷随加载过程的变化曲线。其研究结果 ,在深井、超深井和复杂井套管柱设计中 ,为套管接头螺纹的选择提供了理论数据。

Under the deep well, extra- deep well, extend well and horizontal well, the properties of the leakage and jumped - out of the casing connector is the topic that is studied forever at home and abroad in the research of the oil-gas pipeline mechanics. Based on the study of many literatures, the develop object of the premium connections was presented in the paper, the mechanism of the leakage and jumped-out of the threads of casing connection was discussed in detail. The stresses of the connection of the buttress and round threads were analyzed with finite element method ( FEM), the curves of the jumped-out loads varied with the time was obtained when the flank angles of the buttress are 3°, 5° and 10° degreed, respectively. With the three tapers 1/14, 1/16 and 1/17, for the round casing connector, the curves that the jump-out loads varied with the loading process were obtained. It provides the theoretical supports for the selection of the casing connectors in the extra-deep well and complex well.