弯曲载荷下隔水管特殊螺纹接头参数与应力关系研究

Research on Relations of Stress and Parameter of Premium Threaded Connections on Riser Subjected to Bending Load

针对海洋环境中隔水管存在较大弯曲载荷的情况,采用有限元软件ANSYS对隔水管最易失效的特殊螺纹接头建立了三维接触有限元模型,得到了在弯曲载荷作用下螺纹接头的应力分布。结果表明:最大应力出现在接头本体拉伸侧的第1圈或最后1圈螺纹的根部;接头本体拉伸侧与压缩侧的螺纹根部应力分别与环向角近似成1/2个正弦波函数关系。在此基础上进一步分析了壁厚、螺高、螺距、螺纹圈数和锥度等参数对螺纹处最大等效应力的影响,为隔水管特殊螺纹接头的设计与优化提供了理论依据。

According to the situation of riser subjected to large bending load a＇ the ocean circum- stance,the 3D contact finite element analysis model for premium threaded connections which is the most likely to become failure is established with the finite element software of ANSYS. The characteristic of Stress distribution on threaded connections under bending loads is obtained. The result reveals that the maximum stress exists on the first or the last round of thread root in the tensile side of connections;the relations of thread root stress distribution in 1he tensile side and compressive side of the connections with circular angle is represented as approximately half sine respectively. On this basis,detailed analysis is given on the effect of the threaded parameter such as wall thickness, depth of thread, thread pitch, number of thread teeth and taper on the maximum equivalent stress. Thus it can be taken as references in design and optimization of premium threa- ded connections.