管螺纹接头齿根表面裂纹的数值分析

The Numerical Analysis for the Surface Crack at the Thread Root of a Screwed-Pipe Joint

本文采用一种混合的数值方法对管螺纹接头齿根中存在半椭园型表面裂纹的断裂强度作了三维数值分析，采用虚拟接触载荷法模拟啮合螺纹齿间的接触现象，确定载荷沿螺纹齿的分布规律，并求解出裂纹区的变形位移场。最后采用位移法。计算出裂纹体的应力强度因子。

A mixed numerical method is proposed in this paper to make the three-dimensional numeri-cal analysis about the fracture intensity of the Screwed-pipe joint,with a semi-elliptical surfacecrack existing at its thread root.The virtual contact loading method is employed to simulate thecontact phenomenon between the engaged threads,determine the load distribution along thethreads and find out the displacements near the craek front.Then the stress-intensity factors ofthe cracked joint can be calculated by the displacement method.