Abstract: This is Paper One in a series of articles on the three-dimensional FEM analysis of stress-intensity factor in petroleum drill pipe joint with surface crack,in which is given a basic calculation fqrmula fob a solution to the surface crack by three-dimensional FEM displacement methods.Quite a few calculation examples show that the solution used in this paper can fairly accurately present the regularity of change in the stress-intensity factor along the leading edge.And Moreover,here is presented a simplified model for petroleum drill pipe joint screw-thread connection.The regular distribution in the load along the screw insection is reasonably stimulated.

摘要： 给出了三维有限元位移法求解表而裂纹的纂本计算公式通过若干算例表明,本文所用的求解方法能较精确地给出应力强度因子沿裂纹前缘的变化规律,提出了石油钻杆接头螺纹连接的简化模型、合理地模拟了载重荷沿螺纹齿的分布规律.

关键词: 石油钻杆, 螺纹接头, 表面裂纹, 应力强度因子, 三维有限元