管螺纹接头在轴向拉力作用下.扣牙力分布曲线呈两头高、中间低的抛物线状.这种极不均匀的扣牙力分布是制约管螺纹承载能力的根本原因.本文定性描述了扣牙力分布曲线的成因.并用解析法定量求出管螺纹旋合段内的各个扣牙力.实验证明.这种方法的计算精度可较好地满足工程计算的需要. Under the action of axial tensile force, the pipe thread joint has a parabolic curve with two heads and a low middle, which is the root cause that restricts the load carrying capacity of pipe threads. The causes of dental force distribution curve are analyzed, and the deduction of each buckling force in pipe screwing segment is obtained by analytical method.Experiments show that the calculation precision of this method can meet the needs of engineering calculation well.