钢管折弯畸变原因分析

Analysis on the causes of distortion in the process of pipe bending

钢管折弯过程是通过外力使钢管发生塑性变形的过程。在使用弯管机对钢管进行折弯的过程中,在靠模与转模作用力形成的力偶作用下,钢管发生塑性变形。当靠模与转模之间的距离不同时,钢管所受应力状态也会有所不同,当该距离满足某一数值时,钢管折弯截面上的剪应力将处于主导地位,钢管容易产生畸变。本文通过对钢管折弯过程中各向应力状态和塑性变形进行分析,推导出畸变时靠模与转模之间的距离及其与钢管直径之间的数学关系,以期对管路折弯工艺及设备提供指导。

The bending process of steel pipe is the process of plastic deformation of steel pipe by external force. In the process of bending the steel pipe by bending machine, the steel pipe has plastic deformation under the action of the force couple formed by the force of the profiling and the rotary mould. When the distance between the die and the die is different, the stress state of the steel pipe will be different. When the distance meets a certain value, the shear stress on the bending section of the steel pipe will be in the dominant position, and the steel pipe will be distorted easily. In this paper, through the analysis of the stress state and plastic deformation in the process of steel pipe bending, the distance between the die and the die and the mathematical relation with the diameter of the steel pipe are deduced, so as to provide guidance for the pipe bending process and the equipment.