The principle of  induction pipe bending machine :we can get the requiring bending pipe by mediate-frequency power supply heating the pipe in the process of  pushing pipe forward at a constant speed. First , loading the pipe, then through the leading screw transmission device make rocker arm along a rotary device to adjust the bending radius. After heating the pipe at a certain temperature by medium-frequency coil, then the pipe is bended. In the bending ,  the pipe is  pushed forward by  oil cylinder and clamping by  four waist wheel of platform. Cooling the pipe at the same time, then the required bending pipe can be obtained.
     To prevent the pipe as a oval after heating,   pre deformation pipe is necessary .