The automatic feeding device lifts the steel pipe to the conveying roller table, and the conveying adopts a rotary feeding mode, so that the steel pipe rotates at a uniform speed into the heating section and the heat preservation section for stabilizing heat treatment; Then enter a 360-degree spraying device for uniform cooling; After the steel pipe is cooled, it is rotated out by the output roller table at a uniform speed; After cold cutting, the steel pipe is quickly separated into the blanking area. The automatic blanking device is triggered to automatically lift the steel pipe onto the blanking platform. During the whole process steel pipe will not produce any scratches.