This device has a pre bending function at the end of the sheet metal, which can load the metal sheet metal in one go without turning the head to complete the pre bending of the sheet metal end and the rolling forming of the workpiece. The working roller on the machine is the main driving roller, and the lifting and lowering of the lower roller and the two side rollers are both hydraulically driven. The lifting displacement is controlled by a computer, automatically leveled, and displayed on the screen. The tilting and resetting of the flipping bearing body are hydraulically driven. The tail of the upper roller is equipped with a balancing mechanism, which can facilitate the unloading of the rolled workpiece and cylinder. The machine is equipped with a mobile independent operating platform that can be moved and operated at any time. The machine is equipped with a safety interlock device, which has high technical level, full functions, high accuracy, and easy operation. It is the most ideal preferred model for rolling circular, curved, and conical workpieces in industries such as energy, transportation, petroleum, chemical, boiler, shipbuilding, hydropower, and metal structures.