numerical and experimental investigations on strip deformation in cage roll forming process for pipes with small thickness/diameter ratio

cage roll forming is one of the new methods of cold roll forming process which is widely used for producing erw pipes. in addition to less production cost and time, using cage roll forming provides smooth deformation on the strip. few studies can be found about cage roll forming because of its complexity, and the available knowledge is more experience-based and not science-based. in this paper, deformation of pipes with small thickness/diameter ratio is investigated by 3d finite element simulation in marc-mentat software. edge buckling defect in roll forming of pipes with small thickness/diameter ratio is very important. due to direct effect of longitudinal strain on the edge buckling phenomenon, longitudinal strains at the edge and center line of the deformed strip are investigated and the high risk stands are introduced. deformation flower pattern and curvature of the deformed strip are predicted using the simulation results and the effects of each cage forming stage on the deformed strip profile are specified. in order to verify the simulation results, circumferential length, opening distance of the two edges and forming power in different forming stages are obtained from the simulations and are compared that of the experimental data which were measured from the production line. a good agreement between the experimental and simulated results is observed.