1
Faculty of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran
2
Department of Mechanical Engineering, Faculty of Engineering, University of Science and Culture, Tehran, Iran
3
Department of Mechanical Engineering, Arak University, Arak, Iran
4
Department of Mechanical Engineering, Technical and Vocational University(TVU), Tehran, Iran
10.48311/mme.2026.118307.82909
Abstract
This paper, relying on a developed flower pattern and a geometric model based on the involute curve, investigates the strain stress behavior, the gradual load transfer and the possibility of geometric and mechanical defects in the two processes. The aim is to present an analytical-numerical method for accurately comparing the forming steps, determining the position and angle of the rollers and analyzing the effect of the proposed arrangement on improving the mechanical response of the sheet. The working method includes developing the developed flower pattern, extracting the involute equations, determining the configuration of the five-station rollers by numerical solution in MATLAB and analyzing the stress-strain analysis with a 3D Abaqus model. By comparing the cross section of sheet obtained from the method and that of another reference, validation of the method was confirmed. The equivalent strain study at the first station indicated that the conventional roll forming process produces 15% more strain in the edge area than the flexible process. Also, the longitudinal strain in critical areas such as the edge is 79% lower in the flexible roll forming process than in the conventional roll forming process. The average values of stress obtained show that the flexible roll forming process produces a 27% reduction in stress compared to the conventional one. By gradual control of curvature and more uniform distribution of loading, in the flexible roll forming process not only reduces critical strains, but also effectively reduces the possibility of defects such as edge cracking, local thinning and cross-sectional distortion.
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Jabaseh,Z. , Moslemi Naeini,H. , Mazdak,S. and Dadgar Asl,Y. (2026). Comparison of conventional roll forming process and flexible pipe roll forming process. Modares Mechanical Engineering, 26(3), 157-168. doi: 10.48311/mme.2026.118307.82909
MLA
Jabaseh,Z. , , Moslemi Naeini,H. , , Mazdak,S. , and Dadgar Asl,Y. . "Comparison of conventional roll forming process and flexible pipe roll forming process", Modares Mechanical Engineering, 26, 3, 2026, 157-168. doi: 10.48311/mme.2026.118307.82909
HARVARD
Jabaseh Z., Moslemi Naeini H., Mazdak S., Dadgar Asl Y. (2026). 'Comparison of conventional roll forming process and flexible pipe roll forming process', Modares Mechanical Engineering, 26(3), pp. 157-168. doi: 10.48311/mme.2026.118307.82909
CHICAGO
Z. Jabaseh, H. Moslemi Naeini, S. Mazdak and Y. Dadgar Asl, "Comparison of conventional roll forming process and flexible pipe roll forming process," Modares Mechanical Engineering, 26 3 (2026): 157-168, doi: 10.48311/mme.2026.118307.82909
VANCOUVER
Jabaseh Z., Moslemi Naeini H., Mazdak S., Dadgar Asl Y. Comparison of conventional roll forming process and flexible pipe roll forming process. Modares Mechanical Engineering, 2026; 26(3): 157-168. doi: 10.48311/mme.2026.118307.82909
