A Study of Cold Roll Forming Technology and Peak Strain Behavior of Asymmetric Corrugated Channels

Abstract

The peak strain (PS) of sheet metal highly affects the process design and the quality of roll formed product. Different from the traditional roll forming technology (RFT) that all the cross section contours of the product are rolled simultaneously, a symmetric RFT is developed with respect to the corrugated channels under the study to avoid defects like tearing, twist and redundant deformations. The behaviors of their peak strains are subsequently simulated with Finite Element (FE), and the effects of three factors of the rolling speed, friction coefficient and the bending angle of roll are analyzed, respectively. Finally, both the rationality of RFT and the accuracy of final rolled product are verified by experiments. Results show that for two roll forming channels at the same time, even under the equal bending angles and the pressures of rolls, their maximum peak strains are also distinguished for their different channel widths. The maximum PS of the narrow channel is significantly larger than that of the wide, and the closer to the middle channel, the greater the PS of the narrow channel, which is on the right of bending angle of the trough. Moreover, the maximum PS is dominant by the friction coefficient and bending angle of the first forming pass. This can provide a reference in the design of RFT and improving the quality of the final rolled corrugated channels.