The pressure generated during the bending deformation combined with the residual stress existing in the strip, often causes the strip to deviate from the cold-formed steel equipment. To solve this problem, a straightening mechanism should be used at the end of the steel roll forming machine. The basic principle of the straightening mechanism is that for profiles with defects such as side bending and warping, apply sufficient pressure in the opposite direction through the straightening mechanism to cause irreversible deformation.
If the amount of deformation in the opposite direction is correct, the profile can be completely straightened after springback. If the formed profile is twisted in one direction, the straightening mechanism sequentially rotates the profile in the opposite direction, resulting in a fixed plastic deformation. If the angle of rotation is correct, the profile will no longer twist after springback.
Straightening of bends or twists, usually between forming rolls and cutting dies. If the rolls cannot effectively support the profile, then the entire profile section needs to be supported as it enters one side of the straightening mechanism. When straightening an asymmetrical profile, torsional deformation may occur while straightening. At this time, it is necessary to perform bending and torsional straightening in the opposite direction of the profile deformation.