Principles to be followed in the process of cold roll forming machine

The basic principle of the cold forming process is: the strip is bent straight in the longitudinal direction. However, the pressure generated during the bending deformation is combined with the residual stress in the strip, and the strip often deviates from the cold bending equipment. In order to describe the degree of deviation of the strip from the next forming roll, the commonly used words are: side bending-horizontal bending, warping-vertical bending, twisting-spiral. In order to solve this problem, a straightening mechanism should be used at the end of the roll forming machine.

The basic principle of the straightening mechanism is that for profiles with defects such as side bending and warping, the straightening mechanism can produce permanent deformation by applying sufficient pressure in the opposite direction. If the amount of deformation in the opposite direction is appropriate, the contour can be completely straightened after rebound. If the profile is twisted and deformed in a specific direction, the straightening mechanism will rotate the profile in the opposite direction to produce permanent plastic deformation. If the rotation angle is right, the contour will no longer be distorted after the rebound.

The straightening of the bending or twisting is usually carried out between the subsequent forming roll and the cutting die. If the subsequent roll cannot effectively support the contour, the entire contour part needs to be supported when entering one side of the straightening mechanism. Straightening an asymmetric profile means that torsional deformation may occur when straightening. At this time, it is necessary to simultaneously perform bending and torsion straightening in the opposite direction of the contour deformation. During the straightening process, the profile will move left and right, which requires a relatively loose gap between the straightening mechanism and the profile. There may be a certain gap between the straightening mechanism and the surface of the profile.