Calculation method and analysis of residual stress in the strip bending roller straightening process

Abstract The residual stresses in the roll straightening process of curved rolls of metal plates and strips are investigated by taking thin specification plates and strips as examples. Using the curvature integral and elastic‒plastic mechanics theory, the trajectory of the strip in the bending roll straightening process is analyzed, and a numerical analytical calculation method for the continuous straightening process of the strip in the bending roll is established. The results are verified by establishing an MARC finite element simulation. The effects of yield strength, plasticity rate and bending roll amount on the residual strain (stress) after straightening are investigated. In the straightening process, with increasing bending roll, the residual strain converges in the region Γ , the region Γ decreases with increasing yield strength, and the height of the wave increases with increasing yield strength, bending roll and plasticity rate. In addition, experiments were designed for verification. The results show that the logic of this calculation method is reasonable, the prediction error is within the scope of engineering application, and the method meets the intelligent needs of the bending roller straightening process.