Improvement of Contact Stress Distribution Between Work Roll and Backup Roll of a Hot Strip Mill

Abstract Contact state between work roll and backup roll has significant influnce on surface fatigue and strip steel shape. In this work, the contact behaviours between work roll and backup roll of a hot strip mill were investigated. The contact stress distributions along the axial and radial direction were calculated. The effect of uneven contact stress distribution on strip steel profile was analysed. The risk of roll fatigue caused by contact stress concentration was pointed out. In order to improve the contact stress distribution, a design method of the backup roll profile was proposed. Both finite element calculation and industrial test have been carried out and showed that the new profile was excellent in reducing the peaks of the contact stress, homogenizing backup roll wear and improving strip profile.