The working conditions of the roller in the roller parts are the most complex. The residual stress and thermal stress will be produced in the preparation process of roll before and after use. When used, it is further affected by various kinds of cyclic stress, including bending, torsion, shear force, contact stress and thermal stress. The distribution of these forces along the roll body is uneven and changing, and the reasons are not only the design factors, but also the wear, temperature and roll shape of the rollers in use.
In addition, roll conditions often appear abnormal situation. After cooling, the roller will be damaged by thermal stress. Therefore, in addition to wear and tear, but also often crack, fracture, spalling, indentation and other local damage and surface damage. A good roll, its strength, wear resistance and other performance indicators should have a better match.