How to prevent roll hazards to improve operational efficiency?

The operating conditions of rolls in rolling mill components are the most messy. Rolls in the production and use of the preparatory process before the occurrence of residual stress and thermal stress. Use and further by a variety of cyclic stress effects, including bending, alteration, shear, contact stress and thermal stress. The distribution of these stresses along the roll body is uneven, constantly changing, due not only to planning factors, but also in the use of roll wear, temperature and roll shape of the constant changes. In addition, the rolling conditions often present anomalous conditions. Rolls in the use of improper cooling, but also by the harm of thermal stress. So the roll in addition to wear and tear, but also often show cracks, cracking, shedding, indentation and other kinds of partial damage and appearance damage. A good roll, its strength, wear resistance and other performance indicators should be a better match. In this way, not only in the normal rolling conditions, durable, but also in the presentation of some abnormal rolling conditions when the damage is small.

So in the production of rollers to strictly control the metallurgical quality of the rolls or supplemented by external measures to enhance the bearing capacity of the rolls. Reasonable roll shape, hole type, deformation criteria and rolling conditions can also reduce the operating load of the roll, to prevent some of the peak stress, extending the life of the roll. Occurrence of causes and rolls of their own residual stress, rolling mechanical stress and roll thermal stress, especially when the roll body of the appearance and the core of the temperature difference is more likely to occur. This temperature difference can be caused by poor roll cooling, cooling suspension or overheating of the roll exterior at the beginning of a new rolling cycle. Rolls of this appearance and the core of the infinite temperature difference between the larger thermal stresses, when the larger thermal stresses, mechanical stresses and rolls of the residual stress beyond the core strength of the rolls lead to broken rolls.
Cold welding repair method: cold welder roll is the use of electric spark high frequency discharge principle of metal appearance of heatless welding, so in the process of repairing roll blisters, scratches and other shortcomings in the process of no deformation, no annealing, no biting edges and residual stresses, do not change the state of the metal arrangement. Correction of high precision, coating thickness from a few microns to a few millimeters, can be presented on the metal workpiece wear, scratches, pinholes, cracks, defects, deformation, hardness decline, trachoma, damage and other shortcomings of the stacking, sealing holes, make up for the corrective function, just grinding, polishing, but also can be carried out in the car, milling, planing, grinding and other types of machining, as well as plating and other post-processing.

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