In order to improve the service life of work rolls, corresponding measures can be taken from the following aspects. The development of new roll material and improvement of manufacturing process are effective measures to prolong the life of roll, and the way to add new alloy elements is sought to improve the crack resistance and wear resistance of roll. The rolls with cracks should be replaced and grinded in time. The amount of grinding depends on the degree of wear, so as to prevent the cracks from penetrating and expanding. In order to reduce or eliminate the internal stress, the work roll should be annealed once in a service cycle, or the grinded roll should be immersed in the oil with a certain temperature for preservation. For the work roll with slag drop, casting shrinkage hole or shrinkage porosity, the feasible repair method is studied to make it reusable. For the work rolls which have lost surface hardening layer due to repeated grinding, re-quenching treatment is carried out and continue to be used to improve the surface hardness and prolong the service life of the rolls. For the work roll whose neck is twisted and broken, the possibility of turning the head is considered, and the transmission end is changed and reused. From the technological point of view, the supply and discharge time, position and flow rate of cooling water are considered. If cooling water is supplied to the pass clearance, the supply of cooling water is stopped during the rolling process. Secondly, reasonable matching of rolls makes the lower work roll slightly larger than the upper work roll neck, and reasonable grinding and configuration of roll profile considering rolling pressure and thermal expansion, so that the concavity value of the upper work roll is slightly larger than that of the lower work roll. Thirdly, according to the high temperature characteristics of the rolled material, reasonable distribution of reduction, prevent overpressure, non-uniform reduction and long-term skidding can not bite into the operation methods.
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