To formulate an optimum condition for minimizing crop loss in slabbing and blooming, the crop calculation program has been constructed on the basis of the model tests for plasticine and hot steel. In slabbing, it is shown that the influence of each factor of ingot size, ingot end profile, and rolling schedule upon crop loss formation changes in different ways according to the choice of their combination by use of the crop calculation program. The optimum rolling condition also depends upon the production mix of slabs.
The crop calculation program is applicable to minimize crop loss in blooming, as well. It is shown that most of crop loss is formed in the earlier stage of rolling schedule before the groove rolling pass, and that the influence of reduction at each pass on the change of crop loss decreases in proportion to the increase of pass number.
