Advanced Technology for the Unsteady Stage Slab Quality at Kashima Steelmaking Plant.

摘要

In recent years, quality requirements for the continuous casting slabs have become stricter. On the other hand, various requirement to steel from customers made it difficult to increase the sequential number of the continuous casting. As the result, unsteady stage slab has been increased. It is well known that the quality of unsteady stage slabs was worse than that of slabs produced during steady state casting. Therefore unsteady stage slabs had not been applicable to strict specification due to its inferior inner quality such as inclusion. To solve the problems, the Constant Withdrawal Method at the final stage of casting, the High Acceleration Method at the initial stage of casting and a new shrouding system have been developed at S.M.I./Kashima Steel Works. Consequently, the quality of unsteady stage slabs was remarkably improved.