In the No. 2 Steel making plant at Kashima Steel Works, CC-DC (Continuous Casting Direct Charge) process has been adopted to realize the synchronized operation between a caster (3CC) and a hot strip mill. In order to take advantage of this process, the BOF (Basic Oxygen Furnace) operation has been required to hit exact end-point carbon contents and metal bath temperatures, and to shorten the refining time. In addition, steel quality depends largely on the end-point hitting ratio. To meet the requirements, we have developed a new endpoint control system of BOF since the renewal of a process computer in 1992.
After the adoption of the new system, the direct tapping ratio is about 70%, which results in the reduction of operational cost and the improvement of productivity.
