Improvement of Productivity of Refining Process to Make High Purity Steel at No.3 Steelmaking Shop in Yawata Works, Nippon Steel

摘要

To respond to increasing user demand for high-purity steel production in recent years, we have improved the steelmaking process and, innovated a BQF-type hot metal pretreatment process (LD-ORP) and desulfurization process by a mechanically stirred ladle (KR). These days, the market for steel grades that have the essential degassing process, is increasing. We enhanced the degassing ability by constructing new REDA (revolutionary degassing activator, developed by Yawata Works) station for degassing by applying the operating skills in existence. These improvements of the refining process and the recent operation performance are presented.