Speedy switchover of operation from Tobata No. 1 to No. 4 blast furnace at Yawata Works*

Nippon Steel Yawata Works operates with only one blast furnace in service. BF No. 1 (inner volume : 4407 m3) was blown off on January 31, 1998 after operating for thirteen years. The third campaign of BF No. 4 (inner volume : 4250 m3) was started the following day and productivity reached 2.0 t/d.m3IV after fifteen days of operation. This paper describes the characteristics of the relining of No. 4 furnace. Also presented is the background of the speedy switchover of large blast furnace operation and the rapid increase in productivity without any reduction in output.