TOKYO — JFE Steel Corporation today blew in the newly revamped No.5 blast furnace (BF) at the West Japan Works (Fukuyama) for its third campaign.

The 21-billion yen revamp was carried out between February 1 and March 30 using the large-block ring construction method, JFE Steel's proprietary ultra-short-term revamping technology. The company has successfully used this method to shorten the revamping periods of BFs at its East Japan Works (Chiba) and West Japan Works (Kurashiki), but the latest revamp was the first time this method was employed at the Fukuyama district. It took only 58 days, a world record for a large (5,000m³ class) BF, breaking the previous record of 62 days for the revamp of the No.6 BF at the Chiba district in 1998.

The Fukuyama No.5 BF's inner volume has increased from 4,664m³ to 5,500m³, and there are now four tapping holes instead of three. The furnace currently operates with four hot stoves as a previously out-of-service stove was renovated.

A new bell-less top has replaced a four-bell device in the furnace top raw material charging equipment, further improving raw material distribution control and enabling use of greater volumes of less costly raw materials, which results in lower production costs.

In addition, highly corrosion resistant refractories were used and the shaft cooling system was reinforced among other measures to further prolong the operating life of the furnace.

Reference

1. Fukuyama No.5 BF's operation periods

2. JFE Steel BFs revamped by the large-block ring construction method

BF/works	Blow-in date	Revamp period	Inner volume
No.5 BF at West Japan Works (Fukuyama)	March 2005	58 days	5,500 m3
No.6 BF at East Japan Works (Chiba)	May 1998	62 days	5,153 m3
No.4 BF at West Japan Works (Kurashiki)	Jan. 2002	70 days	5,005 m3
No.2 BF at West Japan Works (Kurashiki)	Nov. 2003	75 days	4,100 m3

JFE Steel's Fukuyama No.5 BF (after revamping)