When Kokura No. 2 B.F. was blown out on 25th, Sept., 1974, the furnace was quenched with water and the investigation in the blast furnace was carried out concerning the following items:
(1) The distribution of burden materials, patterns of melting zone and shapes of the raceway in the furnace.
(2) The change of some properties of coke and sinter in the furnace.
(3) The relationship between operating conditions and some phenomena in the furnace.
