Recent Trends in Iron and Steel Making in Japan

Abstract

Iron making TABLE I shows the results of the blast furnaces in Japan in 1958. The total national output of pig iron in 1957 was 6,500,000 tons. Twenty-seven of the thirty-nine blast furnaces were in operation, and the production per blast furnace was as follows: 1953 1954 1955 1956 1957 Production per blast furnace (t/d) 597 571 654 682 683 Whenever new blast furnaces are erected or blast fur- naces are relined, the tendency is to enlarge the inner volume of the furnace. Tobata No. I Blast Furn- ace of Yawata Works, which is expected to be blown-in by end of 1959 will be I,500t/d.Effort is made chiefly towards enlarging furnace capacity by decreasing the thickness of the furnace walls. For example, the inner volume of Higashida No. 4 Blast Furnace has been raised to 537m3 from 474m3 by reducing the walls of the bosh from 650 mm to 425 mm, and those of the shaft from 710 min to 575 nim. The use of carbon blocks has also gradually increased. At the Kukioka No. I Blast Furnace carbon block is used even for the bosh. Almost all blast furnaces in Japan have started using carbon blocks, thereby preventing damage to the bottom of the furnaces.