GEN-CONVERTER PLANT AT KUKIOKA, YAWATA WORKS
Tatsuhei Uchiyama, Shigeru Maehara
Some experiments were carried out in 1955-56 with a 5-ton experimental oxygen converter to see whether the pure oxgen converter could be used practically in Japan. As the result it was ascertained that this method was available even to refine the high-P, high Si molten pig in Japan and the resultant products were of superior quality.
The construction of a new pure-oxygen converter plant started in Nov., 1056. It began operationon Sept. 17, the next year. The new plant, that installed two 50-ton converters, tapping 30 charges a day in average, had already produced by the end of April, 1958, 190, 000 tons of ingots for the Tobata strip mill.
The characteristics of equipments in this plant are the well-balanced layout for making the flow of operation easier and smoother, transportation of ingots and slag pans by special automobiles, the waste-gas heat boilers and dust catchers working out most completely than any other in the World, and the special pouring method by which one charge of steel is able to be poured into the ingot-cases (8 ton ingot×6) on a wagon through one fountain, etc. The mixer iron available has the average analysis of C 4.5%, Si 0.65%, Mn 0.95%, P 0.20%, S 0.03%. The product has average compositions of P 0.020%, N<sub>2</sub> 0.002% and S 0.017%. The mechanical properties of the cold-reduced strip sheets of 0.6-1.2mm thikness have shown better elongation and Erichsen values in comparison with those of the ones produced by open hearth furnaces.