Abstract
It is generally considered by engineers that strong refining in a high frequency induction furnace is difficult, having a thin lining and some faults. But the author has being engaged in the industrial manufacturing of low phosphorus pig iron since the end of Second World War (July 1947) in Akita Steel Mfg. Co., Ltd. in performing as strong a refining by using a ½ ton furnace as by the closed typed Héroult Arc Furnace, which had the lining as shown below—namely, the acid lower lining, and the basic upper slag line. The mixing ratio of the acid lining is : Quartz 4 mesh∼8 mesh 43kg (21%) Quartz 8 mesh∼45 mesh 50kg (25%) Quartz 45 mesh∼65 mesh 36kg (27%) Chamotte brick waste—65 mesh 65kg (32%) "Kibusi" clay powder 10kg (5%) The basic lining consisted of 20% Magnesia clinker and 80% Dunite clinker (forsterite system refractory material), of which powder and grain were properly mixed in fifty-fifty. This furnace life is 20 times in average. The above—is very useful as the author believes the development of the high frequency induction furnace and economic future of pig iron for nodular cast iron.
