PURPOSE: To reduce fuel expense of a heating furnace, by operating the heating furnace by a heating pattern for a hot piece material, whose fuel consumption is small, by raising a temperature of a slab of a hot piece material and a slab of a cold piece material up to a desired temperature by heating once and twice, respectively.
CONSTITUTION: To a heating furnace 1 operated by a heating pattern for a hot piece material, a slab of a hot piece material carried on a charging table 2 from a charging conveyor 4 is charged by a pusher 3, is heated to about 1,200°C, and after that, is extracted onto an extracting table 5 by an extracting device 6, immediately is carried to a rolling mill group 7, and is rolled. In case when the slab is a cold piece material, the slab is heated to about 1,000°C by the first heating, and after that, is extracted, passes through a turntable 8, a recharging table 10 and a turntable 9 from the extracting table 5, is charged into the heating furnace 1 by the pusher 3 from the charging table 2, is subjected to reheating, is extracted at about 1,200°C to the extracting table 5 by the extracting device 6, and after that, is carried to the rolling mill group.
UCHIDA SHIGETAKA
SHIRAISHI KAORU
UENO YASUSHI
TERAMOTO TOYOKAZU
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