English to Russian Tech/Engineering Metallurgy / Casting Дуговая металлургиеская печь

Above the heated metal and slag is an area of space referred to as “freeboard”, which is surrounded horizontally by the refractory.
Above the freeboard, metallurgical furnaces typically have some form of roof.
The section shown is from the “freeboard” space of the furnace. The freeboard space is above the “slag line” in the furnace 10, above which there is typically no molten or solid metal or slag in the furnace during operation.

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