Solid metallic charge material such as scrap, pig or sponge iron is melted down in a metallurgical furnace e.g. a basic-oxygen converter using a fuel-oxygen burner by first pre-heating the charge material to white heat, i.e. above 1000 DEG C. but below its M.P. e.g. to 1200 DEG C., with a broad short flame which impinges on the whole charge surface, and then melting down with a narrow long flame which impinges on the central charge portion only, the burner distances from the charge surface being such during each period, e.g. 250 mm. in the pre-heating period and a constant 400 mm. in the melting down period, that the hottest zone of the flame touches the charge surface. A broad short flame may again be produced after the melting down period to melt remaining outermost solid portions of the charge. The final bath temperature may be 1610 DEG C. The above process may be carried out in the converter while stationary and upright; after melting the converter may be rotated in the inclined position.
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