CONTINUOUS FURNACE WITH UPPER AND LOWER HEATING OF METAL Russian patent published in 1998 - IPC

FIELD: metallurgy; may be used in heating of metal ingots, in particular, slabs. SUBSTANCE: furnace includes arch, bottom and side walls with offtake located from atop on the side of furnace inlet end and connected with recuperator, movable beams for displacing metal along the furnace and burners located above and under the beams. Additional offtakes are made over height of side walls at furnace inlet end under the beams and connected with respective recuperators. Located opposite to each recuperator is bent wall with longitudinal and transverse parts adjacent to side wall and directed with its longitudinal part towards furnace inlet end. Width of additional offtakes equals 0.2-0.6 width of respective recuperator. Upper end face of bent wall is located below the level of upper surface of beams by a value equalling 0.01-0.05 width of respective recuperator. Length of transverse part of bent wall equals 0.2-0.6, and length of longitudinal part equals 0.4-1.2 and distance from end face of wall longitudinal part to furnace inlet end amounts to 0.-0.6 width of respective recuperator. EFFECT: higher efficiency of heating and productivity of continuous furnace with upper and lower heating of metal ingots and reduced rejects due to cracks. 4 cl, 3 dwg , 1 tbl