Abstract: The burner for metallurgical furnaces comprises a main combustion chamber (7) and an auxiliary combustion chamber (5) presenting a plurality of outlet channels (6) communicating with the main combustion chamber (7). To the main combustion chamber there is fed in a pulsating manner a primary mix of fuel gas and air in stoichiometric ratio, and, during the intervals between the feed pulses, a secondary mix of fuel gas and air with a coefficient of excess air of 1.15 to 1.35 and at a rate of flow corresponding to 1 to 3% of the nominal rate of flow. To the auxiliary combustion chamber (5) there is instead continuously fed an auxiliary mix of fuel gas and air with a coefficient of excess air of 0.65 to 0.85 and at a rate of flow corresponding to 1 to 3% of the rate of flow of the primary mix. The combustion products of the auxiliary mix stay in the auxiliary combustion chamber (5) for a very short time, more particularly for about from 0.005 to 0.01 sec.

Abstract: In a rocking-beam type furnace which comprises fixed support beams which extend lengthwise of the furnace and conveyor beams which are parallel to the fixed beams and which can be raised and lowered and moved back and forth, the upper edges of the fixed beams and of the conveyor beams are provided with transverse billet locating notches having inclined billet supporting surfaces so that billets are intermittently and progressively rotated about their longitudinal axes during their passage through the furnace until they have performed at least one full rotation.