Abstract: Metal is melted in melting vessels heated in a melting furnace by combustion of fuel and by exhaust gases from the combustion. In order to prevent evaporation, overheating and contamination of the melt, the exhaust gases of the melting furnace, including unburned fuel components of the exhaust gases, are directed through a channel of limited cross-sectional size into a melting chamber os substantially larger cross-sectional size. The hot gases are directed against the surface of melting vessels in the furnace and are allowed to expand in the melting chamber to transfer heat to melting vessels there. In addition, the hot gases are retained and the unburned components are burned in the melting chamber so that their heat capacity is given off to objects within the melting chamber to be stored in those objects to achieve a high degree of utilization of the fuel.

Abstract: Metal is melted in melting vessels heated in a melting furnace by combustion of fuel and by exhaust gases from the combustion. In order to prevent evaporation, overheating and contamination of the melt, the exhaust gases of the melting furnace, including unburned fuel components of the exhaust gases, are directed through a channel of limited cross-sectional size into a melting chamber of substantially larger cross-sectional size. The hot gases are directed against the surface of melting vessels in the furnace and are allowed to expand in the melting chamber to transfer heat to melting vessels there. In addition, the hot gases are retained and the unburned components are burned in the melting chamber so that their heat capacity is given off to objects within the melting chamber to be stored in those objects to achieve a high degree of utilization of the fuel.