Abstract: Disclosed is a surge control method and apparatus for a combustion air blower used with a metal melting furnace which includes a variable restriction on the blower inlet regulated by a pressure sensing means near the blower outlet.

Abstract: Disclosed is an improved high velocity dual fuel burner and a method for firing a vertical shaft metal melting furnace with gaseous or liquid fuel in which the burner nozzle is adapted to mix and ignite both types of fuels alternately or in combination by means of three concentric nozzles including a central oil spraying nozzle, an intermediate nozzle to supply natural gas and an outermost nozzle to supply combustion air.

Abstract: Disclosed is an improved high velocity dual fuel burner and a method for firing a vertical shaft metal melting furnace with gaseous or liquid fuel in which the burner nozzle is adapted to mix and ignite both types of fuels alternately or in combination by means of three concentric nozzles including a central oil spraying nozzle, an intermediate nozzle to supply natural gas and an outermost nozzle to supply combustion air.

Abstract: Disclosed herein is a method and an apparatus for improving the efficiency of conventional vertical shaft metal melting and refining furnaces by novel refractory arrangements to form a multiple level hearth which will support pieces of metal that have reached the hearth without being melted. With this invention there is even and complete distribution and diffusion of heat around and through these unmelted pieces of metal to effect their rapid melting. Thus unmelted pieces of metal cannot block burners or clog tapping outlets of vertical shaft furnaces, and undue restriction to the flow of molten metal in and from these furnaces is substantially avoided.