The invention is directed to a method for processing asbestos-containing steel scrap into useful products, which products can be handled in a safe manner. In accordance with the present invention the asbestos-containing steel scrap is melted in a furnace, which results in destruction of the asbestos fibers. It has been found possible to carry out such a process in an economically feasible manner. In accordance with the invention asbestos-containing steel is heated to high temperature so that the steel melts. As a result the asbestos will be converted into harmless material, which allows for safe handling and processing of the resulting products.

An immersion-type burner heater includes a heater protection tube that is installed so as to penetrate a furnace wall or an upper lid of the molten-metal holding furnace with the tip end thereof being closed; an inner cylindrical member arranged inside the tube so as to define a combustion flow passage S between the tube and itself with the tip end side thereof being open and the inside thereof serving as an exhaust gas flow passage; and a gas burner part supplying fuel gas and air to the combustion flow passage. A helically extending projecting part is provided on at least one of the outer peripheral surface of the member and the inner peripheral surface of the tube at a position that is closer to its tip end side than to the part penetrating the furnace wall or the upper lid.

An immersion-type burner heater includes a heater protection tube that is installed so as to penetrate a furnace wall or an upper lid of the molten-metal holding furnace with the tip end thereof being closed; an inner cylindrical member arranged inside the tube so as to define a combustion flow passage S between the tube and itself with the tip end side thereof being open and the inside thereof serving as an exhaust gas flow passage; and a gas burner part supplying fuel gas and air to the combustion flow passage. A helically extending projecting part is provided on at least one of the outer peripheral surface of the member and the inner peripheral surface of the tube at a position that is closer to its tip end side than to the part penetrating the furnace wall or the upper lid.

[Problem] To provide: a molten metal plating furnace that can increase plating quality and work efficiency; a system for producing and method for producing a metal plated product; and a metal plated steel tube obtained by means of the method for producing. [Solution] The system for producing has at least one plating implementation unit that performs molten metal plating of a plating processing subject, and at least one plating implementation unit has a plating bath and a heating device for heating the plating bath, wherein in the heating device, an array of fuel filling openings and an array of air filling openings are formed that are facing in a manner so as to discharge air and fuel to a combustion region in common along a combustion chamber, the effective opening cross-sectional size of at least the majority of the openings of at least one of the opening arrays can be adjusted by means of an adjustment mechanism for adjusting the extent of a medium filling opening array, and when the size of both opening arrays can be adjusted, individual adjustment of the arrays is possible.

Provided is a heater protection tube for use with a molten metal holding furnace with heat dissipation and insulating properties. A heat protection tube 31 has a distal tapered cylindrical portion 35 corresponding to the inside tapered cylindrical portion 21 and a proximal non-tapered cylindrical portion 36 corresponding to the outside non-tapered cylindrical portion 22. The heater protection tube (31) is configured so that it can be mounted in the side wall (13) with the distal tapered cylindrical portion (35) located at the inside tapered cylindrical portion (21) and with the proximal non-tapered cylindrical portion (36) located at the outside non-tapered cylindrical portion (22).

Provided is a heater protection tube for use with a molten metal holding furnace with heat dissipation and insulating properties. A heat protection tube 31 has a distal tapered cylindrical portion 35 corresponding to the inside tapered cylindrical portion 21 and a proximal non-tapered cylindrical portion 36 corresponding to the outside non-tapered cylindrical portion 22. The heater protection tube (31) is configured so that it can be mounted in the side wall (13) with the distal tapered cylindrical portion (35) located at the inside tapered cylindrical portion (21) and with the proximal non-tapered cylindrical portion (36) located at the outside non-tapered cylindrical portion (22).

A method of melting an aluminum charge having no more that 4% salt by mass, including during a melting phase, introducing fuel and oxidant via a burner operating at a first firing rate, the fuel and oxidant reacting to form a combustion zone above the aluminum charge, terminating the melting phase and commencing a transition phase when the aluminum charge is nearly completely molten, during the transition phase, reducing the firing rate of the burner to a second firing rate lower than the first firing rate, introducing a non-oxidizing gas at a first velocity to form a non-oxidizing zone between the combustion zone and the aluminum charge, and allowing the aluminum charge to become completely molten, and terminating the transition phase and commencing a tapping phase after the aluminum charge has become completely molten, and during the tapping phase, pouring the molten aluminum charge out of the furnace.

The invention relates to a device for heating molten metal by the use of a heater that can be immersed into the molten metal. This immersion heater includes an outer cover formed of one or more materials resistant to the molten metal in which the immersion heater is to be used, and a heating element inside of the outer cover, where the heating element is protected from contacting the molten metal.

The invention relates to a device for heating molten metal by the use of a heater that can be immersed into the molten metal. This immersion heater includes an outer cover formed of one or more materials resistant to the molten metal in which the immersion heater is to be used, and a heating element inside of the outer cover, where the heating element is protected from contacting the molten metal.

An apparatus comprising an induction furnace with a thermally and electrically conductive or non-conductive crucible containing an electrically conductive ferrous or non-ferrous material is provided with at least one bottom induction coil, one side induction coil and one top induction coil disposed exteriorly around the bottom, side and over the top surface of the material in the conductive or non-conductive crucible to provide a non-contact temperature boost or a flow rate boost to the material by selectively energizing a combination of the coils. The induction furnace is particularly useful for electrically conductive materials having a relatively low value of thermal conductivity, such as aluminum or an aluminum alloy.