Abstract: Device for heating metal material includes an elongated DFI burner arranged to be driven with gaseous oxidant and gaseous fuel and to be displaceable and longitudinally arranged with respect to the metal material. The burner includes longitudinal tubular vessels for fuel and for oxidant, arranged in parallel to one another and relative to the surface of the metal material. Each of these vessels has an opening through which the fuel and oxidant flow out and then converge in an ignition zone outside the respective vessels, where a flame is generated. Supply devices are arranged via a regulator to keep the pressure constant throughout the respective vessel during operation. Each of the vessels has a longitudinally displaceable piston for controlling the longitudinal extension of the flame in the longitudinal direction of the vessels.

Abstract: Device for heating a metal material, includes an elongated DFI burner device, arranged to be driven with gaseous oxidant and gaseous fuel and to be displaceable and longitudinally arranged with respect to the metal material. The device has supply devices for fuel and oxidant. The burner device includes longitudinal, tubular vessels for fuel and for oxidant, arranged in parallel to one another and relative to the surface of the metal material. Each vessel has one or more openings arranged along the vessel, through which the fuel and oxidant are arranged to flow out and then converge in an ignition zone outside the respective vessels, where a flame is generated. The respective supply devices are arranged via a regulator to keep the pressure constant throughout the vessel in question during operation. Each vessel has a longitudinally displaceable piston for controlling the longitudinal extension of the flame in the longitudinal direction of the vessels.

Abstract: A method of heat treating stainless steel in the form of blanks, piping, tubing, strip, or wire-like material, after rolling the material, and in a heat treatment furnace at a temperature higher than about 900° C. The material is subjected to a preheating stage and a final heating stage, wherein in the preheating stage flames from burners are directed toward the surface of the material to impinge on the surface. Burners situated in the preheating stage are supplied with a fuel that burns with the aid of an oxidizing gas that contains gaseous oxygen. The material is held in the preheating stage long enough to obtain at least some degree of oxidation on the surface of the material, and the material is heated further in a following, final heating stage by burners situated in a furnace and that are supplied with a fuel and an oxidizing gas.

Abstract: A method of heat treating stainless steel in the form of blanks, piping, tubing, strip, or wire-like material, after rolling the material, and in a heat treatment furnace at a temperature higher than about 900° C. The material is subjected to a preheating stage and a final heating stage, wherein in the preheating stage flames from burners are directed toward the surface of the material to impinge on the surface. Burners situated in the preheating stage are supplied with a fuel that burns with the aid of an oxidizing gas that contains gaseous oxygen. The material is held in the preheating stage long enough to obtain at least some degree of oxidation on the surface of the material, and the material is heated further in a following, final heating stage by burners situated in a furnace and that are supplied with a fuel and an oxidizing gas.

Abstract: A method for heat-treating steel, primarily strip-like or rod-like steel material, such as steel strip, steel sheet, steel rod or steel wire which have been rolled and heated in an oven or furnace to a surface temperature above about 900 degrees C. and thereafter cooled and optionally treated in an electrolyte bath and/or acid bath. The oven burners are fired with a liquid or a gaseous fuel which is burned with the aid of a gas that contains at least 85 percent by volume oxygen and at most 10 percent by volume nitrogen.

Abstract: A process for producing pig iron from iron ore concentrate, in a reactor vessel into which iron ore concentrate, coal, oxygen gas and slag formers are injected beneath the surface of a molten iron bath. According to the invention, the ratio CO.sub.2 /CO in the waste gas (11) from the reactor (2) is increased to a value higher than corresponding to the condition of equilibrium at atmospheric pressure. As a result greater heat is generated in the bath for a specific coal amount. The injected amount of coal in relation to injected amount of concentrate is predetermined for finally reducing pre-reduced iron ore concentrate (4) in the reactor (2). According to the invention, CO and H.sub.2 in the exhaust gas is passed to a pre-reduction step (1), where unreduced iron ore concentrate is pre-reduced and thereafter can be injected into the reactor.According to a preferred embodiment, the reactor (2) is pressurized to cause the CO.sub.2 /CO ratio to increase.

Abstract: A method of gasifying carbon (C) in the form of coal, hydrocarbons and/or hydrocarbon compounds, comprising the steps of into a reactor vessel holding a molten iron bath to inject carbon, oxygen and iron oxides beneath the surface of the molten iron bath, where the iron oxides constitute a coolant and where carbon is injected in a stoichiometric excess relative to oxygen included in the bath in the form of oxides, and where the molten iron bath has such a carbon content that it solves-in carbon. According to the invention, the reactor vessel is caused to have an inner total pressure of 2 to 50 bar, preferably 4 to 10 bar.Hereby the gas production and the production of pig iron increase. Furthermore, the dust formation and the lining wear are reduced substantially.