Abstract: An arrangement and method for determining the height position of a vertically movable electrode (2) in an arc furnace (1). The arrangement includes an elongated, flexible element (9), preferably a heavy chain, whose one end is attached to a first attachment point on the movable electrode (2). The other end of the chain is attached to a fixed second attachment point. The total weight of those flexible element parts that are carried by the movable and the fixed attachment points respectively will vary in response to vertical movement of the electrode. The arrangement also includes load cell for sensing the part of the total weight supported by the fixed attachment point, for determining the height position of the electrode (2).

Abstract: The invention relates to a method of manufacturing stainless steel, by treating a raw high-carbon steel in a first stage with a gaseous mixture that contains oxygen and inert gas, therewith lowering the carbon content of the raw steel to a value of 0.2-0.1%. The steel bath is then treated in a second stage with solely an inert gas, until the carbon content has fallen to the desired value. The invention is characterized in that the steel bath is treated in the first stage alternately with an oxygen-rich gas and with an inert gas, until the carbon content of the steel has fallen to the desired value.

Abstract: A ladle arrangement intended for use when treating a metal melt, in which gas or gas/powder mixture is delivered to the melt (2) which substantially fills the ladle (1), and departing gases are extracted by suction through a hood mounted above the ladle. The inventive ladle arrangement is effective to permit the gas or gas/powder mixture to be delivered to the melt in a large volumetric flow, wherewith the melt will bubble and splash vigorously. For the purpose of restricting the effects of these melt splashes to a defined space above the melt (2), the gas extraction hood has the form of a lid (7) which is intended to substantially seal against the upper edge of the ladle (1). The lid is configured so that the volume (6) defined by the lid above the melt will correspond to a substantial part, preferably at least half, of the volume of the melt (2) in the ladle (1). The side surfaces of the lid (7) define splash droplet pathway operative to return the droplets to the melt in the ladle.

Abstract: An arrangement for use when treating a melt, particularly a metal melt (2) in a converter (1) with gas, for the purpose of intensifying and rendering effective the contact between gas and melt and to produce effective admixture of the gas with the melt. The arrangement includes at least one nozzle (5) which discharges into the melt (2) and which is operative to deliver the gas in the form of at least one high pressure jet. For the purpose of producing a high gas pressure of such value as to produce a finely-divided mixture of gas and melt in a jet zone (10) in the melt (2), a pressure-elevating device (9) is incorporated in the fluid line connected to the nozzle (5). The invention also relates to a method of treating a metal melt in a converter.

Abstract: A method for producing raw iron from iron-bearing oxidic material, comprising finally reducing the iron oxide by charging the iron oxide, coal, oxygen gas and slag-forming flux to a molten iron bath contained in at least one reactor vessel, a final reduction reactor (2) for final reduction of the iron oxide, and pre-reducing primarily non-reduced iron oxide in a pre-reduction stage (1), and subsequently charging the pre-reduced iron oxide to the reactor, and generating reduction gas (17) for the aforesaid pre-reduction process. The method is particularly characterized in that reduction gas for the pre-reduction process (1) is generated by a separate gas generating process (3) effected in at least one reactor (3), a gas generating reactor, separate from the final reduction reactor or reactors (2). The invention also relates to a plant for carrying out the method.