According to some aspects, a system for producing a target molten metal composition is provided. The system includes a sorting device that sorts input pieces of metal based on a control signal. Sorted pieces of metal are melted in a furnace, and a sensor measures the composition of molten metal in the furnace and in response generates a control signal that is sent to the sorting device.

A production line comprises: a pretreatment system, a melting and refining system, and a casting system; magnesium alloy waste material passes in sequence through the pretreatment system, the melting and refining system, and the casting system, resulting in magnesium alloy ingots that conform to national standards. The production line for producing national-standard magnesium alloy ingots on the basis of magnesium alloy waste material processes magnesium alloy waste material, passing same through a pretreatment system, a preheating system a melting and refining system, a thermal insulation system, a casting system, and a post-treatment system; coatings and impurities on the surface of the magnesium alloy waste material are removed, and the material is processed into magnesium alloy ingots conforming to national standards; the pieces of equipment of each system are well-connected, the degree of automation is high, operation is simple, and production is highly efficient.

A production line comprises: a pretreatment system, a melting and refining system, and a casting system; magnesium alloy waste material passes in sequence through the pretreatment system, the melting and refining system, and the casting system, resulting in magnesium alloy ingots that conform to national standards. The production line for producing national-standard magnesium alloy ingots on the basis of magnesium alloy waste material processes magnesium alloy waste material, passing same through a pretreatment system, a preheating system a melting and refining system, a thermal insulation system, a casting system, and a post-treatment system; coatings and impurities on the surface of the magnesium alloy waste material are removed, and the material is processed into magnesium alloy ingots conforming to national standards; the pieces of equipment of each system are well-connected, the degree of automation is high, operation is simple, and production is highly efficient.

In production of a reactive metal using a melting furnace for producing metal having a hearth, ingots can be efficiently produced by efficiently cooling the ingots extracted from the mold provided in the melting furnace. In addition, an apparatus structure in which multiple ingots can be produced with high efficiency and high quality from one hearth, is provided. A melting furnace for producing metal is provided, the furnace has a hearth for having molten metal formed by melting raw material, a mold in which the molten metal is poured, an extracting jig which is provided below the mold for extracting ingot cooled and solidified downwardly, a cooling member for cooling the ingot extracted downwardly of the mold, and an outer case for keeping the hearth, the mold, the extracting jig, and the cooling member separated from the air, wherein at least one mold and extracting jig are provided in the outer case, and the cooling member is provided between the outer case and the ingot, or between the multiple ingots.

Method for producing ingots made of metal having cross-sectional areas of at least 0.10 m.sup.2 of a round, square or rectangular shape through casting of metal or molten steel either directly from the casting ladle (1) or using a fireproof lined intermediate vessel (3) in a short, water-cooled ingot mold open downwards (4) and withdrawing of the solidified ingot (6) from the same downwardly movable withdrawing tool (8), wherein the casting process is continued with a casting rate determined in accordance with the casting cross-section for as long as the desired or maximum ingot length determined by the height of lift of the withdrawing tool (8) is reached, and additional liquid metal is fed at the end of the regular casting process to an extent that at least the contraction of the metal and steel melt occurring during solidification is balanced during, and whereby after completion of the regular casting process and completion of the ingot withdrawal, the casting process is continued with a casting rate reduced by at least the Factor 10 from the heatable casting ladle (1) or the heatable intermediate vessel (3) or a distribution container, and is reduced progressively or continuously at the end of the solidification to 10% the rate at the start of the additional casting.

For continuously casting an ingot of titanium or titanium alloy, molten titanium or titanium alloy is poured into a top opening of a bottomless mold with a circular cross-sectional shape, the solidified molten metal in the mold is pulled downward from the mold, a plurality of plasma torches disposed on an upper side of molten metal in the mold such that their centers are located directly vertically above the molten metal in the mold, are operated to generate plasma arcs that heat the molten metal in the mold, and the plasma torches are moved in a horizontal direction above a melt surface of the molten metal in the mold, along a trajectory located directly vertically above the molten metal in the mold, while keeping a mutual distance between the respective plasma torches such that the plasma torches do not interfere with each other.

A control device controls temperatures of heaters included in a casting furnace. The casting furnace includes a mold to receive an inorganic material and the heaters surrounding the mold to heat the mold and cause the inorganic material to melt and solidify from a bottom to manufacture an ingot. The heaters include an upper heater located above the mold, a lateral upper heater located above and lateral to the mold, and a lateral lower heater located lateral to the mold below the lateral upper heater. The control device includes a heater controller that controls, in a solidification process of the inorganic material, temperatures of the upper heater, the lateral upper heater, and the lateral lower heater based on a solidification ratio of the inorganic material and at least one of a solidification rate of the inorganic material or interface profile information indicating a solid-liquid interface profile of the inorganic material.

A control device controls temperatures of heaters included in a casting furnace. The casting furnace includes a mold to receive an inorganic material and the heaters surrounding the mold to heat the mold and cause the inorganic material to melt and solidify from a bottom to manufacture an ingot. The heaters include an upper heater located above the mold, a lateral upper heater located above and lateral to the mold, and a lateral lower heater located lateral to the mold below the lateral upper heater. The control device includes a heater controller that controls, in a solidification process of the inorganic material, temperatures of the upper heater, the lateral upper heater, and the lateral lower heater based on a solidification ratio of the inorganic material and at least one of a solidification rate of the inorganic material or interface profile information indicating a solid-liquid interface profile of the inorganic material.