The invention provides a calculation method for operating resistance in a dual-electrode DC electric-smelting furnace for magnesium, including the following steps of: calculating a raw material resistance: simplifying a raw material model as an electrode-centered cylindrical model, determining an electric-field strength of each point in an electric field generated by a raw material layer around an electrode in the cylindrical model, calculating a raw material voltage between two electrodes according to the electric-field strength of each point in the electric field, and further obtaining the raw material resistance between the two electrodes; calculating an electric arc-resistance relation model: determining a relation between an actual electric arc length and a distance from the electrode to a surface of a smelting pool, and calculating a relation between an electric arc voltage and the actual electric arc length, namely the electric arc-resistance relation model; and calculating a smelting pool resistance, namely the sum in series of the smelting pool resistance of the two electrodes.

An example embodiment of the present invention provides a system for preheating ferromagnetic scrap. The system can include a preheating unit that is configured to hold ferromagnetic scrap and to receive hot gases. The preheating unit may include a removable cover that can include an electrical magnet system. The electrical magnet system can comprise an electrical magnet, a lifting device configured to lower and raise the electrical magnet, a power system configured to provide electrical power to the electrical magnet, and an electrical control system configured to operate the magnet. A hot gases cleaning system may be fluidly connected to the preheating unit.

An example embodiment of the present invention provides a system for preheating ferromagnetic scrap. The system can include a preheating unit that is configured to hold ferromagnetic scrap and to receive hot gases. The preheating unit may include a removable cover that can include an electrical magnet system. The electrical magnet system can comprise an electrical magnet, a lifting device configured to lower and raise the electrical magnet, a power system configured to provide electrical power to the electrical magnet, and an electrical control system configured to operate the magnet. A hot gases cleaning system may be fluidly connected to the preheating unit.

A method for identifying, classifying, and sending notification of an electric arc furnace's (EAF) anomalies to improve the EAF efficiency. The method includes the steps of establishing baseline state measurements of the EAF, receiving new state measurements of the EAF and statistically testing the new state measurements against the baseline state measurements. The method further includes the steps of identifying as an anomaly a failed statistical test, classifying the identified anomaly and sending notification of the classified anomaly to a configurable list of recipients.

A method for identifying, classifying, and sending notification of an electric arc furnace's (EAF) anomalies to improve the EAF efficiency. The method includes the steps of establishing baseline state measurements of the EAF, receiving new state measurements of the EAF and statistically testing the new state measurements against the baseline state measurements. The method further includes the steps of identifying as an anomaly a failed statistical test, classifying the identified anomaly and sending notification of the classified anomaly to a configurable list of recipients.

An apparatus is disclosed for a split spray-cooled roof for a tilting metallurgical furnace. The split spray-cooled roof has a center, a first hollow metal roof section and a second hollow metal roof section. The first and second hollow roof sections are attached together along a prescription split line. The prescription split line having a first split line and a second split line, wherein the first split line is not aligned with the second split line and wherein the first and second split line are not aligned with the center.

An apparatus is disclosed for a split spray-cooled roof for a tilting metallurgical furnace. The split spray-cooled roof has a center, a first hollow metal roof section and a second hollow metal roof section. The first and second hollow roof sections are attached together along a prescription split line. The prescription split line having a first split line and a second split line, wherein the first split line is not aligned with the second split line and wherein the first and second split line are not aligned with the center.

An apparatus is disclosed for a split spray-cooled roof for a tilting metallurgical furnace. The split spray-cooled roof has a center, a first hollow metal roof section and a second hollow metal roof section. The first and second hollow roof sections are attached together along a prescription split line. The prescription split line having a first split line and a second split line, wherein the first split line is not aligned with the second split line and wherein the first and second split line are not aligned with the center.

An apparatus is disclosed for a split spray-cooled roof for a tilting metallurgical furnace. The split spray-cooled roof has a center, a first hollow metal roof section and a second hollow metal roof section. The first and second hollow roof sections are attached together along a prescription split line. The prescription split line having a first split line and a second split line, wherein the first split line is not aligned with the second split line and wherein the first and second split line are not aligned with the center.

A control system for a vacuum arc remelting (VAR) process for a metal includes a direct current (DC) power source, a ram drive, voltage drip short sensor, and a controller, which includes a processor. The drip short sensor may be configured to measure a drip short frequency of the electric arc over a period of time. The controller is configured to determine a real time arc gap length between the electrode tip and the melt pool based on a correlation between the drip short frequency and arc gap length. The controller is further configured to control power input to the electrode by the DC power supply by determining an input power level to input to the electrode based on the real time arc gap length, the input power level configured to generate a desired arc gap length, by the DC power supply, at the input power level.