When storing a molten ferroalloy or molten nonferrous metal, the molten ferroalloy or molten nonferrous metal is denitrified or prevented from absorbing nitrogen, and thus post processing such as a denitrification process may not be performed. For this, there is provided a method of producing molten manganese-containing steel, the method including: preparing a molten ferroalloy or a molten nonferrous metal; maintaining the molten ferroalloy or the molten nonferrous metal at a temperature equal to or higher than a melting point thereof; and pouring the molten ferroalloy or the molten nonferrous metal into prepared molten steel, wherein in the maintaining of the molten ferroalloy or the molten nonferrous metal, the molten ferroalloy or the molten nonferrous metal is subjected to a nitrogen-absorption prevention process or a denitrification process.

When storing a molten ferroalloy or molten nonferrous metal, the molten ferroalloy or molten nonferrous metal is denitrified or prevented from absorbing nitrogen, and thus post processing such as a denitrification process may not be performed. For this, there is provided a method of producing molten manganese-containing steel, the method including: preparing a molten ferroalloy or a molten nonferrous metal; maintaining the molten ferroalloy or the molten nonferrous metal at a temperature equal to or higher than a melting point thereof; and pouring the molten ferroalloy or the molten nonferrous metal into prepared molten steel, wherein in the maintaining of the molten ferroalloy or the molten nonferrous metal, the molten ferroalloy or the molten nonferrous metal is subjected to a nitrogen-absorption prevention process or a denitrification process.

A clean and rapid smelting method in an electric arc furnace with full scrap steel, is suitable for smelting process of 30-300 t electric arc furnace with full scrap steel. In the smelting process of the electric arc furnace with full scrap steel, different kinds of mediums are injected by an injection lance which is installed inside refractory material of sidewall at the bottom of the electric arc furnace in different stages of smelting. Carburization is utilized in molten pool to accelerate melting down and improve carbon content of the molten pool at the stage of recarburizing and fluxing. A reaction in the molten pool is intensified at the stage of high efficiency dephosphorization and deep denitrogenation, to enhance efficient dephosphorization and deep denitrification of the reaction in the molten pool, thereby accelerating the smelting speed of the electric arc furnace with full scrap steel, improving effect of dephosphorization and denitrification.

A steel for induction hardening according to the present invention includes a chemical composition consisting of, in mass percent: C: 0.58 to 0.68%, Si: 0.70 to 1.40%, Mn: 0.20 to 1.40%, P: less than 0.020%, S: less than 0.020%, Al: 0.005 to 0.060%, N: 0.0020 to 0.0080%, O: 0.0015% or less, V: 0.01 to 0.25%, B: 0.0003 to 0.0040%, Ti: 0.010 to 0.050%, and Ca: 0.0005 to 0.005%, with the balance being Fe and impurities, and satisfies Formulae (1) to (3). The steel microstructure is made up of ferrite and pearlite. A ratio of a number of composite inclusions is 20% or more.
C+Si/7+Mn/5+Cr/9+Mo/2.51.05(1)
C+Si/10+Mn/20+Cr/250.70(2)
Cr/Si0.20(3)

A non-oriented silicon steel and a production method are provided. The non-oriented silicon steel is prepared by using the processes of molten iron desulfurization, converter smelting, RH refining, continuous casting, hot rolling, acid tandem rolling, annealing, coating and finishing, and a chemical composition is as follows in mass percent: C0.003%, S0.008%, Si: 0.35%+1, Mn: 0.15-0.25%, P: 0.04-0.06%, Sn: 0.015%+2, Nb0.004%, V0.004%, Ti0.005%, Mo0.004%, Cr0.03%, Ni0.03%, Cu0.03%, N0.003% and the balance of Fe and inevitable inclusions. The non-oriented silicon steel has the iron loss P.sub.1.5/505.5 W/kg and the magnetic induction intensity B.sub.50001.75 when having the thickness of 0.5 mm, and desulfurization is not needed in the RH refining process.

A non-oriented silicon steel and a production method are provided. The non-oriented silicon steel is prepared by using the processes of molten iron desulfurization, converter smelting, RH refining, continuous casting, hot rolling, acid tandem rolling, annealing, coating and finishing, and a chemical composition is as follows in mass percent: C0.003%, S0.008%, Si: 0.35%+1, Mn: 0.15-0.25%, P: 0.04-0.06%, Sn: 0.015%+2, Nb0.004%, V0.004%, Ti0.005%, Mo0.004%, Cr0.03%, Ni0.03%, Cu0.03%, N0.003% and the balance of Fe and inevitable inclusions. The non-oriented silicon steel has the iron loss P.sub.1.5/505.5 W/kg and the magnetic induction intensity B.sub.50001.75 when having the thickness of 0.5 mm, and desulfurization is not needed in the RH refining process.

Technologies are disclosed herein for cross-correlating metrics for anomaly root cause detection. Primary and secondary metrics associated with an anomaly are cross-correlated by first using the derivative of an interpolant of data points of the primary metric to identify a time window for analysis. Impact scores for the secondary metrics can be then be generated by computing the standard deviation of a derivative of data points of the secondary metrics during the identified time window. The impact scores can be utilized to collect data relating to the secondary metrics most likely to have caused the anomaly. Remedial action can then be taken based upon the collected data in order to address the root cause of the anomaly.

This diagnosis support apparatus is a diagnosis support apparatus of a vacuum degassing tank having an immersion tube that extends downward, the diagnosis support apparatus including a camera that is configured to capture an image of an inner circumferential surface of an immersion tube seen from below at an angle in a state of being disposed outside the inner circumferential surface of the immersion tube in a plan view and acquire the image as data and an image processor that is configured to be connected to the camera and carry out image-processing of the data.

A molten steel refining method includes throwing a powder to molten steel while heating the powder with a flame formed by combustion of a hydrocarbon gas at the leading end of a top blowing lance. The lance height of the top blowing lance (the distance between the static bath surface of the molten steel and the leading end of the lance) is controlled to 1.0 to 7.0 m, and the dynamic pressure P of a jet flow ejected from the top blowing lance calculated from equation (1) below is controlled to 20.0 kPa or more and 100.0 kPa or less. P=.sub.g U.sup.2/2 . . . (1) wherein P is the dynamic pressure (kPa) of the jet flow at an exit of the top blowing lance, .sub.g the density (kg/Nm.sup.3) of the jet flow, and U the velocity (m/sec) of the jet flow at the exit of the top blowing lance.

A molten steel refining method includes throwing a powder to molten steel while heating the powder with a flame formed by combustion of a hydrocarbon gas at the leading end of a top blowing lance. The lance height of the top blowing lance (the distance between the static bath surface of the molten steel and the leading end of the lance) is controlled to 1.0 to 7.0 m, and the dynamic pressure P of a jet flow ejected from the top blowing lance calculated from equation (1) below is controlled to 20.0 kPa or more and 100.0 kPa or less. P=.sub.g U.sup.2/2 . . . (1) wherein P is the dynamic pressure (kPa) of the jet flow at an exit of the top blowing lance, .sub.g the density (kg/Nm.sup.3) of the jet flow, and U the velocity (m/sec) of the jet flow at the exit of the top blowing lance.