A breakout prediction method includes: a step of inputting a dimension of a solid product withdrawn from a mold in a continuous casting machine; a step of detecting a temperature of the mold by a plurality of thermometers embedded in the mold; a step of executing interpolation processing on the detected temperatures detected by the plurality of thermometers according to the dimension of the solid product; a step of calculating, based on the temperatures calculated by executing the interpolation processing, a component in a direction orthogonal to an influence coefficient vector obtained by principal component analysis as a degree of deviation from during a normal operation in which a breakout has not occurred; and a step of predicting a breakout based on the degree of deviation.

Process control of intense stirring along a solidification front and adjustments in casting speeds during direct chill casting of 7xxx series alloys can decrease an ingot’s cracking susceptibility. Intense stirring control is used to reduce the thickness of the solidification front, promote agglomeration of hydrogen gas rejected at the solidification front, remove impurities rejected at the solidification front, and improve grain size. Intense stirring control is used to operate at faster casting speeds without risk of increasing the thickness of the solidification front. Optional reheating during casting to promote dispersoid formation is used to generate a high-strength zone of dispersoid-strengthened solidified metal in the outer periphery of the ingot, which can further decrease the ingot’s susceptibility to cracking.

This method for balancing a flow of liquid steel into a casting mold, in which the steel is introduced into the casting mold from a tundish through a protective nozzle which opens below the steel level into the casting mold, comprises the following steps: a) acquiring a set of characteristics of the flow in the casting mold, b) comparing the flow characteristics acquired in the previous step with a predefined model and determining the adjustment actions to take in order to balance the flow, and c) adjusting the flow.

An in-mold solidified shell thickness estimation apparatus includes: an input device; a model database configured to store a model formula and a parameter related to a solidification reaction of a molten steel inside a mold of a continuous casting facility; and a heat transfer model calculator configured to estimate an in-mold solidified shell thickness by calculating temperature distributions of the mold and of the molten steel inside the mold by solving a three-dimensional unsteady heat transfer equation. The heat transfer model calculator is configured to correct errors in a temperature of a mold copper plate and in an amount of heat removed from the mold, by correcting an overall heat transfer coefficient between the mold copper plate and the solidified shell.

A continuously casting method including arranging temperature measuring elements according to specified conditions, selecting as evaluation targets for temperatures of copper plates on a wide face of mold values measured by the temperature measuring elements arranged closer to a center in a width direction of a cast slab than short sides of the cast slab under continuous casting at levels of 50 mm or more lower in a slab withdrawal direction than a meniscus of a molten steel in a mold, and adjusting a casting condition such that a standard deviation of the values measured over the width direction of the copper plates on the wide face of mold at a same level in the slab withdrawal direction is 20° C. or lower.

A method, an apparatus and a computer readable-medium for monitoring a continuous steel casting process where molten steel is poured from a ladle into a tundish to be transferred through an exit nozzle into a mold. The method includes obtaining a critical superheat temperature value for the molten steel; measuring temperature values of the molten steel over a time period; determining superheat temperature values corresponding to the measured temperature values by comparing the measured temperature values with a liquidus temperature of the molten steel; and predicting a forecast time instance when the critical superheat temperature value is reached.

Provided is a meniscus flow control device includes: a meniscus flow detection unit for detecting, in a meniscus flow form of molten steel, relative temperature values for positions measured by temperature measurers, and relatively comparing the temperature values measured by the temperature measurers to thereby determine the flow state of the molten steel meniscus to be normal or abnormal; a magnetic field generation unit, installed outside a mold, for generating a magnetic field and controlling the flow of the molten steel by the magnetic field; and a flow control unit for maintaining the operation of the magnetic field generation unit in the current state when the meniscus flow state detected by the meniscus flow detection unit is determined to be normal, and for controlling the magnetic field generation unit to adjust the meniscus flow to be normal when the detected meniscus flow state is determined to be abnormal.

A steel sheet having a specified chemical composition and a tensile strength of 1,320 MPa or more, and methods for producing the steel sheet. The steel sheet has a specified microstructure including martensite and bainite, the total area fraction of the martensite and the bainite being 95% or more and 100% or less, the balance being one or more selected from ferrite and retained austenite. The forumulae [% Ti]+[% Nb]>0.007 and [% Ti]×[% Nb].sup.2≤7.5×10.sup.−6 are satisfied in the chemical composition.

An apparatus for the automatic startup of a continuous casting line, including a vessel which is connected to a tip by means of a gate, the tip feeding a casting housing. The apparatus includes a laser device which measures the level of the metal within the vessel, a level control device, which adjusts the introduction of liquid metal into the vessel, a gate actuator to control the gate for providing a barrier between the vessel and the tip, a transducer for the temperature of the metal inside the vessel, and a PLC which receives data from the temperature transducer and from the laser device to control the level control device and the gate actuator, so as to adjust the vessel metal level to ensure a correct and continuous flow of metal toward the casting cylinders, in order to avoid poor diffusion of the metal inside the tip.

A heat flux derivation unit (202) derives a value q.sub.y of a y-axis direction component of a heat flux vector. A molten metal surface level derivation unit (203) derives, as a molten metal surface level, a position where the absolute value of the value q.sub.y of the y-axis direction component of the heat flux vector whose y-axis component vector is in a direction opposite to a casting direction is maximum.