Abstract: A molten metal component estimation device including: an input device configured to receive measurement information about a refining facility including measurement results regarding an optical characteristic; a model database that stores model expressions and model parameters, regarding a blowing process reaction, including a model expression and model parameters representing a relation between the oxygen efficiency in decarburization and a carbon concentration in a molten metal in the refining facility; and a processor configured to: estimate component concentrations of the molten metal including the carbon concentration in the molten metal by using the measurement information, the model expressions and the model parameters; estimate the carbon concentration in the molten metal based on the measurement results; and determine the model expression and the model parameters to be used when estimating the component concentrations of the molten metal, based on the estimation result of the carbon concentration in t

Abstract: A molten metal component estimation device including: an input device configured to receive measurement information about a refining facility including measurement results regarding an optical characteristic; a model database that stores model expressions and model parameters, regarding a blowing process reaction, including a model expression and model parameters representing a relation between the oxygen efficiency in decarburization and a carbon concentration in a molten metal in the refining facility; and a processor configured to: estimate component concentrations of the molten metal including the carbon concentration in the molten metal by using the measurement information, the model expressions and the model parameters; estimate the carbon concentration in the molten metal based on the measurement results; and determine the model expression and the model parameters to be used when estimating the component concentrations of the molten metal, based on the estimation result of the carbon concentration in t

Abstract: A method of monitoring a manufacturing status of an electric resistance welded pipe manufactured by shaping a steel strip into a pipe and butt welding both end parts of the steel strip in a width direction along a lengthwise direction includes: arranging an imaging unit in a gas shield nozzle having an opening opposing a region in which both of the end parts of the steel strip in the width direction are butt welded and shielding the region with inert gas by ejecting the inert gas onto the region through the opening, the imaging unit having a visual filed including the region; and determining quality of a butt-welded part based on an image shot by the imaging unit.

Abstract: A detecting method of optically detecting a surface defect of a moving steel material includes an irradiation step of irradiating an examination target part with illumination light beams from different directions by two or more distinguishable light sources whose light emission durations are set based on at least an allowable positional displacement of an image, the two or more distinguishable light sources repeatedly emitting light such that their light emission timings thereof do not overlap each other; and a detection step of obtaining images by reflected light beams of the respective illumination light beams and detecting a surface defect in the examination target part by executing subtraction processing between the obtained images.

Abstract: A surface inspection method for a steel pipe detects a surface defect on a hot steel pipe, and includes: an imaging step of imaging a self-luminous image of the hot steel pipe; a correcting step of making more uniform luminance variation in a circumferential direction of the self-luminous image and correcting the self-luminous image; and a detecting step of detecting a surface defect based on the self-luminous image corrected at the correcting step.

Abstract: A surface defect detecting method of optically detecting a surface defect of a steel material includes: an irradiation step of irradiating an examination target part with illumination light beams from different directions by using two or more distinguishable light sources; and a detection step of obtaining images by reflected light beams of the respective illumination light beams and detecting a surface defect in the examination target part by executing subtraction processing between the obtained images.

Abstract: A detecting method of optically detecting a surface defect of a moving steel material includes an irradiation step of irradiating an examination target part with illumination light beams from different directions by two or more distinguishable light sources whose light emission durations are set based on at least an allowable positional displacement of an image, the two or more distinguishable light sources repeatedly emitting light such that their light emission timings thereof do not overlap each other; and a detection step of obtaining images by reflected light beams of the respective illumination light beams and detecting a surface defect in the examination target part by executing subtraction processing between the obtained images.

Abstract: A method of detecting an abnormality in a blast furnace, wherein the abnormality causes clogging of a tuyere unit of the blast furnace, the method including capturing an image of a raceway unit through an in-furnace monitor window disposed at the tuyere unit; and determining that the abnormality has occurred when a brightness of the captured image is lower than or equal to a predetermined brightness threshold and a rate of decrease in the brightness is lower than or equal to a predetermined brightness-decrease-rate threshold.

Abstract: A laser beam welding diagnosis apparatus includes: an imaging unit configured to capture images of a laser beam welding penetration side of a laser beam welded portion at a predetermined time interval; a feature amount calculating unit configured to calculate, from an image captured by the imaging unit, a feature amount of a jetted portion accompanying laser beam welding penetration; a welding diagnosis unit configured to determine that a welding defect in the laser beam welded portion has occurred when values of the feature amounts of a predetermined area around the laser beam welded portion on the laser beam welding penetration side become equal to or less than a predetermined value for a predetermined duration or longer; and an output unit configured to output a welding quality state including the occurrence of the welding defect.

Abstract: A method of monitoring a manufacturing status of an electric resistance welded pipe manufactured by shaping a steel strip into a pipe and butt welding both end parts of the steel strip in a width direction along a lengthwise direction includes: arranging an imaging unit in a gas shield nozzle having an opening opposing a region in which both of the end parts of the steel strip in the width direction are butt welded and shielding the region with inert gas by ejecting the inert gas onto the region through the opening, the imaging unit having a visual filed including the region; and determining quality of a butt-welded part based on an image shot by the imaging unit.

Abstract: A surface defect detecting method of optically detecting a surface defect of a steel material includes: an irradiation step of irradiating an examination target part with illumination light beams from different directions by using two or more distinguishable light sources; and a detection step of obtaining images by reflected light beams of the respective illumination light beams and detecting a surface defect in the examination target part by executing subtraction processing between the obtained images.

Abstract: An oven wall shape measuring apparatus includes: a slit laser light source that is arranged in a thermally-insulated protection box having a slit-like window and emits slit-like laser light; a laser light mirror that reflects the laser light and irradiates an oven wall surface with the laser light via the window; an imaging mirror that reflects reflected light due to irradiation of the laser light and self-emitting light emitted from the oven wall surface, the reflected light and the self-emitting light entering the thermally-insulated protection box via the window; and an imaging device that images, via an optical filter, the self-emitting light and the reflected light that are reflected from the imaging mirror.

Abstract: A surface inspection method for a steel pipe detects a surface defect on a hot steel pipe, and includes: an imaging step of imaging a self-luminous image of the hot steel pipe; a correcting step of making more uniform luminance variation in a circumferential direction of the self-luminous image and correcting the self-luminous image; and a detecting step of detecting a surface defect based on the self-luminous image corrected at the correcting step.

Abstract: A welding position detecting apparatus for laser beam welding includes: an imaging device that captures, at a predetermined time interval, images of an irradiated portion of a welding material irradiated with a welding laser beam, and a surrounding area thereof, of a welding material; an image processing device that identifies a position of the irradiated portion irradiated with the welding laser beam by performing image processing calculating, from two or more images acquired by the imaging device, a direction and an amount of parallel movement of points in the images; and a display device that displays the position of the irradiated portion irradiated with the welding laser beam, the position being identified by the image processing device.

Abstract: A laser beam welding diagnosis apparatus includes: an imaging unit configured to capture images of a laser beam welding penetration side of a laser beam welded portion at a predetermined time interval; a feature amount calculating unit configured to calculate, from an image captured by the imaging unit, a feature amount of a jetted portion accompanying laser beam welding penetration; a welding diagnosis unit configured to determine that a welding defect in the laser beam welded portion has occurred when values of the feature amounts of a predetermined area around the laser beam welded portion on the laser beam welding penetration side become equal to or less than a predetermined value for a predetermined duration or longer; and an output unit configured to output a welding quality state including the occurrence of the welding defect.

Abstract: A method of detecting an abnormality in a blast furnace, wherein the abnormality causes clogging of a tuyere unit of the blast furnace, the method including capturing an image of a raceway unit through an in-furnace monitor window disposed at the tuyere unit; and determining that the abnormality has occurred when a brightness of the captured image is lower than or equal to a predetermined brightness threshold and a rate of decrease in the brightness is lower than or equal to a predetermined brightness-decrease-rate threshold.

Abstract: A welding position detecting apparatus for laser beam welding includes: an imaging device that captures, at a predetermined time interval, images of an irradiated portion of a welding material irradiated with a welding laser beam, and a surrounding area thereof, of a welding material; an image processing device that identifies a position of the irradiated portion irradiated with the welding laser beam by performing image processing calculating, from two or more images acquired by the imaging device, a direction and an amount of parallel movement of points in the images; and a display device that displays the position of the irradiated portion irradiated with the welding laser beam, the position being identified by the image processing device.

Abstract: There is provided a method for manufacturing a laser welded steel pipe in which the status of laser welding is accurately assessed, and the assessment is used to modify welding conditions, so that laser welded steel pipes can be manufactured at a high yield rate and in a stable manner. Irradiation point(s) of laser beam(s), with which the longitudinal edges are irradiated from the side of the outer surface, are monitored from the side of the inner surface of an open pipe, and then conditions of welding with the laser beam(s) are assessed to be kept unchanged if any keyhole is found penetrating out of the inner surface of the open pipe, or modified if no keyhole is found penetrating out of the inner surface of the open pipe.

Abstract: An oven wall shape measuring apparatus includes: a slit laser light source that is arranged in a thermally-insulated protection box having a slit-like window and emits slit-like laser light; a laser light mirror that reflects the laser light and irradiates an oven wall surface with the laser light via the window; an imaging mirror that reflects reflected light due to irradiation of the laser light and self-emitting light emitted from the oven wall surface, the reflected light and the self-emitting light entering the thermally-insulated protection box via the window; and an imaging device that images, via an optical filter, the self-emitting light and the reflected light that are reflected from the imaging mirror.

Abstract: There is provided a method for manufacturing a laser welded steel pipe in which the status of laser welding is accurately assessed, and the assessment is used to modify welding conditions, so that laser welded steel pipes can be manufactured at a high yield rate and in a stable manner. Irradiation point(s) of laser beam(s), with which the longitudinal edges are irradiated from the side of the outer surface, are monitored from the side of the inner surface of an open pipe, and then conditions of welding with the laser beam(s) are assessed to be kept unchanged if any keyhole is found penetrating out of the inner surface of the open pipe, or modified if no keyhole is found penetrating out of the inner surface of the open pipe.