Abstract: The present invention provides a cooling control method which comprises calculating cooling conditions required for cooling the steel plate to a predetermined temperature for a plurality of positions inside a cooling apparatus based on measured temperatures at a time when the steel plate passes through the cooling apparatus by a thermometer disposed at the entry-side of the cooling apparatus and setting a cooling schedule, calculating a heat transfer coefficient from the set temperature and a cooling water density for cooling one surface of the steel plate, calculating a cooling top water density from the calculated heat transfer coefficient, and controlling the amounts of cooling water of the cooling apparatus based on the ratio of the cooling bottom water density and cooling top water density so as to cool the steel plate to a predetermined cooling end temperature.

Abstract: A cooling method of a thick-gauge steel plate by spraying water from a plurality of spray nozzles on the top and bottom surfaces of the thick-gauge steel plate conveyed between the adjoining pairs of constraining rolls, each comprising a top roll and bottom roll, constraining and conveying the steel plate so as to efficiently cool the top and bottom surfaces of thick-gauge steel plate to secure symmetry of temperatures of the top and bottom surfaces and uniformity of temperature in the plate width direction and achieve improvement of flatness of thick-gauge steel plate and uniformity of quality.

Abstract: A cooling method of a thick-gauge steel plate by spraying water from a plurality of spray nozzles on the top and bottom surfaces of the thick-gauge steel plate conveyed between the adjoining pairs of constraining rolls, each comprising a top roll and bottom roll, constraining and conveying the steel plate so as to efficiently cool the top and bottom surfaces of thick-gauge steel plate to secure symmetry of temperatures of the top and bottom surfaces and uniformity of temperature in the plate width direction and achieve improvement of flatness of thick-gauge steel plate and uniformity of quality.

Abstract: The present invention provides a steel plate cooling method, in controlled cooling of thick-gauge steel plate, which uniformly cools steel plate over its entire length and eliminates plate warping, that is, a method of conveying and cooling the top and bottom surfaces of steel plate in a high temperature state after hot rolling while constraining the high temperature rolled steel plate by a plurality of sets or top and bottom draining rolls, wherein cooling nozzles having a large number of nozzle openings and individually or simultaneously spraying the two fluids of air and water are used to cool the steel plate, the cooling method of steel plate characterized by giving a stable pattern by driving out air trying to invade the path of flow reaching the front end of the cooling apparatus when the water which is fed is low in amount or low in pressure.

Abstract: The present invention relates to a method of arranging and setting spray nozzles in a cooling apparatus comprising a plurality of pairs of constraining rolls for constraining and conveying a hot steel plate and one or more lines of spray nozzles between the pair of constraining rolls, each line having a plurality of spray nozzles and is disposed in a direction perpendicular to processing, and to the cooling apparatus and the method of cooling. The invention is characterized in that the spray nozzles are arranged such that a distribution of values ?Pn between two edges of the steel plate in the direction perpendicular to processing is not less than 80% of its highest value, with P being cooling water impact pressure on the cooling surface, ?Pn being the value of n power of P integrated in the processing direction between the pairs of constraining rolls, and 0.05?n?0.2.

Abstract: The present invention relates to an apparatus for cooling hot steel plate applied for controlled cooling of hot steel plate, obtained by hot rolling, while processing it constrained by constraining rolls and obtaining a steel material excellent and uniform in shape characteristics and provides a method of arranging and setting spray nozzles enabling uniform cooling in a direction perpendicular to processing and provides a method of arranging and setting spray nozzles of a spray cooling apparatus using two or more types of nozzles differing in amounts of water and spray regions to obtain a broad range of adjustment of amounts of water, wherein the spray nozzles are arranged so that a value of an n power of the impact pressures of the cooling water sprayed from the spray on the cooling surface integrated in the processing direction between pairs of constraining rolls becomes within ?20% of the highest value in the direction perpendicular to processing, where, 0.05?n?0.

Abstract: The present invention relates to an apparatus for cooling a hot steel plate which is processed and constrained by constraining rolls and a method of arranging and setting spray nozzles enabling uniform cooling in a direction perpendicular to processing. In the apparatus and method of the invention, the spray nozzles are arranged so that a value of n power of the impact pressure of the cooling water on the cooling surface integrated in the processing direction between pairs of constraining rolls becomes within ?20% of the highest value in the direction perpendicular to processing, where 0.05?n?0.2.

Abstract: An apparatus for controlled cooling of hot steel plate while constraining and conveying the plate by constraining rolls horizontally which is inexpensive and enabling continuous control of the cooling ability over a broad range, that is, a cooling apparatus for spraying hot steel plate hot rolled and transferred between pairs of constraining rolls with cooling water from pluralities of lines of spray nozzles so as to cool the same, which apparatus has lines of gentle cooling spray nozzles and lines of strong cooling spray nozzles with different orifice shapes and enables continuous control of the cooling ability over a broad range due to the fact that a maximum cooling water impact pressure integrated value of the lines of gentle cooling spray nozzles and a minimum cooling water impact pressure integrated value of the lines of strong cooling spray nozzles are continuous.

Abstract: A cooling control method which quickly controls the amounts of cooling water sprayed from top and bottom surfaces of the cooling apparatus when cooling steel plate to a predetermined cooling end temperature so as prevent shape deterioration of steel plate occurring due to the difference of cooling rates between the top surface and the bottom surface with a high precision, that is, a cooling control method of calculating cooling conditions required for cooling the steel plate to a predetermined temperature for a plurality of positions inside the cooling apparatus based on measured temperatures at a time when the steel plate passes through the cooling apparatus by a thermometer disposed at the entry-side of the cooling apparatus and setting a cooling schedule, calculating a heat transfer coefficient from the set temperature and a cooling bottom water density, calculating a cooling top water density from the calculated heat transfer coefficient, and controlling the amounts of cooling water of the cooling apparat

Abstract: An apparatus for controlled cooling of hot steel plate while constraining and conveying the plate by constraining rolls horizontally which is inexpensive and enabling continuous control of the cooling ability over a broad range, that is, a cooling apparatus for spraying hot steel plate hot rolled and transferred between pairs of constraining rolls with cooling water from pluralities of lines of spray nozzles so as to cool the same, which apparatus has lines of gentle cooling spray nozzles and lines of strong cooling spray nozzles with different orifice shapes and enables continuous control of the cooling ability over a broad range due to the fact that a maximum cooling water impact pressure integrated value of the lines of gentle cooling spray nozzles and a minimum cooling water impact pressure integrated value of the lines of strong cooling spray nozzles are continuous.

Abstract: The present invention provides a steel plate cooling method, in controlled cooling of thick-gauge steel plate, which uniformly cools steel plate over its entire length and eliminates plate warping, that is, a method of conveying and cooling the top and bottom surfaces of steel plate in a high temperature state after hot rolling while constraining the high temperature rolled steel plate by a plurality of sets or top and bottom draining rolls, wherein cooling nozzles having a large number of nozzle openings and individually or simultaneously spraying the two fluids of air and water are used to cool the steel plate, the cooling method of steel plate characterized by giving a stable pattern by driving out air trying to invade the path of flow reaching the front end of the cooling apparatus when the water which is fed is low in amount or low in pressure.

Abstract: A cooling apparatus of thick-gauge steel plate having a plurality of pairs of constraining rolls, each comprising a top roll and bottom roll, constraining and conveying hot rolled thick-gauge steel plate and a plurality of spray nozzles spraying water on the top and bottom surfaces of the thick-gauge steel plate conveyed between the adjoining pairs of constraining rolls before and after each other in the conveyance direction, said cooling apparatus of thick-gauge steel plate characterized by arranging said plurality of spray nozzles so that: (i) the sum of the areas of the impact surfaces of the water sprays from the top surface side spray nozzles on the surface of the thick-gauge steel plate is in the range of 4 to 90% of the surface area of the steel plate between the roll outer circumferences at the closest distance between the pairs of constraining rolls and (ii) the sum of the areas of the impact surfaces of the water sprays from the bottom surface side spray nozzles on the surface of the thick-gauge ste

Abstract: The present invention relates to an apparatus for cooling hot steel plate applied for controlled cooling of hot steel plate, obtained by hot rolling, while processing it constrained by constraining rolls and obtaining a steel material excellent and uniform in shape characteristics and provides a method of arranging and setting spray nozzles enabling uniform cooling in a direction perpendicular to processing and provides a method of arranging and setting spray nozzles of a spray cooling apparatus using two or more types of nozzles differing in amounts of water and spray regions to obtain a broad range of adjustment of amounts of water, wherein the spray nozzles are arranged so that a value of an n power of the impact pressures of the cooling water sprayed from the spray on the cooling surface integrated in the processing direction between pairs of constraining rolls becomes within ?20% of the highest value in the direction perpendicular to processing, where, 0.05?n?0.