Abstract: The present cooling device includes: when cooling regions obtained by dividing an entire cooling region into a plurality of portions in a steel sheet conveyance direction and three or more portions in a width direction are set as divided cooling surfaces, a cooling water nozzle 23 and a switching device that switches between collision and non-collision of cooling water jetted from the cooling water nozzle 23 with the divided cooling surface, the cooling water nozzle 23 and the switching device provided for each of the divided cooling surfaces; and a control device that controls operation of the switching device based on a width-direction temperature distribution. The cooling water nozzle 23 has a jet axis P inclined with respect to a vertical line to the entire cooling region when viewed in the steel sheet conveyance direction, and the cooling water goes to the side opposite to the cooling water nozzle 23 in the width direction after colliding with the divided cooling surface.

Abstract: Provided is a cooling device, where a hot-finish-rolling mill includes a plurality of nozzles which spray cooling water toward one of or both of upper and lower surfaces of a hot-rolled steel sheet just after rolled by rolling stands, the nozzles are provided on the inside of the upper and lower guides or adjoining to the guides on a downstream side, and a nozzle spray distance changes depending on a position of the nozzle in a rolling direction, wherein a spray angle of the nozzle at a position whose nozzle spray distance is the largest is smaller than a spray angle of the nozzle at a position whose nozzle spray distance is the smallest, and the spray angle of the nozzle becomes the same or smaller as the nozzle spray distance becomes large.

Abstract: The present cooling device includes: when cooling regions obtained by dividing an entire cooling region into a plurality of portions in a steel sheet conveyance direction and three or more portions in a width direction are set as divided cooling surfaces, a cooling water nozzle 23 and a switching device that switches between collision and non-collision of cooling water jetted from the cooling water nozzle 23 with the divided cooling surface, the cooling water nozzle 23 and the switching device provided for each of the divided cooling surfaces; and a control device that controls operation of the switching device based on a width-direction temperature distribution. The cooling water nozzle 23 has a jet axis P inclined with respect to a vertical line to the entire cooling region when viewed in the steel sheet conveyance direction, and the cooling water goes to the side opposite to the cooling water nozzle 23 in the width direction after colliding with the divided cooling surface.

Abstract: A cooling device cooling an undersurface of a hot rolled steel sheet that is being transported on transport rolls after finish rolling of a hot rolling step includes: width divided cooling zones that are a plurality of cooling zones into which a whole cooling zone is divided in a sheet width direction; divided cooling sections that are a plurality of cooling zones into which each of the width divided cooling zones is divided in the rolling direction; a water nozzle spraying cooling water over each of undersurfaces of the divided cooling sections; a switching mechanism switching the cooling water between impinging and not impinging on the divided cooling sections; a width direction thermometer measuring a temperature distribution in the sheet width direction; and a controller controlling operation of the switching mechanism.

Abstract: According to the present invention, there is provided a cooling apparatus for a steel material in which one portion in a longitudinal direction of an elongated steel material (10) is heated while the steel material is fed in the longitudinal direction in a state where one end portion of the steel material is gripped, and the one end portion is moved in a two-dimensional or three-dimensional direction so as to form the steel material into a predetermined shape including a bent portion and thereafter to cool a heated portion including the bent portion. The cooling apparatus includes a first cooling apparatus (22) that ejects a first cooling medium to the heated portion, and a second cooling apparatus (23) that is disposed on a downstream side from the first cooling apparatus when viewed along a feeding direction of the steel material, and that ejects a second cooling medium to the heated portion.

Abstract: A cooling device cooling an undersurface of a hot rolled steel sheet that is being transported on transport rolls after finish rolling of a hot rolling step includes: width divided cooling zones that are a plurality of cooling zones into which a whole cooling zone is divided in a sheet width direction; divided cooling sections that are a plurality of cooling zones into which each of the width divided cooling zones is divided in the rolling direction; a water nozzle spraying cooling water over each of undersurfaces of the divided cooling sections; a switching mechanism switching the cooling water between impinging and not impinging on the divided cooling sections; a width direction thermometer measuring a temperature distribution in the sheet width direction; and a controller controlling operation of the switching mechanism.

Abstract: A plurality of water removing nozzles of a water removing apparatus comprise one or more of a single far water removing nozzle and a far water removing nozzle group. The single far water removing nozzle forms a far end water removal single area that does not include one end but includes the other end in the width direction of a steel sheet conveyance plane. The far water removing nozzle group forms the far end water removal single area and one or more inner water removal single areas that do not include either end in the width direction of the steel sheet conveyance plane, in such a manner that the far end water removal single area and the one or more inner water removal single areas are aligned in order from the one end side to the other end side while overlapping with each other in the width direction of the steel sheet conveyance plane and aligned in order from the upstream side to the downstream side without overlapping in the conveyance direction.

Abstract: A hot-rolled steel sheet is cooled by jetting cooling water from spray nozzles to a steel sheet conveyance region in a width direction of the steel sheet conveyance region. The steel sheet conveyance region is a region that the hot-rolled steel sheet occupies on conveyor rolls, a pair of spray nozzles is arranged on both lateral sides in the width direction of the steel sheet conveyance region, and a plurality of spray nozzle pairs are aligned in a conveyance direction of the hot-rolled steel sheet. In regard to a collision region of cooling water jetted from the spray nozzle at the steel sheet conveyance region, a far end in a jet direction is positioned at an end of the steel sheet conveyance region, and a near end is positioned on an inner side of the steel sheet conveyance region. In the spray nozzle pair, the near ends of two collision regions coincide in the width direction to form a meeting.

Abstract: Provided is a cooling device, where a hot-finish-rolling mill includes a plurality of nozzles which spray cooling water toward one of or both of upper and lower surfaces of a hot-rolled steel sheet just after rolled by rolling stands, the nozzles are provided on the inside of the upper and lower guides or adjoining to the guides on a downstream side, and a nozzle spray distance changes depending on a position of the nozzle in a rolling direction, wherein a spray angle of the nozzle at a position whose nozzle spray distance is the largest is smaller than a spray angle of the nozzle at a position whose nozzle spray distance is the smallest, and the spray angle of the nozzle becomes the same or smaller as the nozzle spray distance becomes large.

Abstract: A hot-rolled steel sheet is cooled by jetting cooling water from spray nozzles to a steel sheet conveyance region in a width direction of the steel sheet conveyance region. The steel sheet conveyance region is a region that the hot-rolled steel sheet occupies on conveyor rolls, a pair of spray nozzles is arranged on both lateral sides in the width direction of the steel sheet conveyance region, and a plurality of spray nozzle pairs are aligned in a conveyance direction of the hot-rolled steel sheet. In regard to a collision region of cooling water jetted from the spray nozzle at the steel sheet conveyance region, a far end in a jet direction is positioned at an end of the steel sheet conveyance region, and a near end is positioned on an inner side of the steel sheet conveyance region. In the spray nozzle pair, the near ends of two collision regions coincide in the width direction to form a meeting.

Abstract: According to the present invention, there is provided a cooling apparatus for a steel material in which one portion in a longitudinal direction of an elongated steel material (10) is heated while the steel material is fed in the longitudinal direction in a state where one end portion of the steel material is gripped, and the one end portion is moved in a two-dimensional or three-dimensional direction so as to form the steel material into a predetermined shape including a bent portion and thereafter to cool a heated portion including the bent portion. The cooling apparatus includes a first cooling apparatus (22) that ejects a first cooling medium to the heated portion, and a second cooling apparatus (23) that is disposed on a downstream side from the first cooling apparatus when viewed along a feeding direction of the steel material, and that ejects a second cooling medium to the heated portion.

Abstract: A plurality of water removing nozzles of a water removing apparatus comprise one or more of a single far water removing nozzle and a far water removing nozzle group. The single far water removing nozzle forms a far end water removal single area that does not include one end but includes the other end in the width direction of a steel sheet conveyance plane. The far water removing nozzle group forms the far end water removal single area and one or more inner water removal single areas that do not include either end in the width direction of the steel sheet conveyance plane, in such a manner that the far end water removal single area and the one or more inner water removal single areas are aligned in order from the one end side to the other end side while overlapping with each other in the width direction of the steel sheet conveyance plane and aligned in order from the upstream side to the downstream side without overlapping in the conveyance direction.

Abstract: A water-blocking apparatus for cooling water for a hot-rolled steel sheet according to the present invention, which blocks cooling water sprayed onto a hot-rolled steel sheet at a sprayed water density of higher than 4 m3/m2/min and equal to or less than 10 m3/m2/min when the hot-rolled steel sheet is cooled after finish rolling of a hot-rolling process, includes: a plurality of water-blocking nozzles which spray water-blocking water onto the hot-rolled steel sheet. Impact areas of the water-blocking water respectively sprayed from the water-blocking nozzles are continuously lined up in a straight line in a width direction of the hot-rolled steel sheet on a surface of the hot-rolled steel sheet and the adjacent impact areas partially overlap.

Abstract: A full cone spray nozzle comprising: a nozzle body (1) having a liquid inlet (3) at its upstream end and a spray orifice (4) at its downstream end; a vane structure (2) of an axial direction length (W) and diameter (D) arranged with its outer circumferential surface in contact with the inside of the nozzle body (1); has a plurality of channel grooves (6) of width (T) and depth (H) at the outer circumferential surface of the vane structure (2); an upstream side projecting part (8) of a length (U) in the axial direction of the nozzle body (1) at an upstream side of the vane structure (2); a downstream side projecting part (9) of a length (P) in the axial direction of the nozzle body (1) at a downstream side of the vane structure (2); and a swirl flow chamber (5) of an axial direction length (L) which is a space formed by an inside wall surface of the nozzle body (1), the vane structure (2) and the spray orifice (4), wherein 0.25?T/D?0.30, 0.25?H/D?0.30, and 1.5?L/W?3.5 are satisfied.

Abstract: A full cone spray nozzle comprising: a nozzle body (1) having a liquid inlet (3) at its upstream end and a spray orifice (4) at its downstream end; a vane structure (2) of an axial direction length (W) and diameter (D) arranged with its outer circumferential surface in contact with the inside of the nozzle body (1); has a plurality of channel grooves (6) of width (T) and depth (H) at the outer circumferential surface of the vane structure (2); an upstream side projecting part (8) of a length (U) in the axial direction of the nozzle body (1) at an upstream side of the vane structure (2); a downstream side projecting part (9) of a length (P) in the axial direction of the nozzle body (1) at a downstream side of the vane structure (2); and a swirl flow chamber (5) of an axial direction length (L) which is a space formed by an inside wall surface of the nozzle body (1), the vane structure (2) and the spray orifice (4), wherein 0.25?T/D?0.30, 0.25?H/D?0.30, and 1.5?L/W?3.5 are satisfied.

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 apparatus for hot rolling is installed on a downstream side of a finishing mill of a continuous hot rolling mill, and cools a steel sheet rolled by the finishing mill while being conveyed. The cooling apparatus includes first pinch rolls which, during an interval when the steel sheet fed out from a final stand of the finishing mill moves from a position of the final stand to a position where a surface temperature of the steel sheet reaches 850° C. or less, pinch the steel sheet while applying tension of 3.9 MPa or greater.

Abstract: A water-blocking apparatus for cooling water for a hot-rolled steel sheet according to the present invention, which blocks cooling water sprayed onto a hot-rolled steel sheet at a sprayed water density of higher than 4 m3/m2/min and equal to or less than 10 m3/m2/min when the hot-rolled steel sheet is cooled after finish rolling of a hot-rolling process, includes: a plurality of water-blocking nozzles which spray water-blocking water onto the hot-rolled steel sheet. Impact areas of the water-blocking water respectively sprayed from the water-blocking nozzles are continuously lined up in a straight line in a width direction of the hot-rolled steel sheet on a surface of the hot-rolled steel sheet and the adjacent impact areas partially overlap.

Abstract: The present invention provides a method of cooling a hot-rolled steel strip which has passed through a finishing rolling, including: cooling the hot-rolled steel strip from a first temperature of not lower than 600° C. and not higher than 650° C. to a second temperature of not higher than 450° C. with cooling water having the water amount density of not lower than 4 m3/m2/min and not higher than 10 m3/m2/min, wherein with respect to the area of the target surface, the area of a portion where a plurality of spray jets of the cooling water directly strikes on the target surface is at least 80%.

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.