Abstract: A control device 20 obtains second pressing forces acting on work-side and drive-side roll chocks 112A and 112B on the basis of entry side and exit side first pressing forces, and controls at least one of work roll position control devices 140B and 141B and at least one of work roll pressing devices 130B and 131B changing a position of at least one of the roll chocks 112A and 112B in such a manner that a difference between the work-side second pressing force and the drive-side second pressing force is equal to or smaller than a predetermined value.

Abstract: Provided are: an upper work roll, radial bearings and a thrust bearing provided on a work side and a drive side of the upper work roll and supporting the upper work roll. Shift cylinders are provided on the work side of the upper work roll and apply forces in both a work side direction and a drive side direction to the thrust bearing. Shift cylinders are also provided on the drive side of the upper work roll and apply forces in both the work side direction and the drive side direction to the radial bearing 790B. The shift cylinders each apply a force in the same direction to the radial bearing and the thrust bearing when the upper work roll does not shift in an axial direction at least during rolling.

Abstract: A six-high rolling (also known as sexto) mill stand that is suited for hot rolling an intermediate strip into a thin strip that is less than 0.8 mm thick. A combined casting and rolling installation that includes the six-high rolling mill stand allowing for hot rolling in long uninterrupted sequences, without any change of the work rolls to obtain a strip with good geometry due to moderate rolling forces.

Abstract: Work roll balance force setting method of rolling mill. Determine kiss roll load Pk, rolling load Pr, and rolling torque Tr of work rolls relative to work roll angle ?x of tip position of rolled material between start and completion of biting of rolled material using mill longitudinal rigidity coefficient K and rolling condition. Determine traction coefficient ?rt between work and intermediate rolls, and maximum value ?rtmax of ?rt in relation to ?x when hypothetical work roll balance force Pb is applied from sum P of Pk, Pr, and Pb, and Tr between start and completion of biting. Compare tolerated value ?rter of ?rt with ?rtmax. Work roll balance force at start of biting reset to equal to or larger than required when ?rt assumes maximum value ?rtmax, and equal to or smaller than limit based on strength of rolling mill, when ?rter is equal to or larger than ?rtmax.

Abstract: A control device of a rolling mill includes first and second angle instruction sections that issue a first instruction to adjust an angle between an upper side pair and a lower side pair in a state in which the upper side pair has a parallel state and in a state in which the lower side pair has a parallel state; and a second instruction to tilt work rolls in a state in which an angle between backup rolls is maintained. An axial position instruction is issued to move the work rolls in a direction in which total thrust force received, by the work rolls tilted by the second instruction, from the backup rolls and a rolled material acts. The work roll pressing devices, work roll fixed position controlling devices, and shift cylinders are controlled on the basis of the first and second instructions, and the axial position instruction.

Abstract: A six-high rolling (also known as sexto) mill stand that is suited for hot rolling an intermediate strip into a thin strip that is less than 0.8 mm thick. A combined casting and rolling installation that includes the six-high rolling mill stand allowing for hot rolling in long uninterrupted sequences, without any change of the work rolls to obtain a strip with good geometry due to moderate rolling forces.

Abstract: A control device 20 obtains second pressing forces acting on work-side and drive-side roll chocks 112A and 112B on the basis of entry side and exit side first pressing forces, and controls at least one of work roll position control devices 140B and 141B and at least one of work roll pressing devices 130B and 131B changing a position of at least one of the roll chocks 112A and 112B in such a manner that a difference between the work-side second pressing force and the drive-side second pressing force is equal to or smaller than a predetermined value.

Abstract: Angles of an upper-side pair of an upper work roll 110A and an upper backup roll 120A, and a lower-side pair of a lower work roll 110B and a lower backup roll 120B are adjusted in a state where the upper-side pair is kept parallel and in a state where the lower-side pair is kept parallel. Thereafter, work-roll pressing apparatuses 130A and 130B, work-roll position control apparatuses 140A and 140B, backup-roll pressing apparatuses 150A and 150B, and backup-roll position control apparatuses 160A and 160B are controlled such that the angles of the upper work roll 110A and the lower work roll 110B are adjusted in a state where the angles of the upper backup roll 120A and the lower backup roll 120B are maintained.

Abstract: Provided are: an upper work roll, radial bearings and a thrust bearing provided on a work side and a drive side of the upper work roll and supporting the upper work roll. Shift cylinders are provided on the work side of the upper work roll and apply forces in both a work side direction and a drive side direction to the thrust bearing. Shift cylinders are also provided on the drive side of the upper work roll and apply forces in both the work side direction and the drive side direction to the radial bearing 790B. The shift cylinders each apply a force in the same direction to the radial bearing and the thrust bearing when the upper work roll does not shift in an axial direction at least during rolling.

Abstract: A hot rolling mill 1 includes a control apparatus 20 that adjusts an angle formed between an upper-side pair of an upper backup roll 120A and an upper work roll 110A and a lower-side pair of a lower backup roll 120B and a lower work roll 110B in a state where the upper-side pair is kept parallel and in a state where the lower-side pair is kept parallel. The hot rolling mill 1 is configured such that the work rolls 110A and 110B satisfy the condition that DW/Lb is equal to or smaller than 0.30 where DW is a diameter of the work rolls 110A and 110B, and Lb is the maximum strip width of a rolled material, and the hot rolling mill 1 performs rolling in a state where a bending force is applied to the work rolls.

Abstract: Provided is a nozzle header which sprays pressurized water to a high-temperature object, capable of inhibiting a member provided to spray nozzles from being deformed or damaged by heat at the time of operation, caused by radiation heat from the high-temperature object. The nozzle header for spraying water to a targeted object includes a header which supplies pressurized water, one or more of spray nozzles which spray the pressurized water supplied from the header, and a heat removal structure attached so as to be in contact with at least one of the spray nozzles, wherein the heat removal structure includes a coolant passage through which a cooling medium for cooling the heat removal structure itself and the spray nozzles passes.

Abstract: Provided is a cooling apparatus discharging water smoothly corresponding to increase of volume density of cooling water securing a high cooling capability. The apparatus disposed on downstream side from a row of hot finish rolling mill, supplying cooling water from above toward a pass line, includes a plurality of cooling nozzles arranged parallel in a pass line direction, and an upper surface guide disposed between the pass line and the cooling nozzles, wherein a predetermined relation is satisfied when defining: a volume density of cooling water sprayed as qm(m3/(m2·sec)); a pitch of the cooling nozzle in the pass line direction as L(m); a distance between a lower surface of the upper surface guide and the pass line as hp(m); a uniform cooling width as Wu(m); and a cross-sectional area of virtual flow path of discharging water flowing in a width direction of steel sheet as S(m2).

Abstract: Provided is a nozzle header which sprays pressurized water to a high-temperature object, capable of inhibiting a member provided to spray nozzles from being deformed or damaged by heat at the time of operation, caused by radiation heat from the high-temperature object. The nozzle header for spraying water to a targeted object includes a header which supplies pressurized water, one or more of spray nozzles which spray the pressurized water supplied from the header, and a heat removal structure attached so as to be in contact with at least one of the spray nozzles, wherein the heat removal structure includes a coolant passage through which a cooling medium for cooling the heat removal structure itself and the spray nozzles passes.

Abstract: In order to provide a manufacturing device and a manufacturing method for a hot-rolled steel strip, which are capable of obtaining the desired quality of material by rapid uniform cooling immediately after rolling, and improving yield by early sheet tension and sheet shape measurements, a manufacturing device for a hot-rolled steel strip is provided with a finishing rolling mill line (11), a first cooling unit (13) installed just behind the exit side of the finishing rolling mill line, and a pinch roll (14) which is installed on the exit side of the first cooling unit and in contact with both the upper and lower surfaces of a strip (S), at least a wiping roll (15) located on the upper side of the strip (S) is disposed between the first cooling unit and the pinch roll, and a tension/shape measuring unit (16) for measuring the tension and shape of the strip (S); is installed between the wiping roll and the pinch roll.

Abstract: Provided is a method of controlling operation of a tandem rolling mill which enables large reduction rolling in the latter-stage stand of the tandem rolling mill necessary for manufacturing fine-grained steel, and so on. The method comprises: a step of determining a first exit-side sheet thickness in rolling a constant portion of a material to be rolled; and a step of determining a second exit-side sheet thickness in rolling a front end portion of the material, such that a pre-tightening load becomes a set value or less; the material is rolled into the second exit-side sheet thickness, until the front end portion is fed into the stands; the constant portion is rolled by the stand given a pre-tightening load into the first exit-side sheet thickness; and the second exit-side sheet thicknesses of the stands given the pre-tightening load are made larger than the first exit-side sheet thickness.

Abstract: Provided is a cooling apparatus discharging water smoothly corresponding to increase of volume density of cooling water securing a high cooling capability. The apparatus disposed on downstream side from a row of hot finish rolling mill, supplying cooling water from above toward a pass line, includes a plurality of cooling nozzles arranged parallel in a pass line direction, and an upper surface guide disposed between the pass line and the cooling nozzles, wherein a predetermined relation is satisfied when defining: a volume density of cooling water sprayed as qm(m3/(m2·sec)); a pitch of the cooling nozzle in the pass line direction as L(m); a distance between a lower surface of the upper surface guide and the pass line as hp(m); a uniform cooling width as Wu(m); and a cross-sectional area of virtual flow path of discharging water flowing in a width direction of steel sheet as S(m2).

Abstract: An endless hot rolling material shear-joining method capable of threading hot rolling materials in a finish rolling process without strip breakage by controlling joining conditions for the hot rolling materials in an endless hot rolling process for high carbon steel, and an endless hot rolling plant therefor are disclosed. The shear-joining method for endless hot rolling materials of high carbon steel includes shear-joining high carbon steel metal bars comprising, in terms of weight %, 0.30% to 1.20% C, inevitable impurities, and balance Fe, or comprising 0.15% to 1.5% C containing at least one of Cr, Ni, Mo, V, Ti, W, B, Nb, and Sb, inevitable impurities, and balance Fe, such that a joined surface of the joined metal bars is formed to be inclined in a thickness direction of the metal bars, in a hot rolling plant by a joiner adapted to join the metal bars after overlapping tail part of a leading one of the metal bar and top part of a trailing metal bar.

Abstract: In order to provide a manufacturing device and a manufacturing method for a hot-rolled steel strip, which are capable of obtaining the desired quality of material by rapid uniform cooling immediately after rolling, and improving yield by early sheet tension and sheet shape measurements, a manufacturing device for a hot-rolled steel strip is provided with a finishing rolling mill line (11), a first cooling unit (13) installed just behind the exit side of the finishing rolling mill line, and a pinch roll (14) which is installed on the exit side of the first cooling unit and in contact with both the upper and lower surfaces of a strip (S), at least a wiping roll (15) located on the upper side of the strip (S) is disposed between the first cooling unit and the pinch roll, and a tension/shape measuring unit (16) for measuring the tension and shape of the strip (S); is installed between the wiping roll and the pinch roll.

Abstract: Provided is a method of controlling operation of a tandem rolling mill which enables large reduction rolling in the latter-stage stand of the tandem rolling mill necessary for manufacturing fine-grained steel, and so on. The method comprises: a step of determining a first exit-side sheet thickness in rolling a constant portion of a material to be rolled; and a step of determining a second exit-side sheet thickness in rolling a front end portion of the material, such that a pre-tightening load becomes a set value or less; the material is rolled into the second exit-side sheet thickness, until the front end portion is fed into the stands; the constant portion is rolled by the stand given a pre-tightening load into the first exit-side sheet thickness; and the second exit-side sheet thicknesses of the stands given the pre-tightening load are made larger than the first exit-side sheet thickness.

Abstract: An endless hot rolling material shear-joining method capable of threading hot rolling materials in a finish rolling process without strip breakage by controlling joining conditions for the hot rolling materials in an endless hot rolling process for high carbon steel, and an endless hot rolling plant therefor are disclosed. The shear-joining method for endless hot rolling materials of high carbon steel includes shear-joining high carbon steel metal bars comprising, in terms of weight %, 0.30% to 1.20% C, inevitable impurities, and balance Fe, or comprising 0.15% to 1.5% C containing at least one of Cr, Ni, Mo, V, Ti, W, B, Nb, and Sb, inevitable impurities, and balance Fe, such that a joined surface of the joined metal bars is formed to be inclined in a thickness direction of the metal bars, in a hot rolling plant by a joiner adapted to join the metal bars after overlapping tail part of a leading one of the metal bar and top part of a trailing metal bar.