Disclosed is a treatment line for the continuous treatment of metal strips having a dual purpose, i.e. for producing strips that are annealed and dip-coated with a metal alloy and for producing strips that are annealed and not coated, comprising a dual-purpose cooling tower, i.e. for cooling strips that are annealed and not coated in a non-oxidizing atmosphere and for air-cooling strips that are annealed and coated.

A continuous induction heat treating apparatus is provided including a conveyor path defining an axis for a workpiece to be conveyed through the apparatus. The apparatus includes an induction heating station positioned along the conveyor path and operable to induce heating in the workpiece as the workpiece is conveyed through the induction heating station. A quenching station is positioned in a downstream direction from the induction heating station. The quenching station is coupled to a water supply and includes a plurality of sprayers in fluid communication with the water supply and operable to spray water toward the axis for quenching the workpiece as the workpiece is conveyed through the quenching station. The apparatus further includes a quench adjustment mechanism including an actuator coupled to at least a first one of the plurality of sprayers for re-positioning a point of intersection defined between the first sprayer and the axis.

A high-strength galvanized steel sheet includes a steel sheet having a steel composition having a specific component composition, a steel structure containing martensite and bainite at more than or equal to 70% (including 100%), ferrite at less than 20% (including 0%), and retained austenite at less than 5% (including 0%) in terms of area ratio, the amount of diffusible hydrogen in steel being less than or equal to 0.20 mass ppm; and a galvanizing layer provided on a surface of the steel sheet, having a content amount of Fe of 8 to 15% in mass %, and having an coating weight per one surface of 20 to 120 g/m.sup.2, wherein the amount of Mn oxides contained in the galvanizing layer is less than or equal to 0.050 g/m.sup.2, and a tensile strength is more than or equal to 1100 MPa and a yield ratio is more than or equal to 0.85.

A high-strength galvanized steel sheet includes a steel sheet having a steel composition having a specific component composition, a steel structure containing martensite and bainite at more than or equal to 70% (including 100%), ferrite at less than 20% (including 0%), and retained austenite at less than 5% (including 0%) in terms of area ratio, the amount of diffusible hydrogen in steel being less than or equal to 0.20 mass ppm; and a galvanizing layer provided on a surface of the steel sheet, having a content amount of Fe of 8 to 15% in mass %, and having an coating weight per one surface of 20 to 120 g/m.sup.2, wherein the amount of Mn oxides contained in the galvanizing layer is less than or equal to 0.050 g/m.sup.2, and a tensile strength is more than or equal to 1100 MPa and a yield ratio is more than or equal to 0.85.

The controlled cooling of previously heated and substantially straight steel wires of diameter more than 3.5 mm to a predetermined temperature including the steps: guiding the wires along individual paths through first coolant bath having bath liquid of water and a stabilizing additive, the bath liquid and the wires create a steam film around each wire along individual paths; directing an impinging liquid immersed inside first coolant bath towards the wires over a length along individual paths to cool down the wires, the impinging liquid decreases the thickness of the steam film or destabilizes the steam film, increasing speed of cooling over the length along individual paths; guiding the wires along individual paths out of the first coolant bath to be cooled down in air; after the further cooling, guiding the wires along individual paths through second coolant bath.

The controlled cooling of previously heated and substantially straight steel wires of diameter more than 3.5 mm to a predetermined temperature including the steps: guiding the wires along individual paths through first coolant bath having bath liquid of water and a stabilizing additive, the bath liquid and the wires create a steam film around each wire along individual paths; directing an impinging liquid immersed inside first coolant bath towards the wires over a length along individual paths to cool down the wires, the impinging liquid decreases the thickness of the steam film or destabilizes the steam film, increasing speed of cooling over the length along individual paths; guiding the wires along individual paths out of the first coolant bath to be cooled down in air; after the further cooling, guiding the wires along individual paths through second coolant bath.

A cooling device for a metal plate includes a plurality of first nozzles and a plurality of second nozzles disposed on both sides of the metal plate, respectively, in a thickness direction of the metal plate across a pass line of the metal plate. The plurality of first nozzles form a staggered array in which a pitch in a width direction of the metal plate is Xn, a pitch in a longitudinal direction of the metal plate is Yn, and an offset amount in the width direction of a pair of first nozzles disposed adjacent to each other in the longitudinal direction is ΔXn. The plurality of second nozzles form a staggered array in which a pitch in the width direction is Xn, a pitch in the longitudinal direction is Yn, and an offset amount in the width direction of a pair of second nozzles disposed adjacent to each other in the longitudinal direction is ΔXn. The staggered array of the first nozzles and the staggered array of the second nozzles are disposed offset from each other such that, a center of the second nozzle is at a position offset by a shift amount S from a center of the first nozzle in the width direction, and the center of the second nozzle is positioned in a region defined by an oval having a semi-axis of ΔXn/4 in the width direction and a semi-axis of Yn/3 in the longitudinal direction. The shift amount S is expressed by S=m×ΔXn/2, where m is an odd number such that S is closest to Xn/2.

A cooling device for a metal plate includes a plurality of first nozzles and a plurality of second nozzles disposed on both sides of the metal plate, respectively, in a thickness direction of the metal plate across a pass line of the metal plate. The plurality of first nozzles form a staggered array in which a pitch in a width direction of the metal plate is Xn, a pitch in a longitudinal direction of the metal plate is Yn, and an offset amount in the width direction of a pair of first nozzles disposed adjacent to each other in the longitudinal direction is ΔXn. The plurality of second nozzles form a staggered array in which a pitch in the width direction is Xn, a pitch in the longitudinal direction is Yn, and an offset amount in the width direction of a pair of second nozzles disposed adjacent to each other in the longitudinal direction is ΔXn. The staggered array of the first nozzles and the staggered array of the second nozzles are disposed offset from each other such that, a center of the second nozzle is at a position offset by a shift amount S from a center of the first nozzle in the width direction, and the center of the second nozzle is positioned in a region defined by an oval having a semi-axis of ΔXn/4 in the width direction and a semi-axis of Yn/3 in the longitudinal direction. The shift amount S is expressed by S=m×ΔXn/2, where m is an odd number such that S is closest to Xn/2.

A nozzle system for a band floating system for floatingly guiding a band-shaped material having a nozzle body having a front edge area and a rear edge area opposite to the front edge area, a front gas nozzle arrangement arranged at the front edge area, a rear gas nozzle arrangement arranged at the rear edge area, and a nozzle arrangement arranged, in the conveying direction, in front of the front gas nozzle arrangement and/or behind the rear gas nozzle arrangement such that a liquid fluid is flowable in a fluid jet into a nozzle floating field in the direction towards a band running plane for temperature-controlling the band-shaped material.

A cooling roll including an axle and a sleeve, the sleeve having a length and a diameter and being structured as follows: an inner cylinder, a plurality of magnets disposed along at least a portion of the inner cylinder length, each magnet being defined by a width, a height and a length, a cooling system surrounding at least a portion of the plurality of magnets, the cooling system and the plurality of magnets being separated by a gap defined by a height, the gap height being the smallest distance between a magnet and the cooling system above, the magnets having a width such that the following formula is satisfied: gap height x 1.1 magnet width gap height×8.6.