Device and method for descaling a workpiece that is in motion in relation to the device in a movement direction. The device includes a rotor head rotatable about a rotational axis and inclined diagonally at an angle (Y) with respect to an orthogonal on a surface of the workpiece. The device includes jet nozzles attached to the rotor head which dispense a pressurized liquid onto the workpiece at an angle of attack (α) inclined to the workpiece surface. The nozzles are fixedly attached on the rotor head such that during rotation of the rotor head about its axis of rotation, the spraying direction of the liquid dispensed from the nozzles with respect to a projection in a plane parallel to the surface of the workpiece, is aligned opposing to and at a spraying angle (β) of approximately between 170 and 190 degrees to the movement direction of the workpiece.

A steel sheet has a composition containing, by mass %, C: 0.04% to 0.20%, Si: 0.6% to 1.5%, Mn: 1.0% to 3.0%, P: 0.10% or less, S: 0.030% or less, Al: 0.10% or less, N: 0.010% or less, one, two, or all of Ti, Nb, and V in an amount of 0.01% to 1.0% each, and the balance being Fe and inevitable impurities, a microstructure including, in terms of area ratio, 50% or more of ferrite, in which an average grain diameter at a position located 50 μm from a surface of the steel sheet in a thickness direction is 3000×(tensile strength TS (MPa)).sup.−0.85 μm or less, C precipitates having a grain diameter of less than 20 nm formed in steel is 0.010 mass % or more, and a amount of precipitated Fe is 0.03 mass % to 1.0 mass %, and a roughness Ra of 3.0 μm or less.

A steel sheet has a composition containing, by mass %, C: 0.04% to 0.20%, Si: 0.6% to 1.5%, Mn: 1.0% to 3.0%, P: 0.10% or less, S: 0.030% or less, Al: 0.10% or less, N: 0.010% or less, one, two, or all of Ti, Nb, and V in an amount of 0.01% to 1.0% each, and the balance being Fe and inevitable impurities, a microstructure including, in terms of area ratio, 50% or more of ferrite, in which an average grain diameter at a position located 50 μm from a surface of the steel sheet in a thickness direction is 3000×(tensile strength TS (MPa)).sup.−0.85 μm or less, C precipitates having a grain diameter of less than 20 nm formed in steel is 0.010 mass % or more, and a amount of precipitated Fe is 0.03 mass % to 1.0 mass %, and a roughness Ra of 3.0 μm or less.

A filter jet-director unit for a high-pressure nozzle for descaling metal products, having a housing, wherein the housing has an entry filter, a connector end for connecting to a nozzle, a flow duct between the entry filter and the connector end, and a jet director having flow-guiding faces in the flow duct. The flow-guiding faces of the jet director at least in portions are disposed in the region of the entry filter.

A device and a method for applying a liquid medium to a roll, and/or to a rolled material, a slab or a roughed strip and/or for removing the liquid medium, wherein the device has at least one spray nozzle, at least one row of spray nozzles or at least one cooling bar for spraying on the medium and at least one plate element, which is designed for collecting the medium. The roll is designed for rolling rolled material, wherein the rolled material, the slab or the roughed strip is conveyed in a conveying direction. In order to allow an improved cooling effect of a roll to be cooled or an improved removal of descaling water, the plate element has on one of its surfaces at least one directing element, which is designed for diverting medium into a transverse direction, which lies horizontally and transversely in relation to the conveying direction.

A descaling device having a device housing, a shaft, a shaft bearing, a nozzle head and a medium coupling, wherein the shaft bearing is arranged in the device housing and the shaft is mounted in the device housing by the shaft bearing for carrying out a rotary movement, wherein the shaft and the nozzle head are detachably connected to one another in a non-destructive manner, wherein the medium coupling has a medium connection for supply of a medium, wherein the shaft has a shaft cavity for conducting the medium supplied at the medium connection to the nozzle head. The descaling device has an improved maintainability, and reliability due to the descaling device having a motor, and due to the motor being arranged on the shaft in the device housing between the nozzle head and the medium coupling in order to generate the rotary movement of the shaft.

A descaling device having a device housing, a shaft, a shaft bearing, a nozzle head and a medium coupling, wherein the shaft bearing is arranged in the device housing and the shaft is mounted in the device housing by the shaft bearing for carrying out a rotary movement, wherein the shaft and the nozzle head are detachably connected to one another in a non-destructive manner, wherein the medium coupling has a medium connection for supply of a medium, wherein the shaft has a shaft cavity for conducting the medium supplied at the medium connection to the nozzle head. The descaling device has an improved maintainability, and reliability due to the descaling device having a motor, and due to the motor being arranged on the shaft in the device housing between the nozzle head and the medium coupling in order to generate the rotary movement of the shaft.

A press hardening steel by a thin slab casting and direct rolling has a tensile strength of 1500 MPa or more. The press hardening steel has a components by weight percent: C: 0.21-0.25%, Si: 0.26-0.30%, Mn: 1.0-1.3%, P≤0.01%, S≤0.005%, Als: 0.015-0.060%, Cr: 0.25-0.30%, Ti: 0.026-0.030% or Nb: 0.026-0.030% or V: 0.026-0.030%, or a mixture of two or more of the above in any proportion; B: 0.003-0.004%, and N≤0.005%. A method for producing the press hardening steel includes following steps: hot metal desulphurization; electric-furnace or converter smelting and refining; continuous casting; descaling, then entering a soaking furnace; heating and soaking; high-pressure water descaling, then entering a rolling mill; hot rolling; cooling; coiling; austenitizing; die deforming and quenching.

A press hardening steel by a thin slab casting and direct rolling has a tensile strength of 1500 MPa or more. The press hardening steel has a components by weight percent: C: 0.21-0.25%, Si: 0.26-0.30%, Mn: 1.0-1.3%, P≤0.01%, S≤0.005%, Als: 0.015-0.060%, Cr: 0.25-0.30%, Ti: 0.026-0.030% or Nb: 0.026-0.030% or V: 0.026-0.030%, or a mixture of two or more of the above in any proportion; B: 0.003-0.004%, and N≤0.005%. A method for producing the press hardening steel includes following steps: hot metal desulphurization; electric-furnace or converter smelting and refining; continuous casting; descaling, then entering a soaking furnace; heating and soaking; high-pressure water descaling, then entering a rolling mill; hot rolling; cooling; coiling; austenitizing; die deforming and quenching.

A descaling device having a device housing, a shaft, a shaft bearing, a nozzle head and a medium coupling, wherein the shaft bearing is arranged in the device housing and the shaft is mounted in the device housing by the shaft bearing for carrying out a rotary movement, wherein the shaft and the nozzle head are detachably connected to one another in a non-destructive manner, wherein the medium coupling has a medium connection for supply of a medium, wherein the shaft has a shaft cavity for conducting the medium supplied at the medium connection to the nozzle head. The descaling device has an improved maintainability and reliability due to the descaling device having a motor, and due to the motor being arranged on the shaft in the device housing between the nozzle head and the medium coupling in order to generate the rotary movement of the shaft.