Patent classifications
B21B45/004
Cold rolling mill with alternative feed of a steel strip over two different paths
A first steel strip and a second steel strip (7) are rolled in succession in at least one roll stand (1) of a cold rolling mill. A rolling pause, in which no steel strip is rolled, is provided between the rolling of the first and the second steel strip (7). The first steel strip is fed over a first path starting from a first pay-off reel (2), and the second steel strip (7) is fed over a second path starting from the first pay-off reel (2), or from a second pay-off reel different from the first pay-off reel (2). The first steel strip is not heated as it is fed to the rolling mill (1), whereas, by contrast, the second steel strip (7) is heated. The second path is longer than the first path.
DETERMINATION OF AN ADJUSTMENT OF A ROLL STAND
Slabs pass through a furnace in a conveying direction, are heated to rolling temperature, and are rolled in at least one roller stand. Determining device receives information showing the regions occupied by the slabs relative to one another when passing through the furnace in at least one direction orthogonal to the conveying direction, and determines, for at least one rolling pass of the respective slab, an adjustment of the roller stand performing this rolling pass without prior determination of a respective temperature distribution of a respective slab or without utilization of a determined temperature of a respective slab. The determining device takes into account the region occupied by the respective preceding and/or following slab, seen in the conveying direction, relative to the respective slab, and supplies the respective determined adjustment of the roller stand to a control device, which controls the roller stand when the respective slab is being rolled.
Hot rolled steel sheet and method for producing same
A hot rolled steel sheet is provided, which is excellent in collision characteristics, excellent in anisotropy of toughness, and high in strength. The hot rolled steel sheet is characterized by containing, by mass %, C: 0.10% to 0.50%, Si: 0.10% to 3.00%, Mn: 0.5% to 3.0%, P: 0.100% or less, S: 0.010% or less, Al: 1.00% or less, N: 0.010% or less and a balance of Fe and impurities, wherein a metal structure at position of ¼ thickness from surface in L-cross-section of the steel sheet comprises prior austenite grains of average value of aspect ratios of 2.0 or less, average grain size of 0.1 μm to 3.0 μm, and coefficient of variation of a standard deviation of grain size distribution/average grain size of 0.40 or more, and a texture with X-ray diffraction intensity ratio of {001}<110>orientation for random samples of 2.0 or more, and the steel sheet has tensile strength of 1180 MPa or more.
DEVICE FOR THE INDUCTIVE HEATING OF A WORKPIECE IN A ROLLING MILL
A device (1) for inductive heating of a workpiece (2) in a rolling mill, the device (1) including: a converter (3) for creating an alternating voltage, a capacitor bank (6) electrically connected to the converter (3), and having a plurality of capacitors (7) connected in parallel, a working field (8), in which an upper coil (10) and a lower coil (11) are arranged. The workpiece (2) is able to be passed between the coils (10, 11) and is thereby inductively heated by cross-field heating. A housing (4) arranged next to, below or above the working field (8). The converter (3) and capacitor bank (6) are arranged in the housing (4). The coils (10, 11) are each electrically connected to the capacitor bank (6) by a flexible cable (12, 13). The cable (12, 13) is a coaxial cable (27), with one phase of the alternating voltage applied to an inner conductor (28) and the other phase of the alternating voltage applied to an outer conductor (29) of the coaxial cable (27). The cables (12, 13) are cooled by a fluid, such as air or water (21).
CASTING-ROLLING INSTALLATION AND METHOD FOR TREATING A WORKPIECE BY MEANS OF SUCH AN INSTALLATION
A casting-rolling installation (10) with at least one finishing train (12), having at least a last roll stand (14) and with a cooling device (16) arranged downstream of the finishing train (12). To achieve a metallurgically advantageous microstructure, at least one temperature adjusting element (18) is provided, for increasing or at least substantially keeping constant a temperature of an object, in particular a workpiece, in order to counteract cooling of the object or the workpiece, which temperature adjusting element is arranged after the last roll stand (14) and before the cooling device (16) and/or is arranged after the last roll stand (14) and after the cooling device (16).
DEVICE AND METHOD FOR MANUFACTURING METAL CLAD STRIPS CONTINUOUSLY
The device and method for manufacturing metal clad strip continuously provided by the present invention, combines casting, rolling and heat treatment used for the single material manufacture with the continuous and large-scale manufacture method for the clad strip, greatly improves the productivity of clad strip. The present invention can be used for manufacturing single-sided or double-sided clad strips with different thickness specifications, wherein the base layer material or the clad layer material can be selected in a wide range, including carbon steel, stainless steel, special alloy steel, titanium, copper and the like. In the present application, continuous casting and rolling clad strip is implemented, which decrease the energy consumption and costs.
HEATING SYSTEM FOR DRILL STEEL PIPE BILLET AND HEATING METHOD THEREOF
The present invention discloses a heating system for drill steel pipe billet, comprising a feedback device, a propulsion device, a positioning device, a heating device, a temperature measuring device and a conveying device. The distance d.sub.1 and d.sub.2 of three flamethrowers are controlled through the feedback device. The heating temperature of the flamethrowers is controlled by the oxygen distribution box and the gas distribution box. On the other hand, the present invention also provides a heating method for drill steel pipe billet, which adopts the rolling forming method of gradient flame heating, which realizes the control of the density of the rolled pieces, avoiding the internal defects of the drill steel caused by the same deformation of the traditional pipe billet after uniform heating, improving the quality of the drill steel, and prolonging the service life of the drill steel. The radial temperature of the drill steel pipe billet is accurately controlled through the feedback device. Flame heating with low cost is adopted. For drill steel pipe billets of different dimensions, only a set of flamethrowers corresponding to the dimensions needs to be designed, and other devices are universal components, which do not need to be replaced.
METHODS FOR HEATING STRIP PRODUCT
Systems and methods for reducing the thickness of a strip of an aluminum-based material are disclosed. The aluminum-based material is pre-heated before running the material through a warm rolling process. The systems include devices for pre-heating, which can include a heated payoff station or a dedicated pre-heating station that applies heated rolls or acts as a heated tunnel.
Method for manufacturing ring-rolled product
A method for manufacturing a ring-rolled product forms the ring-rolled product from a ring material by using a mandrel roll and a main roll. The mandrel roll and the main roll are configured so as to contact inner and outer circumferential surfaces of the ring material, respectively, and are configured so as to press the ring material in a radial direction thereof in a state in which the ring material is rotated in a circumferential direction thereof. The method includes a step of rolling the ring material that includes an operation of induction-heating the main roll by at least one induction heating element and rolling the ring material between the mandrel roll and the main roll, which is induction-heated.
Combined continuous casting and metal strip hot-rolling plant
A combined continuous casting and endless rolling plant for a metal strip, comprising—a continuous casting line (1) for casting a slab; —a first rolling mill (6) for roughing the slab and for obtaining a transfer bar; —a second rolling mill (11) for finishing the transfer bar and for obtaining a strip; —a third rolling mill (18), comprising at least two rolling stands (17), for further reducing the N thickness of the strip; —accumulation means (20) of the strip comprising at least one first reel (37, 37′) dimensioned to wind and unwind a coil weighing from 80 to 250 metric tons and/or up to 6 meters in diameter, named mega coil; —first cutting means (13), arranged between said third rolling mill (18) and said accumulation means (20), configured to cut the strip after the mega coil has been wound on the at least one first reel (37, 37′); —at least one second reel (48) for winding portions of strip, unwound from said accumulation means (20), up to a predetermined weight limit or coil diameter limit; —second cutting means (47), arranged between said accumulation means (20) and said at least one second reel (48), adapted to cut the strip whenever a portion of strip wound on the at least one second reel (48) reaches said predetermined weight limit or coil diameter limit.