Abstract:
A hot rolling installation should be constructed and able to be operated so that strips of materials, which can be shaped with different levels of difficulty and have a thickness of less than 1 mm, can be rolled. According to the invention, strip speeds of 15 m/sec should not be exceeded at the outlet of the last roll stand regardless of the material being used, and the hot-rolled strip should have austenitic structures. To this end, the invention provides that thin slab thicknesses of approximately 50 mm are used for easily shapeable material, that the first of seven stands is driven or executes only a smoothing pass, the slab is de-scaled in front of and behind the first stand, and that the second to seventh stand effects the reduction in thickness to less than 1 mm.
Abstract:
The invention relates to a process for the production of tailored blanks by the hot rolling of a strip and to an apparatus for the performance of said process. To obtain tailored blanks to be cut to length from the rolled strip, the hot strip is cooled or heated in portions, so that with a substantially constant rolling force the strip undergoes a differential decrease in thickness in the individual portions, which have been given a differential yield stress value by the differential temperature adjustment.
Abstract:
A method of controlling a continuous steel strip casting process based on customer-specified requirements includes a general purpose computer in which product specifications of steel product ordered by a customer is entered. The computer is configured to automatically map the product specifications to process parameters/set points for controlling the continuous steel strip casting process in a manner to produce the customer ordered product, and in one embodiment produces a process change report detailing such process parameters/set points for operator use in physically implementing such process parameters/set points in the strip casting process. Alternatively, the computer may provide the process parameters/set points directly to the strip casting process for automatic control thereof in producing the customer ordered steel product. The process of the present invention is capable of substantially reducing the time between a customer request for a steel product and delivery thereof over that of conventional steel manufacturing processes.
Abstract:
A method for the manufacture of a strip of formable steel comprises the steps of (i) forming liquid steel by continuous casting into a slab having a thickness of not more than 100 mm, (ii) rolling the slab in the austenitic region into an intermediate slab having a thickness in the range 5 to 20 mm, (iii) cooling the intermediate slab to below the Ar.sub.3 temperature, (iv) holding the intermediate slab in an enclosure for temperature homogenisation, (v) rolling the intermediate slab into strip, with at least one rolling pass applying a thickness reduction of more than 50%, at a temperature below T.sub.t and above 200.degree. C., wherein T.sub.t is the temperature at which 75% of the steel is converted into ferrite, and (vi) coiling said strip at a temperature above 500.degree. C. Advantages of simplicity of the method and the plant required for it are obtained.
Abstract:
A production plant for producing hot-rolled flat products includes a rolling train composed of a plurality of roll stands, a run-out table with devices for cooling the hot strip, and with subsequently arranged coiling machines for coiling the strip. At least the first roll stand of the rolling train is a reversing stand. At least one reeling furnace each is arranged in front of and following the reversing stand. A controllable cooling unit is provided between the reversing stand and the reeling furnace in front of the reversing stand.
Abstract:
Provided is a hot press-formed member having excellent crack propagation resistance and ductility. The hot press-formed member includes: a base steel sheet and a zinc or zinc alloy plating layer on at least one surface of the base steel sheet. The base steel sheet contains, by wt %, carbon (C): 0.08-0.30%, silicon (Si): 0.01-2.0%, manganese (Mn): 3.1-8.0%, aluminum (Al): 0.001-0.5%, phosphorus (P): 0.001-0.05%, sulfur (S): 0.0001-0.02%, nitrogen (N): 0.02% or less, and a balance of iron (Fe) and other impurities. The hot press-formed member comprises 1-30 area % of retained austenite as a microstructure, and a Mn(wt %)/Zn(wt %) content ratio in an oxide layer of 0.5-1.2 μm in a thickness direction from a surface layer of the plating layer is 0.1 or more.
Abstract:
A device for producing a thin steel strip, comprising at least one or more continuous-casting machines (1) for casting thin steel slabs, a furnace device (7) which is suitable for heating and/or homogenizing a slab, and at least one rolling device for reducing the thickness of a slab which is conveyed out of the furnace device (7), a welding machine being arranged between the continuous-casting machine (1) or continuous-casting machines (1) and the rolling device (10), for the purpose of joining slabs together.
Abstract:
A method of shaping a metal strip in a hot rolling installation including arranged one after another finishing train, cooling section, and coiler, with the method including providing, in a region between an end of the cooling section and the coiler, rolls for reducing a strip thickness, and reducing the thickness of the strip after the strip leaves the cooling section; and an installation for effecting the method.
Abstract:
A method for producing coated hot-rolled or cold-rolled products, particularly steel strip, and an apparatus for carrying out the method, wherein thin strip is cast especially by a travelling mold and the cast strip is guided on-line as a master strip into an inversion casting plant for strip coating, the surface of the coated strip is smoothed with rolls, and if necessary, the thickness of the coated and smoothed strip is reduced in a rolling process. The apparatus includes a strip casting plant, particularly with a travelling mold for producing a thin strip, an inversion casting plant arranged on-line following the strip casting plant for coating the thin strip or master strip from the strip casting plant, at least one pair of smoothing rolls arranged following the inversion casting plant for smoothing the surface of the coated strip emerging from the inversion casting plant, and, if necessary, a subsequently arranged rolling mill for a reducing deformation of the coated and smoothed strip to the strip thickness to be produced.
Abstract:
Rolling method for thin flat products, used in the production of flat rolled products with a final thickness in the range of 0.6-1.5 mm or more, up to 2.0-3.0 mm, in a plant suitable to work thicknesses of up to 25.4 mm, the method being applied to slabs with a thickness of between 50 and 90 mm if arriving directly from the continuous casting machine or on slabs with a greater thickness, of between 80 and 200-250 mm, if fed from a furnace to accumulate and heat the slabs (22), the method comprising at least a first heat treatment, a roughing or pre-finishing pass, a temperature equalisation treatment and a finishing pass in a finishing train (19) comprising at least three reduction passes, the finishing pass being followed by a step of cooling and coiling the flat finished product, the product at the outlet of the roughing or pre-finishing pass being in the austenitic state .gamma., the finishing pass taking place in the rolling line (10) at least partly in the ferritic step or in the austenitic step, as desired. Rolling line adopting the method as above, wherein the finishing train (19) cooperates with a system (24) to condition and adjust the temperature of the slab.