Provided is a cold rolling method by which the occurrence of wrinkles during cold rolling can be prevented without having to modify a mill. A cold rolling method of rolling a steel sheet in multiple rolling passes using a cold mill, the method including when the steel sheet unit tension N.sub.1 during steady-state rolling exceeds the reference unit tension N.sub.0 in a specific rolling pass in which the target sheet thickness t.sub.0 on an exit side of the rolling pass is less than or equal to a reference sheet thickness, controlling the steel sheet unit tension N.sub.2 in an initial stage of rolling on an entry side of the specific rolling pass to be less than the reference unit tension N.sub.0 and less than the steel sheet unit tension N.sub.1 during the steady-state rolling, the reference unit tension N.sub.0 is calculated by the formula (1): N.sub.0=(150/9)t.sub.0+27.1.

Provided is a cold rolling method by which the occurrence of wrinkles during cold rolling can be prevented without having to modify a mill. A cold rolling method of rolling a steel sheet in multiple rolling passes using a cold mill, the method including when the steel sheet unit tension N.sub.1 during steady-state rolling exceeds the reference unit tension N.sub.0 in a specific rolling pass in which the target sheet thickness t.sub.0 on an exit side of the rolling pass is less than or equal to a reference sheet thickness, controlling the steel sheet unit tension N.sub.2 in an initial stage of rolling on an entry side of the specific rolling pass to be less than the reference unit tension N.sub.0 and less than the steel sheet unit tension N.sub.1 during the steady-state rolling, the reference unit tension N.sub.0 is calculated by the formula (1): N.sub.0=(150/9)t.sub.0+27.1.

A method for partial hardening of an austenitic steel by utilizing during cold deformation the TWIP (Twinning Induced Plasticity), TWIP/TRIP or TRIP (Transformation Induced Plasticity) hardening effect. Cold deformation is carried out by cold rolling at least one surface of the steel with forming degree () of 560% in order to achieve in the steel at least two consecutive areas with different mechanical values in thickness, yield strength (R.sub.p0.2), tensile strength (Rm) and elongation, having a ratio (r) between the ultimate load ratio (F) and the thickness ratio (t) of 1.0>r>2.0, and in which the areas are mechanically connected to each other by a transition area having a thickness that is variable from the thickness of the first area in the deformation direction to the thickness of the second area in the deformation direction.

A method of controlling a rolling mill production system for production of a coil-shaped end product from a slab, the production including processing the slab by sequentially arranged production units, the processing by the production units resulting in a respective strip-shaped product having physical data, the method including modeling, under consideration of the physical data, the processing of a testing product by a plurality of production units arranged downstream from a given production unit while taking into account the physical data. If the modelling shows that, under consideration of the physical data, one of the products resulting from processing by the downstream production units does not meet a predetermined quality criterion, the intended manufacture of the product is interrupted and a signal relating to the interrupting is outputted.

A method of controlling a rolling mill production system for production of a coil-shaped end product from a slab, the production including processing the slab by sequentially arranged production units, the processing by the production units resulting in a respective strip-shaped product having physical data, the method including modeling, under consideration of the physical data, the processing of a testing product by a plurality of production units arranged downstream from a given production unit while taking into account the physical data. If the modelling shows that, under consideration of the physical data, one of the products resulting from processing by the downstream production units does not meet a predetermined quality criterion, the intended manufacture of the product is interrupted and a signal relating to the interrupting is outputted.

Method for the production of flat metal products, in particular coils of strip, in endless and/or semi-endless mode, in which a metal product is continuously fed to a rolling mill consisting overall of at least 4 stands. The rolling stands are, in sequence, roughing stands, and finishing stands. It is provided to perform a flying gauge change of the metal product exiting from the rolling mill.

A method for producing a semifinished product with locally different material thicknesses may involve preparing a multilayer, metal material composite, which has a plurality of layers with different ductilities, and rolling the material composite in a method for flexible rolling through a rolling gap formed between two rollers. The rolling gap may be configured such that regions with different material thicknesses are formed. In some cases, the multilayer, metal material composite is rolled at room temperature. Further, the plurality of layers of the multilayer, metal material composite may include a first outer layer disposed on a first side of a middle layer and a second outer layer disposed on a second side of the middle layer, with the second side of the middle layer being opposite the first side.

A method for producing a semifinished product with locally different material thicknesses may involve preparing a multilayer, metal material composite, which has a plurality of layers with different ductilities, and rolling the material composite in a method for flexible rolling through a rolling gap formed between two rollers. The rolling gap may be configured such that regions with different material thicknesses are formed. In some cases, the multilayer, metal material composite is rolled at room temperature. Further, the plurality of layers of the multilayer, metal material composite may include a first outer layer disposed on a first side of a middle layer and a second outer layer disposed on a second side of the middle layer, with the second side of the middle layer being opposite the first side.

An evaluation device that determines, based on data acquired by an acquisition device, an error value (PF) relating to the flatness of a strip of a rolling material exiting a roll stand, and supplies the determined error values (PF) to a control device, which takes the error values (PF) into account when determining adjustment variables(S) for flatness control elements of the roll stand. The interaction of the acquisition device, the evaluation device, the control device and the roll stand results in a closed control loop working in real time. In order to determine the particular error value (PF) of the strip, the evaluation device performs a local frequency analysis of the data and determines the particular error value (PF) on the basis of the local frequency analysis.

An evaluation device that determines, based on data acquired by an acquisition device, an error value (PF) relating to the flatness of a strip of a rolling material exiting a roll stand, and supplies the determined error values (PF) to a control device, which takes the error values (PF) into account when determining adjustment variables(S) for flatness control elements of the roll stand. The interaction of the acquisition device, the evaluation device, the control device and the roll stand results in a closed control loop working in real time. In order to determine the particular error value (PF) of the strip, the evaluation device performs a local frequency analysis of the data and determines the particular error value (PF) on the basis of the local frequency analysis.