Abstract:
The layout combines a caster (1) for endless thin slab which is then sheared (2) to finish-rolled coil length or lengths. The layout includes a roller-hearth furnace (3) to heat-treat the lengthed slabs followed by a descaler washer (5) and seven-stand roll train (7). A second descaler (6) is placed between first (F1) and second (F2) stands of the train which terminates in a cooling sector (8) and shear (9) to divide up the semi-endless rolled strip for coil winches (10). Strand guidance is adjustable or again the slab caster is followed by a primary stand to reduce slab thickness. An induction heater should be provided between stands (F1-F7).
Abstract:
The invention relates to a rolling mill for hot-working thin steel strips and other similar metallic materials; in particular, this rolling mill consists of a series of tandem arranged stands (2) which act simultaneously on a strip and among which there is at least one cooling device (3). The latter is designed to lower the temperature of the strip in a controlled manner so as to change the metallurgical phase of the associated rolled material in the space between one stand and the other. According to a preferred embodiment of the invention, the rolling mill is of the finishing type and the cooling device makes use of water with laminar-flow pipes.
Abstract:
The invention relates to a combined regulating system for producing defined product characteristics in the rolling of austentic, mixed austentic and ferritic and ferritic steel qualities, using a measuring method to determine the roll gap of a roll pair by detecting the absolute position of the work and back-up rolls on the side facing away from the roll gap by optical position measurement. The upper edge of the top roll or the lower edge of the bottom roll is detected relative to the absolute position of the rolls, in segments over the barrel length, by means of adjacent sensors situated along the roll. The measuring results are incorporated in a suitable regulating operation that influences the geometry of the roll gap and rolled stock using a model that takes into account the influences of the deflecting and roll adjusting systems, the deflection of the rolls, flattening between the rolls, flattening between the work roll and the rolled stock and the wear and thermal crowning of the rolls. In addition to the necessary absolute thickness, the regulating operation ensures that the necessary thickness profile and the flatness criteria are produced.
Abstract:
The invention relates to a method for producing strips of non-alloy and low-alloy steel with homogeneous structures and properties by continuous hot-rolling, by passing several times in the austenite zone and then in the ferrite zone, as well as by reeling. The invention is characterized in that the steel strip that was continuously cast and/or rough rolled in the austenite zone is rolled by passing twice or more in the austenite zone, at a starting temperature T>/=Ar3 +30 DEG C with a total strain of eh>/=30 %. After each pass, the rolled product is intensively cooled until completion of the ferrite conversion. The rolled product is then subjected to final rolling by passing several times through the ferrite zone, with a total strain of en>/=60 %, until a final thickness is obtained.
Abstract:
The invention concerns a method of producing hot-rolled steel strip from continuously cast semi-finished steel in operating steps which follow one another directly. According to the invention, when the liquid steel has been transformed into the semi-finished steel in a stationary process, the semi-finished steel is introduced directly into a continuous hot-rolling mill without previously being separated from the continuous casting machine. By applying specific parameters, continuous steel strip of any thickness is then produced directly using the primary heat at the final rolling temperatures conventional in industrial 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 Ar3 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 Tt and above 200 DEG C, where Tt is the temperature at which 75 % of the steel is converted into ferrite, and (vi) coiling said strip at a temperature above 500 DEG C. Advantages of simplicity of the method and the plant required for it are obtained.