Process and relative production line for the direct manufacture of finished pressed or deep drawn pieces from ultrathin hot rolled strip cast and rolled in-line

A process for the manufacture of cold rolled and finished steel strip in gauges 0.5-0.1 mm and a maximum width of 2000 mm for the direct preparation of end products such as pressed and deep drawn pieces, which includes the following steps:

• casting for thin slabs with a thickness of the bar leaving the mould of 90-50 mm;
• bar thickness reduction during solidification to a minimum of 30 mm;
• slab thickness reduction directly after solidification connected to the casting process to a minimum of 6 mm (roughing stage), with a central symmetrical crown of 1.0-1.5%;
• temperature regulation and control of the cast-rolled slab directly after the roughing phase;
• production of a cast-rolled product controlled as regards temperature, thickness, width, crown and flatness;
• finishing rolling in order to obtain a recrystallized hot strip with a thickness of 1.2-0.6 mm and a crown of 1.0-1.5%;
• pickling process with subsequent cold rolling for the production of cold strip of a thickness between 0.5 and 0.1 mm;
• cold finishing (skinpass) preceded by temperature management for the control of the structure of the material;
• characterized by comprising the additional step of in-line pressing of finished, ready to be used pieces with the return of the processing scrap to the steel manufacturing cycle;
• wherein the intermediate strip is hot rolled directly in the finishing mill without intermediate winding through a coil-box and the hot strip is sent directly to pickling without intermediate winding in a downcoiler.