Cold-rolled steels are the product that is obtained from a hot-rolled coil to obtain a surface that is free of oxides and imperfections, through a tandem train process that can be continuous or in batch annealing. After this there is a tempering process to achieve the hardening and the final finish.
You can find these products in many applications, such as control panels and white good panels, industrial machinery, the automotive industry, piping and sheets for construction, metal drums and containers, etc.
Cold-rolled products are made at close to the ambient temperature, and are focussed on obtaining high surface quality and dimensional tolerances. The objective of the processes used in the cold rolling area is to obtain, from hot-rolled steel, thinner materials with mechanical properties and surface finishes that enable a broad range of industrial applications. Before it goes through the rolling mill, the sheet is subjected to a pickling process. The final dimensions of the sheet are obtained in the mill. The process is completed on the electrolytic cleaning, set-to, tempering, levelling and inspection lines. The steel sheet, during the hot-rolling processes, its transportation and storage, forms oxides on its surface, which are also called mill scale, which are removed through the pickling process. This surface oxidation can have negative consequences if it is not removed, such as a weakening of the metal surface and incrustations on the cold-rolled sheets and cylinders.