Steel coil, a finished steel product such as sheet or strip which has been wound or coiled after rolling. In the light of experience gained during these years, ADTO classifies steel coils into hot and cold- rolled types, or stainless steel coil, carbon steel coil, and Galvanized steel coil according to current products and international standards.
The hot-rolled steel coil is produced from semi-finished products, which are reduced to certain thicknesses by rolling and annealing and wound into a roll. Hot-rolled steel is used for the manufacture of pipes, steel doors, and tanks or is further processed into cold-rolled steel.
Cold-rolled steel sheet in coil form is produced by removing rust from a hot-rolled sheet by "pickling" it in a weak acid solution, then washing, brushing, drying, oiling, and unrolling the sheet and finally performing cold-rolling by passing the sheet through a reducing mill under pressure and winding it into a roll. Cold-rolled steel is a more highly finished product and has a smoother surface, greater dimensional accuracy (thickness, width, length), and greater strength. Much cold-rolled steel is processed in the automotive industry, but some are also used in the manufacture of household goods.
Stainless steels are distinguished from carbon steel by their chromium content and, in certain cases - nickel. Adding chromium to carbon steel makes it more rust and stain-resistant, and when nickel is added to chromium stainless steel it enhances its mechanical properties, for example, its density, heat capacity, and strength. A stainless steel sheet is used, for example, in the manufacture of machinery, tools, and containers.
Carbon steel coil, a type of steel that generally has only a small quantity of elements other than carbon, silicon, manganese, sulfur, and phosphorus, so it has no significant alloying element. The carbon steel coil is good for second-grade applications placing no particular demands on surface quality. ADTO’s carbon coil steel comes in a variety of grades and thicknesses to support the countless applications of this metal. We offer carbon coil in hot-rolled, cold-rolled, galvanized, aluminized, and painted. Available grades include CS-B, FS -B, DS-B, DDS, EDDS, A36, SS Grades 30-55, A572-50 HSLA Grades 40-80, and A606.
Galvanized steel coil produced when hot or cold rolled sheet or strip is coated with zinc, either by the hot-dipping or electrolytic deposition processes. Zinc coating applied by the hot-dip method is normally heavy enough to resist corrosion without additional protective coating. Materials electronically galvanized are not used for corrosion-resistant applications without subsequent chemical treatment and painting, except in mildly corrosive conditions, due to the thin coating of zinc. Galvanize is a pure zinc coating. A special heat-treating process converts the pure zinc coating to a zinc/iron alloy coating, and the product is known as galvanneal. Galvanized sheet is used, e.g. in the automotive industry or in the production of roofing materials.