Hot-rolled steel coil is produced using slabs (primarily continuously cast slabs) as raw material; after being heated in a reheating furnace (or homogenized in a soaking pit), the material is rolled into steel strip by roughing and finishing mill trains.
Hot-rolled steel coil products generally comprise medium-to-thick wide steel strip, thin wide hot-rolled steel strip, and hot-rolled sheet. Medium-to-thick wide steel strip refers to steel strip with a thickness of ≥3 mm but <20 mm and a width of ≥600 mm, produced using equipment such as continuous wide-strip hot rolling mills or furnace-coil mills, and delivered in coil form. Thin wide hot-rolled steel strip refers to steel strip with a specific thickness (typically <3 mm) and a width of ≥600 mm, produced using equipment such as continuous wide-strip hot rolling mills, furnace-coil mills, or thin-slab continuous rolling lines, and delivered in coil form. Hot-rolled sheet refers to individual steel plates of a specific thickness.
Based on differences in material composition and mechanical properties, hot-rolled steel coils can be classified into ordinary carbon structural steel, low-alloy steel, and alloy steel. Based on their intended applications, they can be classified into steels for cold forming, structural steels, automotive structural steels, corrosion-resistant structural steels, steels for mechanical structures, steels for welded gas cylinders and pressure vessels, pipeline steels, and others.