In the production and processing of steel, the differences between hot rolling and cold rolling

Both hot rolling and cold rolling are processes for forming steel plates or profiles, and they have a great influence on the structure and properties of steel.

The rolling of steel is mainly hot rolling, and cold rolling is usually only used for the production of small-sized steel and sheet steel with precision dimensions.

The steel delivered in the hot-rolled state has a certain degree of corrosion resistance due to the high temperature, so it can be stored in the open air. However, this layer of oxide scale also makes the hot-rolled steel surface rough, and the size fluctuates greatly. Therefore, the steel with smooth surface, accurate size and good mechanical properties is required to use hot-rolled semi-finished products or finished products as raw materials and then cold-rolled production.

The hot-rolled steel coil used for cold rolling is used as the raw material, and is subjected to pressure processing after pickling to remove the oxide scale. The finished product is a hard-rolled coil.

Generally, cold-rolled steels such as galvanized and color steel plates must be annealed, so they have better plasticity and elongation, and are widely used in industries such as automobiles, home appliances, and hardware. For end use, cold rolling deteriorates the stamping performance, and the product is suitable for simple deformed parts.