Is hot-rolled steel coil a steel plate

 　　Also known as cold drawing (cold rolling) and hot rolling

　　1. Hot rolling

　　The broken continuous casting plate or blooming plate is used as the raw material, which is heated by the step-by-step heating furnace, and then discharged into the roughing mill after high-pressure water dephosphorization. The roughing material is cut, tail, and then fed into the finishing mill for computer controlled rolling. After final rolling, it is cooled by laminar flow (computer controlled cooling rate) and coiled by the coiler to become straight coils. The head and tail of straight hair curls are often tongue shaped or fish tailed, with poor accuracy in thickness and width. There are often defects such as wave shaped, folded edges, and tower shaped edges. Its coil weight is relatively heavy, and the inner diameter of the steel coil is 760mm. (Usually used in the pipe manufacturing industry.) The straight coil is processed by cutting the head, tail, edge, and multiple straightening, leveling, and other finishing lines before being cut or recoiled, resulting in products such as hot-rolled steel plates, flat hot-rolled steel coils, and longitudinal cut strips. If the hot rolled finished coil is pickled to remove oxide skin and coated with oil, it becomes a hot rolled pickled plate coil

　　2. Cold rolling

　　Hot rolled steel coils are used as raw materials, and after acid washing to remove oxide scales, cold continuous rolling is carried out. The finished product is rolled hard coils. Due to the cold work hardening caused by continuous cold deformation, the strength and hardness of the rolled hard coils increase, the toughness and plasticity index decrease, and the stamping performance deteriorates. It can only be used for parts with simple deformation. Rolling hard coils can be used as raw materials for hot-dip galvanizing plants, as hot-dip galvanizing units are equipped with annealing lines. The weight of the rolled hard coil is generally 6-13.5 tons, and the inner diameter of the steel coil is 610mm. Generally, cold continuous rolling plates and coils should undergo continuous annealing (CAPL unit) or annealing treatment in a furnace to eliminate cold work hardening and rolling stress, and achieve the mechanical performance indicators specified in the standard. The surface quality, appearance, and dimensional accuracy of cold-rolled steel plates are superior to hot-rolled plates