How to distinguish hot rolled coils from cold rolled steel coils

First of all, we need to know what hot-rolled coils are and what cold-rolled coils are.

1. Hot rolled steel coils
Hot-rolled coils are made from slabs (mainly continuous casting billets), which are heated and made into strips by rough rolling units and finishing rolling units. The hot steel strip coming out of the last rolling mill of finishing rolling is cooled to the set temperature by laminar flow, and is rolled into steel strip coils by the coiler. The cooled steel strip coils are then rolled into steel strip coils.
Because hot-rolled steel plate products have excellent properties such as high strength, good toughness, easy processing and shaping, and good weldability, they are widely used in manufacturing industries such as ships, automobiles, bridges, construction, machinery, and pressure vessels.
With the increasing maturity of new control technologies such as hot-rolled dimensional accuracy, plate shape, and surface quality, and the continuous emergence of new products, hot-rolled steel plates and strip products have become more and more widely used and have become more and more powerful in the market. competitiveness.

2. Cold rolled steel coils
Cold-rolled coils are made of hot-rolled coils as raw materials and rolled at room temperature and below the recrystallization temperature, including plates and coils. Among them, those delivered in sheets are called steel plates, also called box plates or flat plates; those that are very long and delivered in rolls are called steel strips, also called coiled plates.
Cold-rolled coils are widely used in automobile manufacturing, electrical products, rolling stock, aviation, precision instruments, food cans, etc. Since rolling at room temperature does not produce iron oxide scale, the cold plate has good surface quality and high dimensional accuracy. Coupled with annealing treatment, its mechanical properties and process performance are better than hot-rolled thin steel plates. In many fields, especially In the field of home appliance manufacturing, it has gradually been used to replace hot-rolled thin steel plates.