Cold-rolled steel coils are a type of metal products obtained by plastic deformation of hot-rolled steel in cold rolling lines. As a result of this process the products have more accurate dimensional tolerances, better surface quality and mechanical characteristics compared to hot-laminated coils. In addition, cold rolling makes it possible to obtain thinner coils that are not currently available for hot laminators (less than 0.8-1.0 mm).
Classification, range and properties of cold-rolled steel coils
The standards of the different countries as regards the technical requirements for cold-rolled steel products, such as EN 10130, EN 10268, EN 10209, ASTMA1008/A1008M, DSTU 2834, GOST 16523, GOST 9045, GOST 17066, etc., stipulate different types and sizes of these products, their application (profiling, cold forming, painting, general use, etc.), mechanical properties, surface quality and other parameters.
Standards for cold-laminated coils
One of the most common European standards for the production of cold-rolled steel is EN 10130, EN 10268 and EN 10209.
EN 10130 is used for the sale of low carbon cold rolled steel of types DC01, DC03, DC04, DC05, DC06, DC07 for cold pressure treatment, uncoated, with a laminated metal width of at least 600 mm and a minimum thickness of 0.35 mm.
Steel type | Supeficial aspect | No slippage | D | Rm | A80 | r90 | n90 | Chemical composition (casting analysis) | ||||
Mpa | Mpa | Min % | Min | Min | Max % | Max % | S max % | Mn max % | Ti max % | |||
DC01 | to | - | -/280 | 270/410 | 28 | - | - | 0.12 | 0.045 | 0.045 | 0.60 | - |
B | 3 months | |||||||||||
DC03 | to | 6 months | -/240 | 270/370 | 34 | 1.3 | - | 0.10 | 0.035 | 0.035 | 0.45 | - |
B | 6 months | |||||||||||
DC04 | to | 6 months | -/210 | 270/350 | 38 | 1.6 | 0.180 | 0.08 | 0.030 | 0.030 | 0.40 | - |
B | 6 months | |||||||||||
DC05 | to | 6 months | -/180 | 270/330 | 40 | 1.9 | 0.200 | 0.06 | 0.025 | 0.025 | 0.35 | - |
B | 6 months | |||||||||||
DC06 | to | limitless | -/170 | 270/330 | 41 | 2.1 | 0.220 | 0.02 | 0.020 | 0.020 | 0.25 | 0.3 |
B | limitless | |||||||||||
DC07 | to | limitless | -/150 | 250/310 | 44 | 2.5 | 0.230 | 0.01 | 0.020 | 0.020 | 0.20 | 0.2 |
B | limitless | |||||||||||
According to this standard cold rolled steel is normally supplied laminated "skin-pass", however, on request can be supplied laminated coils without "skin-pass". The same goes for oiling to provide protection against atmospheric corrosion. EN 10130 specifies the surface quality (A, B) and finish (bright b, semi-bright g, matte m, rough r) as well as other parameters of the finished product. Dimensional tolerances must correspond to EN 10131.
Demanded dimensions: Thickness, mm | 0,25-2,0 1000-1500 610+/-10, 508+/-10 |
Weight, t | 10-25 |
Types of steel demanded | DC01-DC03; DX51D-DX52D, S220GD-S550GD (on the chemical composition side) and others |
Order and delivery | Cold hardened, annealed |
Application of cold-rolled steel coils
The main consumers of cold-laminated coils are construction, machinery construction, the automotive industry, metal and organic-coated products and household appliances.
In the construction sector cold-rolled steel is mainly used to manufacture closed tubes and profiles, facade elements and steel structures. The main requirements to be met by cold-rolled products include minimum thickness tolerances and coil weight of up to 25 tons. High-strength, low-alloy steels are becoming more common as they can reduce metal intensity and increase the load capacity of steel structures.
Production of cold-rolled steel coils
The starting material from which cold-laminated coils start are hot-laminated coils. The steel coil is first subjected to an acid pickling process and washed on the continuous pickling lines to remove contaminants from the sheet metal surface.
The coils are then introduced into continuous and reverse cold rolling mills, where they undergo plastic deformation without preheating until the cross section of the product meets the order requirements. Thus, the external deformation force causes changes in the structure and therefore in the properties of steel, which is called cold plastic deformation hardening. It is the phenomenon by which a doutile metal becomes harder and stronger, but has less plasticity and viscosity, although these properties may differ along the cross-section of the coil. Therefore, once they leave the laminator, most cold-rolled coils go through heat treatment, annealing, hood furnaces or continuous lines.
In the final stage of production, cold-laminated and picked coils move to the winding lines, going through the skin pass and hardening process, longitudinal and transverse cutting lines, followed by inspection and packaging. Once the process is complete, the coils will be taken to the finished product warehouse.
Hot Tags: in 10130 cold rolled steel coil, supplier, customized, wholesale, cheap, discount, price list, low price, in stock, free sampler
