Cold-rolled steel sheets

The main industries that consume cold-rolled steel sheets include construction, machine building, automotive, white goods and consumer goods.

In the construction sector, cold-rolled sheets are primarily used to produce steel structures, bent closed and open profiles, facade elements, doors, etc.

In transport machine building and manufacture of white goods, cold-rolled sheets are predominantly used to manufacture bodies and load-bearing elements of cars and vehicles. Cold-rolled sheets should have good formability and a surface suitable for the application of various coating materials.

These steel are also used to manufacture tableware, packing materials and houseware for various applications. Large consumers of coldrolled sheets include service metal centres, which render their services to different sectors, from construction to instrumentation engineering. Using high-precision automated equipment, these companies cut, bend, machine and drill goods and parts made from cold-rolled steel sheets.

The standards applied in different countries to set the requirements for coldrolled steel – such as EN 10130, EN 10268, EN 10209, ASTM A1008 / A1008M, DSTU 2834, GOST 16523, GOST 9045 and GOST 17066, among others – specify steel grades and size range, their application (profiling, cold forming, enamelling, general use, etc), mechanical properties, surface quality and other parameters.

Cold-rolled sheets according to European standards

The most frequently followed European standards for the production are EN 10130, EN 10268 and EN 10209.

EN 10130 is applied to made of the low-carbon DC01, DC03, DC04, DC05, DC06 and DC07 steel grades for cold forming without coating with a minimum width of 600 mm and a minimum thickness of 0.35 mm

Cold-rolled steel sheets manufactured in accordance with this standard are normally supplied skin-passed; however, upon agreement, the material can be supplied without skin-pass rolling. The same is true of oiling used for rust protection. EN 10130 sets forth the requirements for surface quality (А, B) and finishing (gloss b, semi-gloss g, matte m, rough r) along with other parameters of cold-rolled sheets. Acceptable size and shape tolerances should correspond to EN 10131.

EN 10268 relates to cold-rolled flat steel with a thickness of 3 mm or less and a high yield strength suitable for cold forming. The reference document applies to the following cold-rolled steel grades with different chemical composition and mechanical properties:

• B – heat treated steels (HC180B, HC220B, HC260B, HC300B), which demonstrate a certain increase in the reference yield strength after their heating to 170°С for 20 minutes

• LA – low-alloyed / micro-alloyed steels (HC260LA, HC300LA, HC340LA, HC380LA, HC420LA, HC460LA, HC500LA), which have one or several alloying elements in their composition, such as niobium, vanadium or titanium, to achieve the required yield strength

• Y – inclusion-free steels (HC180Y, HC220Y, HC260Y), whose composition is controlled to improve plastic deformation r and strain hardening n

• I – isotropic steel (HC220I, HC260I, HC300I) with minor parameter for plastic deformation r

Sheets are supplied only as skin-passed material. Normally, rolled steel comes oiled. In this case, a homogeneous layer of neutral non-drying clean oil is applied to both sides for rust protection to avoid corrosion during three months of normal packing, transportation, handling and storage. Oil should be removable by alkaline solutions or common solvents. Cold-rolled plates are supplied with surface quality А or B as per EN 10130, except for LA steel, which can only have А type surface quality. Cold-rolled plates can be further used for metal coating by submerging the material into a metal bath, using the electrolytic deposition method, and/or applying organic and other types of coating. If such coating is required, this should be indicated in the request or order. Size and shape tolerances for products rolled to a thickness of 600 mm or more correspond to those indicated in EN 10131, while tolerances for products rolled to a thickness of less than 600 mm correspond to EN 10140.

EN 10209 is used to manufacture from the DC01EK, DC04EK, DC06EK, DC03ED, DC04ED and DC06ED steel grades for vitreous enamelling of rolled steel with a width of 600 mm or more and a thickness of 3 mm or less. The standard specifies the key requirements for chemical composition, mechanical properties, surface quality and test methods for cold-rolled plstes. Size and shape tolerances for such cold-rolled steel are specified in ЕN 10131.
 

Cold-rolled coils according to Ukrainian and CIS standards

In Ukraine and the CIS, the main standards for include:

• DSTU 2834 and the similar GOST 16523 standard are applied to thingauge material made from high-quality and regular-quality carbon steel for general applications, which is produced with a width of 500 mm or more and a thickness of up to 3.9 mm inclusive. Based on their ultimate strength, steel grades are classified into the following strength groups: K260V, K270V, OK300V, K310V, K330V, K350V, OK360V, OK370V, K390V, OK400V, K490V. Based on surface finish, products are classified into group I (super ultra finish), II (ultra finish) and III (extra finish). Based on drawing capacity, steel products are classified into products for deep drawing and normal drawing. The range of these cold-rolled products should correspond to GOST 19904.

• GOST 9045 specifies the requirements for thin-gauge cold-rolled material made from low-carbon high-quality steel with a thickness of up to 3.9 mm for cold forming. Based on rated characteristics, products can have a category from 1 to 5, and based on surface finish quality, products are classified into type I (ultra finish), II (super finish) and III (extra finish). Based on their drawing capacity (rolled products with thickness up to 2 mm), steel products are classified into products for super ultra complex, ultra complex, complex and deep drawing. The range of these cold-rolled products should correspond to GOST 19904.

• GOST 17066 describes technical specifications for thin-gauge highstrength rolled steel with a thickness of 0.5-3.9 mm and a minimum width of 500 mm manufactured in sheets and coils. Rolled steel is produced with a strength of 295, 315, 345, 355, 390. Shape and size tolerances of cold-rolled steel should also correspond to GOST 19904.

Cold-rolled sheets can be produced using one of these two main methods:

• Cutting coils on special cutting machines or using combined cutting followed by straightening, packing and marking finished sheets.

• Processing hot-rolled sheets on non-reversing cold-rolling mills. In this case, hot-rolled coils cut to sheets are used as feedstock. These sheets are processed in pickling lines and then, while still cold, are deformed by rollers to obtain thinner cold-rolled sheets.

Buy cold-rolled sheets from the manufacturer

Metinvest produces cold-rolled sheets from carbon and low-alloy steels in accordance with the requirements of international standards. Cold-rolled sheets can be purchased through the Group’s global sales network of 38 sales offices in Europe, Asia, Africa and North America, as well as 16 metal service centres in Ukraine and authorised dealers.