Cold rolled steel in accordance with GOST: in simple terms, how to choose high-quality steel tape

In order not to be disappointed in the purchased material and make a product of the highest quality, you need to choose cold rolled strip, in accordance with GOST 21996-76. One of its main criteria is the high accuracy of geometric dimensions. This makes it possible to produce parts and structures that fully comply with technical specifications, as well as to use the material economically, minimizing the amount of waste.

In addition, cold-rolled metals have excellent mechanical properties properties, in particular, high strength, resistance to wear and corrosion. But let's look at what sheet material that meets the established state standard should look like.‍

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GOST 21996-76: what characteristics does it regulate

The first thing that GOST says is the classification and grade of metal. Cold-rolled strip is divided according to the following characteristics:

• Durability — may be of the first, second or third group. It is marked 1P, 2P and 3P, respectively. The indicators are temporary resistance or hardness (only one of these parameters is controlled).
• Edge view — can be processed (D) or cropped. In the first case, the edge must be blunt, in the second case, minimal burrs and irregularities are allowed.
• Production accuracy — normal, high and high. Moreover, it can be regulated both in width (PS and PS) and in thickness (PT and VT). GOST establishes acceptable dimensional deviations for each type of tape in accordance with its thickness and width.
• Surface type:
  light brown — must have a color from light to dark gray;
  pale yellow with an oxide film of iridescent colors — The colors can range from pale yellow to deep blue (marking — C);
  dark — can be of any color, as well as covered with an oxide film or a layer of lubricant (indicated by the letter H);
  colorized — can have any shade from dark blue to light yellow, including several in one roll at the same time (marking — K);
  polished — has a shiny surface (marked with the letter C).
  Overall dimensions — if the sheet is up to 40 mm wide, its thickness can start from 0.05 mm, with a width of 45 mm or more, the thickness must be at least 0.1 mm.

• Overall dimensions — if the sheet is up to 40 mm wide, its thickness can start from 0.05 mm, with a width of 45 mm or more, the thickness must be at least 0.1 mm.

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Technical requirements for cotton tape

GOST 21996 approves steel grades that can be used for cold rolling. As well as a number of technical characteristics that the finished product must meet. Including:

• Vickers hardness: for the first strength group — 375-485 N, for the second — 486-600 N, for the third — over 600 N;
• temporary resistance: for the first one — 130-160 kgf/mm², for the second — 161-190 kgf/mm², for the third — over 190 kgf/mm²;
• number of bends: the minimum allowable value depends not only on the strength class of the material, but also on the steel grade;
• tape surface quality: there must be no delamination, rust, sinks, scratches, roller prints and a number of other damages.

GOST 21996-76 also regulates the thickness and weight of cold-rolled strip coils, the rules for marking, packaging, transportation and storage, technical control standards for the acceptance of finished products and product testing methods.‍

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How to choose cold-rolled strip

Often, metallurgical enterprises produce cold rolled products not in accordance with GOST, but according to their own specifications (specifications). At the same time, visually, such material can fully comply with the established standard, but during operation it can present unexpected unpleasant surprises. If you strictly monitor the quality of your products in your production, we recommend that you read the technical documentation before buying cold-rolled metal, as well as check the metal's compliance with the declared characteristics (geometric dimensions, surface quality, mechanical properties).

Another option is to choose a reliable supplier that produces cold-rolled strip in accordance with GOST and can provide appropriate certificates. One of these is St. Petersburg Precision Alloy Plant. The company has the necessary production facilities and its own quality control laboratory with modern high-precision equipment. All this makes it possible to produce cold rolled products in full compliance with GOST 21996, as well as to produce custom-made products (with any tolerances and from any steel grade). If you would like to order x/k tape, give us a call or leave a request, we will get back to you as soon as possible.