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GOST 27772-2015

GOST 27772−2015 products for the construction of steel structures. General specifications


GOST 27772−2015

Group B20

INTERSTATE STANDARD

ROLLED PRODUCTS FOR STRUCTURAL STEEL CONSTRUCTIONS

General specifications

Rolled products for structural steel constructions. General specifications

ISS 77.140.50
77.140.70

Date of introduction 2016−09−01

Preface

Goals, basic principles and main procedure of works on interstate standardization have been established in GOST 1.0−2015 «interstate standardization system. Basic provisions» and GOST 1.2−2015 «interstate standardization system. Interstate standards, rules and recommendations on interstate standardization. Rules of development, adoption, renewal and cancellation"

Data on standard

1 DEVELOPED by the State enterprise „Ukrainian research & technology center of metallurgy industry „Energostal“ (SE „ukrrtc „Energostal“), the Interstate technical Committee for standardization MTK 327 „bars, shapes and sections“, Central research Institute of building constructions named.In.Kucherenko (tsniisk im.In.Kucherenko)

2 INTRODUCED by the Ministry of economic development and trade of Ukraine

3 ACCEPTED by the Interstate Council for standardization, Metrology and certification (minutes of August 27, 2015 N 79-P)

The adoption voted:

Short name of the country on MK (ISO 3166) 004−97 Country code MK (ISO 3166) 004−97 Abbreviated name of the national authority for standardization
Belarus BY Gosstandart Of The Republic Of Belarus
Kazakhstan KZ Gosstandart Of The Republic Of Kazakhstan
Kyrgyzstan KG Kyrgyzstandard
Russia EN Rosstandart
Tajikistan TJ Tajikstandart
Ukraine UA The Ministry Of Economic Development Of Ukraine

4 by Order of the Federal Agency for technical regulation and Metrology of April 7, 2016 N 247-St inter-state standard GOST 27772−2015 introduced as a national standard of the Russian Federation from September 1, 2016.

5 TO REPLACE GOST 27772−88


Information about the changes to this standard is published in the annual reference index „National standards“, and the text changes and amendments — in monthly information index „National standards“. In case of revision (replacement) or cancellation of this standard a notification will be published in the monthly information index „National standards“. Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet

1 Scope


This standard applies to hot-rolled sheet, universal broadband, shaped rolled and cold-formed sections, manufactured from hot rolled flats (hereinafter — products), intended for building steel structures with welded and other connections.

Rolled and formed sections, manufactured according to the present standard, can have a different purpose.

2 Normative references


This standard uses the regulatory references to the following standards:

GOST 82−70 hot-rolled steel universal broadband. Assortment

GOST 535−2005 the bar and shaped sections of quality carbon steel. General specifications

GOST 1497−84 (ISO 6892−84) Metals. Test methods tensile

GOST 7268−82 Steel. The method of determining the propensity to mechanical aging test the impact strength

GOST 7511−73 steel sections for window and lantern transoms and window panels of industrial buildings. Specifications

GOST 7564−97 hire. General rules of sample, blanks collection for mechanical and technological tests

GOST 7565−81 (ISO 377−2-89) Iron, steel and alloys. Sampling method for determination of chemical composition

GOST 7566−94 metal Products. Acceptance, marking, packing, transportation and storage

GOST 8239−89 hot-rolled steel I-Beams. Assortment

GOST 8240−97 Channels hot-rolled steel. Assortment

GOST 8278−83 steel roll-formed Channels. Assortment

GOST 8281−80 steel Channels roll-formed angle. Assortment

GOST 8282−83 steel sections S-shaped angle. Assortment

GOST 8283−93 steel sections trough angle. Assortment

The Angles GOST 8509−93 hot-rolled steel angle. Assortment

GOST 8510−86 angle steel hot rolled angle. Assortment

GOST 8568−77 Sheets steel with rhombic and lentil corrugation. Specifications

GOST 9234−74 steel bend sections with trapezoidal sheet corrugated. Assortment

GOST 9454−78 Metals. Test method for impact strength at low, room and elevated temperatures

GOST 9651 (ISO 783−89) Metals. Methods of tensile tests at elevated temperatures

GOST 10551−75 steel sections corrugated. Assortment

GOST 11701−84 (ISO 6892−84) Metals. Methods tensile tests of thin sheets and strips

GOST 11474−76 steel sections. Specifications

GOST 12344−2003 Steel alloyed and high alloy. Methods for determination of carbon

GOST 12345−2001 (ISO 671−82, ISO 4935−89) Steel alloyed and high alloy. Methods of determining sulphur

GOST 12346−78 (ISO 439−82, ISO 4829−1-86) Steel alloyed and high alloy. Methods for determination of silicon

GOST 12347−77 Steel alloyed and high alloy. Methods for determination of phosphorus

GOST 12348−78 (ISO 629−82) Steel alloyed and high alloy. Methods for determination of manganese

GOST 12350−78 Steel alloyed and high alloy. Methods for determination of chromium

GOST 12351−2003 (ISO 4942:1988, ISO 9647:1989) Steel alloyed and high alloy. Methods for determination of vanadium

GOST 12352−81 Steel alloyed and high alloy. Methods for determination of Nickel

GOST 12354−81 Steel alloyed and high alloy. Methods for determination of molybdenum

GOST 12355−78 Steel alloyed and high alloy. Methods for determination of copper

GOST 12356−81 Steel alloyed and high alloy. Methods for determination of titanium

GOST 12357−84 Steel alloyed and high alloy. Methods for determination of aluminium

GOST 12359−99 (ISO 4945−77) Steels carbon, alloyed and high alloy. Methods for determination of nitrogen

GOST 12361−2002 Steel alloyed and high alloy. Methods for determination of niobium

GOST 12365−84 Steel alloyed and high alloy. Methods for determination of zirconium

GOST 13229−78 Profiles steel bent Zeta. Assortment

GOST 14019−2003 (ISO 7438:1985) Materials of metal. Method of bend test

GOST 14635−93 the steel cold-shaped special Profiles for car building. Assortment

GOST 14637−89 (ISO 4995−78) rolled plate from carbon steel of ordinary quality. Specifications

GOST 16504−81 System of state testing products. Testing and quality control. Key terms and definitions

GOST 16523−97 rolled sheets from carbon steel quality and common quality of General purpose. Specifications

GOST 17745−90 of Steel and alloys. Methods for the determination of gases

GOST 18321−73 Statistical quality control. Methods of random selection of piece products

GOST 18895−97 Steel. Method of photoelectric spectral analysis

GOST 19425−74 steel I-Beam and steel channels special. Assortment

GOST 19771−93 Corners steel bent angle. Assortment

GOST 19772−93 Corners steel bent angle. Assortment

GOST 19903−74 hot-rolled steel sheets. Assortment

GOST 22536.0−87 carbon Steel and unalloyed cast iron. General requirements for methods of analysis

GOST 22536.1−88 carbon Steel and unalloyed cast iron. Methods for determination of total carbon and graphite

GOST 22536.2−87 carbon Steel and unalloyed cast iron. Methods of determining sulphur

GOST 22536.3−88 carbon Steel and unalloyed cast iron. Methods for determination of phosphorus

GOST 22536.4−88 carbon Steel and unalloyed cast iron. Methods for determination of silicon

GOST 22536.5−87 (ISO 629−82) carbon Steel and unalloyed cast iron. Methods for determination of manganese

GOST 22536.7−88 carbon Steel and unalloyed cast iron. Methods for determination of chromium

GOST 22536.8−87 carbon Steel and unalloyed cast iron. Methods for determination of copper

GOST 22536.9−88 carbon Steel and unalloyed cast iron. Methods for determination of Nickel

GOST 22536.10−88 carbon Steel and unalloyed cast iron. Methods for determination of aluminium

GOST 22536.11−87 carbon Steel and unalloyed cast iron. Methods for determination of titanium

GOST 22536.12−88 carbon Steel and unalloyed cast iron. Methods for determination of vanadium

GOST 22727−88 the rolled sheet. Methods of ultrasonic testing

GOST 25577−83 Profiles steel bent closed welded square and rectangular. Specifications

GOST 26020−83 I-Beams steel hot rolled with parallel flanges. Assortment

GOST 27809−95 Cast iron and steel. Methods for spectrographic analysis

GOST 28473−90 Iron, steel, ferroalloys, chromium and manganese metal. General requirements for methods of analysis

GOST 28870−90 Steel. Methods tensile tests of rolled plates in thickness direction.

Note — When using this standard appropriate to test the effect of reference standards in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet or in the annual information index „National standards“ published as on January 1 of the current year, and the editions of the monthly information index „National standards“ for the current year. If the reference standard is replaced (changed), when using this standard should be guided by replacing (amended) standard. If the reference standard is cancelled without replacement, then the situation in which the given link applies to the extent that does not affect this link.

3 Terms and definitions


This standard applies the following terms with respective definitions:

3.1 sheet products: Products of rectangular cross-section with a large ratio of width to thickness.

3.1.1 rolled sheets: Products of thickness less than 3.00 mm, a width of 500 mm or more with a rolled or cut edge and comes in sheets or rolls.

3.1.2 rolled plate: Products with thickness of 3.00 mm and a width of 500 mm or more with a rolled or cut edge and comes in sheets or rolls.

3.2 rental broadband universal: Products with thickness from 6 mm to 60 mm, widths from 200 mm to 1050 mm with rolled edge and delivered in sheets.

3.3 rolled shapes: rolled, which is tangent at least at one point of the contour of the cross section the cross section intersects.

3.3.1 area: rolled with a cross section of a right angle with equal or unequal sides and rounded inner edges.

3.3.2 I-beam: a rolled, having a cross-section resembling two United bases of the letter „T“, with the sloping flanges or parallel flanges.

3.3.3 channel: rolled cross-section resembling the letter „P“ with rounded internal edges, with sloping flanges or parallel flanges.

3.4 the bent profiles: the Profiles of various cross-sections, manufactured on roll forming mills of hot rolled sheet metal, having a cross-section of the same along the entire length.

3.5 it is permitted to use the following terms for rental:

3.5.1 sheet: Sheet, rolled sheets and universal broadband rental.

3.5.2 coils: Sheet and plate products in coils.

3.5.3 profiles: rolled sections and cold-formed sections.

3.6 hot-rolled steel; GK: rolling, the resulting hot plastic deformation and subsequent cooling in calm air.

3.7 heat treatment; THE Technological process of heating to a predetermined temperature and cooling it at a specified rate or on the tranquil air.

3.7.1 leave; On: Technological process of heating the rental is below A temperatureГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, soaking and cooling it with the required speed.

3.7.2 normalization; H: heating process to temperatures above the AГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияand then cooling it with a calm air.

3.7.3 improving; Y: process involving heating to A higher temperatureГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, quenching and high tempering.

3.8 accelerated cooling; UO: Technological process of forced cooling of rolled after hot deformation at a rate exceeding the rate of cooling in calm air.

3.9 controlled rolling; KP: the Technological process of rolling with the regulation and control of temperature and degree of deformation during the rolling process.

3.10 reinforcing heat treatment with special heating; UTO: the Technological process of accelerated cooling of rolled after heating to A higher temperatureГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия.

3.11 hardening heat treatment from the rolling heat; USBC: the Technological process of accelerated cooling of rolled after hot plastic deformation.

3.12 A ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияand AГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия: Designates the temperature point of phase transformation:

AГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия: the Temperature at which begins the formation of austenite during heating.

AГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия: the Temperature at which the transformation of ferrite into austenite when heated.

3.13 surface in the area of rolled edge Narrow line rental „as laminated“ in width, not displaying wide-face plate and universal broadband rental for a nominal amount.

3.14 corrosion resistance: Ability of metal to resist the corrosive effects of the environment.

3.15 fire resistance: Ability of metal to retain its physical and mechanical properties when exposed to fire in case of fire.

4 Classification and assortment

4.1 the hire is made:

— types:

— leaf (sheet, plate);

— universal broadband;

— shapes (angles, I-beams, channels);

— curved profile;

— the name of steel S235, S245, S255, S345, S345K, С355, С355−1, С355К, С355П, S390, S390−1, S440, С550, С590, where the letter „S“ means steel construction, numbers 235−590 arbitrarily designate the yield strength of rolled in N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, figure 1 is a variant of the chemical composition, the letter „K“ — steel of high corrosion resistance, „U“ steel with high resistance;

— as edge;

— as of delivery.

4.2 In form, dimensions and limit deviations according to him, the production shall conform to the requirements:

— rolled sheet GOST 8568, GOST 19903;

rental universal broadband — 82 GOST;

— rolled shapes:

angles angle — GOST 8509;

angles angle — GOST 8510;

the I-beam — GOST 8239, GOST 19425; GOST 26020;

channels — GOST 8240, GOST 19425;

profiles bent — 7511 GOST, GOST 8278, 8281 GOST, GOST 8282, 8283 GOST, GOST 9234, 10551 GOST, GOST 13229, 14635 GOST, GOST 19771, 19772 GOST, GOST 25577.

4.3 the Scheme and examples of the legend of the rent is given in Appendix A.

5 Technical requirements

5.1 Main features

5.1.1 Chemical composition of steel

5.1.1.1 Chemical composition of steel by ladle sample analysis must conform to the standards given in table 1.

Mass fraction of nitrogen in steel at a basic oxygen furnace production shall be not more than 0,008%, with smelting in electric furnaces — not more than 0,010%, shall be allowed not more than 0,012% when the mass fraction of aluminum of at least 0.02% for both methods of smelting.

5.1.1.2 In the production of a deviation in the mass fraction of the elements of the standards are shown in table 1, in accordance with table 2.

5.1.1.3 Steel is subjected to secondary treatment technology manufacturer. When this mass fraction of residual calcium should not exceed 0,006% bucket sample and 0.002% in the finished rolled products.

Allowed mass fraction of calcium in the product is not to define and ensure manufacturing technology. Allowed steel S235, S245, S255 and steel for structural shapes S345, С355, С355−1 and S390 are not subjected to secondary treatment.

5.1.2 the status of the delivery must ensure that the required properties rental. To ensure the required properties of sheet metal, all steel allowed the use of heat treatment, controlled rolling, controlled rolling with accelerated cooling hardening heat treatment with a special rolling or heat.

Rolled plates of steel S390, S390−1, S440, it is recommended to put after the improvement, or controlled rolling with accelerated cooling. Rolled plates of steel С355П, С550 and С590 it is recommended to use after controlled rolling with accelerated cooling.

Allowed way a hardening heat treatment with a special rolling or heat to produce hot rolled plates of steel S390 with the chemical composition of steel S345, and a method of hardening heat treatment from the rolling heat to produce structural shapes with a flange width up to 12 mm inclusive of S345 steel with the chemical composition of steel S245 and S255.

A method of manufacturing stipulate in the order, if not specified, it is defined by the manufacturer and specifies in the instrument of quality.

5.1.3 rolled steel all items are made with the guarantee of weldability. Guarantee of weldability of rolled steel S235, S245, S255, provided the chemical composition by ladle sample, and rental of other items of steel advanced carbon equivalent in accordance with table 1.

Table 1 — Chemical composition of steel by ladle sample analysis

Name-
Nova
nie steel
Mass fraction of elements, %
C, not more than Mn Si S, not more P Cr Ni Cu Mo V Nb AI Ti Zr

CГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, not more than

S235 0,22 not more than 0,60
not more than 0.05 0,040 not more than 0,040 not more than 0.30 not more than 0.30 not more than 0.30 - - - - - - -
S245 0,22 no more than 1,00
0,06-
0,16
0,025 not more than 0,040 not more than 0.30 not more than 0.30 not more than 0.30 - - - not more than 0.02 - - -
S255 0,17 no more than 1,00
0,15-
0,30
0,025 not more than 0,035 not more than 0.30 not more than 0.30 not more than 0.30 - - - 0,02-
0,05
not more than 0,030 - -
S345 0,15 1,30−1,70 not more than 0,80
0,025 not more than 0,030 not more than 0.30 not more than 0.30 not more than 0.30 - - - 0,015-
0,06
not more than 0,035 - 0,45
S345K 0,12 not more than 0,60
0,17-
0,37
0,025 0,020-
0,120
0,50-
0,80
0,30-
0,60
0,30-
0,50
- - - 0,08-
0,15
not more than 0,035 - 0,45
С355 0,14 1,00−1,80 0,15-
0,80
0,025 0.025
not more than 0.30 not more than 0.30 not more than 0.30 - - - 0,02-
0,06
not more than 0,035 - 0,45
С355−1 0,15 0,60−0,90 0,40-
0,70
0,015 not more than 0,017
0,60-
0,90
0,30-
0,60
0,20-
0,40
- - - 0,02-
0,06
not more than 0,035 - 0,45
С355К 0,15 0,80−1,10 0,40-
0,60
0,015 not more than 0,020
0,50-
0,70
0,50-
0,70
0,40-
0,70
- - - 0,02-
0,06
0,010-
0,035
not more than 0,010 0,45
С355П 0,10 0,60−0,90 0,15-
0,35
0,015 not more than 0,020
not more than 0,80 not more than 0.30 not more than 0.30 0,08-
0,20
not more than 0,09 0,02-
0,09
0,02-
0,06
0,010-
0,035
- 0,45
S390 0,12 1,30−1,70 0,15-
0,50
0,010 not more than 0,017
not more than 0.30 not more than 0.30 not more than 0.30 - not more than 0.12 not more than 0,09 0,02-
0,06
not more than 0,035 - 0,46
S390−1 0,12 0,60−0,90 0,80-
1,10
0,010 not more than 0,017
0,60-
0,90
0,50-
0,80
0,40-
0,60
- - - 0,02-
0,06
0,010-
0,035
- 0,46
S440 0,12 1,30−1,70 0,15-
0,50
0,010 not more than 0,017
not more than 0.30 not more than 0.30 not more than 0.30 - not more than 0,09 not more than 0,09 0,02-
0,06
0,010-
0,035
- 0,46
С550 0,10 1,30−1,95 0,15-
0,35
0,007 not more than 0,015
not more than 0.30 0,15-
0,35
not more than 0.30 not more than 0.35 not more than 0.10 0,03-
0,10
0,02-
0,06
0,010-
0,035
- 0,47
С590 0,10 1,30-
1,95
0,15-
0,35
0,004 not more than 0,015
not more than 0.30 0,10 — 0,30 0,10 — 0,30 not more than 0.35 not more than 0.10 0,03-
0,10
0,02-
0,06
0,010-
0,035
- 0,51
Notes

1 In steel С355−1 and S390−1 allowed mass fraction of V to 0.08% or less Nb to 0.06%, while the mass fraction of Cr should not exceed 0,30%, Ni — 0.20 per cent.

2 In steel S345, С355, S390 allowed mass fraction of Nb-0.06% V to 0.08%.

3 In of steel S390, intended for the manufacture of structural shapes, is allowed the mass fraction of C is not more than 0.15% in the absence of Nb microalloying steel.

4 In steels S390, S440, С550 and С590 the total mass fraction of V+Nb shall not exceed 0,12%.

5 S345 Steel for the manufacture of rolled plates may be used in building constructions until 01.01.2017.

6 the Sign „— „means that the chemical composition on ladle analysis the samples are not normalized.



Table 2 — maximum deviations in chemical composition in the production of

The name of the element Limit deviations in mass fraction of elements in steel products, %
S235
S245-S255 S345-С590
C
- - +0,02
Mn
+0,050 +0,050 ±0,010
Si - +0,030
-0,020
±0,05
Cr
- - ±0,05
Ni
- - ±0,05
Cu
- - ±0,05
Mo
- - ±0,03
S
+0,006 +0,005 +0,005
P
+0,006 +0,005 +0,005
N
+0,002 +0,002 +0,002
V
- - +0,02
Nb
- - +0,02
Ti
- - +0,010
Notes

1 By agreement between manufacturer and consumer tolerances for the mass fraction of carbon steel C345-С590 shall not exceed plus 0,010%.

2 For steel S255 maximum deviation in the mass fraction of carbon in products is +0,020%.

3 For elements, mass fraction of which is limited to the upper limit, use only the positive limit deviation.

4 the Sign „-" means that the maximum deviations on the element is not normalized.



Table 3

Normalized feature
Category
1
2 3 4 5 6 7
The impact strength KCU at the temperature of test, °C:
-20
+
-40
+
-70
+
The impact strength KCV at the temperature of test, °C:
0
+
-20
+
-40
+
-60
+

5.1.4 Mechanical properties of the rolled products should conform to the requirements of:

— for sheet and universal broadband, including blanks for roll-formed profiles — table 4;

for shaped — tables 5.

5.1.4.1 Test the impact strength of rolled all steel except S235, carried out at the request of the consumer in accordance with table 3.

5.1.4.2 For rental from steel, S245, S255, S345, С355, С355−1, С355К test results of impact strength on samples of KCV type 11 according to GOST 9454 are not rejection symptom until 01.01.2017, but are specified in the instrument of quality. With this same period, abolish mandatory testing of rolled products the samples of a type 1 KCU according to GOST 9454.

5.1.5 Test rolled bending at 180° mandrel diameter, equal to two thicknesses of the samples without the formation of cracks and breaks guaranteed by the production technology.

5.1.6 At the request of the consumer rolled sheet with a thickness of 20 mm and more are made with guaranteed properties in the thickness direction of hire with groups quality 28870 churchyard, which specify in the order.

5.1.7 Quality of surface and the edge of the sheet and universal broadband rental

5.1.7.1 On the surface of the products (except surface rolled edges) must be no flaws, rips, rolled and burnt crusts and bubbles-bubbles, accordions, roll out of cracks, and rolling the prisoner rolled out of the dirt and katanoi scale.

Unacceptable surface defects are removed a gentle sweep with a width of not less than five times the depth. Formed during cleaning of the recess should have smooth transitions. The cleaning is carried out with an abrasive tool or methods that do not cause changes in properties rental.

The depth of the Stripping surface defects should take the size of the rental for the ultimate sub-zero deviation in thickness.

The stripped surface should not have scratches visible to the naked eye. At the boundary of the sweep must be no sharp edges.

Table 4 — Mechanical properties of plates and wide universal rental and preparations for roll-formed profiles

Nai
Meno-
tion of steel
Thickness, mm Mechanical properties

Pre-
Affairs current
honorГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия

Time
men-
ing company of Tule-
nie ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия

The fre-
Sitel-
ing. -
tion ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, %

Impact strength, j/cmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, not less

Not less than KCU KCV KCU after mechanical
IC aging
temperature, °C
-20
-40 -70 0 -20 -40 -60 +20
S235 from 2,0 to 3,9 incl. 235
360 - - - - - - - - -
4,0
235 360 - - - - - - - - -
S245 from 2,0 to 3,9 incl. 245
370 20 - - - - - - - -
4,0 30 235
370 24 29 - - 34 - - - 29
S255 from 2,0 to 3,9 incl. 255
380 20 - - - - - - - -
4,0 10 » 245
380 25 29 29 - 34 34 - - 29
St. 10 " 20 " 245
370 25 29 29 - 34 34 - - 29
" 20 " 40 " 235
370 Twenty five 29 29 - 34 34 - - 29
S345 from 2,0 to 3,9 incl. 345
490 21 - - - - - - - -
" 4,0 " 10,0 " 345
490 21 - 39 34 - 34 34 - 29
" 10 " 20,0 " 325
470 21 - 34 29 - 34 34 - 29
" 20,0 " 40,0 " 305
460 21 - 34 29 - 34 34 - 29
" 40,0 " 60,0 " 285
450 21 - 34 29 - 34 34 - 29
" 60 " 80 " 275
440 21 - 34 29 - 34 34 - 29
" 80 " One hundred sixty " 265
430 21 - 34 29 - 34 34 - 29
S345K from 4,0 to 10 incl. 345
470 20 - 39 - - - - - -
С355 from 8,0 to 16 incl. 355
470 21 - - - - 34 34 - -
St. 16 " 40 " 345
470 21 - - - - 34 34 - -
" 40 " 60 " 335
470 21 - - - - 34 34 - -
" 60 " 80 " 325
460 21 - - - - 34 34 - -
" 80 " 100 " 315
460 21 - - - - 34 34 - -
" 100 " 160 " 295
460 21 - - - - 34 34 - -
С355−1 from 8 to 16 incl. 355
470 21 - 34 34 - 34 34 - -
St. 16 " 40 " 345
470 21 - 34 34 - 34 34 - -
" 40 " 50 " 335
470 21 - 34 34 - 34 34 - -
С355К from 8,0 to 16 incl. 355
470 21 - 34 34 - 34 34 - -
St. 16 " 40 " 345
470 21 - 34 34 - 34 34 - -
" 40 " 50 " 335
470 21 - 34 34 - Thirty four 34 - -
С355П from 8,0 to 16 incl. 355
470 21 - - - - 34 34 - -
St. 16 " 40 " 345
470 21 - - - - 34 34 - -
S390−1 from 8,0 to 50 incl. 390
520 20 - - - - - 34 34 -
S390 from 8,0 to 50 incl. 390
520 20 - - - - - 34 29 -
S440 from 8,0 to 50 incl. 440
540 20 - - - - - 66 66 -
С550 from 8,0 to 50 incl. 540
640 17 - - - - - 66 66 -
С590 from 8,0 to 40 incl. Five hundred ninety
685 14 - - - - - 66 66 -

Notes

1 the Maximum value of the temporary resistance,"ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия" for rental of steel S390, S390−1, S440, С550, С590 should not exceed the established standards for more than 160 N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия.

2 the Sign «-" means that the indicator is not standardized.

3 elongation (ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) of sheet metal with thickness from 2.0 mm to 2.8 mm inclusive of steels S235 must be at least 28%, S245 — no less than 26%, S255 — not less than 25%.

4 С355П For steel, the yield strength ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияat a temperature of 600 °C should be not less than 200 N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, tensile strength ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия — not less than 240 N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия.



Table 5 — Mechanical properties of structural shapes

Nai
Meno-
tion of steel
The thickness of rolling, mm Mechanical properties

Pre-
Affairs current
honorГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия

Time
men-
ing company of Tule-
nie ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия

The fre-
Sitel-
ing. -
tion ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, %

Impact strength, j/cmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, not less

Not less than KCU KCV KCU after mechanical
IC aging
temperature, °C
-20
-40 -70 0 -20 -40 +20
S245 from 4 to 20 incl. 245
370 25 29 - - 34 - - 29
» 20 " 40 " 235
370 24 29 - - 34 - - 29
S255 from 4 to 10 incl. 255
380 25 29 29 - 34 34 - 29
" 10 " 20 " 245
370 25 29 29 - 34 34 - 29
" 20 " 40 " 235
370 24 29 29 - 34 34 - 29
S345 from 4 to 10 incl. 345
480 21 - 39 34 - 34 - -
" 10 " 20 " 325
470 21 - 34 29 - Thirty four - -
" 20 " 40 " 305
460 21 - 34 - 34 - -
S345K from 4 to 10 incl. 345
470 20 - 39 - - - - -
With 355 from 8 to 16 incl. 355
470 21 - 34 34 - 34 - -
" 16 " 40 " 345
470 21 - 34 34 - 34 - -
С355−1 from 8 to 16 incl. 355
480 21 - 34 34 - 34 - -
" 16 " 40 " 345
480 21 - 34 34 - 34 - -
S390 from 8 to 10 incl. 390
520 20 - 34 34 - 34 34 -
" 10 " 20 " 380
500 20 - 34 34 - 34 34 -
" 20 " 40 " 370
490 20 - 34 34 - 34 34 -
Notes

1 For rolled steel S345, С355, С355−1 definition of impact strength KCU at a temperature of minus 70 °C is carried out on the profiles with a thickness up to 11 mm incl., in coordination with the consumer -of a thickness up to 40 mm incl.

2 the Sign «-" means that the indicator is not normalized.


The square separately cleaned of surface rent shall not exceed 100 cmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия. Reducing the thickness of the rolled over negative maximum deviations after Stripping shall not exceed 5% of the nominal thickness, but should not be more than 3 mm. While the total area of all the stripped plots of this depth should not exceed 2% of the leaf area.

When coincidence Stripping on both sides of the rentals allowable depth of Stripping is determined as the sum of the depth of the sweeps on each side of the hire and must not exceed the negative limit deviation on thickness.

Permitted without the removal of local (area not exceeding 100 cmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) defects (rabiza, risk, fingerprints) with a total area not exceeding 10% of the leaf area, and depth (height), not deducing the size of the rental for the minus tolerances for the thickness.

5.1.7.2 For trimming the side and end edges of the sheet and ends of universal broadband rental ought to not be delaminations, cracks, flaws, burrs height of more than 2 mm.

5.1.7.3 Crushing and bending the edges after pruning should take the flatness of the rolled for the limit deviations according to GOST 19903.

5.1.7.4 surface rental in the area of the rolled edges should be free of delaminations, flaws, cracks, captivity, pollution, katanoi scale, wooloowin and scratches, which eliminates the rent for the minimum dimensions in thickness, and bubbles-bubbles that gets the rental for the maximum thickness.

5.1.7.5 the depth of the defects on the rolled edge of the sheet and universal broadband rental should not exceed half of the maximum deviations in width and should not output the width of the rental for a nominal amount.

5.1.8 the quality of the surface and the ends of structural shapes shall conform to the requirements of GOST 535, roll-formed profiles — standard 11474.

5.1.9 Welding and sealing of defects on the surface and edges of plates and wide universal rental not allowed.

5.1.10 Bundle sections is not allowed.

5.1.11 According to customer’s demands rolled sheet is subjected to ultrasonic inspection. Flats for continuity must meet one of the classes 0, 1 or 2 according to GOST 22727.

The need for ultrasonic testing, grade continuity and volume controls stipulate in the order.

5.2 Labeling and packaging of rolled according to GOST 7566 with additions:

for plates and wide universal — according to GOST 14637, GOST 16523;

for roll — formed profiles according to GOST 11474.

6 acceptance Rules

6.1 Products take parties. The party should consist of the rental of the same species, the same size in thickness, one name began, one melting ladle, and one state of delivery.

6.2 Each batch of rental must be accompanied by a quality document issued in accordance with GOST 7566 with additions:

— plates and universal broadband rental — according to GOST 14637;

— rolled sheets — GOST 16523;

for roll — formed profiles according to GOST 11474.

In addition, document the quality of each batch should contain:

— the designation of the rental;

— delivery condition;

— the value of the relative contraction during the tensile test in the thickness direction of the sheet, as determined in accordance with 5.1.6;

— at the request of the consumer — the value of acceptance numbers for the two and six tests, determined in accordance with the requirements of Annex B.

6.3 To check the mechanical properties of rental from the party are selected from:

— structural shapes — two profiles;

— universal broadband and sheet — two sheets;

— sheet metal rolls — two rolls.

6.4 sample size for testing the surface quality and size determine:

— structural shapes — according to GOST 535;

— plates and wide universal rental — according to GOST 14637, GOST 16523;

— roll — formed profiles according to GOST 11474.

6.5 the Volume of testing of sheet metal — according to GOST 14637 (paragraph 3.8).

6.6 If unsatisfactory test results in bending, impact bending, re-testing is carried out in accordance with GOST 7566.

If unsatisfactory test results for yield strength, ultimate strength and relative elongation of the repeated tests performed on sample selected in accordance with Annex B.

The results of the tests apply to the entire party.

If unsatisfactory test results during ultrasonic testing the manufacturer carries out tests on each sheet of the party.

7 control Methods

7.1 Sampling for the determination of chemical composition — GOST 7565.

7.2 Chemical analysis of steel — GOST 12344, 12345 GOST, GOST 12346, 12347 GOST, GOST 12348, 12350 GOST, GOST 12351, 12352 GOST, GOST 12354 series, GOST 12355, 12356 GOST, GOST 12357, 12359 GOST, GOST 12361, 12365 GOST, GOST 17745, GOST 18895, GOST 22536.0 to GOST 22536.1, 22536.2 GOST, GOST 22536.3, 22536.4 GOST, GOST 22536.5, 22536.7 GOST, GOST 22536.8, 22536.9 GOST, GOST 22536.10, 22536.11 GOST, GOST 22536.12, GOST 27809, GOST 28473, [1] or other methods providing the required accuracy of the analysis.

In case of disagreement between the manufacturer and the customer used methods of analysis set forth in this standard.

7.3 Carbon equivalent CГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, %, is calculated by the formula:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, (1)


where C, Mn, Si, Cr, Ni, Cu, V, P — mass fraction of the elements.

7.4 controlling the surface quality of rolled products is carried out according to GOST 16523, plate and universal broadband rental — according to GOST 14637. Control the size and the shape deviations is carried out for:

— sheet metal — according to GOST 19903;

— universal broadband rental — GOST 82.

Control of surface quality, sizes and the shape deviations is carried out for:

— structural shapes — according to GOST 535;

— roll — formed profiles according to GOST 11474.

7.5 stratification of the rent control inspection of edges and ends without the use of magnifying devices.

If necessary, the quality of the edge of the sheet and universal broadband rental check by removing the chip, wherein the chip splitting is a sign of discontinuity flaws of metal.

7.6 testing of sheet metal is carried out according to GOST 22727. Scan (continuous or discontinuous linear) is set by the manufacturer. The depth of the marginal ice zone under the control of the maximum allowable length of discontinuities shall be not less than 50 mm.

7.7 Sampling for mechanical and technological tests carried out according to GOST 7564. Flamed and universal broadband rolled samples cut lengthwise from a sheet of rolled across the direction of rolling.

7.8 each of the controlled rental units selected for the sample. Of each sample are made for:

— tensile tests — one sample;

— drop test, bend — two samples for the respective test conditions;

— tensile tests in the thickness direction of the sample.

Control of roll-formed sections is carried out on the workpiece.

7.9 Test bars in tension is carried out on the samples five times the length according to GOST 1497, four-time length — according to GOST 11701. For products with thickness less than 3.00 mm width of the sample should be 15 mm. the yield strength is determined by the tension diagram.

7.10 yield strength and tensile strength at elevated temperatures is determined according to GOST 9651.

7.11 evaluation of the results of tensile tests carried out according to methodology described in Appendix B.

7.12 Testing the impact strength of the rolling steel with a nominal thickness of 5 mm to 10 mm is carried out according to GOST 9454 on samples of type 2, 3, 12, 13. For rental with a nominal thickness of 10 mm or more, the test for impact strength is carried out according to GOST 9454 on samples of type 1, 11.

7.13 Testing the impact strength after mechanical aging is carried out according to GOST 7268.

7.14 Test bars in tension in the thickness direction is carried out according to GOST 28870.

8 Transportation and storage

8.1 Transportation and storage of rental — according to GOST 7566 with additions:

for plates and wide universal — according to GOST 14637, GOST 16523;

for roll — formed profiles according to GOST 11474.

9 Requirements for safety and environmental protection

9.1 the Products are fire and explosion proof, non-toxic and requires no special measures during transportation, storage and processing.

10 manufacturer’s Warranty

10.1 the Manufacturer guarantees the compliance of products with requirements of this standard under the conditions of transportation and storage.

Annex a (mandatory). Diagram and symbols are examples of rolled products and profiles for ordering

Appendix A
(required)

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия

The hot rolled sheet increased accuracy (A), high flatness (PV), with cut edges (O), size (10x1000x2000) mm according to GOST 19903, of steel S390, in the improved state (a), category 6:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияsubject to 5.1.2


The hot rolled sheet normal accuracy (B), improved flatness (PU), mill edge (NO), size (8x1000x2000) mm according to GOST 19903, steel S345K, in hot-rolled condition (CC):

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия


The hot rolled sheet in coils, of high accuracy (A), mill edge (NO), size (10x1500) mm according to GOST 19903, S245 steel in hot-rolled condition (CC):

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия


Area hot rolled angle normal accuracy of rolling (In), dimension (75x75x6) mm according to GOST 8509−93, S245 steel in hot-rolled condition (CC):

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия


I-beam hot rolled high precision rolling (B), 20 under GOST 8239−89, steel S255, in hot-rolled condition (CC):

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия


Steel channels number 18 with the sloping flanges according to GOST 8240−97, steel С355−1, in hot-rolled condition (CC):

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия


The profile is roll-formed C-shaped angle of the workpiece normal accuracy of rolling (B), height 300 mm, width 60 mm flange width 50 mm, thickness of 5 mm according to GOST 8282−83, of steel S235:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия

Appendix B (mandatory). Methods of control and evaluation of mechanical properties of rolled

Appendix B
(required)


This method is intended to evaluate the compliance of the mechanical properties of the party rental requirements.

Given the likelihood of the implementation of the fluidity limit, strength and elongation of each batch and the total volume of supply of hire is reached by the statistical evaluation of the level and heterogeneity of the properties of the metal at a certain technological process and the control procedure provided for in this standard, and implemented by the manufacturer.

B. 1 General provisions

B. 1.1 Terms, concepts and definitions in accordance with GOST 16504, and other regulatory documentation.

B. 1.2 the Probability of the implementation of the standard for yield strength, ultimate strength and relative elongation in each batch of hire should be not lower than 0,95.

B. 1.3 Evaluation of conformity between mechanical properties of each batch to the requirements of the standard is based on the test results of samples selected and manufactured in accordance with 6.3, 7.7, 7.8 of the standard. For hire allowed the estimation of mechanical properties using regression equations showing the relationship between yield strength, temporary resistance and elongation on the one hand and chemical composition by ladle sample, the size profile recorded and other technological factors on the other.

B. 2 Requirements for sampling, the statistics of distributions

B. 2.1 Mechanical properties of rolled products made from one of steel, one mill, one or a group of close sizes of sections, one variant of the chemical composition, one state delivery form the General population.

The estimation of parameters that reflect the level and the heterogeneity of the controlled characteristics of the rental in the General population, conducted on the basis of the results of the primary tests that form the selection.

B. 2.2 the Sample should be representative and include all the results of the initial tests over a sufficiently long period of time (at least six months) during which the technological process did not undergo directional changes (change of units, methods of casting, the change of the raw materials, the bulk of the ingot, the temperature regime of rolling, etc.). The minimum sample size (N) 250 parties-heats. To obtain representative samples of the possible grouping of profiles of different sizes in one set with the test of heterogeneity of the total sample using the student t-test.

B. 2.3 the aggregation of test results constituting the sample, determine the sample mean (ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) by the formula:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, (B. 1)


where XГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, XГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияXГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия — the set of values of a random variable X, forming the sampling and unbiased estimates of the standard deviation (S) according to the formula:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, (B. 2)


and the difference (h) between the ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияnormative and value (C), are shown in tables 4 and 5 of the standard.

The value of h to the yield strength and strength shall be not less than 1,645S. If this condition for any of the samples fails, the manufacturer of this type of rental under this standard is not allowed.

B. 2.4 the Distribution of characteristics in the sample is assumed corresponding to the normal law. Verification of the hypothesis about normal distribution law is carried out in accordance with normative-technical documentation. The level of significance the consent of the empirical and normal distributions should not be lower than 0,01.

Estimating the abnormality of test results in the sample, is carried out according to normative-technical documentation at level of significance equal to 0.05.

B. 2.5 After the launch of the new rolling equipment, or after modification of processes and the absence, in this regard, statistical estimates of properties for rental yield stress and strength are allowed to take the value S=28 N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, and elongation S=3%. However, for all three characteristics

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия. (B. 3)


With the accumulation of test results the values of ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияand S are adjusted.

B. 2.6 According to this standard the estimate standard deviation of the yield strength, temporary resistance and elongation in the party determines the manufacturer experimentally. Tested at least three random batches of hire included in this population. From each batch shall be tested not less than 50 samples, selected randomly. An accident is provided under GOST 18321.

For later use, was adopted the value of SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияobtained as the arithmetic average of the sample means squared deviations in the tested parties, calculated according to the formula (B. 2).

If the yield strength obtained value of SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияis less than 10 N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, taken to be SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия=10 N/mmГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия.

The value of SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияis adjusted at least once a year using the methods described above or by the method of proportions on the test results rolled in, forming the General set.

Data accumulation is carried out during the first year of delivery with the adjustment at least once a year.

B. 3 Evaluation of conformity between mechanical properties of batches of rolled and bent profiles the requirements of the standard

B. 3.1 Mechanical properties party rental evaluate the results of tensile tests of two samples (n=2). Arithmetic means (ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) of these results for yield strength and elongation shall be not less than the corresponding values of the acceptance number (CГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) determined by the formula:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, (B. 4)

where ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия.

B. 3.2 If, in a tensile test of two samples requirement B. 3.1 of the present application is not performed for at least one of the characteristics shall be tested four samples taken from four different sheets or rods. The test is considered satisfactory if the yield strength, temporary resistance, relative elongation ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияnot less than CГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияwhen n=6.

If necessary, the sampling will use the results of only the first two tests.

B. 3.3 the statistical evaluation of conformity of mechanical properties of the parties rolled the requirements of the standard with the help of regression equations the minimum number of parties subjected to direct tensile tests, depends on the smaller of the values of the parameter Zcalculated for the yield strength and elongation according to the formula:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия. (B. 5)


When ZГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияis 2.0 — tested at least one of the 10 lots;

with 1.6ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияZ<2.0 to be tested at least one of 5 parties;

when Z<1,6 — tested each batch.

B. 3.4 Estimation of reliability prediction of mechanical properties of the regression equations is done using control charts or other methods.

B. 4 Evaluation of conformity of mechanical properties of rolled hire requirements

B. 4.1 Evaluation of compliance level of the mechanical properties of the party of products delivered in coils, the requirements of the standard is carried out using the statistical dependency based on the difference in the level of strength and plastic characteristics of external coils and a middle coil.

B. 4.2 Statistical dependence can be expressed by the regression equations showing the relationship of the yield strength, temporary resistance and elongation in the middle of the coil with the test results of outer coils, the chemical composition by ladle sample, sheet thickness, temperature of rolling and winding into a roll, as well as other detected parameters obtained by using non-destructive methods of control.

B. 4.3 the Sample used to estimate the level of heterogeneity of mechanical properties of products delivered in rolls, based on test results of samples randomly selected from the middle part of the coil when cutting into sheets. The sample includes the test results of the samples taken from at least 50 parties-heats. From each batch, samples taken from an equal number of coils (at least two) from each roll selected an equal number of samples. For sample values ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия, S and h.

Other requirements samples for characterizing the mechanical properties of the rolled products supplied in rolls, must conform to B. 2.1-B. 2.5 of this Annex.

Sample characteristics as arguments in the regression equations, are in the appropriate amounts.

B. 4.4 Prediction and evaluation of conformity of the properties of the batch of products delivered in coils, the requirements of the standard equations of linear and multiple regression allowed when the value of the ratio of the pair and, respectively, the multiple correlations are below 0.4 and is carried out in accordance with B. 3.1, B. 3.2, B. 3.4 of this Annex.

B. 4.5 If the requirement of B. 4.4 of the present application is not running in a part of the value of the correlation coefficient, then the manufacturer conducts the assessment of compliance of properties of products delivered in coils, in accordance with the requirements set out in B. 4.5.1-B. 4.5.3.

B. 4.5.1 For yield strength and elongation determined by the experimental value of SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияfor which there is a rental of not less than three random parties, members of this population. From each party select three rolls, each roll not less than 20 samples evenly along the length of the roll.

Other requirements for the determination of SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия — in accordance with B. 2.6 of the present application.

B. 4.5.2 For the yield strength, temporary resistance and elongation, in addition to the samples prepared in accordance with the requirements of 4.3, in parallel, formed a sample of a random variable — ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия. Value ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия — the difference between average value of test results of two samples taken from the outer turns of the two coils of the party and the arithmetic mean of the test results the same number of samples taken from the middle part of the same rolls.

For the value ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияdetermined by the sample mean (ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) and standard deviation (SГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия).

B. 4.5.3 For assessment of conformity of party rental the requirements of the standard test of two samples drawn from the outer coils of two random rolls of the party and determine the arithmetic mean (ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия) of the results of these tests.

The calculated values of yield strength and elongation determined by the formula:

ГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условия. (B. 6)

Calculated values should not be less than the acceptance number CГОСТ 27772-2015 Прокат для строительных стальных конструкций. Общие технические условияdefined by the formula (B. 4) of this Appendix, when n=2.