YB/T 4212-2010 English PDF (YBT4212-2010)

This standard specifies the terms and definitions, order content, dimensions, shape, weight and allowable deviations, technical requirements, test methods, inspection rules, packaging, markings and quality certificates of hot-rolled wide flat steel for structural use. This standard is applicable to strip-shaped wide flat steel which has a thickness of 4 mm ~ 40 mm, a width of 150 mm ~ 600 mm, in a rectangular cross-section for structural use, hot-rolled on all four sides.

YB/T 4212-2010
YB
FERROUS METALLURGY INDUSTRY STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
ICS 77.140.70
H 44
Hot-rolled wide flat for construction
ISSUED ON: NOVEMBER 10, 2010
IMPLEMENTED ON: MARCH 01, 2011
Issued by: Ministry of Industry and Information Technology of PRC
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Terms and definitions ... 6
4 Order content ... 6
5 Size, shape, weight and allowable deviation ... 7
6 Technical requirements ... 11
7 Test method ... 12
8 Inspection rules ... 13
9 Packaging, marking and quality certificate ... 14
Hot-rolled wide flat for construction
1 Scope
This standard specifies the terms and definitions, order content, dimensions, shape, weight and allowable deviations, technical requirements, test methods, inspection rules, packaging, markings and quality certificates of hot-rolled wide flat steel for structural use.
This standard is applicable to strip-shaped wide flat steel which has a thickness of 4 mm ~ 40 mm, a width of 150 mm ~ 600 mm, in a rectangular cross-section for structural use, hot-rolled on all four sides.
2 Normative references
The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) is applicable to this standard.
GB/T 222 Permissible tolerances for chemical composition of steel products GB/T 223.3 Methods for chemical analysis of iron, steel and alloy - The diantipyryl methane phosphomolybdate gravimetric method for the
determination of phosphorus content
GB/T 223.5 Steel and iron - Determination of acid-soluble silicon and total silicon content - Reduced molybdosilicate spectrophotometric method
GB/T 223.9 Methods for chemical analysis of iron, steel and alloy - The chrome azurol S photometric method for the determination of aluminum
content
GB/T 223.11 Iron, steel and alloy - Determination of chromium content - Visual titration or potentiometric titration method
GB/T 223.14 Methods for chemical analysis of iron, steel and alloy - The N- benzoyl-N-phenylhydroxylamine extraction photometric method for the
determination of vanadium content
GB/T 223.17 Methods for chemical analysis of iron, steel and alloy - The diantipyryl methane photometric method for the determination of titanium content
determination of carbon content
GB/T 223.72 Iron, steel and alloy - Determination of sulfur content -
Gravimetric method
GB/T 228 Metallic materials - Tensile testing at ambient temperature
GB/T 229 Metallic materials - Charpy pendulum impact test method
GB/T 232 Metallic materials - Bend test
GB/T 700 Carbon structural steels
GB/T 1591 High strength low alloy structural steels
GB/T 2101 General requirement of acceptance, packaging, marking and
certificate for section steel
GB/T 2975 Steel and steel products - Location and preparation of samples and test pieces for mechanical testing
GB/T 4336 Carbon and low-alloy steel - Determination of multi-element
contents - Spark discharge atomic emission spectrometric method (routine method)
GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition
YB/T 081 Rule for rounding off of numerical values and judgement of testing values for technical standards of metallurgy
3 Terms and definitions
The following terms and definitions apply to this standard:
3.1
Wide flat
Wide flat steel refers to a steel with a width greater than or equal to 150 mm and a thickness usually greater than 4 mm, generally delivered in straight bars, not in coils, with edges and corners on the sides. Wide flat steel is obtained by hot rolling on four sides (or by box-shaped hole).
4 Order content
a) This standard number
When the wide flat steel is delivered according to the theoretical weight, the nominal size shall be adopted for calculating the theoretical weight. The density of carbon steel is 7.85 g/cm3. Other steel types shall be as specified in accordance with the corresponding standards.
6 Technical requirements
6.1 Designation and chemical composition
The designation and chemical composition of steel shall meet the requirements of GB/T 700 and GB/T 1591. The allowable deviation of the chemical
composition of the finished wide flat steel shall meet the requirements of GB/T 222.
6.2 Smelting method
Steel is smelted by converter or electric furnace.
6.3 Delivery status
Wide flat steel is delivered straight in hot rolled status.
6.4 Mechanical properties and process properties
The mechanical properties and process properties of wide flat steel shall meet the requirements of GB/T 700 and GB/T 1591.
6.5 Surface quality
6.5.1 The surface of the wide flat steel shall not have defects such as scars, cracks, folds, inclusions, blisters, oxide scales that are harmful to use. There shall be no delamination of wide flat steel.
6.5.2 The surface of the wide flat steel is allowed to have local defects such as thin oxide scale, rust, slight pitting and scratches that do not affect the use. The unevenness shall not exceed half of the thickness tolerance of the wide flat steel; meanwhile it shall ensure the allowable minimum thickness of wide flat steel.
6.5.3 The surface defects of wide flat steel are allowed to be cleaned up. The cleaning place shall be smooth and without edges and corners, meanwhile the allowable minimum thickness of the wide flat steel shall be guaranteed. However, welding repair or blockage is not allowed.
6.5.4 For edge cracks and other defects caused by rolling, the depth shall not exceed half of the width tolerance of the wide flat steel, meanwhile the wide flat steel shall not be made smaller than the nominal width.