GB/T 31922-2015Hot-rolled steel sheets and strips of higher yield strength with improved formability (English PDF)

Foreword

This Standard is drafted according to the rules given in the GB/T 1.1-2009.

This Standard uses redrafting method to modify ISO 5951.2013 (E) Hot-rolled

steel sheet of higher yield strength with improved formability.

Compared with ISO 5951.2013, this Standard makes many adjustments in

structure. Clause numbers of this Standard and ISO 5951.2013 are listed in the

control list in Appendix A.

There are technical differences between this Standard and ISO 5951.2013. The

clauses involved in these differences have been indicated via the vertical single

lines (|) drawn at the outer margin positions. The list of corresponding technical

differences and causes is given in Appendix B.

This Standard makes the following editorial modifications.

— DELETE the contents in the table of contents, references and foreword

of the ISO 5951.2013. REWRITE the foreword in accordance with the

standard practice of our country.

— MODIFY the word "this International Standard" to "this Standard" or "this

document".

— In the normative references, this Standard makes direct reference to the

corresponding national standards.

— USE the decimal point "." to replace the comma "," used as decimal point.

— According to the expression in our national standards, RE-INDUCE the

expression on the required ordering information, dimension, shape,

weight, allowable deviation, delivery status, oiling, test methods, surface

quality and inspection rules.

— Clearly REQUEST to use the upper yield strength ReH as minimum yield

strength.

— ADD Appendix A (Informative) "Structural changes of this Standard

compared with the ISO 5951.2013".

— ADD Appendix B (Informative) "List of the corresponding technical

differences between this Standard and ISO 5951.2013 and the causes".

This Standard was proposed by China Iron and Steel Association.

Hot-rolled steel sheets and strips of higher yield

strength with improved formability

1 Scope

This Standard specifies the classification and code, ordering information,

dimension, shape, weight, allowable deviation, technical requirements, test

methods, inspection rules, packaging, marks and quality certificate of the hot-

rolled steel sheets and strips of higher yield strength with improved formability.

This Standard is applicable to the hot-rolled steel strips of higher yield strength

with good formability and the thickness of 1.0mm to 6.0mm, the steel sheets

produced by the crosscutting of steel strips, and the steel strips produced by rip

cutting (hereinafter referred to as "steel sheets and strips").

2 Normative references

The following documents are essential to the application of this document. For

dated references, only the versions with the dates indicated are applicable to

this document. For undated references, only the latest versions (including all

the amendments) are applicable to this document.

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

diantipyrylmethane phosphomolybdate gravimetric method for the

determination of phosphorus content

GB/T 223.9 Iron, steel and alloy – Determination of aluminium content –

Chrom azurol S photometric method

GB/T 223.11 Iron, steel and alloy – Determination of chromium content –

Visual titration or potentiometric titration method (GB/T 223.11-2008, ISO

4937.1986, MOD)

GB/T 223.14 Methods for chemical analysis of iron, steel and alloy – The N-

Benzoy-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

diantipyrylmethane photometric method for the determination of titanium

content

GB/T 223.18 Methods for chemical analysis of iron, steel and alloy – The

sodium thiosulfate separation iodimetric method for the determination of

copper content

GB/T 223.23 Iron, steel and alloy – Determination of nickel content – The

dimethylglyoxime spectrophotometric method

GB/T 223.26 Iron, steel and alloy – Determination of molybdenum content –

The thiocyanate spectrophotometric method

GB/T 223.40 Iron, steel and alloy – Determination of niobium content by the

sulphochlorophenol S spectrophotometric method

GB/T 223.60 Methods for chemical analysis of iron, steel and alloy – The

perchloric acid dehydration gravimetric method for the determination of

silicon content

GB/T 223.63 Methods for chemical analysis of iron, steel and alloy – The

sodium (potassium) periodate photometric method for the determination of

manganese content

GB/T 223.68 Methods for chemical analysis of iron, steel and alloy – The

potassium iodate titration method after combustion in the pipe furnace for the

determination of sulfur content

GB/T 223.69 Iron, steel and alloy – Determination of carbon contents – Gas-

volumetric method after combustion in the pipe furnace

GB/T 223.75 Iron, steel and alloy – Determination of boron content –

Methanol distillation-curcumin photometric method

GB/T 223.76 Methods for chemical analysis of iron, steel and alloy – The

flame atomic absorption spectrometric method for the determination of

vanadium content

GB/T 228.1 Metallic materials – Tensile testing – Part 1. Method of test at

room temperature (GB/T 228.1-2010, ISO 6892-1.2009, MOD)

GB/T 247 General rule of package mark and certification for steel plates

(sheets) and strips

GB/T 709 Dimension, shape, weight and tolerances for hot-rolled steel

sheets and strips (GB/T 709-2006, ISO 7452.2002, ISO 16160.2000, NEQ)

4 Required ordering information

5 Dimension, shape, weight and allowable deviation

The dimension, shape, weight and allowable deviation of steel sheets and strips

shall conform to the provisions in the GB/T 709.

6 Technical requirements