GBT 6725-2002 冷弯型钢

1 Scope
This standard specifies the contents related to scope, specification, testing method, test rules, packing, label and certification of quality of cold formed steel sections.
This standard is applicable to cold-roll of cold-working or cold formed steel sections produced by hot continuously rolled steel plate and steel strips on continuity cold-roll-forming machine unit.
This standard is not applicable to formed steel which is produced in the method of dragging, stamping and bending, and so on.

2 Normative References
The following provisions contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to, or revisions of (excluding corrigendum contents) ,or Revised Edition do not apply. However, it is encouraged that every part of this standard to research the latest edition of these documents. For undated references, the latest edition of the normative document referred to applies.
GB/T222 Method of sampling steel for determination of chemical composition and permissible variations for product analysis
GB/T223.3 Methods for chemical analysis of iron, steel and alloy--The diantipyryl methane phosphomolybdate gravimetric method for the determination of phosphorus content
GB/T223.5 Methods for chemical analysis of iron steel and alloy. The reduced molybdosilicate spectrophotometric method for the determination of acid-soluble silicon content
GB/T 223.10 Methods for chemical analysis of iron, steel and alloy—The cupferron separation-chrome azurol S photometric method for the determination of aluminium content
GB/T 223.11 Methods for chemical analysis of iron, steel and alloy—The ammonium persulfate oxidation volumetric method for the determination of chromium content
GB/T 223.12 Methods for Chemical Analysis of Iron, Steel and Alloy-The Sodium Carbonate Separation-diphenyl Carbazide Photometric Method for the Determination of Chromium Content.
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/T223.16 Methods for chemical analysis of iron, steel and alloy—The chromotropic acid photometric method for the determination of titanium content.
GB/T 223.19 Method of chemical analysis on steel and alloy / the neocuproine-chloroform extraction photometric method for the determination of copper content.
GB/T223.23 Methods for chemical analysis of iron, steel and alloy-The dimethylglyoxime spectrophotometric method for the determination of nickel content.
GB/T 223.24 Method of chemical analysis on steel and alloy / the dimethylglyoxime spectrophotometric method for the determination of nickel content.
GB/T223.36 Methods for chemical analysis of iron steel and alloy-- The neutral titration method for the determination of nitrogen content after distillation separation.
GB/T 223.37 Method of chemical analysis on steel and alloy / the indophenol blue photometric method for the determination of nitrogen content after distillation.
GB/T223.49 Methods for chemical analysis of iron steel and alloy—Extraction separation-chlorophosphonazo mA spectrophotometric method for the determination of the total rare earth content.
GB/T223.53 Methods for chemical analysis of iron, steel and alloy--The flame atomic absorption spectrophotometric method for the determination of copper content.
GB/T223.54-1987 Methods for Chemical Analysis of Iron, Steel and Alloy--The Flame Atomic Absorption Spectrophotometric Method for the Determination of Nickel Content
GB/T 223.58 Method of chemical analysis on steel and alloy / the extraction-absorption catalytic polarographic method for the determination of manganese content.
GB/T 223.59 Method of chemical analysis on steel and alloy /the sodium arsenite-sodium nitrite titrimetric method for the determination of phosphorus content.
GB/T 223.60 Method of chemical analysis on steel and alloy /the perchloric acid dehydration for the determination of silicon content.
GB/T223.61 Methods for chemical analysis of iron, steel and alloy--The ammonium phosphomolybdate volumetric method for the determination of phosphorus content.
GB/T223.62 Methods for chemical analysis of iron, steel and alloy--The butyl acetate extraction photometric method for the determination of phosphorus 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 223.64 Method of chemical analysis on steel and alloy /the flame atomic absorption spectrometric method for the determination of manganese content.
GB/T223.67 Methods for chemical analysis of iron, steel and alloy—The reducing distillation-methylene blue photometric method for the determination of sulfur content.
GB/T 223.68 Method of chemical analysis on steel and alloy /the combustion potassium iodate volumetric method for the determination of sulfur content
GB/T 223.69 Methods for chemical analysis of Iron, steel and alloy- The gas-volumetric method after combustion in the tube furnace for the determination of carbon content.
GB/T 223.71 Method of chemical analysis on steel and alloy /the gravimetric method after combustion in the pipe furnace for the determination of carbon content.
GB/T 223.72 Method of chemical analysis on steel and alloy /the alumina chromatographic separation-barium sulfate gravimetric method for the determination of sulphur content.
GB/T 228 Metallic materials/tensile testing method in room temperature
GB/T 232 Metallic materials/bend testing methods
GB/T 699 Carbon Constructional Quality Steel
GB/T 700 Carbon structural steels
GB/T 1591 High-Strength Low-Alloy Structural Steels
GB/T 2101 General rule of acceptance, package, mark and certification for profile steel
GB/T 2975 Steel and steel products--Location and preparation of test pieces for mechanical testing
GB/T4171 Superior atmospheric corrosion resisting structural steel
GB/T4239 Cold rolled stainless steel strips
GB/T 17505 Steel and Steel Products General Technical Delivery Requirements