1 Scope
This standard specifies the order information, classification and codes, dimension, appearance, weight, permissible deviation, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of structural bar steels with specified hardenability bands.
This standard is applicable to hot-rolled and hot forging bar steel (hereinafter referred to as steel) with specified hardenability bands for machinery manufacture. The hardenability of steel is determined according to end quenching method or calculated according to formula.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, the latest edition of the normative document is applicable to this standard. For undated references, the latest edition of the normative document referred to applies.
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 223.5 Steel and Iron - Determination of Acid-soluble Silicon and Total Silicon Content - Reduced Molybdosilicate Spectrophotometric Method
GB/T 223.11 Iron Steel and Alloy - Determination of Chromium Content - Visual Titration or Potentiometric Titration Method
GB/T 223.13 Methods for Chemical Analysis of Iron, Steel and Alloy - The Ammonium Ferrous Sulfate Titration Method for the Determination of Vanadium 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/T 223.16 Methods for Chemical Analysis of Iron, Steel and Alloy - the Chromotropic Acid Photometric Method for the Determination of Titanium 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 223.19 Methods for Chemical Analysis of Iron, Steel and Alloy - The Neocuproine-chloroform Extraction Photometric 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 223.25 Methods for Chemical Analysis of Iron, Steel and Alloy - The Dimethylglyoxime Gravimetric Method for the Determination of Nickel Content
GB/T 223.26 Iron Steel and Alloy - Determination of Molybdenum Content - The Thiocyanate Spectrophotometric Method
GB/T 223.53 Methods for Chemical Analysis of Iron, Steel and Alloy - The Flame Atomic Absorption Spectrophotometric Method for the Determination of Copper Content
GB/T 223.54 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 Methods for Chemical Analysis of Iron, Steel and Alloy - The Sodium Arsenite-sodium Nitrite Titrimetric Method for the Determination of Manganese Content
GB/T 223.59 Iron Steel and Alloy - Determination of Phosphorus Content - Bismuth Phosphomolybdate Blue Spectrophotometric Method and Antimony Phosphomolybdate Blue 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 223.61 Methods for Chemical Analysis of Iron, Steel and Alloy - The Ammonium Phosphomolybdate Volumetric Method for the Determination of Phosphorus Content
GB/T 223.62 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 Iron Steel and Alloy - Determination of Manganese Content - Flame Atomic Absorption Spectrometric Method
GB/T 223.67 Iron Steel and Alloy - Determination of Sulfur Content - Methylene Blue Spectrophotometric Method
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
Foreword I
1 Scope
2 Normative References
3 Order Information
4 Classification and Codes
5 Dimension, Appearance, Weight and Permissible Deviation
6 Technical Requirements
7 Test Method
8 Inspection Rules
9 Packaging, Marking and Quality Certificate
Appendix A (Informative) Calculation Method for Ideal Critical Diameter DI of Steel
Appendix B (Informative) Comparison between Partial Designations in Table 1 of This Standard and Foreign Designations
