This standard specifies the ordering, classification, code, dimension，shape，weight and tolerance, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of hot-rolled round carbon steel bars and rods for standard parts.
This standard is applicable to hot-rolled round carbon steel bars and rods (hereinafter referred to as round steel bars and rods) for manufacturing cold upsetting or hot upsetting screws, nuts, bolts and rivets.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards. For undated references, the latest edition of the normative document referred to applies
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 Methods for Chemical Analysis of Iron, Steel and Alloy; The Reduced Molybdosilicate Spectrophotometric Method for the Determination of Acid-soluble Silicon Content
GB/T 223.11 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 223.18 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 Methods for Chemical Analysis of Iron, Steel and Alloy - The Dimethylglyoxime Spectrophotometric Method for the Determination of Nickel Content
GB/T 223.24 Methods for Chemical Analysis of Iron, Steel and Alloy - the Extraction Separation - The Dimethylglyoxime Spectrophotometric Method for the Determination of Nickel Content
