for Chemical Analysis of Iron, Steel and Alloy; The anion-exchange Separation-sulphochlorophenol S Photometric Method for the Determination of Niobium Content
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 223.62 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 223.68 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 228 Metallic Materials--Tensile Testing at Ambient Temperature (neq ISO 1143, ISO 6892)
GB/T 242 Metal Materials—Tube—Drift-Expending Test (eqv ISO 8493)
GB/T 244 Metallic Materials-Tube - Bend Test (eqv ISO 8491)
GB/T 245 Metallic Materials-Tube - Flanging Test (eqv ISO 8494)
GB/T 246 Metal Materials—Tube—Flattening Test (eqv ISO 8492)
GB/T 2102 Acceptance Packing Marking and Quality Certification of Steel Pipe
GB/T 2975 Steel and Steel Products--Location and Preparation of Test Pieces for Mechanical Testing (eqv ISO 377)
GB/T 3323 Methods for Radiographic Inspection and Classification of Radiographs for Fusion Welded Butt Joints in Steel
GB/T 4334.1 Method of 10 Percent Oxalic Acid Etch Test for Stainless Steels
GB/T 4334.2 Method of Ferric Sulfate-Sulfuric Acid Test for Stainless Steels
GB/T 4334.3 Method of 65 Percent Nitric Acid Test for Stainless Steels
GB/T 4334.4 Method of Nitric-Hydrofluoric Acid Test for Stainless Steels
GB/T 4334.5 Method of Copper Sulfate-Sulfuric Acid Test for Stainless Steels
GB/T 4334.6 Method of 5 Percent Sulfuric Acid Test for Stainless Steels
GB/T 6397-1980 Metallic Materials--Test Pieces for Tensile Testing (neq ISO 6892)
GB/T 7735 Steel Tubes—The Inspection Method on Eddy Current Test (eqv ISO 9304)
GB/T 11170 Method for Photoelectric Emission Spectroscopic Analysis of Stainless Steel
3 Classification and designation
It is classified into four types according to supply state:
Welded condition W
Heat treated state T
Cold drawn (roll) state WC
Burnishing (polishing) state SP
Steel tube is divided into three grades according to dimensional precision:
Ordinary grade PA
Higher grade FB
Top grade PC