GB/T 34475-2017 English PDF (GBT34475-2017)
GB/T 34475-2017 English PDF (GBT34475-2017)
GB/T 34475-2017: Urea grade austenitic stainless steel bars
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
Urea Grade Austenitic Stainless-Steel Bars
ISSUED ON: OCTOBER 14, 2017
IMPLEMENTED ON: JULY 01, 2018
Issued by: General Administration of Quality Supervision, Inspection and Quarantine;
Standardization Administration of PRC.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative References ... 4
3 Terms and Definitions ... 6
4 Classification and Code ... 6
5 Ordering Contents ... 7
6 Size, Shape and Weight ... 7
7 Technical Requirements ... 8
8 Test Methods ... 12
9 Inspection Rules ... 13
10 Package, Marking and Quality Certificate ... 14
Appendix A (Informative) Comparison of Grades in This and Other Similar Standards ... 15
Appendix B (Normative) Corrosion Rate Conversion Factor Form ... 16
Urea Grade Austenitic Stainless-Steel Bars
This Standard specifies the classification and code, ordering contents, size, shape, weight, technical requirements, test methods, inspection rules, package, marking and quality certificate of urea grade austenitic stainless-steel bars.
This Standard is applicable to the rolled or wrought urea grade austenitic stainless- steel bars (hereinafter referred to as steel bar) with nominal size no greater than 400mm. The stainless-steel bars with nominal size greater than 400mm can be used as reference.
2 Normative References
The following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) are applicable to this document.
GB/T 222 Permissible Tolerances for Chemical Composition of Steel Products 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 223.19 Methods for Chemical Analysis of Iron, Steel and Alloy - The Neocuproine-Chloroform Extraction Photometric Method for the Determination of Copper Content
GB/T 223.25 Methods for Chemical Analysis of Iron, Steel and Alloy - The Dimethylglyoxime Gravimetric Method for the Determination of Nickel Content GB/T 223.28 Methods for Chemical Analysis of Iron, Steel and Alloy - The a- Benzoinoxime Gravimetric Method for the Determination of Molybdenum Content GB/T 223.36 Methods for Chemical Analysis of Iron, Steel and Alloy - The Neutral Titration Method for the Determination of Nitrogen Content after Distillation Separation
GB/T 223.59 Iron, Steel and Alloy - Determination of Phosphorus Content - Bismuth Phosphomolybdate Blue Spectrophotometric Method and Antimony
Phosphomolybdate Blue Spectrophotometric Method
GB/T 223.64 Iron, Steel and Alloy - Determination of Manganese Content - Flame Atomic Absorption Spectrometric Method
GB/T 223.79 Iron and Steel - Determination of Multi-Element Contents - X-Ray Fluorescence Spectrometry (Routine Method)
GB/T 223.85 Steel and Iron - Determination of Sulfur Content - Infrared Absorption Method after Combustion in an Induction Furnace
GB/T 223.86 Steel and Iron - Determination of Total Carbon Content - Infrared Absorption Method after Combustion in an Induction Furnace
GB/T 226 Test Method for Macrostructure and Defect of Steel by Etching
GB/T 228.1 Metallic Materials - Tensile Testing - Part 1: Method of Test at Room Temperature
GB/T 230.1 Metallic Materials - Rockwell Hardness Test - Part 1: Test Method (Scales A, B, C, D, E, F, G, H, K, N, T)
GB/T 231.1 Metallic Materials - Brinell Hardness Test - Part 1: Test Method GB/T 702-2017 Hot-Rolled Steel Bars - Dimensions, Shape, Weight and
GB/T 908-2008 Forged Bars - Dimensions, Shape, Weight and Tolerances
GB/T 1979 Standard Diagrams for Macrostructure and Defect of Structural Steels GB/T 2101 General Requirement of Acceptance Packaging Marking and
Certification for Section Steel
GB/T 2975 Steel and Steel Products - Location and Preparation of Samples and Test Pieces for Mechanical Testing
GB/T 4162 Forged and Rolled Steel Bars - Method for Ultrasonic Examination GB/T 7736 Ultrasonic Inspecting Method for Macro-structure and Imperfection of Steel
GB/T 10561-2005 Steel - Determination of Content of Nonmetallic Inclusions - Micrographic Method Using Standards Diagrams
GB/T 11170 Stainless steel - Determination of multi-element contents - Spark discharge atomic emission spectrometric method (Routine method)
GB/T 13305 Micrographic Method for Determining Area Content of the α-phases in Stainless Steels
GB/T 15711 Steel Products - Method for Etch Test of Tower Sample
GB/T 17505 Steel and Steel Products - General Technical Delivery Requirements GB/T 20066 Steel and Iron-Sampling and Preparation of Samples for the
Determination of Chemical Composition
GB/T 20123 Steel and Iron - Determination of Total Carbon and Sulfur Content Infrared Absorption Method after Combustion in an Induction Furnace (Routine Method)
GB/T 20124 Steel and Iron - Determination of Nitrogen Content - Thermal Conductimetric Method after Fusion in a Current of Inert Gas
GB/T 25151.3 Fabrication and Inspection Method for High Pressure Urea
Equipment - Part 3: Intergranular Corrosion Tendency Test for Ultra Low-Carbon Chromated Nickel Molybdenum Austenitic Stainless Steel of Urea Grade
GB/T 25151.4 Fabrication and Inspection Method for High Pressure Urea
Equipment - Part 4: Intergranular Corrosion Tendency Test Specimen Preparation for Ultra Low-Carbon Chromated Nickel Molybdenum Austenitic Stainless Steel of Urea Grade
YB/T 4395 Steel Determination of Molybdenum, Niobium and Tungsten Contents - Inductively Coupled Plasma Atomic Emission Spectrometric Method
YB/T 5293 Metallic Materials-Forging Test
3 Terms and Definitions
For the purposes of this document, the following terms and definitions apply. 3.1 Urea grade austenitic stainless steel
Ultra-low carbon chromium nickel molybdenum austenitic stainless steel for critical equipment in urea production.
4 Classification and Code
4.1 Steel bars are divided into the following categories according to the use and 6.3 The steel bars usually have a delivery length of 2000mm~12000mm. After the consultation between the supplier and the purchaser, indicated in the contract, it can also be delivered as per specified length or multiple length. The allowable deviation for the length of the rolled steel bar is +50 0 mm, while the allowable deviation for the length of the forged steel bar is +80 0 mm.
6.4 Steel bars are usually delivered at the actual weight.
7 Technical Requirements
7.1 Grade and chemical composition
7.1.1 The grade and chemical composition (smelting analysis) of steel shall conform to the provisions of Table 1.
7.1.2 The allowable deviation for the chemical composition of steel bar shall conform to the provisions of GB/T 222.
7.2 Smelting method
Steel shall be refined and smelted outside the furnace. After the consultation between the supplier and the purchaser, indicated in the contract, other smelting methods that meet the requirements of this Standard shall also be used.
7.3 Delivery state
Generally, the pressure processing steel bar is delivered in the hot-rolled or forged state; while the cutting processing steel bar is generally delivered in the solid solution treatment state.
7.4 Mechanical properties
7.4.1 The cutting processing steel bar or sample blank after heat treatment shall be tested for mechanical properties; their mechanical properties shall conform to the provisions of Table 2.
7.4.2 According to the requirements of the purchaser, indicated in the contract, the pressure processing steel bar can be tested for mechanical properties. The sample blank, after the heat treatment solid solution treatment recommended in Table 2, the mechanical properties shall conform to the provisions of Table 2.
10 Tower shape 2
Different steel bars equivalent
to the head of the steel ingot;
continuous casting steel in
any different steel bars
11 Size and shape Piece by piece The whole steel bar
12 Surface quality Piece by piece The whole steel bar Visual examination a When the electroslag steel is batched according to the sub-furnace number, in addition to the inspection items required for sampling one by one; the sampling quantity for other inspection items is 1. When it is batched according to the mother furnace number, except for the chemical composition, for which each electroslag furnace number shall be sampled 1; the sampling quantity for other inspection items shall be specified in the table.
9 Inspection Rules
9.1 Inspection and acceptance
The inspection and acceptance of steel bars shall be carried out as per the supplier’s technical quality supervision department.
9.2 Batching rules
Steel bars shall be inspected and accepted in batches. Each batch consists of the steel bars with the same grade, the same furnace number, the same processing method, the same size, the same delivery state (the same heat treatment furnace number). The steel smelted by electroslag re-melting is allowed to be delivered by smelting mother furnace number in batches under the conditions that the process is stable, and guarantee the technical requirements of this Standard.
9.3 Sampling locations and sampling quantities
The sampling locations and sampling quantities of each batch of steel bars shall conform to the provisions of Table 7.
9.4 Reinspection and judgement rules
9.4.1 The reinspection and judgement rules shall be as stipulated in GB/T 17505. 9.4.2 If the supplier can ensure the qualification of the steel bar, the inspection items against the steel bars with the same furnace number, such as mechanical properties, α phase, macrostructure, non-metallic inclusions, etc. are allowed to replace the material by blank, and replace the small by the large.