1.0.1 This code is formulated with view to implementing national technical and economic policies in the steel structure welding, to achieving technical advancement, economic rationality, safety and usability, and to ensuring quality and energy conservation and environmental protection.
1.0.2 This code is applicable to the welding of structures bearing static load or dynamic load and with steel thickness not less than 3mm in industrial and civil steel structure engineering. The applicable welding methods in this code include shielded metal arc welding, gas-shielded arc welding, flux cored wire selfshield arc welding, submerged-arc welding, ESW, EGW, stud welding and their combination.
1.0.3 Steel structure welding must comply with the current relevant provisions of the nation on safety technology and labor protection, etc.
1.0.4 Steel structure welding shall not only comply with this code, but also shall comply with those specified in the in the current relevant standards of the nation.
2 Terms and Symbols
2.1 Terms
2.1.1 Hydrogen relief heat treatment
The post-weld heat treatment method in which the welding joints of the structural steel, which is likely to have cold crack, are heated to certain temperature (250℃~350℃) after welding and held for a while so as to accelerate the diffusion of hydrogen in the welding joints and delayed crack due to the accumulation of diffusible hydrogen.
2.1.2 Stress relief heat treatment
The post-weld heat treatment method in which the welding joints are heated to the certain temperature (550℃~650℃) below the base metal Ac1 line after welding and held for a while so as to reduce welding residual stress and improve joint structure property.
2.1.3 Weld access hole
The weld penetrating hole which is set at the corresponding position at the cross of member welds in order to guarantee continuity of main weld and facilitate to welding operation.
2.1.4 Prequalification of WPS
The welding procedures that the provisions in this code may be adopted without passing welding procedure qualification test, under the conditions of meeting some specific welding methods, parameters, steels, joint form and welding consumable combination correspondingly specified in this code.
2.1.5 Temperature of welding circumstance
The temperature of the surrounding environment of weldment during welding.
2.1.6 Flux cored wire selfshield arc welding
The method that the weld zone is protected by the slag and gas formed by the reaction of welding wire flux core at high temperature, without additionally adding gas or welding flux for protection.
2.1.7 Testing
The technical operation composed of testing of one or several properties of a given product, test treatment or services providing according to specified procedures.
2.1.8 Inspection
The checking of materials, staff, procedures, process or results and the determination of its compliance to the specific requirement or that to general requirement on the basis of professional judgment.
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Basic Requirement
4 Materials
5 Design of Welding Connections
5.1 General Requirements
5.2 Form and Size of Weld Groove
5.3 Theoretical Throat of Weld
5.4 Welding Nodal Points of Combined Welding Member
5.5 Technics for Avoiding the Nodal Point of Lamellar Tearing
5.6 Welding Connection Design of Member Production and Field Installation
5.7 Design of Welding Connections Bearing Dynamic Load and Anti-earthquake
6 Welding Procedure Qualification
6.1 General Requirement
6.2 Substitute Principles of Welding Procedure Qualification
6.3 Requalification
6.4 Preparation of Test Pieces and Samples
6.5 Testing
6.6 Prequalification of WPS
7 Welding Procedures
7.1 Preparation of Base Metal
7.2 Requirement of Welding Consumables
7.3 Assemble Requirement of Welding Joint
7.4 Tack Weld
7.5 Welding Environment
7.6 Preheat and Interpass Temperature Control
7.7 Post-weld Hydrogen Relief Heat Treatment
7.8 Post-weld Stress Relief Treatment
7.9 Weld Tab and Backing
7.10 Technic Requirement of Welding Procedure
7.11 Control of Welding Deformation
7.12 Repairs
7.13 Correction
7.14 Back Gouging
7.15 Temporary Welds
7.16 Striking and Extinguish of Arc
7.17 ESW and EGW
8 Inspection
8.1 General Requirement
8.2 Weld Inspection of Structure Bearing Static Load
8.3 Weld Inspection of Structure Requiring Fatigue Assessment
9 Weld Strengthening and Reinforcement
Appendix A Form, Size and Marking Method for Welding Joint Groove of Steel Structure
Appendix B Format of WPQR
Appendix C Testing of ESW Weld of Box Members
Explanation of Wording in This Code
List of Quoted Standards