GB/T 47706.1-2026Rail welding - Part 1: General requirements and test methods (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting.

This document is Part 1 of GB/T 47706 "Rail Welding". GB/T 47706 "Rail Welding" has the following parts published.

---Part 1: General Requirements and Test Methods this document modifies and adopts ISO 23300-1:2021 "Railway infrastructure - Rail welding - Part 1: General requirements for rail welding".

Test methods.

The technical differences between this document and ISO 23300-1:2021, and the reasons therefor, are as follows.

a) The terms and definitions of "railway authorities" and "operators" have been removed to better reflect my country's national conditions;

b) Requirements for drop hammer tests on welded rail joints have been added (see 6.8) to comply with Chinese application requirements;

c) The requirements for non-destructive testing have been revised (see 7.2) to better suit my country's national conditions;

d) The straightness inspection location (see 7.3.1) has been changed to conform to my country's national conditions;

e) The straightness acceptance standards of Japan and the European Union (see 7.3.2) have been deleted, which is not suitable for my country's national conditions;

f) The technical requirements for static bending tests under rail tension in Japan and the European Union (see Appendix A) have been removed, which is not suitable for my country's national conditions;

g) The technical requirements for static bending tests of railhead tension in Japan and the European Union (see Appendix B) have been deleted, which is not suitable for my country's national conditions;

h) Requirements for the loading rate of the static bending testing machine have been added (see Appendix A and Appendix B) to better suit my country's national conditions;

i) The load cycle requirements for fatigue testing have been increased (see Appendix C and Appendix D) to better suit my country's national conditions;

j) The test method for hardness testing has been modified (see Appendix G) to suit my country's national conditions;

k) The requirements for the drop hammer test height of rail welded joints have been changed (see Appendix H) to conform to my country's national conditions;

l) The qualification requirements for nondestructive testing personnel have been increased (see Appendices J to L) to better suit my country's national conditions;

m) The technical requirements for ultrasonic testing, magnetic particle testing, and dye penetrant testing have been revised (see Appendices J to L) to conform to my country's national conditions;

n) Appendix M has been deleted, and the "Straightness Requirements in my country" in Appendix M has been added to 7.3.2.

The following editorial changes have been made to this document.

a) Change the standard title to "Rail Welding Part 1: General Requirements and Test Methods";

b) The description of the static bending test in section 6.3 has been deleted;

c) The overview of Appendix A, "Static Bending Test under Tension at the Rail Bottom," has been deleted;

d) The overview of Appendix B, "Static Bending Test of Rail Head under Tension," has been deleted;

e) The overview of Appendix C, "Three-point bending fatigue test," has been deleted;

f) The overview of Appendix D, "Four-point bending fatigue test", has been removed.

Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents.

This document was proposed and is under the jurisdiction of the National Railway Administration.

Introduction

Rail welding is a key technology in the railway track industry. It can reduce noise and vibration at rail joints, improve ride comfort, and reduce [other issues].

Maintenance costs. To ensure rail welding quality, improve train operation reliability, increase welding efficiency, and promote the introduction of new technologies, [the following costs are considered].

GB/T 47706 "Rail Welding" is hereby established. This document is intended to consist of five parts.

---Part 1: General Requirements and Test Methods. The purpose is to standardize the general requirements and test methods for various rail welding methods.

---Part 2: Aluminothermic Welding. The purpose is to standardize type testing, welding processes, and quality requirements for aluminothermic welding of rails.

---Part 3: Gas Pressure Welding. The purpose is to standardize the type testing, welding process, and quality requirements for gas pressure welding of rails.

---Part 4: Flash Welding. The purpose is to standardize the type testing, welding process, and quality requirements for flash welding of rails.

---Part 5: Arc Welding. The purpose is to standardize type testing, welding procedures, and quality requirements for arc welding of steel rails.

Rail welding

Part 1: General Requirements and Test Methods

1 Scope

This document specifies the rail welding methods, general procedures, type tests, acceptance of welded joints, and requirements for welding units/welding personnel/inspectors.

Personnel requirements.

This document applies to the following rail welding methods.

---Flash welding;

---Gas pressure welding;

---Aluminothermic welding;

--- Arc welding.

This document applies to welding newly manufactured steel rails of the same type and strength grade, ranging from 43kg/m to 75kg/m. Specific details for each welding method are provided.

The physical requirements and test methods are specified in the relevant standards.

This document is limited to butt welding of standard section rail ends, excluding rail repair welding, and does not include safety regulations for welding operations.

Qualification requirements for individuals or organizations engaged in rail welding.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

GB/T 230.1 Metallic materials—Rockwell hardness test—Part 1: Test methods (GB/T 230.1-2018, ISO 6508-1.

2023, MOD)

GB/T 4340.1 Metallic materials – Vickers hardness test – Part 1: Test methods (GB/T 4340.1-2024, ISO 6507-1:2023, MOD) GB/T 9445 Qualification and Certification of Nondestructive Testing Personnel GB/T 16825.1 Inspection and calibration of static uniaxial testing machines for metallic materials - Part 1: Tensile and/or compressive testing machines Inspection and calibration of force measurement systems (GB/T 16825.1-2022, ISO 7500-1:2018, IDT)

3 Terms and Definitions

The following terms and definitions apply to this document.

process supplier

A company that provides rail welding processes, related equipment, consumables and tools.

production

To enable rail transit operations, rail welding work is carried out at the rail welding base/railway track site.