GB/T 12971.2-2023 (English Version)

Standard No.: GB/T 12971.2-2023
Language: Chinese, Available in English version
Release Date: 2023
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 12971.2-2023
Replace: GB/T 12971.2-2008

Scope: This document specifies the model, specification and representation method, technical requirements, test methods, acceptance rules, packaging and marking, storage and transportation of steel-aluminum composite contact wires for electric traction. This document is applicable to the manufacture, testing and application of steel-aluminum composite contact wires for electric traction in railways, urban transportation, industrial and mining electrical transportation and lifting systems.

Introduction

GB/T 12971.2—2023 Standard Overview

This standard is the second part of GB/T 12971 "Contact wire for electric traction", which mainly stipulates the technical requirements, test methods, acceptance rules, etc. of steel-aluminum composite contact wire for electric traction. Compared with the 2008 version, this revision adds the exposed steel CGLW104 specification and related technical requirements, and adjusts the nominal cross-sectional area of steel and aluminum of some models and specifications.

Comparison of standard frameworks

Standard content	GB/T 12971.2—2008	GB/T 12971.2—2023 (new/modified)
Model specifications	Includes CGLN and CGLW types, but does not cover exposed steel section CGLW104	Added specifications and technical requirements for exposed steel section CGLW104
Technical requirements	The nominal cross-sectional areas of steel and aluminum of some models and specifications have not been adjusted	The nominal cross-sectional area of steel and aluminum of some types of steel-aluminum composite contact wires has been changed
Test method	Straightness test and wear calculation value are not included	Added straightness requirements and wear calculation value, and optimized bonding test method

Technical background and application cases

Steel-aluminum composite contact wires are widely used in railways, urban rail transit and other fields due to their excellent conductivity and mechanical properties. With the development of electrified railways, the cross-sectional area of contact wires will change due to wear during operation, which directly affects their safety and economy.

The importance of bonding test

Bonding is an important indicator to measure the quality of steel-aluminum composite contact wires. It can be seen from the test method in Appendix D that the test of bonding strength must be carried out strictly in accordance with the standard requirements to ensure the accuracy and consistency of the test results.

Implementation suggestions

Strictly control the chemical composition of materials during the production process (see Appendix B and C) to ensure the quality of steel profiles and aluminum materials.
Strengthen surface quality inspection to avoid defects such as cracks and burrs that affect the service life of the contact wire.
For contact wires of different models and specifications, reasonably select test methods and testing equipment to ensure compliance with the requirements of the GB/T 4909 series of standards.

GB/T 12971.2-2023 Referenced Document

GB/T 12971.1-2023 Contact wires for electric traction Part 1: Copper and copper alloy contact wires
GB/T 3048.2 Test methods for electrical properties of wires and cables - Part 2: Tests for resistivity of metallic materials
GB/T 3190 Chemical composition of wrought aluminium and aluminium alloys
GB/T 4067 Testing method for electrical resistance-temperature characteristicparameters of metallic materials
GB/T 4909.2 Test methods for bare wires.Part 2:Measurement of dimensions
GB/T 4909.3 Test methods for bare wires.Part 3:Tensile test
GB/T 4909.4 Test methods for bare wires.Part 4:Torsion test
GB/T 9056-2004 Metal ruler
JB/T 8137.2 Delivery drums for wires and cables.Part 2: Wood delivery drums
JB/T 8137.4 Delivery drums for wires and cables.Part 4: Shaped steel composite delivery drums

GB/T 12971.2-2023 history

2023 GB/T 12971.2-2023 Contact wires for electric traction Part 2: Steel-aluminum composite contact wires
2008 GB/T 12971.1-2008 Trolley and contact wires for electric traction.Part 1:Copper and copper-alloy contact wires
1991 GB 12971.2-1991 Trolley and contact wires for electric traction--Part 2: Copper trolley and contact wires

GB/T 12971.2-2023