GB/T 1179

Standard Overview  

GB/T 1179 is China’s national technical standard for concentric stranded overhead conductors used in power transmission and distribution lines.  

Its full title is Round Wire Concentric Stranded Overhead Conductors. The current version is GB/T 1179-2017, replacing GB/T 1179-2008 and earlier editions. It was developed by the SAC/TC 222 (National Technical Committee on Overhead Conductors) and officially published by the Standardization Administration of China (SAC).  

Technical Specifications  

GB/T 1179 provides technical rules for concentric stranded bare conductors used in overhead power systems. It covers a comprehensive range of conductor types, from simple aluminum strands to complex steel-reinforced designs.  

Core Requirements  

• Material: Specifies requirements for raw materials (e.g., aluminum, aluminum alloy, galvanized steel, aluminum-clad steel wires), including mechanical properties and chemical composition

• Conductor Structure: Defines stranding configurations (e.g., layer arrangement, lay ratio), wire diameters, and nominal cross-sections

• Performance Parameters: Mandates mechanical properties (e.g., tensile strength, modulus of elasticity) and electrical properties (e.g., DC resistance)
• Testing: Outlines test methods for mechanical, electrical, and corrosion-resistance performance (e.g., tensile tests, torsion tests, resistivity measurements)

Key Features  

• Diverse Conductor Types: Covers all major designs, including:  
  • JL: All-aluminum conductors  
  • JLHA: Aluminum alloy conductors  
  • JL/G: Steel-reinforced aluminum conductors (ACSR)  
  • JLB: Aluminum-clad steel-reinforced conductors  
• Integrated Design: Combines high conductivity (aluminum) with mechanical strength (steel core) for optimal efficiency and reliability.  
• Strict Material Control: Mandates high-quality materials (e.g., hard-drawn aluminum, zinc-coated steel) to ensure corrosion resistance and long service life.  
• Global Alignment: Harmonizes with international standards (e.g., IEC 61089).  

Where It’s Used  

• High-voltage transmission lines (≥1 kV AC/DC) for long-distance power delivery
• Distribution networks in urban/rural grids
• Corrosive or high-load environments (e.g., coastal areas, mountainous regions)
• Critical infrastructure projects requiring high mechanical strength and electrical efficiency