Steel Core Aluminum Conductor JKLGYJ Overhead Line Cable for Power Grid Distribution

JKLGYJ is a professional medium-voltage steel-cored aluminum stranded overhead insulated cable, specifically developed for outdoor overhead power transmission and distribution systems. It employs a steel-reinforced aluminum conductor and cross-linked polyethylene (XLPE) insulation structure, perfectly combining excellent mechanical tensile properties, low power loss electrical performance, superior weather resistance, and safe insulation protection.

Unlike ordinary bare overhead conductors and ordinary low-voltage insulated cables, JKLGYJ cables are specifically designed for long-span laying, complex climatic environments, grid load stability, and long-term operational safety. They effectively address points faced by engineers and global procurement personnel, such as line sag, wind and ice damage, partial discharge, high maintenance costs, and short service life. These cables are widely applicable to national power grid upgrades and renovations, industrial park power supply, new energy grid connection, and overhead power projects in mountainous and coastal areas worldwide. Fully compliant with international and national authoritative industry standards, they are the preferred medium-voltage overhead transmission solution for global power engineering contractors, grid operators, and EPC companies.

• IEC 60840: Extruded Insulated Power Cables with Rated Voltages from 3.6 kV to 36 kV
• IEC 60287: Standard for Calculating Rated Current of Cables
• CE Certification: Compliant with EU Low Voltage Directive and Electromagnetic Compatibility Requirements
• RoHS: Environmental Restriction of Hazardous Substances
• ISO 9001: Quality Management System Certification
• ISO 14001: Environmental Management System Certification

• GB/T 14049-2008: Overhead Insulated Cables with Rated Voltage of 10kV and Below
• GB/T 1179: Round Wire Concentric Stranded Conductors for Overhead Lines
• GB/T 12706: Rated Voltage Extruded Insulated Power Cables and Accessories
• DL/T 5221: Technical Specification for Design of Overhead Distribution Lines

It complies with global power grid construction standards, overhead line sag and tension design standards, wind load and ice load design standards, coastal salt spray corrosion prevention engineering standards, and renewable energy power plant grid connection technical standards.

5. Core Application Scenarios and Practical Engineering Cases

• Urban and rural medium-voltage power grid upgrades and overhead trunk line laying
• Photovoltaic power stations and wind farm grid-connected transmission lines
• Medium-voltage power supply lines for industrial parks, chemical plants, mining areas, and logistics parks
• Large-span overhead transmission projects in mountainous, hilly, and forested areas
• Distribution lines in coastal areas with salt spray, high humidity, and strong ultraviolet radiation
• Overhead transmission lines for railways, highways, and municipal infrastructure
• Power supply projects for remote islands and large-span overhead lines across rivers

African National Power Grid Upgrade Project: The rural overhead distribution network upgrade adopted JKLGYJ 26/35kV cables. Their high tensile strength adapts to the local strong winds and high temperatures. Optimized long-span laying reduces the number of towers, effectively lowering the total project investment. The lines have operated stably and without faults for many years.

South American Wind Farm Grid Connection Project: The wind farm's outgoing lines use JKLGYJ medium-voltage overhead cables. XLPE insulation is resistant to strong ultraviolet radiation and alternating temperature differences, resulting in low line loss, improved transmission efficiency, and full compliance with local IEC grid connection standards. The project has also passed third-party engineering acceptance.

Southeast Asian Coastal City Power Distribution Projects: The salt spray and high humidity environment of coastal areas place high demands on the corrosion resistance and insulation stability of cables. JKLGYJ's special weather-resistant insulation formula avoids surface tracking and discharge, solving the problems of easy aging and failure of ordinary cables in coastal areas, and reducing the frequency of later maintenance.

Domestic Mountainous Long-Span Overhead Projects: For overhead laying across valleys in mountainous areas, steel core reinforcement significantly improves tensile strength, controls line sag within the allowable range, adapts to winter snow and ice loads, and ensures the reliability of power supply in complex terrain.

• Superior Mechanical Properties: The built-in steel core significantly enhances overall tensile strength, making it suitable for long-span laying, effectively controlling line sag, reducing the number of support towers, and saving on engineering infrastructure costs. Compared with pure aluminum overhead cables, it has stronger resistance to wind, ice, and external mechanical damage.
• Stable Electrical Performance and Low Line Loss: Optimized conductor stranding process reduces DC resistance; high-purity cross-linked polyethylene (XLPE) insulation features low dielectric loss, high breakdown field strength, and extremely low partial discharge rate. Even under long-term full-load operation, it maintains stable transmission efficiency, reduces power loss, and improves the economic efficiency of the power grid.
• Extreme Weather Resistance: Utilizing a specially modified cross-linked polyethylene (XLPE) insulation formula, it possesses resistance to ultraviolet radiation, ozone, aging, and salt spray corrosion. It can withstand extreme temperatures ranging from -40℃ to +50℃, high humidity, strong winds, ice and snow, and harsh environments such as coastal salt spray, without easily cracking, aging, or leakage.
• High Safety and Low Maintenance Costs: The overhead insulation design avoids the hazards of short circuits and electric shocks caused by tree branches, greatly improving the safety of lines in densely populated areas and forested regions. Excellent leakage and surge resistance results in a low failure rate, significantly reducing subsequent inspection and maintenance costs.
• Standardized yet customizable: Fully implements authoritative international and domestic standards and provides complete technical specifications. Supports customization of parameters such as conductor cross-section, insulation thickness, and steel core ratio based on project span, load current, and environmental conditions to meet engineers' personalized engineering design needs.

• Strict Standards and Compliance & Comprehensive Testing: All products are manufactured according to industry standards such as IEC, GB, and DL, and raw materials undergo rigorous selection. Finished products pass partial discharge testing, withstand voltage testing, tensile strength testing, and insulation resistance aging testing, with authoritative third-party testing reports provided.
• Professional Engineering Support: We offer free technical services, including cable current carrying capacity calculation, sag calculation, laying scheme design, and model selection recommendations. Our professional engineering team supports EPC project bidding and provides standard parameter tables and CAD drawings.
• Global Project Delivery & Accessories: Standard export steel and wood reel packaging, suitable for long-distance sea and land transportation. We support bulk orders and customized production, providing a complete set of overhead hardware and connectors, offering buyers a one-stop procurement service.
• Low total cost of ownership: Reasonable direct-from-the-factory prices; long service life, low line loss, low infrastructure investment, and extremely low maintenance costs. From initial procurement to long-term operation, comprehensively reducing the total cost of ownership for global buyers and engineering projects.

• The cable type should be selected to match the rated voltage, actual load current, and laying span. For long-span projects, current-carrying capacity and sag tension must be calculated in advance.
• In coastal areas, chemical environments, and salt spray environments, weather-resistant reinforced JKLGYJ cables should be prioritized, along with matching corrosion-resistant hardware.
• Construction should meet minimum bending radius requirements, avoiding severe bending and compression to prevent insulation damage and the risk of hidden partial discharge.
• The ambient temperature during construction should not be lower than -20°C. In areas with significant temperature differences, expansion margins should be allowed to prevent excessive sag or tension overload.
• All support fittings, clamps, and connectors should be compatible with cable specifications and conductor materials to avoid galvanic corrosion and contact overheating failure.