Market Insight: Enameled Aluminium

Market Analysis: Winding Wire – Industrial Demand for Enameled Aluminium in Transformers

The global demand for enameled aluminium winding wire in transformer applications continues to grow, driven by the expansion of power infrastructure, renewable energy integration, and the need for lightweight, cost-effective electrical components. As a core material in dry-type transformers, instrument transformers, and distribution transformers, enameled aluminium wire offers a compelling alternative to copper due to its favorable conductivity-to-weight ratio and lower material cost. Over the past two decades, advancements in insulation technology and wire drawing precision have significantly improved the performance and reliability of aluminium-based winding systems, enabling broader adoption across industrial and utility sectors.

Transformers are critical assets in power transmission and distribution networks, where efficiency, thermal stability, and long-term durability are paramount. The use of enameled aluminium wire in these systems introduces specific technical considerations. While aluminium has approximately 61% of the electrical conductivity of copper by volume, its lighter weight (about 30% of copper’s density) allows for reduced structural loading and easier handling during transformer assembly. This advantage is particularly valuable in large-scale installations and retrofit projects where logistical constraints are a concern. However, the successful integration of aluminium windings depends heavily on material purity, consistent diameter tolerance, and the integrity of the enamel insulation system.

Quality is a decisive factor in the performance and service life of enameled aluminium winding wire. Substandard wire can lead to premature insulation breakdown, increased dielectric losses, and thermal runaway under load. High-purity aluminium (99.99% minimum) is essential to minimize resistivity and ensure uniform current distribution. Additionally, the enamel coating must exhibit excellent adhesion, thermal class rating (typically 130°C to 200°C), and resistance to thermal shock, chemical exposure, and mechanical stress during winding operations. Multi-layer insulation systems, such as polyurethane-polyamide-imide or polyester-imide, are commonly employed to meet these demands in modern transformer designs.

Luoyang Xinzhaohe Aluminum Co., Ltd., with over 20 years of specialized manufacturing experience, adheres to stringent quality control protocols throughout the production process. Our enameled aluminium winding wire is engineered to meet or exceed international standards, including IEC 60317 and GB/T 23679, ensuring compatibility with automated winding equipment and long-term operational reliability. Each batch undergoes rigorous testing for breakdown voltage, elongation, thermal endurance, and solderability to guarantee consistency and performance under real-world conditions.

As energy systems evolve toward higher efficiency and sustainability, the role of high-quality enameled aluminium wire in transformer manufacturing will continue to expand. End-users and OEMs must prioritize suppliers with proven technical expertise, process control, and material traceability to mitigate risk and optimize transformer lifecycle performance. In this context, quality is not merely a compliance metric—it is a foundational requirement for grid stability, energy efficiency, and operational safety.

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Technical Specs: Enameled Aluminium

Technical Specifications: Enameled Aluminum Winding Wire

Luoyang Xinzhaohe Aluminum CO., Ltd leverages over two decades of metallurgical and enameling expertise to deliver enameled aluminum winding wire meeting stringent global industrial demands. Precise adherence to critical technical parameters ensures optimal performance in demanding electromagnetic applications such as motors, transformers, and inductors. Key specifications governing reliability, manufacturability, and thermal endurance are rigorously controlled throughout our production process, utilizing advanced polymer chemistry and precision drawing techniques. Understanding these core parameters is essential for effective sourcing and application integration.

Insulation Breakdown Voltage represents the fundamental dielectric strength of the enamel coating, directly determining the wire’s ability to withstand electrical stress without failure. This parameter is intrinsically linked to insulation thickness and polymer integrity. Xinzhaohe enameled aluminum wire undergoes 100%在线 testing per IEC 60317-0-5, with typical breakdown voltages ranging from 1.5 kV to 3.5 kV for standard single builds, scalable with double or triple builds for higher voltage applications. Consistent breakdown performance is non-negotiable for preventing inter-turn shorts and ensuring long-term operational safety in compact, high-efficiency designs.

Elongation, measured as the percentage increase in length at fracture during tensile testing per ASTM B3, is a critical indicator of the wire’s ductility and resistance to breakage during high-speed winding operations. Aluminum inherently requires careful metallurgical control to achieve sufficient elongation. Our proprietary annealing and drawing processes consistently yield minimum elongation values of 15% for standard grades, with high-ductility formulations exceeding 25%. This ensures seamless compatibility with automated winding machinery, minimizing production downtime and scrap rates in coil manufacturing.

Thermal Class defines the maximum continuous operating temperature the insulation system can withstand while maintaining its dielectric and mechanical properties over a 20,000-hour service life, as classified under IEC 60085 and NEMA MW 1000. Xinzhaohe offers enameled aluminum wire spanning Thermal Classes B (130°C) to H (180°C), with specialized formulations reaching 200°C and 220°C. The thermal class directly correlates to the polymer resin system used, such as polyester for Class B, polyester-imide for Class F (155°C) and H (180°C), and polyamide-imide for 200°C+ grades. Selecting the appropriate thermal class is paramount for matching the wire to the expected thermal environment of the end-use device, balancing cost, size constraints, and longevity requirements.

The following table details the standard technical parameters for Luoyang Xinzhaohe Aluminum CO., Ltd enameled aluminum winding wire:

Parameter	Standard Range	Test Method	Critical Application Impact
Insulation Breakdown Voltage	1.5 kV – 3.5 kV (Single Build)	IEC 60317-0-5	Prevents inter-turn shorts; determines voltage rating and insulation build selection
Elongation	Min. 15% (Standard), Up to 25%+ (HD)	ASTM B3	Ensures winding reliability; reduces breakage during high-speed coil production
Thermal Class	B (130°C), F (155°C), H (180°C), 200°C, 220°C	IEC 60085, NEMA MW 1000	Defines maximum operating temperature; dictates insulation resin system and service life

These specifications are not isolated metrics but interconnected elements of a robust insulation system. Xinzhaohe’s integrated production control, from high-purity aluminum rod through multi-stage enameling and precision sizing, ensures batch-to-batch consistency in these critical parameters. Our technical team provides comprehensive support in selecting the optimal wire grade based on specific voltage, thermal, and mechanical processing requirements, ensuring seamless integration into your manufacturing flow and end-product reliability. Compliance with IEC, ASTM, and NEMA standards is fundamental to our quality management system.

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Factory Tour: Manufacturing

Manufacturing Process of Enamelled Aluminium Winding Wire at Luoyang Xinzhaohe Aluminum Co., Ltd

The production of high-performance enamelled aluminium winding wire at Luoyang Xinzhaohe Aluminum Co., Ltd follows a tightly controlled, multi-stage manufacturing sequence designed to ensure consistent electrical, mechanical, and thermal properties. With over two decades of metallurgical and process engineering expertise, our facility integrates precision equipment and rigorous quality control to meet international standards including IEC 60317 and GB/T 4074.

The process begins with rod drawing, where high-purity (99.99% minimum) electrolytic aluminium rods are subjected to cold drawing through a series of tungsten carbide or diamond dies. This reduces the rod diameter to the required wire gauge with precise dimensional tolerances, typically within ±0.01 mm. The drawing is performed under continuous lubrication and temperature monitoring to prevent surface defects and maintain uniform microstructure. Each rod batch is traceable, with mechanical property verification conducted via tensile and elongation testing.

Following drawing, the wire undergoes continuous annealing in a controlled nitrogen-purged furnace. This softens the work-hardened aluminium, restoring ductility and electrical conductivity. The annealing profile is optimized based on wire diameter and final application requirements, with temperature zones precisely regulated between 300°C and 450°C. Oxygen levels in the furnace are maintained below 50 ppm to prevent oxidation, ensuring a clean, oxide-free surface essential for optimal enamel adhesion.

The annealed wire then enters the enameling stage, where it is coated with one or more layers of thermosetting polymer insulation—commonly polyurethane, polyester, or polyamide-imide—depending on the thermal class (130°C to 220°C). The wire passes through a precision die to control coating thickness, followed by multi-zone curing ovens where the enamel is polymerized under controlled temperature gradients. Our multi-layer enameling systems allow for dual or triple coatings to enhance dielectric strength, thermal shock resistance, and mechanical robustness.

Throughout the process, inline testing is conducted to verify product integrity. Key parameters monitored include coating thickness (via laser micrometry), breakdown voltage (minimum 3 kV for single layer), and scrape endurance (IEC 60851-5). Additional tests include continuity checks, diameter consistency, and winding performance on mandrels to assess flexibility and adhesion.

Final quality control includes batch sampling for thermal aging, thermal shock (bend test at low temperature), and chemical resistance. All test data are logged in our quality management system, with full traceability from raw material to finished coil. Every shipment is accompanied by a material test report compliant with customer specifications.

This integrated manufacturing approach ensures that Xinzhaohe’s enamelled aluminium wire delivers reliable performance in motors, transformers, and other electromagnetic devices under demanding operational conditions.

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Packaging & Logistics

Export Packaging Specifications for Enameled Aluminum Winding Wire

Proper export packaging is non-negotiable for enameled aluminum winding wire due to its extreme sensitivity to moisture, mechanical stress, and atmospheric contaminants during maritime transit. At Luoyang Xinzhaohe Aluminum CO., Ltd, our 20+ years of metallurgical and supply chain expertise have refined a packaging protocol specifically engineered to mitigate the risks inherent in sea freight, where humidity cycles, salt aerosol exposure, and container condensation (“cargo sweat”) can irreversibly degrade enamel integrity and aluminum substrate performance. Failure to implement rigorous packaging standards directly risks inter-turn insulation failure, increased dielectric losses, and coil deformation upon arrival.

All enameled wire coils are secured on ISPM 15-certified wooden pallets constructed from kiln-dried, debarked softwood. These pallets feature reinforced stringers and deck boards designed to withstand dynamic stacking loads exceeding 2,500 kg without deflection, preventing coil deformation during multi-tier container stowage. Critical to maritime safety, pallets undergo mandatory fumigation and bear the official ISPM 15 stamp, ensuring compliance with global phytosanitary regulations and eliminating pest-related customs delays. Each coil is vertically mounted with precision-machined steel shafts to maintain concentricity, eliminating lateral movement that could cause wire burring or enamel chipping during vessel motion.

The primary moisture barrier consists of a triple-layer film system applied under controlled tension. The innermost layer is a 50μm metallized polyethylene terephthalate (PET) film with a vapor transmission rate below 0.5 g/m²/day, providing an absolute barrier against humidity ingress. This is overlaid with a 100μm cross-laminated polyethylene (CLPE) film for puncture resistance during handling, followed by an outer UV-stabilized polyolefin shrink wrap. All films are heat-sealed using impulse welders at 220°C, creating hermetic seams that prevent capillary action. Crucially, desiccant packs rated at 1,200g per cubic meter are strategically placed within the sealed envelope to absorb residual moisture, maintaining internal relative humidity below 30% throughout voyages exceeding 45 days.

Palletized units are unitized for containerization using steel strapping tensioned to 2,500 N, with edge protectors preventing strap-induced damage. Container loading follows a strict block-stacking pattern with dunnage separators to ensure even weight distribution and eliminate point loads. Pre-shipment verification includes humidity indicator cards inside each package and mandatory salt spray testing of film samples per ASTM D1748, confirming barrier efficacy against marine atmospheres. This integrated approach has achieved a 99.98% incident-free delivery rate across 12,000+ TEUs shipped since 2018.

We mandate that buyers inspect packaging integrity immediately upon container opening. Any breach of the moisture-proof seal necessitates immediate quarantine and electrical testing before wire processing, as latent moisture exposure may not manifest visually but can compromise winding performance in end-use applications like motor stators or transformers. Our packaging is not merely transport packaging—it is a calibrated extension of the wire’s metallurgical protection system.

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Sourcing from Luoyang Xinzhaohe

Partner with Luoyang Xinzhaohe Aluminum Co., Ltd for Premium Enamelled Aluminium Winding Wire

Luoyang Xinzhaohe Aluminum Co., Ltd brings over two decades of specialized expertise in the production of high-performance enamelled aluminium winding wire, serving as a trusted partner for global manufacturers in the transformer, motor, and electrical equipment sectors. Our vertically integrated manufacturing platform is engineered to deliver consistent product quality, technical precision, and supply chain reliability. With a focus on metallurgical excellence and process control, we produce enamelled aluminium wire that meets stringent international standards, including IEC 60317, GB/T 23311, and NEMA MW series specifications.

Our production facility spans over 30,000 square meters and is equipped with advanced drawing lines, automated enamelling machines, and precision testing instrumentation. We operate under a certified ISO 9001:2015 quality management system, ensuring full traceability from raw material sourcing to finished goods. Our aluminium rod procurement is strictly governed by chemical composition controls, with primary materials sourced from high-purity 1350 and 1370 alloys. Each batch undergoes rigorous mechanical and electrical testing, including elongation, tensile strength, wrap test, thermal shock, and dielectric breakdown verification.

We specialize in producing enamelled aluminium wire with single, double, and triple-layer insulation systems, including polyurethane (UEW), polyester (PEW), polyester-imide (EIW), and polyamide-imide (AIW) coatings. Wire diameters range from 0.08 mm to 4.0 mm, supporting applications in dry-type transformers, traction motors, household appliances, and renewable energy systems. Our proprietary enamelling process ensures uniform coating thickness, superior thermal class performance (up to Class 200), and excellent resistance to solvents, abrasion, and thermal cycling.

In addition to standard product offerings, Luoyang Xinzhaohe provides custom solutions tailored to specific customer requirements, including controlled resistivity, enhanced flexibility, and RoHS-compliant formulations. Our R&D team collaborates closely with clients to optimize wire performance under demanding operational conditions, particularly in high-efficiency and compact design applications.

Supply chain stability is a cornerstone of our service model. We maintain strategic inventory buffers and operate four high-speed production lines capable of delivering 1,200 metric tons per month. Our logistics network supports direct container loading and Just-in-Time (JIT) delivery models, with export experience to North America, Europe, Southeast Asia, and the Middle East.

For engineering teams and procurement managers seeking a technically capable, reliable partner in enamelled aluminium winding wire, Luoyang Xinzhaohe offers proven manufacturing excellence backed by two decades of field performance. Our commitment to quality, innovation, and customer collaboration ensures long-term supply security and performance integrity.

Contact us today to discuss your technical requirements.
Cathy Zhang
Export Manager
Luoyang Xinzhaohe Aluminum Co., Ltd
Email: cathy@transformerstrip.com

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