Low voltage transformers are core equipment in power distribution systems, widely used in industrial distribution, commercial buildings, residential power supply, and power electronic equipment. As the core material for low voltage transformer windings, high precision aluminum foil has thickness accuracy and surface quality directly affecting the transformer’s energy efficiency, heat dissipation, and operational reliability.
I. Technical Definition and Core Indicators of High Precision Aluminum Foil
1.1 Basic Concepts
High precision aluminum foil refers to aluminum alloy foil with thickness tolerance controlled within ±0.02mm and excellent surface quality. Compared with ordinary aluminum foil, high precision aluminum foil has the following advantages:
- Uniform thickness: Small thickness variation along the coil direction, reducing local temperature rise
- Excellent surface quality: No scratches, inclusions, oxidation defects
- High dimensional accuracy: Small width and thickness tolerances, facilitating automated winding
1.2 Core Performance Indicators
| Indicator | High Precision | Ordinary |
|---|---|---|
| Thickness Tolerance | ±0.02mm | ±0.05mm |
| Width Tolerance | ±0.3mm | ±0.5mm |
| Surface Roughness | Ra≤1.6μm | Ra≤3.2μm |
| Pinhole Count | AATCC Class 100 | No special requirement |
II. Low Voltage Transformer Requirements
2.1 Application Characteristics
Low voltage transformers (voltage level ≤1000V) have the following characteristics:
- Wide applications: Industrial, commercial, residential distribution
- Large market volume: Main products in distribution transformer market
- Cost sensitive: Intense competition requires material cost control
- High efficiency requirements: Improving energy efficiency standards
2.2 Core Selection Considerations
| Technical Points | Requirements |
|---|---|
| Thickness Accuracy | Tolerance within ±0.02mm |
| Conductivity | IACS≥59% |
| Surface Quality | Smooth, defect-free |
| Processability | Good ductility |
| Cost Effectiveness | Significant advantage over copper |
III. Technical Specifications
3.1 Recommended Grades
| Grade | Purity | Conductivity | Tensile Strength | Elongation | Application |
|---|---|---|---|---|---|
| 1060 | ≥99.60% | ≥35% IACS | 70-110 MPa | ≥15% | Standard LV Transformer |
| 1070 | ≥99.70% | ≥36% IACS | 65-100 MPa | ≥20% | High-Performance |
| 3003 | Al-Mn alloy | ≥30% IACS | 130-180 MPa | ≥8% | High Strength |
3.2 Key Performance Parameters
Electrical: Conductivity ≥34 MS/m (IACS≥59%), Resistivity ≤0.0295 Ω·mm²/m
Dimensions: Thickness 0.3-3.5mm, Tolerance ±0.02mm, Width 20-600mm
Mechanical: Tensile strength 65-180 MPa, Elongation ≥8-25%, Hardness 25-65 HV
IV. Process Matching
4.1 Winding Design Features
- Layer windings: Common layer structure, copper or aluminum foil wound
- Foil windings: High current low voltage, aluminum foil cost advantage
- Oil channel design: Inter-layer oil channels for heat dissipation
4.2 Temper Selection
| Winding Type | Temper | Elongation |
|---|---|---|
| Foil Winding | O | ≥20% |
| Cylindrical | O/H22 | ≥15% |
| High Voltage | H24/H26 | ≥12% |
4.3 Winding Parameters
Winding tension: 5-15 N/mm². Winding speed: 20-50 m/min. Annealing temperature: 300-500°C.
V. Industry Standards
Standards: IEC 60325, GB/T 8544, JIS H4160, ASTM B373
Certifications: ISO 9001, UL, RoHS/REACH, SGS
VI. Quality Inspection
| Inspection | Method | Standard |
|---|---|---|
| Thickness Tolerance | Precision Gauge | ±0.02mm |
| Thickness Uniformity | Multi-point | ≤0.02mm variation |
| Surface Quality | Visual | No defects |
| Conductivity | Eddy Current | IACS≥59% |
VII. Supplier Selection
- Full-process production line (melting → rolling → annealing → slitting)
- Thickness control accuracy: ±0.02mm
- ISO 9001/14001/45001 certified
VIII. Product Specifications
| Grade | Thickness | Width | Temper | Conductivity |
|---|---|---|---|---|
| 1060 | 0.3-3.0mm | 20-600mm | O/H22/H24 | ≥35% IACS |
| 1070 | 0.3-3.0mm | 20-600mm | O/H22/H24 | ≥36% IACS |
| 3003 | 0.5-2.5mm | 20-400mm | H24/H26 | ≥30% IACS |
Thickness Tolerance: ±0.02mm (high precision)
Conclusion
The selection of high precision aluminum foil for low voltage transformers requires focus on thickness accuracy, uniformity, and cost-effectiveness.
Our company has 30 years of experience exporting electrical wire and metal foil. We provide 1060/1070/3003 series high precision aluminum foil for low voltage transformers with customized sizes and global sample shipping.
Contact:
Email: office@cnlpzz.com
WhatsApp: 0086-19337889070
The technical parameters described are general reference values. Please consult our technical team for specific selections.