As one of China’s leading galvanized steel coil manufacturers, ChinaCNU Steel New Materials provides premium GI (Galvanized Iron) steel coils and sheets to buyers across 80+ countries. This guide covers everything you need to know before purchasing galvanized steel.
What is Galvanized Steel Coil (GI Coil)?
Galvanized steel coil is carbon steel coated with a layer of zinc through hot-dip galvanizing or electro-galvanizing process. The zinc coating provides excellent corrosion protection, significantly extending the steel’s service life in outdoor and humid environments.
GI Steel Coil Specifications
| Grade | DX51D, DX52D, DX53D, SGCC, S280GD, G550 |
| Zinc Coating | Z60, Z80, Z100, Z120, Z180, Z200, Z275, Z600 |
| Thickness | 0.12 mm – 4.0 mm |
| Width | 600 mm – 1500 mm |
| Surface | Regular spangle, zero spangle, big spangle, skin passed |
| Standard | ASTM A653, EN10327, JIS G3302, GB/T2518 |
| Certification | SGS, BV, ISO 9001:2015 |
Types of Galvanized Steel Coil
- Hot-Dip Galvanized (HDG) – Thicker zinc layer (Z80–Z600), best outdoor corrosion resistance
- Electro Galvanized (EG) – Thin, uniform zinc layer, superior surface for painting
- Zero Spangle – Smooth surface, ideal for painting and forming
- Big Spangle – Decorative zinc flower, popular for roofing and fencing
Key Applications
- 🏗️ Construction – Roofing sheets, wall panels, purlins, steel framing
- 🚗 Automotive – Body panels, structural components
- 🏠 Home Appliances – Washing machine drums, refrigerator backs
- 🌾 Agriculture – Grain silos, irrigation equipment
- ⚡ Electrical – Cable trays, conduits, enclosures
- 🏭 Industrial – Storage shelves, machine housings
How to Choose the Right Zinc Coating Weight?
- Z60–Z80: Indoor applications, low humidity environments
- Z100–Z120: General outdoor use, moderate exposure
- Z180–Z200: Roofing, moderate corrosive environments
- Z275+: Coastal areas, high humidity, harsh industrial environments
Request a Free GI Steel Coil Quote
Send us your specifications — grade, zinc coating, thickness, width, quantity — and our team will reply within 24 hours with the best factory price (FOB Tianjin/Qingdao).
📧 Email: chinacnu01@gmail.com
🌐 Website: https://chinacnu.com
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