Authentic Steel manufactures and exports high-grade regular and big spangle galvanized steel coils (traditional spangled GI coils) featuring distinct, aesthetically appealing zinc crystal flower patterns. Produced through a controlled hot-dip galvanizing process, molten zinc crystallizes naturally on the cold-rolled steel substrate during cooling, forming vibrant spangles that give the steel its classic metallic appearance and long-lasting sacrificial corrosion protection.
Regular and big spangle galvanized coils are globally recognized for their durability, economical value, and excellent resistance to atmospheric oxidation. The natural zinc crystal structure provides a robust surface shield, making these coils particularly popular in outdoor construction, agricultural framing, and general metal fabrication where unpainted visual appeal and raw weatherability are desired.
Surface Finish Options: Regular Spangle (Normal Spangle), Big Spangle (Large Visible Zinc Flowers), Minimized Spangle
Thickness Range: 0.12mm to 3.00mm ($\pm 0.015\text{mm}$ precision tolerance control)
Width Availability: 600mm, 752mm, 914mm, 1000mm, 1200mm, 1219mm, 1250mm, or customized slitted narrow strips
Zinc Coating Mass: Z30 to Z275 $\text{g/m}^2$ (Dual-sided continuous hot-dip zinc layer)
Substrate Mechanical Grades: Commercial Quality (CQ / SPCC / DX51D+Z), Full Hard Quality (FH / HRB > 85), Structural Quality (S250GD+Z, S350GD+Z / ASTM Grade 33, 40, 50)
Surface Passivation & Protection: Chromated Passivation (Anti-White Rust), Oiled, Anti-Fingerprint (AFP), Dry
Compliance Standards: ASTM A653 / A653M, EN 10346, JIS G3302, GB/T 2518
Roofing Sheets & Wall Cladding: Processed into classic corrugated sheets, trapezoidal roof panels, and exterior wall siding across Southeast Asia, Africa, Latin America, and the Middle East.
Agricultural Storage & Infrastructure: Widely used in grain silo walls, livestock shed cladding, water storage tank shells, and agricultural enclosure framing.
HVAC & General Sheet Metal Fabrication: Formed into air conditioning ductwork, ventilation channels, cable trays, and rainwater gutters.
Structural Hardware & Enclosures: Ideal for electrical junction boxes, outdoor cabinet covers, highway guardrail components, and temporary site fencing.
Vibrant & Uniform Spangle Control: Advanced air-knife and solidification cooling management ensure uniform spangle distribution and bright metallic luster across the entire coil surface.
Strong Sacrificial Corrosion Shield: The multi-layered zinc-iron alloy barrier provides self-healing galvanic protection at cut edges and punched holes, ensuring extended service life in humid climates.
Export-Grade Heavy Packaging: Wrapped with VCI anti-rust paper, waterproof inner plastic sheeting, heavy outer steel drums, and reinforced wooden skids to prevent white rust formation during ocean transit.
