Authentic Steel manufactures and supplies structural-grade medium and heavy gauge galvanized steel coils, specifically engineered to meet high load-bearing capacity, deep drawability, and long-term durability requirements. Utilizing advanced hot-dip galvanizing technology on continuous production lines, our thick-gauge GI coils deliver exceptional thickness consistency, uniform zinc adhesion, and superior structural integrity under severe mechanical stress.
Heavy gauge galvanized steel coils are the backbone of modern construction, heavy manufacturing, and industrial infrastructure. By combining robust cold-rolled or hot-rolled pickled substrates with tight zinc coating protection, these coils ensure exceptional resistance against atmospheric oxidation, mechanical wear, and structural fatigue.
Thickness Range: 0.40mm to 3.00mm ($\pm 0.02\text{mm}$ precision gauge control)
Width Availability: 914mm, 1000mm, 1200mm, 1219mm, 1250mm, 1500mm, or customized slitted strips
Zinc Coating Mass: Z30 to Z275 $\text{g/m}^2$ (Dual-sided continuous hot-dip zinc layer)
Surface Finish Options: Zero Spangle (Extra Smooth), Regular Spangle, Minimized Spangle
Substrate Mechanical Grades: Commercial Quality (CQ / SPCC / DX51D+Z), Lock-Forming Quality (LFQ / DX52D+Z), Structural Quality (S250GD, S350GD, S550GD / ASTM Grade 33, 40, 50)
Surface Post-Treatment: Chromated (Passivated), Oiled (Light/Heavy), Anti-Fingerprint (AFP), Dry
Compliance Standards: ASTM A653 / A653M, EN 10346, JIS G3302, GB/T 2518
Structural Building Framing: Formed into heavy purlins (C/Z purlins), floor decking sheets, light steel framing (LSF), and load-bearing studs for commercial buildings and warehouses.
HVAC & Industrial Ducting: Ideal for heavy-duty air duct networks, commercial ventilation systems, and industrial filter housings requiring high rigidity and corrosion resistance.
Automotive & Transportation: Processed into internal automotive reinforcement panels, chassis cross-members, trailer sideboards, and heavy shipping container flooring supports.
Highway & Municipal Infrastructure: Used for highway guardrails, noise barrier panels, cable trays, bridge drainage pipes, and power distribution cabinets.
Superior Deep Drawing & Bending Performance: Our continuous inline annealing process ensures optimal ductility, preventing zinc flaking or base metal cracking during 90-degree heavy bending, punching, or deep profiling.
Precision Slitting & Cut-to-Length Services: Equipped with heavy-duty slitting and leveling equipment, we provide customized strip widths and flat sheet lengths cut precisely to your project specifications.
Heavy-Duty Export Packaging: Every coil is wrapped with VCI anti-rust paper, protective outer steel drums, heavy corner protectors, and securely latched with high-tensile steel bands on reinforced wooden skids designed for safe ocean transport.
Q: What is the maximum zinc coating available for 3.0mm heavy gauge GI coil?
A: We offer zinc coating weights up to Z275 $\text{g/m}^2$ (or customized higher coating weights upon request) to ensure long service life in harsh outdoor environments.
Q: Can heavy gauge GI coils be used for structural C/Z purlin profiling?
A: Yes. We supply structural grades such as S350GD and S550GD with high yield strength, perfectly suited for high-speed automated purlin roll-forming machines.
