Galvanized Steel Coil Carbon Steel — Factory Direct Supplier | Huaxia-Steel
Hot-dip galvanized steel coil (GI coil) is carbon steel strip continuously coated with zinc for long-life corrosion protection. It is the raw material behind roofing and cladding panels, ducting, purlins, appliance shells, and roll-formed profiles. Huaxia-Steel supplies galvanized steel coil in widths from 600 to 1,500 mm and thicknesses from 0.12 to 4.0 mm, with zinc coatings from Z40 to Z275 g/m² and regular, minimized, or zero spangle finishes, produced to ASTM A653, EN 10346, and JIS G3302.
Product Overview
Our galvanized coils are produced on continuous hot-dip galvanizing lines: cold-rolled substrate is cleaned, annealed in-line, dipped in a molten zinc (or zinc-aluminum) bath, wiped to the target coating weight, and skin-passed for surface and mechanical finish. We supply full hard, half hard, and soft (drawing quality) tempers to match downstream roll forming, folding, or deep drawing. Coils can be supplied mill-edge or slit to width, oiled or passivated, and cut to sheet or corrugated on request.
Specifications
| Parameter | Details |
|---|---|
| Thickness | 0.12 – 4.0 mm (tolerance per EN 10143 / ASTM A924) |
| Width | 600 – 1,500 mm; slit coils from 20 mm |
| Coil weight | 3 – 10 tons; custom coil OD on request |
| Base steel | Commercial steel (CS), forming steel (FS/DS), structural S250–S550 |
| Standards | ASTM A653 CS/FS/SS Gr 33–80; EN 10346 DX51D+Z, S250GD–S550GD+Z; JIS G3302 SGCC/SGCH |
| Zinc coating | Z40 – Z275 g/m² (total both sides); Z600+ for special order |
| Spangle | Regular, minimized, zero spangle |
| Surface treatment | Chromated/passivated, oiled, anti-finger print on request |
| Tempers | Full hard, half hard, soft / drawing quality |
Zinc Coating Selection Guide
| Coating (g/m²) | Approx. zinc layer (µm/side) | Typical service |
|---|---|---|
| Z40–Z60 | 3–5 | Indoor ducts, furniture, appliance inner panels |
| Z100–Z140 | 8–12 | General construction, purlins, light profiles |
| Z180–Z275 | 14–20 | Roofing, cladding, outdoor exposure |
| Z350–Z600 | 26–45 | Marine/coastal, severe environments, agricultural buildings |
As a rule of thumb, doubling the zinc mass roughly doubles the time to first rust in a given environment. For coastal or industrial atmospheres, specify Z275 minimum and consider paint or zinc-aluminum (Galvalume-type) coating for extended life.
Available Grades
Manufacturing Standards and Quality Control
Production follows ISO 9001-controlled galvanizing lines. Incoming substrate is checked for chemistry and thickness; the line continuously monitors bath temperature (typically 450–460°C), line speed, and air-knife pressure which set the coating weight. Finished coil is tested for coating mass (double-side gravimetric or X-ray), adhesion (bend/impact test), spangle classification, and mechanical properties.
Applications
Packaging and Shipping
Coils are eye-to-sky or eye-to-wall packed on wooden or steel pallets per ISPM 15, wrapped with VCI paper, waterproof film, and galvanized steel banding. Ends are protected with inner and outer protection rings. We ship 20-ton optimized loads in 20 ft containers or full coils by bulk; FOB, CFR, CIF, and DAP terms available.
Get a mill-direct galvanized coil quotation
Send thickness, width, zinc coating, standard, and tonnage. Huaxia-Steel returns a competitive factory price with MTC and lead time. Request a quote.
