Hot dipped galvanized steel coil
The galvanized coils is defined as a carbon steel sheet coated with zinc on both sides. A zinc coating is one of the most effective and economical methods of protecting bare steel from a corroding environment. The zinc not only serves as a barrier between the steel and the environment, but it will also sacrifice itself to protect the underlying steel sheet.
Spangle：Galvanization or galvanizing is the process of applying a protective zinc coating to steel or iron, to prevent rusting. The size of crystallites (grains) in galvanized coatings is a visible and aesthetic feature, known as “spangle”.
Zinc Coated：With the cold-rolled steel of different strengths and thickness as substrate. it is produced by applying the zine coat on both faces by hot-dip process.
Width :≤1250mm
Thickness: 0.12mm~1.2mm
Zinc Coating: 40~275gram/㎡
Surface Treatment：Passivation/oiling
Spangle Types：Zero/ small/ regular/ big spangle
Weight Varies By Profile
Galvanized steel coil, immersing the thin steel plate in the molten zinc bath, and adhering a layer of zinc thin steel plate on the surface.
It is mainly produced by the continuous galvanizing process, that is, the coiled steel plate is continuously immersed in the zinc-melted plating tank to make galvanized steel plate; alloyed galvanized steel plate.
This kind of steel plate is also made by the hot-dip method, but it is heated to about 500 °C immediately after exiting the tank to form an alloy film of zinc and iron. This galvanized steel coil has good paint adhesion and weldability.
Widely used in construction, light industry and other industries.
Our MOQ is usually 1x20ft container.Free sample is ok but need pay the courier charge.Charge can be dedubt in future orders.
Commercial
Industrial
Precision-engineered for superior performance, our GI coils combine unmatched durability with exceptional surface quality. Utilizing advanced continuous hot-dip galvanizing technology, we produce coils with zinc coatings ranging from 0.12mm to 1.2mm, ensuring optimal corrosion resistance for even the most demanding applications.
Our galvanized steel coils are manufactured according to international standards such as ASTM A653, JIS G3302, and EN 10346.
| Item | Specification |
|---|---|
| Product | GI Coil / Galvanized Steel Coil |
| Standard | ASTM A653 / JIS G3302 / EN 10346 |
| Base Material | Cold Rolled Steel / Hot Rolled Pickled Steel |
| Thickness | 0.12 – 3.0 mm (Custom up to 6.0 mm) |
| Width | 600 – 1250 mm |
| Coil Weight | 3 – 20 Tons |
| Inner Diameter | 508 mm / 610 mm |
| Zinc Coating | Z30 – Z275 (30–275 g/m²) |
| Surface Type | Regular Spangle / Zero Spangle / Minimized Spangle |
| Surface Treatment | Chromated / Oiled / Dry / Anti-fingerprint |
| Steel Grade | DX51D, DX52D, DX53D, SGCC, S250GD–S550GD |
| Application | Roofing, Wall Cladding, HVAC, Automotive, Appliances |
Our GI coils are produced using continuous hot-dip galvanizing (HDG) technology. The steel strip is passed through a molten zinc bath at approximately 450°C, forming a metallurgical bond between zinc and steel.
Cold Rolled Steel → Cleaning → Annealing → Zinc Bath → Air Knife Control → Cooling → Skin Pass → Surface Treatment → Coiling
Zinc coating weight is one of the most important factors affecting corrosion resistance.
Higher coating weight = longer protection life.
Galvanized steel coils offer excellent balance of strength and formability:
Suitable for stamping, bending, roll forming, and structural fabrication.
Zinc coating provides sacrificial protection, extending material lifespan significantly.
Compared to stainless steel, GI coil offers lower cost while maintaining durability.
Suitable for bending, stamping, roll forming, and welding.
Used in construction, automotive, appliances, and infrastructure.
GI coils are widely used across multiple industries:
| Material | Corrosion Resistance | Cost | Main Application | Service Life |
|---|---|---|---|---|
| GI Coil | High | Medium | Construction / Industrial | 10–30 Years |
| Cold Rolled Steel (CRC) | Low | Low | Indoor Products | 3–8 Years |
| Galvalume Steel (GL) | Very High | Higher | Coastal Roofing | 20–40 Years |
| PPGI Coil | High + Decorative | Higher | Decorative Buildings | 15–30 Years |
We ensure strict quality control:
For procurement and engineering projects, consider:
Galvanized steel coils are one of the most widely used steel materials in global industry. With excellent corrosion resistance, formability, and cost efficiency, GI coils are the ideal choice for construction and manufacturing industries.
As a reliable China GI coil manufacturer, we provide stable quality, competitive pricing, and global supply capability.
A: Construction, roofing, automotive, and industrial manufacturing.
A: It means 275 g/m² zinc coating for high corrosion resistance.
A: GI is zinc-coated steel; PPGI is pre-painted galvanized steel.
A: MOQ depends on specification, usually 10–25 tons.
A: Yes, samples can be provided for quality evaluation.
A: Typically 15–30 days depending on order volume.
A: Yes, customized specifications are available.
We appreciate your interest in our factory. If you have any questions or require further information about our customizable GI coil colors or any other aspect of our products and services, please do not hesitate to contact us. We look forward to the opportunity of working with you and delivering exceptional results.
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