Hot dipped galvanized steel coil (GI steel coil) is a corrosion-resistant coated steel product manufactured by continuously immersing cold rolled or hot rolled steel substrate into molten zinc. The zinc coating forms a protective barrier on the steel surface, significantly improving durability and service life in humid and outdoor environments.

Galvanized steel coils are available in multiple zinc coating levels such as Z80, Z120, Z180, and Z275, with regular spangle, minimized spangle, or zero spangle surface finishes to meet different industrial requirements.

Our galvanized steel products comply with international standards including EN 10346, ASTM A653, and JIS G3302, and are widely used in roofing systems, steel structures, home appliances, HVAC systems, transportation equipment, and industrial fabrication.

Compared with ordinary carbon steel, GI steel coil offers better corrosion resistance, improved processing performance, lower maintenance costs, and higher economic efficiency.

Traditional steel materials are highly susceptible to oxidation and corrosion when exposed to moisture, oxygen, acid rain, or industrial pollutants.

In applications such as roofing panels, wall cladding, ventilation systems, and household appliances, untreated steel may suffer from:

• Surface rust and white corrosion
• Reduced structural strength
• Shortened product lifespan
• Increased maintenance and replacement costs
• Poor appearance after long-term exposure

Industries such as construction, automotive, appliance manufacturing, and infrastructure require durable steel materials with long-term anti-corrosion protection and stable surface quality.

Hot dip galvanized steel coil solves corrosion problems by coating steel with a protective zinc layer through a continuous galvanizing process.

The zinc coating provides dual protection:

The zinc layer isolates steel from air and moisture, slowing oxidation.

Even if scratches occur, zinc corrodes first and protects the steel substrate from rust.

Different steel grades and coating weights can be selected according to application requirements:

• DX51D+Z → General forming and construction applications
• DX53D+Z → Deep drawing and stamping applications

Higher zinc coating weights such as Z180 and Z275 provide stronger corrosion resistance for outdoor and coastal environments.

Galvanized steel coil is widely used across multiple industries because of its excellent corrosion resistance and processing flexibility.

• Roofing sheets
• Wall cladding panels
• Steel structure buildings
• Ceiling systems

• Refrigerator panels
• Washing machine shells
• Air conditioner housings

• Structural reinforcements
• Highway guardrails
• Vehicle internal parts

• Ventilation ducts
• Cable trays
• Electrical cabinets
• Storage racks

The hot dip galvanizing process involves immersing cleaned steel substrate into molten zinc at high temperature.

During this process:

1. The steel reacts with molten zinc
2. Zinc-iron alloy layers form on the surface
3. A pure zinc outer layer provides corrosion protection

This coating system protects steel through:

Preventing direct contact between steel and external moisture.

The zinc layer corrodes first, protecting exposed steel from rust even when scratched.

This dual-protection mechanism allows galvanized steel to maintain long-term durability in outdoor and industrial environments.

Selecting the correct galvanized steel coil depends on environment, processing requirements, and service life expectations.

To ensure the product arrives in perfect condition:

• Inner Packaging: Anti-rust oil film + water-proof kraft paper
• Outer Packaging: Galvanized steel sheet wrapping + iron rings reinforcement
• Loading: Standard export sea-worthy packaging

Port of Loading: Tianjin / Shanghai / Qingdao, China

Delivery Time: 15-25 days after receiving deposit or LC

Galvanized steel coil is steel coated with zinc through a hot-dip galvanizing process to improve corrosion resistance.

Z275 means the total zinc coating weight is 275 g/m², offering stronger corrosion protection than lower coating levels.

DX53D+Z provides better elongation and deep drawing performance, while DX51D+Z is suitable for general forming applications.

Z120, Z180, and Z275 are commonly recommended for roofing sheets depending on environmental conditions.

GI uses pure zinc coating, while GL (Galvalume Steel) uses aluminum-zinc alloy coating with better corrosion resistance and heat reflectivity.