Home  >  Industry News

What Is Galvanized Steel Coil? GI Steel Coil?

Apr. 13, 2024

What is galvanized steel coil?


Galvanized steel coil is a product that has undergone a galvanization process to protect it from corrosion. This process involves coating the steel with a layer of zinc, which creates a barrier against moisture and other corrosive elements. The galvanization process enhances the steel's durability, making it ideal for outdoor applications and industries such as construction, automotive, and agriculture.


Galvanized steel coil and GI steel coil refer to the same product, which is cold rolled steel sheet coated with zinc. It is also known as galvanized iron or GI.


Galvanized Steel Coils

Galvanized steel coil is produced by passing cold rolled steel sheet through a molten zinc bath. The zinc coating acts as a protective barrier between the steel and the environment, providing corrosion resistance. Galvanized steel coil is widely used in applications that demand rust prevention and prolonged durability, including:


- Building and construction: Galvanized steel coil is widely used in roofing, siding, gutters, decking, and other construction applications. Its zinc coating offers protection against rusting, even in harsh outdoor conditions.

- Vehicle components: Galvanized steel coil is used for manufacturing vehicle panels, chassis parts, wheels, and other automotive components due to its impact resistance and rust prevention properties.

- Appliances: It provides sturdy support and rust protection for appliances like refrigerators, washing machines, and ovens.

- Storage systems: Galvanized steel coil is ideal for shelving, containers, cabinets, and other storage systems, offering durability for long-term use indoors and outdoors.

- Infrastructure: Lamp posts, railings, bollards, and other infrastructure components benefit from galvanized steel's resistance to corrosion, even in moist, chemical, and polluted environments.


Galvanized steel coil is characterized by a protective zinc coating applied at a controlled thickness, combining the strength of steel with the corrosion resistance of zinc. With a lifespan of 20-30 years, it typically maintains its integrity without significant peeling or cracking. The performance and durability of galvanized steel coil depend on factors such as the thickness, uniformity, and adhesion of the zinc coating.


As a versatile and cost-effective building material, galvanized steel coil finds extensive use. However, its zinc coating thickness poses challenges for painting applications. For those seeking color customization, options include pre-painted galvanized steel or alternative corrosion-resistant materials such as aluminum.


Galvanized steel coil types


There are essentially two types of galvanized steel coils based on the zinc coating process:


Hot-Dip Galvanized Steel Coils: This is the most popular and commonly utilized form of galvanized steel coils. During the hot-dip galvanizing process, steel coils are immersed in a bath of molten zinc, establishing a metallurgical bond with the steel surface. The result is a thick and long-lasting zinc coating with exceptional corrosion resistance. Hot-dip galvanized steel coils are renowned for their rust-resistant properties and find widespread use across various industries.


Electro-Galvanized Steel Coils: In the electro-galvanizing process, a thin layer of zinc is applied to steel coils through electrolysis. Unlike hot-dip galvanizing, electro-galvanizing does not involve immersion in molten zinc. Electro-galvanized steel coils have a thinner zinc coating compared to hot-dip galvanized coils. They offer modest corrosion resistance and are often used in applications where a lighter coating is sufficient or where a smooth and consistent appearance is desired.


Both types of GI steel coils have their own advantages and are suitable for diverse applications, depending on the level of corrosion resistance required and specific project needs.


Why Choose Galvanized Steel Coil?


1. Cost-effective Solution

When considering cost-effectiveness, galvanized coil stands out as the most economical option compared to GL or color-coated steel coils, offering similar features such as excellent corrosion resistance and a pleasing appearance.


2. Wide Applications

Galvanized steel coil is highly versatile and can be easily processed for various purposes. It finds extensive use in construction, home appliances, automobile containers, transportation, and more. Additionally, it boasts good coating adhesion and weldability, making it an ideal base metal for PPGI products.


3. Easy to Transport

In terms of transportation, coils are more convenient to handle than GI steel sheets, leading to reduced shipping costs and logistical efficiencies.

Galvanized Steel Coils

Contact Us
  • QQ: 2228721936
  • Skype: lingmai-2005
  • Tel.: +86 757 8383 6678
  • Fax: +86 757 8383 8678
  • E-mail: carson@klsfh.com
  • Mob.: +86 158 1691 5404
  • WhatsApp: +86 158 1691 5404
  • Add.: No.30-33, 2/F, Block 5, Lanshi (International) Matel Trade Center, Chancheng District, Foshan City, Guangdong Province, China.
follow us

Cladding Armor Plate Stainless Steel Sheathing Sheet Metal Cladding Armor Metal Jacketing Sheet Stainless Steel Cladding Facade Steel Panel Overlay