Hot-Dip Galvanized Steel Coils (GI)

-- Steady & Reliable Manufacturer --

Introduction

Hot-Dip Galvanized (GI) Steel Coils are the fundamental product for many corrosion-resistant applications. Produced by continuously passing cold-rolled steel through a molten zinc bath, the resulting zinc coating metallurgically bonds to the steel. This provides sacrificial protection against rust and environmental damage, making it the essential substrate for all subsequent pre-painted (PPGI) products. It offers excellent workability and cost-effective corrosion resistance for applications requiring unpainted, yet protected, steel.

We offer GI coils in a range of zinc coating masses (Z), surface finishes (spangle), and steel grades to meet varied structural and manufacturing requirements.

Specifications

Parameter	Value/Range
Coating Mass (Z)	Z60 to Z275 g/m簡 (Total both sides)
Base Material	Cold Rolled Steel (CR)
Surface Finish	Regular Spangle (RS), Minimum Spangle (MS), Zero Spangle (ZS)
Treatment	Chromated, Oiled, Chromated & Oiled, Anti-fingerprint
Grades	Commercial (CQ), Drawing (DQ), Structural (HSS)
Thickness Range	0.14mm to 3.0mm
Width Range	600mm to 1500mm

Protection Mechanism: The zinc sacrifices itself to protect the underlying steel, meaning even if the surface is scratched, the steel won't rust until the surrounding zinc is depleted.

Application

Light Steel Framing: Studs, tracks, and purlins for construction.
HVAC Systems: Ductwork, air conditioners, and ventilation equipment casings.
Automotive Parts: Muffler components and non-exposed structural parts.
Water & Storage Tanks: Industrial and agricultural fluid storage containers.

Advantages

Exceptional Cost-Effectiveness: The most economical way to achieve robust corrosion protection.
Sacrificial Protection: Offers protection even at cut edges and scratches.
Excellent Formability: Highly suited for complex forming operations without damaging the coating (especially zero-spangle finishes).
Widespread Acceptance: A globally recognized and universally specified material for basic steel protection.

Payment & Shipping

Custom Slitting: We offer custom coil slitting down to narrow widths to meet specific manufacturing line requirements.
Incoterms: We handle bulk orders under various terms (FOB, CIF, CFR) with reliable international logistics partners.
Lead Time: Standard thickness and Z-mass coils are frequently stocked or quickly produced (15-20 days).

Frequently Asked Questions

Q: What is the difference between Regular Spangle and Zero Spangle?
A: Regular Spangle has visible zinc crystals, suitable for general use. Zero Spangle has been processed to have an invisible, smoother finish, which is ideal for subsequent painting or complex forming.

Q: Can GI coils be painted directly?
A: GI requires proper surface preparation, including cleaning and using an etch or zinc-compatible primer (like chromate treatment), before applying a topcoat. Pre-painted steel (PPGI) eliminates this step.

CONTACT WITH US

Zhejiang Tiannv Color Steel Co., Ltd.

Enjoying good reputation from all the customers worldwide, we are the reliable partner you can trust in China.

Zhejiang Tiannv Color Steel Co., Ltd was established in January 2003, located in Zhejiang Province, which is a Sino-Hong Kong joint venture with a registered capital of 50 million RMB. As China Hot-Dip Galvanized Steel Coils (GI) Manufacturers and Hot-Dip Galvanized Steel Coils (GI) Factory, the company covers an area of 50000㎡, and a workshop area of 12000㎡. Company’s main products are hot galvanized steel coil, aluzinc coil, prepainted steel coils (PPGI / PPGL), prepainted aluminum coil, printed PPGI for household appliance, roofing/corrugated PPGI sheet, and PPGI paint. Currently, we have 85 skilled employees, 5 professional engineers and 15 experienced office personnel. The manufacture capability of our production line is nearly 100,000 metric tons per year.

Our company produces high quality color coated steel, and imposes strict quality control over the prepainted steel coils. We use good quality hot-dip galvanized steel coils or Alu-Zinc coated steel coils as base sheet and strictly select coated paints, which gives quality promise to customers and competitive advantage for our company.

Recommended LINS: Prepainted Galvanized Steel Coils (PPGI) 0.5mm Thickness Steel Coils 1000mm Width Steel Coils