Galvanized Steel Coil Manufacturer (GI) — Factory Supply | Gengfei
Gengfei supplies hot-dip galvanized (GI) steel coils for roofing, cladding, ductwork, profiles, garage doors, home appliances and general fabrication. As a China-based manufacturer, we control substrate, zinc bath, spangle, and finishing—so you get consistent zinc mass (Z100–Z275), tight tolerances, and on-time delivery. Order full coils, slit coils, or cut-to-length.
24-hour response • Custom widths & coatings • Global sea freight support
Why Buyers Choose Us
Traceability: heat/coil numbers and coating test reports with every shipment
Consistency: stable zinc mass and uniform spangle across the coil
Customization: zero/mini/regular spangle, oiled/chem-treated/AFP, exact coil weight
Cost control: fewer intermediaries, better landed cost
Base Steel & Grades
| Standard | Common Grades | Typical Uses |
|---|---|---|
| EN 10346 | DX51D/DX52D (forming), S250GD–S350GD (structural) | Roofing, profiles, purlins |
| ASTM A653/A653M | CS Type A/B, SS Grade 33–50 | Building & general fabrication |
| JIS G3302 | SGCC/SGCD | HVAC, light gauges |
| GB/T 2518 (GI) | DX51D, S280GD | Domestic spec alignment |
Coating Options (Zinc Mass)
Z100–Z275 (EN) / G30–G90 (ASTM) standard supply; higher/lower on request
Single or double-sided symmetrical/asymmetrical coating per application
Dimensions & Tolerances
| Item | Range |
|---|---|
| Thickness | 0.20–2.50 mm (typical) |
| Width | 600–1,250 mm (custom slit widths available) |
| Coil ID | 508 mm / 610 mm |
| Coil Weight | 3–15 t (or per request) |
| Flatness/Thickness Tol. | per EN/ASTM class or buyer spec |
Applications
Construction: roofing/walls, studs, purlins, gutters, fencing
HVAC: duct and accessories, cable trays
Automotive & Transport: body parts, trailer panels (non-exposed)
Appliance & Furniture: back panels, inner cabinets, shelving
Fabrication: roll-forming, stamping, profiling, punching
How to Specify Your Order
Standard & Grade: e.g., EN 10346 DX51D or S350GD
Coating Mass: e.g., Z275 both sides
Thickness × Width: e.g., 0.50 mm × 1,250 mm
Spangle: zero / mini / regular
Surface Treatment: oiled, chem-treated (Cr-free available), AFP
Form: full coil, slit widths, or cut-to-length; coil ID 508/610 mm, target coil weight
Standards & Tests: coating mass (triple-spot), bend/adhesion, salt spray if needed
Packaging & Incoterms: seaworthy export packing, FOB/CIF destination port
Quality & Standards
Production aligned to EN 10346 / ASTM A653 / JIS G3302 / GB/T 2518
Coating mass verification (single/triple spot), thickness, flatness, surface inspection
RoHS/REACH compliant options; chromate-free treatments available
Full traceability from substrate to coil
FAQs
Q1: GI vs GL (Galvalume)?
GI = zinc-coated; GL = 55% Al-Zn coating. GL offers longer corrosion life in many atmospheres; GI is widely used and easier to weld/paint in general applications.
Q2: What Z value should I choose?
Z275 is common for exterior building use; Z100–Z200 for interior/HVAC. Your environment and paint system decide the optimum.
Q3: Can you supply zero spangle?
Yes. We control bath chemistry and cooling to achieve zero or mini spangle for a smooth, paint-ready surface.
Q4: What are typical lead times and MOQs?
Stock specs ship faster; custom grade/width/coating may require an MOQ. Share your spec—we’ll confirm schedule the same day.
Q5: Do you offer slit coil and cut sheets?
Yes—precision slitting and CTL with burr control and protective wrapping.
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