Galvanized Structural Steel Grades
S280GD+Z and S350GD+Z Galvanized Steel are engineered to combine structural strength and corrosion resistance, making them ideal for long-term outdoor and industrial environments.
S280GD is a strong, low-alloy structural steel that's widely used in construction and manufacturing. With a minimum yield strength of 280 MPa, it's tough enough for demanding structural tasks. The hot-dip zinc coating provides superior protection against corrosion, guaranteeing extended durability. Thanks to this blend of strength and protection, the S280GD is perfect for structural frames, roofing systems, and other heavy-duty applications.
While both grades share similar zinc coating options, their mechanical performance leads to different design strategies.
Strength-to-Weight Efficiency
Higher strength allows designers to reduce thickness while maintaining safety margins, but this advantage must be balanced against fabrication complexity.
| Design Criterion | S280GD+Z | S350GD+Z |
|---|---|---|
| Strength-to-weight ratio | Balanced | High |
| Thickness reduction potential | Moderate | Significant |
| Structural stiffness | Medium | High |
| Design flexibility | High | Moderate |
S350GD+Z is often chosen when weight reduction is critical, while S280GD+Z is preferred for flexible structural designs.
Zinc Coating and Corrosion Performance
Both grades use the same galvanizing process, meaning corrosion resistance is mainly determined by coating weight.
| Zinc Coating | Typical Service Environment |
|---|---|
| Z100–Z140 | Indoor or dry environments |
| Z180–Z275 | Outdoor and industrial exposure |
From a corrosion protection perspective, S280GD+Z and S350GD+Z perform equally when the same coating specification is applied.
Cost and Project Economics
Material selection should consider total project cost rather than price per ton alone.
| Cost Factor | S280GD+Z | S350GD+Z |
|---|---|---|
| Unit material price | Lower | Higher |
| Fabrication cost | Lower | Higher |
| Steel consumption | Higher | Lower |
| Overall project efficiency | Stable | Optimized for heavy loads |
For many standard construction projects, S280GD+Z delivers excellent cost-performance balance.
Supported Applications
| Industry Sector | Common Choice |
|---|---|
| Light steel buildings | S280GD+Z |
| Industrial plants | S280GD+Z / S350GD+Z |
| Infrastructure projects | S350GD+Z |
| Agricultural structures | S280GD+Z |
S280GD + Z VS S350GD+Z
| Property | S280GD galvanized steel | S350GD galvanized steel |
| Yield Strength | ≥280 MPa | ≥350 MPa |
| Tensile Strength | 380–500 MPa | 350–480 MPa |
| Formability | Excellent | Moderate |
| Weldability | Good | Moderate |
| Cost Efficiency | 15% lower vs. S350GD | Higher material cost |
| Best For | High-strength formable parts | Maximum load-bearing |
Available Steel Grade
| Steel grade | Coating | Yield(MPA) | Tensile(MPA) | Elongation(%) |
| DX51D | Z,ZF | -- | 270-500 | 20 |
| DX52D | Z,ZF | 140-300 | 270-420 | 22 |
| DX53D | Z,ZF | 140-260 | 270-380 | 26 |
| DX54D | Z,ZF | 140-220 | 270-350 | 30 |
| S220GD | Z,ZF | 220 | 300 | 18 |
| S250GD | Z,ZF | 250 | 330 | 17 |
| S280GD | Z,ZF | 280 | 360 | 16 |
| S320GD | Z,ZF | 320 | 390 | 15 |
| S350GD | Z,ZF | 350 | 420 | 14 |
| S400GD | Z,ZF | 400 | 470 | -- |
| S450GD | Z,ZF | 450 | 530 | -- |
| S500GD | Z,ZF | 500 | 560 | -- |
GNEE STEEL offers reliable supply of S280GD+Z and S350GD+Z Galvanized Steel with consistent quality and flexible specifications.
Our product range also includes galvanized steel coils, sheets, strips, and customized profiles, supporting both standard construction and high-performance structural projects.