What is S280GD galvanized steel?
S280GD is the structural galvanized grade that the purlin industry standardised on: 280 MPa minimum yield gives a C or Z section in 1.5–2.5 mm the capacity for 5–7 m bays under normal roof loads, while the strip is still soft enough (18 % elongation, bend radius 1 × t) to roll-form lips, stiffeners and swages on ordinary tooling. It comes from a low-carbon, manganese-strengthened heat (C ≤ 0.20 %, Mn ≤ 1.70 %), hot-rolled pickled or cold-rolled substrate, hot-dip galvanized with Z275 as the industry coating — the old EN 10147 name Fe E 280 G still appears on drawings, as does the DIN StE 280 Z. Beyond purlins it is the strip for side rails, eave beams, sigma and omega framing sections, heavier cable ladders and solar mounting rails, and for any roll-formed part that carries a design load and lives outdoors. We keep the purlin gauges in stock and slit to the developed width of the section.
Chemical composition
| Element | C | Si | Mn | P | S |
|---|---|---|---|---|---|
| max. % (ladle) | 0.20 | 0.60 | 1.70 | 0.10 | 0.045 |
Typical heat: C 0.07–0.10, Mn 0.50–0.80.
Mechanical properties
| Property | Requirement | Typical value | Note |
|---|---|---|---|
| Yield strength ReH / Rp0.2 | ≥ 280 MPa | 310–360 MPa | fyb = 280 |
| Tensile strength Rm | ≥ 360 MPa | 390–450 MPa | |
| Elongation A80 | ≥ 18 % | 22–28 % | |
| Bend radius (180°) | 1 × t | passes |
Equivalent grades
| System | Grade | Note |
|---|---|---|
| EN 10147 (old) | Fe E 280 G / S280GD+Z | withdrawn |
| DIN 17162 | StE 280 Z | historic |
| ASTM A653 | SS Grade 40 (275 MPa) | Structural Steel |
| JIS G3302 | SGC440 | |
| GB/T 2518 | S280GD+Z |
Zinc coating classes (Z100–Z600)
| Class | Zinc mass (g/m², both sides) | Thickness per side (µm) | Typical life C3 | Where used |
|---|---|---|---|---|
| Z100 | 100 | ≈ 7 | 4–6 years | indoor, painted parts, ducting |
| Z140 | 140 | ≈ 10 | 6–9 years | the Turkish stock standard |
| Z200 | 200 | ≈ 14 | 9–13 years | roofing, outdoor cladding |
| Z275 | 275 | ≈ 20 | 12–18 years | export standard, purlins, structural |
| Z350 | 350 | ≈ 25 | 15–22 years | agriculture, coastal |
| Z450 / Z600 | 450 / 600 | ≈ 32 / 42 | 20–35 years | highway, marine, ground contact |
Life = time to 5 % red rust per ISO 9223 C3 (0.7–2.1 µm zinc loss per year); halve it for C4 industrial-coastal, double it for C2 rural. Spangle: normal (N) or minimised (M); surface quality A (normal) or B (improved, for painting); surface treatment C (chemical passivation), O (oiled), CO (both).
Thickness range and stock sizes
| Thickness | Widths × lengths | Availability |
|---|---|---|
| 1.5 / 2.0 / 2.5 / 3.0 mm | coil 1 250 / 1 500 mm; slit to purlin widths | stock Z275 |
| 1.0 / 1.2 mm | coil 1 250 mm | to order 2–3 weeks |
| 0.50–0.80 mm | coil 1 000 / 1 250 mm | to order 2–3 weeks |
| finished purlins | C / Z 100–350 mm from our line | see C & Z purlins |
Weight per m² and per sheet
| Thickness | kg/m² | 1 000 × 2 000 (kg) | 1 250 × 2 500 (kg) | 1 500 × 3 000 (kg) |
|---|---|---|---|---|
| 0.5 mm | 4.20 | 8.4 | 13.1 | 18.9 |
| 0.7 mm | 5.77 | 11.5 | 18.0 | 26.0 |
| 1 mm | 8.13 | 16.3 | 25.4 | 36.6 |
| 1.2 mm | 9.70 | 19.4 | 30.3 | 43.6 |
| 1.5 mm | 12.05 | 24.1 | 37.7 | 54.2 |
| 2 mm | 15.98 | 32.0 | 49.9 | 71.9 |
| 2.5 mm | 19.90 | 39.8 | 62.2 | 89.6 |
| 3 mm | 23.83 | 47.7 | 74.5 | 107.2 |
Includes Z275 coating; subtract 0.135 kg/m² for Z140.
Forming, welding and design
Roll-forms C, Z, sigma and omega sections with lips and stiffeners at 1 × t inside radius; punching of bolt holes and cleats in-line is routine (clearance 10 %). MAG welding with fume extraction where sections are welded to cleats; bolted connections (M12/M16) are standard. Design to EN 1993-1-3 with fyb = 280 MPa, fu = 360 MPa, core thickness = nominal − 0.04 mm for Z275. For long spans and heavy snow, step up to S350GD rather than to thicker S280GD — the weight saving is usually larger.
Where it is used
- C and Z purlins and side rails, 100–350 mm
- Sigma, omega and heavy light-gauge framing sections
- Eave beams, bracing and sag-rod systems
- Solar mounting rails and posts
- Heavy cable ladders and support systems
- Trailer floor and body cross-members
S280GD vs S350GD for purlins
For bays up to about 6 m under moderate loads S280GD in 1.5–2.0 mm is the economical purlin; beyond that, or under heavy snow and wind, S350GD lets the same section carry 25 % more or the bay grow by a metre for a price difference of about 20 USD/t. Below S280GD, S250GD serves roofing sheet and light profiles. Our finished C & Z purlins are rolled from S280GD by default and S350GD on request.
Price
S280GD is priced about 20 USD/t over DX51D of the same thickness; the bands below are indicative FOB Istanbul for the stocked purlin gauges and for thin coil to order. Slitting to purlin width is priced per ton.
Bands from our weekly export list (September 2026), FOB Istanbul, full-container quantities, excluding freight and certificates. Firm price per project on RFQ within one working day.
Export and packing
We load S280GD galvanized steel as slit or master coils on cradles (VCI paper, strapped, 5–25 t) or as cut-to-length sheet on skids (≤ 3 t, interleaved, edge boards); a 20' container carries one coil to 20 t, a 40' HC two coils or 24 t of sheet. HS 7210 / 7209 / 7208.
| Term | Detail |
|---|---|
| MOQ | One coil (10–20 t) or 5 t of slit strip |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | Stock 1.5–3.0 mm Z275: 3–5 working days; 0.50–1.2 mm to order 2–3 weeks |
| Packing | Coil eye-to-sky, VCI wrap; slit coils on pallets |
| Container / truck | 20' one coil ≤ 20 t; 40' HC two coils |
| Documents | Invoice, packing list, EN 10204 3.1 (3.2 on request), certificate of origin; SASO / SONCAP / PVoC on request |
| Payment | 30% advance, balance against B/L copy; L/C at sight for orders above 100 t |
Certificates and testing
S280GD galvanized steel ships with EN 10204 3.1 certificates cross-referenced to the stencilled heat numbers. Where the project requires it we arrange 3.2 certification with Lloyd's, BV, TÜV or SGS, ultrasonic examination to EN 10160 and Charpy testing at the temperature you specify.
How to order
Specify thickness, coil width or slit widths (developed width of the section), coating Z275 / Z140, tonnage, and whether you want us to roll the purlins — send the schedule and we quote finished sections.
Standards
- EN 10346:2015 — S280GD+Z, 1.0244
- EN 10143 — tolerances
- EN 1993-1-3 — cold-formed design (fyb = 280 MPa)
- EN 10204 3.1
- Former EN 10147 Fe E 280 G
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: S280GD · S250GD · S350GD
Frequently asked questions
What is S280GD?
A structural hot-dip galvanized strip to EN 10346 (1.0244) with guaranteed yield ≥ 280 MPa and tensile ≥ 360 MPa — the standard grade for C and Z purlins and heavier roll-formed profiles; old name Fe E 280 G.
Which grade of steel is used for purlins?
S280GD+Z275 is the industry standard for cold-formed C/Z purlins in Europe and the Middle East; S350GD for long spans and heavy loads; S250GD for light profiles.
What is the difference between S280GD and S350GD?
Guaranteed yield 280 vs 350 MPa: S350GD carries about 25 % more for the same section but bends at 1.5 × t and costs about 20 USD/t more.
What is the ASTM equivalent of S280GD?
ASTM A653 SS Grade 40 (275 MPa yield); JIS G3302 SGC440.
Is S280GD+Z275 in stock?
Yes — 1.5, 2.0, 2.5 and 3.0 mm in 1 250 / 1 500 mm at Dilovası, slit to purlin widths in 3–5 days; thinner gauges in 2–3 weeks.