PROGRESUL
A versatile low-carbon structural profile
Q235B flat bar is a hot-rolled low-carbon steel section with a rectangular cross-section, produced to GB/T 700. Its controlled carbon content keeps the grade highly weldable while the manganese content provides dependable yield and tensile strength for everyday structural duty.
Widely used in steel structures, machine frames, brackets, racks, railings and enclosure fabrication, Q235B flat bar offers the best cost-performance balance among ordinary structural steels — easy to cut, drill, bend and weld, available in a wide range of widths and thicknesses, and fully customizable in length.
Why choose Q235B flat bar
Chemical composition (wt%) — GB/T 700 Q235B
| Element | Carbon (C) | Silicon (Si) | Manganese (Mn) | Sulfur (S) | Phosphorus (P) |
|---|---|---|---|---|---|
| Conţinut | ≤ 0.20 | ≤ 0.35 | ≤ 1.40 | ≤ 0.045 | ≤ 0.045 |
Note: single values are maximum limits per GB/T 700. Residual copper ≤ 0.30%. Heat analysis applies to ladle samples.
Mechanical properties (thickness ≤ 16 mm)
| Property | Yield Strength ReH | Tensile Strength Rm | Elongation A | Impact (20°C) | Hardness (approx.) |
|---|---|---|---|---|---|
| Value | ≥ 235 MPa | 370 – 500 MPa | ≥ 26% | ≥ 27 J | ~ 121 HBW |
Physical properties
Common sizes & specifications
| Lăţime (mm) | Grosime (mm) | Lungime | Toleranţă | Margine |
|---|---|---|---|---|
| 20, 25, 30, 40 | 3, 4, 5, 6 | 6 m standard | GB/T 702 | Fully rounded / square |
| 50, 60, 80, 100 | 6, 8, 10, 12 | 6 m / custom | ±0.5 mm (grosime) | Straight, burr-free |
| 120, 150, 200 | 12, 16, 20, 25 | Up to 12 m | GB/T 702 | Straight, deburred |
Sizes beyond this table, customized lengths and non-standard dimensions are available on request.
Where Q235B flat bar is used
- Steel structures, frames and light trusses
- Machine frames, bases and fabricated parts
- Racks, shelves, supports and brackets
- Bridges, railings, guards and handrails
- Electrical cabinets and distribution enclosures
- Agricultural machinery and transport equipment
Processing services & export packaging
Drilling & punching holes
Bending & forming
Shot blasting & derusting
Painting (primer / epoxidic)
Hot-dip galvanizing
Woven fabric or water-proof wrap
Wooden pallet / crate for sea freight
Labels with grade, dimensiune & batch no.
Mill test certificate (MTC) supplied
3rd-party inspection acceptable
Send us your width, thickness and length requirements — we reply within 24 hours with a competitive quote, stock availability and shipping options.
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