Mild Steel Sections
Steel Source Australia stocks the complete range of Australian standard mild steel structural sections — Universal Beams, Universal Columns, Parallel Flange Channels, Equal & Unequal Angles, Flat Bar, Round Bar, Square Bar, RHS, SHS, CHS, Plate and Chequer Floor Plate. All sections supplied to the relevant AS/NZS standard. Custom cut-to-length available. Australia-wide delivery.
260+ SKUs — kg/m mass · dimensions · standard lengths
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Universal Beams (UB) are the primary structural section for floor beams, rafters, portal frames and general structural applications across residential, commercial and industrial construction. The "I" profile concentrates material in the flanges where bending stress is highest, delivering excellent strength-to-weight efficiency. Supplied to AS/NZS 3679.1:2010 Grade 300 (minimum yield strength 300 MPa for sections ≤17mm flange thickness; 280 MPa for heavier sections). Standard mill lengths 9m and 12m; custom cut-to-length available.
| Code | Description | |
|---|---|---|
| 100UB8-9M | 100 UB 8.0 | |
| 100UB8-12M | 100 UB 8.0 | |
| 150UB14-9M | 150 UB 14.0 | |
| 150UB14-12M | 150 UB 14.0 | |
| 150UB18-9M | 150 UB 18.0 | |
| 150UB18-12M | 150 UB 18.0 | |
| 180UB16-9M | 180 UB 16.1 | |
| 180UB16-12M | 180 UB 16.1 | |
| 180UB18-9M | 180 UB 18.1 | |
| 180UB18-12M | 180 UB 18.1 | |
| 180UB22-9M | 180 UB 22.2 | |
| 180UB22-12M | 180 UB 22.2 | |
| 200UB18-9M | 200 UB 18.2 | |
| 200UB18-12M | 200 UB 18.2 | |
| 200UB22-9M | 200 UB 22.3 | |
| 200UB22-12M | 200 UB 22.3 | |
| 200UB25-9M | 200 UB 25.4 | |
| 200UB25-12M | 200 UB 25.4 | |
| 200UB29-9M | 200 UB 29.8 | |
| 200UB29-12M | 200 UB 29.8 | |
| 250UB25-9M | 250 UB 25.7 | |
| 250UB25-12M | 250 UB 25.7 | |
| 250UB31-9M | 250 UB 31.4 | |
| 250UB31-12M | 250 UB 31.4 | |
| 250UB37-9M | 250 UB 37.3 | |
| 250UB37-12M | 250 UB 37.3 | |
| 310UB32-9M | 310 UB 32.0 | |
| 310UB32-12M | 310 UB 32.0 | |
| 310UB40-9M | 310 UB 40.4 | |
| 310UB40-12M | 310 UB 40.4 | |
| 310UB46-9M | 310 UB 46.2 | |
| 310UB46-12M | 310 UB 46.2 | |
| 360UB45-9M | 360 UB 44.7 | |
| 360UB45-12M | 360 UB 44.7 | |
| 360UB51-9M | 360 UB 50.7 | |
| 360UB51-12M | 360 UB 50.7 | |
| 360UB57-9M | 360 UB 56.7 | |
| 360UB57-12M | 360 UB 56.7 | |
| 410UB54-9M | 410 UB 53.7 | |
| 410UB54-12M | 410 UB 53.7 | |
| 410UB60-9M | 410 UB 59.7 | |
| 410UB60-12M | 410 UB 59.7 | |
| 460UB67-9M | 460 UB 67.1 | |
| 460UB67-12M | 460 UB 67.1 | |
| 460UB74-9M | 460 UB 74.6 | |
| 460UB74-12M | 460 UB 74.6 | |
| 460UB82-9M | 460 UB 82.1 | |
| 460UB82-12M | 460 UB 82.1 | |
| 530UB82-9M | 530 UB 82.0 | |
| 530UB82-12M | 530 UB 82.0 | |
| 530UB92-9M | 530 UB 92.4 | |
| 530UB92-12M | 530 UB 92.4 |
Universal Columns (UC) have a wider flange-to-depth ratio than UBs, making them the preferred section for axially loaded columns, posts and compression members. The near-square profile provides high radius of gyration in both axes, reducing effective slenderness and improving buckling resistance. Supplied to AS/NZS 3679.1:2010 Grade 300. Standard mill lengths 9m and 12m.
| Code | Description | |
|---|---|---|
| 100UC15-9M | 100 UC 14.8 | |
| 100UC15-12M | 100 UC 14.8 | |
| 150UC23-9M | 150 UC 23.4 | |
| 150UC23-12M | 150 UC 23.4 | |
| 150UC30-9M | 150 UC 30.0 | |
| 150UC30-12M | 150 UC 30.0 | |
| 150UC37-9M | 150 UC 37.2 | |
| 150UC37-12M | 150 UC 37.2 | |
| 200UC46-9M | 200 UC 46.2 | |
| 200UC46-12M | 200 UC 46.2 | |
| 200UC52-9M | 200 UC 52.2 | |
| 200UC52-12M | 200 UC 52.2 | |
| 200UC60-9M | 200 UC 59.5 | |
| 200UC60-12M | 200 UC 59.5 | |
| 250UC73-9M | 250 UC 72.9 | |
| 250UC73-12M | 250 UC 72.9 | |
| 250UC89-9M | 250 UC 89.5 | |
| 250UC89-12M | 250 UC 89.5 | |
| 310UC97-9M | 310 UC 96.8 | |
| 310UC97-12M | 310 UC 96.8 | |
| 310UC118-9M | 310 UC 117.9 | |
| 310UC118-12M | 310 UC 117.9 |
Technical Reference
Mild Steel Specifications
Full size ranges, standard lengths, lengths per tonne and bundle sizes for all mild steel sections. Data sourced from AS/NZS 3679.1:2010, AS/NZS 1163:2016 and AS/NZS 3678:2016 published section property tables.
Standard Lengths, Lengths Per Tonne & Bundle Sizes
| Section | Size Range | Standard Lengths | Mass Range (kg/m) | Lengths per Tonne* | Typical Bundle |
|---|---|---|---|---|---|
| Universal Beam (UB) | 100UB8 – 610UB125 | 9m, 12m | 8.0 – 125 | ~9 (12m @ 125kg/m) to ~139 (9m @ 8kg/m) | 1–4 lengths |
| Universal Column (UC) | 100UC15 – 310UC137 | 9m, 12m | 14.8 – 137 | ~6 (12m @ 137kg/m) to ~75 (9m @ 14.8kg/m) | 1–4 lengths |
| Parallel Flange Channel (PFC) | 75PFC – 380PFC | 9m, 10.5m, 12m | 5.92 – 55.2 | ~15 (12m @ 55.2kg/m) to ~188 (9m @ 5.92kg/m) | 4–10 lengths |
| Equal Angle (EA) | 20×20×3 – 200×200×26 | 6m, 7.5m, 9m, 12m | 0.88 – 77.8 | ~1 (12m @ 77.8kg/m) to ~190 (6m @ 0.88kg/m) | 5–20 lengths |
| Unequal Angle (UA) | 65×50×5 – 150×100×12 | 6m, 9m, 12m | 4.35 – 19.0 | ~4 (12m @ 19kg/m) to ~38 (6m @ 4.35kg/m) | 5–15 lengths |
| Flat Bar | 10×3 – 300×25mm | 6m | 0.24 – 58.9 | ~3 (6m @ 58.9kg/m) to ~694 (6m @ 0.24kg/m) | 5–50 lengths |
| Round Bar | 6mm – 39mm dia | 6m | 0.222 – 9.42 | ~18 (6m @ 9.42kg/m) to ~751 (6m @ 0.222kg/m) | 10–50 lengths |
| Square Bar | 10×10 – 65×65mm | 6m | 0.785 – 33.2 | ~5 (6m @ 33.2kg/m) to ~212 (6m @ 0.785kg/m) | 5–30 lengths |
| RHS | 38×25×1.6 – 400×300×16 | 8m, 9m | 1.29 – 142 | ~1 (9m @ 142kg/m) to ~97 (8m @ 1.29kg/m) | 1–10 lengths |
| SHS | 20×20×1.6 – 400×400×16 | 8m, 9m | 0.89 – 185 | ~1 (9m @ 185kg/m) to ~140 (8m @ 0.89kg/m) | 1–10 lengths |
| CHS | 21.3×1.6 – 323.9×12.7 | 6m, 9m | 0.77 – 97.8 | ~1 (9m @ 97.8kg/m) to ~216 (6m @ 0.77kg/m) | 1–10 lengths |
| Steel Plate (Grade 250) | 3mm – 100mm thk | 2400×1200, 3000×1200, custom | 23.6 – 785 kg/sheet | N/A — sold by sheet/tonne | Per sheet or pallet |
* Lengths per tonne are approximate, calculated as 1000 ÷ (mass kg/m × length m). Actual count varies with permissible length tolerances per AS/NZS 3679.1:2010 Clause 10.
Hot-Rolled Structural Sections — AS/NZS 3679.1:2010
Universal Beams (UB), Universal Columns (UC), Parallel Flange Channels (PFC), Equal Angles (EA) and Unequal Angles (UA) are all supplied to AS/NZS 3679.1:2010 Grade 300. Merchant bar (Flat Bar, Round Bar, Square Bar) is also covered under this standard.
Grade 300 specifies a minimum yield strength of 300 MPa for sections with flange thickness ≤17mm, and 280 MPa for heavier sections. Tensile strength range is 440–600 MPa. All sections are hot-rolled from continuously cast steel billets.
Equal Angles range from 20×20mm to 200×200mm in thicknesses from 3mm to 26mm. Standard lengths are 6m, 7.5m, 9m and 12m — not all sizes are available in all lengths. Channels (PFC) range from 75×40mm to 380×100mm; standard lengths 9m, 10.5m and 12m.
Cold-Formed Hollow Sections — AS/NZS 1163:2016
Rectangular Hollow Sections (RHS), Square Hollow Sections (SHS) and Circular Hollow Sections (CHS) are supplied to AS/NZS 1163:2016 Grade C350L0.
Grade C350L0 specifies a minimum yield strength of 350 MPa and minimum tensile strength of 430 MPa. The "L0" suffix denotes Charpy impact testing at 0°C. RHS and SHS are available in standard lengths of 8m and 9m; CHS in 6m and 9m.
RHS sizes range from 38×25mm to 400×300mm; SHS from 20×20mm to 400×400mm; CHS from 21.3mm OD to 323.9mm OD. Wall thicknesses from 1.6mm to 16mm depending on section size.
Structural Steel Plate — AS/NZS 3678:2016
Mild steel plate and chequer floor plate are supplied to AS/NZS 3678:2016 in Grade 250 (min yield 250 MPa) or Grade 350 (min yield 360 MPa for ≤11mm thickness).
Standard sheet sizes are 2400×1200mm and 3000×1200mm. Larger format sheets (2400×6000mm, 3000×6000mm) and custom cut-to-size are available. Plate thicknesses from 3mm to 100mm. Mass of a 2400×1200×6mm Grade 250 plate is approximately 135kg.
Universal Beams — Size Range & Lengths Per Tonne
UB sections range from 100UB8 (8.0 kg/m) to 610UB125 (125 kg/m), supplied in standard lengths of 9m and 12m to AS/NZS 3679.1:2010 Grade 300. The 150UB range (14–18 kg/m) is the most commonly stocked residential and light commercial section.
Lengths per tonne at 12m: 150UB14 = ~6 lengths/t; 200UB25 = ~3 lengths/t; 310UB32 = ~3 lengths/t; 410UB54 = ~2 lengths/t. At 9m: multiply by 12/9 = 1.33×.
Universal Columns range from 100UC15 (14.8 kg/m) to 310UC137 (137 kg/m), also in 9m and 12m standard lengths. UC sections have wider, thicker flanges than UB sections, making them ideal for axially loaded columns.
Merchant Bar — Flat, Round & Square
Flat Bar is available from 10×3mm to 300×25mm in standard 6m lengths. Common sizes include 25×3, 25×6, 32×6, 40×5, 50×5, 50×6, 65×6, 75×6, 100×6, 100×8, 150×10 and 200×12mm. Supplied to AS/NZS 3679.1:2010 Grade 300.
Round Bar ranges from 6mm to 39mm diameter in standard 6m lengths. Common diameters: 6, 8, 10, 12, 16, 20, 25, 32mm. A 12mm round bar weighs 0.888 kg/m — one tonne = ~188 lengths at 6m.
Square Bar ranges from 10×10mm to 65×65mm in standard 6m lengths. Common sizes: 10, 12, 16, 20, 25, 32, 40, 50mm. A 20mm square bar weighs 3.14 kg/m — one tonne = ~53 lengths at 6m.
Cut-to-Length & Permissible Tolerances
Steel Source Australia offers a custom cut-to-length service on all sections. Lengths are subject to permissible deviations in accordance with the relevant Australian Standard. Under AS/NZS 3679.1:2010 Clause 10, the permissible length deviation for hot-rolled sections is +100mm / −0mm for lengths up to 6m, and +150mm / −0mm for lengths over 6m.
For hollow sections under AS/NZS 1163:2016, the permissible length deviation is ±0.5% of the ordered length, with a minimum of ±5mm. Cut-to-length orders are subject to minimum quantity requirements — contact us for details.
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No minimum orders. Custom cut-to-length on all sections. Fast dispatch with Australia-wide delivery. Add items to your enquiry above or contact us directly for a prompt quote.