
300×300×6 mm S420MC–S700MC High-Strength Square Hollow Section
300x300x6mm Steel high-strength square tube in S420MC, S500MC, S600MC, S700MC to EN 10219 / EN 10149-2, with an uncoated steel surface suitable for further processing or painting. Nominal weight 54.662 kg/m.
Minimum order
Minimum 10 t per size. If the size is already in the current production cycle, we can accept orders from 5 t. Standard length 6 m; 4–12 m on request. We confirm the minimum, lead time and grade in your quote.
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Minimum order: 10 t per size (from 5 t if the size is in production)
Applications & Usage
This heavy-duty structural Steel high-strength square tube is commonly specified for framework, support structures, machinery bases, and industrial equipment. The 6mm wall thickness provides superior load-bearing capacity while maintaining workability. The natural mill finish provides a cost-effective solution for applications where aesthetics are secondary. Available in standard lengths of 6m, this profile can be easily cut, drilled, and welded to suit your specific requirements.
Technical Specifications
| Specification | Value |
|---|---|
| Dimensions | 300mm × 300mm × 6mm |
| Weight per Meter | 54.662 kg/m |
| Material | Steel |
| Alloy/Grade | S420MC, S500MC, S600MC, S700MC |
| Standard | EN 10219 / EN 10149-2 |
| Standard Length | 6m |
| Minimum Order per Size | 10 t |
| Cut-to-Length Range | 4000 – 12000 mm |
Section Properties
Nominal values calculated from nominal dimensions to EN 10219-2.
| Property | Value |
|---|---|
| Cross-sectional area(A) | 69.6 cm² |
| Second moment of area(I) | 9964 cm⁴ |
| Radius of gyration(i) | 12.0 cm |
| Elastic section modulus(Wel) | 664 cm³ |
| Plastic section modulus(Wpl) | 764 cm³ |
| Torsional inertia constant(It) | 15434 cm⁴ |
| Torsional modulus constant(Ct) | 997 cm³ |
| Surface area per metre(As) | 1.18 m²/m |
| Length per tonne | 18.3 m |
High-strength grades for this size
Strength and indicative capacity for each grade this size is rolled in, compared with the S355J2H wall that carries the same bending load in the same outer size.
| Grade | Min. yield ReH | Tensile Rm | Bending Wel·ReH | Axial A·ReH | S355J2H equivalent |
|---|---|---|---|---|---|
| S420MC | 420 MPa | 480–620 MPa | 279 kNm | 2925 kN | 8 mm · 71.6 kg/m (+31%) |
| S500MC | 500 MPa | 550–700 MPa | 332 kNm | 3482 kN | 10 mm · 88.4 kg/m (+62%) |
| S600MC | 600 MPa | 650–820 MPa | 399 kNm | 4178 kN | 12 mm · 104 kg/m (+90%) |
| S700MC | 700 MPa | 750–950 MPa | 465 kNm | 4874 kN | 14 mm · 119 kg/m (+118%) |
In S700MC, this section (54.7 kg/m) carries the elastic bending load of a 14 mm S355J2H wall in the same outer size (119 kg/m), which is 118% heavier per metre.
Indicative values from nominal dimensions: Wel × ReH and A × ReH, without buckling, cross-section class or partial safety factors. Not a design check.
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