W 24X103 vs H-600x300x12x20-151
W 24X103 is an W section from the American AISC Shapes Database; H-600x300x12x20-151 is the closest equivalent in the European (Continental) range. W 24X103 carries more bending: 4588.4 cm³ of plastic modulus against 4489 cm³, 2.2% more. They weigh essentially the same, 153.3 kg/m and 151 kg/m. W 24X103 is deeper, 622.3 mm against 588 mm, which matters where the floor zone is tight.
| Property | W 24X103 W | H-600x300x12x20-151 MB & MC | Difference |
|---|---|---|---|
| Mass | 153.3 kg/m | 151 kg/m | +1.5% |
| Depth | 622.3 mm | 588 mm | +5.8% |
| Width | 228.6 mm | 300 mm | -23.8% |
| Web thickness | 14 mm | 12 mm | +16.7% |
| Flange thickness | 24.9 mm | 20 mm | +24.5% |
| Area | 195.5 cm² | 192 cm² | +1.8% |
| Second moment, major (Iy) | 124,869 cm⁴ | 118,100 cm⁴ | +5.7% |
| Plastic modulus, major (Wpl,y) | 4,588.4 cm³ | 4,489 cm³ | +2.2% |
| Elastic modulus, major (Wel,y) | 4,014.8 cm³ | 4,018 cm³ | -0.1% |
| Second moment, minor (Iz) | 4,953 cm⁴ | 9,025 cm⁴ | -45.1% |
| Plastic modulus, minor (Wpl,z) | 680.06 cm³ | 928 cm³ | -26.7% |
| Radius of gyration, minor (iz) | 5.05 cm | 6.85 cm | -26.3% |
| Torsion constant (It) | 294.3 cm⁴ | 241 cm⁴ | +22.1% |
W 24X103 to AISC Shapes Database v16.0; H-600x300x12x20-151 to Continental Steel. Difference is expressed relative to H-600x300x12x20-151.
How to choose between them
On stiffness, W 24X103 has the larger second moment of area: 124,869 cm⁴ against 118,100 cm⁴, a difference of 5.7%. This matters more often than the strength comparison, because on normal floor spans deflection rather than bending capacity sets the beam size - so if the two are close on modulus but apart on inertia, the stiffer one is usually the better answer even when it is not the stronger one.
Measured as bending capacity per kilogram, the two are equally efficient (29.9 against 29.7 cm³ per kg/m), so on a pure steel-tonnage basis there is nothing to choose between them. The decision comes down to availability, connection detailing and what the rest of the frame uses.
The two diverge much more about the minor axis: H-600x300x12x20-151 has 928 cm³ of minor-axis plastic modulus against 680.06 cm³, 26.7% more. If the member sees any minor-axis bending, or if it is unrestrained over a long length and lateral-torsional buckling governs, that gap decides the comparison even though the major-axis numbers looked equivalent.
These come from different catalogues, so treat the swap as a design change rather than a like-for-like substitution. W sections are specified to AISC Shapes Database v16.0 and MB & MC to Continental Steel; the steel grades, tolerances and available lengths differ, connection details and bolt gauges are set out differently, and the two are rarely both stocked in the same market. Check availability before changing a section on a drawing to save a marginal amount of weight.
In short, W 24X103 is the stronger section and H-600x300x12x20-151 is the lighter one; where those are the same section, it is the clear choice, and where they are not, decide on whether your design is governed by capacity or by tonnage.