W 40X278 vs HE 1000 x 415
W 40X278 is an W section from the American AISC Shapes Database; HE 1000 x 415 is the closest equivalent in the European (Continental) range. They are close to interchangeable in bending: 19500.6 cm³ against 19600 cm³ of plastic modulus, a difference of 0.5%. They weigh essentially the same, 413.7 kg/m and 415 kg/m. Both are about 1021 mm deep, so either fits the same construction zone.
| Property | W 40X278 W | HE 1000 x 415 HE | Difference |
|---|---|---|---|
| Mass | 413.7 kg/m | 415 kg/m | -0.3% |
| Depth | 1021.1 mm | 1020 mm | +0.1% |
| Width | 304.8 mm | 304 mm | +0.3% |
| Web thickness | 26.2 mm | 26 mm | +0.8% |
| Flange thickness | 46 mm | 46 mm | same |
| Area | 531 cm² | 529 cm² | +0.4% |
| Second moment, major (Iy) | 853,274 cm⁴ | 853,000 cm⁴ | same |
| Plastic modulus, major (Wpl,y) | 19,500.6 cm³ | 19,600 cm³ | -0.5% |
| Elastic modulus, major (Wel,y) | 16,714.8 cm³ | 16,700 cm³ | +0.1% |
| Second moment, minor (Iz) | 21,686 cm⁴ | 21,700 cm⁴ | -0.1% |
| Plastic modulus, minor (Wpl,z) | 2,294.2 cm³ | 2,300 cm³ | -0.3% |
| Radius of gyration, minor (iz) | 6.4 cm | 6.41 cm | -0.2% |
| Torsion constant (It) | 2,706 cm⁴ | 2,700 cm⁴ | +0.2% |
W 40X278 to AISC Shapes Database v16.0; HE 1000 x 415 to EN 10365 · Continental Steel. Difference is expressed relative to HE 1000 x 415.
How to choose between them
On stiffness, W 40X278 has the larger second moment of area: 853,274 cm⁴ against 853,000 cm⁴, a difference of 0.0%. 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 (47.1 against 47.2 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.
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 HE to EN 10365 · 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, these two are genuine equivalents. Pick whichever your supplier stocks and the rest of the frame already uses.