Steel Beam Sizes / AISC / W-Shapes / W18 / W18x55
W18x55 Dimensions, Weight and Section Properties
AISC Wide flange · v16.0
W18x55: 18.1 in depth, 7.53 in flange width, 55 lb/ft weight. View the full dimensions and properties in imperial and metric units below.
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Section diagram
W18x55 dimensions
Not to scale. Dimensions shown for reference.
Section properties
Symbols match the steel section finder. Imperial and metric values are shown side by side.
| Property | Imperial | Metric |
|---|---|---|
| Weight | 55.00 lb/ft | 82.00 kg/m |
| Depth, d | 18.10 in | 460.00 mm |
| Flange width, bf | 7.53 in | 191.00 mm |
| tw | 0.390 in | 9.910 mm |
| tf | 0.630 in | 16.000 mm |
| Area | 16.20 in² | 10,500.00 mm² |
| Ix | 890.00 in⁴ | 370,000,000 mm⁴ |
| Iy | 44.90 in⁴ | 18,700,000 mm⁴ |
| Sx | 98.30 in³ | 1,610,000 mm³ |
| Sy | 11.90 in³ | 195,000.00 mm³ |
| Zx | 112.00 in³ | 1,840,000 mm³ |
| Zy | 18.50 in³ | 303,000.00 mm³ |
| rx | 7.41 in | 188.00 mm |
| ry | 1.67 in | 42.40 mm |
| J | 1.66 in⁴ | 691,000.00 mm⁴ |
| Cw | 3,430.00 in⁶ | 921,000,000,000 mm⁶ |
Alternatives
Useful nearby sections
Compare weight neighbors, another Ix option, and a nearby depth series when available, with percent change versus W18x55.
Lighter in W18
W18x50
- Weight
- 50.0 lb/ft (-9.1%)
- Depth
- 18.00 in (-0.6%)
- Ix
- 800.0 in⁴ (-10%)
Heavier in W18
W18x60
- Weight
- 60.0 lb/ft (+9.1%)
- Depth
- 18.20 in (+0.6%)
- Ix
- 984.0 in⁴ (+11%)
Another Iₓ option in W18
W18x46
- Weight
- 46.0 lb/ft (-16%)
- Depth
- 18.10 in (0.0%)
- Ix
- 712.0 in⁴ (-20%)
Similar weight in W21
W21x55
- Weight
- 55.0 lb/ft (0.0%)
- Depth
- 20.80 in (+15%)
- Ix
- 1,140.0 in⁴ (+28%)
Source: AISC Shapes Database v16.0 · Methodology