W33×318 vs W36×318
A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.
W33×318 and W36×318 both weigh 318 lb per foot, so the choice comes down to depth and stiffness rather than weight.
W36×318 is the deeper section at a nominal 36 in., versus 33 in.
| Property | W33×318 | W36×318 |
|---|---|---|
| Weight | 318 lb/ft | 318 lb/ft |
| Depth (d) | 35 1/8" | 38 1/4" |
| Flange width (bf) | 16" | 12 3/8" |
| Web thickness (tw) | 1 1/16" | 1 3/16" |
| Flange thickness (tf) | 1 7/8" | 2 1/8" |
| Area (A) | 93.7 in² | 93.4 in² |
| Moment of inertia (Ix) | 19500 in⁴ | 21200 in⁴ |
| Section modulus (Sx) | 1110 in³ | 1110 in³ |
| Plastic modulus (Zx) | 1270 in³ | 1300 in³ |
Open W33×318 in the interactive size chart →
Full detail: W33×318 · W36×318. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.
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