W40×392 vs W40×397

A side-by-side comparison of two AISC wide-flange beams, 16th Edition. Detailing dimensions to the nearest 1/16 in.

W40×397 is the heavier section at 397 lb per foot, versus 392 for W40×392 (5 lb/ft more).

Both are nominally 40 in. deep.

W40×397 has the greater bending strength: section modulus Sx of 1560 in³ versus 1440, about 8% more.

PropertyW40×392W40×397
Weight392 lb/ft397 lb/ft
Depth (d)41 5/8"41"
Flange width (bf)12 3/8"16 1/8"
Web thickness (tw)1 7/16"1 1/4"
Flange thickness (tf)2 1/2"2 3/16"
Area (A)116 in²117 in²
Moment of inertia (Ix)29900 in⁴32000 in⁴
Section modulus (Sx)1440 in³1560 in³
Plastic modulus (Zx)1710 in³1800 in³

Open W40×392 in the interactive size chart →

Full detail: W40×392 · W40×397. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.

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