W40×372 vs W40×392

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

W40×392 is the heavier section at 392 lb per foot, versus 372 for W40×372 (20 lb/ft more).

Both are nominally 40 in. deep.

W40×372 has the greater bending strength: section modulus Sx of 1460 in³ versus 1440, about 1% more.

PropertyW40×372W40×392
Weight372 lb/ft392 lb/ft
Depth (d)40 5/8"41 5/8"
Flange width (bf)16 1/8"12 3/8"
Web thickness (tw)1 3/16"1 7/16"
Flange thickness (tf)2 1/16"2 1/2"
Area (A)110 in²116 in²
Moment of inertia (Ix)29600 in⁴29900 in⁴
Section modulus (Sx)1460 in³1440 in³
Plastic modulus (Zx)1680 in³1710 in³

Open W40×372 in the interactive size chart →

Full detail: W40×372 · W40×392. Verify critical dimensions against the current AISC Steel Construction Manual before fabrication.

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