Shaft Design Calculator (ASME)

Calculate minimum shaft diameter under combined bending and torsional loads using the ASME shaft design code method.

Reference: ASME B106.1M

Inputs

Torque(N·m)

Bending Moment(N·m)

Shaft Material

Factor of Safety

Shaft has a keyway (reduces allowable stress by 25%)

Results

Minimum Calculated Diameter: 36.20mm
Recommended Standard Diameter: 38mm
Allowable Shear Stress: 36.0MPa
Actual Shear Stress (at rec. dia): 31.1MPa

Formula Used

d³ = (16 / π·τ_allow) × √[(K_b·M)² + (K_t·T)²]
τ_allow = min(0.18·S_ut, 0.3·S_y) / FOS

Combined shock & fatigue factors assumed: K_b = 1.5 (minor shocks), K_t = 1.0 (steady torque). Adjust manually for heavy shock loading conditions.

⚠ For preliminary design and educational use only. Verify all results against applicable codes and standards before use in production or safety-critical applications.

About this calculator

Part of our Mechanical Calculators collection. Beams, bolts, springs, gears, bearings, and core ME calculations.

How it works

Calculates minimum shaft diameter under combined bending and torsional loads using the ASME B106.1M shaft design code method, including shock and fatigue factors.

Enter your values in the inputs above and click CALCULATE. Results appear on the right without a page reload. No login and no server upload.

Privacy and accuracy

Every calculation runs locally in your browser. Your design data never leaves your device. Results are intended for preliminary engineering work. Always verify critical designs with qualified review and applicable standards before production use.