IACS UR M71 - Crankshaft Scantling Check
Crankshaft pin and journal diameter screening per IACS UR M71 - simplified minimum shaft formula used for scantling approval.
Shaft torque
104,182N·m
Minimum pin diameter
171.6mm
Formula, assumptions, and limits
$$d_{min} = \left(\frac{16 T}{\pi \sigma}\right)^{1/3}$$
Simplified torsional-only approximation. Full UR M71 considers bending, fatigue, and stress concentration factors at the fillet. Apply fatigue factor S ≥ 1.15 for pin fillet.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $T$ | Shaft torque | N·m | power / speed |
| $\sigma$ | Allowable shear stress | N/mm² | material + fatigue factor |
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