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Shaft Design
Size a rotating shaft for combined bending and torsion: the fatigue safety factor by the distortion-energy Goodman criterion, first-cycle yield, and the smallest diameter that meets your target. Updates as you type.
Why shafts fail by fatigue, and what the Goodman line means: shaft design, explained.
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Material
Section
Feature factors are Shigley's first-iteration estimates; they are the theoretical K_t, which is conservative as K_f.
Loads at the section
A shaft turning under a steady side load sees its bending moment as fully alternating, M_a, and a steady torque as mean, T_m.