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Diameter of Solid Shaft with Torsion Equation and Calculator

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Diameter of Solid Shaft Subjected to Simple Torsion Equation and Calculator

Eq. 1
D = [ 16 Mt / ( π σyd )] (1/3)

where

D = diameter of shaft, m (in)
Mt =
twisting moment, Nm (lbf in)
σy =
stress (tensile or compressive), MPa (psi)

Related:

Source: Shigley, Joseph E., and Charles R. Mischke, Mechanical Engineering Design, 5th ed., New York: McGraw-Hill, 1989.