Shaft design

Gives the diameter a shaft in pure torsion needs — a transmission shaft, say — from the shock factor and the allowable torsional shear stress.

Gives the diameter a shaft in pure bending needs, from the shock factor and the allowable bending stress.

For a shaft under torsion and bending together. It finds the equivalent torque and equivalent bending moment, then takes the larger of the two diameters they call for.

Gives the strength and twist ratios for a keyway, and the allowable torsional stress that follows from them.

Finds the speed at which a rotating shaft resonates, for the support condition and mass treatment you choose.