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### Diameter Combined Torsion and Bending Equation and Calculator

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Diameter of Solid Shaft subjected to Combined Torsion and Bending Equation and Calculator

Preview: Diameter Solid Shaft with Combined Torsion and Bending Calculator

According to maximum normal stress theory

Eq. 1

D = [ 16 / ( π σ_{yd} ) { M_{b} + ( M_{b}^{2}** + **M_{t}^{2} )^{(1/2)} } ] ^{(1/3)}

According to maximum shear stress theory

Eq. 2

D = { 16 / ( π τ_{yd} ) { M_{b}^{2} + M_{t}^{2} )^{(1/2)} } ^{(1/3)}

According to maximum shear energy theory

Eq. 3

D = { 16 / ( π τ_{yd} ) { M_{b}^{2} + 3/4 M_{t}^{2} )^{(1/2)} } ^{(1/3)}

where

*D = *diameter of shaft, m (in)

*M _{b} = *bending moment, Nm (lbf in)

*M*twisting moment, Nm (lbf in)

_{t}=*τ*shear stress, MPa (psi)

_{yd}=*σ*stress (tensile or compressive), MPa (psi)

_{yd}=Related:

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Source:

Machine Design Handbook 2nd Edition, 2001

Prof. Dr. K. Lingaiah

Former Principal, Professor and Head, Department of Mechanical Engineering

University Visvesvaraya College of Engineering, Bangalore University, Bangalore