Hi there,(adsbygoogle = window.adsbygoogle || []).push({});

I'm trying to find a solution to a problem that I thought was straight forward, but am now struggling with.

I've got a shaft with a fixed end set up, where there is a small diameter fixed and then it steps up to a larger diameter which is having a torque applied to it.

I'm trying to find out the maximum torque that can be applied to the larger side before the material starts to shear.

The only things that i know about the shaft are the diameters and material type.

So far I've been using:

T=(τ*J)/r

and

τ=0.557*σ

Where:

T = maximum torque

τ = allowable shear stress

J = polar moment of inertia

r = radius

σ = ultimate tensile strength.

Can anybody help me out? I'm not sure if I've got the equations right or whether I'm going down the correct route.

Cheers

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# Torsional stress on a shaft

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