Any thin tube of uniform thickness

Values for calculation

$T$ $\mathrm{Nm}$
$A$ $\mathrm{mm^2}$
$U$ $\mathrm{mm}$
$t$ $\mathrm{mm}$
$L$ $\mathrm{mm}$
$G$ $\mathrm{MPa}$

Calculation

Polar moment of inertia

$$K=\cfrac{4\cdot A^2\cdot t}{U}$$

Angle of twist

$$θ=\cfrac{T\cdot 10^3\cdot L}{K\cdot G}$$

Torsion stress (average)

$$τ_{average}=\cfrac{10^3\cdot T}{2\cdot t\cdot A}$$