Pinned shaft with two grooves
<img src="https://eng-calculations.com/SVG/Roark(and39)s_formulas_for_Stress_and_Strain/Formulas_for_torsional_deformation_and_stress_(TABLE_10(and46)1)/Pinned shaft with two grooves.svg" alt="Pinned_shaft_with_two_grooves" title="Pinned_shaft_with_two_grooves">
https://eng-calculations.com/SVG/Roark(and39)s_formulas_for_Stress_and_Strain/Formulas_for_torsional_deformation_and_stress_(TABLE_10(and46)1)/Pinned shaft with two grooves.svg