Analyze Effect of Fillet on Polygonal Shaft and Disc Assembly
The polygonal shaft and disc has its own advantage of assembly with little or no interference to be used for the
assembled components, in addition to very less stress concentration. This method can be very beneficial to heavy duty
applications such as turbo machinery. It is possible to transfer higher torque smoothly with polygonal shaft. Usually loboid
shaft cross section and identical shaped bore is used, however keeping the sides flat with fillet at the corners will give
reasonable results. The advantage of fillet over lobed profile is that the former profile takes less effort to manufacture. This
paper gives an idea about the effect of fillet radius in polygonal shaft-disc assembly. An attempt is made to test the triangular
profile shaft cross section with different fillet radius at the corners. The analysis reveals that as the fillet radius increases, the
stress decreases drastically in addition to healthy contact pressure and increased stickiness for tighter connection between the
shaft and disc assembly.
Keywords - Polygonal Shaft, Polygonal Disc, Fillet Radius, Turbo Machine.