How do we account for the radial expansion of a wave spring during compression within a bore?

As a wave spring is compressed, the waves flatten, causing the mean diameter $D_m$ to expand. This expansion is defined by $\Delta D = α · f$, where $α$ is the expansion coefficient and $f$ is the deflection. For a spring operating in a bore, the initial clearance must be sufficient to prevent the spring from binding. If binding occurs, the spring rate $k$ increases exponentially, leading to unpredictable load behavior and potential fatigue failure at the wave crests. The calculation for the minimum bore diameter $D_b$ should be $D_b > D_{outer} + \frac{0.02 · (H_f - H_o) · n^2}{D_m}$, where $H_f$ is the free height and $H_o$ is the operating height. This ensures the spring remains 'free-floating' throughout its entire stroke.