Official Answer
Answer
Stacking wave springs 'in series' (end-to-end) increases the total deflection while keeping the load $P$ the same as a single spring. The total rate $K_{total} = k / n_{springs}$. This is effectively what a multi-turn Crest-to-Crest spring is. Stacking 'in parallel' (nesting one inside another) increases the load capacity for a given deflection, with $K_{total} = k \cdot n_{springs}$, but it increases the risk of inter-turn friction. In series stacking, it is vital to use a 'shim' or a 'washer' between springs if they are not designed with flat ends to prevent the wave peaks from nesting into each other, which would cause the assembly to behave like a single, much stiffer spring.
