How should wave springs be oriented in a 'series' stack to ensure uniform load distribution?

When stacking single-turn wave springs in series to increase deflection, they must be oriented such that the waves are 'in-phase' (peak-to-peak) or using a Crest-to-Crest multi-turn design. If single-turn springs are randomly oriented, the wave peaks may slide into the valleys of the adjacent spring (nesting), which would dramatically increase the spring rate and reduce the total deflection. For high-vibration environments, using a multi-turn Crest-to-Crest spring is preferred over a stack of single-turn springs because the integral construction eliminates the risk of component misalignment and frictional wear between the individual spring interfaces.