Explain the importance of 'Pre-setting' in the manufacturing of wave springs for high-cycle fatigue applications.

Pre-setting, or 'removing the set,' involves compressing a wave spring to its solid height or a load beyond its intended operating range. This process induces local plastic deformation at the wave peaks, which creates beneficial residual compressive stresses upon release. According to the Haigh diagram, these residual stresses shift the mean stress $S_m$ downward, significantly increasing the fatigue life $N_f$. For automotive clutch springs made from oil-tempered chrome silicon steel (ASTM A401), pre-setting is a mandatory process step to ensure the component can survive over 10 million cycles without structural failure.