Official Answer
Answer
End-play is the axial clearance between the retained part and the retaining ring. If excessive end-play exists, the retained part can act like a slide-hammer during machine start/stop cycles, delivering high-energy impacts to the ring. This leads to 'Impact Fatigue'. The ring will show signs of mushrooming or localized deformation on the contact face. To resolve this, designers should use 'Cusp' or 'V-shaped' wave springs behind the spiral ring to take up all axial clearance, ensuring the ring is always under a slight preload and preventing the kinetic energy buildup of moving parts.
