Official Answer
Answer
For high-volume production, manual winding is inefficient. Instead, a tapered sleeve (for bores) or a tapered mandrel (for shafts) is used. The ring is pushed over the taper, which gradually expands or contracts it to the required assembly diameter. A plunger then pushes the ring into the final position where it snaps into the groove. The taper angle should be shallow (typically $5^{\circ}$ to $10^{\circ}$) to minimize the force required and prevent over-stressing the material. The surface of the mandrel must be hardened and polished to prevent 'galling' or scratching the ring's finish, which could lead to future fatigue crack initiation.
