Official Answer
Answer
During the spiral coiling process, significant residual stresses are induced in the material as it is bent into its circular shape. Stress relieving involves heating the rings to a temperature below the critical range (e.g., $750^{\circ}F$ for carbon steel) for a specific duration. This stabilizes the ring's dimensions, prevents 'spring-back' or 'out-of-roundness', and improves the fatigue life by reducing the peak internal stress. For high-precision spiral rings, this process is essential to ensure that the ring stays flat and maintains its specified diameter over its shelf life and operational life.
