What are the consequences of 'Over-Spreading' a spiral retaining ring during installation?

Over-spreading occurs when a ring is expanded (external) or contracted (internal) beyond its elastic limit during installation. This results in permanent plastic deformation, meaning the ring will not return to its original 'cling' diameter. In an external ring, this leaves a gap between the ring ID and the groove bottom, drastically reducing the clinging speed and making the ring susceptible to falling off under vibration. In an internal ring, over-contraction makes the ring 'loose' in the bore, which can cause it to spin or rattle. Engineers must specify the maximum installation diameter on the assembly drawing to prevent technicians from using excessive force.