Answer
When an internal spiral retaining ring is compressed for installation into a housing, it undergoes a 'wind-down' where the multiple turns of the spiral slide against each other. If the ring is over-compressed, the turns can overlap or 'nest' incorrectly, leading to a permanent reduction in the free diameter. This is mitigated by using a 'stop' on the installation tool to prevent compression beyond the point where the ring's OD is just slightly smaller than the housing ID. Additionally, the ring design should include a 'removal notch' or 'offset' that allows the turns to move freely without catching on one another. Proper lubrication during installation further reduces the friction between turns, ensuring the ring 'snaps' into the groove with full radial contact.
