Answer
In applications subject to heavy vibration or impact (e.g., jackhammers or racing engines), the orientation of the spiral ring's end gap relative to the primary vibration axis is critical. If the vibration is perpendicular to the gap, the inertia of the ring ends can cause them to 'chatter' against the groove, leading to fretting wear and eventually widening the groove. The preferred orientation is to have the gap aligned with the direction of the highest acceleration. For spiral rings, the 'gap' is actually the space between the ends of the coiled wire. Because spiral rings have 360-degree contact (unlike circlips which have a large gap), they are inherently more resistant to vibration, but ensuring the ends are tucked into the groove is still paramount to prevent dislodgement.
