Official Answer
Answer
Heavy-duty spiral rings have a larger radial wall $b$ and thickness $t$, which increases their stiffness $k_{radial}$. In deep-groove applications, the ring must be expanded or contracted significantly to clear the shaft or bore before reaching the groove. The force required for installation increases with $b^3$. If the stiffness is too high, the 'Mandrel' method may require hydraulic assistance. Additionally, deep grooves can lead to 'Ring Trapping' where the ring is difficult to remove during teardown because the removal notch is recessed too far. Designers must ensure the removal notch remains accessible and that the installation stresses do not exceed $0.8 imes S_y$.
