Annular Seal Grooves Prevent Extrusion in High-Pressure Compressors

The fluid absorption problem is mitigated by segmenting the seal into multiple smaller O-rings rather than one large O-ring. Each smaller O-ring absorbs less fluid, reducing the cumulative blisting risk while maintaining sealing effectiveness across the entire circumference.

Backup rings are introduced as intermediary elements between the O-rings and the expansion gap. These backup rings act as barriers that prevent fluid-saturated O-rings from contacting each other and failing, allowing the system to tolerate fluid absorption without catastrophic failure.

The groove configuration segments the potential extrusion path into isolated sections. Each O-ring is confined to its own groove, so even when the casing expands and creates gaps, the O-rings cannot extrude into the expansion space because the grooves act as physical barriers containing each seal element independently.

The design accepts that casing expansion will create gaps, but converts this potentially harmful effect into a benign condition by providing backup rings that fill the expansion gap. The gap that would normally cause extrusion is instead filled with inert backup ring material that prevents O-ring contact and failure.