Ultimately, the Oring material shears and flows into the socalled extrusion gap, and the seal fails Dynamic applications can hasten seal extrusion But even in static applications, high pressure can stretch assembly bolts and open the extrusion gap sufficiently to permit leakageOrings are bidirectional seals, circular in shape and cross section Orings are generally made of an elastomeric material, but may be made of other materials such as PTFE or metal An Oring seals through the deformation of the seal material by installation and media pressure to close off the gap between mating componentsWhat is Oring squeeze The squeeze is a ratio of the amount of deformation applied to the seal expressed as a percentage of the freestate crosssectional thickness Deforming the seal crosssection "energizes" the elastomer matrix much like compressing a spring;
Elastomer O Ring Seals Vs Omniseal Spring Energized Seals A Comparison