Ailate s back-up ring BRT has no intended sealing function. Instead, as their name indicates, they are protective and supporting elements made from extrusion-resistant materials which generally have a rectangular cross section.They are installed in a groove together with an elastomeric sealing element preferably with a corresponding O-ring in static applications.
Due to the tight fit of the Back-up ring in the housing, they prevent extrusion of the pressurised elastomeric sealing element into the sealin gap.