Abstract: An abeyance seal includes a polymer actuation ring, which defines a flexible sealing lip normally spaced from the shaft. When subjected to leakage, this element collapses against the shaft and forms an initial sealing. Secondarily, a metal sealing/anti-extrusion ring provides a second seal during leakage. The polymer ring provides the initial sealing function during leakage at low differential pressure, and once the polymer ring seals to the shaft, increased sealed pressure loads the polymer ring against the metal sealing/anti-extrusion ring causing it to deform so that the metal ring comes into contact with the shaft to form a second seal.

Abstract: An abeyance seal includes a polymer actuation ring, which defines a flexible sealing lip normally spaced from the shaft. When subjected to leakage, this element collapses against the shaft and forms an initial sealing. Secondarily, a metal sealing/anti-extrusion ring provides a second seal during leakage. The polymer ring provides the initial sealing function during leakage at low differential pressure, and once the polymer ring seals to the shaft, increased sealed pressure loads the polymer ring against the metal sealing/anti-extrusion ring causing it to deform so that the metal ring comes into contact with the shaft to form a second seal.