US Patent 8096559 Rotary seals

Seal assemblies are herein discussed. The seal assemblies can have a stiff backing ring supporting a seal ring, which is positioned adjacent an inner seal ring. In preferred embodiments, the inner seal ring is made from a material that enables the inner seal ring to absorb media particles in situ to change its particle density. This allows the seal assembly to form wearable surfaces on the fly to decrease wear on the seal ring.