Patent ID: 8061984

Claim:
A sealing assembly configured to form a seal between a rotating shaft and a casing of a turbo machine having a high-pressure process gas, comprising: a housing defining a bore configured to receive the rotating shaft and sealing assembly, wherein the housing is mounted adjacent the casing; a high-pressure seal radially coupled proximate to an outer edge of the casing, wherein the high-pressure seal is configured to reduce the pressure of the high pressure process gas to a first pressure lower than the high pressure; a high-pressure labyrinth seal mounted longitudinally outward from the high-pressure seal and configured to partially restrict the flow of the process gas along the rotating shaft and separate the process gas from the high-pressure seal; a single dry gas blow-down seal mounted longitudinally outward from the high-pressure labyrinth seal and configured to blow down the process gas from the first lower pressure to a second pressure lower than the first pressure; a labyrinth seal mounted longitudinally outward from the single dry gas blow-down seal; a tandem dry gas seal mounted longitudinally outward from the labyrinth seal, wherein the tandem dry gas seal comprises a primary dry gas seal and a secondary dry gas seal axially spaced with an intermediate labyrinth seal; and a separation seal mounted longitudinally outward from the tandem dry gas seal.