K-BRS bushing ring seal
An intermediate step between labyrinth seals and the K-CBS circumferential seal design are bushing ring seals, typically manufactured in carbon materials. These clearance seal designs are applied in main shaft seal applications as well as barrier seals. Commonly applied when the cost of higher buffer gas flows is not a concern, or in barrier seal applications for dry gas seals when there is adequate separation between the dry gas seal cavity and bearing such that oil contamination of the dry gas seal is not a concernS
Example of a K-BRS bushing ring seal applied as a barrier seal for a centrifugal compressor with dry gas seals in a natural gas pipeline application.