Secondary seal for non-contacting face seals

摘要

A Non-contacting face type pressure sealing assembly for shafts rotating at high speeds, such as for example those of centrifugal compressors, such assembly having at least two mating sealing rings. One of the subject sealing rings is fixed to the rotating shaft. The other is non-rotating but typically biased by coil springs and allowed to slide within the seal housing in the axial direction. Non-rotating sealing ring is sealed at the housing by an arrangement of two elastomeric elements, one a sealing O-ring the other a compliant force transmitter. Compliant force transmitter can also be an O-ring or it can be an element triangular in cross-section. Angular contact between the two elements maintains transmission of the axial coil spring load towards the non-rotating ring, but also derives a radial load needed for low friction contact at the sealing O-ring.