Patent ID: 11873830
Assignee: JOHN CRANE UK LIMITED
Field: Mechanical elements (Mechanical engineering)
Classification: CPC F | IPC F

Claim 8:
9. A dry gas seal to seal process gas in a compressor that includes a rotating shaft, the dry gas seal comprising:
a first stage seal including:
a first mating ring that can be coupled to the rotating shaft to rotate with the rotating shaft;
a first primary ring that forms a first seal interface with the first mating ring;
a first retainer ring that can be fixedly attached to the compressor; and
a first carrier ring moveably coupled to the first retainer ring, the first carrier ring including a first primary ring carrying face attached to the first primary ring, a first carrier ring rear face and a first carrier ring sealing surface extending between the first primary ring carrying face and the first carrier ring rear face;
a first sealing element disposed between the first retainer ring and the first carrier ring;
wherein the first carrier ring sealing surface includes an oleophobic coating disposed thereon and that exposed to sealing gas at a pressure that is higher than a pressure of gas in the compressor, and wherein the first sealing element slides along the oleophobic coating and relative to the first carrier ring as the first carrier ring moves relative to the first retainer ring;
and

a second stage seal including:
a second mating ring that can be coupled to the rotating shaft to rotate with the rotating shaft;
a second primary ring that forms a second seal interface with the second mating ring;
a second retainer ring that can be fixedly attached to the compressor; and
a second carrier ring moveably coupled to the second retainer ring, the second carrier ring including a second primary ring carrying face attached to the second primary ring, a second carrier ring rear face and a sealing surface extending between the second primary ring carrying face and the rear face;
wherein the first carrier ring sealing surface includes an oleophobic coating disposed thereon.