Gas lubricated mechanical seal for turbo-compressor
28AT John Crane

Type 28 compressor dry-running gas seals have been the industry standard since early 1970 for gas-handling turbomachinery. Utilising John Crane's patented spiral groove pattern, these seals are non-contacting in operation.

During dynamic operation, the mating ring/seat and primary ring/face maintain a sealing gap of approximately 0.0002 in./5 microns, thereby eliminating wear.

These seals eliminate seal oil contamination and reduce maintenance costs and downtime.

Single, double opposed, and tandem cartridge seals are capable of handling a wide variety of gas sealing applications in the gas collection/transmission, refining, chemical and petrochemical processing industries.
Design Features

* Mating Ring
Shrouded mating ring prevents secondary damage in the event of a mating ring fracture.

*Leakage
Low-level leakage can be vented to a safe area, used as fuel to drive equipment, or returned to process via a low-pressure ejector.