January 2026, John Crane, a business of Smiths Group plc, announced the 50th anniversary of the breakthrough that changed the way gas compressors are sealed. This milestone demonstrates why dry gas seals have become the preferred choice for centrifugal compressors in the oil and gas and petrochemical industries.
Instead of using oil to seal like traditional systems, dry gas seals use a very thin gas membrane between the two seal faces. The spiral grooves on the rotating face create a lifting force so the two faces do not come into contact when the machine is running.
The seal consists of a rotating ring with grooves, a stationary ring, a spring that presses the two rings together when the machine stops, and auxiliary seals. Many machines use a tandem configuration consisting of a primary seal and a backup seal, along with a buffer seal to protect the bearing.
The fact that a sealing technology has continued to evolve over half a century shows that the need for reliability and reduced emissions is always present. Later improvements focused on groove shape, seal face materials, monitoring systems, and the ability to withstand more severe conditions.
When upgrading old compressors from oil seals to dry gas seals, it is necessary to carefully evaluate the quality of the supply gas, support systems, installation space, and operating conditions. Dry gas seals are not a solution for all compressors, but for high-pressure centrifugal compressors, they are often the preferred choice.
World Pipelines (22/01/2026). The article was compiled and reinterpreted by SNS-VN; brand names belong to their owners.