Existing labyrinth seals on a Fluid Cat Cracker (FCC) wet gas compressor train were proving unreliable and challenging to control. Leaking H2S was creating a hazardous environment for maintenance personnel. The refinery needed a better solution.
Client Challenge:-
The labyrinth seals on both LP and HP multistage centrifugal compressors were performing significantly below customer expectations while H2S leakage through the seals meant that personnel working around the compressor had to wear respirators and associated PPE. The seals were also unreliable in operation and limited instrumentation made it difficult to control the gas supply and monitor seal performance.
The compressor OEM was unable to deliver an effective service response or solution. As a result, the customer was inclined to seek an alternative solution.
Our Response:
- Evaluate the condition and performance of the existing seals on both LP & HP compressors
- Review compressor operation and operating environment
- Provide an inspection report c/w photographic evidence and insight into reliability issues and H2S leakage
Recommendations/Work Scope:
- Replace existing seals with Kaydon K-MRC Multi-Ring Circumferential Seals
- Design to allow direct retrofit to the compressor
- Seal specification to eliminate H2S leakage
- Supply new instrumentation to enable control of gas supply and monitoring of seal performance.
Benefits:
- Seal installation required no compressor modification
- Reliability delivering uninterrupted performance between 7-yearly service intervals
- H2S leakage eliminated allowing unencumbered maintenance. No requirement for respirators
- New instrumentation monitors flow to and from seal providing real-time monitoring of seal health
- Responsive, high-quality seal support
For more details on this case study, or to discuss how we can help with repair, maintenance and support for your high-dependency mechanical seals, contact us.