The customer was unhappy with the performance of John Crane T-28 dry gas seals and was looking for an alternative option for seal inspection and repair services plus root cause failure analysis and advice for improved reliability.
Client challenge:-
When the seals on a Nuovo Pignone compressor were delivering lower than expected performance and the seal OEM’s service offer did not meet the requirements of the operator, the end user turned to NASH as Kaydon’s authorised agent and service centre for turbomachinery seals in the EMEA region in search of a more appropriate solution.
The goal was an alternate source for seal inspection and repair services for the John Crane T-28 and T-82 seals installed in the compressor.
Our response:-
- Evaluate both tandem gas seals and separation seals for condition and repair scope.
- Issue extensive report with photos and insight into failure cause.
- Discuss current operation of compressor and gas skid and comment on improvements.
- Design and manufacture seal test fixtures.
Recommendations:-
- Replacement of Type 82 separation seal assembly with Kaydon K-CBS.
- K-CBS assembly designed to fit existing seal cavity with existing hardware.
- Improved start-up procedures to reduce the risk of bearing oil migration through barrier seal.
- Improvement of seal gas filtration.
Work scope – Repair of T28 DGS included:-
- Replacing carbon face seal rings.
- Repairing balance diameter damage with hard nickel plating.
- Fabricate new test rig components for dynamic tests of T28 DGS.
- All tests per API 617 procedure.
Benefits:-
- Improved seal life and performance.
- Seals performing like new – or better.
- Repair costs significantly lower than the cost of seal replacement.
- Flexible, responsive and proven seal support for future requirements.