Gas Seal Failures Caused by Axial Vibrations

Case StudyThis case study describes the root cause investigation of 12 dry gas seal failures in three integrally geared centrifugal compressors over a period of 12 years. These compressors are in fuel gas booster service, supplying a 500 MW gas turbine combined cycle power plant. The root cause investigation determined that the dry gas seal failures were the result of a design integration problem in which the rotor-bearing system exposed the dry gas seals to both excessive axial displacement and excessive axial vibrations. These problems were resolved by redesigning the rotor-bearing system to incorporate thrust bearings on the pinion