Mechanical Behavior of an Industrial Gas Turbine underFault Conditions, a Case History

[摘要] The resolve of journal bearing field problems and the full vibrational assessment of an industrial gas turbine, simple cycle rotor train, ABB’s GTllN2 is presented. Three unitsexperienced several times damage of the journal bearings on the compressor end. Theanalysis of the damage, including tests, indicated that insufficient jacking oil flow was thecause. The jacking concept was corrected and starting history has proven reliable operation,resulting in not one additional failure.During the same period, two last stage blades failed in one of the units damagingneighboring blades additionally. The machine tripped under the unbalance. Some auxiliarypiping and the babbitt of the journal bearing was damaged. However, the rotor came to a safe stop with only some rubbing, and the turbine casing fulfilled its containment functionperfectly.In order to better understand the dynamic behavior of the train, an extensive vibrationmeasurement program was decided between Kentucky Utilities and ABB, and executedby Bently Nevada. The results proved excellent rotor balance, verified original designparameters, and no fluid induced instabilities were found. This joint effort allowed to fullyassess and prove the rotor dynamic integrity of the gas turbine.

[学科分类] 力学，机械学