New Repair Technologies for 7FA/FA+ Class Stage 1 Buckets

7FA/FA+급 1 단 버켓 위한 신정비기법 개발

The 1st stage bucket of the 170MW simple cycle gas turbine is one of the components that is normally run in exposed state at the highest thermally stressful environment while the turbine is operating. After certain period operation, various type of damages are easily found and the damages are identified as due to the turbine operating mode of which the demand of the electricity power is very peaking and cyclic. Since this trend is more evident at some part of power plants in Korea and it has caused higher scrap rate of the bucket at the first repair interval than other country. Therefore, demand for the higher capability and alternative technologies which allow salvaging more buckets and preventing from severe damages is always high. In this study, a review and estimation of the repair technologies for the past 5 years to present have been conducted and show results.