Methodology to carry out an analysis of damage caused by wear of blades of axial compressor on a marine gas turbine

Abstract

The objective of this research was to reduce cost of maintenance in this equipment. Analysis on a blade of gas turbine was performed, which was in operation on an offshore platform. Compressor blade was exposed to a severe damage by the impact of particles and environmental pollutants such as salts, sands and sulphurs. In first stage of this analysis, a visual inspection with a borescope was effected. Images analysis was used to determine the typical failure modes. A tribological characterization was carried out. Chemical composition of the material of blades was obtained. Scanning electron microscopy (SEM) was used to measure chemical properties and evaluate degradation of surfaces of blades after 30,000 service hours. The points, where there are the points in which failures take place. Results showed wear modes were originated by a severe stinging action. Also, large craters, similar to those observed in solid particle erosion, were developed by at normal impact. In the same way it could be found some localized areas with corrosion and irregular scratches like plowing action, was observed; these are the points in which failures take place.