Technical Diagnostics and Non-Destructive Testing №2, 2018, pp. 3-15
Results of studying the causes for cracking in titanium alloy blades of steam turbines of K-1000-60/3000 TYPE
V.M. Torop1, O.V. Makhnenko1, G.Yu. Saprykina1, E.E. Gopkalo2
E.O.Paton Electric Welding Institute of the NAS of Ukraine, 11 Kazimir Malevich str., 03150, Kiev. E-mail: email@example.com
G.S.Pisarenko Institute for Problems of Strength of the NAS of Ukraine, 2 Timiryazevskaya str., 01014, Kyiv, Ukraine. E-mail: firstname.lastname@example.org
The paper presents the results of studying the causes for cracking in blades of the last stage of steam turbines K-1000-60/3000, operating in Ukrainian NPP. The main causes, physical essence of formation and accumulation of erosion damage of blade material surface as a result of high-velocity drop impact of overcooled steam still remain insufficiently studied. During performance of the work, a comprehensive study of the structure, chemical composition and mechanical properties of blade material was conducted. Morphological and fractographic investigations of the crack surface were performed. Proceeding from the results of these studies, conclusions were formulated on the causes of defects and the possibility of prediction of the residual life of blades. 9 References, 3 Tables, 23 Figures.
Keywords: erosion damage, cracks, steam turbine blade, morphological and fractographic studies, chemical composition, mechanical properties, titanium alloy TS5
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