Cracks on the Roots of Turbine Blades of the Low-Pressure Turbine in a Steam Power Plant
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E. Plesiutschnig
Abstract
Cracks were found in the roots of steam turbine blades of the third blade row (LA-2) of the low-pressure turbine during revision works in a coal-fired power plant. Metallographic examinations reveal pitting corrosion sites, branched cracks, and local plastic deformation at the root of the first load bearing flank radius. The fracture surface was analyzed using light microscopy and scanning electron microscopy (SEM). Finite element (FE) simulations were performed in order to qualitatively represent the stress peak positions on the blade root.
Kurzfassung
Bei Revisionsarbeiten eines Kohlekraftwerkes wurden in der Niederdruckturbine Fußrisse an den Dampfturbinenschaufeln der 3. Laufreihe (LA-2) entdeckt. Metallografische Untersuchungen zeigen Positionen mit Lochkorrosion, verzweigte Risse und lokale plastische Verformung am Fuße des ersten Tragflankenradius. Die Bruchfläche wurde mit Lichtmikroskopie und Rasterelektronenmikroskopie (REM) analysiert. Finite Elemente (FE) Simulationen wurden durchgeführt, um die Positionen der Spannungsspitzen am Schaufelfuß qualitativ darzustellen.
References / Literatur
[1] Huang, Y.; Zhang, F.; Hwang, K.; Nix, W.; Pharr, G.; Feng, G.: A model of size effects in nano-indentation, J. Mech. Phys. Solids, vol. 54, no. 8, pp. 1668–1686, Aug. 2006. 10.1016/j.jmps.2006.02.002Suche in Google Scholar
[2] Wild, E.: Beanspruchungsbedingte Gefügeänderungen von ferritisch-perlitischen Stählen am Beispiel des Rad-Schiene-Kontaktes, Technische UniversitätBerlin, 2008.Suche in Google Scholar
[3] Bramfitt, B.; Benscoter, A.: Metallographer's guide: practices and procedures for irons and steels. ASM International, 2002, p. 80.10.31399/asm.tb.mgppis.9781627082587Suche in Google Scholar
[4] Petzow, G.: Metallographisches, keramographisches, plastographisches Ätzen. Borntraeger, 1994, p. 298.Suche in Google Scholar
[5] Bürgel, R.: Festigkeitslehre und Werkstoffmechanik, 1st ed.Wiesbaden, Germany: Vieweg & Sohn Verlag/GWV Fachverlage GmbH, 2005, p. 237.10.1007/978-3-322-82040-2_1Suche in Google Scholar
[6] Mundt, G.; Neidel, A.; Matijasevic-Lux, B.: Moving Blade Failure in the Low-Pressure Turbine of a Steam Turbo Set, Pr. Metallogr., vol. 12, pp. 782–791, 2012. 10.3139/147.110204Suche in Google Scholar
[7] EffertzP.; Forchhammer, P.: Die Lochkorrosionsanfälligkeit des Vergütungsstahles X20Cr 13 in Natriumchloridlosungen, Mater. Corros., vol. 816, pp. 809–816, 1977. 10.1002/maco.19770281202Suche in Google Scholar
[8] Pfennig, A.; Zastrow, P; Kranzmann, A.: Corrosion Behavior of Differently Heat Treated Steels in CCS Environment with Supercritical CO2,”Energy Technol. 2014 Carbon Dioxide Manag. Other Technol., no. 35, 2014.Suche in Google Scholar
[9] Cerit, M.; Genel, K.; Eksi, S.: Numerical investigation on stress concentration of corrosion pit, Eng. Fail. Anal., vol. 16, no. 7, pp. 2467–2472, Oct. 2009. 10.1016/j.engfailanal.2009.04.004Suche in Google Scholar
© 2015, Carl Hanser Verlag, München
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Editorial
- Editorial
- Technical Contributions/Fachbeiträge
- Heat Treatment-Induced Improvement of the Thermal Shock Resistance of Si3N4 Tools for Metallurgical Applications
- Imaging Structural Damage of Bacteria on Antibacterial Copper – a Scanning Electron Microscopy Study Using FIB Cross-Sectioning
- Cracks on the Roots of Turbine Blades of the Low-Pressure Turbine in a Steam Power Plant
- Meeting Diary/Veranstaltungskalender
- Meeting Diary
Artikel in diesem Heft
- Contents/Inhalt
- Contents
- Editorial
- Editorial
- Technical Contributions/Fachbeiträge
- Heat Treatment-Induced Improvement of the Thermal Shock Resistance of Si3N4 Tools for Metallurgical Applications
- Imaging Structural Damage of Bacteria on Antibacterial Copper – a Scanning Electron Microscopy Study Using FIB Cross-Sectioning
- Cracks on the Roots of Turbine Blades of the Low-Pressure Turbine in a Steam Power Plant
- Meeting Diary/Veranstaltungskalender
- Meeting Diary
