Pitting Corrosion Damage for Prediction Useful Life of Geothermal Turbine Blade

Cuevas-Arteaga C¹, Rodriguez JA^1, , Clemente CM¹, Rodríguez JM² and Mariaca Y¹

¹Centro de Investigación en Ingeniería y CienciasAplicadas, (CIICAp), UAEM, Cuernavaca, Morelos, Mexico

²Centro Nacional de Investigación y Desarrollo Tecnológico

Cite this paper:
Cuevas-Arteaga C, Rodriguez JA, Clemente CM, Rodríguez JM and Mariaca Y. Pitting Corrosion Damage for Prediction Useful Life of Geothermal Turbine Blade. American Journal of Mechanical Engineering. 2014; 2(6):164-168. doi: 10.12691/ajme-2-6-3

Abstract

In the last years, the power industry in México has suffered the consequences of some mechanisms of damage that reduce the efficiency in power generation. These mechanisms of damage originate problems in main components as rotors, nozzle blades and others due to losses of pressure, high vibrations, erosion and corrosion. By the type of work fluid, mixture of water-steam and brine rich in salts, geothermal turbines are in a high corrosion environment. The main forms of damage caused by corrosion in a geothermal turbine are crevice corrosion and pitting corrosion. The latter is a damage mechanism through which the useful life is affected. The blades of the last stage in low pressure (LP) in the geothermal turbines are exposed to corrosion by environment and high load cycles which cause failures by corrosion fatigue, crack initiation and crack propagations. In this work, a methodology for the analysis of the failure by pitting corrosion and its consequences in its useful life was obtained. From the results, it is possible to conclude that this corrosion may influence a mechanism of pitting corrosion, which precedence to stress corrosion cracking and corrosion fatigue.

Keywords:
pitting corrosion blades of geothermal turbine useful life damage mechanisms

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References:

[1]	Valdéz B and Schorr M. (2013). Corrosionand preservation of industrial infrastructure.
[2]	Mazur Z, García R, Aguirre J and Pérez N. (2008). Steam turbine blade failure analysis.Engineering Failure Analysis, 15 (1-2), pg 129-141.
[3]	González G and Kubiak J. (2004). Diagnóstico, estimación de vidaremanente y asistenciaparaimplementarcorrecciones de lasfallas de los álabesdelúltimopaso de lasturbinasgeotérmicas de 110 y 37.5 mw.
[4]	Rodríguez JA, Clemente CM., Cuevas Arteaga C., Segura JA, Urquiza G, Y.El. Hamzaoui. (2012). Estimation of useful life in turbines blades with cracks in corrosive environment. ICEFA V - Fifth International Conference on Engineering Failure Analysis.
[5]	Hyo J. (1998). Fatigue failure analysis of last stage blade in a low pressure steam turbine. Engineering Failure Analysis, vol. 6 pp 93-100.
[6]	Otakar J and Machemer L. (2008). Steam turbine corrosion and deposits problem and solutions.Pproceedings of the thirty – seventh turbomachinery symposium.
[7]	Zhang XY , Li SX , Liang R , Akid R. (2013).Effect of corrosion pits on fatigue life and crack initiation. 13th International Conference on Fracture. Beijing, China.
[8]	Zhou S and Turnbull A. (1999).Influence of pitting on the fatigue life of a turbine steel. Fatigue FractEngng Mater Struct, vol. 22pp 1083-1093.
[9]	Dooley RB. (2007). Development of model to predict stress corrosion cracking and corrosion fatigue of low pressure turbine components
[10]	Sankaran KK, Perez R, Jata KV. (2001). Effects of pitting corrosion on the fatigue behavior of aluminum alloy 7075-T6: modeling and experimental studies, Materials Science engineering, vol. A297 pp 223-229.
[11]	Rajasankar J, Nagesh R. Iyer. (2006).Probability-based model for growth of corrosion pits in alluminium alloys, Engineering Fracture Mechanics, vol. 73 pp 553-570.
[12]	DuQuesnay DL, Underhill PR, Britt HJ (2003).Fatigue crack growth from corrosion damage in 7075-T6511 aluminium alloy under aircraft loading. International Journal of Fatigue, Vol. 25, 371-377.
[13]	Instruction Manual Model RFB-200: Rotating beam Fatigue testing Machine.
[14]	Standard test method for measurement of fatigue crack growth rates ASTM E647-88A (American Society for Testing and Materials, 1988).
[15]	Harlow DG and Wei RP. (1998). A probability model for the growth of corrosion pits in aluminum alloys induced by constituent particles, Engineering Fracture Mechanics, Vol. 19-3, pp 305-325.
[16]	Tada H, Paul C. Paris, George R. Irwin. (2005).The stress analysis of crack handbook, Third edition, ASME, New York.
[17]	Shi P and SankaranMahadevan. (2001) Damage tolerance approach for probabilistic pitting corrosion fatigue life prediction. Engineering fracture Mechanics. 1493-1507.
[18]	Grosvenor AP, Kobe BA, McIntyre NS. (2005).Activation energies for the oxidation of iron by oxygen gas and water vapour, Surface Science, Vol. 574, pp 317-321.
[19]	Carpinteri A, Paggi M. (2007). Are the Paris’ law parameters dependent on each other, In: Proceeding of the congesso IGF19, Milano, 2-4.