Life span prediction for the last row blade of steam turbine


Department of Mechanical Engineering, Islamic Azad University, Shoushtar Branch, Iran


The steam turbine of Ramin Ahvaz power plant is a k300-240 model manufactured by the Russian power machine company, which has six units of 300 MW. The above turbine has a rotational speed of 3000 rpm; its final blade weight is 9.2 kg. Its centrifugal force causes one of the most important and effective stresses in the blade.
In this research, the first step, the forces acting on the blades such as centrifugal force are investigated, and then the stresses of these forces are calculated. By using these calculations and the properties of the blades, estimation of the blade life is made by applying stress-life correction coefficients. In the following, by using an engineering software named ABAQUS, a sample of the last row of fins is simulated. This simulated specimen after meshing is stress analyzed. By this method, the results of manual computations are compared by using different life criteria such as Goodman's and Gerber's life criteria results obtained by Abacus (finite element software). Finally, we evaluate the validity of the previous steps through the manufacturer's documentation.


[1] Kostyuk.A,G. “Steam and Gas Turbine”. University of Water and Power Industry. 2: pp. 376-407. 1988.
[2] Arkan, H., “Stress Evaluation of Low Pressure Steam Turbine Rotor Blade and Design of Reduces Stress Blade”, Engineering. Tech, pp. 169-180. 26(1),2007.
[3] P. Vaisshaly, B.S.V. Ramarao., “Finite Element Stress Analysis of a Typical Steam Turbine Blade”. International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064.
[4] Shigley, J.E., Mischke, C.R., and Budynas, R.G. Mechanical Engineering Design 7th ed. McGraw-Hill Companies, New York. 2004.
[5] Joseph,M ,”Mechanical Behavior of Engineering Materials”, Prentice-Hall, Englewood Cliffs, pp.224 ,1962.
[6] G.R. Mahmodi, Growth cracks and fracture of the steam turbine blade, pp.88-136, Ahwaz: Pajohanegan Rah Danesh, 2016. (In Persian)
[7] Mestanek,P., “Low cycle fatigue analysis of a last stage steam turbine Blade” , Applied and Computational Mechanics pp. 71-82.,2(1), 2008.
[8] Riger,N.F.andSalzman, R.N. ,”Application of a crack –Closure Model for Turbine Life Assesment”, 34 thConfrance of Turbomachinery Symposium , Houston, pp.1-21. TX, 2005.
[9] loveleen, K.B. ,Pardeep,G.,and Vikas,R., “Fractograghic investigations of the failure of L-1 low pressure steam turbine blade”. Case Studies in Engineering Failure Analysis 172-78.2013.
[10] Kumar, s., Roy, n. J., and Ganguli, R., “Monitoring low cycle fatigue damage in turbine blade using vibration characteristics”, Mechanical system and singnal processing, pp. 480-501. 21(1), 2005.
[11] Sakurai,S.and Isobe ,N. ,”Life assessment for creep and fatigue of steam Turbine”,Transactions of the Indian Institue of Metals,63(2-3) ,pp.281- 288 ,2010.
[12] James ,M.,Newby,M. ,and Hatting ,D. ,”Shot Peening of Steam Turbine Blades”,Fatigue,2(1) pp.441-451. , 2010.
[13] Shirani, M., Härkegård, G.,” A review on fatigue design of heavy section EN-GJS-400- 18-LT ductile iron wind turbine castings”, energyequipsys, pp. 5-24., Vol 2, 2014.
[14] Jhaa, P., Das, B., and Rezaie, B., ” Significant factors for enhancing the life cycle assessment of photovoltaic thermal air collector ”, Energy Equip. Sys,  Vol. 7, No. 2, PP.175‐197., June 2019.
[15] Mousavia, S, M., Nejat, A,. and Kowsary, F,. ” Optimization of turbine blade cooling with the aim of overall turbine performance enhancement  ”, Energy Equip. Sys,  Vol. 5, No. 1, PP. 71-83., March 2017.