Degradation of the cast steel parts working in power plant pipelines

• Autorzy: Renowicz D. , Hernas A. , Cieśla M. , Mutwil K.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Purpose of this paper is to identify the influence of loading history and the processes of material degradation on the initiation of cracking and on durability under creep and fatigue conditions. Design/methodology/approach: The aim of the research was to identify the properties of the material of the fittings cut out of a start-up pipeline connecting two OP-140 boilers with turbines, as well as to identify the reasons of failure of these parts after 100000 hours of operation. Results of the investigations were the basis of predicting the lifetime of machine parts and components of devices subjected to complex mechanical and thermal influence. Numerical simulation of work conditions was also performed. Problem of life assessment of the pipelines is currently the object of interest of many research centers. Findings: Due to extreme conditions of the start-up pipeline operation, its T-connections are subject to quick wear, and their properties determine the operational reliability and safety of the whole pipeline. For the reason it is necessary to verify the criteria of pipelines’ durability evaluation applied so far, based on the parameters characteristic of the creep process exclusively. Research limitations/implications: In the case discussed, i.e. a T-connection being a start-up pipeline part, the present criteria should be expanded with critical values describing fatigue/corrosion processes. Practical implications: The paper introduces the results of investigations of the 0.2C-1.2Cr-0.6Mo-0.3V cast steel used for parts of live steam pipelines working in power plants. Such parts include, e.g. T-connections. Originality/value: The paper show the possibilities of numerical models application.

Słowa kluczowe

EN

fatigue; creep-resistance; working properties of materials and products; erosion

PL

zmęczenie; odporność na pełzanie; własności eksploatacyjne; erozja

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 219--222
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Renowicz D.

• Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland

autor

Hernas A.

• Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland

autor

Cieśla M.

• Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland

autor

Mutwil K.

• Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland

Bibliografia

• [1] J. Okrajni, K. Mutwil, M. Cieśla, Chemical pipelines material fatigue, Journal of Materials Processing Technology 164-165 (2005) 897-904.
• [2] M. M. Cieśla, K. Mutwil, M. Wojas, Constructional and material conditions of cracking processes of parts of pipelines operating in the chemical industry, Material Engineering No. 3-4 (1999) 186-192, (in Polish).
• [3] J. Okrajni, K. Mutwil, M. Cieśla, T. Skibiński, Durability of pipelines subjected to mechanical and thermal interactions, Energetic No. 7, 2003, 447-452 (in Polish).
• [4] ASME B31.1-1995 Edition, An American National Standard, ASME Code for Pressure Piping, B31.
• [5] PN-79/M-34033 Steam and water pipelines. Calculation of pipe wall thickness. Polish Committee For Standardization And Measures, 1979, (in Polish).
• [6] PN-EN 12952-3:2002 (U) Water-tube boilers and auxiliary installations – Part 3: Design and calculation for pressure parts. 2002.
• [7] H. Sehitoglu, Thermal and Thermomechanical Fatigue of Structural Alloys, Fatigue and Fracture, Vol. 19, ASM Handbook, 527-556, 1996.
• [8] D. Renowicz, M. Cieśla, W. Essler, Investigation of crack initiation in steels under thermo-mechanical fatigue conditions. 20 th Symposium of Fatigue And Cracking Mechanics, Bydgoszcz, Pieczyska 2004, 347-354, (in Polish).
• [9] H. Kuhn, D. Medlin, ASM Handbook, Mechanical Testing and Evaluation V 8, ASM International 2000.
• [10] A. Hernas, J. Dobrzański, Durability and fatigue of steam boiler and turbine parts. Silesian University of Technology Publishing House, Gliwice 2003 (in Polish).
• [11] J. Dobrzański, A. Hernas, Relationship Between Microstructure and Residual Life-Time of Low Alloyed Cr-Mo Steels, Publ. by IMechE., London, C494/079, 1996 451-461.
• [12] G.A. Webster, R.A. Ainsworth, High Temperature Component Life Assessment, Chapman & Hall, London 1994.
• [13] A.J. Fookes, D.J. Smith, Using a strain based failure assessment diagram for creep-brittle materials, in: Proceedings of the Second International HIDA Conference, Stuttgart 2000.
• [14] D.W. Dean, R.A. Ainsworth, S.E. Booyh, Development and use of R5 procedures for the assessment of defects in high temperature plant, in: Proceedings of the Second International HIDA Conference, Stuttgart 2000.
• [15] I.A. Shibli, Overview of HIDA Project in: Proceedings of the Second International HIDA Conference, Stuttgart 2000.