Creep rate assessment in function of stress and temperature for P91 steel

• Autorzy: Osocha P. , Duda P.
• Języki publikacji: EN

Abstrakty

EN

Many coal-powered power stations uses equipment that have worked for over 20 years. Farther operation of the units involve large costs due to efficiency and reliability loss. Predicting the residual life of elements that have been in service for many years is especially important, when existing installations can not be replaced for economical or technological reasons. Accurate residual life assessment is the key for optimization of expenses due to unscheduled outages and unnecessary replacements. For power stations’ elements operating in high temperatures for very long time, understanding and mathematical description of creep phenomena is of utmost importance. It allows on FEM modeling of the elements behavior in time and assessment of worn degree. This paper presents methods for a creep strain and rate modeling. The main aim is to prepare an equation modeling creep rate of P91 steel in function of time, stress and temperature based on test data. For this reason, a creep phenomenon will be presented together with significant equations. Then, sample calculations, leading to the creep rate model establishment, will be performed. The paper finishes with the presentation of the equation describing the creep rate of P91 steel in dependence on time and stress and temperature.

Słowa kluczowe

EN

steam boilers; pressure vessels; creep modeling

• Wydawca: Wrocław University of Technology, Department of Periodics Publications
• Czasopismo: Journal of Energy Science
• Rocznik: 2012
• Tom: Vol. 1, nr 2
• Strony: 71--82
• Opis fizyczny: Bibliogr. 8 poz., rys., tab.

Twórcy

autor

Osocha P.

• Cracow University of Technology, Faculty of Mechanical Engineering, al. Jana Pawła II 37, PL-31-864 Kraków, Poland

autor

Duda P.

• Cracow University of Technology, Faculty of Mechanical Engineering, al. Jana Pawła II 37, PL-31-864 Kraków, Poland

Bibliografia

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