THERMAL SCIENCE

International Scientific Journal

REMAINING LIFE ASSESSMENT OF A HIGH PRESSURE TURBINE CASING IN CREEP AND LOW CYCLE SERVICE REGIME

ABSTRACT
Thick walled components such as high pressure (HP) steam turbine casings operating under high parameter conditions are subjected to a complex stress state. As a result of that stress state, some parts of HP turbine casing undergo to the creep fatigue caused by the combination of thermal fatigue resulted from repeated start/stop operation and the creep which occurs during long-term operation at high temperature and high-pressure. It is well known that domestic thermal power plants have been in use over 100000 h which means that significant cost is required not only for maintenance, but often for renewal of equipment. Based on comprehensive investigation, the results of residual life assessment of one high pressure steam turbine casing, which belongs to the older turbine generation, taking into account simultaneous action of thermal fatigue and creep, are presented in this paper. Also, the critical flaw crack size of HP turbine casing is determined because this parameter has a strong influence on casing integrity and residual life. The results of residual life assessment provide not only a basis for further maintenance, but also estimated time for reparation or renewal.
KEYWORDS
PAPER SUBMITTED: 2012-12-19
PAPER REVISED: 2013-03-24
PAPER ACCEPTED: 2013-09-29
PUBLISHED ONLINE: 2014-07-06
DOI REFERENCE: https://doi.org/10.2298/TSCI121219179B
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2014, VOLUME 18, ISSUE Supplement 1, PAGES [S127 - S138]
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© 2019 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence