Shakedown and Creep Rupture Assessment of a Header Branch Pipe Using the Linear Matching Method.

Many power plant components are subject to combined mechanical and thermal loading conditions during their operating lifetime. It is important that potential failure mechanisms of such components are extensively investigated in order to ensure sufficient confidence in their reliability. This paper presents shakedown and creep rupture analyses of a header branch pipe subjected to cyclic thermo-mechanical loading performed using the Linear Matching Method (LMM). The detailed investigation of failure mechanisms under the combined action of the internal pressure and the cyclic thermal load due to the temperature difference between the inner and outer pipe surfaces will be the primary focus of this paper. The header branch pipe considered here is composed of a single material with properties that are dependent upon both temperature and rupture life. A novel study investigating the effect that two geometric parameters – branch diameter and separation – have upon the failure mechanisms of the header branch pipe has also been carried out. The impact that these geometric parameters have upon the limit load, shakedown and creep rupture limits is one of the principal areas that is investigated in this work. In addition to this, an understanding of the dependency of the creep rupture limit upon the defined time to creep rupture is also studied. Verification of these results is then given by full elastic-plastic analyses performed within ABAQUS. [ABSTRACT FROM AUTHOR]

Copyright of Procedia Engineering is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)