Design procedures for high temperature components using finite element methods

A procedure for design and redesign of high temperature components is developed. The thesis begins with a description of an engineering problem, namely the failure of a steel plant pre-reduction kiln, which incorporates a number of commonly occurring design problems. A redesign procedure, which follows a more prescriptive rather than a descriptive method, is established for the case study. An investigation of the material properties, loading conditions and component failure is undertaken. Each investigation begins with an overall view of the topic, which is then narrowed to suit the case study. The procedure developed during the investigations begins by using conventional theoretical techniques to determine the material properties and loadings involved. Simple and then more detailed finite element modelling establishes more accurate results for so.me complicated problems. In particular the thermal loading of the kiln is found to be considerably larger than the self weight loading. Failure analysis techniques together with a sophisticated non-destructive testing technique, Holographic Interferometry, are employed to investigate flaws and failure modes. The technique developed enables the qualification and quantification of material properties and flaws for in situ components. The dominant failure mode for the kiln is stress corrosion which can be prevented by avoiding corrosion and lowering the thermal stresses. However the existence of flaws enables fatigue failure to occur. The procedure continues with a life assessment due to fatigue, however in the kiln case study, the validity of this is uncertain due to insufficient test data. Recommendations for redesign are then given. The design procedure enables an ordered and effective means of solving in situ component failure and redesign problems.

Grantor dc:publisher.institution

Department of Mechanical Engineering

Year dc:date.issued

1993

Author dc:creator

• Hulett, Cameron

Advisor dc:contributor.advisor

• Penny, R K

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/14306

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/14306