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dc.contributor.advisor | Van Rooyen, Gerrit T. | |
dc.contributor.postgraduate | Moggee, Herman | |
dc.date.accessioned | 2014-09-05T12:09:11Z | |
dc.date.available | 2014-09-05T12:09:11Z | |
dc.date.created | 1998-10-31 | |
dc.date.issued | 1998 | en_US |
dc.description | Dissertation (MEng)--University of Pretoria, 2014. | en_US |
dc.description.abstract | The repair welding of main steam pipelines, which involves the welding of new material onto service-exposed material, are investigated. This paper investigates the literature and experimental work surrounding this subject. The introduction provides a background to the applicable welding technology. In section two the heat-affected zone is discussed with emphasis on the residual stresses that develop in this zone. The mechanical properties of the heat-affected zone are also investigated. This includes the tensile, toughness and hardness properties as well as inspecting the relevant microstructures. The effect of post weld heat treatment on these properties is also investigated. Section three investigates the phenomenon of creep. Not only is this important due to the high temperatures at which these pipelines operate, but creep is also associated with some failures of these weld during post weld heat treatment. The creep properties of the heat-affected zone are investigated in detail with the use of weld simulation. Sections four and five detail reasons for weld failure after welding due to hydrogen and reheat cracking. Hydrogen cracking is investigated with the use of slow strain rate tensile tests during cathodical charging the specimen with hydrogen. The phenomenon of reheat cracking is investigated with the use of high temperature tensile tests as well as a novel approach in which the stress relief of a welded joint is simulated while measuring crack growth and stress relieved. | en_US |
dc.description.availability | Unrestricted | en_US |
dc.description.department | Materials Science and Metallurgical Engineering | en_US |
dc.description.librarian | gm2014 | en_US |
dc.identifier.citation | Moggee, H 1998, Susceptibility of creep aged material to stress relief cracking during repair welding, MEng dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/41936> | en_US |
dc.identifier.other | E14/4/562/gm | en_US |
dc.identifier.uri | http://hdl.handle.net/2263/41936 | |
dc.language.iso | en | en_US |
dc.publisher | University of Pretoria | en_ZA |
dc.rights | © 1998 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. | en_US |
dc.subject | Creep resistant material | en_US |
dc.subject | Reheat cracking | en_US |
dc.subject | Hydrogen cracking | en_US |
dc.subject | Stress relief | en_US |
dc.subject | Main steam pipeline repair weld | en_US |
dc.subject | UCTD | en_US |
dc.title | Susceptibility of creep aged material to stress relief cracking during repair welding | en_US |
dc.type | Dissertation | en_US |