Long-term creep rupture strength prediction and failure mechanisms of welded joints of boiler tubes and pipes

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F25870807%3A_____%2F16%3AN0000014" target="_blank" >RIV/25870807:_____/16:N0000014 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Long-term creep rupture strength prediction and failure mechanisms of welded joints of boiler tubes and pipes

Popis výsledku v původním jazyce

Operating life and reliability of steam boiler and piping systems are considerably determined by long-term creep rupture strength (CRS) of welded joints of boiler tubes and pipes. Consequently, the appreciable research effort has been focused to reveal the most important factors affecting the creep properties of weldments. The presented work deals with the evaluation of creep rupture strength of welded joints in steam boiler piping system made from low-alloy and chromium modified steels. Cross-weld creep rupture tests and, at the same time, comparative creep tests of parent material are considered as the optimum approach how to evaluate the decreasing of creep resistance of weldment towards the base metal and how to quantify this effect e.g. by using strength reduction factor (SRF) and lifetime reduction factor (LRF) of welded joints. The necessary condition for such an approach is that the mechanism of creep damage (type IV cracking) in laboratory tests must be the same that acts in in-plant welded joints of the mentioned steels. The obtained results confirmed that the precipitation strengthened steels (mainly Cr-Mo-V type) show more pronounced decreasing of creep rupture strength of the critical locality of welded joint – intercritical part of heat affected zone when compared to Cr-Mo steels and that they are, therefore, much more prone to the premature failure.

Název v anglickém jazyce

Long-term creep rupture strength prediction and failure mechanisms of welded joints of boiler tubes and pipes

Popis výsledku anglicky

Operating life and reliability of steam boiler and piping systems are considerably determined by long-term creep rupture strength (CRS) of welded joints of boiler tubes and pipes. Consequently, the appreciable research effort has been focused to reveal the most important factors affecting the creep properties of weldments. The presented work deals with the evaluation of creep rupture strength of welded joints in steam boiler piping system made from low-alloy and chromium modified steels. Cross-weld creep rupture tests and, at the same time, comparative creep tests of parent material are considered as the optimum approach how to evaluate the decreasing of creep resistance of weldment towards the base metal and how to quantify this effect e.g. by using strength reduction factor (SRF) and lifetime reduction factor (LRF) of welded joints. The necessary condition for such an approach is that the mechanism of creep damage (type IV cracking) in laboratory tests must be the same that acts in in-plant welded joints of the mentioned steels. The obtained results confirmed that the precipitation strengthened steels (mainly Cr-Mo-V type) show more pronounced decreasing of creep rupture strength of the critical locality of welded joint – intercritical part of heat affected zone when compared to Cr-Mo steels and that they are, therefore, much more prone to the premature failure.

Druh

D - Stať ve sborníku

CEP obor

JG - Hutnictví, kovové materiály

OECD FORD obor

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Projekt

<a href="/cs/project/LO1203" target="_blank" >LO1203: Regionální materiálově technologické výzkumné centrum - Program udržitelnosti</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

25. ročník mezinárodní konference metalurgie a materiálů METAL 2016

ISBN

978-80-87294-67-3

ISSN

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e-ISSN

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Počet stran výsledku

6

Strana od-do

753-758

Název nakladatele

Tanger s.r.o.

Místo vydání

Brno

Místo konání akce

Brno

Datum konání akce

1. 1. 2016

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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