Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Assessment of Creep Damage on a High Temperature Pipe Bend of 0.5Cr0.5Mo0.25V Ferritic Steel for Thermal Power Plant

화력발전소용 0.5Cr 0.5Mo 0.25V 강 곡관배관의 크리프 손상평가

  • 현중섭 (한국전력공사 전력연구원 수화력발전연구소) ;
  • 허재실 (한국전력공사 전력연구원 수화력발전연구소) ;
  • 김봉수 (한국전력공사 전력연구원 수화력발전연구소)
  • Published : 2010.03.01
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Abstract

Components in thermal power plants are subjected to service conditions under which creep damages take place causing material exhaustion. Comprehensive creep damage investigations have been performed on a 0.5Cr0.5Mo0.25V pipe bend which had been taken out of service after 117,603h and 501 start-ups because of severe cracks. The propagation of creep damage in a long term exposed pipe bend has been analysed by the replication, Indentation and hardness tests. Also, Calculation of creep lifetime has been investigated in order to verify actual lifetime of a damaged pipe bend. By measuring diametrical expansion, Accumulated creep strain and creep strain rate were calculated. Calculated results of creep lifetime on the Larson-Miller Parameter method are good agreement with actual service-exposed hour.

Keywords

References

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