Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Estimation of C(t) -Integral Under Transient Creep Conditions for a Cracked Pipe Subjected to Combined Mechanical and Thermal Loads Depending on Loading Conditions

열응력 및 기계응력이 작용하는 균열배관의 하중조건에 따른 천이 크리프 조건 C(t)-적분 평가

  • Received : 2010.08.20
  • Accepted : 2011.03.03
  • Published : 2011.06.01
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Abstract

There is a trend towards the progressive use of higher operating temperatures and stresses to achieve improved efficiencies in power-generation equipment. It is important to perform the crack assessment under hightemperature and high-pressure conditions. The C(t)-integral is a key parameter in crack assessment for transient creep states. The estimation of the C(t)-integral is complex when considering the mechanical and thermal loads simultaneously. In this paper, we study estimation of C(t)-integral under combined mechanical and thermal load depending on loading conditions.

최근 효율을 높이기 위한 플랜드의 환경이 고온, 고압으로 변화함에 따라 열하중과 기계하중을 동시에 반영한 균열 평가는 플랜트의 건전성을 위하여 반드시 필요하다. C(t)-적분은 고온 균열 평가에 있어서 천이 크리프 상태의 균열을 평가하는 중요한 요소이다. 열하중과 기계하중이 동시에 작용하는 환경에서의 C(t)-적분을 예측하는 것은 복잡하며 하중조건이 달라지는 경우에는 더욱더 복잡해진다. 본 논문에서는 열하중과 기계하중의 하중조건이 달라지는 여러 조건에 대한 C(t)-적분 평가식을 제시하였다.

Keywords

References

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