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

The Korean Society of Mechanical Engineers (대한기계학회)
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Lateral Crush Strength of Nuclear Fuel Spacer Grid Considering Weld Properties

용접물성치를 고려한 핵연료 지지격자체 횡방향 충격강도

  • Received : 2012.05.21
  • Accepted : 2012.07.02
  • Published : 2012.12.01
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Abstract

A spacer grid, which is one of the structural components in a PWR fuel, is an interconnected array of slotted grid straps that are welded at the intersections to form an egg-crate structure. The spacer grid is required to have sufficient lateral crush strength to enable nuclear reactor shut-down during abnormal operating environments. Previous studies on the lateral crush strength analysis of the spacer grid were performed using only the base material properties. In this study, to investigate the effect of the lateral crush strength of the spacer grid when using the mechanical properties in the weld zone instead of the base material properties, lateral crush strength analysis by considering the mechanical properties in the weld zone as obtained from the instrumented indentation technique was performed, and the results were compared with those of previous studies.

가압경수로 핵연료의 구조부품인 지지격자체는 홈이 있는 격자 스트랩들을 끼우고, 끼워진 교차부위를 용접한 구조물이다. 원자로 비정상 운전중에 원자로의 긴급정지가 가능하도록 하기 위해 지지격 자체는 충분한 횡방향 충격강도를 갖도록 설계되어야 한다. 지지격자체의 횡방향 충격강도 해석에 대한 예전의 연구는 모재의 물성치만을 사용하여 수행되었다. 본 연구에서는 지지격자체 용접부에 모재 물성치를 사용하는 대신 용접물성치를 사용할 경우에 지지격자체 횡방향 충격강도에 미치는 영향을 조사하였다. 계장형 압입시험법으로부터 얻은 용접물성치를 용접부에 적용한 해석을 수행하였고, 그 해석 결과를 예전 연구결과와 비교하였다.

Keywords

References

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