Journal of Energy Engineering (에너지공학)

The Korean Society for Energy (한국에너지학회)
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Risk Assessment Technique for Gas Fuel Supply System of Combined Cycle Power Plants (II) : Based on Piping System Stress Analysis

복합화력발전의 가스연료 공급계통에 대한 위험도 평가 기법 연구 (II) : 배관 시스템 응력 해석을 이용한 위험도 평가

  • Yu, Jong Min (Graduate School, Department of Mechanical Engineering, Chung-Ang University) ;
  • Song, Jung Soo (Graduate School, Department of Mechanical Engineering, Chung-Ang University) ;
  • Jeong, Tae Min (Graduate School, Department of Mechanical Engineering, Chung-Ang University) ;
  • Lok, Vanno (Graduate School, Department of Mechanical Engineering, Chung-Ang University) ;
  • Yoon, Kee Bong (Department of Mechanical Engineering, Chung-Ang University)
  • 유종민 (중앙대학교 대학원 기계공학과) ;
  • 송정수 (중앙대학교 대학원 기계공학과) ;
  • 정태민 (중앙대학교 대학원 기계공학과) ;
  • 럭 완노 (중앙대학교 대학원 기계공학과) ;
  • 윤기봉 (중앙대학교 기계공학부)
  • Received : 2018.05.28
  • Accepted : 2018.06.07
  • Published : 2018.06.30
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Abstract

The combined cycle power plant has a cycle of operating the gas turbine with fuel, such as natural gas, and then producing steam using residual heat. The fuel gas is supplied to the gas turbine at a level of 4 to 5 MPa, $200^{\circ}C$ through a compressor and a heat exchanger. In this study, the risk assessment method considering the piping system stress was carried out for safe operation and soundness of the gas fuel supply piping system. The API 580/581 RBI code, which is well known for its risk assessment techniques, is limited to reflect the effect of piping stress on risk. Therefore, the systematic stress of the pipeline is analyzed by using the piping analysis. For the study, the piping system stress analysis was performed using design data of a gas fuel supply piping of a combined cycle power plant. The result of probability of failure evaluated by the API code is compared to the result of stress ratio by piping analysis.

복합화력발전 플랜트는 천연가스와 같은 연료로 가스 터빈을 작동시킨 후 잔류 열로 증기를 생산하는 사이클을 가지고 있다. 연료가스는 압축기 및 열교환기를 통해 4~5 MPa, $200^{\circ}C$ 수준의 상태로 가스터빈에 공급된다. 본 연구에서는 가스 연료공급 배관계통의 안전 운영 및 건전성 확보를 위해 배관 시스템 응력을 고려한 위험도 평가 기법 연구를 수행하였다. 위험도 평가 기법으로 잘 알려진 API 580/581 RBI 코드에서는 위험도에 배관 응력의 영향을 반영이 제한적이다. 따라서 배관 해석을 이용하여 배관의 시스템적 응력을 위험도의 파손확률로써 인자화하는 접근법을 제시하였다. 해석은 가상 발전 플랜트의 가스연료 공급 배관의 설계 데이터에 근거하여 배관 시스템 응력 해석을 수행하였다. API 코드에 의해서 평가된 파손확률 등급과 배관해석을 이용한 응력비 평가 결과를 비교하였다.

Keywords

References

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