Journal of Applied Reliability (한국신뢰성학회지:신뢰성응용연구)

The Korean Reliability Society (한국신뢰성학회)
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Comparative Reliability of Nondestructive Testing for Weld: Water Wall Tube in Thermal Power Plant Boiler Case Study

용접부 비파괴 검사의 신뢰성 비교: 화력 발전소의 보일러 수냉벽 배관 사례연구

  • 최창덕 (삼영검사엔지니어링) ;
  • 임익성 (남서울대학교 산업경영공학과)
  • Received : 2018.08.15
  • Accepted : 2018.09.10
  • Published : 2018.09.25
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Abstract

Purpose: The purpose of this research is to find which technique, between the PAUT (Phased array ultrasonic test) that has been used widely in practice and RT (Radiographic test) that was used widely in the past, has the higher reliability as a non-destructive testing of welding points in water wall tubes. Methods: To evaluated the reliability of non-destructive testing, eleven test pieces that were fabricated intentionally, which have the most frequently occurred defect types in water wall tubes and then both the PAUT and RT were performed on those eleven test pieces to compare their reliability. Results: The differences of type of defect, length are occurred due to the characteristics of nondestructive testing. The RT could not detect the lack of fusion defect type in specimen #4 and #8 while PAUT could not detect the lateral crack and 1 mm size small porosity in specimen #11. Conclusion: It is concluded that applying both the RT and PAUT result the best reliability rather than applying only one test method, if it is possible, in nondestructive testing of weld water wall tube in thermal power plant boiler case.

Keywords

References

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