보일러튜브 용접부 비파괴검사를 위한 컴퓨터화 방사선투과시험 적용 연구

Application of Computed Radiography for Nondestructive Testing of Boiler Tube Weldments

  • 박상기 (한전 전력연구원 원자력발전연구소) ;
  • 안연식 (한전 전력연구원 원자력발전연구소) ;
  • 길두송 (한전 전력연구원 원자력발전연구소)
  • 발행 : 2009.10.31

초록

A steam generator (boiler) in thermal power plants, consisting of more than 30,000 parts and components, can lead to the plant shutdown with damage to even the small part of the components; esp., like weld failures on boiler tubes. Consequently it is greatly demanded to improve the quality of the weld on the boiler tube for the stable operation of the power plants. Because of the feature of the welding, which is done past by melting the work pieces and adding a filler material that cools to become a strong coalescence, there is a great possibility that weld failures take place. As a result, it is regulated to make a non-destructive testing, like radiography test, to detect defects and flaws in the weld. The current film radiography test provides a lower image quality exceeding 2.0% of a basic quality level for a penetrameter, it is very likely to fail to detect micro defect. As a result, the prevention for the boiler tube failure has not been made effectively. In this study, computed radiography technology has been applied as a digital radiography test to the boiler tube weld, and Se-75 radiation source was used to improve the image quality, instead of Ir-192 source. As a result of this study, it is proven to save the time and cost for test and to enhance the quality level of penetrameter penetrating image, which enables to upgrade the quality of radiography test to the boiler tube weld.

키워드

참고문헌

  1. Tateno, Linuma and Takano, 1987, Springer-Verlag, "Computed Radiography", Chapter 3, Image reading: Conversion to digital signal, pp. 18-20.
  2. Computerised Information Technology Limited, England, 2007, "DR1400 Digital Radiography System Training Book", Chapter 6, p. 6.
  3. American Socity for Nondestructive Testing, 2006, "Nondestructive Testing Handbook", Volume 4, Radiographic Testing Third Edition, Selection of Radiographic Source pp. 74-78.
  4. Lee Sung Shik, Im Sung Jin and Han Hyen Soo, 2001, "Development Radiography Testing Method for Using Se-75", The Korea Society For Nondestructive Testing, Spring Science Meeting Book, pp. 40 - 46.
  5. Park Sang Ki and Lee Yeang Ho, "The Study on Image Sensitivity Evaluation for Digital Radiography Image", Journal of the Korea Society for Power System Engineering, Vol. 12, No.6, pp. 70-77.