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A study on the condition assessment of large diameter water valves using non-destructive technologies

비파괴 기술을 이용한 대구경 수도용 밸브의 상태평가에 관한 연구

  • Ho-Min Lee (K-water Research Institute, Korea Water Resources Corporation) ;
  • Hyun-yong Choi (K-water Ulsan Local office, Korea Water Resources Corporation) ;
  • Suwan Park (Department of Civil & Environment Engineering, Pusan National University) ;
  • Tae-min Oh (Department of Civil & Environment Engineering, Pusan National University) ;
  • Chae-Min Kim (K-water Research Institute, Korea Water Resources Corporation) ;
  • Cheol-Ho Bae (K-water Research Institute, Korea Water Resources Corporation)
  • 이호민 (한국수자원공사 K-water연구원) ;
  • 최현용 (한국수자원공사 울산권지사) ;
  • 박수완 (부산대학교 사회환경시스템공학과) ;
  • 오태민 (부산대학교 사회환경시스템공학과) ;
  • 김채민 (한국수자원공사 K-water연구원) ;
  • 배철호 (한국수자원공사 K-water연구원)
  • Received : 2023.06.13
  • Accepted : 2023.07.26
  • Published : 2023.08.15

Abstract

In this study, non-destructive technologies that can be applied to evaluate the integrity of valve materials, safety against internal pressure caused by corrosion, and the blocking function of large-diameter water valves during operation without requiring specimen collection or manpower entering the inside of the valve were tested to assess the reliability of the technologies and their suitability for field application. The results showed that the condition of the graphite structure inside the valve body can be evaluated directly through the optical microscope in the field without specimen collection for large-diameter water butterfly valves, and the depth of corrosion inside the valve body can be determined by array ultrasound and the tensile strength can be measured by instrumented indentation test. The reliability of each of these non-destructive techniques is high, and they can be widely used to evaluate the condition of steel or cast iron pipes that are significantly smaller in thickness than valves. Evaluation of blocking function of the valves with mixed gas showed that it can be detected even when a very low flow rate of mixed gas passes through the disk along with the water flow. Finally, as a result of evaluating the field applicability of non-destructive technologies for three old butterfly valves installed in the US industrial water pipeline, it was found that it is possible to check the material and determine the suitability of large-diameter water valves without taking samples, and to determine the corrosion state and mechanical strength. In addition, it was possible to evaluate safety through the measurement results, and it is judged that the evaluation of the blocking function using mixed gas will help strengthen preventive response in the event of an accident.

Keywords

References

  1. Cho, Y., Jung, G., Park, S. and Kim, J. (2004). A study on a crack evaluation technique for turbine blade root using phased array ultrasonics, J. Korean Soc. Nondestruc. Test., 24(2). 151-157.
  2. Jeon, E., Park, J. and Kwon, D. (2003). The optimization of experimental conditions of continuous indentation test for tensile properties evaluation, Korean J. Metal. Mater., 41(2). 83-89.
  3. Korea Water and Wastewater Works Association. (2016). A Manual of Water Valve Maintenance. M-009.
  4. Lee, H., Choi, T., Park, J. and Bae, C. (2022). Structural safety evaluation of decrepit gray cast iron water valves for the control of water supply, J. Korean Soc. Water Wastewater. 36(5). 261-273.
  5. Lee, K., Choi, M., Kim, J., Kim, K. and Kwon, D. (2006). Instrumented indentation technique: new nondestructive measurement technique for flow stress-strain and residual stress of metallic materials, J. Korean Soc. Nondestruc. Test., 26(5). 306-314.
  6. Ministry of Environment. (2021). A Manual of Waterworks Network Facility Maintenance.
  7. Park. S., Ahn, Y. and Gil, D. (2012). The study of measurement of residual stress for pipe weldments of power plant, J. Korean Weld. Join. Soc., 30(2). 120-125.
  8. Paun, M. (2005). Control Valve Handbook. 5th edition. Emerson Automation Solutions.
  9. Shin, H.J., Song, S. and Jang, Y.H. (2000). Nondestructive inspection of steel structures using phased array ultrasonic technique, J. Korean Soc. Nondest. Test., 20(6). 538-544.
  10. Skousen, P.L. (2011). Valve handbook. McGraw-Hill Education.
  11. Song, W., Kim, S., Ahn, H., Kim, K. and Kwon, D. (2013). A study of utilizing instrumented indentation technique for evaluating in-field integrity of nuclear structures, J. Korean Soc. Nondestruct. Test., 33(2). 165-172.
  12. Yoon, B., Kim, Y. and Lee, J. (2013). Development of the phased array ultrasonic testing technique for nuclear power plant's small bore piping socket weld, J. Korean Soc. Nondestruct. Test., 33(4). 368-375.
  13. Zappe, R.W. (1999). Valve selection handbook. Gulf Professional Publishing.