Improvement of plant reliability based on fusion of prediction and inspection of wall thinning of piping due to FAC
Early detection and prediction of flow-accelerated corrosion(FAC)on major piping systems and application of suitable countermeasures such as water chemistry improvements are essential for preventing pipe rupture in aged NPPs.There are generally two approaches to evaluating and preventing future FAC occurrence; one is based on inspection and the other on prediction or estimation.The fusion of the prediction and inspection procedures can lead to effective and reliable preparation against FAC occurrence and propagation.An FAC code based on analysis of materials and water interaction can be applied for FAC risk evaluation for the entire plant systems to point out the locations where future pipe defects might occur,their time margins and their hazard scales and to prepare for continuous pipe inspections and early implementation of suitable countermeasures.As a result of V&V evaluation of the FAC code,it was confirmed that the code could prepare for the wall thinning rate within a factor of 2.As a result of sensitivity analysis of major FAC parameters,it was pointed out that the effects of flow turbulence showed the largest contribution to the uncertainty of wall thinning rate estimation.The prediction can contribute to select the important location for inspection,while the inspection can contribute to improve the prediction based on wall thinning date,which may result in increasing plant reliability.The fusion of the prediction and inspection procedures is demonstrated in the presentation.
plant reliability risk evaluation FAC prediction inspection uncertainty analysis
Shunsuke Uchida Hidetoshi Okada Masanori Naitoh M.Kojima H.Kikura
Institute of Applied Energy,Tokyo,Japan Tokyo Institute of Technology,Tokyo,Japan
国际会议
沈阳
英文
56-67
2017-09-26（万方平台首次上网日期，不代表论文的发表时间）