Estimation of corrosion rates for CUI in petrochemical plants using reliability

Currently, many plants in Japan have been operated for 30 years or more. Leakage accident in piping may occur because of CUI (Corrosion Under Insulation) progress in such a kind of plants. Proper maintenance should be performed because in the worst case inner fluid leakage might adversely affect human bodies or the environment. In the previous research, corrosion rates have been estimated based on cases of the past corrosion. However, the method of the previous research has some problems, such as the accuracy of estimation is insufficient. In this research, a selection support system which can estimate corrosion rates with high accuracy using reliability is developed.