1989 年 38 巻 430 号 p. 823-828
Extreme value statistical analysis has been applied for estimating corrosion loss of carbon steel pipes and tanks, in which leakage due to corrosion was found.
In the cases of erosion at elbows in sulfuric acid and corrosion at gas cooling tubes used for heat transfer, a good coincidence between the measured and the estimated depth by the extreme value analysis was achieved if the population of samples was divided into the following two groups: the heavily corroded area and the other area before the analysis. For oil tank plates which showed uniform corrosion with a constant corrosion rate, the population of samples could be analyzed as a whole and the return period could be set as large as 10000. A grouping method was proposed for analyzing a large number of point data which were measured according to the Fire Service Act for oil tank base plates corroded by local penetration of rain in the outside boundary.