Formation and progression of cavitation erosion surface for long exposure

Cavitation erosion often causes the leakage of water in piping systems of industrial plants. Cavitation erosion tests were carried out for S15C carbon steel equivalent to pipe steel STPG370 in a stationary specimen test method using a vibratory apparatus specified by ASTM G32-03. Another test was performed using a cavitating liquid jet method according to ASTM G134-95 to simulate the flow condition. It was found that the maximum depth of erosion (MaxDE) increases with exposure time with a power of about 0.5 which is different from the ordinary power of 1.0. The distribution of the maximum depth of erosion pits was obtained by the extreme value analysis (Gumbel distribution) at every exposure time.