Stainless steel pipelines in water supply systems must be thoroughly cleaned during operation to prevent microbial corrosion
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This post was last edited by Wang Wei2 on 2024-1-30 at 10:29. It is essential to clean stainless steel pipes in water supply systems regularly to prevent microbial corrosion. Example: The pipes in a closed-loop water supply system were made of 304L stainless steel with a diameter of 50 mm; corrosion pits had penetrated the pipe walls, along with some small pinholes. The failure mode is typical microbial corrosion (MIC). Bacterial testing of the corroded area revealed Gallionella. Analysis: During construction, a leak in an isolation valve allowed brine to enter the system ； Additionally, the system was once started by injecting untreated well water. The mixture of well water and saltwater remained in the pipes for some time, introducing chlorides and corrosive bacteria. Bacteria initiate local corrosion cells on the inner surface of the tube. Due to chloride concentration caused by bacteria and the low pH at the bottom of the pits, corrosion continues to progress, leading to pipe perforation.
Improper cleaning of stainless steel pipes in water supply systems during operation can lead to microbial corrosion. For example, there is a closed-loop water supply system that uses 304L stainless steel pipes; leakage in the isolation valves allowed saline water to enter the system, and untreated well water was injected into it during startup – factors that led to the introduction of chlorides and bacteria. Erosion pits and pinholes are the result of microbial corrosion (MIC), and Acieromonas jiaxiensis was detected. These bacteria form local corrosion cells inside the pipes, causing the pH level at the bottom of the corrosion pits to drop and chlorides to concentrate, ultimately leading to pipe perforation. .