I would like to ask everyone about the anti-corrosion issues of underground pipelines for storage and transportation
Thread Content
One raw material line runs underground. Corrosion protection was done properly, everything worked smoothly and it performed well in use; however, after 3 years, a problem kept occurring in one area, which was the tank area. In other words, why do the pipelines in our raw material line around the tank area keep leaking, while there are no problems in other areas?
There might be special corrosive substances underground in the tank area, or the anti-corrosion treatment for this area was not done properly in the past. Therefore, it is necessary to analyze what caused the leakage, how the leakage point was damaged, as well as the condition of the soil in that area and the status of surface water bodies.
There are many grounding points within the irrigation area, as well as a high amount of stray current, which can easily cause electrochemical corrosion to the pipelines.
Typical storage tanks are equipped with cathodic protection systems, and there is a difference in natural potential between the pipes and the tanks, which results in the formation of a corrosion cell between them. The pipes act as the anode, accelerating their own corrosion, while the tanks are protected.
Almost everyone says it’s electrochemical corrosion, but how can we explain the issue with the anti-corrosion coating?
It is obvious that the anti-corrosion layer did not fulfill its duties properly. The anti-corrosion layer is not firmly bonded to the substrate, or the pipe does not have an outer anti-corrosion coating