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During operation, natural gas pipelines come into direct contact with the medium being transported inside their walls. The medium transported includes not only natural gas but also hydrogen sulfide, dissolved oxygen, carbon dioxide, hydrates, and other substances. The presence of these impurities, along with changes in transmission pressure, temperature, and flow rate, can cause severe corrosion of the inner walls of long-distance natural gas pipelines. The main reasons can be specifically listed as follows: ① Long-distance natural gas pipelines are characterized by large transport capacities and long transmission distances; during transportation, they must operate in high-temperature and high-pressure conditions. However, such conditions increase the activity of acidic gases, thereby causing rapid corrosion of the inner walls of the gas pipelines ； ②When natural gas is transported through pipelines, a free liquid phase appears. Under normal circumstances, three states – gas, liquid, and solid – coexist within the pipeline. These three phases, when in motion, cause corrosion of the inner wall of the pipeline; especially at the bends in the pipeline, the wall thickness becomes thinner, making it very easy for natural gas leaks to occur ； ③Under certain conditions, pipelines suffer from chemical and electrochemical corrosion caused by impurities in natural gas, which mainly include hydrogen sulfide, carbon dioxide, and water.