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Taking into account the aforementioned background related to DC interference-induced corrosion of buried steel pipelines and measures for protection against such interference, the typical DC interference cases that have been documented in China fall into the following categories: First, the stray current corrosion case involving the Northeast Crude Oil Pipeline. The Northeast Crude Oil Pipeline system has been in operation for over 40 years, during which 40 instances of corrosion-induced pipe failures have occurred; 80% of these were caused by DC stray current interference. In some sections of the pipeline that ran through areas with a high density of electrified railways, corrosion-induced pipe failures occurred as soon as half a year after burial, with a corrosion rate of 1–10 mm/year； There are also pipes running through asbestos mines, which developed perforations after just 3 years of being buried, with a corrosion rate of 2.0–2.5 mm/year. II. Cases of interference on external pipelines caused by cathodic protection in the oil and gas station area in the western region. The total DC current generated by the cathodic protection system in a crude oil station area in the western region reached 141 A. Even though the insulation joints within the station were in good condition, this resulted in significant DC interference over a range of 200–300 meters around the insulation joints of three oil transport pipelines outside the station. The potential of some sections of these pipelines shifted significantly, posing a high risk of local corrosion; furthermore, it prevented the cathodic protection system outside the station from functioning properly. III. Case of interference caused by the oil pipeline along the extension of Nanchang Metro Line 1: After the operation of the extension of Nanchang Metro Line 1 began, significant fluctuations occurred in the potential of a certain oil pipeline segment, K108–K129, which intersected its route. During daytime, when the metro was in operation, the potential of this segment fluctuated widely between -2.95V and -3.412V; in more than 10% of the segment, the potential when power was cut was above the values required by the protection standards, meaning the pipeline was under-proTECTED and at high risk of corrosion due to direct current stray currents. This issue was subsequently resolved by installing additional cathodic protection stations.