Abstract:
There are different corrosion behaviors to Kushan oil pipeline due to various topographical ground features and soil distribution along the pipeline. Potential difference existed at different locations on the surface of buried pipeline is the major reason to cause metal surface corrosion. The article introduces a corrosive environment of the soil on the line and design, construction and test of Kushan oil pipeline's cathodic protection system which adopts impressed current and sacrificial anode for corrosion protection. In stonework segment with high resistivity, flexible auxiliary anode buried in the same ditch with the pipeline is used; in mountain segment, strip or block magnesium anode is used as sacrificial anode. The system operates normally during test period and shows a good result in application. The article puts forward that as high quality coatings with good properties is tend to be used for oil transporting pipelines in recent years, determination of the parameters such as coating's surface resistance and max. protective potential value shall be get through test. As the soil in most segments has high salinity, test on pipelin's protective potential shall be made frequently in rainy season.