Research On Cathodic Protection Technology Of Qing-ha Buried Oil Pipeline

Buried oil pipeline most with steel tube is given priority to, the soil physical andchemical properties of the in homogeneity of the metal material and the electrochemical inhomogeneity, constitute the electrochemical corrosion of buried pipelines conditions, and thesoil bacteria corrosion and stray current corrosion, long and large diameter metal pipe intounderground must suffer from serious corrosion. The Daqing oilfield has established a largediameter of the crude oil pipeline in extensive "coating protection is given priority to,cathodic protection for auxiliary joint protection method, after years of operation, part of thecrude oil pipeline of protective coating damage and aging cathode system such as theprotection of long-term owe factors, pipeline corrosion caused by increasing.This paper aiming at the Daqing oil field of oil pipeline corrosion status, taking the oilpipeline, a-represented an oil pipeline, and through the field test, indoor experiment, dataprocessing analysis methods for the polyurethane foam with PE anticorrosive thermalinsulation layer of buried oil pipeline corrosion mechanism of outside and law, the pipelineexisting cathodic protection system of testing analysis and evaluation of the optimization. Theresults of the study show that: Qing-ha pipeline corrosion is in the soil of the reduction ofoxygen corrosion process. Pipeline steel corrosion and corrosion speed from potential by soilhumidity and oxygen levels big effect. Along pipeline stray current, soil formation in thevarious corrosion macro battery and conveying sometimes also cause high pressure pipelinecorrosion of the main causes of the leak. Cathodic protection potential measurement methoddefect, pipe cathodic protection dead zone and metal structure of pipeline shielding, protectivecoating quality to the changes and the changes of soil environment can lead to cathodicprotection system failure. Cathodic protection according to various parameters should becomprehensive factors make corresponding adjustment, to control and decrease the pipelinecorrosion perforation, long-term and raise the replacement than electrode, the individuallocation and sacrificial anode, to strengthen the management of cathodic protection systemand monitoring of the optimization scheme.