Corrosion And Control Of Stray Current On Buried Pipeline Of Kaiyuan Gas Company

Chongqing Kaiyuan gas company by the Jingkai road to the Yuanyang station of the pipeline and rail transit line 3 parallel,the rail transit power supply system prone to current leakage,the current flow into the soil to form stray current,adjacent to the buried pipeline by stray current interference prone to electrochemical corrosion,since the light rail has been put into operation,the pipeline has been a number of leakage incidents,corrosion is not optimistic.In this paper,The research objective is with the rail transit line 3 parallel section pipeline.and the monitoring of the ground potential and the soil potential gradient is carried out.Based on the analysis of the type and disturbance degree of the stray current disturbance,the influence of stray current variation and stray current on the corrosion of pipeline and its influencing factors were studied by using indoor simulation experiment.Then put forward the stray current protection measures for Kaiyuan gas company.Designed experimental factors influence simulation device of stray current,the influence of different external disturbance intensity,horizontal distance between buried pipeline and track traffic,buried depth of buried pipeline and damage area of buried pipeline anticorrosion layer on stray current of buried pipeline are studied respectively.The corrosion behavior of the stray current to the pipeline is studied by the soil embedding method.The corrosion morphology and the product are analyzed according to the scanning electron microscopy and the energy spectrum,to determine the orbital line running on the stray current generated by the buried gas pipeline corrosion mechanism.The physical and chemical analysis of the soil samples in the depth of the field gas pipeline was carried out.The soil simulation liquid was prepared according to the physical and chemical analysis data.The natural corrosion potential and polarization curve of the pipeline steel in the presence of stray current were tested by electrochemical method.,then analyzed the variation law of the electrolytic corrosion performance of the pipeline.Aiming at the dynamic stray current generated by rail transit line3,the indoor simulation experiment device was designed and designed to study the effect of different factors on the corrosion rate of pipeline steel in the presence of stray current by accelerating the corrosion weightlessness test.The test of the poor analysis method to determine the main influencing factors.According to the variation law of stray current and the main influencing factors of pipeline corrosion rate,established the model of stray current prevention and control measuresfor rail transit,and evaluated the control effect by numerical simulation software.Finally,combined with the actual situation for the Kaiyuan gas company pipeline to select the feasible stray current control measures.