The Stray Current Corrosion And Protection Of The Gas Transmission Main Line In Sichuan-Chongqing Ring Network

As the lifeblood of the current world industry,oil is essential for the safe and stable transportation of oil and natural gas.At present,the most important means of oil and gas transportation is through underground metal pipeline transportation.With the development of science and technology,electrified railways,high-voltage transmission lines and other facilities have gradually increased,which will cause stray currents to interfere with the pipeline,thus causing corrosion and damage to the pipeline.The rapid development of science and technology in Sichuan-Chongqing region,Chengdu-Shantou High-speed Railway,Neijiang-Kunming Railway,and the "four DC" high-voltage transmission lines and other facilities were completed and put into use.The number and intensity of stray current interference sources continued to increase,resulting in Sichuan-Chongqing ring network transmission.The disturbing corrosion of mains is getting worse.Based on this,this paper makes a study on the corrosion and protection of stray currents in the gas pipelines in the Sichuan-Chongqing ring network.The main work of this dissertation is as follows:(1)Analyze the corrosion mechanism of stray current from the reasons of stray current generation,corrosion principle and corrosion hazard,and lay the theoretical foundation of this paper;(2)From stray current The causes of corrosion,corrosion principles,distribution patterns,detection methods,protection methods,and other aspects,analysis of stray current research status and current problems in Sichuan and Chongqing in the field;(3)investigate and analyze Chuanxiong ring gas transmission The general corrosion status of main lines,combined with the corrosion principle of stray currents and the harms they cause,conducts specific research on the corrosion of some typical pipes in the pipe network;(4)Research and adaptability to commonly used testing instruments in Sichuan and Chongqing area.Analyze,use the appropriate instrument to carry on the concrete test and result analysis to the typical pipeline that suffers different interference,and put forward the suggestion of corrosion protection accordingly;(5)According to the actual situation of the typical pipeline,focus on the drainage protection of the main gas pipeline in Sichuan-Chongqing ring network.Make researches to evaluate the drainage systems currently used in some pipelines and provide recommendations for drainage schemes for some pipelines Opinions.The research results show that:(1)The three kinds of commonly used stray current detectors belong to the general level,the detection accuracy is not high,and the functions are not complete.However,due to its economical efficiency,it is suitable for the actual situation in the Chuanyu region,so it can be satisfied for the time being.Demand,but urgently needed further innovation.(2)The Naian line was disturbed by stray currents with mainly moderate DC interference.The Tianxin ?219 pipeline was simultaneously subjected to high-intensity and long-lasting DC and AC interference,and the different areas of the pipeline near Chengdu-Chengdu high-speed railway were subject to different degrees.The stray currents are disturbed,and are exacerbated with the increase in the high-speed train start-up density and the simultaneous load.(3)The drainage protection scheme of Weiqing Double Line has basically achieved effective discharge of stray currents.In addition,this article combined with the typical segment of the Na'an Line to further supplement the discharge protection of the Sichuan-Chongqing ring gas transmission main line.(4)From the aspect of maintenance cycle,testing content,personnel training,and daily inspection data,four technical management proposals for the Sichuan-Chongqing ring gas transmission line were proposed.In a word,through the actual detection and analysis of several typical pipelines,this article provides a detailed protection scheme for the stray current corrosion of the Sichuan-Chongqing ring gas transmission main line,which ensures the safe and stable operation of the gas pipeline network in the Sichuan-Chongqing area.