The Research Of Water-Cut Oil Pipeline Internal Corrosion Evaluation And Corrosion Prevention Technology In Changqing

This article sums up the rules of pipeline corrosion,the measures of the present anti-corrosion and the current situation of nonmetallic pipelineapplication by making a large number of field research about the corrosion of the surface gathering and transferringsystem,the long-distance pipeline,and the water injection system pipeline in Changqing Oilfield.Using the ultrasonic pulse detection method,residual thickness of pipelinewas tested to judge the corrosion of the buried pipeline on service.Besides,corrosion experimentswere done on HCC in antisepsis and polymer alloy pipe both inthe laboratory and field.Compared with the experiments result that pipe without HCC andusing normal metal pipe respectively,application effects were analyzed.Adaptation evaluation was also made of the anticorrosion pipe material.And the high economic efficiency and adaptability of pipe is concluded byanalyzing the anticorrosion performance,price,transportation,installation and loading & unloading.It is pointed out that Changqing Oilfield pipeline internal corrosion is more serious than external corrosion.The maximum corrosion thickness loss rate is 2.6% ~ 49.0% and the maximum pitting rate is 0.03 ~ 0.7 mm/a.The effective measures for pipeline anticorrosion are the anticorrosive coating and using nonmetallic pipe.The overall online internal lining anticorrosion technology can effectively protect the steel pipeline.Compared with the glass steel tube,this technology couldsave the cost about 15% ~ 30% when a new pipeline is built and the investment needed for replacing old pipeline is only 1/4 ~ 1/6 of that purchasing a new pipeline.The application prospect is promising.Besides,the polymer alloy lining pipeline has good corrosion resistance and the HCC integral anti-corrosion lining pipe has obvious advantages because of the low price,easy carrying and unloading and maintenance mode,compared with nonmetallic pipes.