中俄东线天然气管道焊接消磁技术试验

长输管道在建设、改线或维抢修作业时,常会遇到管道对口处有磁偏吹现象,使得在焊接施工时,电弧发生偏离,导致焊接缺陷甚至无法焊接施工,严重影响了工程进度及管道的本质安全。中俄东线天然气管道工程采用1422 mm口径、X80钢级管道,以往所采用的消磁方法和消磁设备已无法满足其大口径、高钢级管道的消磁作业。通过分析管道剩磁的产生机理和影响因素,得到不同消磁方法对中俄东线管道的适用性。通过现场试验验证直流消磁法,分析直流消磁和直流焊机消磁的优缺点及工作参数,提出可行性建议。

Test on the degaussing technology used in the welding of China-Russia Eastern Gas Pipeline

During the construction,rerouting and maintenance&repairing of long-distance pipelines,the phenomenon of magnetic partial blowing often occurs at pipeline junctions,which leads to the deviation of electric arc in the process of welding operation.As a result,welding defects appear and even the welding operation cannot be carried out,so as to seriously impact the progress of the project and the essential security of the pipeline.OD 1422 mm and X80 steel grade pipeline is used in the China-Russia Eastern Gas Pipeline Project,and the degaussing methods and degaussing devices used in the past are unable to satisfy the degaussing requirements of large diameter and high steel grade pipelines.In this paper,the applicability of different degaussing methods to the China-Russia Eastern Gas Pipeline was clarified by analyzing the generation mechanisms and influencing factors of pipeline remanence.After DC degaussing method was verified by conducting field tests,DC degaussing and DC welder degaussing were analyzed from the aspects of advantage,disadvantage and working parameters.In addition,the feasible recommendations were proposed.