摘要
埋地天然气管道在使用过程中环焊缝处由于各种原因容易产生裂纹,导致管道失效。对某天然气管道的开裂段取样,进行宏观形貌检查、微观断口分析及化学成分检测。结果表明,断裂管段材料中Cr含量较标准要求值偏低,且开裂位置存在未焊透缺陷是天然气管道开裂的主要原因。有限元分析结果表明,管道材料在应力载荷及腐蚀的共同作用下,管道环焊缝未焊透处将产生裂纹,该裂纹会随时间增加而不断扩展,最终导致管道失效。建议在管道的实际运行过程中,要加强监测并做好预警措施,避免因泄漏导致事故的发生。
During the application, some cracks easily appear in the circumferential weld of the buried gas pipeline due to various reasons, and it even leads to pipeline failure. Taking samples from some gas pipeline cracking section, macroscopic examination, micro fracture analysis, and chemical composition inspection were carried out. The results showed that the content of Cr in pipe materials is less than the specified value, and some incomplete penetration defects exist in cracking location, it is the main reason caused gas pipeline cracking. The finite element analysis results indicated that under the stress load alut corrosion, the cracks will appear in incomplete penetration location of pipeline circumferential weld, which will extend with time going on, and finally lead to pipeline failure. In the actual operation process of pipeline, it shouhl strengthen monitoring and early precaution measures, and avoid aeeidents caused by pipeline leakage.
出处
《焊管》
2013年第9期58-61,共4页
Welded Pipe and Tube
基金
河北省质量技术监督局项目(编号:2011ZD17)
关键词
管道
焊缝
未焊透
裂纹断口
微观分析
有限元
pipeline
weld
incomplete penetration
cracking fracture
micro analysis
finite element
