摘要
天然气管道的自保护药芯半自动多层多道焊接工艺的环焊缝易发生失效,主要原因是焊接层数少于焊接工艺要求值、单道焊层厚度过厚、不符合施焊原则等,导致焊接热输入过高,影响焊缝组织,从而致使环焊缝韧性指标下降。选取采用自保护药芯焊丝半自动焊施工工艺的X80管线钢为研究对象,通过对不同焊接层数的环焊缝区及热影响区韧性试验结果、金相组织及断口进行对比分析,结果表明:随着焊接层数的增加,焊缝的冲击韧性大幅提升且分散性下降;断口形貌的韧性比例增大;晶粒不断细化且彼此交错,可有效预防裂纹扩展。研究结果对于制定天然气管道焊接工艺规程、加强施工现场质量管理具有指导作用。
The girth welds of natural gas pipelines applied by self-shielded flux cored semi-automatic welding process in multiple layers and passes are prone to failure,and the main reasons include the number of welding layers is less than that required by the process,the single-pass welding layer is too thick,and welding principles are not met.These problems can cause excessive input of welding heat,which affects the weld structure and leads to the decline of girth weld toughness.Hence,the study was performed based on the X80 pipeline steel by the semi-automatic welding process using the selfshielded flux cored wire.Specifically,the toughness test results,metallographic structure and fracture of the girth weld zone and heat affected zone with different welding layers were analyzed comparatively.The results show that,with the increase of welding layers,the impact toughness of weld is greatly improved and the dispersion is reduced,the toughness ratio of fracture morphology increases,the grains are continuously refined and staggered with each other,which can effectively prevent the crack propagation.Generally,the research results could play a guiding role in formulating the welding procedure specification of natural gas pipeline and strengthening the quality management of construction on site.
作者
王婷
陈健
沙胜义
戴联双
杨鹏
赵小辉
WANG Ting;CHEN Jian;SHA Shengyi;DAI Lianshuang;YANG Peng;ZHAO Xiaohui(PipeChina North Pipeline Company;China Oil&Gas Pipeline Network Corporation;College of Materials Science and Engineering,Jilin University)
出处
《油气储运》
CAS
北大核心
2022年第4期404-410,共7页
Oil & Gas Storage and Transportation
基金
国家管网集团公司重大专项“高钢级管道缺陷检测评价技术研究”,WZXGL202104。
关键词
X80管线钢
环焊缝
焊接层数
韧性
失效
X80 pipeline steel
girth welds
welding layers
toughness
failures
