摘要
针对自保护药芯焊丝半自动焊接(FCAW-S)在高钢级管道环焊焊接中存在的问题,对在役高钢级管道焊口的力学性能进行了统计分析,并运用光学显微镜、扫描电镜、透射电镜、力学性能微测试和硬度云图等分析方法对焊缝组织和性能进行了综合分析。结果显示,焊缝填充焊层间链状M-A组织的分布形态、大小及析出物的大小和分布情况是引起焊缝韧性不稳定的主要因素;FCAW-S环焊接头的根焊强度和硬度远低于管体母材的强度和硬度,是整个环焊接头的薄弱环节。最后指出,X80管道应提高根焊焊材的强度,避免低强匹配引起应力集中。
Aiming at the problems of FCAW-S in girth welding of high grade pipeline,the mechanical properties of welded joint of high grade pipeline in service were analyzed.The microstructure and properties of the weld were analyzed by means of optical microscope,scanning electron microscope,transmission electron microscope,mechanical property microtest and hardness nephogram.The results show that the distribution and size of chain M-A structure and the size and distribution of precipitates are the main factors causing the instability of weld toughness.The root welding strength and hardness of FCAW-S girth welding joint are far lower than that of the base metal of pipe body,which is the weak part of the whole girth welding joint.It is pointed out that the strength of X80 pipe root welding material should be increased to avoid low strength matching.The stress concentration is caused by the stress distribution.
作者
齐丽华
王磊
杨耀斌
胡美娟
陈越峰
何小东
QI Lihua;WANG Lei;YANG Yaobin;HU Meijuan;CHEN Yuefeng;HE Xiaodong(CNPC Tubular Goods Research Institute,Xi’an 710077,China;State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials,Xi’an 710077,China;Petrochina West Pipeline Company,Urumqi 830013,China)
出处
《焊管》
2021年第6期7-12,共6页
Welded Pipe and Tube
基金
国家管网科研课题“高钢级(X80)管道环焊缝缺陷容限评估准则及关键技术研究”(项目编号GDXB22-2019-017)
国际焊接中心支撑研究项目“焊接材料强度失配和热影响区软化行为研究”
国家重点研发计划“高钢级管线钢低温强韧化控制的冶金学原理及关键技术”(项目编号2017YFB0304901)。
关键词
X80管道
环焊接头
微观组织
力学性能
热输入量
析出物
X80 pipeline
girth welding joint
microstructure
mechanical properties
heat input
precipitates
