X65级海管环缝无衬垫封底全自动焊工艺及焊缝性能研究  

Without Backing Auto-GMAW Welding Process Decelopment and Mechanical Test for X65 Pipeline Girth Weld

作　　者：刘岩磊 孙有辉[1] 刘永贞[1] 韩永典[2] 李子轩 LIU Yanlei;SUN Youhui;LIU Yongzhen;HAN Yongdian;LI Zixuan(Offshore Oil Engineering Co.,Ltd.,Tianjin 300452,China;Tianjin Universicy,Tianjin 300354,China)

机构地区：[1]海洋石油工程股份有限公司,天津300452 [2]天津大学,天津300354

出　　处：《电焊机》2023年第11期23-27,34,共6页Electric Welding Machine

摘　　要：在一些国外海洋油气田开发项目中,输送含有酸性腐蚀介质的海底管道环缝焊接强制要求采用无铜衬垫封底焊接技术,确保焊缝在硫化氢(Hydrogen Sulfide,H2S)酸性腐蚀服役过程中不会出现硫致应力开裂(Sulfide Stress crack,SSC)。为解决铜衬垫在封底焊接过程中铜原子受热扩散进入焊缝金属并对其性能产生破坏性影响的问题,采用表面张力过渡(Surface Tension Transfer,STT)封底焊接和熔化极气体保护焊接(Gas Metal Arc Weld‐ing,GMAW)填充盖面焊接技术,开发了一种适用于海管S型铺设的无衬垫封底全自动焊工艺并对焊缝性能进行测试研究。结果表明,横向拉伸、全焊缝拉伸、侧弯、冲击、宏观硬度及H2S腐蚀试验等均满足项目焊接规格书及DNV OS F101(2013)标准要求;焊接接头试样均通过了NACE 0177标准下的硫致应力开裂试验,可应用于含H2S酸性环境下X65级碳钢海管的焊接施工。STT表面张力过渡封底焊接属于单面焊双面成形技术,焊接热输入小,飞溅极少,焊缝成形好,是无衬垫封底焊接技术的一种可靠选择。In some overseas offshore oil and gas field development projects,the girth welds of submarine pipelines sub‐jected to sour servive condition is mandatory to use welding process for root pass without copper shoes to ensure that the welds will not have sulfide stress crack(SSC)during the service process of hydrogen sulfide(H2S)acid corrosion.In order to solve the problem that copper atoms of copper shoes are diffused into the weld metal and have a destructive effect on its performance during the root pass welding,a full-automatic GMAW welding process without backing for pipeline S-lay and mechanical tests were developed by using surface tension transfer(STT)for root pass and gas metal arc welding(GMAW)for fill and cap passes.The test results of mechanical properties meet the requirments of the project welding specification and DNV OS F101(2013)standard.All welded joint samples have passed the sulfur-induced stress cracking test under NACE 0177 standard,and can be applied to the welding construction of X65 carbon steel subsea pipe in acidic environment containing H2S;STT surface tension transfer for root pass welding is a single-sided welding and double-sided forming tech‐nology,with small welding heat input,little spatter,and good weld formation.It is a reliable choice for backing less back cover welding technology.

关 键 词：X65海管 无衬垫全自动焊接 表面张力过渡 硫致应力开裂 

分 类 号：TG457.6[金属学及工艺—焊接]