小口径不锈钢圆管自动TIG焊接工艺参数  

Automatic TIG welding parameters of small diameter stainless steel pipes

作　　者：刘刚 张梦金 何之 薛龙[2] 黄军芬[2] Liu Gang;Zhang Mengjin;He Zhi;Xue Long;Huang Junfen(China Nuclear Power Technology Research Institute Co.,Ltd.,Shenzhen 518000,Guangdong,China;Beijing Institute of Petrochemical Technology,Beijing 102617,China)

机构地区：[1]中广核研究院有限公司,广东深圳518000 [2]北京石油化工学院,北京102617

出　　处：《焊接》2024年第5期16-20,29,共6页Welding & Joining

基　　金：国家重点研发计划项目(2022YFB4701100)。

摘　　要：壁厚大于3 mm的小口径不锈钢圆管I形坡口自熔焊接,易出现未焊透缺陷,严重影响焊接质量。针对外径ϕ32.5 mm、壁厚为3.25 mm的304奥氏体不锈钢圆管I形坡口,采用自动钨极氩弧焊自熔焊接方法,通过数值模拟和焊接试验研究焊接工艺参数中焊接电流和起弧预热时间对焊缝成形的影响。由数值模拟得出焊接电流、起弧预热时间与焊缝成形参数的对应关系,初步确定圆管自熔焊接试验的焊接电流和起弧预热时间范围。然后,通过自动钨极氩弧焊自熔焊接试验,得出了焊缝成形良好时的具体焊接电流、起弧预热时间。试验结果表明,焊接速度为100 mm/min、焊接电流为105 A,115 A时,圆管环缝中间焊段能够实现熔透,且焊缝不会产生塌陷缺陷。焊接电流为115 A、起弧预热时间为4 s和5 s时,起弧段焊缝背面熔宽较为稳定,能够确保焊缝可靠熔透。Self-fusion welding for I-groove of small diameter stainless steel pipes with wall thickness greater than 3 mm is prone to incomplete penetration defects,which seriously affects their welding quality.Automatic self-fusion tungsten inert gas(TIG)welding method was adopted for I-groove of 304 austenitic stainless steel pipes with outer diameter ofϕ32.5 mm and wall thickness of 3.25 mm,and influence of welding current and initial arc preheating time of welding parameters on formation of weld was studied through numerical simulation and welding tests.The corresponding relationships between welding current,initial arc preheating time and forming parameters of weld were obtained by numerical simulation,and the preliminary ranges of welding current and initial arc preheating time for self-fusion welding tests of pipes were determined.Then,the specific welding current and initial arc preheating time for good formation of weld were obtained through automatic TIG welding tests.The test results showed that when welding speed was 100 mm/min and welding current was 105 A or 115 A,the middle section of circumferential weld of pipes could achieve penetration,and the weld would not produce excessive penetration.When welding current was 115 A and initial arc preheating time was 4 s or 5 s,weld width at the back of initial welding section was relatively stable,which could ensure reliable penetration of weld.

关 键 词：自动钨极氩弧焊 自熔焊接 焊缝成形 焊接过程数值模拟 

分 类 号：TG444[金属学及工艺—焊接]