摘要
为探究送进式焊剂片约束电弧超窄间隙焊接的工艺参数匹配,自主设计制作了一套送进式焊剂片约束电弧超窄间隙焊接装置,以提高焊接过程稳定性和自动化水平。利用瞬间中断电弧的方法保留了熄弧位置处焊缝形态和焊剂片末端熔化形貌,发现焊接电压和焊剂带送进速度都是通过改变焊剂片对电弧的作用长度来影响焊缝成形,焊剂片对电弧的作用长度可表现为焊剂片对电弧固壁约束面积。通过改变焊剂带送进速度和焊接电压进行了试验研究,结果表明,当焊剂片对电弧固壁约束面积适中时,电弧集中加热区域会下移至间隙底部和侧壁根部,获得根部熔合良好的焊缝;当焊剂片对电弧固壁约束面积较大时,电弧受约束程度过强,电弧加热区域集中在间隙底部,分布于侧壁根部电弧热量很少,焊道上部会有熔池堆积;当焊剂片对电弧固壁约束面积较小时,电弧受约束程度较弱,会沿侧壁攀升导致加热区域集中在两侧壁上,很难在坡口根部形成有效熔池,最终形成孔洞焊缝。确定了最佳的焊接电压范围为21.5~24.5 V,焊剂带送进速度2.1~2.6 mm/s,利用该参数进行超窄间隙单道多层焊接可以获得成形良好的焊缝。
Welding with flux sheet confined arc ultra-narrow gap welding A new ultra-narrow gap welding method using flux sheet to constrain arc with 4~6 mm I groove.The matching between welding process parameters will affect weld formation.We independently designed and produced a set of ultra-narrow gap welding device for confined arc with flux sheet,which improved the stability and automation of welding process.The weld shape at the arc quenching position and the melting morphology at the end of flux sheet were preserved by the method of instantaneous arc interruption.It was found that both welding voltage and flux belt feeding speed affected weld formation by changing the length of flux sheet on arc,and the length of flux sheet on arc can be expressed as the confined area of flux sheet on arc wall.The results show that when the confinement area of flux sheet on arc wall is moderate,the arc centralized heating area will move down to the bottom of the gap and the root of the side wall,and a good fusion of the root is obtained.When the confined area of flux sheet on arc wall is large,the constrained degree of arc is too strong,the arc heating area is concentrated at the bottom of the gap,the arc heat distributed at the root of the side wall is little,and there will be molten pool accumulation on the weld path.When the constraint area of the flux sheet on the arc wall is small,the constraint degree of the arc climbing along the side wall is weak,resulting in the heating area concentrated on both sides of the wall,and it is difficult to form an effective molten pool at the root of the groove, and finally form a hole weld. Finally, a series of process parameter matching tests were carried out to obtainthe optimal process parameter matching range of the ultra-narrow gap welding confined by the flux sheet, and the optimalprocess parameters were used to carry out the ultra-narrow gap single-pass multi-layer welding tests.
作者
郭宁
朱亮
张爱华
周辉
刘振民
孙鹏
GUO Ning;ZHU Liang;ZHANG Aihua;ZHOU Hui;LIU Zhenmin;SUN Peng(Lanzhou University of Technology,State Key Lab.of Advanced Processing and Recycling of Non-Ferrous Metals,Lanzhou 730050,China;Lanzhou University of Technology,School of Electrical Engineering and Information Engineering,Lanzhou 730050,China)
出处
《电焊机》
2024年第3期60-66,共7页
Electric Welding Machine
基金
国家自然科学基金(621731170)。
