30mm厚EH420船板钢三丝埋弧焊接温度场数值模拟研究

Numerical simulation on temperature field of three wire submerged arc welding of 30 mm EH420 ship plate steel

为了减少焊接时产生的高温对热影响区韧性的影响,分别研究了焊接线能量、焊丝功率分配、焊接电压和焊丝间隔对温度场的影响。基于Visual-Environment有限元软件,利用双椭球热源模型,对30 mm厚EH420船板钢三丝埋弧焊接温度场进行了数值模拟。结果表明:1)当线能量从150.26 kJ/cm降低到104.72 kJ/cm时,粗晶区峰值温度降低了322℃;2)当线能量相同时,前丝功率占比从25.00%上升到41.67%,且中丝功率占比不变的情况下,粗晶区峰值温度降低了56.79℃;3)提高焊接电压后,粗晶区峰值温度、熔深和熔宽变化较小;4)焊丝间隔从20 mm增加到45 mm,熔池长度增大了50 mm,并在焊丝间隔40 mm之后出现由单熔池向双熔池转变的现象,粗晶区峰值温度呈现先增大后减小的趋势,焊丝间隔在35 mm达到最高温度1183.62℃;5)从拟合结果得出,在焊接30 mm厚的EH420船板钢“Y”型坡口时,线能量应采用174.54 kJ/cm,在此线能量下前、中、后丝的功率占比采用15∶11∶7且焊丝间隔为20~30 mm,能够有效避免出现焊接缺陷。研究结果既可以保证焊接质量,又可以大幅提高焊接效率,为企业降本增效提供新方法。

In order to minimize the effect of the high temperatures generated during welding on the toughness of the heat-affected zone,the effects of welding line energy,wire power distribution,welding voltage and wire spacing on the temperature field were investigated separately.Based on Visual-Environment finite-element software,numerical simulation of the temperature field of three wire submerged arc welding of 30 mm EH420 shipboard steel was carried out by utilizing the double-ellipsoid heat source model.The results show that:1)When the welding energy definition decreases from 150.26 kJ/cm to 104.72 kJ/cm,the peak temperature in the coarse crystal area decreases by 322°C.2)At the same welding energy definition,the peak temperature in the coarse crystal area decreases by 56.79℃when the power share of the first welding wire increases from 25.00%to 41.67%and the power share of the middle welding wire remains unchanged.3)Increasing the welding voltage results in less variation in peak temperature,depth and width in the coarse crystal area.4)The wire spacing increases from 20 to 45 mm,the length of the melt pool increases by 50 mm,and there is a transition from single melt pool to double melt pool after the wire spacing of 40 mm.The peak temperature of the coarse crystal area shows the trend of increasing and then decreasing,and the wire spacing of 35 mm reaches a maximum temperature of 1183.62℃.5)From the fitting results,in welding 30 mm EH420 ship plate steel"Y"type interface,the welding energy should be 174.54 kJ/cm.In this welding energy the power ratio of the front,middle and rear wires should be 15∶11∶7,and the wire spacing should be 20~30 mm,which can effectively avoid the welding defects.The research results can not only ensure the welding quality,but also significantly improve the welding efficiency,providing a new method for the enterprise to reduce costs and increase efficiency.