厚板窄间隙多道埋弧焊温度和残余应力分布

TEMPERATURE DISTRIBUTION AND RESIDUAL STRESS IN MULTI-PASS NARROW GAP SUBMERGED ARC WELDING

通过有限元数值模拟的方法,分析厚板窄间隙埋弧焊的温度分布,同时给出了厚板上、下表面和厚度方向上的残余应力分布曲线。通过热电偶构成的温度测量系统测得试板特定点上的温度分布,且在焊接完成冷却一段时间后利用盲孔法测量了试板上、下表面特定点上残余应力大小。有限元计算结果和试验测量结果吻合较好,证明了该有限元模型的合理性,为评价焊接接头性能提供了参考。特别是,在厚度方向上不便测量的残余应力分布曲线可以通过有限元数值模拟的方法获得,为实际考查厚板内部残余应力分布提供依据。对于两者结果有较大偏差的地方,分析该偏差出现的原因。

By the methods of finite element analysis （FEA）, the temperature distribution of thick plate narrow gap submerged arc welding （SAW） is analyzed. Also the residual stress distribution of upper surface, lower surface and along the thick direction is presented. The temperature distribution of specific points is measured by the temperature measurement system of thermocouple. After welding and cooling for a long time, the residual stress of the specific points of the upper and lower surface of the plate. The testing results are coincided with those of FEA which proves the rationality of this finite element model and offers reference to appraise the weld performance. In particular, the residual stress distributing curve in the thick direction which is inconvenient to measure is gained by FEA. There is large deviation between these two results in the base metal zone and the reason of this deviation is presented.