摘要
测试了各种焊接工艺参数对SA335P91炉管全位置打底焊左右焊道交汇时小孔闭合处的热循环曲线的影响。分析结果表明,电弧在闭合小孔处停留时间thole对小孔闭合处的焊接热循环曲线主参数峰值温度Tmax和高温停留时间Δt800的影响最为显著,其次是焊接电流I,再其次是焊接速度v,而预热温度T0 的影响不明显。过长的thole和过大的焊接电流I都会导致该处结晶组织粗大,方向性强是产生结晶裂纹的主要原因。
The paper has tested the effect of the various welding parameters on the thermal cycle curves of the points where the hole is sealed when the left and right beads are connected in condition of all position backing welding of SA335 P91 boiler tube.The results show that, the influence of the parameter t hole on the peak temperature T max and the keeping time at high temperature Δt 800 is most marked, the secondary is I , the third is v , while T 0 is the weakest. The supper long timet hole and the supper big welding current I will cause coarse crystal structure with intensive directivity and that is main reason causing crystal crack.
出处
《焊接》
北大核心
2005年第4期15-19,共5页
Welding & Joining
