The etched section also reveals that multiple weld passes were made over the top of the original submerged arc weldpass.
从酸蚀断面还可以看出：在原自动埋弧焊的上面覆盖有多层焊道。
2
The effects of tempering weld-pass treatment on toughness of HAZ of X80 pipeline steel were studied by the technique of welding thermal simulation and the method of microscope analysis.
采用焊接热模拟技术和显微分析方法，研究了回火焊道热处理对X80级管线钢焊接热影响区韧性的影响规律。
3
Regarding to submerged arc weld multi-passweld track and height of weld gun, two-dimension track system is designed.