X80管线钢低氢焊条根焊技术

目前我国大直径长输管道大部分采用X80管线钢，X80钢根焊道的焊接常采用管道全位置自动焊、STT和RMD半自动焊、钨极氩弧焊以及焊条电弧焊等工艺。管道全位置自动焊设备昂贵、适应性差。STT和RMD半自动焊焊接时灵活性较差，必须严格防风措施。钨极氩弧焊的抗风能力差且焊接效率太低。低氢焊条电弧焊虽操作难度大且焊接效率不高，但灵活性强、焊接接头力学性能好且设备简单，适应于返修、连头和不良地段的焊接。详细介绍了X80管线钢低氢焊条根焊焊道的焊前准备、焊接操作技术及焊接工艺参数。

Low-hydrogen Electrode Root Welding Technology of X80 Pipeline Steel

At present, X80 pipeline steel mostly was used in large diameter long-distance pipeline in China. In X80 steel root welding, it usually adopts all position automatic welding, STT and RMD semi-automatic welding, tungsten argon arc welding, shielded metal arc welding, etc. The equipment of pipeline all position automatic welding is expensive, poor adaptability; windproof measures must be strictly controlled in STT and RMD semi-automatic welding; The poor ability to resist the wind for tungsten argon arc welding and its welding efficiency is too low. Although high operation difficulty and low welding efficiency for low hydrogen electrode arc welding, but it is with good flexibility and simple equipment, the mechanical properties of welded joint are good, suitable for welding repair, butt welding and welding in bad location. In this article, it detailedly introduced preparation before welding, welding technology and welding parameters for X80 pipeline steel low-hydrogen electrode root welding bead.