Φ219mm以下油气管道焊接施工长期以来采用手工焊,施工效率低、成本高。由于小管曲率大,传统半自动焊的连续性作业和焊速较高的特点,使得焊接操控难度大,焊口合格率低。本文针对小口径管道新型半自动下向焊技术及材料,结合焊工培训对小口径管道半自动下向焊施工做出论证。 Φ219mm the following oil and gas pipeline welding has long been using manual welding, construction of low efficiency and high cost. Due to the small tube curvature, the traditional semi-automatic welding of the continuous operation and welding speed characteristics, making the welding control difficult, welding pass rate is low. In this paper, a new type of small-diameter pipe welding technology and materials of semi-automatic, combined with welder training of small-diameter pipe to make a demonstration of the semi-automatic downwards welding.