高速三丝熔化极气保护焊接工艺

Three-wire MAG high speed welding process

针对造船企业平面分段生产流水线纵骨双丝角焊接最大焊接速度小于1.0m/min的问题,研究开发了高速三丝熔化极气保护焊接新工艺,即三根焊丝分别为引导焊丝、中间焊丝和跟随焊丝纵向排列。每根焊丝各接一套送丝系统、焊接电源和保护气,构成独立的电弧-电源系统,其焊接工艺参数分别可调,以满足各种焊接要求。结果表明,当采取引导焊丝(DCEP)/中间焊丝(DCEN)/跟随焊丝(DCEP)或引导焊丝(DCEN)/中间焊丝(DCEP)/跟随焊丝(DCEN)的极性组合时,焊接过程稳定,焊缝外观表面光洁、左右对称、起渣容易、飞溅小、无气孔,满足船舶焊接的要求。通过选用合适的焊接电流、电压组合,可以使焊接速度达到1.8m/min,焊脚长度达5～8mm。此焊接新工艺可广泛用于角焊缝的高速焊接应用场合。

A new technology of three-wire MAG high speed welding is researched to replace two-wire welding technology which is usually used to weld fillet in shipyard and the welding speed is under 1.0 m/min. Three wires, namely, leading wire, middle wire and trailing wire, are arranged in tandem. Each wire is equipped with separate wire feeder system, power supply and gas shield device, and welding process parameters can be adjusted individually to meet the various requirements of welding. The results show that the polarity combination of leading wire (DCEP)/middle wire (DCEN)/trailing wire (DCEP) or that of leading wire (DCEN)/middle wire (DCEP)/ trailing wire (DCEN) can obtain stable welding process, good weld appearance, symmetrical weld seam, non-porous weld to meet the requirements of the shipbuilding industry; the maximum welding speed can be up to 1.8 m/min and the length of fillet weld leg can be to 5-8 mm by selecting a suitable welding current and welding speed. This new welding technology can be widely used for highspeed fillet welding industry.