碱性渣系气体保护药芯焊丝立向上焊接工艺

采用平板对接立向上焊接、焊接电弧物理观察等试验方法，观察了碱性渣系气体保护药芯焊丝熔滴过渡和电弧特性，研究了立向上焊焊缝成形机理及影响因素。结果表明，碱性焊丝立向上焊时，粗熔滴非轴向过渡和集中、活动型电弧特性使熔滴过渡的定向性很差，熔滴飞溅增大；碱性熔渣的流动性大，凝固速度慢，对熔池的扶托作用差，熔池的形状较难控制，焊缝成形相对困难。采用合理的、最佳匹配的焊接参数和有效的操作技术和运丝方式是获得满意立向上焊缝的必要条件。

VERTICAL -UP WELDING PROCEDURE FOR GAS SHIELDED FLUX CORED WIRE OF BASIC SLAG SYSTEM

A series of methods including plane butting vertical-up welding, welding arc physical observation, etc. were applied to observe the droplet transfer and arc properties of the gas shielded flux cored wire of basic slag system, and the paper studied the shaping mechanism and influencing factors of the vertical-up welding. The results showed that in vertical-up welding of basic flux cored wire, because of the non-axial transfer of the coarse droplet and the convergent and active arc, the directionality of droplet transfer is bad and the droplet spatter increases, and owning to the better fluidity and slower solidification velocity of basic slag, its supporting action on the molten pool is not good so that the shape of molten pool is difficult to control and the shaping of weld becomes difficult. The necessary condition to obtain satisfied vertical-up weld is adopting optimal welding parameters,efficient operating technique and reasonable wire feed mode.