熔嘴电渣焊在莱钢高炉炉壳立缝焊接中的应用

Application of Electro Slag Welding with Consumable Nozzle in the Vertical Welding of Blast Furnace Shell in Laigang

针对高炉炉壳立缝需要在垂直位置焊接及钢板厚度大的特点,为保证焊接质量,采用了熔嘴电渣焊焊接工艺。利用电流通过液体熔渣所产生的电阻热,将送入渣池的焊丝与导丝管熔化,作为填充金属,通过水冷滑块强制焊缝成形。同时,适当增大金属熔池的形状系数、减小焊缝晶粒结晶时的交会角,以减少焊缝偏析、降低热裂纹敏感性。检测表明,焊缝外观质量良好,射线探伤合格率100%,焊缝力学性能满足要求,高炉已经顺利达产。

Pointing to characteristics that the erect joint of the furnace shell should be welded vertically and the steel plate is thick, the process of electro slag welding with consumable nozzle is adopted to ensure welding quality. The resistance heat that the current produces through the liquid slag makes the electrode wire and the wire guide melting as filler metal,and the metal is forced by water-cooled slide shoes to solidify welding joint. At the same time, in order to reduce the segregation of the welding seam and play down the thermal crack susceptibility, the shape coefficient of the puddle is augmented properly and the angle of the crystal grain in crystallizing is minished. Examines show that the appearance of welding joint is excellent, the percent of pass in X-ray test is 100% and the mechanical properties meet the needs of process. Now the BF has reached full designed productivity.