潜弧焊技术在侧墙板拼接焊缝上的应用

Application of submerged arc welding process in splice weld of side walls

针对粮食漏斗车、煤炭漏斗车侧墙采用板材拼接结构,须采取双面焊接,存在清根、补焊及修型耗费辅助工时、人力成本高、打磨清根粉尘污染大的问题,通过采用熔化极气体保护焊单面焊双面成形技术,自主研制拼板自动焊接专机。以脉冲气体保护焊工艺,辅加背侧强制成型冷却系统,并通过优化焊接工艺参数,成功实现了侧板对接焊缝的潜弧焊焊接。在附加脉冲特性下的焊缝余高值显著降低,与母材平滑过渡,机械性能及金相组织优良。在产品批量生产应用过程中,结合铁路货车产品的侧墙结构特点,控制了焊缝成形效果,降低了焊缝余高,减少了侧板焊接变形,有效控制货车运行风阻、风噪,令产品外观商业化满足客户要求。

In view of the splicing structure of the panels for side walls of grain and coal hopper cars,double-sided welding must be adopted,which inevitably brings about problems involving extra working hours,high labor cost and heavy pollution for back gouging,repair welding and redressing operation,The submerged arc welding of the side panel butt weld is successfully achieved by using pulsed gas shielded welding process,supplemented by a forced forming cooling system on the back side,and optimizing the welding process parameters.Under the additional pulse characteristics,the weld reinforcement value significantly decreases and smoothly transitions to the base metal with excellent mechanical properties and microstructure.In the process of mass production and application of the products with the structural characteristics of the side walls of railway freight cars,the welding seam forming effect is controlled,the weld reinforcement is reduced,the welding deformation of the side wall is reduced,and the wind drag and noise during the freight car operation are effectively controlled,enabling the product appearance to meet customers'requirements.