Full penetration welding method for U ribs

The invention provides a full penetration welding method for U ribs. According to the method, a reverse dip angle is arranged on a to-be-welded panel relative to the horizontal plane during backing welding, a poly-arc pulse deep penetration welding gun at a specific angle is matched to carry out welding, and through gravity, a phenomena of embossment and undercut caused by tensile force on the surface of molten iron can be overcome, so that full penetration welding between U ribs and panel welding seams is well completed, and the forming at the inner side and outer side is favorable. Through full penetration welding seams, net sectional areas of the welding seams are ensured, so that equal strength between the welding seams and base materials is ensured, the phenomenon of stress concentration of welding seam roots due to partial penetration is avoided and the anti-fatigue performance of welding joints is effectively enhanced. 本发明提供了种U肋全熔透焊接方法。通过在打底焊中，将待焊接的面板相对水平面设置个反向倾角，配合特定角度的聚弧脉冲深熔焊枪进行焊接，通过重力可以克服铁水表面张力引起的凸起