Tube plate dovetail welding seam one-time forming welding method and tube plate dovetail structure

The invention discloses a tube plate dovetail welding seam one-time forming welding method and a tube plate dovetail structure in order to rapidly conduct tube plate dovetail welding seam welding, reduce stress concentration and reduce the probability of dovetail welding seam defect generation, and the tube plate dovetail welding seam one-time forming welding method and the tube plate dovetail structure are characterized in that base plates extending out are arranged at the two ends of a cover plate of the dovetail structure. Forming a back backing weld joint; back gouging is conducted on the back backing weld joint of the dovetail structure; backing welding is conducted on the front face of the dovetail structure, and a front face backing welding seam is formed; the back backing weld after back gouging is filled with a capping weld; and a capping weld is filled on the front backing weld. According to the method, manual digging and cleaning and repeated welding operation of the front welding seam end of the d