A saddle-type large tube seat welding method

Abstract

The invention discloses a welding method of a saddle-type large pipe seat, which comprises the following steps: A) marking the center line of the pipe hole of the pipe seat on the cylinder body, and marking the abdominal surfacing welding filling range line on the cylinder body according to the size of the pipe seat; B) Surfacing metal on the abdomen of the cylinder body to be higher than the shoulder according to the surfacing welding filling range line of the abdomen, and the outer edge of the surfacing metal is larger than the outer diameter of the pipe seat; The center line of the hole is the normal line, and the top of the surfacing metal is processed into a plane, which is perpendicular to the center line of the pipe hole, and its height is higher than the shoulder; D) Process the end of the pipe seat connected to the cylinder with a bevel; E) Assemble the pipe seat and the cylinder and weld the butt weld of the pipe seat and the cylinder; the invention can reduce the difficulty of welding and groove processing of the fillet weld of the pipe seat, improve the stability and reliability of welding quality, and facilitate Realize the automation and intelligence of pipe seat fillet weld welding, reduce welding labor intensity and improve the working environment.

Description

technical field [0001] The invention relates to a pipe seat welding method, in particular to a saddle-type large pipe seat welding method used for a power station boiler header. Background technique [0002] The header is an important pressure-bearing part of the power plant boiler, such as figure 1 As shown, there are many pipe sockets 7 with a diameter of φ100mm~φ355.6mm and a wall thickness of 10~75mm arranged on the cylinder 6. The groove is a saddle-shaped groove, so this type of connecting pipe seat is usually called a saddle-type large pipe seat. The welding feature is that the outer diameter of the header cylinder 6 is smaller than the outer diameter of the pipe seat 7. Seam 8 (the place with the smallest weld filling) and abdominal weld 9 (the place with the largest weld filling) are very different in cross section, and the positions of the two welds differ by 90 degrees in the circumferential direction, and the welding filling is extremely uneven; The wall thickn...

AI Technical Summary

Problems solved by technology

[0002] The header is an important pressure-bearing part of the power plant boiler, such as figure 1 As shown, there are many pipe sockets 7 with a diameter of φ100mm~φ355.6mm and a wall thickness of 10~75mm arranged on the cylinder 6. The groove is a saddle-shaped groove, so this type of connecting pipe seat is usually called a saddle-type large pipe seat. The welding feature is that the outer diameter of the header cylinder 6 is smaller than the outer diameter of the pipe seat 7. Seam 8 (the place with the smallest weld filling) and abdominal weld 9 (the place with the largest weld filling) are very different in cross section, and the positions of the two welds differ by 90 degrees in the circumferential direction, and the welding filling is extremely uneven; The wall thickness is very thick, the welding filling volume is large, the welding bead is many, and the welding bead layout is difficult; the horizontal welding position is welded, the saddle drop is large, the weld shape control requirements are high, and the welding is very difficult; therefore, for this type of pipe seat Usually, "manual argon tungsten arc welding decoration, backing + manual arc welding filling and covering" or "manual argon tungsten arc welding decoration, backing + manual arc welding transition + gas shielded welding filling and covering" are manually or The semi-automatic welding operation method not only has low automation, high labor intensity, and poor welding environment, but also the quality of welding depends entirely on the welder's operating level and sense of responsibility

Images