JPH0454545B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of welding pipes together.

(Prior art) Conventionally, arc (TIG) welding is generally used to weld pipes together, and as shown in Fig. 3, filler metal (wire) is applied to the welded parts of both pipes A and B.
While applying C, welding machine D was manually operated and the position was gradually changed to weld the entire circumference of the pipe.

(Problems to be Solved by the Invention) However, the TIG welding requires great skill and a large number of man-hours, and is also a cause of increased costs.

As a countermeasure for this, automated welding machines have been developed in recent years, but they are equipped with a wire (filler metal) supply device that rotates the torch, and this wire supply device depends on the shape of the pipe to be welded. In the past, interference occurred and automation was impossible. Therefore, I removed the wire and tried welding it, but it was impossible to weld it.

Therefore, the present invention provides a welding method that allows pipes to be welded without using wires.

(Means for Solving Problems) The gist of the present invention is to perform bead processing to form a protrusion 3 near the end of one pipe 1 at a position slightly set back from the end, and to form a protrusion 3 on the other pipe 2. , a receiving part 4 is formed whose open end is expanded to the same extent as the external dimensions of the one pipe 1,
The above-mentioned one pipe 1 is inserted into the receiving part 4 of the other pipe 2, and the projecting part 3 of one pipe 1 and the vicinity of the receiving part 4 of the other pipe 2 are heated and melted and welded.

(Function) Therefore, the protruding part formed on one pipe and the receiving part of the other pipe can be melted and both pipes can be welded together, thus making wireless welding possible. It is something.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In Fig. 1, pipe 1 and pipe 2 are manufactured using the same aluminum as the main raw material in this example, and pipe 1 has an outwardly protruding portion 3 formed by bead processing at a position slightly set back from its end. has been done.

The open end of the pipe 2 is expanded to the same extent as the external dimensions of the pipe 1, and a receiving portion 4 is formed.

When both pipes 1 and 2 have been processed in this way, the tip of pipe 1 is inserted into the receiving part 4 of pipe 2, and then the vicinity of the protruding part 3 and receiving part 4 of the pipe 1 is welded using the arc welder 5. Heat and melt the entire circumference. As a result, the top of the protrusion 3 is melted, and as shown in FIG. 2, the welded part 6 is welded with a uniform thickness (approximately twice the thickness of the pipes 1 and 2). For this reason, surface roughness does not occur in the pipes 1 and 2 (excluding the welded parts) due to welding. In addition, the welded part 6 is 2 times the wall thickness of the pipe.
It is about twice as thick and has R parts (shown in Figure 2) on both sides, making it the same thickness as a normal pipe, so stress concentration on the welded parts can be avoided and the strength can be improved. It also prevents the inner surface from swelling up during welding due to the wall thickness.

(Effects of the Invention) As described above, according to the present invention, welding can be performed without wire supply, and even if the pipe has a complicated shape, it does not have a wire supply device, so it is possible to weld the pipe without wire supply. Recruitment became possible. Since the protrusion formed on one side of the pipe is formed by bead processing, even a relatively thin pipe can be doubled in thickness, ensuring enough melting for the top of the protrusion. The welded part is approximately twice the thickness of the pipe wall, and both ends are rounded, which prevents stress from concentrating on both ends of the welded part.
The strength is significantly improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of welding according to the present invention, and FIG. 2 is a half-sectional view showing a welding state according to the present invention.
FIG. 3 is a half-sectional view showing a conventional example in which welding is performed while supplying wire. 1...One pipe, 2...The other pipe, 3
...Protruding part, 4...Receiving part, 5...Welding machine.

Claims (1)

[Claims] 1. A bead is formed near the end of one pipe 1 to form a protrusion 3 at a position slightly set back from that end, and the other pipe 2 has an open end that has the same external dimensions as the one pipe 1. A receiving part 4 is formed which is expanded to a certain extent, and the one pipe 1 is inserted into the receiving part 4 of the other pipe 2, and the protruding part 3 of one pipe 1 and the vicinity of the receiving part 4 of the other pipe 2 are formed. A pipe-to-pipe welding method characterized by heating, melting, and welding.