JP3767198B2 - TIG welding torch for horizontal welding - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a TIG welding torch for lateral welding suitable for lateral welding of a narrow groove.
[0002]
[Prior art]
In recent years, TIG welding torches used for groove welding by butting members such as plate materials have been developed with electrodes having a multi-electrode structure so that high-speed welding can be performed while allowing a large current to flow. ing.
[0003]
Among the TIG welding torches having the above-mentioned multi-electrode structure, those developed for transverse welding with a narrow groove are elongated flat plates arranged side by side as shown in FIGS. 3 (a), (b) and (c). A flat groove 2 is provided along the longitudinal direction on the upper side surface and lower side surface of the insulating plate 1, and an upper electrode 3 and a lower electrode made of tungsten and connected to different power sources in the flat groove 2. 4 is inserted, the insulating plate 1 is held by the upper electrode 3 and the lower electrode 4, and the rear side with respect to the welding direction (arrow X direction) of the insulating plate 1 and the insulation arranged in contact with the rear side An electrode structure 6 having a flat cross-sectional shape configured to pass the welding wire 5 through the boundary with the body wire guide 1a is configured, and the electrode structure 6 is supported by the torch body 8 and the electrode structure Shield gas 7 is ejected from the tip of 6 That is a structure in which so as to required length protruding from the distal end of the gas cup 9.
[0004]
[Problems to be solved by the invention]
However, when the narrow groove 11 formed between the thick plates 12 is welded sideways using the TIG welding torch shown in FIGS. 3 (a), (b), and (c), gravity acts on the molten metal 10, In the case of one layer and one pass, an overlap portion 13 is generated on the lower wall 11a side of the narrow groove 11, which causes poor penetration on the lower wall 11a side of the narrow groove 11 and hinders welding accuracy. This raises problems.
[0005]
Incidentally, in the conventional TIG welding torch having a single electrode structure, multilayer distribution welding is performed in order to prevent the occurrence of an overlap portion. However, in a multi-electrode TIG welding torch, since the electrode structure is large, As in the case of the electrode, the sorting cannot be performed, and the sorting welding has a problem in terms of efficiency.
[0006]
In view of the above, the present invention is intended to prevent a weld metal accuracy from being hindered by preventing an overlap portion of molten metal from occurring on the lower wall side of a narrow groove.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a TIG welding for lateral welding having an electrode structure in which an elongated flat plate-like insulating plate is sandwiched from above and below by a strip-like upper electrode and a lower electrode. in the torch, the cathode spot of the cathode spot and the lower electrode of the strip-shaped upper electrode, the cathode spot of the upper electrode in a state arranged in parallel with the welding direction transverse KyoHiraki destination upper and lower electrodes is lower It is set as the structure set so that it may be located in the back of a welding direction rather than the cathode spot of an electrode .
[0008]
When the narrow groove is welded sideways, the molten pool is formed so as to incline backward with respect to the welding direction, so that an overlap portion of the molten metal is formed on the lower wall side of the narrow groove due to drooping from above. Before, the lower wall side of the narrow groove can be sufficiently melted by the arc of the lower electrode. Therefore, the welding accuracy can be increased.
[0009]
Also, the tip of the upper electrode is cut obliquely rearward toward the tip so that the most advanced cathode spot is located on the rear side of the welding direction, and the tip of the lower electrode is cut in the welding direction. If the structure is cut obliquely forward toward the tip so as to be located on the front side of the metal, the inclination angle of the molten pool can be increased, so that the degree of dripping of the molten metal can be greatly reduced. .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0011]
1 (a), (b), and (c) show an embodiment of the present invention, and as shown in FIGS. 3 (a), (b), and (c), an elongated flat plate-like insulating plate arranged sideways. 1 in a TIG welding torch for transverse welding having an electrode structure 6 having a flat cross-sectional shape that is sandwiched from upper and lower sides by a strip-like upper electrode 3 and lower electrode 4, the welding direction of the laterally narrow groove 11 (arrow) X direction), the tip of the upper electrode 3 is cut obliquely backward, and the tip of the lower electrode 4 is cut obliquely forward, so that the leading edges of the upper electrode 3 and the lower electrode 4 are cut. The cathode spots 3a and 4a are set so that the cathode spot 3a of the upper electrode 3 is relatively located on the rear side. The rest of the configuration is the same as that shown in FIGS.
[0012]
Using the TIG welding torch for lateral welding according to the present invention having the above-described configuration, when the lateral narrow gap 11 formed between the thick plates 12 is welded laterally in one layer and one pass, the cathode spot 3a of the upper electrode 3 is Since the cathode spot 4a of the lower electrode 4 is positioned on the front side on the rear side, the arc is deflected back and forth, so that the molten pool 10a is formed to tilt backward with an inclination angle θ. Therefore, before the overlap portion is formed on the lower wall 11a side of the narrow groove 11 due to the molten metal 10 hanging down from the upper side, the lower wall 11a side of the narrow groove 11 is sufficiently formed by the arc of the lower electrode 4. Can be dissolved in. Further, since the molten pool 10a is inclined backward, the degree of dripping of the molten metal 10 can be greatly reduced. Therefore, the welding accuracy can be increased.
[0013]
Next, FIGS. 2 (a) and 2 (b) show other embodiments of the present invention, and the horizontal welding TIG has the same configuration as shown in FIGS. 3 (a), (b) and (c). In the welding torch, FIG. 2 (a) shows a case where the tip of the upper electrode 3 is cut obliquely rearward and the tip of the lower electrode 4 is center-cut in a mountain shape, and FIG. ) Shows a case where the tip of the upper electrode 3 is center-cut in a mountain shape and the tip of the lower electrode 4 is cut obliquely.
[0014]
2 (a) and 2 (b), the cathode spots 3a and 4a of the upper electrode 3 and the lower electrode 4 are located on the rear side of the cathode spot 3a of the upper electrode 3 relative to the welding direction. 1, (b), and (c), although the tilt angle of the molten pool 10a is smaller than that shown in the embodiment of FIGS. Before the overlap portion of the molten metal 10 is formed on the side, the lower wall 11a side of the narrow groove 11 can be sufficiently melted by the arc of the lower electrode 4.
[0015]
The present invention is not limited to the above embodiment, and the cross-sectional shape of the electrode structure 6 may be other than the shape shown in FIG. Of course, various modifications can be made within the range not to be performed.
[0016]
【The invention's effect】
As described above, according to the TIG welding torch for horizontal welding according to the present invention, an electrode structure in which an elongated flat plate-like insulating plate arranged horizontally is held from both the upper and lower sides by a strip-like upper electrode and lower electrode. In the TIG welding torch for horizontal welding, the cathode spot of the upper plate-like upper electrode and the cathode spot of the lower electrode are arranged in a state where the upper electrode and the lower electrode are arranged in parallel to the welding direction of the laterally facing gap. since the cathode spot of an electrode is a structure which is set so as to be positioned on the rear side of the welding direction than the cathode spot of the lower electrode, it exhibits the following such excellent effects.
(1) When a narrow groove is welded sideways, the cathode spot of the upper electrode and the lower electrode is misaligned, so the molten pool is formed to tilt backward with respect to the welding direction, so it hangs down from the upper side. Before the overlap portion is formed on the lower wall side of the narrow groove by the molten metal, the lower wall side can be sufficiently melted by the arc of the lower electrode, and the welding accuracy can be improved.
(2) Cut the tip of the upper electrode diagonally backwards toward the tip so that the leading-edge cathode spot is located on the rear side of the welding direction, and weld the tip of the bottom electrode to the leading -edge cathode spot. By adopting a configuration that is cut obliquely forward toward the tip so as to be located on the front side of the direction, the dimension between the cathode spots can be increased, and the inclination angle of the molten pool can be increased. The degree of metal drooping can be greatly reduced.
[Brief description of the drawings]
1A and 1B show an embodiment of a TIG welding torch for lateral welding according to the present invention, in which FIG. 1A is a schematic side view of a use state, and FIG. (C) is an AA arrow view of (A).
2A and 2B show another embodiment of the present invention, in which FIG. 2A is the tip of the electrode structure when the tip of the lower electrode is center-cut in a mountain shape as compared with FIG. (B) is an enlarged plan view of the vicinity of the tip of the electrode structure when the tip of the upper electrode is center-cut in a mountain shape as compared with FIG. 1 (b).
FIG. 3 shows an example of a TIG welding torch for lateral welding, where (A) is a schematic view of the usage state, (B) is an enlarged view taken along the B-B direction of (A), and (C) is (B). ).
[Explanation of symbols]
1 Insulating plate 3 Upper electrode 3a Cathode spot 4 Lower electrode 4a Cathode spot 6 Electrode structure

Claims (2)

In a TIG welding torch for horizontal welding having an electrode structure in which an elongated flat plate-like insulating plate is sandwiched from above and below by a strip plate-like upper electrode and a lower electrode, the cathode of the strip plate-like upper electrode In the state where the upper electrode and the lower electrode are arranged in parallel with the welding direction of the laterally sandwiched groove , the upper electrode and the lower electrode are located on the rear side in the welding direction with respect to the lower electrode. A TIG welding torch for transverse welding, characterized by having a configuration set to be positioned. Cut the tip of the upper electrode diagonally rearward toward the tip so that the most advanced cathode spot is located on the rear side in the welding direction, and the tip of the lower electrode is cut on the front side in the welding direction. The TIG welding torch for sideways welding according to claim 1, wherein the TIG welding torch is cut obliquely forward toward the tip so as to be positioned at the top .

Images