JPS61226185A - Tig arc welding method - Google Patents

Abstract

PURPOSE:To eliminate the welding defect of incomplete penetration, etc. and to increase the reliability by performing the welding by rotating or reversing the electrode of the shape that the tip has the prescribed angle with the shaft centering around the shaft or arranging the plural tips of this electrode to direct for the opposite direction. CONSTITUTION:A generating arc 14 directs for the bisector (theta) of the solid angle of the tip 12 by the tip shape of the electrode 11 of the shape that the tip 12 is ground in conical shape. The arc 14 can surely be directed for the groove inner corner part 17 and the groove inner corner part 17' at the opposite side by generating the arc 14 from the tip 12 of the electrode 11 by rotating the welding torch main body 13 with feeding shielded gas inside the groove 15 from the welding torch main body 13 by inserting inside the welding groove 15 of base matel 16 said electrode 11 which is fitted to the welding torch main body 13, and with preventing incomplete penetration a good welding can be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in the TIG (tungsten inert welding method).

[Prior art]

Conventional TIG welding involves welding as shown in Figure 8.
：Using a tungsten electrode 1 which is fixed to the welding torch and whose tip 2 is polished into a conical shape, the welding torch body 3 is connected to the base material 6.
While supplying shielding gas into the welding groove 5, an arc 4 is generated from the conical apex of the tip 2 of the electrode 1 to weld the groove 5.

K, who performs narrow gap welding, supplies a welding wire (not shown) to the arc 40 portion, melts the wire and the base metal 6,
A method of filling the welding groove 5 with deposited metal is adopted.

(Problems to be Solved by the Invention) In the case of narrow gap TIG welding, the welding torch main body 3 is inserted into the welding groove 5 as shown in FIG. 1, welding defects such as poor penetration often occur.To prevent this, it is necessary to tilt the welding torch body 3 with respect to the welding groove 5, or to shift it from the center of the groove. In order to weld soundly the inner corners 1 of the grooves on both sides, it is necessary to oscillate the welding torch body 3 during welding.At this time, in the inclined 7 rate method of the welding torch body 3, As the depth increases, it is necessary to widen the groove width (1), and the advantages of narrow groove welding are lost. On the other hand, in the parallel movement oscillation method of the welding torch body 3, it is necessary to make the spread of the arc 4 greater than the width of the welding torch body 30, and as a result, the welding current must be made larger than necessary.

The present invention has been made to solve the above-mentioned conventional problems, and aims to provide a TIG welding method that achieves highly accurate and reliable welding without welding defects such as poor penetration. .

[Means for solving problems]

In TIG welding, the present invention uses an electrode whose tip has a predetermined angle with respect to an axis, and rotates the electrode around the axis or inverts the electrode, or uses a plurality of electrodes. This is characterized in that welding is performed with the individual tips facing in opposite directions.

[Effect]

According to the present invention described above, the width of the welding groove is widened,
A directional arc can be generated at the inner corner of the welding groove without increasing the welding current more than necessary, resulting in highly accurate and reliable TIG without welding defects such as poor penetration. Welding can be accomplished.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

Example 1 FIGS. 1 and 2 show a welding situation using the electrode rotation oscillation method. As the electrode 11, for example, as shown in FIG.
As shown in (b), the tip 12 is ground into an oblique conical shape. The electrode 11 having such a shape has a tip 1
2 has a given angle with respect to its axis, the arc 14
is directed in the direction of the solid angle bisector (θ) of the tip 12. After attaching such an electrode 11 to the welding torch body 13 and inserting the welding torch body 13 into the welding groove 15 of the base metal 16, a motor (not shown) is operated while supplying shielding gas from the welding torch body 13 into the welding groove 15. By generating an arc 14 from the tip 12 of the electrode 11 while rotating the welding torch main body 13, the inner corner 17 of the welding groove 15 as shown in FIG. In this way, the arc can be reliably directed to the inner corner 17' of the groove on the opposite side, thereby preventing poor penetration and achieving good welding.

Note that the same effect can be achieved even if the electrode 11 in the first embodiment is reversed and oscillated.

Example 2 Figure 4 is a front view showing the welding situation using the two-electrode method, Figure 5
The figure is a sectional view taken along the line XX in FIG. 4. First, the electrode 11 having the same shape as shown in FIGS.
m, Ilb at the tip 12a.

Attach the welding torch body 13 to the welding torch body 13 so that the oblique conical slopes of the electrodes 12b face each other, and insert the welding torch body 13 into the welding groove of the base metal 16 to remove the tip I of each of the electrodes 11m and Ilb.
Ja, 12b is directed toward the groove inner corners 17, 17'. When welding is performed while supplying shielding gas from the welding torch body 13 into the welding groove 15 in this state, the arcs 14m and 14b of the two electrodes 11h and Ilb always completely cover the inner corners 17 and 11' of the groove. Can be melted,
Furthermore, since the central portion of the groove also falls within the spread range of both arcs 14h and 14b, sound welding can be performed throughout the entire groove.

In the second embodiment, when a multi-electrode type is adopted, it is also possible to alternately apply current to each electrode in a flow pattern.

In each of the above embodiments, the electrodes shown in FIG. 3(a) t(b
) was used, but the shape is not limited thereto.

For example, as shown in FIGS. 6(a) and (b), the tip 12
As shown in FIGS. 7(a) and 7(b), the electrode 11 is formed by bending the tip 12 by bonding.
You may use each.

〔Effect of the invention〕

As detailed above, the TIG welding method of the present invention has various effects listed below.

(1) By shaping the tip so that the direction of arc generated from the tip of the electrode is at a predetermined angle with respect to the electrode axis, penetration into the wall of the welding groove on the side where the arc is directed becomes deeper. Welding defects such as poor penetration can be prevented.

(2) By rotating or reversing the electrode of the above shape, the direction of shear arc can be directed alternately to the groove walls on both sides (the inner corner of the groove), so that both sides of the groove walls are always welded soundly. It is possible to do so.

(3) By using a plurality of electrodes with the above shape and changing the direction of the arc of each electrode, it is possible to reliably penetrate both side walls of the groove without rotating or reversing the electrodes. However, stable and sound welding can be performed.

[Brief explanation of the drawing]

Figures 1 and 2 are front views showing welding by the rotary oscillation method in Example 1 of the present invention, Figure 3 (,) is a front view of the electrode used in Example 1, and Figure (b) is a side view of the same figure (for illustration), FIG. 4 is a front view showing the welding situation by the two-electrode type in Example 2 of the present invention, FIG. 5 is a sectional view taken along the line X-X in FIG. Figure 6(a) is a front view showing another form of the electrode used in the present invention, and Figure 6(b) is a front view of another form of the electrode used in the present invention.
), FIG. 7(,) is a front view showing another form of the electrode used in the present invention, FIG. 7(b) is a side view of FIG. 8(a), and FIG. It is a front view showing the situation of TIG welding. 11, 11 a, I l b-electrode, 12.12
m. 12b...Tip, 13-...Welding torch body, 14
゜14*, 14b... Arc, 15... Welding groove,
16-... Base material, 11, 17'... Groove inner corner. Applicant's sub-agent Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 4 Figure 5 - Figure 3 Figure 6 S7 Figure Whistle 8 Figure ν, 114 March 1920 Japan Patent Office Commissioner Michibe Uga 1. Indication of the case Japanese Patent Application No. 60-65294 2. Name of the invention TIG @ Contact method 3. Person making the amendment Relationship to the case Patent applicant (620) Mitsubishi Heavy Industries, Ltd. 4. Successor administrator 5. Spontaneous amendment 7. Details of the amendment (1) Figure 1 of the drawings will be corrected as indicated in red on the attached sheet. Figure 4 of the drawings will be corrected as marked in red on the attached sheet. Figure 1 Figure 2

Claims (1)

[Claims] In TIG welding, an electrode whose tip has a predetermined angle with respect to the axis is used, and the electrode is rotated about the axis or reversed, or multiple electrodes are A TIG welding method characterized by performing welding by arranging the welds facing in opposite directions.