JPS6038238B2 - MIG welding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an MIC welding method for welding and joining one welding material having good thermal conductivity, such as copper.

Conventionally, this type of MIG welding method, as shown in FIGS. 1 and 2, involves two materials to be welded, such as steel materials a
A welding wire (also called a welding nozzle) that also serves as an electrode is inserted into the welding part that forms the one-shaped groove, and at the same time an inert gas is supplied. Then, the welding wire 1 is melted and joined to form a welded metal part c.
It is designed to form a

However, in the above-mentioned MIG welding method, as is clear from FIG. 1, since the weld metal part c is formed in a substantially V-shape, when it is subjected to a tensile test after welding is completed,
As shown in the graph of Fig. 2, the welding start side, that is, the welded part C, is the curve A, and the curve is 1.
The welding end side of the joint, that is, the welding part C2, has a large change from the curved line, and when used for a coil as an electric conductor, for example, the welded part has non-uniform strength, which is disadvantageous.

In particular, in the conventional MIG welding method, extra buildup is applied to release latent heat input during welding, so after welding is completed, this extra buildup removal work and the welding wire used as extra buildup can be done in a time-consuming and economical manner. Not only is this wasteful, but the penetration amount of the welding groove in the welded parts a and b differs greatly between the start and end of welding, so the range of material deterioration due to the width of the weld metal and welding heat input is large. There is a possibility that there may be some differences.

In addition, in the MIG welding method using the type 1 joint described above, when this joint part is subjected to tensile stress, the V-shaped joint part will elongate unevenly, making it difficult to apply it to materials with good heat conduction properties. These uneven elongations become a problem. On the other hand,
In addition to the conventional MIG welding method using a type 1 joint, for example, MIG welding methods using a V-shaped joint or a Y-type joint have already been proposed, but these also have MIG welding methods using a type 1 joint described above.
Like the IG welding method, it has the disadvantage of non-uniform elongation.

In view of the above-mentioned points, the present invention forms the welding joints of two welded members into a trapezoid with a wide lower part and a narrow upper part, and each abutment member is installed on the outer periphery of this welding groove, After that, a welding wire is inserted into the welding groove, and at the same time an inert gas is supplied to enable welding, thereby connecting the welding start side and welding end side of the welding trapezoidal joint of the welded material. MI aims to reduce the displacement of elongation to produce uniform elongation, and at the same time to suppress the range of material deterioration to a small extent.
This provides a G welding method.

Hereinafter, the present invention will be described with reference to an illustrated embodiment. Third
In the figures 1 and 5, reference numerals 1 and 2 indicate two welded parts having good heat conductivity, such as steel materials, and each end of these two welded parts 1 and 2 has a welding groove. The welding groove portion 3 is formed in a trapezoidal shape with a wide bottom and a narrow top.
A side support member 4 and a bottom support member 5 are attached to both sides and the bottom of the housing so as to surround them from the outside.

Note that if the plate width of the members 1 and 2 to be welded is W and the plate thickness is T, it is suitable for vertical welding where the plate thickness T is smaller than the plate width W, but if the plate width W is Even when the thickness is significantly larger than the thickness T, or when both the plate thickness W and the plate thickness T are large, welding can be performed by weaving the welding wire 16 or by using multiple electrodes.

Furthermore, although the welding groove portion 3 is formed into a trapezoid with a wide bottom and a narrow top, the lower groove width a is approximately 1.1 to 5. It is desirable that the width of the groove be within the range of 100 degrees, and the selection of these groove widths is determined by the material, plate width W, plate thickness T, thermal conductivity, welding heat input energy, etc.
Next, a welding wire 6 and an inert gas (not shown) are inserted into the welding groove 3, and the welding wire 6 is energized and melted, as shown in FIG. To,
A welded metal portion 7 is formed.

That is, in the present invention, the shape of the weld joint part 3 of the two welded part villages 1 and 2 is formed into a trapezoid with a wide bottom and a narrow top, and each abutment member 4, 5, and then inserting a welding wire 6 which also serves as an electrode into the welding joint part 3,
When an inert gas is supplied and current is applied at the same time, the amount of penetration at the welding joint is approximately constant at the start and end of welding.
The width of the welded metal portion 7 becomes constant, and the range of material deterioration due to welding heat input is reduced. To explain this with respect to the graph in Fig. 2, the welding start side with the trapezoidal groove, that is, the welding part 7a, becomes the B curve, and the welding end side with the trapezoidal groove becomes the B2 curve, and both curves B and B2. Since this causes almost no change, a welded portion 7 of uniform strength is produced. On the other hand, in the supply of inert gas to the trapezoid joint during welding, since the upper development 3a, which is an escape port for the inert gas, is formed narrowly, the shielding effect is good, and the supply of inert gas from the lower joint 3b to the upper part is narrow. Even if the welding moves to
. As described above, according to the present invention, the shape of the welding groove portion 3 of the two welded portions 2 is formed into a trapezoid with a wide bottom and a narrow top, and the outer periphery of the welding groove portion 3 is Paste the welding parts 4 and 5, and then attach the welding point part 3.
Since the welding wire 16 is inserted into the welding wire 6 and at the same time an inert gas is supplied for welding, there is no need for welding latent heat input and release due to excess welding, and welding heat input can be used effectively. Therefore, the range of material deterioration can be narrowed, and
It has excellent effects such as being able to reduce changes in the elongation of the welded part and achieve uniform elongation.

[Brief explanation of drawings]

Fig. 1 is a diagram for explaining the conventional MIG welding method, Fig. 2 is a graph showing the relationship between stress and elongation of the welded part welded by the MIG welding method, and Fig. 3 is a diagram for explaining the conventional MIG welding method.
FIG. 4 is a perspective view for explaining the G welding method, FIG. 4 is a sectional view of the same, and FIG. 5 is a perspective view of a member to be welded according to the present invention. 1, 2... member to be welded, 3... welding groove, 4, 5...
- Welding member, 6...welding wire one. Shoichi Ticket 2 Tsuyoshi 3 Elephant 4 Elephant Ku

Claims (1)

[Claims] 1. Form the welding grooves of the two welded parts into trapezoidal shapes with a wide bottom and a narrow top, attach each padding member to the outer periphery of this welding development area, and then attach the welding grooves to the welding grooves. A MIG welding method characterized by inserting a welding wire and simultaneously supplying an inert gas to perform welding.