JPS60130478A - Automatic horizontal welding of aluminum alloy - Google Patents

Abstract

PURPOSE:To improve efficiency in one-side horizontal oscillating welding of the horizontal aperture of a vertical face by setting the direction of a torch at a specific angle range with respect to the plate surface and the bottom face of the groove and setting the vertical oscillating direction at a specific angle range as well thereby increasing the amt. of deposition and decreasing the number of weld layers. CONSTITUTION:The base 2 of the horizontal aperture of a vertical face 1 is made horizontal and the top face 2 is sloped divergently. The angle alpha of inclination of a torch with respect to the base 2 viewed from the side face of the face 1 is set at 0-30 deg.. The angle beta between the locus where the oscillating 7 direction of the tip of the torch viewed from the direction perpendicular to the plate face 1 is downward in the advancing direction of welding and upward in the direction opposite to the advancing direction of welding and the weld line is set at 30-60 deg.. The angle gamma with the existing weld line viewed from the face 1 direction perpendicular to the weld line is set at 70-110 deg.. The amt. of the weld metal layer which does not flow down increases and the number of the weld layers is decreased in this case. The efficiency is thus improved.

Description

[Detailed description of the invention] The present invention relates to a horizontal automatic welding method for aluminum alloys.

Conventionally, gas-shielded arc welding has been used for horizontal automatic welding of aluminum alloys, but in horizontal welding, the influence of gravity on the molten metal is greater than in downward welding, so a large amount of molten metal is placed at one time. It is not possible. If more than a certain amount of molten metal is placed, the molten metal will sag due to gravity and cause welding defects.

In conventional welding methods, in order to avoid the above problems, welding is performed at a fairly high speed, so the amount of weld metal in each bead is small and the number of welding layers is large compared to the thickness of the material to be welded, resulting in poor efficiency.

The present invention performs riving welding to prevent molten metal from dripping during horizontal automatic welding of aluminum alloys.
This provides a highly efficient horizontal automatic welding method for aluminum alloys with a small number of layers using a relatively large current and a large amount of weld metal. In the method of performing riving welding from one side by automatically moving the welding head along the welding direction, the angle α between the welding wire and the lower groove surface as seen from the welding direction is
0 to 30 degrees, and the angle between the welding line and the trajectory such that the swing direction of the welding wire tip when viewed from the direction perpendicular to the plate surface is downward in the welding direction and upward in the opposite direction to the welding direction. β is 30 to 60 degrees, and the angle γ between the welding wire and the weld line in the direction opposite to the welding direction when viewed from a direction perpendicular to the weld line and parallel to the plate surface is 70 to 110 degrees. This is a characteristic horizontal automatic welding method.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described with reference to preferred embodiments thereof, which are illustrated in the accompanying drawings.

In Figure 1, a groove 2 is provided in an aluminum alloy workpiece 1 placed vertically, and a backing material 3 made of the same material is attached to the back side of the workpiece 1, and a riving device for welding wire 5 is installed. This figure shows a state in which a welding torch 4 is fixed to a welding cart equipped with a welding truck, and a welding wire 5 is automatically fed to perform welding. Figure 2 shows groove 2 provided in material 1 to be welded.
This figure shows the angular relationship between the welding wire 5 and the material to be welded 1 when the second layer is further welded after the peat 6 is placed by weaving welding the first layer.

The operation of this horizontal automatic welding device will be explained as follows. The angle α between the welding wire and the lower groove surface when viewed from the welding direction, and the swing direction of the welding wire tip when viewed from the direction perpendicular to the plate surface are downward in the welding direction and opposite to the welding direction. Then, the angle β between the upward trajectory and the welding line is the angle between the welding wire and the welding line in the direction opposite to the welding direction when viewed from a direction perpendicular to the welding line and parallel to the plate surface. When welding is performed by combining conditions such as angle γ, weaving width (1 to 10 Nn), and riving period (03 to 1 seconds/cycle) depending on the plate thickness and groove shape, the results shown in Figures 3 and 4 are obtained. A trajectory like number 7 is obtained, and the arc point periodically moves along the front edge of the molten pool as welding progresses, forming a sound weld bead.

In horizontal welding, if the solidification rate of the weld metal is not increased, the surface tension will overcome gravity and cause welding defects to sag. However, if live welding is performed under appropriate conditions, the welding speed, which is the guideline for the cooling rate, will be reached. By adding the riving speed, the cooling rate of the weld metal becomes faster. Therefore, it is possible to perform highly efficient welding with a large amount of weld metal and a small number of weld layers by slowing down the traveling speed of the welding device.

In addition, with this welding method, the penetration is deep, so there is less possibility of welding defects occurring, and the appropriate range of welding conditions is wide, so welding can be more stable than with conventional methods.

Figure 5 is a cross-sectional view of the welded area when the first layer is weaved and the second layer is riving welded, but in this case it is a corner! If the angle is less than 30 degrees, arcs are likely to occur in the molten metal, and the penetration of the lower groove surface will be deep, or the upper groove surface will not be directly exposed to the arc, so the inner surface of the upper groove will have poor penetration. Easy to do. If the angle exceeds 60 degrees, the slope of the molten metal becomes a dog, making it easier for the molten metal to flow downward, and although the weld penetration on the upper groove surface becomes deeper, the molten metal flows downward.
The weld penetration on the lower groove surface becomes shallower, further deteriorating the shape of the bead. Furthermore, if the angle α is smaller than 0 degrees, there will be insufficient penetration of the underside of the groove, and if it exceeds 30 degrees, the molten metal will flow to the front side of the groove, resulting in poor bead shape. Based on the above, it is preferable that α be in the range of 0 to 30 degrees and β be in the range of 30 to 60 degrees.

Next, in Fig. 4, even if the angle γ is less than 70 degrees, 11
Since shielding deteriorates even if the angle exceeds 0 degrees, a range of 70 degrees to 110 degrees is preferable for γ.

As a result, according to the present invention, by increasing the amount of weld metal in the bead, it is possible to reduce the number of layers, thereby increasing welding efficiency, and reducing defects such as poor penetration.

A specific series of horizontal welding methods performed by the method of the present invention will be shown.

With the groove shape and lamination procedure shown in Figure 6, horizontal automatic welding of aluminum alloy was carried out under the following conditions. 2. Good welding with good workability, high efficiency, and no welding defects was obtained. A cross-sectional macro photograph of the welded area is shown in the reference figure.

Welding wire; wire diameter for gas shielded arc 2. o
mm Shielding gas: Mixed gas of argon and He gas 40~604/# Plate material: 60W, A3083 (aluminum alloy) Backing material: Same material as plate material Welding wire angle: α=θ~30? β=40~4dust=
85゜Wire swing width; 4~6m+++ Zirle; O, 5~0.6 see/cy
cle welding conditions;

[Brief explanation of drawings]

Figure 1 is a schematic side view of horizontal automatic welding of aluminum alloy, Figure 2 is a side view of the welding part showing the angular relationship between the welding wire and the workpiece in the welding method of the present invention, and Figure 3 is the riving trajectory. Fig. 2 is a front view, Fig. 4 is a longitudinal sectional view of the welded part showing the angular relationship between the welding wire and the workpiece, Fig. 5
The figure shows the welding condition when the angular relationship between the welding wire and the part to be welded is changed. Area ■ indicates poor penetration, ■ indicates sound molten metal, and ■ indicates dripping of molten metal. The figure is an explanatory diagram of the groove shape and lamination procedure in a specific example of the welding method of the present invention. 1: Material to be welded, 2: Groove surface, 3: Backing material, 4: Welding torch, 5: Welding wire, 6: Welding part (first layer), 6a: Weld metal, 7: Riving trajectory. 77- (λ鴫□- ,l Oj,- Procedural amendment (method) % formula % Display of case 1981 Patent application No. 239368 Name of invention Related Patent Applicant Address 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Name (
620) Mitsubishi Heavy Industries, Ltd. Agent 1, Delete "A cross-sectional macro photograph of the welded part is shown in the reference drawing" from lines 5 to 6 on page 7 of the specification. 2. As shown in the attached drawings, the reference figures in Figures 5 and 6 will be deleted from the paper.

Claims (1)

[Claims] A method of performing riving welding from one side by automatically moving a welding head along a welding line extending laterally,
The angle α between the welding wire and the lower groove surface viewed from the welding direction is θ ~ 30 degrees, and the swing direction of the welding wire tip when viewed from the direction perpendicular to the plate surface is the downward direction in the welding direction. The angle β between the welding line and the trajectory that is upward in the direction opposite to the traveling direction is 30 to 60 degrees. The angle γ between the welding wire and the welding line in the direction opposite to the welding direction when viewed from a direction perpendicular to the welding line and parallel to the plate surface is 7.
A horizontal automatic welding method for aluminum alloy, characterized by a welding angle of 0 to 110 degrees.