JPH0557434A - Automatic horizontal one-side welding method - Google Patents

Abstract

(57) [Abstract] [Purpose] The first layer of the lateral groove groove is automatically welded in a precise single pass to form a good back bead to improve welding quality and reduce welding cost. [Structure] The groove surface of the lower base material 1 which is arranged substantially vertically is substantially perpendicular to the plate surface, and the upper base material 2 is angled to form a lateral groove 3 to form about 3 to 8 mm. A root spacing 4 is taken, and a backing material 5 is applied to the surfaces of the base materials 1 and 2 on the back side of the groove at the groove center, and a lower base material is placed on the front side of the groove from the groove surface to its upper end. The front padding material 6 is applied so as to be at a position of about 5 mm, and further, the metal powder 7 in an amount corresponding to the size of the root interval 4 is sprinkled into the lateral groove groove 3 and the consumable gas shield is applied from the groove front surface side. Perform arc welding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horizontal one-sided automatic welding method.

[0002]

2. Description of the Related Art Conventionally, in single-sided automatic welding of a horizontal butt joint, as shown in the sectional view of FIG. 2, the groove surface of the lower base material 11 is substantially perpendicular to the plate surface, and the groove of the upper base material 12 is formed. The faces are angled to form a lateral groove 13 between them, and an appropriate route interval 14 is provided so that the back bead can easily come out.
Is provided, and the backing material 15 is applied to the groove center on the back side of the lateral groove 13, and the upper end of the backing material 16 for receiving molten metal is applied to the surface of the lower base material 11 on the front side. Wire 1 of welding torch 18 for consumable gas shielded arc welding from the groove side
Welded by 9.

However, in order to weld the first layer in one pass with the lateral groove groove 13 having such a root interval 14, it is necessary to secure the amount of molten metal required to fill the root interval 14, There is a great need for horizontal butt joints of large structures where it is difficult to secure the groove precision and the groove fluctuation is large. However, in horizontal welding, the molten metal tends to flow downward and droop down.Therefore, the rod method is used to swing the wire up and down to prevent the molten metal from drooping down by the arc force. If the gap 14 is larger than 4 mm and the standard or higher current value is used for welding, the molten metal tends to flow more and more downward, leading to the front of the groove and the regular welding bead cannot be placed. There is a limit to realizing. Therefore, the first layer is set to 1 in the lateral groove 13 with a large root interval 14.
In order to weld in a pass, it is necessary to find a welding method that blocks the flow of the molten metal and allows the molten metal to sufficiently conform to the upper surface of the groove.

[0004]

SUMMARY OF THE INVENTION The present invention has been proposed in view of such circumstances, and it is possible to automatically weld the first layer of the lateral groove groove in a single pass to obtain a good back bead. It is an object of the present invention to provide a horizontal one-sided automatic welding method that can be formed and can improve welding quality and reduce welding cost.

[0005]

To this end, according to the present invention, the groove surface of the lower base material, which is arranged substantially vertically, is substantially perpendicular to the plate surface, and the upper base material is angled to form a horizontal groove. With a root interval of about 3 to 8 mm, and a backing material is applied to the center of the groove on both base material surfaces on the back side of the groove, and the lower base material surface on the front side of the groove from the groove surface. Apply the front cover material so that the upper end is at a position of about 5 mm, and further sprinkle an amount of metal powder corresponding to the size of the root interval in the above-mentioned lateral groove, and consume the consumable gas shield from the front side of the groove. Characterized by performing arc welding.

[0006]

With the above-described structure, the first layer of the lateral groove groove can be automatically welded accurately in one pass to form a good backside bead, thereby improving the welding quality and reducing the welding cost. It is possible to obtain a horizontal one-sided automatic welding method capable of performing the above.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the horizontal single-sided automatic welding method of the present invention will be described with reference to the sectional view of FIG.
And are arranged almost vertically, and the groove angle of the lower base metal 1 is almost 0.
Degree, that is, approximately perpendicular to the plate surface, the upper base metal 2 is 35 to 45
The groove angle of 4 degrees is taken to form a lateral groove 3 between the two base materials, and a root distance 4 within the range of 3 to 8 mm is set as small as possible. The backing material 5 is attached along the groove center line on the rear surface of the base material, and the front backing material 6 for preventing the molten metal from flowing down is attached to the surface of the lower base material 1 at the upper end thereof from the lower groove surface 4 Mount so that it is located at a height of ~ 5 mm. Then, when the route interval 4 exceeds at least 4 mm, the metal powder 7 is sprayed to the full extent of the groove in the groove surrounded by the backing material 5 and the front patch 6. In this state, consumable gas shield arc welding is performed by the wire 9 of the welding torch 8 arranged on the front side of the lateral groove groove 3. The welding torch 8 has a vertical angle that is substantially parallel to the upper groove surface and a receding angle that forms an angle of 40 to 50 degrees with the plate surface in the traveling direction, and performs welding while swinging vertically.

In this manner, for example, the wire 9 is 1.4
In the case of mm diameter, automatic welding is performed using a current value of 350 to 380 A, and the welding speed is controlled to an appropriate value by the route interval 4. The welding speed varies depending on the plate thickness and laminating method, but the plate thickness of the base materials 1 and 2 is 15 to 25 mm, and the root interval 4 is 3 to 8 mm.
The range is 9 to 15 cm / min. Then, the front of the molten metal is blocked by the metal powder 7 held in the groove by the front cover material 6, and a stable molten pool can be obtained even if the amount of the molten metal increases a little, and the route interval of about 8 mm is obtained. Also in No. 4, the first layer was welded accurately in one pass, and a good backside bead could be obtained.

[0009]

In summary, according to the present invention, the groove surface of the lower base material, which is arranged substantially vertically, is substantially perpendicular to the plate surface, and the upper base material is angled to form a lateral groove. About 3 ~
With a root interval of 8 mm, a backing material is applied to both sides of the base material on the back side of the groove at the center of the groove, and on the front side of the groove, a position of about 5 mm from the groove surface to the lower base material surface By applying a front cover material so that the amount of metal powder commensurate with the size of the root interval is further sprayed in the lateral groove groove and performing consumable gas shield arc welding from the groove surface side, A horizontal single-sided automatic welding method that can automatically weld the first layer of a horizontal groove groove in a single pass to form a good backside bead, improve welding quality and reduce welding cost. Therefore, the present invention is extremely useful in industry.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a horizontal single-sided automatic welding method of the present invention.

FIG. 2 is a cross-sectional view showing a conventional welding method.

[Explanation of symbols]

 1 Lower base metal 2 Upper base metal 3 Horizontal groove groove 4 Route interval 5 Backing material 6 Front patching material 7 Metal powder 8 Welding torch 9 Wire

Claims (1)

[Claims] 1. A root of about 3 to 8 mm in which the groove surface of the lower base material arranged substantially vertically is substantially perpendicular to the plate surface and the upper base material is angled to form a lateral groove. Take an interval,
In addition, apply a backing material to the center of the groove on both sides of the base material on the back side of the groove, and place a backing material on the front side of the groove so that the upper end of the base material surface is about 5 mm from the groove surface. The horizontal sided one-sided automatic welding method, characterized in that the consumable gas shield arc welding is performed from the front side of the groove by further spraying an amount of metal powder corresponding to the size of the root gap in the horizontal groove. ..