JP2003211269A - Equipment and method of consumable electrode type arc welding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide consumable electrode type arc welding equipment in which an excellent weld bead with no defect is available even when the position of supplying a filler wire is horizontally dislocated in a weld line direction due to the influence of the bend or the like of a filler wire in the forwarding direction of a consumable electrode wire. <P>SOLUTION: A weaving action with a rocking motion is given to a welding torch 12 with respect to a work to be welded so that the feeding position P1 of the consumable electrode wire is rocked and moved back and forth in both directions with respect to the center line X of welding, and the rocking width W2 at the feeding position P3 of the filler wire is smaller than the rocking width W of the feeding position P1 of the consumable electrode wire. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a consumable electrode type arc welding apparatus and a consumable electrode type arc welding method, and more particularly to a consumable electrode type arc welding method for weaving using two welding wires, a consumable electrode wire and a filler wire. The present invention relates to a welding device and a consumable electrode type arc welding method.

[0002]

2. Description of the Related Art As a welding method using two welding wires of a consumable electrode wire and a filler wire, for example, a consumable electrode type arc welding method disclosed in Japanese Patent Laid-Open No. 3-275280 is known.

In this welding apparatus using the consumable electrode type arc welding method, two wires, a consumable electrode wire and a filler wire, are inserted into the shield nozzle and an arc is generated by the consumable electrode wire. At this time, the filler wire is inserted into the molten pool, and a part of the welding current flowing from the consumable electrode wire to the base material is shunted to be guided to the filler wire and merged with the ground end of the welding power source.

In such a welding method, since the directions of the currents flowing through the consumable electrode wire and the filler wire are opposite to each other, the magnetic fluxes generated in the consumable electrode wire and the filler wire repel each other, and the arc generated from the consumable electrode wire is generated. Is tilted in the opposite direction to the filler wire. Therefore, even if the filler wire is brought close to the consumable electrode wire, the filler wire can be melted and supplied for other purposes without being blown by the arc.

By adopting such a welding method,
In welding of carbon steel, alloy steel, aluminum, etc., even if the welding speed is increased, it is possible to perform welding at high speed and high efficiency with good workability. In addition, by inserting a filler wire into the molten pool, the temperature of the molten pool is kept low, the occurrence of puckering phenomenon that disturbs the weld bead, black powder adhesion (oxide adhesion), and solidification crack susceptibility are suppressed. It can be reduced.

When a wide bead is required in arc welding such as multi-layer welding or overlay welding, welding is performed while swinging the welding torch left and right with a predetermined swing width in the longitudinal direction (welding center line) of the welding. An operation called weaving is performed. By the weaving operation, a large weld metal can be obtained and a weld bead having a good shape can be obtained. Further, a function called arc sensing that follows a welding line can be realized by measuring changes in current, voltage, etc. during welding while performing a weaving operation.

[0007]

In an arc welding method using two wires, a consumable electrode wire and a filler wire, it is usually deeper behind the electrode wire in the traveling direction (on the delayed side in the welding traveling direction). Since the molten pool is formed, the filler wire is supplied to the molten pool at a position that is behind the consumable electrode wire by a predetermined amount in the welding proceeding direction.

When the filler wire is bent, it is difficult to supply the electrode wire and the filler wire on the same line in the welding line direction. In many cases, the supply position of the filler wire is displaced from the supply position of the consumable electrode type wire in the direction perpendicular to the welding direction (direction crossing the welding center line left and right).

When fillet arc welding is performed by swinging the welding torch in a direction perpendicular to the welding direction (weaving operation) in such a state, the filler wire forms a relatively shallow region of the molten pool and the base metal. Will be supplied near the boundary surface. As a result, the filler wire may not be completely melted in the molten pool and may remain unmelted inside the deposited metal.

According to the present invention, due to the influence of the bending of the filler wire on the traveling direction of the consumable electrode wire,
An object of the present invention is to provide a consumable electrode type arc welding apparatus and a consumable electrode type arc welding method capable of obtaining a good welding bead without defects even in a state where the filler supply position is deviated from side to side with respect to the welding line direction. .

[0011]

According to a first aspect of the present invention, there is provided a consumable electrode wire supply section for supplying a consumable electrode wire to a welding target through a welding torch, and a weld pool for the welding target through the welding torch. So that the filler wire supply unit that supplies the filler wire to the and the consumable electrode wire oscillates to the left and right with respect to the welding center line, and the lateral swing width of the filler wire becomes smaller than the lateral swing width of the consumable electrode wire. And a oscillating motion means for oscillating the welding torch with respect to the object to be welded. (2) According to the invention of claim 2, in the consumable electrode type arc welding apparatus according to claim 1, the swinging motion means is such that the consumable electrode wire and the filler wire both swing and move to the left and right sides with respect to the welding center line. In addition, the welding torch is rotated so that the rotation angle of the welding torch centering on the side lagging the welding progress direction with respect to the consumable electrode wire increases as the consumable electrode wire moves away from the welding center line. . (3) According to the invention of claim 3, in the consumable electrode type arc welding device according to claim 1, the swinging motion means has a center of welding as a center of rotation with a side of the consumable electrode wire being a lagging side in a welding advancing direction as a center of rotation. It is characterized in that the welding torch is rotated while being kept on the line, and the consumable electrode wire is swingably moved to the left and right sides with respect to the welding center line. (4) The invention according to claim 4 is the consumable electrode type arc welding apparatus according to any one of claims 1 to 3, wherein at least the welding speed, the welding current, the welding voltage, the torch angle, and the consumable electrode wire are the welding center line. A parameter input section for inputting the movement width and movement frequency that swings to the left and right sides,
And a control means for controlling the operation of the welding torch including the operation by the swing motion means based on the parameter input by the parameter input unit. (5) The invention of claim 5 is a consumable electrode wire supply section for supplying a consumable electrode wire to a welding target through a welding torch,
The present invention is applied to a welding method using a consumable electrode type arc welding apparatus that includes a filler wire supply unit that supplies a filler wire to a molten pool to be welded through a welding torch. And
Swinging the welding torch with respect to the welding target so that the consumable electrode wire oscillates to the left and right with respect to the welding center line and the horizontal swing width of the filler wire becomes smaller than the horizontal swing width of the consumable electrode wire. Is characterized by. (6) The invention according to claim 6 is the consumable electrode type arc welding method according to claim 5, in which both the consumable electrode wire and the filler wire are oscillated to the left and right sides with respect to the welding center line, and the consumable electrode is used. It is characterized in that the welding torch is rotated so that the rotating angle of the welding torch centering on the side behind the consumable electrode wire in the welding proceeding direction increases as the wire moves away from the welding center line. (7) The invention according to claim 7 is the consumable electrode type arc welding method according to claim 5, wherein welding is performed while keeping the rotation center on the welding center line with the side behind the consumable electrode wire in the welding proceeding direction being the rotation center. It is characterized in that the torch is rotated to swing the consumable electrode wire to the left and right sides with respect to the welding center line. (8) The invention of claim 8 is applied to a multi-layer welding method using a consumable electrode type arc welding apparatus, wherein lower layer welding is performed by the consumable electrode type arc welding method of claim 7, and upper layer welding is claimed. Item 6 is performed by the consumable electrode type arc welding method. (9) The invention of claim 9 is applied to an arc welding condition determining device used in the consumable electrode type arc welding device according to any one of claims 1 to 3, and at least a welding speed, a welding current, a welding voltage, Based on the torch angle, the input part for inputting the moving width and the moving frequency at which the consumable electrode wire swings to the left and right sides with respect to the welding center line,
And a calculation means for calculating the swing angle of the welding torch by the swing motion means.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a consumable arc welding apparatus according to the present invention will be described in detail below with reference to FIGS.

FIG. 1 shows the overall construction of a consumable electrode type arc welding apparatus according to the present invention applied to a welding apparatus using a welding robot. The welding robot 10 is, for example, a 6-axis articulated robot. The welding robot 10 has a hand portion 11 at the tip of the arm. The hand portion 11 is provided with a welding torch 12 for consumable electrode type arc welding via a wire supply tube 13.

An electrode wire feeder 14 and a filler wire feeder 15 are attached to the welding robot 10. The electrode wire feeder 14 supplies the consumable electrode wire Y1 from the electrode wire supply reel 16 to the welding torch 12 through the wire supply tube 13. The filler wire feeder 15 supplies the filler wire Y2 from the filler wire supply reel 17 through the wire supply tube 18 to the welding torch 12.

The electrode wire feeding device 14 controls the feeding of the consumable electrode wire Y1 by the welding power source / control device 19. The filler wire feeding device 15 controls the feeding of the filler wire Y2 by the filler control device 20. The positive terminal 19A of the welding power source / control device 19 is electrically connected to the consumable electrode wire Y1, and the negative terminal 19B is grounded to the welding target (base materials B1 and B2) and the filler wire Y2.

The welding power source / control device 19 and the filler control device 20 operate based on an arc control command and a filler control command input from a computer type robot control device 21, which is a higher-level control device.

The robot controller 21 is the welding robot 10.
To control. An input device 22 with a monitor, which also functions as a teaching pendant, is connected to the robot control device 21. The input device 22 is an input unit for welding parameters, and sends input data to the robot control device 21.

The details of the welding torch 12 will be described with reference to FIGS. The welding torch 12 has an electrode wire delivery nozzle 23 that also serves as an energizing tip and a filler wire delivery nozzle 24.

The electrode wire delivery nozzle 23 and the filler wire delivery nozzle 24 are aligned on the same line in the welding direction indicated by arrow A. Filler wire delivery nozzle 2
No. 4 is on the lagging side in the welding advancing direction from the electrode wire delivery nozzle 23. Therefore, the filler wire Y2 is delivered to the position on the lagging side in the welding advancing direction by a predetermined amount D1 from the consumable electrode wire Y1.

FIG. 3 is a view of the welding torch 12 as seen from directly below. The supply position of the consumable electrode wire Y1 delivered from the electrode wire delivery nozzle 23 is P1, and the supply position of the filler wire Y2 delivered from the filler wire delivery nozzle 24 is P3. The rotation center position P2 of the welding torch 12 is
The consumable electrode wire supply position P1 is set on the delayed side in the welding proceeding direction. For example, as shown in FIG. 4, the consumable electrode wire supply position P1 swings to the left and right with respect to the welding center line X, and the left and right swing width W2 of the filler wire supply position P3 is left and right of the consumable electrode wire supply position P1. The welding torch 12 is oscillated with respect to the welding target so as to be smaller than the swing width (weaving width) W1. This swinging motion is called a weaving motion. The weaving operation is performed by controlling the movement of the welding robot 10 in six degrees of freedom.

In such a weaving type welding method,
It is very difficult to supply the electrode wire Y1 and the filler wire Y2 on the same line in the welding line direction due to bending of the filler wire Y2. In many cases, as shown in FIG. 9, the supply position of the filler wire Y2 is vertical to the welding direction (direction crossing the welding center line left and right) as compared with the supply position of the consumable electrode type wire Y1. , D2 occurs.

In this state, as shown in FIG. 10, the welding torch T is oscillated (weaving operation) in the vertical direction with respect to the welding direction by the swing width W to form the base material B1. When fillet arc welding of B2 is performed, as shown in FIG. 11, the filler wire Y2 is supplied near the boundary surface B4 between the relatively shallow region of the molten pool B3 and one of the base materials B1. It will be.

In such a filler wire supply, the filler wire Y2 cannot be completely melted in the molten pool B3, and as shown in FIG. 12, an unmelted residue B6 occurs inside the weld metal B5. Further, when the supply amount of the filler wire Y2 is increased, the filler wire Y2 collides with the interface portion of the molten pool B3, the filler wire Y2 vibrates, and the welding torch T
Is pushed up. Therefore, welding becomes unstable and welding defects are generated. Therefore, in this embodiment, such a problem is solved by performing the following weaving operation. The details will be described below.

In the welding device according to this embodiment, two types of weaving operations (first weaving operation, second weaving operation) are performed.
Weaving operation) is set. These two types of weaving operations are used properly according to the welding conditions.
Hereinafter, the first weaving operation and the second weaving operation will be described with reference to FIGS. 4 to 7.

(First Weaving Operation) As shown in FIGS. 4 and 5, when the welding torch 12 is moved along the welding line, (1) the consumable electrode wire supply position P1 and the filler wire supply position Both P3 and P3 swing to the left and right with respect to the welding center line X, and (2) as the consumable electrode wire supply position P1 moves away from the welding center line X left and right, welding progresses to the consumable electrode wire supply position P1. Welding torch 12 with rotation center position P2 on the direction delay side as the rotation center
The welding torch 12 is rotated around the rotation center position P2 as the rotation center while moving to the left and right with respect to the welding center line so that the rotation angle of the welding torch increases.

In this weaving operation, the welding torch 1
The rotation center position P2 of No. 2 swings in a direction orthogonal to the welding direction with a width indicated by reference sign D. The welding torch 12 is configured such that the filler wire supply position P3, that is, the filler wire Y2 is located in the welding line center direction with respect to the consumable electrode wire Y1 as the consumable electrode wire supply position P1 is further away from the welding center line X to the left and right. Rotation center position P2 gradually
Rotate relatively around. As shown in FIGS. 5 (a) and 5 (c), the welding torch 12 has a welding center axis having a maximum angle θ at a position where the consumable electrode wire supply position P1 is farthest from the welding center axis X. Tilted with respect to X.

On the other hand, as the consumable electrode wire supply position P1 moves toward the center of the welding line, the inclination angle of the welding torch 12 decreases, and as shown in FIG. When reached, the central axis of the welding torch 12 becomes substantially horizontal to the welding line central line X.

The weaving torch 12 is weaved by alternately repeating the above operation.
The weaving width W1 of the consumable electrode wire supply position P1 is
Consumable electrode wire supply position P1 and torch rotation center position P2
It is expressed by the following equation using the distance L between and. W1 = D + 2L · tan θ (1)

Even when the supply position P3 of the filler wire Y2 is located on the left and right of the consumable electrode wire Y1 in the welding line direction, the first weaving operation causes the filler wire Y2 to move to the boundary between the base metal and the molten pool B3. It is prevented from being supplied to the vicinity. The filler wire Y2 is always favorably supplied to a position near the central region of the molten pool B3. In the first weaving operation, the weaving width can be set relatively large, and the welding bead is suitable for wide welding.

(Second Weaving Operation) In the second weaving operation, as shown in FIGS. 6 and 7, the rotation center position P2 on the lag side in the welding advancing direction with respect to the consumable electrode wire supply position P1. Is performed around the center of rotation. The welding torch 12 is rotated while maintaining the rotation center position P2 on the welding center line X. As a result, the consumable electrode wire supply position P1 is swung to the left and right sides with respect to the welding center line X.

In this case, as shown in FIGS. 7A and 7B, when the consumable electrode wire supply position P1 is farthest from the welding line central axis X, the welding torch 12 is used.
The central axis of is tilted at an angle of θ ′ with respect to the central axis X of the welding line. The weaving width W1 of the consumable electrode wire supply position P1 is expressed by the following equation using the distance L between the consumable electrode wire supply position P1 and the torch rotation center position P2. W1 = 2L · tan θ ′ (2)

Even when the supply position P3 of the filler wire Y2 is located on the left and right in the welding line direction with respect to the electrode wire Y1, this second weaving operation causes the filler wire Y2 to be near the boundary between the base metal and the molten pool B3. Are prevented from being supplied to. The filler wire Y2 is always favorably supplied to a position near the central region of the molten pool B3. In this second weaving operation, the weaving width cannot be set to be too large, but the movement of the welding torch is simple, so that welding at a high welding speed can be accommodated.

The inclination angles θ and θ ′ in the above-mentioned first and second weaving operations are determined by the welding speed, welding current, weaving width (moving width), weaving frequency (moving frequency), shape of the welding target, and the like. It can be determined based on the shape of the pond B3 and the estimated amount of displacement between the two wires. For example, when the weaving width (moving width) is input, since L is an existing value, θ and θ ′ can be determined from the above equations (1) and (2). It is also possible to calculate the weaving width itself from the shape of the welding target and the like, and determine θ and θ ′ based on the calculated weaving width. In this case, the control device 19 functions as a determination device that determines θ and θ ′.

The input device 22 functions as an input unit for inputting parameters such as welding speed, welding current, welding voltage, torch angle, weaving width, and weaving frequency.
The robot controller 21 controls the operation of the welding torch 12 including the weaving operation based on the parameter input by the input device 22.

According to the consumable electrode type arc welding apparatus of this embodiment, the consumable electrode wire moves to the left and right from the welding center line position under the weaving operation in which the consumable electrode wire oscillates left and right with respect to the welding center line. When it is biased to, the filler wire is located closer to the welding center side than the consumable electrode wire portion, and even if the filler wire bends,
The filler wire is not supplied to the boundary region side of the molten pool. Therefore, the filler wire collides with the bottom of the molten pool to cause unmelted residue, or the filler wire vibrates or the welding torch is pushed up, so that good welding can be performed without making the welding unstable. become able to.

In the case of the first weaving operation, the weaving width can be set relatively large and a wide weld bead can be obtained. In the case of the second weaving operation, the weaving width cannot be set too large, but the movement of the welding torch is simple, and it is possible to cope with welding at a high welding speed.

In the multi-layer welding as shown in FIG. 8, the lower layers Ba and Bb having a relatively small bead width are welded by the consumable electrode type arc welding method by the second weaving operation described above, The welding Bc, Bd of the upper layer having a relatively large bead width is performed by the above-mentioned consumable electrode type arc welding method by the first weaving operation.

In addition to the consumable electrode type arc welding apparatus and method according to the present invention, in addition to the above-described embodiment, for example, one preceding wire (consumable electrode wire Y1),
It can be applied in various arc welding methods such as two trailing wires (filler wire Y2).

[0039]

According to the present invention, the filler wire can be stably supplied to the molten pool, whereby the supply amount of the filler wire and the welding speed can be increased.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an overall configuration in which a consumable electrode type arc welding apparatus according to the present invention is applied to a welding robot.

FIG. 2 is a side view of a welding torch used in the consumable electrode type arc welding apparatus according to the present invention.

FIG. 3 is a bottom view of the welding torch used in the consumable electrode type arc welding apparatus according to the present invention.

FIG. 4 is an explanatory view showing a first weaving operation in the consumable electrode type arc welding apparatus according to the present invention.

5A to 5C are explanatory views showing wire supply positions in the first weaving operation.

FIG. 6 is an explanatory view showing a second weaving operation in the consumable electrode type arc welding apparatus according to the present invention.

7 (a) and 7 (b) are explanatory views showing a wire supply position in the second weaving operation.

FIG. 8 is an explanatory view showing a multi-layer welding method according to the present invention.

FIG. 9 is an explanatory diagram showing lateral displacement of a filler wire with respect to a consumable electrode wire.

FIG. 10 is an explanatory diagram showing a conventional weaving operation.

FIG. 11 is an explanatory diagram showing a defect in a conventional weaving operation.

FIG. 12 is an explanatory diagram showing a defect in a conventional weaving operation.

[Explanation of symbols]

10 Welding robot 12 welding torch 14 Electrode wire feeder 15 Filler wire feeder 19 Welding power supply / control device 20 Filler control device 21 Robot controller 22 Input device 23 electrode wire delivery nozzle 24 Filler wire delivery nozzle Y1 Consumable electrode wire Y2 filler wire P1 Consumable electrode wire supply position P2 torch rotation center position P3 filler wire supply position B3 molten pool

Claims (9)

[Claims] 1. A consumable electrode wire supply unit for supplying a consumable electrode wire to a welding target through a welding torch; a filler wire supply unit for supplying a filler wire for a molten pool to be welded through the welding torch; The consumable electrode wire oscillates to the left and right with respect to the welding center line, and the welding torch is shaken with respect to the welding target so that the horizontal swing width of the filler wire is smaller than the horizontal swing width of the consumable electrode wire. A consumable electrode type arc welding device, comprising: a swinging motion means for moving the product. 2. The consumable electrode type arc welding apparatus according to claim 1, wherein the oscillating movement means causes the consumable electrode wire and the filler wire to oscillate both left and right with respect to a welding center line. The welding torch is rotated so that the rotation angle of the welding torch centering on the side behind the consumable electrode wire in the welding proceeding direction increases as the consumption electrode wire moves away from the welding center line. Consumable electrode type arc welding equipment. 3. The consumable electrode type arc welding apparatus according to claim 1, wherein the oscillating motion means keeps the rotation center on the welding center line with the lag side in the welding advancing direction as the rotation center from the consumable electrode wire. A consumable electrode type arc welding device, wherein the welding torch is rotated to swing the consumable electrode wire left and right with respect to the welding center line. 4. The consumable electrode type arc welding apparatus according to claim 1, wherein at least the welding speed, the welding current, the welding voltage, the torch angle, and the consumable electrode wire are left and right with respect to the welding center line. A parameter input section for inputting a movement width and a movement frequency for oscillating movement to both sides, and a control means for controlling the operation of the welding torch including the operation by the oscillating movement means based on the parameter input by the parameter input section. A consumable electrode type arc welding apparatus, further comprising: 5. A consumable electrode wire supply unit for supplying a consumable electrode wire to a welding target via a welding torch, and a filler wire supply unit for supplying a filler wire to a molten pool to be welded via the welding torch. In the welding method using the consumable electrode type arc welding device, the consumable electrode wire swings to the left and right sides with respect to the welding center line, and the lateral swing width of the filler wire becomes smaller than the lateral swing width of the consumable electrode wire. A consumable electrode type arc welding method, characterized in that the welding torch is oscillated with respect to the object to be welded. 6. The consumable electrode type arc welding method according to claim 5, wherein both the consumable electrode wire and the filler wire are oscillated to the left and right sides with respect to the welding center line, and the consumable electrode wire is The consumable electrode type arc is characterized in that the welding torch is rotated so that the rotational angle of the welding torch centering on the side lagging the welding advancing direction from the consumable electrode wire increases as the distance from the welding center line increases. Welding method. 7. The consumable electrode type arc welding method according to claim 5, wherein the welding torch is rotated while keeping the rotation center on the welding center line, with the side behind the consumable electrode wire in the welding proceeding direction being the rotation center. A consumable electrode type arc welding method, characterized in that the consumable electrode wire is moved to swing left and right with respect to a welding center line. 8. A multi-layer welding method using a consumable electrode type arc welding apparatus, wherein the lower layer is welded by the consumable electrode type arc welding method according to claim 7, and the upper layer is welded. A welding method characterized by being performed by an arc welding method. 9. The arc welding condition determining device used in the consumable electrode type arc welding device according to claim 1, wherein at least a welding speed, a welding current, a welding voltage, a torch angle, and the consumable electrode. An input unit for inputting a moving width and a moving frequency at which the wire swings left and right with respect to the welding center line, and a swing angle of the welding torch by the swing motion means is calculated based on the input values. An arc welding condition determining device, comprising: