JP2002028784A - Method and equipment for consumable electrode type arc welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent defective welding caused by the melted balance of a filler wire in consumable electrode type arc welding using two wires, that is, a consumable electrode wire and a filler wire. SOLUTION: In an arc welding method using an electrode wire 4 generating an arc by a welding current applied between the electrode wire 4 and an object 1 to be welded, melting the object 1 and forming a molten pool 8 and a filler wire 3 which is heated by a current applied between the filler wire 3 and the object 1 to be welded and which is supplied to the above molten pool 8, by detecting either one out of a feeding speed, feeding resistance and vibrations of the above filler wire 3 and based on its detected result, the feeding speed of the filler wire 3 or a current value to be applied to the filler wire is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to two weldings of an electrode wire for generating an arc between a workpiece and a filler wire to be supplied to a molten pool without generating an arc between the workpiece and the workpiece. The present invention relates to a consumable electrode type arc welding method and apparatus using a wire.

[0002]

2. Description of the Related Art As a welding method using two welding wires, for example, a consumable electrode type arc welding method disclosed in Japanese Patent Application Laid-Open No. 3-275280 has been proposed.

In this consumable electrode type arc welding method, two wires are inserted into a shield nozzle, an arc is generated by the consumable electrode wire, a filler wire is inserted into a molten pool, and welding is performed from the consumable electrode wire to a base material. A part of the current is diverted and guided to the filler wire so as to be joined to the ground end of the welding power source.

[0004] By adopting such a welding method, in the welding of carbon steel, alloy steel, aluminum and the like,
Welding speed can be increased and welding can be performed at high speed, high efficiency and good workability. Further, by inserting the filler wire into the molten pool, it is possible to suppress the temperature of the molten pool, suppress the puckering phenomenon, and reduce the susceptibility to solidification cracking.

[0005]

As described above, in the consumable electrode type arc welding using two wires, a consumable electrode wire and a filler wire, the filler wire inserted into the molten pool is usually based on the heat of the molten pool. The welding conditions are set so that all are melted.

However, when the welding current applied to the consumable electrode wire decreases due to the influence of disturbance, the feed speed of the filler wire becomes excessive, or the current applied for preheating the filler wire decreases. As shown in FIG. 3, a part of the filler wire 3 may be left behind in the weld metal 2 joining the base material 1 to cause welding defects.
Also, the reaction force of the filler wire 3 hitting the bottom of the molten pool,
In some cases, the welding torch or the current-carrying tip is pushed up to make it difficult to continue welding work.

[0007] In addition, a consumable electrode wire and a filler wire are used.
In the consumable electrode type arc welding using this wire, the mechanism of the welding torch becomes complicated, so that not only the welding torch becomes large but also its weight becomes heavy. In addition, since the direction of the welding operation is limited by the arrangement of the consumable electrode wire and the filler wire in the welding torch, welding is often performed by an automatic welding device using a robot or the like. The defect cannot be found, and the location where the welding defect occurs may be enlarged.

In view of the above-mentioned circumstances, an object of the present invention is to provide a consumable electrode type arc welding system using two wires, a consumable electrode wire and a filler wire, to automatically detect the molten state of the filler wire and to prevent the filler wire from remaining. It is an object of the present invention to provide a consumable electrode type arc welding method and apparatus for preventing occurrence of welding defects due to welding.

[0009]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 of the present application generates an arc by a welding current applied to a workpiece and melts the arc.
In an arc welding method using an electrode wire forming a weld pool and a filler wire heated by an electric current applied between a workpiece and a weld wire, the feed speed and the feed resistance of the filler wire are provided. One of the vibration and the vibration is detected, and the feed speed of the filler wire or the current value applied to the filler wire is controlled based on the detection result.

According to a second aspect of the present invention, there is provided a welding torch having two current-carrying tips, an electrode wire feeding device for feeding an electrode wire, a workpiece to be welded, and the one current-carrying tip. A welding power source for applying a welding current between the electrode wires, a filler wire feeding device for feeding the filler wire, and a heating source for applying a heating current between the filler wire via the workpiece and the other conductive tip; A power supply, a detecting means disposed between a feed port of the filler wire feeding device and an insertion port of the welding torch, and detecting any of the feed speed, feed resistance, and vibration of the filler wire as a characteristic value; And a characteristic value detected by the detection means and a preset reference value. Based on the comparison result, the feed speed of the filler wire or the current value applied to the filler wire is controlled. And control means for providing.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a consumable electrode type arc welding apparatus showing a first embodiment of the present invention.

1 is a welding base material. 2 is a deposited metal. 3 is a filler wire. Reference numeral 4 denotes an electrode wire which is fed by a feeding device 5. Reference numeral 6 denotes a welding power source device, which includes a welding base material 1 and
And an arc is generated between the electrode wire 4 and the welding base material 1 to form a molten pool 8 on the welding base material 1 side.

A feeder 9 feeds the filler wire 3 toward the molten pool 8. Reference numeral 10 denotes a preheating power supply device, which is connected to the filler wire 3 via the welding base material 1 and the conducting tip 11, and supplies power for preheating to the filler wire 3.

A detector 12 detects the feed resistance of the filler wire 3. A setter 13 sets a reference value of the feed resistance. Reference numeral 14 denotes a comparison / determination unit that compares the output of the detector 12 with a reference value set in the setting unit 13 to determine whether there is an abnormality. Reference numeral 15 denotes a controller, which controls the feeding device 9 based on the comparison result of the comparison / determination unit 14.

With such a configuration, a welding current is applied between the welding base material 1 and the electrode wire 4 from the welding power supply 6 to generate an arc, thereby melting the welding base material 1 and the tip of the electrode wire 4. And the droplets are transferred to the welding base material 1 side to perform welding. At this time, the molten pool 8 is formed by the molten welding base material 1 and the droplet transferred from the electrode wire 4.

At the same time, the preheating power
A current for preheating is applied between the filler wire 3 and the filler wire 3 and the feeder 9 is operated to feed the filler wire 3 into the molten pool 8. The filler wire 3 is heated by Joule heat by the applied current, is melted by the heat in the molten pool 8, and mixes with the welding base material 1 and the electrode wire 3.

During the welding operation, the welding current applied to the consumable electrode wire decreases due to the influence of disturbance, the feed speed of the filler wire becomes excessive, or the current applied for preheating the filler wire is reduced. When the temperature is lowered, the filler wire 3 is not completely melted in the molten pool 8, and its tip abuts on the welding base material 1. Then, the feeding resistance of the filler wire 3 increases.

At the same time as the start of welding, the detector 12 detects the feed resistance of the filler wire 3 in the feeder 9 and sends the result to the comparator 14. The comparison / determination unit 14 compares the reference value set in the setting unit 13 with the measurement value sent from the detector 12, and when the detected feed resistance of the filler wire 3 becomes larger than the reference value, an abnormality is detected. Is determined to have occurred, and the determination result is sent to the controller 15.

When the feed resistance becomes larger than the reference value, the controller 15 controls the feed device 9 to reduce the feed speed of the filler wire 3 and to feed the filler wire 3 to the molten pool 8.
And the filler wire 3 is reliably melted.

When an automatic welding machine is used, the controller 1 is controlled in accordance with the control of the feed amount of the filler wire 3.
By controlling the moving speed of the welding torch 11 based on the output of No. 5, stable welding can be performed.

Further, instead of controlling the feeding device 9, the current for preheating applied to the filler wire 3 may be increased or decreased, or the feeding speed of the filler wire 3 and the applied current may be reduced. You may make it control simultaneously.

The feed resistance of the filler wire 3 can be detected, for example, as a current value required for feeding the filler wire 3 at a constant speed.

The feed speed may be detected and controlled instead of the feed resistance of the filler wire 3. The feed speed of the filler wire 3 can be easily obtained, for example, by detecting the number of rotations of the rollers of the feed device 9 per unit time.

In the setting device 13, a reference value corresponding to the characteristic detected by the detector 12 can be set.

FIG. 2 is a configuration diagram of a consumable electrode type arc welding apparatus showing a second embodiment of the present invention.

In FIG. 3, the same components as those in FIG. 1 are denoted by the same reference numerals. Reference numeral 16 denotes a measuring device that measures the vibration of the filler wire 3 sent from the feeding device 9. Measuring instrument 1
The measured vibration measured in 6 is sent to the detector 12,
The detector 12 detects, for example, the maximum amplitude within the sampling time and sends it to the comparison / determination unit 14.

On the other hand, in the setting unit 13, an allowable amplitude is set as a reference value. The comparator 14 compares the reference value with the detected value and sends the result to the controller 15.
The controller 15 controls one or both of the feed speed of the filler wire 3 and the current applied to the filler wire 3 as in the first embodiment.

Whether the feed speed of the filler wire 3 or the current applied to the filler wire 3 is controlled depends on the quality required for the workpiece. When the heat input amount is limited in the welded portion, the feed speed of the filler wire is adjusted, and when the welding amount or the leg length needs to be maintained, the amount of current applied to the filler wire is adjusted.

In each of the above embodiments, the welding power supply device 6 and the power supply device 1 for applying a current to the filler wire are used.
Although 0 is displayed as a separate body, it may be configured integrally. Further, as in the prior art, a configuration may be employed in which the welding current applied to the electrode wire is diverted to the filler wire.

[0030]

As described above, according to the invention of the present application, one of the characteristics such as the feed speed, the feed resistance, and the vibration generated by the feed of the filler wire is detected, and the feed speed or the feed speed of the filler wire is detected. Since the current for preheating applied to the filler wire is controlled, the amount of heat input to the work to be welded is limited, or the welding amount or leg length is maintained. It is possible to prevent the filler wire from remaining welding defects.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a consumable electrode type arc welding apparatus according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a consumable electrode type arc welding apparatus according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of a weld.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... welding base material, 2 ... welding metal, 3 ... filler wire, 4 ...
Electrode wire, 5 ... feeding device 5, 6 ... welding power supply device, 7 ...
Current-carrying chip, 8: molten pool, 9: feeding device, 10: preheating power supply device, 11: current-carrying chip, 12: detector, 13: setting device, 14: comparison / determination device, 15: controller, 16: measuring device .

Claims (2)

[Claims] An arc is generated and melted by a welding current applied between a workpiece and an object to be welded, and is heated by a current applied between an electrode wire forming a molten pool and the workpiece to be welded. In an arc welding method using a filler wire supplied to a molten pool, one of the feed speed, the feed resistance and the vibration of the filler wire is detected, and based on the detection result, the feed speed of the filler wire is determined. Alternatively, a consumable electrode type arc welding method characterized by controlling a current value applied to a filler wire. 2. A welding torch having two current-carrying tips, an electrode wire feeding device for feeding an electrode wire, and applying a welding current between the workpiece and the electrode wire via the one current-carrying tip. A welding power source, a filler wire feeding device for feeding a filler wire, a heating power source for applying a heating current between the filler wire via the workpiece and the other conductive tip, and a filler wire feeding device. Detecting means that is disposed between a feed port and an insertion port of the welding torch and detects any of the feed speed, feed resistance, and vibration of the filler wire as a characteristic value, and is detected by the detecting means. Control means for comparing the characteristic value with a preset reference value and controlling a feed rate of the filler wire or a current value applied to the filler wire based on the comparison result. Consumable electrode type arc welding equipment.