JP2004223584A - Welding device and welding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a welding device and welding method which can secure an excellent welding quality with a superb penetration bead, even in the case of a butt weld joining with a misaligned root gap. <P>SOLUTION: The welding device to apply arc welding on the butt welding joint 8 with the root gap is equipped with a manipulator 1 to move a welding torch 2 inserted with a electrode wire 3 weaving along the welding line, and a control unit 10 which sets up the weaving width of the welding torch 2 based on the root gap and the misalignment amount of the butt welding joint 8 so that an arc 20 generated from the tip of the electrode wire 3 can reach both root edges of the butt welding joints 8, and controls the manipulator 1 according to the set-up value. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a welding device and a welding method for welding a butt joint having a root gap.
[0002]
[Prior art]
When welding a butt joint having a root gap, it is common to apply a backing material to the root gap part and pour molten metal into the groove in this state. In addition, the number of steps for attaching the backing material increases, and when a steel backing material is used, the joint efficiency may decrease. Further, in a box-shaped structure, it is often difficult to remove the backing material after welding. Therefore, even if a root gap is generated in the butt joint, the molten metal is bridged between the two facing base materials constituting the butt joint by weaving the electrode wire in the welding line direction, and a backing material is used. A technique for welding a butt joint without forming a back bead has been already proposed (for example, see Non-Patent Document 1).
[0003]
[Non-patent document 1]
Hikaru Yamamoto, et al., “Feedback control of back bead against root gap fluctuation in backingless V groove joint”, Transactions of the Japan Welding Society, November 2002, Vol. 20, No. 4, p. 499-505.
[0004]
[Problems to be solved by the invention]
The weaving width of the electrode wire is usually set to about the width of the root gap. Generally, the weaving center position of the electrode wire is adjusted to the center of the root gap so that the values of the voltage and current for both base materials during weaving are substantially equal (that is, the arc lengths for both joints are substantially equal). .
[0005]
However, when the heights of the two base materials constituting the butt joint are different (when the two base materials constituting the butt joint are different), the weaving is adjusted based on the adjustment of the weaving center position. The center and the center of the gap are shifted. Further, as described above, since the weaving width is set to about the width of the root gap, the distance from the tip of the electrode wire to the root edge is widened in the base material located relatively below. For this reason, in some cases, a problem may occur that the molten metal does not adhere to the vicinity of the root edge and a good back bead cannot be obtained.
[0006]
The present invention has been made in view of the above circumstances, and its object is to obtain a good back bead while ensuring a high welding quality even for a butt joint having a misplaced root gap. It is an object of the present invention to provide a welding apparatus and a welding method that can be used.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a first invention is a welding device for arc welding a butt joint having a root gap, wherein a manipulator for moving a welding torch having an electrode wire inserted therein while weaving the welding torch with respect to a welding line, The weaving width of the welding torch is set based on the root gap of the butt joint and the amount of misalignment so that the arc generated from the tip of the electrode wire can reach the root edges of both base materials constituting the butt joint. And a control device for controlling the manipulator according to the setting.
[0008]
If the weaving width is set to about the root gap, as in the conventional case, if there is a misalignment between the base materials, the distance from the root edge of one of the base materials to the tip of the electrode wire will increase and the arc will not reach. Therefore, the molten metal may not adhere to the vicinity of one of the root edges, and a good back bead may not be formed. On the other hand, in the present invention, in such a case, the weaving width, which is conventionally set to about the root gap, is adjusted (narrowed) in consideration of the amount of misalignment, so that the root edge of both base materials is adjusted. , And the molten metal can be adhered. As a result, even when the molten metal is bridged without using a backing material in the root gap of the misaligned butt joint, the molten metal is reliably adhered to the vicinity of the root edge of both base materials. Therefore, high-quality welding having a good back bead can be performed.
[0009]
According to a second aspect of the present invention, in a welding apparatus for arc welding a butt joint having a root gap, a manipulator for moving a welding torch having an electrode wire inserted thereto while weaving the welding wire, and supplying power to the electrode wire Power supply device, a wire feeding device for feeding the electrode wire to the welding torch, and an arc generated from the tip of the electrode wire can reach the root edges of both of the two base materials forming the butt joint. A welding device that sets welding conditions including a weaving width of the welding torch based on a root gap and a misalignment amount of the butt joint, and controls the manipulator, the wire feeder, and a power supply device according to the set conditions. It is characterized by having.
[0010]
According to a third aspect of the present invention, there is provided a welding apparatus for arc welding a butt joint having a root gap, wherein a manipulator movably gripping a welding torch through which an electrode wire is inserted while weaving the welding wire with the welding wire; A power supply device for supplying power, a wire feeding device for feeding the electrode wire to the welding torch at a speed according to the power supplied from the power supply device, and a root gap and a misalignment amount of the butt joint are input. A first procedure for setting, based on the input values of the first procedure, a weaving width and a moving speed of the welding torch, an electric power and a feeding speed of the electrode wire, and the manipulator and the welding manipulator and the welding speed are set according to the set welding conditions. The second step is to output a command signal to the power supply device. The electric power is supplied so that the length of the arc generated from the electrode wire becomes substantially constant. A third procedure for calculating the correction amount of the wire feeding speed, a fourth procedure for calculating the correction amount of the welding torch to the proper position of the weaving center position, and the respective correction amounts calculated in the third and fourth. A fifth procedure of outputting a command signal corrected based on the above to the power supply device and the manipulator, and a sixth procedure of repeatedly executing the first to fifth procedures at set intervals can be executed. A control device storing the program.
[0011]
In a fourth aspect based on the first to third aspects, the program for executing a switchback operation for forming a welding bead while repeatedly moving the welding torch in the welding line direction with respect to the manipulator. The apparatus is further stored in the apparatus.
[0012]
According to a fifth aspect of the present invention, in the first to fourth aspects, a root gap and an amount of misalignment between the two base materials constituting the butt joint are provided at a position near the welding torch in the manipulator. And a gap detecting means for outputting to the control device.
[0013]
According to a sixth aspect of the present invention, in the welding method for arc welding a butt joint having a root gap, when a misalignment occurs between two base materials constituting the butt joint, an arc generated from a tip of the electrode wire is generated. The weaving width of the electrode wire is narrowed relative to the root gap of the butt joint according to the amount of misalignment so that the root edges of both the two base materials can be reached.
[0014]
According to a seventh aspect of the present invention, in the welding method for arc welding a butt joint having a root gap, a weaving width, a moving speed, a supply power, and a power supply of the electrode wire are determined based on a root gap and a misalignment amount of the butt joint. A first procedure for setting the speed, a second procedure for correcting the feed speed of the electrode wire so that the length of the arc generated from the electrode wire is substantially constant, and a weaving center position of the electrode wire. And a third procedure for correction.
[0015]
An eighth invention is characterized in that, in the sixth or seventh invention, a switchback operation of forming a weld bead while repeatedly moving the electrode wire in the welding line direction is performed.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a welding device and a welding method of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of the welding apparatus of the present invention. In FIG. 1, 1 is a manipulator (welding robot) having an articulated arm 1a, 2 is a welding torch provided at the tip of the arm 1a, and the manipulator 1 is operated while weaving in a direction substantially orthogonal to a welding line. , The welding torch 2 can be moved. Reference numeral 3 denotes an electrode wire inserted into the welding torch 2, 4 denotes a tube for guiding the electrode wire 3 to the welding torch 2, and 5 denotes a wire feeding device for sequentially feeding the electrode wire 3 wound on a reel 6 to the welding torch 2. It is. Although not shown, the welding torch 2 is provided with a gas nozzle for injecting a shielding gas.
[0017]
Reference numeral 7 denotes a power supply for supplying electric power (current / voltage) to the electrode wires 3 and the like. The positive terminal 7a of the power supply 7 is connected to the electrode wire 3 (strictly, the tube 4), and the negative terminal 7b is a butt joint to be welded. Each is connected to a joint 8. An output terminal (not shown) of the power supply device 7 is connected to the wire feeding device 5, and the magnitude of a command signal (power) supplied from the power supply device 7 to the wire feeding device 5 causes the electrode wire 3 to rotate. The feed speed is adjusted.
[0018]
Reference numeral 9 denotes a robot control panel. The robot control panel 9 controls the manipulator 1 and the power supply device 7 to calculate a command signal. The command signal calculated by the control device 10 is transmitted to the manipulator 1 and the power supply device 7. A robot driver 11 and a power supply driver 12 for outputting data are built in. A gap sensor 13 detects a route gap or misalignment between the butt joints 8 and outputs the detected gap to the control device 10. The gap sensor 13 is located near the welding torch 2 at the tip of the arm 1a of the manipulator 1 (arrow in FIG. 1). Is provided on the front side in the welding line direction shown in FIG. As the gap sensor 13, for example, a known laser sensor or ultrasonic sensor is used.
[0019]
With such a configuration, when the welding start point and the end point are input to the control device 10, the welding device of FIG. Based on the above, the welding conditions are sequentially updated, and the manipulator 1 and the power supply 7 are controlled (the control flow by the control device 10 will be described later).
[0020]
When the manipulator 1 receives a command signal from the control device 10 output via the robot driver 11, the manipulator 1 performs welding while weaving the welding torch 2 with a weaving width and a moving speed (welding speed) according to the command signal. The arm 1a is operated so as to move in the direction of the arrow in the figure along the line.
[0021]
On the other hand, at the same time, when the power supply device 7 receives a command signal output from the control device 10 via the power supply driver 12, the power supply device 7 applies a voltage / current according to the command value to the electrode wire 3. The current applied to the electrode wire 3 flows in the order of the positive terminal 7a of the power supply 7 → the electrode wire 3 → the butt joint 8 → the negative terminal 7b of the power supply 7. As a result, an arc 20 is generated between the tip of the electrode wire 3 and the welding point of the butt joint 8, and the arc heat causes the tip of the electrode wire 3 and the welding point of the butt joint 8 to melt. Molten metal is formed on the surface. Further, with the consumption (melting) of the electrode wire 3, the power supply device 7 outputs a wire feed signal (voltage) of a magnitude corresponding to the command signal from the control device 10 to the wire feed device 5, By controlling the driving speed of the feeding device 5, the electrode wires 3 are sequentially fed to the welding torch 2.
[0022]
Next, a control procedure by the control device 10 will be described with reference to FIGS.
First, a control concept of an embodiment of a welding device and a welding method according to the present invention will be described with reference to FIG.
Generally, when weaving a butt joint having a root gap, the weaving width of the electrode wire is generally set to about the width of the root gap. Usually, when weaving welding is performed, the weaving center position of the electrode wire 3 is controlled in the weaving width direction such that the integrated values of the measured values of the current and the voltage on both sides of the weaving center are equal to each other. .
[0023]
Based on this, first, as shown in FIG. ₀ (Set the gap center position to O ₁ Assume that the two base materials 8a and 8b forming the butt joints that face each other through the base material 8a and 8b have substantially the same height (a case where there is no difference between the base materials 8a and 8b). In this case, the weaving width of the electrode wire 3 is set to the root gap W. ₀ By controlling the weaving center position as described above, the weaving center position becomes the gap center O ₁ And the arc length is kept at a constant value a, so that the distance from the arc center to the root edge is d ₀ (Hereinafter simply distance d ₀ Described). Here, the arc length a and the distance d ₀ Under such conditions, the molten metal adheres to the vicinity of the root edge, and the molten metal bridges between the root gaps without using a backing material, thereby forming a good back bead.
[0024]
On the other hand, as shown in FIG. 2B, the root gap W ₀ If there is a misalignment (misalignment amount M) between the base materials 8a and 8b having ₀ In the case where the arc length a with respect to the base materials 8a and 8b is maintained as described above, the appropriate weaving center position O2 after correction becomes the gap center O ₁ The root edge moves toward the base material 8a farther from the electrode wire 3 (relatively located below). In addition, this proper weaving center position O2 and gap center O ₁ Using the amount of misalignment M and the groove angle θ,
ΔO = (M / 2) × tan (θ / 2) (Equation 1)
Is required.
[0025]
Accordingly, on the base material 8a side, the distance from the arc center to the root edge is d. ₁ (Hereinafter simply distance d ₁ Described). Note that this distance d ₀ And distance d ₁ Δd (= d ₁ -D ₀ ) Is obtained by using the misalignment amount M and the groove angle θ.
Δd = M / {2 cos (θ / 2)} (Equation 2)
Is required.
[0026]
Therefore, in FIG. 2B, the distance d ₁ But distance d at which a good back bead was obtained ₀ As a result, the molten metal may adhere to only the vicinity of the root edge of the base material 8b to which the arc does not reach, and may not adhere to the vicinity of the root edge of the base material 8a to which the arc does not reach. That is, good back beads may not be obtained.
[0027]
Therefore, as shown in FIG. ₀ When the butt joints 8 (base materials 8a and 8b) having the misalignment amount M are targeted, the weaving width is changed according to the misalignment amount M as shown in FIG.
W ₁ = W ₀ −M × tan (θ / 2) (formula 3)
To change.
[0028]
Weaving width W after change ₁ Is the root gap W ₀ ΔW (= M × tan (θ / 2)). Thereby, the distance between the root edge of the base material 8a (distant from the tip of the electrode wire 3) and the center of the arc, which is relatively lower due to misalignment, is determined by the distance d that the arc (arc length a) can reach. ₀ Also, the electrode wire 3 can perform the weaving operation while maintaining the arc length a between itself and the other base material 8b.
[0029]
However, in the control concept according to the present embodiment described above, if the weaving width is changed from the state shown in FIG. 2B to the state shown in FIG. It is necessary to lower the tip position (closer to the base materials 8a and 8b side). This is performed, for example, by adjusting the height of the welding torch 2 or adjusting the feeding speed of the electrode wire 3. In the description of the control flow by the control device 10 described later, an example in which the latter feed speed adjustment of the electrode wire 3 is adopted will be described.
[0030]
FIG. 3 is a block diagram illustrating a schematic configuration of the control device 10. In FIG. 3, reference numeral 14 denotes an A / D converter which is a signal input portion. The A / D converter 14 supplies a detection signal from the gap sensor 13 and the signal to the electrode wire 3 by the power supply 7 through the A / D converter 14. The power (current / voltage) value is input to the control device 10 and converted into a digital signal. Reference numeral 15 denotes a read-only memory (ROM) for storing a program for a predetermined control procedure and constants necessary for control. The ROM 15 stores experimental data in advance for each combination of the root gap and the amount of misalignment of the butt joint 8. A welding condition table in which a combination pattern of welding conditions (applied power of electrode wire 3, feed speed, weaving width, welding speed) determined (or theoretically) is stored.
[0031]
Reference numeral 16 denotes a timer for measuring time, and 17 denotes a central processing unit (CPU) for calculating predetermined command signals for the manipulator 1 and the power supply 7 in accordance with welding conditions selected from a program stored in the ROM 15 and a welding condition table. is there. Reference numeral 18 denotes a random access memory (RAM) for temporarily storing the calculation result of the CPU 17 and numerical values during the calculation, and 19 converts a command signal calculated by the CPU 17 into an analog signal and converts the analog signal into a corresponding driver (the robot driver 11, the power supply This is a D / A converter that outputs to the driver 12).
[0032]
FIG. 4 is a flowchart of a control procedure based on a program stored in the control device 10. The control device 10 having the above configuration controls the manipulator 1, the wire feeding device 5, and the power supply device 7 based on the flow of FIG.
[0033]
In FIG. 4, first, in step 100, the control device 10 inputs a welding start point and an end point set by the operator from a setting unit (not shown) provided on the robot control panel 9 (or separately provided). The input welding start and end points are converted into digital signals via the A / D converter 14 and stored in the RAM 18.
[0034]
In step 101, a detection signal of the root gap and the amount of misalignment of the butt joint 8 from the gap sensor 13 is input via the A / D converter 14, converted into a digital signal and stored in the RAM 18, and the procedure proceeds to step 102. Transition.
[0035]
In step 102, the CPU 17 stores, in the ROM 15, appropriate welding conditions (applied power of the electrode wire 3, feed speed, weaving width, welding speed) for the root gap and the amount of misalignment input in step 101. One is selected (set) from the welding condition table and stored in the RAM 18. Then, a command signal for performing welding under the set welding conditions is calculated and output to the manipulator 1 and the power supply device 7 via the robot driver 11 and the power supply driver 12. The manipulator 1 is instructed on the moving speed (welding speed) and the weaving width of the welding torch 2, and the power supply device 7 is instructed on the feed speed and supply power (current / voltage) of the electrode wires 3.
At this time, the root wire and the misalignment of the butt joint 8 are adjusted so that the arc generated from the tip can reach the root edges of both the base materials 8a and 8b (see FIG. 2) constituting the butt joint 8. Weave with a weaving width calibrated smaller than the root gap for the volume.
[0036]
Subsequently, in step 103, during the weaving welding, the measured values of the current and voltage applied to the electrode wires 3 from the power supply device 7 are input, converted into digital signals via the A / D converter 14, and stored in the RAM 18, Move to step 104.
[0037]
In step 104, it is determined whether or not the current time by the timer 16 has reached the weaving cycle. If the determination is not satisfied, the process returns to step 103, and further inputs the measured values of current and voltage. If the current time has reached the weaving cycle and the determination in step 104 is satisfied, the procedure moves to step 105.
[0038]
In step 105, the voltage value for one cycle of weaving is integrated and stored in the RAM 18, and this value is compared with the integrated value of the voltage value for the immediately preceding cycle stored in the RAM 18 to correct the power control data. The amount is calculated and stored in the RAM 18. Specifically, if the integral value of the voltage is larger than the previous period, the wire feeding speed is increased in accordance with the difference so that the arc length is constant. In order to change the command value for the wire feeding device 5, the correction amount of the command signal to the power supply device 7 is calculated and stored.
[0039]
In Step 106, the measured values of the current and the voltage applied to the electrode wire 3 are measured on the left and right sides of the weaving (in FIG. 2, the base material 8a side and the base material 8b side with the weaving center as a boundary). Integrating and calculating a correction amount (distance) from the current weaving center position to an appropriate weaving center position so as to correct the deviation of these integrated values (that is, to make the arc length equal between the left and right weaving), To be stored.
[0040]
In the next step 107, when the time measured by the timer 16 reaches a predetermined period (1 / m times the weaving period, m: an integer), the CPU 17 calculates the correction amount based on the correction amounts calculated in steps 105 and 106. , A command signal for the manipulator 1 and the power supply device 7 is corrected, converted into an analog signal via the D / A converter 19, and output via the corresponding robot driver 11 and power supply driver 12, respectively. At this point, the weaving center position and the feeding speed of the electrode wire 3 are adjusted, and the state is controlled to the state shown in FIG.
[0041]
Subsequently, the process proceeds to step 108, where it is determined whether or not the current time by the timer 16 has reached a predetermined gap detection cycle (here, n times the weaving cycle, n: integer) by the gap sensor 13, and the determination is satisfied. If not, the procedure of steps 102 to 107 is executed again. If the current time has reached the gap detection cycle and the determination in step 108 is satisfied, the process proceeds to step 109.
[0042]
In step 109, it is determined whether or not the current position has reached the welding end point input in step 100. If the determination is not satisfied, the process returns to step 101, and the above steps 101 to 108 are repeated. That is, until the welding end point is reached, the welding conditions (applied power of electrode wire 3, feeding speed, weaving width, and the like) are determined based on the route gap and the amount of misalignment detection signals from gap sensor 13 for each gap detection cycle. , Welding speed), and the feedforward control of the manipulator 1 and the power supply 7 is repeated. Then, finally, when the welding end point is reached and the determination in step 109 is satisfied, the command signal to the manipulator 1 and the power supply device 7 is turned off, and the control procedure of FIG. 4 ends.
[0043]
As described above, according to the present embodiment, as described above with reference to FIG. 2C, when a misalignment occurs in the butt joint having a root gap, the electrode wire 3 conventionally set to about the root gap is used. Is adjusted in accordance with the misalignment amount (narrower than the root gap) so that the molten metal is securely attached to the root edges of both butted base materials. Then, based on such a concept, as described in FIG. 4, after the welding is started, the procedure of steps 101 to 107 is performed by a predetermined gap detection cycle (here, n times the weaving cycle, n: (Integer), and repeatedly executed until the welding end point input in step 100 is reached, so that even if the root gap or misalignment varies along the welding line due to the accuracy of the base materials 8a and 8b, The welding conditions including the appropriate weaving width according to the route gap and the misalignment are always selected and updated, and the manipulator 1 and the power supply 7 are appropriately operated and controlled.
[0044]
Therefore, according to the present embodiment, even when the molten metal is bridged without using the backing material in the root gap of the butt joint in which misalignment has occurred, both base materials constituting the butt joint are bridged. Since the molten metal can be reliably adhered to the vicinity of the root edge, high-quality welding having a good back bead can be performed.
[0045]
Although the case where the technical idea of the present invention is applied to mere weaving welding has been described above as an example, as shown in FIG. 5, in addition to weaving (see arrow 26 in the figure), a so-called switchback ( The present invention is also applicable to a case where the operation is performed in combination with the operation shown in FIG. The switchback referred to here is an operation in which the welding torch 2 is moved along the welding line while repeating an operation of forward → backward → forward as shown by an arrow 25 to superimpose a welding bead.
[0046]
This switchback operation is performed by, for example, moving the welding torch 2 to the ROM 15 (see FIG. 3) in the welding apparatus and the welding method described with reference to FIGS. This can be realized by storing a program for controlling the operation of the manipulator 1. The control procedure in the case of performing the welding in which the switchback operation is combined in this manner is substantially the same as that of FIG. 4 described above. However, in step 102, the stroke lengths of “forward” and “retreat” in the welding line direction are set. The combination pattern is incorporated in the above-mentioned welding condition table, and a command signal corresponding to the set stroke pattern (or a fixed value) is output to the manipulator 1 and the power supply device 7. Further, in this case, as the gap detection cycle in step 108, it is desirable that the operation of “forward → retreat → forward” in the welding line direction be one cycle, and the time required for this one cycle of operation be the gap detection cycle.
[0047]
In this manner, by applying the present invention to the weaving welding that performs the switchback operation, the same effect as described above can be obtained. The molten metal can be bridged to the root gap of the joint. Therefore, even when the root gap is relatively large, bridge welding can be easily performed with relatively low power, and even when misalignment occurs, a good back bead is formed with high welding quality. Can be secured.
[0048]
Also, an example has been described in which the detection data of the route gap and the misalignment are input to the control device 10 online by the gap detection sensor 13, but the present invention is not limited to this. May be input. Further, even if the processing accuracy and the butt accuracy of the butt joint are high and the root gap and misalignment are generated, if they are almost constant in the welding line direction, the step 108 in the control flow of FIG. Is also good. In steps 105 and 106, the feed rate of the electrode wire 3 and the correction amount of the weaving center are calculated, and in step 107, the corresponding command signal is corrected and output based on these correction amounts. In steps 105 and 106, the corresponding command signal may be corrected and output, and step 107 may be omitted. In these cases, similar effects can be obtained.
[0049]
Although the case where arc welding is performed only with the electrode wire 3 has been described as an example, the present invention is also applicable to, for example, a so-called double wire type welding device provided with a filler wire in addition to the electrode wire 3. Also, in FIG. 1, the wire feeder 5 is described as a so-called push type provided on the reel 6 side, but may be a so-called pull type provided on the welding torch 2 side or a combination thereof. Absent. In these cases, the same effect as above can be obtained.
[0050]
In the embodiment of the welding apparatus and the welding method according to the present invention described above, step 101 in FIG. 4 corresponds to the first step of inputting the root gap and the misalignment amount of the butt joint described in claim 3. Procedure ”. In step 102, the "weaving width and moving speed of the welding torch, the power and the feeding speed of the electrode wire, are set based on the input values of the first procedure," and the welding conditions thus set are set. , A step of outputting a command signal to the manipulator and the power supply device ”in step 105, wherein the step 105 is“ the feeding speed of the electrode wire such that the length of the arc generated from the electrode wire is substantially constant. The third procedure for calculating the correction amount of "." Step 106 corresponds to the “fourth procedure for calculating the correction amount of the weaving center position of the welding torch up to an appropriate position” described in the same paragraph, and step 107 corresponds to “the third and fourth calculations. Steps 108 and 109 correspond to “the fifth procedure for outputting a command signal corrected based on the respective corrected amounts to the power supply device and the manipulator”. Sixth procedure that is repeatedly executed for each cycle ”.
[0051]
In addition, the step 102 of FIG. 4 includes the step of setting the weaving width, the moving speed, the supply power, and the feed speed of the electrode wire based on the root gap and the amount of misalignment of the butt joint. Procedure ”. Step 105 also corresponds to “Second procedure for correcting the feeding speed of the electrode wire so that the length of the arc generated from the electrode wire becomes substantially constant” in the above item, and Step 106 is performed. , "A third procedure for correcting the weaving center position of the electrode wire".
[0052]
Further, the gap sensor 13 is provided at a position near the welding torch in the manipulator described in the claims, detects a root gap and an amount of misalignment between two base materials constituting the butt joint, Gap detecting means for outputting to the control device. "
[0053]
【The invention's effect】
Advantageous Effects of Invention According to the present invention, a butt joint having a root gap and a misalignment is targeted, and even when bridging a molten metal without using a backing material, a root edge of both base materials constituting the butt joint is provided. Since the molten metal can be reliably adhered to the vicinity, high-quality welding having a good back bead can be performed.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating an entire configuration of an embodiment of a welding apparatus according to the present invention.
FIG. 2 is an explanatory diagram of a control concept of an embodiment of a welding device and a welding method according to the present invention.
FIG. 3 is a block diagram illustrating a schematic configuration of a control device provided in an embodiment of the welding device of the present invention.
FIG. 4 is a flowchart of a control procedure according to a program stored in a control device provided in an embodiment of the welding device of the present invention.
FIG. 5 is an explanatory diagram for conceptually explaining the operation when the electrode wire is operated by a combination of weaving and switchback in the welding apparatus and the welding method of the present invention.
[Explanation of symbols]
1 Manipulator
2 Welding torch
3 electrode wire
5 Wire feeder
7 Power supply unit
8 Butt joints
8a, b base material
10 Control device
13 Gap sensor (gap detection means)

Claims (8)

In a welding apparatus for arc welding a butt joint having a root gap,
A manipulator that moves the welding torch through which the electrode wire is inserted while weaving the welding torch with respect to the welding line,
The weaving width of the welding torch is set based on the root gap of the butt joint and the amount of misalignment so that the arc generated from the tip of the electrode wire can reach the root edges of both base materials constituting the butt joint. And a control device for controlling the manipulator according to the setting. In a welding apparatus for arc welding a butt joint having a root gap,
A manipulator that moves the welding torch through which the electrode wire is inserted while weaving the welding torch with respect to the welding line,
A power supply for supplying power to the electrode wires,
A wire feeding device for feeding the electrode wire to the welding torch,
Including the weaving width of the welding torch based on the root gap and misalignment of the butt joint so that the arc generated from the tip of the electrode wire can reach the root edges of both the base materials forming the butt joint. A welding device, comprising: a welding device that sets welding conditions and controls the manipulator, the wire feeding device, and a power supply device according to the set conditions. In a welding apparatus for arc welding a butt joint having a root gap,
A manipulator that movably holds a welding torch through which an electrode wire is inserted while weaving the welding torch with respect to the welding line,
A power supply for supplying power to the electrode wires,
A wire feeder that feeds the electrode wire to the welding torch at a speed according to the power supplied from the power supply,
A first procedure for inputting the root gap and the amount of misalignment of the butt joint, and setting the weaving width and moving speed of the welding torch, the power and the feeding speed of the electrode wire based on the input values of the first procedure. Then, a second procedure for outputting a command signal to the manipulator and the power supply according to the set welding conditions, correction of the feeding speed of the electrode wire so that the length of the arc generated from the electrode wire becomes substantially constant. A third procedure for calculating the amount, a fourth procedure for calculating the correction amount of the weaving center position of the welding torch to an appropriate position, and a command signal corrected based on the correction amounts calculated in the third and fourth. A fifth procedure for outputting the same to the power supply device and the manipulator, and a sixth procedure for repeatedly executing the first to fifth procedures at set intervals. Welding apparatus is characterized in that a control device that stores grams. 4. The welding device according to claim 1, wherein the control device executes a program for causing the manipulator to execute a switchback operation of forming a welding bead while repeatedly moving the welding torch back and forth in a welding line direction. 5. A welding device, further stored. The welding apparatus according to any one of claims 1 to 4, wherein the welding apparatus is provided at a position near the welding torch in the manipulator, and detects a root gap and a misalignment amount between two base materials constituting the butt joint, A welding device comprising: a gap detection unit that outputs the signal to the control device. In a welding method for arc welding a butt joint having a root gap,
If a misalignment occurs between the two base materials constituting the butt joint, an arc generated from the tip of the electrode wire can reach the root edge of both the two base materials, in accordance with the amount of misalignment, A welding method, wherein a weaving width of an electrode wire is reduced with respect to a root gap of the butt joint. In a welding method for arc welding a butt joint having a root gap,
A first procedure for setting the weaving width, moving speed, supply power, and feed speed of the electrode wire based on the root gap and misalignment of the butt joint;
A second procedure of correcting the feed speed of the electrode wire so that the length of the arc generated from the electrode wire is substantially constant;
A third procedure for correcting the weaving center position of the electrode wire. 8. The welding method according to claim 6, further comprising performing a switchback operation of forming a welding bead while repeatedly moving the electrode wire in the welding line direction.

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