JP2023164003A - Welding device, program, and welding method - Google Patents

Abstract

To provide a welding device or the like for welding and repairing corroded parts scattered in a pipe in accordance with corrosive shapes and positions.SOLUTION: This welding device comprises a control unit. The control unit reads a standard program defining welding conditions for a recess in a pipe, acquires coordinates of the recess to be welded, generates an execution program on the basis of the standard program and the coordinates, and executes welding for the recess by the generated execution program. Preferably, the welding device has a plurality of standard programs stored, and the control unit generates the execution program on the basis of one selected standard program and the coordinates.SELECTED DRAWING: Figure 1

Description

The present invention relates to a welding device, a program, and a welding method.

Several techniques have been proposed to assist welding. For example, a welding robot system has been proposed in which a worker can easily teach operations in a manufacturing factory (Patent Document 1).

Japanese Patent Application Publication No. 2019-150930

In piping for transporting oil, natural gas, etc. (hereinafter referred to as "inside the pipe"), various forms of corrosion occur at various locations due to metal oxidation, etc., impairing the piping's function. When repairing a pipe, a worker enters the pipe and performs overlay welding (hereinafter referred to as "welding repair") to cover the surface of the pipe with metal.

In harsh welding environments such as inside pipes, there is a need for welding repairs that are efficient and easy on the operator. However, the technique disclosed in Patent Document 1 is suitable for a fixed welding environment such as a manufacturing factory, and is difficult to introduce into a pipe. Therefore, the efficiency of welding repair inside the pipe depends on the proficiency level of the worker, and there have been problems in that the burden on the worker is not reduced.

In one aspect, it is an object of the present invention to provide a welding device and the like that can suitably perform welding repair of corroded spots scattered within a pipe.

A welding device according to one aspect is a welding device including a control unit, wherein the control unit reads a standard program that defines welding conditions for a recess in a pipe, acquires the coordinates of the recess to be welded, and executes the standard program and the welding device. An execution program is generated based on the coordinates, and welding to the recess is executed using the generated execution program.

In one aspect, it is possible to suitably perform welding repair of corroded locations scattered within the pipe.

FIG. 2 is a schematic diagram showing the appearance of a welding device. FIG. 2 is a block diagram showing a configuration example of a welding device. FIG. 2 is a block diagram showing a configuration example of a control device. It is an explanatory diagram showing an example of a task program. FIG. 2 is an explanatory diagram showing how a task program is converted into a standard program. It is an explanatory view showing a standard program according to the size and shape of a recessed part. FIG. 2 is an explanatory diagram showing an example of an execution program. It is a flowchart which shows an example of the processing procedure which a welding apparatus performs. FIG. 3 is an explanatory diagram showing an overview of Embodiment 2; 7 is a flowchart illustrating an example of a processing procedure executed by the welding apparatus according to the second embodiment. It is an explanatory view showing how automatic measurement of a recessed part is performed. FIG. 7 is an explanatory diagram showing how a recess is repaired by welding according to Embodiment 3; 12 is a flowchart illustrating an example of a processing procedure executed by the welding apparatus according to Embodiment 3.

(Embodiment 1)
In this embodiment, a welding apparatus for welding and repairing recesses (corroded parts) scattered in a pipe due to corrosion of the pipe will be described. FIG. 1 is a schematic diagram showing the appearance of a welding device 11. FIG. 2 is a block diagram showing a configuration example of the welding device 11.

As shown in FIGS. 1 and 2, the welding device 11 includes a welding machine 14 having a welding torch 12 and a robot arm 13, a sensor 16 that senses the inside of the pipe 15, and a welding machine 14 that grounds the welding machine 14 with respect to the pipe. a control device 17 that controls the welding torch 12, the robot arm 13, and the installation mechanism; a generator 18 that supplies power to the welding machine 14, the sensor 16, the grounding mechanism 20, and the control device 17; , a light source 21 for illuminating the inside of the pipe 15, a gas cylinder 22 storing shielding gas for supplying to the welding torch 12 of the welding machine 14, and a controller 23 for inputting commands to the control device 17. and one or more carts 24 placed thereon.

The piping 15 to be repaired is often made of carbon steel. The trolley 24 may be configured by one unit, or when configured by two or more, they may be connected to each other via a connecting portion.

The welding machine 14 is, for example, a semi-automatic welding machine (GMAW; CO ₂ , MAG (Metal Active Gas)) that operates semi-automatically under computer control and a part of which is a robot. The welding machine 14 is a gas shielded arc welding machine, and uses a welding method called Gas Metal Arc Welding. This welding method called Gas Metal Arc Welding includes CO ₂ welding or MAG welding.

The welding machine 14 can automatically perform welding within the pipe 15 according to a program stored in the control device 17. The welding machine 14 includes a welding torch 12 that includes a tangential wire that also serves as a welding rod and a gas nozzle outside the welding torch, and a robot arm 13 that supports the welding torch 12. The tangential wire constitutes the electrode during gas-shielded arc welding.

The welding machine 14 has a power supply circuit (not shown) that receives power from the generator 18 and supplies power to each part. Welding machine 14 has a ground wire 19 electrically connected to piping 15 . The welding machine 14 can repair the bottom of the pipe 15 by welding.

The grounding mechanism 20 is interposed in the middle of the grounding wire 19 connected to the welding machine 14. The grounding mechanism 20 includes, for example, a drum around which the ground wire 19 is wound, and a motor that rotates the drum. The motor is, for example, a servo motor.

For example, the grounding mechanism 20 rotates the motor in the forward or reverse direction under control from the control device 17 and rotates the drum in the forward or reverse direction, thereby bringing the tip of the grounding wire 19 into contact with the inner surface of the pipe 15. , the tip of the ground wire 19 can be separated from the inner surface of the pipe 15.

Note that the configuration of the grounding mechanism 20 is not limited to the above-mentioned configuration; for example, the tip of the grounding wire 19 may be pressed against the pipe 15 by a reciprocating mechanism such as a spindle.

The robot arm 13 is, for example, composed of an orthogonal three-axis moving robot (X-axis, Y-axis, and Z-axis moving table), but may be composed of other multi-jointed arm-shaped robots.

The sensor 16 is a visual sensor, and is composed of a general camera or video camera having an image pickup device (CCD (Charge Coupled Device) sensor or CMOS (Complementary Metal Oxide Semiconductor) sensor) and a lens, and can monitor the inside of the pipe 15. Alternatively, the sensor 16 may be a laser displacement sensor that can measure the distance to the recess and the height displacement of the recess and the surrounding unevenness using a laser beam. You can.

The sensor 16 configured as a laser displacement meter can obtain information as image information by three-dimensionally obtaining unevenness on the inner surface of the pipe 15 including the recessed portion. The image information acquired by the sensor 16 is sent to the control device 17 and stored in the storage device of the control device 17.

The sensor 16 may be configured with a camera that does not require a separate light source 21, such as a night vision camera. The sensor 16 may include a laser measuring device or other distance sensor capable of measuring the distance between the recess of the pipe 15 and the welding torch 12.

The control device 17 is composed of a general PC (personal computer), but may be composed of another one-chip microcomputer, an ASIC (Application Specific Integrated Circuit), another computer, or the like.

The control device 17 includes, for example, a CPU (Central Processing Unit), storage devices such as ROM (Read Only Memory), RAM (Random Access Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), and the like. and various driver ICs (Integrated Circuits) that are electrically connected to the CPU to drive the motor of the robot arm 13 and control the welding torch.

The storage device stores various control programs (control software) for controlling the robot arm 13 and welding torch 12 of the welding machine 14. The storage device also stores an image analysis program (image analysis software) that analyzes image information acquired by the sensor 16. The storage device can store image information sent from the sensor 16 at any time.

The controller 23 has a plurality of operation buttons 25 for the operator to input commands, and a button for displaying commands input by the operator through the operation buttons 25 and error messages from the control device 17. It has a display section 26.

The generator 18 is comprised of a general diesel engine generator. The trolley 24 is a general trolley 24 (trolley) made of a metal material. The trolley 24 has a motor and a gearbox, and is self-propelled by the motor that receives power from the generator 18 (power circuit of the welding machine 14) under the control of the control device 17. It may be possible to move forward and backward by human power.

The light source 21 can receive power from the generator 18 and illuminate the inside of the pipe 15 . The light source 21 is composed of, for example, an LED illumination, but may be composed of another light source lamp such as a halogen lamp. If the sensor 16 is a night vision camera, the light source 21 may be omitted.

The gas cylinder 22 stores shielding gas (CO ₂ gas or inert gas such as argon) inside, and receives operation from the welding machine 14 to adjust the amount of shielding gas and send it to the gas nozzle of the welding torch 12. Can supply shielding gas.

FIG. 3 is a block diagram showing an example of the configuration of the control device 17. As shown in FIG.

The control device 17 includes a control section 170, a memory 171, and a storage section 172. The control unit 170 is a computing device such as one or more CPUs, and executes various information processing related to the welding device 11. The memory 171 is a temporary storage area such as a RAM, and temporarily stores the execution program B. The storage unit 172 is a storage device such as a ROM, and stores a program P (program product) that causes the control unit 170 to execute processing and a plurality of standard programs A. Standard program A and execution program B will be described later.

Note that the control device 17 may include a reading section that reads the portable storage medium 17a, and may read the program P from the portable storage medium 17a. Further, the control device 17 may download the program P from another computer.

FIG. 4 is an explanatory diagram showing an example of a task program. An overview of this embodiment will be explained below.

In addition, in the following description, the traveling direction of the welding device 11 will be described as the X direction, the direction perpendicular to the traveling direction as the Y direction, and the depth direction as the Z direction (see FIG. 4). Also, an arbitrary point on the surface of the pipe is set as the origin.

The left side of FIG. 4 shows how the welding torch 12 performs welding repair on a semicircular recess while moving. As shown in FIG. 4, when performing welding repair on a recess, the welding torch starts from the center point of the recess (referred to as the repair starting point) P1 and moves through multiple movement points (referred to as the repair completion point) P2 to P4. Perform welding repairs. Finally, the welding torch moves to the retracted position P5 outside the recess, and the welding repair of the recess is completed.

When performing welding as described above, the welding device 11 performs welding repair by executing a program (hereinafter referred to as a "task program") conceptually illustrated on the right side of FIG. The task program defines welding conditions for the recess in the pipe. Specifically, various parameters such as the size (size and depth) and shape of the recess, position information and attitude angle of the welding torch 12, welding speed, welding current, and welding voltage are defined.

In the example on the right side of FIG. 4, "Prog" in the first line represents the program number. "P" in the second line indicates the coordinates (x1, y1, z1) of the center point P1 which is the repair starting point, the attitude angle of the welding torch at the starting point (α1, β1, γ1), and the welding speed 80 (cm/min). ) represents. "AS" in the third line represents a welding current of 24 (A) and a welding voltage of 120 (V). "L" in the 4th to 6th lines represents the coordinates, attitude angle, and welding speed of each moving point (repair completion point) P2 to P4. "AE" on the seventh line indicates completion of welding. Then, "P" on the 8th line represents the coordinates, attitude angle, and speed of the retreat position P5, and "End" on the 9th line represents the end of the process.

The welding device 11 performs welding repairs by executing such a task program. However, the corrosion of the piping varies in location and shape, and each parameter needs to be corrected for each recess. However, it is substantially difficult for an operator to repeatedly make corrections within a narrow pipe.

Therefore, in the present embodiment, this problem is solved by preparing a plurality of "standard programs" according to the shape of the recess, etc., and generating "execution programs" each time from the standard programs.

FIG. 5 is an explanatory diagram showing how a task program is converted into a standard program. FIG. 5 illustrates how the coordinates of each moving point P1 to P5 of the welding torch 12 defined in the task program are corrected according to the coordinates of the center point P1 of the recess. As shown in FIG. 5, in this embodiment, by subtracting the coordinate values (x1, y1, z1) of the center point P1 from the coordinate values of each moving point P1 to P5, each Convert (standardize) the absolute coordinates of the moving point to relative coordinates. In this embodiment, a program in which the coordinates of the moving point of the welding torch 12 defined in the task program are converted into relative coordinates is referred to as a "standard program."

The parameters stored in the standard program can be changed via the control device 17. After accepting the parameter change, the control device 17 stores a new standard program having the accepted changed parameters.

FIG. 6 is an explanatory diagram showing a standard program according to the size and shape of the recess. The left side of FIG. 6 conceptually illustrates various recesses when viewed in plan. As shown in FIG. 6, the recesses have various shapes, such as round, square, and diamond shapes. Furthermore, the sizes in the XY plane are different, and the depths in the Z direction are also different.

Therefore, in this embodiment, the recesses are classified into a plurality of patterns according to the size (size and depth) and shape, and a standard program for each pattern is prepared. Specifically, by conducting welding experiments on recesses of different sizes and shapes, a standard program for each pattern is prepared.

FIG. 7 is an explanatory diagram showing an example of an execution program. FIG. 7 illustrates how a task program to be actually executed (hereinafter referred to as an "execution program") is generated from a standard program.

For example, the operator operates the controller 23 to align the welding torch 12 with the center point Pa (xa, ya, za) of the recess. Note that the operator may move the welding torch 12 manually. Next, the operator visually confirms the size, shape, etc. of the recess. Then, the operator selects the standard program to be used by inputting the number of the standard program to be selected using the controller 23. Then, the welding device 11 enters automatic welding mode and automatically performs welding repair.

The welding device 11 generates an execution program based on the selected standard program and the coordinates of the center point Pa of the recess where the welding torch 12 is currently located. Specifically, the welding device 11 adds the coordinates (xa, ya, za) of the center point Pa of the recess to be welded to the relative coordinates of each moving point specified in the standard program, thereby executing the execution program. generate. The generated execution program is temporarily stored in the memory 171.

An example of an execution program is illustrated on the right side of FIG. As shown in FIG. 7, by adding the coordinates (xa, ya, za) of the center point Pa of the recess, it can be seen that a task program starting from the center point Pa is newly generated.

The welding device 11 executes the execution program and repairs the recess by welding. This completes welding at one location. When welding of one recessed portion is completed, the welding device 11 erases the generated execution program from the memory 171.

Thereafter, the worker performs welding repairs in the same manner. That is, the operator moves the welding torch 12 to the center point of a different recess, checks the size, shape, etc. of the recess, and selects the standard program. When the standard program is selected, the welding device 11 adds the coordinates of the center point of the recess to be welded to the relative coordinates of each moving point defined by the standard program, generates and executes an execution program. The generated execution program is sequentially deleted when welding is completed.

As described above, welding repair can be performed without modifying the parameters of the task program, and it is possible to improve work efficiency and reduce the burden on the operator.

FIG. 8 is a flowchart showing an example of a processing procedure executed by the welding device 11. Based on FIG. 8, the processing contents of the welding device 11 will be explained.

The control unit 170 of the control device 17 receives an operation input for moving the welding torch 12 to the center point of the recess (step S11). The control unit 170 acquires the position to which the welding torch 12 has moved as the coordinates of the center point of the recess to be welded.

The control unit 170 receives a selection input for selecting one from a plurality of standard programs prepared in advance (step S12). The standard program is a program that defines welding conditions for a recess in a pipe, and is a program that relativeizes the coordinates of each moving point of the welding torch 12 with the coordinates of the center point of the recess as the origin. Standard programs are prepared depending on the size (size, depth) and shape of the recess.

The control unit 170 generates an execution program based on the selected standard program and the coordinates of the center point of the recess to be welded (step S13). Specifically, the control unit 170 generates the execution program by adding the coordinates of the center point of the recess to the coordinates of each moving point defined in the standard program. The control unit 170 stores the generated execution program in the memory 171 (step S14). The control unit 170 executes welding repair of the recessed portion based on the generated execution program (step S15).

The control unit 170 erases the execution program generated in step S13 from the memory 171 (step S16). The control unit 170 ends the series of processing.

As described above, according to the first embodiment, it is possible to suitably carry out welding repair of the corroded spots scattered within the pipe.

(Embodiment 2)
In this embodiment, a mode will be described in which the amount of movement of the welding torch 12 is expanded or decreased depending on the size of the recess. Note that the same reference numerals are given to the same content as in the first embodiment, and the explanation thereof will be omitted.

FIG. 9 is an explanatory diagram showing an overview of the second embodiment. Similar to FIG. 7, FIG. 9 illustrates how an execution program is generated. An overview of this embodiment will be explained based on FIG. 9.

In this embodiment, the welding device 11 specifies an enlargement rate or reduction rate (hereinafter, the enlargement rate and reduction rate are collectively referred to as "magnification rate") of the movement amount of the welding torch 12 after accepting the selection of the standard program. Receives specified input from the worker. Even if the shape of the recess is the same as the welding conditions specified in the standard program, the size may be different. In order to cope with this, this embodiment accepts the designation of the magnification. Specifically, the welding device 11 receives input of magnifications S _x , S _y , and S _z in each direction in the X direction, Y direction, and Z direction in the figure.

The welding device 11 generates an execution program based on the coordinates of the recess, the selected standard program, and the specified magnification. Specifically, as shown in FIG. 9, the welding device 11 multiplies the relative coordinates of each moving point specified in the standard task by specified magnifications S _x , S _y , and S _z . Then, the welding device 11 adds the coordinates of the center point of the recess to be welded. Thereby, even if the size of the recess is different from that of the standard program, it is possible to suitably handle the case.

FIG. 10 is a flowchart illustrating an example of a processing procedure executed by the welding apparatus 11 according to the second embodiment. After selecting the standard program (step S12), the control unit 170 of the control device 17 executes the following process.

The control unit 170 receives a designation input that designates an enlargement rate or a reduction rate of the movement amount of the welding torch 12 (step S201). Specifically, the control unit 170 receives an input of an enlargement rate or a reduction rate in each of the X direction, Y direction, and Z direction. The control unit 170 generates an execution program based on the specified enlargement or reduction ratio, the coordinates of the center point of the recess to be welded, and the standard program selected in step S12 (step S202). Specifically, as described above, the control unit 170 multiplies the relative coordinates of each moving point defined in the standard program by the magnification specified in step S201, and further adds the coordinates of the center point of the recess. The control unit 170 moves the process to step S14.

As described above, according to the second embodiment, even if the size of the recess is different from the size specified by the standard program, this can be suitably handled.

(Embodiment 3)
In this embodiment, a mode will be described in which welding repair of a recessed portion is fully automated. Contents that overlap with those in Embodiments 1 and 2 will be designated by the same reference numerals and descriptions will be omitted.

FIG. 11 is an explanatory diagram showing how automatic measurement of recesses is performed. FIG. 11 illustrates how the sensor 16 senses the recess and measures the coordinates, size (size, depth), and shape of the center point of the recess.

The sensor 16 is a visual sensor as described above, and is a sensor capable of measuring the position, size, etc. of an object. In this embodiment, the welding device 11 automatically recognizes the recess from the sensor data from the sensor 16, and specifies the coordinates, size (size, depth), and shape of the center point of the recognized recess. Then, the welding device 11 automatically performs welding repair of the recessed portion based on the specified coordinates and the like.

FIG. 12 is an explanatory diagram showing how a recess is repaired by welding according to the third embodiment. For example, the welding device 11 automatically moves the welding torch 12 to the center point of the recess without depending on the operator's operation. The welding device 11 then selects a standard program from the shape of the recess identified above, regardless of the operator's selection. Further, the welding device 11 automatically specifies the magnification based on the size of the specified recess.

Welding device 11 generates an execution program based on these parameters. That is, the welding device 11 generates an execution program based on the coordinates of the center point of the recess identified above, the selected standard program, and the specified magnification. The welding device 11 repairs the concave portion by welding by executing the generated execution program. The welding device 11 repeats the same process thereafter, and automatically repairs other recesses by welding.

FIG. 13 is a flowchart illustrating an example of a processing procedure executed by the welding apparatus 11 according to the third embodiment.

The control unit 170 of the control device 17 acquires sensor data obtained by sensing the inside of the pipe from the sensor 16 (step S301). The sensor data is, for example, data related to a visual sensor, and is data that can specify the position, size, etc. of the recess. The control unit 170 recognizes the recess based on the sensor data (step S302). Then, the control unit 170 specifies the coordinates, size (size, depth), and shape of the center point of the recognized recess (step S303).

The control unit 170 moves the welding torch 12 to the coordinates of the center point of the recess identified in step S303 (step S304). Furthermore, the control unit 170 selects a standard program based on the shape of the recess identified in step S303 (step S305). Furthermore, the control unit 170 specifies the magnification of the amount of movement of the welding torch 12 based on the size of the recess identified in step S303 (step S306).

The control unit 170 generates an execution program based on the coordinates of the center point of the recess identified in step S303, the standard program selected in step S305, and the magnification specified in step S306 (step S307). The control unit 170 moves the process to step S14.

The welding device 11 repeats the above process to repair the recess by welding. For example, the welding device 11 repeatedly moves by one field of view that can be sensed (photographed) by the sensor 16, and each time it moves, it acquires sensor data at that location, generates an execution program, and performs welding repair of the recess.

As described above, according to the third embodiment, a series of processes can be automated and welding repair can be performed more suitably.

The embodiments disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is determined based on the claims, not the meaning disclosed above, and includes all changes within the meaning and scope equivalent to the claims.

Items described in each embodiment can be combined with each other. Moreover, the independent claims and dependent claims recited in the claims may be combined with each other in any and all combinations, regardless of the form in which they are cited. Further, although the scope of claims uses a format in which claims refer to two or more other claims (multi-claim format), the invention is not limited to this format. It may be written using a multi-claim format that cites at least one multi-claim.

11 welding device 12 welding torch 13 robot arm 14 welding machine 15 piping 16 sensor 17 control device 17a portable storage medium 170 control unit P program (program product)
A Standard program B Execution program 20 Grounding mechanism 21 Light source 22 Gas cylinder 23 Controller 24 Dolly 25 Operation button 26 Display section

Claims (12)

In a welding device including a control section,
The control unit includes:
Reads the standard program that specifies the welding conditions for the recess in the pipe,
Obtain the coordinates of the recess to be welded,
generating an execution program based on the standard program and the coordinates;
A welding device that executes welding to the recessed portion according to the generated execution program. Multiple standard programs are stored,
The welding apparatus according to claim 1, wherein the control unit generates an execution program based on the selected one standard program and the coordinates. Multiple standard programs are stored depending on the size and shape of the recess,
The control unit includes:
Select one standard program according to the size and shape of the recess to be welded,
The welding apparatus according to claim 2, wherein an execution program is generated based on the selected one standard program and the coordinates. The control unit includes:
Based on the sensor data obtained from the sensor that senses the inside of the pipe, the size and shape of the recess are identified,
The welding device according to claim 3, wherein a standard program is selected according to the size and shape of the specified recess. The control unit includes:
Based on sensor data obtained from sensors sensing inside the pipe, the coordinates, size and shape of multiple recesses are identified,
Select a standard program according to the size and shape of each identified recess,
The welding apparatus according to claim 3 or 4, wherein an execution program for each recess is generated based on the specified coordinates of the recess and the selected standard program. The welding apparatus according to claim 1, wherein the standard program is a program in which absolute coordinates of each movement point of the welding torch are converted into relative coordinates with the coordinates of the center point of the recess as the origin. The control unit includes:
The welding apparatus according to claim 6, wherein the relative coordinates of each moving point specified in the standard program are multiplied by an enlargement rate or a reduction rate according to the size of the recess. The control unit includes:
The welding apparatus according to claim 6, wherein the execution program is generated by adding the coordinates of the recess to be welded to the relative coordinates of each moving point defined in the standard program. The control unit includes:
Accepts changes to parameters that define pre-stored standard programs,
The welding apparatus according to claim 1, further comprising storing a new standard program having the received changed parameters. The control unit includes:
Store the generated execution program in the storage unit,
The welding device according to claim 1, wherein the execution program stored in the storage unit is erased after welding to the recess is completed. Reads the standard program that specifies the welding conditions for the recess in the pipe,
Obtain the coordinates of the recess to be welded,
A program that causes a computer to execute a process of generating an execution program based on the standard program and the coordinates. Reads the standard program that specifies the welding conditions for the recess in the pipe,
Obtain the coordinates of the recess to be welded,
generating an execution program based on the standard program and the coordinates;
A welding method in which welding to the recess is performed using the generated execution program.

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