JP2000061691A - Piping welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely execute welding of piping and removing of a residual stress by providing a first travelling head running on a circular arc rail arranged in parallel with a weld joint to be formed, a second travelling head running on a straight rail arranged on the first travelling head, and feeding mechanisms to respectively make the first and second travelling heads run and equipping the second travelling head with preheating, welding and cooling units. SOLUTION: A first travelling head 36 is made to turn around a center axis of pipings 11, 12 in a longitudinal direction and then a welding unit 54 is moved to the above of a groove 13 at a initial position. A first feeding mechanism 46 is operated to turn a welding torch along the groove 13, a welding wire driving mechanism and a welding power source are operated to execute normal welding by the welding unit 54, and at the same time the groove 13 and the area of its both sides are heated by a burner. A second feeding mechanism 51 is operated to shift a cooling unit 56 to the above of a welded bead, to turn around the pipings 11, 12, and then to cool the welded bead and its neighboring area. Thereby, only providing the piping 11, 12 with the welding equipment enables continuous welding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe welder, and more particularly to a welder suitable for welding and joining pipes in various plants.

[0002]

2. Description of the Related Art Conventionally, in welding and joining plant pipes, workers still directly perform work such as installation of jigs and welding, and further, improvement of residual stress is also made by the worker after welding. At present, it is done by hand such as cooling with water or attaching a jig having a small linear expansion coefficient to a pipe before welding.

[0003]

The welding of the piping for the plant is not only a difficult work itself, but also the work has a large diameter, and therefore must be welded at a high place.
In addition, equipment such as large and heavy jigs must be handled at high places, forcing the worker to perform dangerous work. Furthermore, since all the work is done by hand, not only the welding and residual stress removing work, but also the setup work of these is time-consuming and costly. Although a machine for performing welding and post-treatment is provided in Japanese Patent Laid-Open No. 6-182578, the equipment for performing the treatment must be replaced for each work, and the above-mentioned problems are sufficiently solved. Not resolved.

An object of the present invention is to provide a pipe welding machine which can safely and efficiently weld and join pipes and remove residual stress.

[0005]

In order to achieve the above object, the pipe welding machine of the present invention comprises an arc rail arranged parallel to a weld joint to be formed and a first arc traveling on the arc rail. A moving base, a linear rail that is arranged on the first moving base crossing the arc rail, a second moving base that travels on the linear rail, and a first moving base that causes the first moving base to perform the traveling. The feed mechanism, the second feed mechanism that causes the second moving table to perform the traveling, and the mechanism that guides toward the welding joint on the second moving table are attached to the second moving table. It has a preheating unit, a welding unit and a cooling unit.

In order to achieve the above-mentioned object, the pipe welding machine of the present invention includes a temporarily welded pipe, an arc rail arranged in parallel with a weld joint to be formed, and an arc rail on the arc rail. The first moving base that travels, the linear rail that is arranged on the first moving base crossing the arc rail, the second moving base that travels on the linear rail, and the traveling of the first moving base. The first feed mechanism to do, the second feed mechanism to make the traveling on the second moving table, and the third feeding mechanism to move toward the welded joint on the second moving table. A welding device equipped with a preheating unit, a temperature detection unit, a welding unit, a distance detection unit and a cooling unit attached to the second moving table, and a preheating operation of a portion for forming a welding joint in the preheating unit, in the temperature detection unit. Temperature measurement of the part After the preheating unit has been preheated to the set temperature based on the data from the temperature detection unit, the welding unit is made to weld, and then the cooling unit is made to rapidly cool the above-mentioned part, and the compression residual of the pipe remains. A controller for improving the stress, preventing stress corrosion cracking, and performing these operations by operating the feed mechanism and the guide mechanism based on the data from the distance detection unit.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a pipe welding machine of the present invention is
Hereinafter, description will be given with reference to the drawings.

This pipe welder is for welding and joining the temporarily welded plant pipes, and is equipped with a welding device installed on the outer surface of the pipes.

The piping is indicated by reference numeral 1 in FIGS. 1 to 6.
1, 12 are shown. These pipes 11, 1
Reference numeral 2 is made of a steel pipe having a groove 13 formed at its end, and is coaxially arranged with its central axes in the longitudinal direction aligned, and the groove 13 is temporarily welded.

As shown in FIGS. 1 to 4, the welding apparatus 10 includes a pair of arcuate rails 21, 21 arranged at intervals.
22 and a main body 23 that runs on these arc rails.

The arc rail 21 includes a base 24 and a support 2
5 and rail members 26 and 27. The base 24 is in the form of a wide ring. Support 2
Reference numeral 5 denotes a ring having a narrow width and the largest outer diameter, which is arranged at one end of the base 24 and fixed thereto. The rail member 26 is in the form of a ring having an outer diameter smaller than that of the support 25.
It is arranged at the other end of 4 and is fixed to this. The rail member 27 is in the form of a ring having an outer diameter smaller than that of the rail member 26, is arranged between the support 25 and the rail member 26, and is fixed to the base 24. The circular arc rail 22 includes a base 28, a support 29, and a rail member 31. The base 28 is in the form of a wide ring. The base itself consists of a magnet. The support 29 is in the form of a ring having the same outer diameter as the support 25, and is arranged at one end of the base 28 and fixed thereto. The rail member 31 is in the form of a ring having the same outer diameter as the rail member 27, and is arranged at the other end of the base 28 and fixed thereto.

Each of the arc rails 21 and 22 is provided with a pipe 11,
Twelve longitudinal center axes are divided at equal intervals. The segment of the arc rail 21 includes the base 24, the support 25, and part of the rail members 26 and 27, and the segment of the arc rail 22 includes the base 28 and the support 29.
And a part of the rail member 31 is included. These segments fit the protrusions 32 and the grooves 33 at the adjacent ends of the segments forming the bases 24 and 28 to each other, and together with the connecting plates 34 arranged on both side surfaces so as to straddle the mating surfaces of the adjacent segments. The circular rails 21 and 22 are formed by connecting with the through bolt 35.

The main body 23 is provided with moving bases 36 and 37. The moving base 36 engages the two grooves on one of the gate posts with the rail members 26 and 27, and the one groove on the other gate post with the rail member 31 to support 25,
It is arranged between the rollers 29 and 29 and is supported by the supports 25 and 29 and the rail members 26 and 31 via the rollers 38 and 39 and the roller groups 41 and 42. Laura 3
As shown in FIG. 3, 8 are arranged at equal intervals with respect to the central axes of the pipes 11 and 12 in the longitudinal direction, and the shafts thereof are held by bearings in a support 25. The rollers 39 are also arranged at equal intervals with respect to the central axes of the pipes 11 and 12 in the longitudinal direction, and the shafts thereof are held by bearings in the support 25. The main body 23 is provided with arc grooves 43, 43a centered on the longitudinal center axes of the pipes 11, 12 on both side surfaces, and the roller 38 is engaged with the arc groove 43 and the roller 39 is engaged with the arc groove 43a. Further, the shafts of the respective rollers are attached to the arc rails 21 and 22 by passing through the openings on the side surfaces of the arc grooves 43 and 43a. The roller group 41, as well shown in FIG. 5, includes rollers that contact the peripheral surface of the rail member 27 and rollers that contact both side surfaces of the rail member 27. Each roller has a shaft held by a bearing on a carriage 36.
The roller group 42 also includes rollers that come into contact with the peripheral surface of the rail member 31 and rollers that come into contact with both side surfaces of the rail member 31, and each roller shaft is held by bearings on the moving base 36. Therefore, the moving table 36 is
Rail member 27 in 8, 39 and roller groups 41, 42
By the roller contacting the peripheral surface of the pipe 11, 12, the movement of the pipes 11, 12 in the direction orthogonal to the central axis of the longitudinal direction, that is, FIG.
The vertical movement of the roller group 41, 4 is restricted.
The movement of the pipes 11 and 12 along the central axis direction of the pipes 11 and 12 is restricted by the rollers contacting both side surfaces of the rail member 27 in 2 so that the pipes 11 and 12 do not separate from the arc rails 21 and 22.
A smooth turning can be performed around the central axis of the pipes 11 and 12 in the longitudinal direction.

A gear 44 is provided on the entire peripheral surface of the rail member 26.
Is provided. A pinion gear 45 is engaged with the ring gear 44. The pinion gear 45 has a shaft held by a bearing on the moving base 36. Motor 46
Is incorporated in the gate post portion of the moving base 36, and the motor shaft is coupled to the shaft of the pinion gear 45.

A straight rail 47 is laid between the gate columns of the moving table 36. Both ends of the linear rail 47 are fixed to each of the gate posts. The movable table 37 is held by a linear rail 47 via a slide bearing 48 incorporated in the upper member 48. These straight rails 4
A ball screw 49 is arranged between the seven. 1, there are two linear rails 47, and a ball screw 49 is arranged between the linear rails 47 in parallel with the linear rail 47, and both ends of the linear rail 47 are located at the gate pillar portion of the moving base 36. Held in. The motor 51 uses the moving table 36
, And the motor shaft is connected to the ball screw 49. Ball screw 4
The nut No. 9 is incorporated in the member 48 of the moving base 37.

The moving table 37 is in the form of a hollow box, and has a distance detecting unit 52 and a heating unit 5 inside.
3, a heating unit 53a, a welding unit 54, a temperature detection unit 55 and a cooling unit 56 are incorporated.

7 and 8 show details of the distance detection unit 52. The distance detection unit 52 includes a laser displacement meter and a feeding mechanism. Feed mechanism is base 6
1, a rail 63, a holding base 64, a ball screw 65, a motor 66 and the like. The base 61 is made of a member having a channel-shaped cross section, and has an opening 62 in the lower wall portion. The rail 63 is arranged between the upper and lower wall portions of the base 61, and both ends thereof are fixed to these wall portions. The holding base 64 is attached to the rail 63 via a slide bearing, and can be linearly moved along the rail 63 in the vertical direction in FIGS. 7 and 8. The ball screw 65 is provided on the base 61 in parallel with the rail 63.
And both ends are held by bearings on the upper and lower wall portions of the base 61. The nut of the ball screw 65 is the holder 6.
It is fixed at 4. The motor 66 is installed on the base 61, and the motor shaft is coupled to one end of the ball screw 65. This feeding mechanism is arranged inside the moving base 37 by aligning the opening 62 in the lower wall portion of the base 61 with the opening in the lower wall portion of the moving base 37, and also moves the base 61 into the moving base 37. It is fixed to the seat inside. The laser displacement meter is incorporated in the holding table 64, and the position where the tip projects outside the moving table 37 through the opening 62 in the base 61 and the opening in the moving table 37 by operating the motor 66. The movement to and from the position retracted inside 37 is possible.

The heating units 53, 53a are respectively provided with a feed mechanism having the same structure as the feed mechanism in the burner and the distance detection unit 52, and are supported by the moving table 37 via the feed mechanism. The burner is incorporated in a holding table included in each feeding mechanism, and by operating a motor in each feeding mechanism, the burner is passed through the opening 62 in the base 61 and the opening in the moving table 37 to the outside of the moving table 37. It is possible to move between a position protruding to the inside and a position retracted inside the movable table 37.

The welding unit 54 has the same feed mechanism as that of the welding torch and the distance detection unit 52. The welding torch is incorporated in a holding table included in the feed mechanism, and by operating a motor in the feed mechanism, the opening 62 whose tip is in the base 61 and the moving table 3 are provided.
It is possible to move between a position protruding to the outside of the movable table 37 and a position retracted inside the movable table 37 through the opening in 7. The welding torch is attached to the holding base of the feed mechanism via a mechanism having three joints, and can rotate about three axes orthogonal to each other. The rotation is performed by, for example, three motors incorporated between each of the rotary arms of the joint mechanism and the holding table.

The temperature detection unit 55 has the same feed mechanism as the feed mechanism in the temperature detector and the distance detection unit 52. The temperature detector is incorporated in a holding base of the feed mechanism, and by operating a motor in the feed mechanism, the opening 62 whose tip is in the base 61 and the movable base 3 are provided.
It is possible to move between a position protruding to the outside of the movable table 37 and a position retracted inside the movable table 37 through the opening in 7.

Among these units 52 to 55, the heating units 53 and 53a, as shown in FIG. 9, connect each burner 68 to one gas source 71 through one gas supplier 69.
It is connected to the. Ignition and gas flow rate adjustment are performed by the gas supply device 69. The welding torch 72 of the welding unit 54 is the driving mechanism 7 for the welding wire or welding line.
3 and a welding power source 74 for setting welding conditions such as welding current. The nozzles 76 of the heating units 53, 53a are
It is connected to a cooling fluid source 78 such as a gas compressor or a gas cylinder.

The welded joints of the pipes 11 and 12 are made by connecting the pipes 11 and 12.
Preheating the portion forming the weld joint including the groove 13 in 12, and then performing welding while preheating,
After that, it is done by quenching the weld joint forming portion. That is, the temperature of the welded joint forming portion is measured by the temperature detection unit 55 after preheating the welded joint forming portion by the heating units 53 and 53a, and when the set temperature is reached, the preheating is continued by the welding unit 54. Welding is performed, and thereafter, the surfaces of the pipes 11 and 12 near the welded joints are rapidly cooled by the cooling unit 56.

In this pipe welding machine, the series of operations are performed by the control device 100 controlling the welding device 10.

The control device 100 has an arithmetic unit, a control unit, a storage unit, etc., and as shown in FIG. 9, a motor 46 for causing the moving base 36 to turn around the central axis of the pipes 11, 12 in the longitudinal direction. Drive circuit 101 and encoder 102, the drive circuit 103 and encoder 104 of the motor 51 that causes the moving table 37 to perform linear movement along the longitudinal center axes of the pipes 11 and 12, and the laser displacement meter 67 of the distance detection unit 52. Motor 66 of feeding mechanism
Drive circuit 105 and encoder 106, the drive circuit 107 of the motor 66 in the feed mechanism of the heating units 53 and 53a, the encoder 108 and gas feeder 69 of each motor, and the motor and joint mechanism in the feed mechanism of the welding unit 54. Drive circuits 109 for the motors that move each of the rotary arms included in the encoder, encoders 110 for these motors, a temperature detector 75 in the temperature detection unit 55, and a drive circuit 11 for the motors in the feed mechanism.
1 and the encoder 112, the motor drive circuit 113 in the feed mechanism of the cooling unit 56, the encoder 114
Also, it is connected to the on-off valve 77, the welding line drive mechanism 73 and the welding power source 74, the motor 46 rotates the moving base 36, the motor 51 linearly moves the moving base 37, and the feeding of the units 52 to 55. The burner 68, the temperature detector 75, the welding torch 72 and the cooling nozzle 76 are positioned by operating the motor of the mechanism, and the respective units 52 to 55 are caused to perform work, so that the compressive residual stress is small and We are trying to obtain welded joints without corrosion cracking. explain in detail.

Arc rails 21 for the pipes 11, 12;
Installation of 22 will be described with reference to FIGS. 4 and 5.
On both sides of the groove 13 on the pipe surface, segments of the arc rail 21 are arranged around the pipes 11 and 12 with a certain distance or in parallel with the groove 13, and the projection 32 and the groove 33 of each segment are arranged. Are fitted together, the connecting plates 34 are arranged on both side surfaces so as to straddle the mating surfaces of the respective segments, and the connecting plates 34 and the segments are connected by the through bolts 35. Arc rail 2
The positioning of 1, 22 is performed by connecting the bases 24, 28 to the piping 11, 1
It is done by making it adsorb to 2. The attachment of the main body 23 to the circular arc rails 21 and 22 is performed by, for example,
Fit the two grooves in one of the gate columns of the moving base 36 to the rail members 26 and 27, fit one groove in the other gate column to the rail member 31, and fit the rollers 38 and 39 in the arc grooves 43 and 43a. Support the main body 23,
It is made by placing between 29. Body 23
Is placed on the arc rails 21 and 22, the roller 3
Support 2 via 8, 39 and roller groups 41, 42
5, 29 and rail members 26, 31.
Therefore, the main body 23 can swivel along the rail members 21 and 22 about the longitudinal center axes of the pipes 11 and 12.

In welding, the worker must detect the distance detection unit 52,
Heating units 53, 53a and temperature detection unit 55
It is started by setting welding conditions such as the distance between the surface of the pipes 11 and 12, the preheating temperature, the swivel angles of the welding unit 54 and the cooling unit 56, the number of welding layers, and the welding current.

When the operation of this welding machine is started, the controller 1
00 is the distance detection unit 52 according to the program.
To measure the shape of the groove 13. The measurement of the groove shape is started by the control device 100 activating the motors 46 and 51 of the welding device 10. In FIG. 5, when the motor 46 is operated, the gear 45 is rotated while being engaged with the ring gear 44, the movable base 36 is swiveled around the longitudinal center axes of the pipes 11 and 12, and when the motor 51 is operated, the screw is rotated. The shaft 47 rotates, the movable table 37 moves the pipe 11,
The distance detection unit 52 is moved above the groove 13 by linearly moving parallel to the central axis of the longitudinal direction 12. After that, the control device 100 controls the distance measuring unit 52 shown in FIGS.
Of the feed screw 65 by operating the motor 66 in the feed mechanism of
Is rotated, and the holder 64 is connected to the pipes 11, 1 until the distance between the tip of the laser displacement meter 67 and the groove 13 becomes a predetermined distance.
2 toward the surface (step S in FIG. 10).
1). When the laser displacement meter 67 is positioned in this way, the control device 100 operates the motor 51 shown in FIG. 5, rotates the screw shaft 47, and linearly moves the moving base 36 to move the pipes 11 and 12 together. The laser displacement meter 67 is caused to move along the central axis in the longitudinal direction, and at the same time, the laser displacement meter 67 is caused to detect the distance between the surface of the groove 13 and the laser displacement meter 67 (step S2 in FIG. 10).

The control unit 100, as shown in FIG.
The shape data of the groove 13 is calculated from the distance data from the laser displacement meter 67 (step S3), and the position coordinates of the groove 13 are calculated from the groove shape data (step S4).
Further, the movement amount of the welding torch 72 is calculated from the coordinate data (step S5 in FIG. 10), the movement amount data is stored (step S6), and then the motor 66 of the distance measuring unit 52 in FIGS. The laser displacement meter 67 is housed inside the moving table 37.

Then, the control device 100 operates the motor 46 that causes the moving base 37 to perform a linear movement along the longitudinal center axis of the pipes 11 and 12 in FIG. 5, and causes the heating units 53 and 53a to move to the groove 13. 6 along with the motors in the feeding mechanism of the heating units 53 and 53a and the motors in the feeding mechanism of the temperature detection unit 55, that is, in FIGS.
By operating a motor corresponding to the motor 66 of the distance measuring unit 52 shown in FIG. 3, each feed mechanism is held until the distance between the tips of the burner 68 and the temperature detector 75 and the surfaces of the pipes 11 and 12 reaches a predetermined value. The table is moved toward the surface of the pipe (step S7 in FIG. 10). When the burner 68 and the temperature detector 75 are positioned, the controller 100
Operates the motor 46 to cause the movable base 36 to swivel the pipes 11 and 12 about the longitudinal center axis, and also operates the gas supply device 69 shown in FIG. 9 to operate the gas burner 68.
To the heating unit 5 by igniting the burner 68.
3, 53a is caused to preheat the groove 13 and both sides of the groove 13 in the pipes 11 and 12, and the temperature detector 75 is operated to measure the temperature of both sides of the groove 13 in the pipes 11 and 12. The detector 75 is made to perform (step S8 of FIG. 10). These preheating and temperature measurement are
The process is repeated until the temperature reaches the set temperature, for example, the temperature reaches 149 ° C. (step S in FIG. 10).
9). When the temperature detector 75 detects a temperature of 149 ° C. or higher, the control device 100 operates the motor in the feeding mechanism of the temperature detection unit 55 to raise the holding base of the unit and move the temperature detector 75 to the moving base. While being pulled inside 37 (step S10 in FIG. 10), the motor 4
6, 51 are operated to move the heating units 53, 53a and the temperature detection unit 55 to the initial positions shown in FIG.

Next, the operator operates the teaching box to teach the groove shape 13. When the teaching is started, the control device 100 calls the groove shape data stored in step S6 of FIG. 10 (step S13), and the groove shape and the distance measuring unit in the motors 46 and 51 and the welding unit 54 in FIG. The relationship between the motor 52 and the operation step of the motor corresponding to the motor 66 is stored (step S11), the motors 46 and 51 in FIG. 5 are operated, and the heating units 53 and 53a and the temperature detection unit 55 are initialized as shown in FIG. Move to position.

When the teaching is over, the controller 100
As shown in FIG. 10, it is determined whether the number of set welding layers is single or plural (step S13), and if the single layer is set, the motor 46 shown in FIG.
After moving the moving table 36 around the central axis of the pipes 11 and 12 in the longitudinal direction to move the welding unit 54 to the initial position (step S14 in FIG. 10), the motor 51 is operated to open the welding unit 54. While moving to the tip 13, the motor in the feed mechanism of the welding unit 54 is operated to lower the holding table until the distance between the tip of the welding torch 72 and the groove 13 reaches a predetermined value. Is moved toward the surface of the pipe (step S1 in FIG. 10).
5). Then, the control device 100 actuates the motor 46 to cause the welding torch 72 to swivel about the longitudinal center axes of the pipes 11 and 12, and at the same time actuates the welding line drive mechanism 73 and the welding power source 74 shown in FIG. 9. Then, the welding unit 54 is caused to perform the main welding under the set welding conditions, and the gas supply device 69 is operated to cause the burner 68 to have the groove 1
3 and the regions on both sides of the groove 13 in the pipes 11 and 12 are heated (step S16 in FIG. 10). When the heating and welding are over, the control device 100 stops the operation of the welding line drive mechanism 73, the welding power source 74 and the gas supplier 69 in FIG. 9, and the motor included in the feed mechanism of the welding unit 54 and the heating units 53, 53a. After the welding torch 72 and the burner 68 are housed inside each unit by reversing that in the feed mechanism (step S in FIG. 10).
17), the motors 46 and 51 are operated, the movable base 36 is rotated, and the welding unit 54 is moved to the initial position.

Then, the control device 100 operates the motor 51 in FIG. 5 to move the distance detecting unit 52 above the groove 13, and also activates the motor in the feed mechanism of the distance detecting unit 52 to hold the holder. After moving the laser displacement meter 67 toward the surface of the pipes 11 and 12 until the distance between the tip of the laser displacement meter 67 and the welding bead reaches a predetermined value (step S1 in FIG. 10).
8) The laser displacement meter 67 is caused to measure the distance from the welding beat (step S19 in FIG. 10). Control device 100
10, after converting the distance data from the laser displacement meter 67 into shape data, it is determined whether or not the shape data includes an undercut (step S
20) If there is an undercut, steps S15 to S21 in FIG. 10 are executed.
If there is no undercut, the control device 100 is shown in FIG.
The motor 66 in the feed mechanism of the distance detection unit 52 shown in FIG. 8 is operated to raise the holding table 64, and the laser displacement meter 67 is housed inside the moving table 37 (step S2).
1).

When the storage is completed, the control device 100 is operated as shown in FIG.
The motor 51 is operated to move the cooling unit 56 onto the welding bead, and the motor in the feeding mechanism of the cooling unit 56 is operated until the distance between the tip of the nozzle 76 and the welding bead reaches a predetermined value. The nozzle 76 is moved toward the pipe surface (step S2 in FIG. 10).
2). When the cooling unit 56 is positioned, the control device 100 opens the opening / closing valve 77 shown in FIG. 9 and operates the motor 46 to cause the nozzle 76 to swirl around the central axis in the longitudinal direction of the pipes 11 and 12. The cooling fluid source 78
The cooling gas from the welding beet and the pipe 11,
The region adjacent to the welding beat in 12 is cooled (step S23 in FIG. 10). When the nozzle 76 turns at the set angle, the control device 100 causes the motor 4 to move.
6 operation is stopped, the on-off valve 77 is closed, and the cooling unit 5
6, the nozzle 76 is housed inside the moving table 37 (step S24 in FIG. 10), the motor 46 and the motor 51 are operated, and the moving table 37 is moved to the initial position shown in FIG. Return and deactivate all components.

Further, when the number n of welding layers set is plural in step S13 in FIG. 10, the control device 100 causes the welding unit 54 to perform the first welding under the set welding conditions as shown in FIG. Welding, heating unit 5
3, 53a is caused to heat the regions on both sides of the groove 13 in the pipes 11, 12 (step S25), and when the heating welding is completed, the executed welding layer number n = 1 is written in the storage unit (step S26). The motor 46 in FIG. 5 is operated to rotate the welding unit 54 to the initial position, and the motor in the feed mechanism of the welding unit 54 is operated to store the welding torch 72 inside the moving table 37 (step S27).

Then, the control device 100 operates the motor 51 shown in FIG. 5 to linearly move the moving table 37 along the central axis of the pipes 11 and 12 in the longitudinal direction to move the distance detecting unit 52 above the groove 13. To operate the motor 66 in the feed mechanism of the distance measuring unit 52, and connect the laser displacement meter 67 to the pipes 11 and 12 until the distance between the tip of the laser displacement meter 67 and the first welding bead reaches a predetermined value. After moving toward the surface (step S28), it is determined whether or not the written value is an even number (step S29). If it is an even number, the motor 46 in FIG. The laser displacement meter 67 is caused to measure the distance between the right groove surface and the welding bead (step S30). If the number is odd, the distance between the left groove surface and the welding bead is measured. Causes the laser displacement meter 67 (step S31). Distance data from the laser displacement meter 67 is sent to the control device 100. The control device 100 starts from the intersection position c between one groove surface a and the welding bead b shown in FIG. 12 or the intersection position e between the other groove surface d and the welding bead b and the initial position of the welding torch 72. Intersection point c
Alternatively, the welding torch movement distance to the intersection point position e is calculated (step S32). When the calculation is done, the control device 1
00 activates the motor 66 in the feed mechanism of the distance detection unit 52 to house the laser displacement meter 67 inside the movable table 37 (step S33). Then, the control device 100 operates the motor 51 shown in FIG. 5 to linearly move the moving base 37 to move the welding torch 72 to the intersection point d or e, and then the welding unit 5
Motor and heating unit 53 in the feeding mechanism 4;
It is operated in the feeding mechanism of 53a, and the welding torch 72 and the burner 68 are moved toward the pipe surface until the distance between the tip of the welding torch 72 and the burner 68 and the welding bead of the first layer becomes a predetermined value (step S3
4) Next, the welding line drive mechanism 73 and the welding power source 74 in FIG. 9 are operated to cause the welding unit 54 to perform the second layer welding under the set welding conditions, and at the same time,
The gas supplier 69 is operated to operate the groove 13 and the pipes 11 and 12.
The burner 68 is caused to perform heating with the adjacent region in step S35. When the second layer of heat welding is completed, the control device 100 writes the number of execution welding layers n = 2 in the storage unit (step S36), and whether the values of the set number of welding layers n and the number of execution welding layers m are the same. Determine (Step S
37), if n = m, steps S18 to S24 are executed. However, if the set number of weld layers and the written number of weld layers do not match, that is, if n ≠ m, steps S27 to S36 are repeated to perform welding work for the third layer, and then n = 3 is written, and again, if the number of executed welding layers is not n = m, steps S27 to S36 are repeatedly executed again until n = m, and when n = m, step S18 is executed.
To step S24 are executed.

[0036]

As described above, the pipe welding machine of the present invention can improve the residual stress of the pipe and perform welding to prevent stress corrosion cracking.
Since the pipes can be joined continuously without changing the equipment required for welding, labor can be saved and the work can be speeded up. It is possible to ensure safety.

[Brief description of drawings]

FIG. 1 shows an embodiment of a pipe welding machine of the present invention,
It is a top view with a part of the welding device omitted.

2 is a front view of the pipe welding machine shown in FIG. 1. FIG.

3 is a side view of the pipe welding machine shown in FIG. 1. FIG.

FIG. 4 is a perspective view around a welding device body in the pipe welding machine shown in FIG.

FIG. 5 is a front view in which a part of the pipe welding machine shown in FIGS. 1 to 4 is cut away and a part thereof is enlarged.

6 is a sectional view taken along line AA of FIG.

FIG. 7 is an enlarged front view of the distance detection unit incorporated in the welding device body in the pipe welding machine shown in FIGS. 1 to 4.

8 is an enlarged side view of the distance detection unit shown in FIG.

9 is an explanatory diagram showing an electrical connection state between a welding device and a control device in the pipe welding machine shown in FIGS. 1 to 4. FIG.

FIG. 10 is a flowchart showing a part of an operating state of the pipe welding machine shown in FIGS. 1 to 4.

FIG. 11 is a flowchart showing the remaining operating state of the pipe welding machine shown in FIGS. 1 to 4.

FIG. 12 is a diagram for explaining a state of multi-layer welding in the pipe welding machine shown in FIGS. 1 to 4.

[Explanation of symbols]

10… Welding equipment 11, 12… Piping 21, 22 ... Arc rail 36 ... The first mobile platform 37 ... Second mobile platform 44 to 46 ... First feeding mechanism 47 ... Straight rail 49, 51 ... Second feeding mechanism 52 ... Distance detection unit 53, 53a ... Heating unit 54 ... Welding unit 55 ... Temperature detection unit 56 ... Cooling unit 63 to 66 ... Third feeding mechanism 100 ... Control device

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Claims (2)

[Claims] 1. A circular arc rail that includes tack welded piping and is arranged in parallel with a weld joint to be formed, a first moving base that travels on the circular arc rail, and a first crossing rail that crosses the circular arc rail. Linear rail arranged on the moving base, a second moving base that travels on the linear rail, a first feed mechanism that makes the traveling of the first moving base, and the traveling on the second moving base. And a preheating unit, a welding unit, and a cooling unit attached to the second moving table via a mechanism that guides the welding joint on the second moving table. A pipe welding machine characterized by. 2. A circular arc rail that includes tack welded piping and is arranged in parallel with a weld joint to be formed, a first moving base that travels on the circular arc rail, and a first rail that intersects the circular arc rail. Linear rail arranged on the moving base, a second moving base that travels on the linear rail, a first feed mechanism that makes the traveling of the first moving base, and the traveling on the second moving base. Preheating unit, temperature detection unit, and welding attached to the second moving table via the second feeding mechanism that moves the welding mechanism on the second moving table and the third feeding mechanism that moves toward the welding joint on the second moving table. A welding device including a unit, a distance detection unit, and a cooling unit, and preheating work of a portion where a welding joint is formed in the preheating unit, temperature measurement of the portion in the temperature detection unit, and setting based on data from the temperature detection unit Up to temperature After the preheating unit is preheated, the welding unit is welded, and then the cooling unit is rapidly cooled to improve the compressive residual stress of the pipe and prevent stress corrosion cracking. A pipe welding machine, comprising: a control device that performs these operations by operating a feed mechanism and a guide mechanism based on data from a distance detection unit.