JPH08215841A - Circumference butting welding equipment of fixed tube - Google Patents

Abstract

PURPOSE: To provide circumference butting welding equipment of fixed tube capable securing good welding quality even though there is variation in the circumferential direction of both root gap of welding groove and groove width. CONSTITUTION: To an automatic welding machine 14 having function to control/ adjust a position of welding torch, a camera 51 to pick up image of groove part, a groove dimension detecting means to detect variation in the circumferential direction from the pick up image information and a computing element to select suitable welding condition from the optimum welding condition data base corresponding to the variation are added. By this method, in the circumference butting welding, joining of the end of welding bead is well executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding device for performing circumferential butt welding of fixed pipes such as pipelines.

[0002]

2. Description of the Related Art As a welding device for circumferentially butt-welding a fixed pipe, the device disclosed in Japanese Patent Laid-Open No. 4-200866 is known.

FIG. 7 is a perspective view of the circumferential butt welding apparatus for a fixed tube disclosed in the above-mentioned Japanese Patent Laid-Open No. 4-200866.

In FIG. 7, reference numeral 20 denotes a traveling guide rail which is arranged on the outer periphery of the fixed pipe 10 to be butt-welded and which is supported by a support 201. Reference numeral 21 is an automatic welding machine which is guided by the traveling guide rail 20 and travels on the outer circumference of the fixed tube 10 in the circumferential direction.

The automatic welding machine 21 has a Z-direction traveling means 22 having a Z-direction drive motor 224 for controlling traveling in the circumferential direction and an X-direction for controlling movement of the welding torch 26 in the groove width direction. X direction position control means 23 having a direction moving mechanism 231 and an X direction driving motor (not shown), a Y direction moving mechanism 241 and a Y direction driving motor (for controlling the movement of the welding torch 26 in the height direction). (Not shown) and a Y direction position control means 24, and a β direction angle adjusting plate 25 for adjusting the welding direction inclination angle of the welding torch 26.
1 and a β-direction drive motor 252, and a rotation motor 2 for rotating the welding torch at a high speed.
The welding torch 26 having 62 and the welding wire supply device 27 having the wire reel 274 and the wire supply motor 272 for supplying the welding wire to the welding torch 26 are provided.

[0006]

When performing on-site welding work for pipelines, it is important to improve welding efficiency and at the same time ensure good welding quality.

When butt-welding fixed pipes such as pipelines, the root gap and groove width usually fluctuate in the circumferential direction of the fixed pipe due to error in centering work and thermal deformation during butt welding. is there. Further, such a variation in the root gap is likely to lead to unevenness of the back bead width and height in the first layer welding, and a variation in the groove width is likely to cause excess or deficiency of the amount of deposited metal in the laminated welding.

Therefore, in order to ensure good welding quality, the welding conditions such as welding current and welding speed are appropriately adjusted and controlled during the welding operation in accordance with such variations in the root gap and the groove width. It is necessary to weld them.

However, the welding apparatus disclosed in the above-mentioned Japanese Patent Laid-Open No. 4-200866 does not disclose anything about dealing with the above-mentioned fluctuations in the root gap and the groove width.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to secure a good welding quality even if there are variations in the root gap and the groove width. It is intended to provide a welding device.

[0011]

SUMMARY OF THE INVENTION A circumferential butt welding apparatus for a fixed pipe according to the present invention comprises a traveling guide rail installed in the vicinity of a circumferential butt welding portion of the fixed pipe, and a fixed pipe guided by the traveling guide rail. And a Z-direction traveling means for traveling in the circumferential direction of the fixed pipe and a welding torch groove width. X-direction position control means for moving and controlling the welding torch in the height direction, Y-direction position control means for moving and controlling the welding torch in the height direction, and β-direction torch angle adjusting means for adjusting the inclination angle of the welding torch in the welding direction, A root gap value based on the groove image pickup camera having the welding torch having a function of rotating the welding arc at high speed and attached to the X direction position control means, and the groove image pickup information from the camera. And groove width value detecting means for detecting groove width value, optimum welding condition database storing optimum welding conditions for each root gap value and groove width value, and root gap detected by the groove size detecting means. A computing unit that selects and outputs an appropriate value from the optimum welding condition database according to the value or the groove width value, and a welding control unit that controls welding conditions by the output from the computing unit. Is a circumferential butt welding device for a fixed pipe.

Further, in the above-mentioned fixed pipe circumferential butt welding apparatus, a dog piece for position detection is attached at a position corresponding to the welding start end and the end of the traveling guide rail, and the proximity detector for detecting the proximity of the dog piece is automatically operated. It is desirable to attach it to a welding machine.

[0013]

The groove image pickup camera and the groove size detecting means detect variations in the root gap value and the groove width value. Next, the computing unit selects welding conditions such as appropriate welding current and welding speed from the optimum welding condition database according to the detected root gap value or groove width value and outputs them to the welding condition control unit. . Then, based on that, the welding condition control unit adjusts and controls the welding conditions such as the welding current and the welding speed to carry out the welding work. Welding quality can be obtained.

Further, since the proximity detector attached to the automatic welding machine detects the dog piece attached to the traveling guide rail, it can be detected that the automatic welding machine has approached the welding start start end point position. The position control in the circumferential direction of the automatic welding machine such as starting or stopping of the automatic welding machine becomes easy, and the progress of the welding work becomes smooth.

[0015]

EXAMPLES The present invention will be described with reference to examples.

FIG. 1 is a side view of a circumferential butt welding apparatus for a fixed tube according to the present invention. In FIG. 1, 14 is an automatic welding machine, and 20 is a running guide rail arranged on the outer periphery of the fixed pipe 10 to be butt-welded. Reference numeral 201 denotes a support body that supports the traveling guide rail 20, and the support body 201 is composed of a magnet, a suction cup, and the like. In addition, 11 is a groove and the backing material 12 is applied.

Reference numeral 22 is a Z-direction traveling means of the automatic welding machine 14. The guide wheel 225 rolls against the side portion of the traveling guide rail 20, and the rack 206 integrally provided on the outer periphery of the traveling guide rail 20 meshes with a pinion 226 linked to the Z-direction drive motor 224. Although not shown, an encoder for calculating the traveling distance is mounted so that the circumferential position on the fixed pipe of the automatic welding machine 14 can be known.

The automatic welding machine 14 travels on the circumference of the fixed pipe 10 by the Z-direction travel means 22 as described above.

Reference numeral 23 is an X-direction position control means for controlling the movement of the welding torch in the groove width direction.
1 is a structure in which 1 is driven by the X-direction drive motor 232.

The X-direction moving means 23 reciprocates the Y-direction moving means 24 in the groove width direction via the push rod 233.

The Y-direction moving means 24 is for controlling the movement of the welding torch in the height direction, and has a structure in which the Y-direction moving mechanism 241 is driven by the Y-direction drive motor 242.

The Y-direction moving means 24 moves the β-direction torch angle adjusting means 25 attached thereto in the height direction.

The β-direction torch angle adjusting means 25 is for adjusting the welding direction inclination angle β of the welding torch.
This is a structure in which the β-direction angle adjusting plate 251 to which the welding torch 26 is attached is driven by the β-direction drive motor 252.

FIG. 2 is a view on arrow A of FIG. In FIG. 2, the arc-shaped guide rail 257 has a radius around the welding arc point, and the upper and lower surfaces of the arc-shaped guide rail 257 have upper rolling wheels 2 of the β-direction angle adjusting plate 251.
55 and the lower rolling wheel 256 are in rolling contact with each other. further,
A rack 254 is formed on the upper portion of the β-direction angle adjusting plate 251, and a pinion 253 connected to the β-direction drive motor 252 is meshed with the rack 254.

Further, the welding torch 26 is connected to a welding head portion 263 which incorporates a rotation drive means for forming a high speed rotating arc, a shield gas supply means and the like.

In FIG. 1, reference numeral 27 is a welding wire supply device for supplying the welding wire 31 to the welding torch 26, which includes the wire reel 274 and the wire supply motor 2.
72, wire straightening roller 273, and wire feeding roller 2
75 and a feeding roller pressing mechanism 276.

In FIGS. 1 and 2, an image pickup box 50 having a groove image pickup camera 51 and a light 52 is attached to the side surface of the Y-direction position control means 24 via a support plate 54. The imaging box 50 moves together with the welding torch 26 in the groove width direction so that the relative position to the welding torch does not change, and the welding torch moves in the height direction by welding bead height control or the like. Also has a structure that does not follow the movement of the welding torch 26 so that the field of view and focus of the imaging camera do not change. Reference numeral 53 is a power supply and control cable for the camera 51 and the light 52, and 55 is a welding spatter prevention plate.

FIG. 3 is a welding condition control block diagram of the fixed pipe circumferential butt welding apparatus of the present invention.

In FIG. 3, the picked-up image picked up by the groove portion pick-up camera 51 is taken into the image memory 62. Next, the computing unit 61 detects the root gap end position and the groove width end position by performing appropriate image processing on the groove width direction luminance distribution of the captured image, and thereby, the route Calculate the gap value and groove width value. That is, the image memory 62 and the arithmetic unit 61 constitute a groove size detecting means. Then, the computing unit 61, in accordance with the root gap value and the groove width value obtained above, the welding current for each of the root gap value, the groove width value and the welding posture,
Select the appropriate welding condition from the optimum welding condition database 65 that stores the optimum welding conditions such as welding voltage, welding speed, welding torch angle, etc.
Is output to the welding condition control unit 66 via. And
The welding condition control unit 66 stores the information, delays the distance between the imaging camera 51 and the welding torch 26 in the welding advancing direction, and adjusts and controls the welding conditions such as the welding current and the welding speed to perform welding. Carry out the work.

In this way, good welding quality can be obtained even if the root gap value and the groove width value vary.

Reference numeral 64 denotes a monitor TV, which can monitor a picked-up image of the groove portion and an image-processed image.

In the case where welding work is carried out using the above-described fixed pipe circumferential butt welding apparatus of the present invention, two automatic welding machines 14 are used from the viewpoint of welding efficiency and the like. It is conceivable to adopt a method of welding the right half circumference and the left half circumference of the fixed tube, respectively. In that case, in the circumferential butt welding device of the fixed pipe described above, the welding start end (0 o'clock position)
Alternatively, a dog piece 71 such as a magnetic body showing the end portion (6 o'clock position) is attached to the traveling guide rail 20, and the dog piece 7
It is desirable to attach the proximity detector 72 such as a magnetic sensor for detecting the magnetism of No. 1 to the automatic welding machine 14.

As a result, the proximity detector 72 detects the dog piece 71 to detect that the automatic welding machine 14 has approached the welding start start end point and the welding end position. It becomes easy to control the starting and stopping of the welding, and the welding work can proceed smoothly. As a result, at the start and end of welding, the trailing weld bead can be joined to the leading weld bead within a short time, and the end of the weld bead can be joined well. The proximity detector 72 may be replaced with a limit switch.

Next, FIGS. 4 (a) to 6 (p) show the steps in the case of butt welding the fixed pipe 10 using two automatic welding machines 14a and 14b. Tube 10
The dog pieces 71 described above are set at the 0 o'clock position which is the upper part and the 6 o'clock position which is the lower part.

(A) FIG. 4 (a): Automatic welding machine 14 on the left side
b moves to the 0 o'clock position. (B) FIG. 4B: When the proximity detector of the automatic welding machine 14b detects the 0:00 position at the dog piece position at 0:00, the set is turned on. (C) FIG. 4C: The automatic welding machine 14b starts moving, the positions of the camera 51 and the light 52 are set to the 0 o'clock position, the camera 51 operates, and the light 52 lights up. (D) FIG. 4 (d): The automatic welding machine 14b moves forward and detects the route gap value corresponding to the distance between the camera 51 and the welding torch. (E) FIG. 4 (e): The automatic welding machine 14b returns to the same position as in FIG. 4 (a) and stops. At the same time, the automatic welding machine 14a starts moving. (F) FIG. 4 (f): The automatic welding machine 14a is set on when the dog piece position at 0 o'clock is detected by the proximity detector. (G) FIG. 5 (g): The automatic welding machine 14a starts moving, and the positions of the camera 51 and the light 52 are set to the 0:00 position. (H) FIG. 5 (h): The camera 51 of the automatic welding machine 14a is activated and the light 52 is turned on. (I) FIG. 5 (i): The automatic welding machine 14a moves forward and detects the route gap value corresponding to the distance between the camera 51 and the welding torch. (V) FIG. 5 (j): The automatic welding machine 14a is stopped and the welding torch is set at the 0 o'clock position. (L) FIG. 5 (k): An arc is ignited by the welding torch of the automatic welding machine 14a, the camera 51 is activated, the light 52 is turned on again, and welding is started. In the step of FIG. 5 (i), the route gap value corresponding to the distance between the camera 51 and the welding torch is detected, so that appropriate welding conditions corresponding to it have already been set. After that, the automatic welder 14a selects appropriate welding conditions corresponding to the detected route gap value, and continues the welding on the right half circumference while performing delay control for the distance between the camera position and the welding torch position. In addition, in FIG.
The automatic welding machine 14b is also switched on and starts traveling to the 0 o'clock position. (W) FIG. 5 (l): The automatic welder 14b is turned on when the 0 o'clock position is detected, the arc is ignited, the camera 51 is activated, and the light 52 is turned on, as in the case of the welding on the right half circumference. Then, welding is started. In the step of FIG. 4D, the root gap value corresponding to the distance between the camera 51 and the welding torch is detected, so that appropriate welding conditions corresponding to it have already been set. After that, the automatic welder 14b selects appropriate welding conditions corresponding to the detected route gap value, and continues welding on the left half circumference while performing delay control for the distance between the camera position and the welding torch position. (W) Figure 6 (m): Welding on the right half circle ends at 6 o'clock,
Welding on the left half is being continued. (F) FIG. 6 (n): The automatic welding machine 14a detects the position with the dog piece at the 6 o'clock position, the arc is stopped, the operation of the camera 51 is stopped, and the light 52 is turned off. Start traveling to 4 (a)). The welding of the automatic welder 14b ends at the 6 o'clock position. (Y) FIG. 6 (o): The state where the left and right automatic welders 14a and 14b are returning to the standby position is shown. (Vi) FIG. 6 (p): Shows a state in which the left and right automatic welders 14a and 14b have returned to the standby position. (The same as FIG. 4A) The above is the case of the first layer welding, but after the layered welding, the root gap value may be replaced with the groove width.

[0036]

[Effects of the Invention] In the field construction of a pipeline, when the fixed pipes are butt-welded to each other in the circumferential direction, even if the root gap or groove width of the groove fluctuates in the circumferential direction of the fixed pipe, the fluctuation is detected. Since it is possible to set appropriate welding conditions according to the fluctuation, good welding quality is secured.

Further, when welding the right half circumference and the left half circumference of the fixed pipe by using the two automatic welding machines, since the proximity detector for detecting the dock piece is attached, the two automatic welding machines are automatically welded. The order of movement of the machine can be smoothly performed, and the welding bead end portions at the welding start and end portions can be spliced well.

[Brief description of drawings]

FIG. 1 is a side view of a circumferential butt welding apparatus for a fixed pipe according to the present invention.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a block diagram of welding condition control in the circumferential butt welding apparatus for a fixed pipe of the present invention.

4 (a) to (f) are welding process diagrams when two automatic welding machines are used in the present invention.

5 (g) to (l) are welding process diagrams when two automatic welding machines are used in the present invention.

6 (m) to (p) are welding process diagrams when two automatic welders are used in the present invention.

FIG. 7 is a view showing a conventional fixed tube butt welding apparatus.

[Explanation of symbols]

 10 Fixed Pipe 11 Groove 12 Backing Material 14 Automatic Welding Machine 20 Travel Guide Rail 201 Support 206 Rack 22 Z Direction Travel Means 224 Z Direction Drive Motor 225 Guide Wheel 226 Pinion 23 X Direction Position Control Means 231 X Direction Moving Mechanism 232. X direction driving motor 233 Push rod 24 Y direction moving means 241 Y direction moving mechanism 242 Y direction driving motor 25 β direction torch angle adjusting means 251 β direction angle adjusting board 252 β direction driving motor 253 Pinion 254 Rack 255 Upper rolling wheel 256 Lower part Rolling wheel 257 Arc guide rail 26 Welding torch 262 Rotation motor 263 Welding head 27 Welding wire feeder 272 Wire feeding motor 273 Wire straightening roller 274 Wire reel 275 Wire feeding roller 276 Feeding roller Pressing mechanism 3 1 Welding wire 50 Imaging box 51 Groove imaging camera 52 Light 53 Control cable 54 Support plate 55 Welding spatter prevention plate 61 Calculator 62 Image memory 63 Optimal welding condition database 64 Monitor TV 65 Digital input / output circuit 66 Welding condition control unit 71 Dogbees 72 proximity detector

Claims (2)

[Claims] 1. A traveling guide rail installed in the vicinity of a circumferential butt welding portion of a fixed pipe, and an automatic welding machine for traveling along the circumference of the fixed pipe guided by the traveling guide rail to perform welding by a high-speed rotating arc welding method. The automatic welding machine consists of
Z-direction traveling means for traveling in the circumferential direction of the fixed pipe,
An X-direction position control means for controlling the movement of the welding torch in the groove width direction, a Y-direction position control means for controlling the movement of the welding torch in the height direction, and a β-direction torch for adjusting the welding direction inclination angle of the welding torch. In a circumferential butt welding apparatus for a fixed pipe having an angle adjusting means and the welding torch having a function of rotating a welding arc at a high speed, a groove portion imaging camera attached to the X direction position controlling means, and the camera A groove size detecting means for detecting a root gap value and a groove width value from the groove image information of the groove, an optimum welding condition database storing optimum welding conditions for each of the root gap value and the groove width value, and the groove. An arithmetic unit for selecting and outputting an appropriate value from the optimum welding condition database according to the root gap value or groove width value detected by the dimension detecting means, and the arithmetic unit Circumferential butt welding apparatus fixed tube, characterized in that it comprises a welding control unit for controlling the welding conditions by the output. 2. A dog piece for position detection, which is attached to a position corresponding to a welding start end and an end of a traveling guide rail, and a proximity detector which is attached to an automatic welding machine and senses the dog piece. 1. A circumferential butt welding device for a fixed pipe according to 1.