JP6316896B2 - Building steel pipe column welding method - Google Patents

Description

  The present invention relates to a method for welding steel pipe columns for constructing architectural columns. In particular, it relates to a method of welding a square steel pipe at a construction site.

Joint welding of rectangular steel pipe columns at construction sites is often performed manually by welding technicians.
In large buildings such as high-rise buildings, the dimensions of one side of the box column are as large as, for example, about 800 mm, and the plate thickness is as large as about 80 mm. Therefore, multi-layer welding is required, and skilled skills and construction confirmation management are performed. .
On the other hand, utilization of a welding robot as seen in Patent Document 1 and Patent Document 2 has also been proposed.
However, at the construction site, it is necessary to perform welding while stacking short square steel pipes and temporarily supporting the erection pieces provided on the upper and lower steel pipes while maintaining the posture so as to maintain straightness. In addition, there are parts that cannot be welded by the robot due to obstruction of the temporary support erection jig.
Due to such circumstances, even if robot welding is partially possible, a manual work portion remains.
In addition, when a section delimited by erection pieces or the like is welded from one side, distortion is caused by the preceding welded portion, and the straightness is biased. Or two welding robots are required.
In other words, since the straight part of the opposing surface of one column is welded and lamination welding is performed with a grinder process in the corner part, advanced welding technology is necessary, and the welding work often relies on manual welding. , Work efficiency decreases. Due to the lack of manpower, improvements in welding technology are required.

As an example of automatic welding for welding a square steel pipe column used at a construction site, there are the following two proposals, for example.
In Patent Document 1 (Japanese Patent Laid-Open No. 4-351272) and Patent Document 2 (Japanese Patent Laid-Open No. 2000-135594), a rotating rail is provided near the joint portion of the upper and lower steel pipes, and a welding robot is run on the outer rail. An automatic welding apparatus that performs welding is proposed.
However, in actual sites, there are cases where there are erection pieces and erection jigs that straddle the joints in order to control and maintain the upper and lower rectangular steel pipes directly, and it may not be possible to run around. Then, these proposed technologies cannot be applied.

JP-A-4-351272 JP 2000-135594 A

  In the welding of square steel pipes for construction, the purpose is to realize mechanized welding from the first layer of welding in the situation with a built-in jig and erection piece.

1. In a construction site, a method of welding upper and lower rectangular steel pipes, which are temporarily fixed by connecting erection pieces with a construction jig, using a welding robot,
The square steel pipe has an R corner, and an erection piece is installed on the flat surface of the square steel pipe.
Perform initial welding using a welding robot continuously between adjacent erection jigs,
After the initial welding is completed, the built-in jig is removed and the remaining welding is performed.
Removing the erection piece by gas fusing after the end of welding,
A welding method for square steel pipe columns for construction, characterized by
2. A rectangular steel pipe joint having an R corner at a construction site, in which an erection piece is installed on the four planes of the square steel pipe, and the erection pieces installed on the upper and lower square steel pipes are connected by a built-in jig. A method of welding,
Of the quadrants separated by the built-in jigs provided on the four sides of the joint, the opposing quadrants are welded continuously for the first few layers using a welding robot, and the weld ends are polished. ,
Then, using the other welding robots, the remaining two quarters are similarly welded in succession for the first few layers,
Remove the erection jig,
Using two welding robots, the other half layers are alternately ground, the ends are polished, the remaining several layers are welded, and the welding is completed .
A welding method for a rectangular steel pipe column for construction , wherein the erection piece is removed by gas fusing after the end of welding.
After building the square steel pipe having the R corner part with the erection piece joined to the 3.4 surface at the construction site and temporarily fixing the erection pieces of the upper and lower square steel pipes with the jig,
A guide rail of a circulating welding robot is attached near the joint of one of the upper and lower rectangular steel pipes, and two welding robots are arranged opposite to the rail,
A welding method for a rectangular steel pipe column for construction, wherein the following welding process is performed, and the erection piece is removed by rail removal and gas fusing .
Step A: Teaching the welded parts of the first quarter adjacent to each other across the corner and the welded part of the third quarter facing the first quarter using individual welding robots,
Process B: The welding robot is guided and traveled on the rail, and the first quarter and the third quarter opposite to the first quarter are continuously welded from the first layer. Perform several layers (about 2 to 3 layers) and polish each weld end,
Step C: Teaching the welded portion of the second quarter and the fourth quarter facing the second quarter,
Step D: The welding robot is guided and traveled on the rail, and the second quarter and the fourth quarter opposite to the second quarter are continuously welded from the first layer. Perform several layers (about 2 to 3 layers)
Process E: Remove the built-in jig.
Step F: Run one welding robot for half a circle, teach, weld for the first half, and polish the end.
G process: Run the other welding robot for the remaining half of the circumference, teach, weld the remaining half of the circumference, and polish the end.
Step H: Alternate welding in which one welding robot performs the half-circular welding by the one welding robot and the other welding robot in advance, and the other welding robot performs the half-circular welding after the end polishing. Repeat the required number of times to complete the welding.
4). The speed adjustment of the welding robot from the straight part to the corner part is performed between 10 and 20 mm before the transition to the corner part. ~ 3. The welding method of the square steel pipe pillar for construction as described in any one of.
5 . 1. The bead quality is maintained by performing operation control that keeps the current, voltage, and speed applied to the welding torch constant . ~ 4. The welding method of the square steel pipe pillar for construction as described in any one of.
6 . By connecting the rear end side of the welding torch to the base of the welding robot, the length from the base to the tip of the torch is increased, and the joint of the steel pipe covered with the built-in jig is welded by shaking the neck of the welding robot. It is characterized by the following . ~ 5. The welding method of the square steel pipe pillar for construction as described in any one of.

1. In the welding of square steel pipes for construction, mechanized welding could be realized from the first layer of welding in the situation with a built-in jig and erection piece.
2. In the initial stage of welding, the range divided by the erection jig is welded, then the erection jig is released, and the erection piece is left and alternate welding is performed in half-round units, and then the erection piece is removed. Therefore, welding was possible with the erection piece left. Moreover, fusing of the erection piece can be a post-process of the welding process, and the welding time can be shortened.
3. By making the torch support part of the welding robot closer to the rear end, the torch's protruding length can be lengthened, and the long protruding length allows the torch to reach the groove portion of the gap between the upper and lower erection pieces. The equipment was set so that the welded part covered with the insertion jig could be reached by swinging the neck.
4). By performing welding between the initial laying jigs for each facing section, it is possible to afford to polish the weld end, and in the same way, half-turn alternate welding in the latter half can also afford to polish the end. It is possible to realize welding without connection failure without providing a special wire.

It is a figure which shows the outline of a welding process. It is a figure which shows the outline of this welding robot. It is a figure which shows the operation example of a welding robot. It is a figure which shows the outline of the state welded from the clearance gap between erection pieces. It is a figure which shows an example of the main states of this invention. It is a figure which shows the prior art example of a welding robot.

The present invention is a method for welding a square steel pipe at a construction site, and is a welding method in which a welding robot can be introduced from an initial stage where an erection jig is provided.
For the first two to three layers, the end portions are polished while being welded by the welding robot for each portion divided by the erection jig. After that, the installation jig is removed and alternate welding is performed every half circle. End polishing is performed during this alternate welding to prevent the occurrence of defective welds.
The erection piece is removed by gas cutting after the end of welding. Temporarily, if gas fusing work is performed in the middle of welding, in addition to fusing work time, if the temperature of the steel pipe that rises due to fusing is not cooled, welding cannot be performed, so cooling time is required, and welding time is prolonged. It becomes. In the present invention, since the fusing of the erection piece can be a post-welding process, the fusing of the erection piece can be separated from the welding restriction conditions.
As a concrete realization element, in order to weld the part covered with the erection jig and the gap between the upper and lower erection pieces, we devised a longer torch so that the tip of the torch can be approached obliquely. Specifically, the rear end side of the torch is supported by the welding robot body, or the torch is formed long.
Also, in order to maintain the welding quality of the corner and straight part of the square steel pipe, the robot body was controlled to keep the speed of the tip of the torch constant. The adverse effect on the bead was minimized by changing the penetration speed into the corner between about 10 to 20 mm.

This will be described below with reference to the drawings.
FIG. 1 shows a schematic configuration of the welding process of the present invention.
The welding cross section 11 of the square steel pipe 1 is shown.
The square steel pipe 1 is provided with erection pieces 12a, 12b, 12c, and 12d on four sides in pairs, and erection jigs 13a, 13b, 13c, and 13d that connect the upper and lower erection pieces.
The square steel pipe is provided with a rail 23 that guides and travels the two welding robots 21 and 22.
In FIG. 1A, the first welding robot 21 is divided into a first quarter 11a separated by an erection jig, and the second welding robot 22 is separated into a third quarter 11c separated by an erection jig. The position is shown, and each section is taught using each welding robot.
FIG. 1B shows that the first welding robot and the second welding robot weld about 2 to 3 layers as initial welding portions of the respective first and third quadrants 11a and 11c, and the initial welding layer 41a. , 41c. The weld end is polished to maintain good seam quality with subsequent welds.
1 (c) and 1 (d) show that the first welding robot and the second welding robot are in charge of the second quadrant 11b and the fourth quadrant 11d, respectively, and teaching and initial two to three layers. Welding is performed to form initial weld layers 41b and 41d.
In FIG. 1 (e), since the initial weld layer is formed over the entire circumference, the posture of the upper and lower rectangular steel pipes can be maintained even if the erection jig is removed. At this stage, the four erection jigs 13a, 13b, 13c and 13d are removed, and the welding groove is exposed over the entire circumference.
“Teaching” is an operation of inputting an actual movement to the robot. In this example, the start and end points can be input manually, and the others can be automatically input. However, the teaching operation is appropriately set according to the procedure, such as manually setting the details of the corner portion.

FIG. 1 (f) shows a state in which the first welding robot 21 teaches in charge of the first half 51 including the first quarter 11a and the fourth quarter 11d.
FIG. 1 (g) shows a state in which the first welding robot welds the first layer of the late welding to the first half 51 after polishing and polishes the end.
In FIG. 1 (h), the second welding robot 22 is in charge of teaching the second half 52, which is the combination of the second quarter 11b and the third quarter 11c, and teaching the second half 52 to the latter half. A state where the first layer of welding is welded and the end portion is polished is shown.
FIG. 1 (i) shows a state in which welding is alternately performed for several layers in a preceding state with respect to the second welding robot in which the first half 51 is welded to the second half 52 by the first welding robot. Show. At the timing of this alternate welding, the weld end of the previous layer can be polished, and the occurrence of a weld seam defect can be prevented.
FIG. 1 (j) shows a state in which the first welding robot 21 has completed the welding of all layers and the second welding robot is welding the final layer.
Since the welding robot has a structure connected to the outside such as a power cable, continuous loop welding is not practical and two welding robots are used.
FIG. 1 (k) shows a state where welding has been completed over the entire circumference.
FIG. 1 (l) is a process in which the rail 23 is removed, and the erection pieces 12a, 12b, 12c, and 12d provided on the upper and lower rectangular steel pipes are removed by gas cutting.

In the process shown in FIG. 1, the welding balance is balanced by performing welding at opposite positions by two welding robots and alternately performing half-circular welding, and distortion caused by welding can be prevented. .
It is possible to perform welding with the welding robot from the first layer with the erection jig and erection piece attached.
Since welding is completed before the erection piece is cut, it is not necessary to remove and cool the erection piece on the way, so that the welding time can be greatly shortened.
With almost synchronized movements, two operators can be managed simultaneously by one operator, saving labor.

FIG. 2 is a schematic diagram of the main welding robot. (A) is a basic configuration diagram, and (b) is a diagram equipped with a monitoring device.
The upper and lower rectangular steel pipes 1 and 1 are overlapped, and the erection pieces 12 and 12 provided on the upper and lower rectangular steel pipes are connected by the erection jig 13 so that the postures of the upper and lower rectangular steel pipes are temporarily fixed. A groove 15 serving as a welded portion is formed at the joint between the upper and lower rectangular steel pipes.
The welding robot 2 is configured by attaching a rail 23 to the upper rectangular steel pipe 1, connecting a traveling carriage 25 to the rail 23, and connecting the traveling carriage 23 and the torch 24 with a base body 26. This welding robot is accompanied by a power cable, a weld metal wire, etc., but is omitted.
The tip of the torch is positioned so as to face the groove 15 and welding is performed. As shown in FIG. 2 (a), if there are upper and lower erection pieces, the gap into which the torch is inserted is limited, so if the torch is short, it will not reach the groove, and the welding robot cannot be used. Become.
In the present invention, by developing a long torch, the torch reaches the groove from the gap of the erection piece.
As a reference, FIG. 6 shows an example of a welding robot provided with a conventional length torch. In this conventional example, since the intermediate part of the length of the torch is connected to the base body, the length to the tip of the torch is limited, and it is difficult to reach the groove from the gap of the erection piece.
On the other hand, in the improved example of FIG. 2, the protruding length of the torch can be increased by connecting the rear end portion of the torch to the base.
When lengthening the torch, in order to stabilize the posture of the tip of the torch, the weight is reduced by using a weight reducing material such as a carbon fiber on the torch base side. Furthermore, the control operability of the torch is improved by connecting the rear side of the torch to the base, making the tip side longer, and attaching an adjusting weight as a balancer to the rear end of the torch.
Furthermore, in FIG.2 (b), since the monitoring camera 27 which can observe a welding state realistically is attached to the torch, the quality of welding can be confirmed during welding.
It is important to manage the base material temperature (temperature between passes) for quality control of welding. In the present invention, when an infrared thermography is employed as the monitoring camera 27, the temperature between passes can be directly managed. Generally, control is performed so that the next pass is not welded until the temperature of the base material falls to 250 ° C. to 350 ° C. or lower.
If two welding robots are used alternately and the other welding robot is set to operate within this temperature drop time, the working time can be shortened and basic temperature management can be performed.

FIG. 3 shows an operation example of the welding robot.
The operation of the welding robot will be described using the first quarter 11a as an example.
The welding of the square steel pipe 1 starts from the erection piece 12a connected by the erection jig 13a, and the first welding robot 21 welds the section to the erection piece 12b connected by the erection jig 13b. 1 quarter 11a.
Since the starting place S of the square steel pipe 1 has the erection jig 13a, the welding robot 21 swings the head from the vicinity of the erection jig 13a so that the torch 24 faces the starting part S. The torch 24 is returned from the start location S to the location B1 facing the square steel pipe. The welding robot 21 travels in a straight line up to the corner start point C1 in a state of facing directly. The traveling of the traveling carriage of the welding robot 21 traveling on the outer rail is controlled so that the speed of the torch in the corner portion is maintained at the same level as that of the straight portion. If the speed of the traveling carriage is intermittently changed, there is a risk of a shock that may tear the weld bead. Therefore, it is desirable to provide a buffer distance of about 10 to 20 mm for the speed change.
The corner portion is from the start location C1 to the end location C3 via the central location C2. Thereafter, the welding is performed through the straight portion, and swing welding is performed in the vicinity of the erection jig 13b at the end portion.
As with the start point S, the end point E covered with the erection jig 13b is subjected to welding by shaking the neck. As the head swings to reach the end point E, the point where the head is swung is set as a head start point B2, and the end point E is accessed gradually from this point.
The welding of the straight part and the corner part is controlled so as to keep the current, voltage and speed constant, thereby maintaining the welding quality. In the generation of beads, the deterioration and tearing of beads do not occur by managing these welding conditions constant. Since the rail makes a large turn at the corner portion, the traveling speed of the traveling carriage of the welding robot is adjusted in order to keep the speed of the torch portion constant. If the speed changes suddenly at the entrance of the corner, the bead becomes thin and there is a risk of tearing. Therefore, the speed of the traveling carriage is adjusted by taking 10 to 20 mm as a buffer distance.

FIG. 4 shows an outline of a state where welding is performed from a gap between the erection pieces.
The groove 15 provided by the upper and lower steel pipes may be a narrow groove of about 25 degrees, for example. In this way, when the opening angle is small and there is a gap between the upper and lower erection pieces 12, 12, in the present invention, since the extension length of the torch 24 is long, the groove can be accurately accessed from the gap between the erection pieces. it can. The first layer of welding can be welded in one pass. However, since the groove is expanded after the second layer, it is necessary to finish the entire layer in several steps. For example, the number of passes increases to 2 passes for 2 layers, 3 passes for 3 layers, and the like. It is also necessary to adjust the passage location of the tip of the torch.

FIG. 5 shows an example of the main state of the present invention.
FIG. 5 (a) shows a state in which the rails 23 are installed around the square steel pipe 1 in which the erection pieces 12 and 12 of the upper and lower square steel pipes are temporarily fixed by the installation jig 13, and the welding robot 2 is attached to the rail. Is shown. This corresponds to the state shown in FIG.
FIG. 5B shows a state in which the initial several layers are welded every quarter in the state of FIG. 5A and the erection jig 13 is removed from the square steel pipe. Since temporary fixation is maintained by welding for several initial layers, the erection jig can be removed. This corresponds to the state shown in FIG.
In this state, alternate welding is performed every half turn until the final welding.
FIG. 5 (c) shows a state where the erection piece is removed by gas fusing after the end of welding. The erection piece mark 16 removed by fusing remains in the square steel pipe 1. The rail 23 and the welding robot 2 are removed.
When the gas is blown, the temperature of the square steel pipe rises, so it is necessary to allow a cooling period. However, in this step, since the gas blow can be performed after the welding step, the welding time is not extended.

  FIG. 6 shows a welding robot 120 having a conventional torch length as a reference example. A traveling carriage 125 is attached to the rail 23, and a base body 126 is provided between the traveling carriage 125 and the torch 124. In this conventional example, since the intermediate portion in the longitudinal direction of the torch 124 is connected to the base 126, the length to the tip of the torch is limited, and the torch can reach the groove from the gap between the erection pieces 12 and 12. It is difficult.

  The above has shown an example in which a total of four erection pieces are provided on each side of the square steel pipe, but the present invention can also be applied to a square steel pipe provided with two erection pieces on each side. There is no limit to the number of pieces. The present invention can be applied if there is enough space between adjacent erection pieces to allow the welding robot to be introduced.

DESCRIPTION OF SYMBOLS 1 Square steel pipe 11 Welding cross section 11a 1st quarter part 11b 2nd quarter part 11c 3rd quarter part 11d 4th quarter part 12, 12a, 12b, 12c, 12d Erection piece 13, 13a, 13b, 13c, 13d 15 Groove 16 Erection piece mark

2, 21, 22 Welding robot 23 Rail 24 Torch 25 Traveling carriage 26 Base 27 Monitoring camera 41a, 41b, 41c, 41d Weld layer 51 First half 52 Second half 120 Welding robot 124 Torch 125 Traveling carriage 126 Base

S start location C1 start location C2 center location C3 end location E end location B1 swing start location B2 swing start location

Claims (6)

In a construction site, a method of welding upper and lower rectangular steel pipes, which are temporarily fixed by connecting erection pieces with a construction jig, using a welding robot,
The square steel pipe has an R corner, and an erection piece is installed on the flat surface of the square steel pipe.
Perform initial welding using a welding robot continuously between adjacent erection jigs,
After the initial welding is completed, the built-in jig is removed and the remaining welding is performed.
Removing the erection piece by gas fusing after the end of welding,
A welding method for square steel pipe columns for construction, characterized by A rectangular steel pipe joint having an R corner at a construction site, in which an erection piece is installed on the four planes of the square steel pipe, and the erection pieces installed on the upper and lower square steel pipes are connected by a built-in jig. A method of welding,
Of the quadrants separated by the erection jig provided on the four sides of the joint, the opposing quadrants are
Welding the first few layers continuously using a welding robot, polishing the weld end,
Then, using the other welding robots, the remaining two quarters are similarly welded in succession for the first few layers,
Remove the erection jig,
Using two welding robots, the other half layers are alternately ground, the ends are polished, the remaining several layers are welded, and the welding is completed .
A welding method for a rectangular steel pipe column for construction , wherein the erection piece is removed by gas fusing after the end of welding. After building a square steel pipe having R corners with four erection pieces joined on the construction site and temporarily mounting the erection pieces of the upper and lower square steel pipes with a jig,
A guide rail of a circulating welding robot is attached near the joint of one of the upper and lower rectangular steel pipes, and two welding robots are arranged opposite to the rail,
A welding method for a rectangular steel pipe column for construction, wherein the following welding process is performed, and the erection piece is removed by rail removal and gas fusing .
Step A: Teaching the welded parts of the first quarter adjacent to each other across the corner and the welded part of the third quarter facing the first quarter using individual welding robots,
Process B: The welding robot is guided and traveled on the rail, and the first quarter and the third quarter opposite to the first quarter are continuously welded from the first layer. Perform several layers (about 2 to 3 layers) and polish each weld end,
Step C: Teaching the welded portion of the second quarter and the fourth quarter facing the second quarter,
Step D: The welding robot is guided and traveled on the rail, and the second quarter and the fourth quarter opposite to the second quarter are continuously welded from the first layer. Perform several layers (about 2 to 3 layers)
Process E: Remove the built-in jig.
Step F: Run one welding robot for half a circle, teach, weld for the first half, and polish the end.
G process: Run the other welding robot for the remaining half of the circumference, teach, weld the remaining half of the circumference, and polish the end.
Step H: Alternate welding in which one welding robot performs the half-circular welding by the one welding robot and the other welding robot in advance, and the other welding robot performs the half-circular welding after the end polishing. Repeat the required number of times to complete the welding. The method for welding a square steel pipe column for building according to any one of claims 1 to 3, wherein the speed adjustment of the welding robot from the straight part to the corner part is performed between 10 and 20 mm before the transition to the corner part. . The square steel pipe column for building according to any one of claims 1 to 4 , wherein the quality of the bead is maintained by performing operation control for maintaining a constant current, voltage, and speed applied to the welding torch. Welding method. By connecting the rear end side of the welding torch to the base of the welding robot, the length from the base to the tip of the torch is increased, and the joint of the steel pipe covered with the built-in jig is welded by shaking the neck of the welding robot. The welding method of the square steel pipe column for constructions in any one of Claims 1-5 characterized by the above-mentioned.

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