JPS589775A - Automatic welding device for branch pipe - Google Patents

Abstract

PURPOSE:To copy a groove part accurately and to weld a branch pipe satisfactorily by storing the positions detected with a sensor and positioning a succeeding torch to correct positions. CONSTITUTION:When a pinion 18 is rotated by a motor 19, a carriage 15 starts rotating around the axial line of a branch pipe 2. A sensor 22 detects the groove part. In accordance with the signal thereof, driving motors 23a, 24a for a vertical slider 23 and a lateral slider 24 run and the movement extents thereof are detected with detectors 23b, 24b, then the position of the groove part with respect to the rotating angle of the carriage 15 is stored in a controller. On arriving of a welding torch 10 at the detection start position of the sensor 22, a vertical slider 13 and a lateral slider 14 move is accordance with the signals of the detectors 23b, 24b, and the torch 10 copies the groove part accurately in accordance with the change in the welding groove. According to the rotating angle of the carriage 15, the torch welds the butt parts of a main pipe 1 and the branch pipe 2 in accordance with the control signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic branch pipe welding device for welding a branch pipe onto the outer periphery of a main pipe.

Conventionally, when welding a branch pipe 2 to the outer periphery of a main pipe 1 as shown in Fig. 1, manual welding has been the main method, requiring a high level of skill on the part of the welding operator and resulting in poor welding efficiency. Ta.

2.2 Some attempts have been made to automate the welding of such branch pipes, and automatic welding equipment as shown in FIG. 2 is used. In the automatic welding device shown in FIG. 2, a welding torch 3
It is equipped with a weaving device 4, a torch angle adjustment device 6, a torch rotation device 6, a torch vertical movement device 7, a torch horizontal movement device 8, and a main pipe rotation device 9 that rotates the main pipe 1. Based on the three axes of movement and main pipe rotation, the movement of these axes is controlled by calculation 15, and the welding torch 3 is moved so as to follow a correlation curve that is the joint where the main pipe 1 and the branch pipe 2 are butted, The abutting portions of the main pipe 1 and the branch pipes 2 are automatically welded by setting the aiming angle of the welding torch 3 by calculating and controlling the two axes of the torch angle and torch rotation according to the welding position.

However, in the example shown in FIG. 2, the welding torch 3 is positioned by calculating the interpenetration curve between the branch pipe 2 and the main pipe 1 without having a copying device, and therefore the welding torch 3 is positioned using a relatively small diameter pipe and the main pipe 1. It can be applied when the ratio of the diameter of the branch pipe 2 to the diameter is small and the strain at the time of fusing is small. , it could not be applied when the precision of the groove part was poor.

For this reason, some attempts have been made to develop devices equipped with a sensor for detecting the groove as shown in FIG.

However, as one of the methods, a sensor that follows the outer circumference of the branch pipe 2 is placed at a position B relative to the welding torch 3, and a sensor that follows the outer circumference of the branch pipe 2 is placed at a position B relative to the welding torch 3.
With a device that uses a sensor to copy the outer periphery of the groove, it is impossible to install it close to the welding part 3 to avoid the influence of spatter, so the tracking accuracy is poor, and When the pipe diameter ratio of branch pipe 2 and main pipe 1 approaches 1=1,
As shown in Fig. 4, the contact part of the sensor at position B with the main pipe 1 is separated from the groove part, resulting in poor tracing accuracy, and when the pipe diameter ratio is 1=1, It was impossible to press the sensor at all, and there was a limit to the pipe diameter ratio that could be applied.

In addition, in an example in which a sensor is provided at a position C preceding the welding torch 3 in the welding direction, the sensor at position C must be placed as close to the welding torch 3 as possible.Due to the influence of heat, the life of the sensor will be shortened. As the length became shorter, even though the sensor was brought closer to the welding torch 3, it was still far away from the welding torch 3, so accurate tracing could not be performed.

In another example, a sensor for detecting a groove is provided at a position D opposite to the welding torch 3 on the branch pipe 2, but although rough tracing can be performed, the branch pipe 2 Since the welding torches 3 and D are not necessarily completely symmetrical, and the sensors at the positions D are far apart, they are affected by the accuracy of the workpiece, making it impossible to perform accurate tracing.

For this reason, we developed a branch pipe welding device that can directly detect the welding position, perform accurate tracing regardless of workpiece precision, and be applicable to all pipe diameter ratios, regardless of the pipe diameter ratio between the main pipe and branch pipes. was desired.

The present invention was developed to meet these demands.
The object of the present invention is to provide an automatic branch pipe welding device equipped with a welding groove detection device.

In the present invention, a welding torch is attached via a torch copying device to a cart that is attached to the open end of a branch pipe 61 and rotates around the axis of the branch pipe, and the welding position is opened in advance of the welding torch. A sensor is attached to follow the tip, the position detected by the edger is memorized, and based on the memorized signal, the subsequent welding torch is made to follow the same trajectory as the one detected by the sensor to perform welding.

As a result, the sensor directly detects the groove, stores the detection signal, and when the welding torch reaches the detection position, positions the welding torch at the appropriate position in the groove based on the memorized amount of movement. Therefore, the groove can be accurately traced. Hereinafter, one embodiment of the present invention will be described using the drawing of FIG.

FIG. 6 shows a branch pipe automatic welding device according to an embodiment of the present invention. In FIG.
It is fixed at L. This weaving device 11 includes a slide 61 of a torch angle adjustment device 12 that changes the angle of the welding torch 1o according to the curve of the butt portion of the main pipe 1 and the branch pipe 2. −4 It is fixed in the section.

13 is a vertical slider whose sliding portion moves in the vertical direction (in the axial direction of the branch pipe 2), and the torch angle adjustment device 12 is fixed to the sliding portion of this vertical slider 13;
This vertical slider 13 is connected to a left-right slider 14 whose sliding portion moves in the left-right direction (radial direction of the branch pipe 2).
These parts constitute a welding head main body.

Reference numeral 16 denotes a cart having a left and right slider 14 fixed to a mounting arm 161L. . This truck 16 has a pinion 18
A motor 19 is mounted on the chuck 16, and a large gear 2o with which the pinion 18 meshes is fixed to the chuck 16. Furthermore, the chuck 16 is fixed to the open end of the branch pipe 2 by expanding the claws 21 on the lower surface. Therefore, by driving the motor 19, the pinion 18
is moved while meshing with the large gear 20, 7
, This causes the cart 16 to rotate around the axis of the branch pipe 2,
The welding torch 1o rotates around the branch pipe 2. 22 is a sensor that detects the groove at the position preceding the welding torch 1o.
It is fixed to the sliding portion of the vertical slider 23 via. In addition, the up and down slider 23 is the left and right slider 2.
4, and the left and right sliders 24
is attached to an attachment arm 15b provided at a position facing the attachment arm isa of the truck 16. Furthermore, the drive motor 23 of the lower slider 23 and the left and right sliders 24
Detectors 23b and 24 for detecting the amount of movement of the vertical slider 23 and the horizontal slider 24 are provided at 1L and 24L.
b is installed.

Further, one end of the main pipe 1 is fixed to a rotary table 26 by a claw 26, and is driven to swing around an axis by a main pipe swinging device 27. Furthermore, the other end of the main pipe 1 is rotatably supported by a turning roller 28.

In the branch pipe automatic welding apparatus having the above configuration, when the pinion 18 is rotated by the motor 19, the cart 15 starts rotating around the axis of the branch pipe 2.

At this time, the sensor 22 detects the changing groove, and uses the signal to move the upper and lower sliders 23 and the left and right sliders 24.
The drive motors 231L and 241L operate, and the amount of movement thereof is detected by the detectors 23b and 24b.
The position of the groove for the rotation angle of 6 is stored in a control device (not shown). Then, the cart 16 continues to rotate,
When the welding torch 1o reaches the detection start position of the sensor 22 with a delay, the vertical slider 13 and the horizontal slider 14 are moved based on the signal from the control device, that is, based on the detection signals from the detectors 23b and 24b that have been stored in advance. As the welding torch 1o moves, the welding torch 1o accurately follows the welding groove according to the change in the welding groove. Furthermore, welding conditions such as the angle of the welding torch 10, weaving oscillation frequency, weaving amplitude, welding current, welding voltage, and welding speed are adjusted according to the rotation angle of the cart 160 and based on preprogrammed control signals. , Instead, weld the butt portions of main pipe 1 and branch pipe 2.

At this time, the main pipe swinging device 24 is operated based on a pre-programmed control signal according to the rotation angle of the cart 16, and the main pipe 1 is swung around its axis, so that the welding position is in the horizontal fillet position. By controlling the welding position so that it becomes a substantially downward position, a good welding result can be obtained over the entire circumference of the branch pipe 2.

As described above, according to the branch pipe automatic welding device of the present invention, the groove is directly detected by the sensor, the detection signal is memorized, and the next time the welding torch reaches the detection position, the memorized movement amount is applied to the welding torch. Since the groove is positioned at the appropriate position based on the information, it is possible to accurately trace the groove. This allows distortion during fusing, dimensional tolerances of the workpiece, and temporary attachment of the main pipe and branch pipes to be avoided due to accuracy, etc. Since it is possible to correct the misalignment of the tip and to perform accurate tracing regardless of the pipe diameters of the main pipe and branch pipes, it is possible to perform good welding.

In addition, when performing multi-layer welding, 10,
Since the groove portions are memorized in , , the sensor can be removed from the second and subsequent layers, making it easy to perform accurate welding.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing an example of a welding point between a main pipe and a branch pipe, Fig. 2 is a perspective view showing an example of a conventional branch pipe automatic welding device, and Figs. 3 and 4 respectively show a sensor. FIG. 6 is a perspective view showing an automatic branch pipe welding apparatus according to an embodiment of the present invention. 1... Main pipe, 2... Branch pipe, 10...
... Welding torch, 11 ... Weaving device, 12 ... Torch angle adjustment device, 1'3.23
・・・・・・Up and down slider, 14.24・・・・・・
Left and right slider, 15...Dolly, 16...
...Chuck, 18...Pinion, 19...
...Motor, 2o...Large gear, 22...
...Sensor, 24... Main pipe rocking device. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Figure 5

Claims (1)

[Claims] A welding torch is attached via a torch copying device to a trolley that is attached to the open end of the branch pipe and rotates around the axis of the branch pipe, and a sensor is attached that copies the groove at the welding position that preceded the welding torch. , automatic branch pipe welding characterized in that the position detected by the sensor is memorized, and based on the memorized signal, welding is performed by making a subsequent welding torch follow the same trajectory as the trajectory detected by the sensor. Device.