JP2765677B2 - Method and apparatus for cleaning weld bead - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for cleaning a weld bead which removes slag on the surface of a bead and facilitates welding of a next layer when performing automatic welding of a multi-layer pile in processing of a steel frame for a building. .

[0002]

2. Description of the Related Art In recent years, steel frames (S) and steel bars (SR
C) There is an increasing demand for steel frames for structures such as structures or civil engineering structures. When such a steel column material has a closed cross-sectional shape such as a quadrilateral or a circle, a welded joint such as a groove or a V-groove is used for a joint portion or a longitudinal joint portion, and a processing plant is used. It is usual that the entire circumference is welded by a welding robot.

An example will be described with reference to FIG. This figure is a perspective view showing the column braid welding at the steel processing factory.
Is a column material, 21 is a welding robot main body, 22 is a welding torch, 23 is a welding wire supply device, 24 is a nozzle cleaner, 25 is a robot traveling cart, 26 is a positioner, 27 is a welding power supply device, 28 is a shielding gas supply device, 29 is a control device including a personal computer and the like.

The pillar 10 has a long axis in a horizontal position, and a welding torch.
Positioner 26 so that 22 can always perform welding in a downward position
To be rotatable. The welding robot body 21 is an articulated type and performs gas shield welding such as carbon dioxide welding and MAG welding. According to the welding method, particularly in carbon dioxide welding, spatters and the like adhere to the welding torch 22 and a shield gas nozzle around the torch 22 and cause blow holes due to poor shielding. Programming is performed to move the welding torch 22 to the nozzle cleaner 24 to expose the tip and clean the nozzle portion. About 3 times for cleaning
It takes ~ 4 minutes.

FIG. 7 is a front view showing an example of a welded joint at the end of a column, and FIG. 8 is a detailed view showing a groove portion. This pillar 10 is a prism having a side of 1000 mm, and the skin plate 11
The end plate 12 is joined to an end of this having a thickness of 25 to 28 mm. Root gap of groove part is 6-8mm, groove angle 35
8, carbon dioxide arc welding or MAG welding of 6 layers and 7 passes is performed as shown in FIG. The number in ○ indicates the number of passes.

[0006] By welding, a slag layer is formed on the bead surface. The new pass will be welded over the slag layer of the previous pass. Since the slag has electrical conductivity in the molten state, for example, when welding is performed continuously in a steady state as in the case of a cylinder, the slag is re-melted by welding heat due to the approach of the torch, but there is no problem, In the case where welding cannot be performed continuously at a prism, a joint portion, or the like, or in the case of welding that requires cleaning with a nozzle cleaner as described above, it is necessary to turn off the arc once and restart it. At this time, since the slag in the previous pass is solidified and becomes a non-conductor, the arc may not start in some cases, and this tendency is remarkable in the subsequent pass in which the slag is accumulated.

[0007] In the case where welding is performed manually as in the past or when personnel for monitoring are arranged, the slag is removed on a case-by-case basis and restarted, so there is no particular problem. However, if welding robots were used to perform unattended work, the arc would not start and the work would be interrupted, often not being detected for a long time, which would seriously hinder production planning. , Measures have come to be desired.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above problems and realizes a welding bead cleaning apparatus for reliably removing slag before welding in order to efficiently perform automatic welding by a robot. The purpose is to do.

[0009]

According to the present invention, an arm which can be moved up and down by an elevating mechanism is attached to the upper end of a column erected on a bogie, and a continuous striking device is attached to the tip of the arm via a spring. And a pair of guide rollers attached to the tip of a Y-shaped bracket extending from the upper end of the holder.

Further, preferably, the continuous hitting device has a bundle of hard steel wires loaded at the tip of an air hammer,
A continuous beating apparatus is a welding bead cleaning apparatus in which a continuous hitting apparatus is mounted obliquely in accordance with a groove shape, and a bogie can run on a rail and can be positioned at a welding joint position.

[0011]

According to the present invention, welding in a welded joint for welding a groove having a closed cross-section such as a quadrilateral or a circle in a horizontal posture in a multi-layered manner in a groove plane perpendicular to the axis of the column while appropriately rotating the column. In the bead cleaning device, the weld bead is continuously struck at the lower portion of the weld joint that precedes the weld torch by half a circle to remove and remove the slag on the bead surface of the previous pass. Since the weld metal is exposed on the bead surface, even if the arc is interrupted once, it restarts smoothly and the production is not interrupted even in the unmanned operation.

[0012]

An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view of a bead cleaner, and FIG. 2 is a side view of the same. 1 is a cleaner main body, 2 is a pair of guide rollers attached to both sides of the cleaner main body 1,
3 is a holder to which the cleaner body 1 is attached via a spring, 4 is an arm with the holder 3 suspended at its tip, 5 is an elevating cylinder such as an air cylinder for vertically elevating the arm, and 6 is a guide rod for guiding elevating. 7 is a support, 8
Is a traveling truck of the cleaner, and 9 is a rail.

This bead cleaner is mounted on a bogie 8 which is positioned by traveling on a rail 9 installed in a direction perpendicular to the welding line, for example, in the case of the column shown in FIG. An arm 4 is attached to the upper end of an upright supporting column 7 so as to be able to move up and down, and a holder 3 to which the cleaner main body 1 is attached is pivotally attached to the tip of the arm 4 via a spring.

The cleaner main body 1 is commercially available as a so-called "jet tag" in which a bundle of hard steel wires is loaded at the tip of an air hammer. This tool is used to strike a surface continuously, remove welding beads, remove rust before painting steel materials, and roughen various surfaces. In the present invention, this is brought into contact with the welding bead to remove slag on the surface.

The cleaner body 1 is not limited to this tool, but may be any tool that can continuously and uniformly strike the surface of a weld bead with a light force. For example, a vibratory hammer that applies vibration or a steel grain may be used. A continuous hitting device such as a shotgun to be sprayed can also be used. The arm 4 is guided by a guide rod 6, and can be moved up and down in the axial direction of a column 7 by an elevating cylinder 5. That is, it is lowered when not in use, rises, and is used in a state where the cleaner main body 1 is in contact with the welding bead.

FIG. 3 is a partial front view showing a portion beyond the arm 4, and FIG. 4 is a partial side view of the same. As shown in FIG. 3, the arm 4 extends diagonally to support the cleaner main body 1 at a position slightly away from the center of the column.
The upper end of the holder 3 to which the cleaner main body 1 is attached is slidably suspended via a spring 31. The range of the swing angle α is approximately 45 °. Further, as shown in FIG. 4, the holder 3 is attached so as to be inclined in the front-rear direction by an angle β. This angle β corresponds to the groove shape, and may be a structure that can be adjusted depending on the application, or in the case of a bead cleaner dedicated to steel frame processing, the groove angle is generally 35 °. When it is fixed at 17.5 °, which is 1/2 of that, the cleaner body 1 is directed toward the center of the weld bead.

Since the surface of the weld bead has some irregularities, it is preferable that the cleaner main body 1 is not mounted directly on the holder 3 but is mounted via a spring 31. FIG.
(A) shows a state in which the spring 31 is extended and the cleaner main body 1 projects, and (b) shows a state in which the spring 31 is compressed and the cleaner main body 1 is immersed. The pair of guide rollers 2 is attached to the tip of a bracket 32 extending in a Y-shape from the upper end of the holder 3, and makes contact with the column material evenly in the left and right directions to swing the holder 3 in a direction perpendicular to the welding bead, and It acts to hold the cleaner body 1 close to the welding bead to an appropriate distance.

FIG. 5 is a conceptual diagram showing an example in which the outer periphery of a square steel pipe column is welded. 1A, a welding torch 22 welds an upper straight portion, and a cleaner body 1 is in contact with a lower side of the column 10 by a guide roller 2 at a lower side opposite thereto. Normally, in this state, the column member 10 is stopped, and the welding torch 22 moves horizontally as indicated by an arrow to perform welding. The bead cleaner may be moved in the same direction in conjunction with the welding robot, or may be stopped. When the welding torch 22 reaches the end of the straight portion, the columnar member 10 is rotated by the positioner as shown in FIG. During this time, the cleaner body 1 is always kept in contact with the pillar 10 by the guide roller 2 to keep the contact therewith, thereby removing the slag on the bead surface.

As described above, since this bead cleaner removes the slag on the bead surface of the previous pass by a half turn ahead of the welding torch 22, when the welding is interrupted and the bead is restarted, the bead cleaner is removed. There is no slag on the surface,
Since the weld metal is exposed, the arc starts smoothly. In addition, if the groove width is widened in the latter half pass, the slag in the corner will remain without being completely removed, but according to experiments, if about half of the bead surface slag is removed Since the arc starts, there is no problem.

In this embodiment, the rails 9 extend in the axial direction of the pillar.
Is installed, and the bead cleaner runs on this rail 9 to align with the welding joint. However, without installing the rail, a caster-type wheel that can run in a free direction may be provided on the bogie, Alternatively, it is also possible to use a vehicle in which a truck is simply placed and fixed on the floor without using any wheels. In addition, in the case of a large column combination, a plurality of welding robots may be used at the same time. However, it is effective to use the same number of bead cleaners of the present invention in combination with the welding robots.

[0021]

According to the present invention, since slag removal is reliably performed prior to welding, an arc is reliably started even after welding work is interrupted, and automatic welding by a welding robot is efficiently performed. This has the effect of improving productivity.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a side view showing an embodiment of the present invention.

FIG. 3 is a partial front view showing a part of the embodiment of the present invention.

FIG. 4 is a partial side view showing a part of the embodiment of the present invention.

FIG. 5 is a conceptual diagram showing an embodiment of the present invention.

FIG. 6 is a perspective view showing a state of steel frame processing according to the present invention.

FIG. 7 is a front view showing a welded joint at an end of a pillar according to the present invention.

FIG. 8 is a detailed view showing a groove portion of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cleaner main body 2 Guide roller 3 Holder 4 Arm 5 Elevating cylinder 6 Guide rod 7 Prop 8 Traveling trolley 9 Rail 10 Column material 21 Welding robot main body 22 Welding torch 23 Welding wire supply device 24 Nozzle cleaner 25 Robot traveling trolley 26 Positioner 27 Welding power supply Device 28 Shield gas supply device 29 Control device 31 Spring 32 Bracket

Claims (4)

(57) [Claims] An arm (4), which can be raised and lowered by a lifting mechanism (5, 6), is attached to the upper end of a column (7) erected on a carriage (8). A holder (3) to which the continuous striking device (1) is attached is swingably suspended via a spring (31), and a pair of guide rollers is attached to the tip of a Y-shaped bracket (32) extending from the upper end of the holder (3). (2) A welding bead cleaning device to which (2) is attached. 2. The welding bead cleaning device according to claim 1, wherein the continuous impact device (1) is a device in which a bundle of hard steel wires is loaded at the tip of an air hammer. 3. The welding bead cleaning device according to claim 1, wherein the continuous hitting device is mounted at an angle in accordance with a groove shape. 4. The trolley (8) runs on a rail (9) and can be positioned at a welding joint position.
The cleaning device for a weld bead according to any one of claims 1 to 3.