JPS6150072B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circumferential TIG automatic welding device that enables butt welding of pipes in a narrow space.

When butt welding pipes together in a narrow space, for example when butt welding pipes together in a group of pipes that are arranged close to each other,
Conventionally, the butt portions were formed into a V-shaped or U-shaped groove and welded manually or automatically by adding filler metal. In such cases, the distance between the pipes that can be constructed (the size of the space around the pipes) is approximately 25 to 30 mm when using automatic welding, and more than 20 mm when using manual welding.
If it is less than mm, it becomes impossible to perform work using conventional welding methods. In other words, if you try to move the welding rod or filler metal along the circumferential surface of the tube, the surrounding tubes will get in the way, making it impossible to do so, and it will also be difficult to monitor the welding arc, making it impossible to respond immediately to problems that occur. It will disappear.

The present invention aims to enable butt welding in confined spaces. In order to achieve this objective, in the present invention, a ring-shaped filler metal is temporarily attached to the abutting portion of the tubes, and the electrode is rotated while being monitored along the filler metal. In this method, a two-split energizing ring is rotatably attached to the inside of a two-split main body that surrounds the peripheral surface of the tube, an electrode is held in the energizing ring, and the main body is rotated according to the locus of the electrode that rotates as the energizing ring rotates. The circumferential TIG automatic welding device is characterized in that the annular portion is made of a transparent material, and further includes two split adapter rings on both sides of the main body that come into close contact with the tube circumferential surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an automatic welding apparatus according to the present invention will be described in detail below with reference to the drawings.

As shown in FIGS. 1A and 1B, when butt welding of pipes 1 to each other in a group of pipes in which a large number of pipes 1 are arranged adjacent to each other is performed using the automatic welding device of the present invention, the butt welding is performed as a preliminary operation. A ring-shaped filler metal 2 is temporarily attached to the part. Details of an automatic welding device for welding the tubes 1 together by melting the abutting portions of the filler metal 2 and the tube 1 are shown in FIGS. 2 to 5. Note that FIG. 2 shows a case where the curved pipe 1 is butt welded.

The main body 3 surrounding the butted tube 1 consists of two halves of blocks 4a and 4b and blocks 5a and 5b. There is a gap between blocks 4a, 4b and blocks 5a, 5b, and adjacent blocks 4a, 4b are spaced apart from each other.
a, 5a and 4b, 5b are connected to each other by connecting plates 6 at a plurality of locations on their circumferences. As shown in FIG. 4, which shows a cross section taken along the - arrow in FIG. 2, the mating surfaces of the lower blocks 4b and 5b have
A female screw member 7 is embedded, and the upper block 4
By screwing the tip of the fixing screw shaft 8 passing through a and 5a into the female threaded member 7,
4b and 5a and 5b are combined, and the main body 3
become one. Reference numeral 9 denotes a retaining ring provided on the fixed screw shaft 8, which prevents the fixed screw shaft 8 from coming off from the block 4a or 5a. Also, each block 4 of the main body 3
Two split adapter rings 10a, 10b forming a circle slightly smaller than the outer diameter of the tube 1 are attached to the outer end surfaces of the tubes a, 4b, 5a, 5b, respectively. Heat-resistant rubber (for example, fluorocarbon rubber) 11 is baked on the inner periphery of the adapter rings 10a and 10b, and the tube 1
When the main body 3 is assembled surrounding the adapter ring 10
The heat-resistant rubber 11 of a and 10b is in close contact with the circumferential surface of the tube 1,
The body 3 is held on the tube 1.

Two ring gears 12a, 12b are rotatably fitted inside the blocks 4a, 4b of the main body 3. Each ring gear 12a, 12b has two ceramic rings 13a, 1 as an insulating material.
The current-carrying rings 14a and 14b are each connected to each other by bolts via 3b. energizing ring 14a,
Heat-resistant insulating rings 15a, 15b are provided between the rings 14b and the blocks 4a, 4b, and act to insulate the current-carrying rings 14a, 14b from the blocks 4a, 4b, as well as to block the heat generated in the welded parts. An electrode holding portion 14 is provided on one of the two divided current-carrying rings 14a and 14b, extending in the direction of the generatrix of the current-carrying ring 14a. This electrode holding part 14 is located between the blocks 4a, 4b and 5a, 5b, and the tungsten electrode 16 is fixed here with a set screw 17. In other words, the situation from the electrode 16 can be monitored from the outside of the main body 3. However, since shielding gas is supplied around the electrode 16, adjacent blocks 4a are
Two pieces of quartz glass 18a, 18b are sandwiched between 5a, 4b, and 5b with heat-resistant rubber 19 interposed therebetween. In the drawings, 20a and 20b are heat-resistant insulating rings provided inside the blocks 5a and 5b.

The electrode 16 is pivoted along the filler metal 2, for which a drive 21 is provided on the block 4a. Reference numeral 22 designates a gear box installed on the block 4a, in which is supported by a pin 24 a two-stage gear 23 in which one gear meshes with the ring gears 12a and 12b.
The other gear is connected to a pinion 27 on the motor 26 side via an intermediate gear 25. motor 2
6 drives the current-carrying ring 14 through the gear train.
The electrode 16 is rotated together with a and 14b. The intermediate gear 25 is supported by a clutch pin 28 and pressurized by a compression spring 30 via a pusher 29 so as to maintain a position in which it meshes with the two-stage gear 23 and pinion 27. By the way, the clutch pin 28 has a locking pin 31 facing in the vertical direction, and as shown in FIG. 3, which is a cross-sectional view of FIG. A knob 34 is attached. Holding the knob 34, push the clutch pin 2 until the locking pin 31 comes out outside the clutch cover 33.
8 is pulled out and rotated 90 degrees, the locking pin 31 hits the outer surface of the clutch cover 33 and the clutch pin 28 will not return, and the intermediate gear 25 will be disengaged from the pinion 27. In other words, the ring gears 12a, 12b can rotate freely.

In addition, the fifth point representing the V arrow view in FIG. 3 and FIG.
As shown in the figure, the block 4a has a power supply device 35.
is provided. Insulating block 36 is attached to block 4a.
is attached, and the conductor 38 and female threaded portion 39 of the power supply nipple 37 are fixed to this insulating block 36 by a holding plate 40. A current-carrying plate 41 is pressed into the female threaded portion 39 by a pressure screw 42 . A copper stranded wire 43 and a current-carrying brush 44 are brazed to the current-carrying plate 41, and the tip of the brush 44 is pressed by a compression spring 45 against the surface of the rotating current-carrying rings 14a, 14b. In the drawing,
46 is a heat-resistant insulating bushing. On the other hand, seal gas passages 47a and 47 are provided in the blocks 5a and 5b.
b are formed, and these passages 47a, 47b
communicates with the inside of the main body 3 via filter rings 48a and 48b made of sintered metal (mesh size 20-100μ). A shield gas nipple 49 is screwed into the block 5a in connection with the passage 47a. An air-cooled torch cable 50 through which shielding gas passes is connected to the power supply nipple 37, and an insulated nylon tube 51 that guides only the shielding gas is connected to the power supply nipple 37, the tip of which is connected to the shield gas nipple 49. is connected to. That is, the current flows through the conductor 38 of the power supply nipple 37 to the power supply section, and the shielding gas passes through the nylon tube 51, passes through the nipple 49, and passes through the passage 47a.
47b, filtering 48a, 48b
is supplied to the welding area through. Note that a gas vent hole 52 is provided in the adapter ring 10a.

Next, a welding procedure using the apparatus having the above configuration will be explained.

Adapter ring 10 according to the diameter of the pipe to be welded 1 and the radius of curvature R if the pipe 1 is a curved pipe.
a, 10b to each block 4a, 4b and 5a, 5
A half ring gear 12b with one of the two halves of the ceramic ring 13b and an energizing ring 14b attached is rotated and inserted into the blocks 4b and 5b which are fixed to the outer surface of the tube 1 and connected by the connecting plate 6, The tube is rotated half a turn around the pipe 1 to be rewelded from the interval δ.

Next, similar ceramic ring 13a, electrode 1
The ring gear 12a, which is integrally split in half with the current-carrying ring 14a fixed to which the ring gear 6 is fixed, is fixed together.
Slide it into the block 4a of the integrated blocks 4a, 5a, align it with the end faces of the blocks 4b, 5b that have already been wrapped around the back side of the tube 1, and then tighten the blocks 4a, 5a and 4 with the fixing screw shaft 8.
b and 5b are combined to assemble the main body 3. At this time, the electrode 16 is positioned relative to the filler metal 2.

In this case, pull the knob 34 of the clutch pin 28 in the drive device 21 to the left,
If the clutch cover 33 is rotated 90 degrees so that it rides on the outer surface of the clutch cover 33 and stops, the intermediate gear 25 will come off from the pinion 27 and the ring gears 12a, 12
b can be rotated freely, making installation easier.

Next, shielding gas is supplied through the insulating nylon tube 51. The shielding gas that has entered the sealing gas passage 47a passes through the filter rings 48a, 4.
8b, the passages 47a and 47b are filled in the circumferential direction, and when the pressure reaches a certain level, the shielding gas is discharged through the filter rings 48a and 48b, so that the shielding gas becomes an even and almost completely laminar flow, which is good for the welding part. Create an atmosphere.

Next, when the knob 34 is turned to align the locking pin 31 with the vertical groove 32 of the clutch cover 33, the clutch pin 28 will return to its original position due to the spring force of the compression spring 30, and the intermediate gear 25 will be connected not only to the second gear 23 but also to the second gear 23. A state in which the pinion 27 also meshes with the pinion 27, that is, a state in which the energizing rings 14a and 14b can be rotated is achieved.

After that, turn on the power switch and start energizing.
An arc is generated from the tip of the tungsten electrode 16 to melt the abutting ends of the filler metal 2 and the tube 1, and the energizing ring 1 is driven by the motor 26.
The electrode 16 is rotated together with 4a and 14b to advance welding. In this case, since the quartz glass tubes 18a and 18b are used in the intermediate portion of the main body 3, arc monitoring becomes easy.

In addition, in preparation for overheating of the main body due to continuous use for a long period of time, a water cooling structure may be provided by providing a water cooling hole in the main body 3 and connecting a water hose. It is also possible to use a double-shaft type motor, detect the rotational speed using a photoelectric switch, etc., and provide feedback to the position control (current, speed) for all-position welding.

As explained above based on one embodiment, according to the automatic welding device according to the present invention, welding is performed by moving the electrode along the ring-shaped filler metal provided at the butt part of the pipes, so the wire supply is reduced. This eliminates the need for butt welding of pipes in confined spaces. Furthermore, since the arc can be monitored through a transparent material such as a quartz glass tube, it is possible to improve the quality of welded parts and to quickly respond to troubles.

[Brief explanation of the drawing]

FIGS. 1A and 1B are a perspective view and a cross-sectional view showing how a ring-shaped filler metal is provided at the abutting portion of the tube,
2 is a longitudinal cross-sectional view of an embodiment of the present invention, FIG. 3 is a cross-sectional view of the embodiment shown in FIG. 2, FIG. 4 is a half-sectional view taken along the - arrow in FIG. 2, and FIG. is a view taken along the arrow in FIG. In the drawings, 1 is a tube, 2 is a filler metal, 3 is a main body, 4a, 4b, 5a, 5b are blocks, and 10
a, 10b are adapter rings, 12a, 12b are ring gears, 14a, 14b are energizing rings, 16
18a and 18b are tungsten electrodes, 21 is a drive device, 35 is a power supply device, 37 is a power supply nipple, and 44 is a current-carrying brush.

Claims (1)

[Claims] 1. A two-split energizing ring is rotatably attached to the inside of a two-split main body that surrounds the peripheral surface of the tube, and an electrode is held in the energizing ring, and the annular shape of the main body corresponds to the locus of the electrode that rotates due to the rotation of the energizing ring. A circumferential TIG automatic welding device, characterized in that the part is made of a transparent material, and further, two split adapter rings are provided on both sides of the main body so as to be in close contact with the circumferential surface of the pipe.