JP6829892B2 - Circumferential welding jig unit and circumferential welding equipment using this - Google Patents

Description

In the present invention, for example, a cylindrical body made of a metal material such as a stainless steel plate or a steel plate is abutted with a dish-shaped end plate, and the abutting portion between the body and the end plate is welded from the outside in the circumferential direction to close one end. The present invention relates to a jig unit for circumferential welding used when manufacturing a stainless steel tank, a housing, a drum can, etc., and a circumferential welding device using the jig unit.

Conventionally, a circumferential welding device for manufacturing a product such as a tank by abutting a dish-shaped end plate to one end of a cylindrical body and welding the abutting portion between the body and the end plate in the circumferential direction from the outside, for example. , Japanese Patent Application Laid-Open No. 8-224693 (see Patent Document 1) is known as a circumferential welding apparatus.

In the circumferential welding device, since the body and the end plate are welded from the outside, workability and operability are improved, but the abutting portion between the body and the end plate is not held from the inside, so that the heating is in progress. There is a problem that shrinkage and deformation occur after welding due to expansion and contraction during cooling, and the finishing accuracy of the product is significantly lowered.

On the other hand, in order to solve the above-mentioned problem, the present inventor uses a jig unit for circumferential welding in which the abutting portion between the body and the end plate is held from the inside and the circumferential welding is performed from the outside. We are developing a circumferential welding device (see Patent Document 2 and Patent Document 3).

That is, although the circumferential welding jig unit and the circumferential welding device using the same are not shown, they are an annular inner jig that can be expanded and contracted to hold the abutting portion between the body and the end plate from the inside. It is equipped with a jig unit for circumferential welding consisting of an outer jig that holds the end plate from the outside, and when the abutting part between the fuselage and the end plate is circumferentially welded from the outside, the abutting part between the body and the end plate is inside. While holding from the inside with a jig, the end plate is held by an outer jig, and in this state, the butt part of the body and the end plate is circumferentially welded from the outside with a TIG welding torch. This has the advantage that the welded portion is cooled, the thermal strain of the welded portion is suppressed, and the finishing accuracy of the product can be improved.

By the way, since the inner diameter of the body and end plate forming the tank, housing, etc. has a slight error (about 0.5 mm to 1.0 mm) in the manufacturing process, the inner circumference of the body when the body and the end plate are butted against each other. The surface and the inner peripheral surface of the end plate are not completely flush with each other.
Further, in the annular inner jig, the outer diameter of the outer peripheral surface portion in close contact with the inner peripheral surface of the body and the outer diameter of the outer peripheral surface portion in close contact with the inner peripheral surface of the end plate are formed to have the same diameter.

Therefore, when the abutting portion between the body and the end plate is held from the inside by the annular inner jig described in Patent Document 2 and Patent Document 3, the inner circumference of the body Wa is as shown in FIGS. 20A and 20B. There is a gap between the surface and the outer circumference of the inner jig 60 or between the inner peripheral surface of the end plate Wb and the outer peripheral surface of the inner jig 60, and the outer peripheral surface of the inner jig 60 is the inner peripheral surface of the body Wa or the end plate. It will not completely adhere to the outer peripheral surface of the Wb.
In FIG. 20, 61 is an outer jig and 62 is a TIG welding torch.

As a result, when the fuselage and the end plate are welded, the annular inner jig 60 cannot absorb heat reliably and satisfactorily, and the welded portion is deformed or contracted due to thermal strain, or the beads are melted down or holes are formed. There was a problem that it caused welding defects such as holes.

Further, the conventional inner jig that can be freely reduced or expanded has a complicated structure and high cost, and when the diameters of the body and the end plate are changed, the entire inner jig and the entire outer jig are changed to the body or the end plate. Therefore, a large number of inner and outer jigs must be facilitated according to the diameter of the fuselage and end plate, which requires storage space. There was also a problem in terms of cost.

Japanese Unexamined Patent Publication No. 8-224693 Japanese Patent No. 4851980 Japanese Patent No. 6222748

The present invention has been made in view of such problems, and an object of the present invention is to reliably and satisfactorily absorb heat during welding of the fuselage and end plate, significantly suppress thermal strain due to welding, and bead. It is an object of the present invention to provide a jig unit for circumferential welding, which eliminates welding defects such as melt-through and perforation, and can simplify the structure and reduce the cost, and a circumferential welding apparatus using the jig unit.

In order to achieve the above object, in the jig unit for circumferential welding according to claim 1 of the present invention, a cylindrical body and a dish-shaped end plate are butted against each other, and the abutting portion is oriented in the circumferential direction from the outside. A jig unit for circumferential welding that is used for welding and includes an inner jig unit that holds the abutting portion between the body and the end plate from the inside and an outer jig unit that holds the end plate from the outside. The inner jig unit is arranged in a ring shape at the outer peripheral position of the disk-shaped inner jig base inserted into the butt portion of the body and the end plate, and the butt of the body and the end plate. An annular inner jig that can be expanded and contracted, which is composed of a plurality of inner jig pieces that can be in close contact with the inner peripheral surface of the portion in a surface contact state, and is provided between the inner jig base and the inner jig for internal healing. It is equipped with a diameter reduction and expansion mechanism that reduces and expands the diameter of the tool, and each inner jig piece of the annular inner jig is divided into two in the axial direction of the inner jig, and one of them is the end inner peripheral surface of the end plate and the body. A movable side inner jig that can be in close contact with either one of the end inner peripheral surfaces and the other end inner peripheral surface of the end plate and the end inner peripheral surface of the fuselage. Each of the reference side internal jig pieces is linked to the diameter reduction / expansion mechanism so that the inner jig can be moved in the radial direction, and each movable side internal jig piece is connected to each internal jig. Each of the reference side inner jig pieces is supported so as to be movable in the radial direction of the inner jig, and each movable side inner jig piece is inserted between the diameter reduction / expansion mechanism and each movable side inner jig piece. It is characterized by being urged outward by the installed elastic body.

The circumferential welding jig unit according to claim 2 of the present invention has a circular pin hole in the central portion of each reference side inner jig piece in the circumferential welding jig unit according to claim 1. Along with the formation, a long hole along the radial direction of the inner jig is formed in the central portion of each movable side inner jig piece, and the pin hole of each reference side inner jig piece and each movable side inner jig piece are formed. A connecting pin is inserted into each of the elongated holes, and each movable side internal jig piece can be moved to each reference side internal jig piece in the radial direction of the internal jig, and can be swung with the connecting pin as a fulcrum. It is characterized by having a configuration that supports the above.

The circumferential welding jig unit according to claim 3 of the present invention is the circumferential welding jig unit according to claim 1 or 2, wherein the reference side jig piece and the movable side are inside. It is characterized in that a gas groove for flowing shield gas is formed on the outer peripheral surface of the jig piece and on the portion facing the butt surface of the body and the end plate to the inner peripheral surface side of the butt portion of the body and the end plate.

The circumferential welding jig unit according to claim 4 of the present invention is the reference side internal jig adjacent to the circumferential direction in the circumferential welding jig unit according to any one of claims 1 to 3. A gas escape prevention plate that can slide on the outer surface of the other reference side inner jig piece is attached to the outer surface of one of the reference side inner jig pieces, and the movable side adjacent to the circumferential direction is attached. A gas escape prevention plate that can slide on the outer surface of the other movable inner jig piece is attached to the outer surface of one of the inner jig pieces on the movable side, and the annular inner jig expands. It is characterized in that the gap between the inner jig pieces adjacent to each other in the circumferential direction is sealed by the gas escape prevention plate when the diameter is increased.

The circumferential welding jig unit according to claim 5 of the present invention is the circumferential welding jig unit according to claim 1, and the diameter reduction / expansion mechanism is internally cured at the center of the inner jig base. A rod that can be moved forward and backward along the axis of the tool base, a disk for expansion and contraction provided at the tip of the rod, and a plurality of U-shapes arranged at equal angles on one side of the inner jig base. It is slidably supported in the radial direction of the annular inner jig between the shaped slide guide, the inner jig base and each slide guide, and the inner jig on the reference side of the inner jig piece is supported at the tip on the outer side. A plurality of connecting arms to which one piece is attached, both ends of which are rotatably attached to the base end of the diameter-reducing and expanding-diameter disk and the plurality of connecting arms, respectively It is characterized in that it is provided with a plurality of link members for increasing the diameter and reducing the diameter of the annular inner jig when the diameter-expanding disk is retracted, and the connecting arms can be exchanged.

The jig unit for circumferential welding according to claim 6 of the present invention is the jig unit for circumferential welding according to claim 1, and the outer jig unit has a plurality of mounting holes concentric and predetermined. An annular shape consisting of a disk-shaped outer jig base provided at each angle of the above and a plurality of arc-shaped outer jig pieces arranged in an annular shape on one side surface of the outer jig base and capable of holding the outer peripheral surface of the end plate. It is characterized in that it is provided with an outer jig, and each piece of the outer jig of the outer jig is detachably attached to the outer jig base.

The circumferential welding jig unit according to claim 7 of the present invention is the circumferential welding jig unit according to claim 6, wherein positioning pins are provided on each of the outer jig pieces in a protruding state. Further, the positioning pins of the outer jig pieces are detachably fitted to one side surface of the outer jig base, and the positioning holes in which the outer jig pieces are arranged in an annular shape are formed concentrically. It is unique in that.

The circumferential welding device according to claim 8 of the present invention is a circumferential welding device used when a cylindrical body and a dish-shaped end plate are butted against each other and the butt portion is welded from the outside in the circumferential direction. A left-handed rotating unit provided on the base and having a left-handed rotating table that can rotate around the horizontal axis, and a right-handed unit that is provided on the base so as to face the left-handed rotating unit and can rotate around the horizontal axis. A right-handed rotating unit having a rotating table, a traveling unit provided on the base and moving at least one of the left-handed rotating unit and the right-handed rotating unit forward and backward toward the other rotating unit, and a left-handed rotating unit and right-handed rotation. The circumferential welding jig unit according to any one of claims 1 to 7, which is provided on the unit and holds the butt body and the end plate, and the butt of the body and the end plate provided on the base. It is characterized by having a welding unit equipped with a TIG welding torch that performs circumferential welding of the portion from the outside.

The circumferential welding apparatus according to claim 9 of the present invention is the circumferential welding apparatus according to claim 8, and the circumferential welding apparatus is moved to the left rotation unit side and the right rotation unit side on the base. It is characterized in that it is further provided with a table lifter that is movably provided and has a plurality of support rollers that hold the body in a horizontal position and movably in the axial direction on the upper surface.

The jig unit for circumferential welding of the present invention has a disk-shaped inner jig base, an annular inner jig that can be freely reduced and expanded in diameter, and a diameter reduction and expansion mechanism that reduces and expands the diameter of the inner jig. Each inner jig piece that is provided with a tool unit and forms an annular inner jig is divided into two in the axial direction of the inner jig, and one of them is either the end inner peripheral surface of the end plate or the end inner peripheral surface of the body. A jig piece on the reference side that can be in close contact with the jig piece, and a jig piece on the movable side that can be in close contact with either the inner peripheral surface of the end of the end plate or the inner peripheral surface of the end of the body. The tool pieces are interlocked with each other in the diameter expansion / contraction mechanism so that they can be moved in the radial direction of the inner jig base, and each movable side inner jig piece is attached to each reference side inner jig piece. As a configuration that supports the movable side inner jig piece so as to be movable in the radial direction of the above, and urges each movable side inner jig piece outward by an elastic body interposed between the diameter reduction / expansion mechanism and each movable side inner jig piece. Therefore, even if there is an error between the inner diameter of the body and the inner diameter of the end plate, each reference side internal jig piece and each movable side internal jig piece will surely adhere to the inner peripheral surface of the body and the end plate.
That is, in the jig unit for circumferential welding of the present invention, the diameter of each reference side jig piece interlocked and connected to the diameter reduction / expansion mechanism is expanded, and the core of the end plate (or body) is expanded by each reference side jig piece. Is taken out, and the gap between each movable inner jig piece and the body (or end plate) is absorbed by each movable inner jig piece that can move in the radial direction of the annular inner jig.
As a result, in the jig unit for circumferential welding of the present invention, the inner jig unit can absorb heat reliably and satisfactorily when the body and the end plate are welded, so that thermal strain due to welding can be significantly suppressed. At the same time, it is possible to prevent the beads from melting down and making holes, and it does not cause welding defects.

Further, in the jig unit for circumferential welding of the present invention, a circular pin hole is formed in the central portion of each reference side inner jig piece, and the diameter of the inner jig is formed in the central portion of each movable side inner jig piece. A long hole is formed along the direction, a connecting pin is inserted into the pin hole of each reference side internal jig piece and the long hole of each movable side internal jig piece, and each movable side internal jig piece is attached to each reference. Since each of the inner jig pieces on the side can be moved in the radial direction of the inner jig base and is supported by swinging with a connecting pin as a fulcrum, each movable inner jig piece has a yajirobe structure (balance structure). Will be exhibited, and will surely and well adhere to the inner peripheral surface of the body (or end plate).

Further, in the jig unit for circumferential welding of the present invention, the body and the end plate are located on the outer peripheral surface of each reference side inner jig piece and each movable side inner jig piece and at a position facing the abutting surface of the body and the end plate. Since a gas groove for flowing the shield gas is formed on the inner peripheral surface side of the butt portion, oxidation of the welded portion can be prevented.

Further, in the jig unit for circumferential welding of the present invention, on the outer surface of one of the reference side inner jig pieces adjacent in the circumferential direction, the other reference side inner jig piece A sliding gas escape prevention plate is attached to the outer surface of the movable side, and the outer surface of one of the movable side inner jig pieces adjacent in the circumferential direction is attached to the other movable side inner side. A sliding gas escape prevention plate is attached to the outer surface of the jig piece, and when the diameter of the annular inner jig expands, the gas escape prevention plate seals the gap between adjacent inner jig pieces in the circumferential direction. Therefore, the shield gas can flow over the entire circumference of the abutting portion between the body and the end plate, and the oxidation of the welded portion can be prevented more reliably.

Further, in the jig unit for circumferential welding of the present invention, the diameter reduction / expansion mechanism is provided on one side surface of a rod that can move forward and backward, a diameter reduction / expansion disk provided at the tip of the rod, and an inner jig base. A plurality of U-shaped slide guides arranged at equal angles are slidably supported in the radial direction of the inner jig between the inner jig base and each slide guide, and are inside the tip on the outer side. A plurality of connecting arms to which the jig piece in the reference side of the jig piece is attached, and both ends are rotatably attached to the diameter-reducing disk and the base ends of the plurality of connecting arms, respectively, and the diameter-reducing disk The body is equipped with a plurality of link members that expand the diameter of the annular inner jig when moving forward and reduce the diameter of the annular inner jig when the diameter-reducing disk retracts, and the connecting arms can be exchanged. And when the diameter of the end plate changes, it can be dealt with by replacing the connecting arm with one with a different length and replacing each inner jig piece with one with a different size, and some parts are replaced. All you have to do is do it. As a result, a large number of jig units for circumferential welding of the present invention are prepared according to the diameters of the body and the end plate as in the conventional inner jig, and the inner jig is used when the diameters of the body and the end plate are changed. Installation space and cost can be reduced without the need to replace the entire unit.

Further, in the jig unit for circumferential welding of the present invention, the outer jig unit consists of a disk-shaped outer jig base in which a plurality of mounting holes are provided concentrically and at predetermined angles, and an outer jig base. It is provided with an annular outer jig composed of a plurality of arc-shaped outer jig pieces which are arranged in an annular shape on one side surface and can hold the outer peripheral surface of the end plate, and each inner jig piece of the inner jig is externally cured. Since it is detachably attached to the tool base, if the diameters of the body and end plate change, it can be dealt with by replacing each outer jig piece with one of a different size. As a result, a large number of jig units for circumferential welding of the present invention are prepared according to the diameters of the body and the end plate like the conventional outer jigs, and the outer jigs are used when the diameters of the body and the end plate are changed. Installation space and cost can be reduced without the need to replace the entire unit.

Further, in the jig unit for circumferential welding of the present invention, positioning pins are provided on each outer jig piece forming the annular outer jig in a protruding state, and on one side surface of the outer jig base. Since the positioning pins of each outer jig piece are detachably fitted and the positioning holes in which each outer jig piece is arranged in an annular shape are formed concentrically, they are placed at a predetermined position on the outer jig base. The annular outer jig can be set accurately, easily and easily.

Since the circumferential welding apparatus of the present invention is provided with the above-mentioned circular welding jig unit, thermal strain due to welding can be significantly suppressed when welding the fuselage and the end plate, and the beads can be melted down. It can prevent perforation and does not cause welding defects.

Further, the circumferential welding device of the present invention is provided on the base so as to be movable to the left rotation unit side and the right rotation unit side, and a plurality of supports for holding the body in a horizontal posture and movably in the axial direction on the upper surface. Since the table lifter having rollers is provided, the fuselage can be easily and easily set in a predetermined position even if the diameter and length of the fuselage are different.

It is a front view of the circumferential welding apparatus using the jig unit for circumferential welding which concerns on embodiment of this invention. The inner jig unit of the circumferential welding jig unit is shown, and it is the front view in the state where the annular inner jig of the inner jig unit is reduced in diameter. Similarly, it is a side view of the state where the annular inner jig of the inner jig unit has a reduced diameter. Similarly, it is a vertical sectional side view of the annular inner jig of the inner jig unit in a reduced diameter state. Similarly, it is a front view of the state where the annular inner jig of the inner jig unit has an enlarged diameter. Similarly, it is a vertical sectional side view of the annular inner jig of the inner jig unit in a state where the diameter is expanded. It is a front view of the outer jig unit of the jig unit for circumferential welding. Similarly, it is a vertical sectional side view of the outer jig unit. The inner jig base of the inner jig unit is shown, (A) is a front view of the inner jig base, and (B) is a vertical sectional side view of the inner jig base. It is a front view of the state in which the reference side inner jig pieces of each inner jig piece forming an annular inner jig are arranged in an annular shape. The reference side inner jig piece of each inner jig piece is shown, (A) is a plan view of the reference side inner jig piece, (B) is a front view of the reference side inner jig piece, and (C) is inside the reference side. A side view of the jig piece, (D) is a vertical sectional side view of the jig piece in the reference side. It is a front view of the state in which the movable side inner jig pieces of each inner jig piece forming an annular inner jig are arranged in an annular shape. The movable inner jig piece of each inner jig piece is shown, (A) is a plan view of the movable inner jig piece, (B) is a front view of the movable inner jig piece, and (C) is the movable side inner side. A side view of the jig piece, (D) is a vertical sectional side view of the jig piece on the movable side. The relationship between the diameter-reducing disk and the link member of the diameter-reducing and expanding mechanism of the inner jig unit is shown, and (A) is a front view of a state in which a plurality of link members are rotatably attached to the diameter-reducing disk. B) is a vertical sectional side view showing a state in which a plurality of link members are rotatably attached to a diameter reduction / expansion disk. A slide guide of the diameter reduction / expansion mechanism is shown, (A) is a plan view of the slide guide, (B) is a front view of the slide guide, and (C) is a vertical sectional side view of the slide guide. The connecting arm of the diameter reduction / expansion mechanism is shown, (A) is a front view of the connecting arm, (B) is a side view of the connecting arm, and (C) is a longitudinal side view of the connecting arm. The outer jig piece forming the annular outer jig of the outer jig unit is shown, (A) is a front view of the outer jig piece, (B) is a side view of the outer jig piece, and (C) is an external jig. It is a vertical sectional side view of a tool piece, and (D) a vertical sectional side view of an outer jig piece. It is a vertical cross-sectional view of a state in which the fuselage and the end plate are circumferentially welded using a jig unit for circumferential welding. The state where the abutting portion between the body and the end plate is held from the inside by using the inner jig unit is shown, (A) is a vertical cross-sectional view when the inner diameter of the body is larger than the inner diameter of the end plate, and (B) is the inner diameter of the body. Is a vertical cross-sectional view when is smaller than the inner diameter of the end plate. A state in which the abutting portion between the body and the end plate is held from the inside using a conventional inner jig, (A) is a vertical cross-sectional view when the inner diameter of the body is larger than the inner diameter of the end plate, and (B) is a vertical cross-sectional view of the body. It is a vertical cross-sectional view when the inner diameter is smaller than the inner diameter of the end plate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a circumferential welding device 2 using the circular welding jig unit 1 according to the embodiment of the present invention, and the circumferential welding device 2 has a cylindrical shape made of a metal material such as a stainless plate or a steel plate. It is used when the body Wa and the dish-shaped end plate Wb are butted and the abutment portion between the body Wa and the end plate Wb is welded from the outside in the circumferential direction to manufacture a tank, a housing, a drum can, etc. with one end closed. Is.

That is, as shown in FIG. 1, the circumferential welding device 2 is provided on a base 4 having a plurality of adjuster bolts 3 and a left-handed rotating table that is fixedly provided on the base 4 and is rotatable around a horizontal axis. A left-handed rotating unit 6 having a fifth, a right-handed rotating unit 8 having a right-handed rotating table 7 provided on the base 4 so as to face the left-handed rotating unit 6 and rotatable around a horizontal axis, and a base 4 provided. A traveling unit 9 that moves the right-handed rotating unit 8 to the left-handed rotating unit 6 side, and a traveling unit 9 that is movably provided on the base 4 to the left-handed rotating unit 6 side and the right-handed rotating unit 8 side, and the body Wa is horizontally placed on the upper surface. A table lifter 11 having a plurality of support rollers 10 that are held in a posture and movably in the axial direction (horizontal direction in FIG. 1), and a body Wa that is provided on the left rotation unit 6 and the right rotation unit 8 and is butted against each other. A welding unit provided with a circumferential welding jig unit 1 for holding the end plate Wb and a TIG welding torch 12 provided on the base 4 for circumferentially welding the abutting portion between the body Wa and the end plate Wb from the outside. It is characterized by having 13 and.

As shown in FIG. 1, the left rotation unit 6 includes a box-shaped fixed base 15 provided with an operation panel 14 and a disk-shaped left rotation table 5 rotatably supported around a horizontal axis on the fixed base 15. A drive device (not shown) including a motor (not shown) for rotating the left turntable 5 around a horizontal axis and a transmission mechanism (not shown), which is arranged inside the fixed base 15, is provided. The left turntable 5 is arranged at the left side position on the base 4 in a posture facing the right side (right side in FIG. 1).

As shown in FIG. 1, the right-handed rotating unit 8 includes a box-shaped moving table 17 provided with an operation panel 16 and a disk-shaped right-handed rotating table 7 rotatably supported around a horizontal axis on the moving table 17. , A drive device (not shown) composed of a motor (not shown) and a transmission mechanism (not shown) that rotate the right turntable 7 around a horizontal axis, which is arranged inside the moving table 17, and the moving table 17 A fixed horizontal support frame 18, a support cylinder 19 that is rotatably and slidably penetratingly supported by the center of the moving table 17 and the right rotary table 7 and can move forward and backward toward the left rotary table 5, and a support frame. A rotary actuator 21 that is freely supported by a guide rail 20 laid on the 18 to the left rotary table 5 side and drives the support cylinder 19 to rotate, and a motor that moves the rotary actuator 21 forward and backward to the left rotary table 5 side (not shown). ), A rack (not shown), and a drive device (not shown) including a pinion gear (not shown), with the right-handed rotary table 7 facing the left side (left side of FIG. 1) and the left-handed rotary unit 6. It is arranged and fixed at the right side position on the base 4 so as to face the left turntable 5.

Further, on the front surface of the right rotation table 7 of the right rotation unit 8, pressing members 22 for pressing the end surface of the body Wa toward the left rotation table 5 are provided at equal angles.

As shown in FIG. 1, the traveling unit 9 is supported by a pair of guide rails 23 laid on the base 4 along the left-right direction and the guide rails 23 so as to travel freely, and the moving table 17 of the right-handed rotating unit 8 is supported. A traveling table 24 to be fixed, a servomotor 25 for reciprocating the traveling table 24 along the guide rail 23, and a drive device (not shown) including a ball screw mechanism (not shown) are provided. By reciprocating the 24 along the guide rail 23, the right-handed rotating unit 8 fixed to the traveling table 24 moves back and forth toward the left-handed rotating unit 6.

In the above embodiment, the traveling unit 9 moves the right-handed rotating unit 8 forward and backward toward the left-handed rotating unit 6, but in other embodiments, the traveling unit 9 rotates the left-handed rotating unit 6 clockwise. It may be moved back and forth to the unit 8 side, or both the left rotation unit 6 and the right rotation unit 8 may be moved back and forth by the traveling unit 9.

As shown in FIG. 1, the table lifter 11 is movably supported by the guide rail 23 of the traveling unit 9 toward the left rotation unit 6 side and the right rotation unit 8 side, and is supported on the upper surface of the movable table 11a. A plurality of support rollers 10 for holding the body Wa in a horizontal posture and movably in the axial direction are provided so as to be rotatable.

The circumferential welding jig unit 1 includes an inner jig unit 1 ′ that holds the butted portion of the body Wa and the end plate Wb from the inside, and an outer jig unit 1 ″ that holds the end plate Wb from the outside. The inner jig unit 1'is provided in the right rotation unit 8 and the outer jig unit 1 "is provided in the left rotation unit 6 (see FIG. 1).

As shown in FIGS. 2 to 8, the inner jig unit 1'is annular to the disk-shaped inner jig base 26 inserted into the abutting portion between the body Wa and the end plate Wb and the inner jig base 26. An annular inner jig 27 that can be expanded and contracted, and an inner jig that is arranged in a plurality of inner jig pieces 27'that can be brought into close contact with the inner peripheral surface of the abutting portion of the body Wa and the end plate Wb in a surface contact state. It is provided between the base 26 and the inner jig 27, and includes a diameter-reducing mechanism 28 for reducing and expanding the diameter of the inner jig 27.

Specifically, as shown in FIG. 9, the inner jig base 26 is formed in a disk shape by a metal material such as an aluminum alloy, and has an annular shape provided at the tip of a support cylinder 19 of the right rotation unit 8. It is concentrically fixed to the flange member 29 by a fixing bolt 30 (see FIG. 4).

Further, in the central portion of the inner jig base 26, a rod insertion hole 26a through which a rod 38 constituting the diameter reduction / expansion mechanism 28 provided at the tip of the support cylinder 19 of the right rotation unit 8 is inserted is formed so as to penetrate. Has been done. The rod 38 is composed of a piston rod of a fluid pressure cylinder (the whole is not shown) built in the tip of the support cylinder 19, and is formed in the rod insertion hole 26a of the inner jig base 26 along the axis of the inner jig base 26. It is inserted so that it can move forward and backward.

Further, on one side surface (front surface) of the inner jig base 26, a recess 26b capable of accommodating the diameter reduction / enlargement disk 39 constituting the diameter reduction / enlargement mechanism 28 is formed. The diameter-reducing and expanding disk 39 is fixed to the tip surface of the rod 38 by a fixing bolt 31.

The annular inner jig 27 is arranged in an annular shape at the outer peripheral position of the inner jig base 26, and can be brought into close contact with the inner peripheral surface of the abutting portion between the body Wa and the end plate Wb in a surface contact state, and the annular inner jig 27. It is composed of a plurality of inner jig pieces 27'movable in the radial direction of 27, and when the body Wa and the end plate Wb are butt welded, the outer peripheral surface of each inner jig piece 27'is the butt portion of the body Wa and the end plate Wb. It adheres to the inner peripheral surface of the welded part in a surface contact state, cools the welded part and suppresses thermal distortion of the welded part, prevents the beads from melting down and making holes, and also prevents the body Wa and the end plate Wb from butt. A shield gas is flowed on the inner peripheral surface side to prevent oxidation of the welded portion. In the present embodiment, the annular inner jig 27 is composed of six inner jig pieces 27'.

Further, as shown in FIGS. 2 and 4, each of the inner jig pieces 27'is divided into two in the axial direction of the annular inner jig 27, and one of the two parts is of the end plate Wb and the body Wa. A reference side jig piece 27A that can be in close contact with one of the inner peripheral surfaces of the end in a surface contact state, and the other is in close contact with one of the inner peripheral surfaces of the end of the end plate Wb and the body Wa in a surface contact state. The jig piece 27B on the movable side to be obtained is used. In the present embodiment, the outer peripheral surface of the reference side inner jig piece 27A is in close contact with the end inner peripheral surface of the end plate Wb in a surface contact state, and the outer peripheral surface of the movable side inner jig piece 27B is the end inner peripheral surface of the body Wa. It is designed to be in close contact with the jig.

Further, as shown in FIGS. 2 and 4, each of the reference side inner jig pieces 27A is interlocked with the diameter reduction / enlargement mechanism 28 and can move in the radial direction of the annular inner jig 27. Further, each of the movable inner jig pieces 27B is supported by the reference side inner jig piece 27A of each inner jig piece 27'so as to be movable in the radial direction of the annular inner jig 27, and is expanded or contracted. It is urged outward by an elastic body 32 interposed between the diameter mechanism 28 and each movable side internal jig piece 27B.

Specifically, as shown in FIGS. 10 and 11, each reference side jig piece 27A is formed in the shape of an arcuate thick-walled plate by a copper material having excellent thermal conductivity, and each reference is made. At the center of the side internal jig piece 27A, a circular pin hole 27a into which a connecting pin 33 for connecting the movable side internal jig piece 27B to the reference side internal jig piece 27A is inserted, and a reduced / enlarged diameter A recessed portion 27b into which the tip end portion of the connecting arm 41 constituting the mechanism 28 is fitted is formed.

Further, on the inner outer peripheral surface of each reference side inner jig piece 27A, the inner side surface of the reference side inner jig piece 27A (right side surface in FIG. 3) is used as the inner side surface of the movable side inner jig piece 27B (left side in FIG. 3). A step portion 27c is formed for forming a gas groove 35 through which a shield gas such as argon gas flows toward the inner peripheral surface side of the abutting portion between the body Wa and the end plate Wb when the body is brought into contact with the surface).

Further, notches 27d are provided on the outer surfaces of both ends of each reference side inner jig piece 27A. One notch 27d is for attaching a gas escape prevention plate 34 that seals a gap between adjacent inner jig pieces 27'when the diameter of the annular inner jig 27 is expanded. The other notch portion 27d is for sliding the gas escape prevention plate 34 attached to the end portion of the adjacent reference side inner jig piece 27A. The gas escape prevention plate 34 is made of a copper material having excellent thermal conductivity, and the outer peripheral surface is formed to have the same curvature as the outer peripheral surface of the reference side inner jig piece 27A.

On the other hand, as shown in FIGS. 12 and 13, each movable side internal jig piece 27B is formed in an arcuate thick-walled plate shape by a copper material having excellent thermal conductivity, and each movable side internal cure. An elongated hole 27e into which a connecting pin 33 for connecting the movable side inner jig piece 27B to the reference side inner jig piece 27A is inserted is formed in the central portion of the tool piece 27B. The elongated hole 27e matches the pin hole 27a of the reference side inner jig piece 27A and is formed along the radial direction of the annular inner jig 27.

Further, on the inner outer peripheral surface of each movable side inner jig piece 27B, the inner side surface (left side surface of FIG. 3) of the movable side inner jig piece 27B is used as the inner side surface of the reference side inner jig piece 27A (right side of FIG. 3). A step portion 27f is formed for forming a gas groove 35 through which a shield gas such as argon gas flows toward the inner peripheral surface side of the abutting portion between the body Wa and the end plate Wb when the body is brought into contact with the surface). The step portion 27f communicates with the gas passage 27g formed in the movable side inner jig piece 27B, and the shield gas supplied from the shield gas supply hose 36 connected to the inlet of the gas passage 27g passes through the gas passage 27g. It is designed to flow into the gas groove 35.

Further, notches 27h are provided on the outer surfaces of both ends of each movable side inner jig piece 27B. One notch 27h is for attaching a gas escape prevention plate 34 that seals a gap between adjacent inner jig pieces 27'when the diameter of the annular inner jig 27 is expanded. The other cutout portion 27h is for sliding the gas escape prevention plate 34 attached to the end portion of the adjacent movable side inner jig piece 27B. The gas escape prevention plate 34 is made of a copper material having excellent thermal conductivity, and the outer peripheral surface is formed to have the same curvature as the outer peripheral surface of the movable side inner jig piece 27B.

Then, each reference side internal jig piece 27A and each movable side internal jig piece 27B abut the inner side surfaces of both inner jig pieces 27A and 27B with the pin hole 27a of the reference side internal jig piece 27A. The connecting pins 33 are inserted into the elongated holes 27e of the movable side inner jig piece 27B to prevent them from coming off, respectively. As a result, the movable side inner jig piece 27B can be moved to the reference side inner jig piece 27A in the radial direction of the annular inner jig 27, and is swingably supported by the connecting pin 33 as a fulcrum. become.

Further, each movable side internal jig piece 27B is constantly urged outward by an elastic body 32 interposed between each movable side internal jig piece 27B and the diameter reduction / expansion mechanism 28 described later. The outer peripheral surface of the movable side inner jig piece 27B is located outward from the outer peripheral surface of each reference side inner jig piece 27A. That is, each movable side internal jig piece 27B is accommodated in the accommodating holes 41c formed in the plurality of connecting arms 41 constituting the expansion / contraction mechanism 28, and the tip portion protrudes from the accommodating hole 41c to form each movable side internal jig The piece 27B is constantly urged outward by the elastic body 32 that abuts on the inner peripheral surface. In the present embodiment, the elastic body 32 is composed of a compression coil spring and is provided in a pair on one connecting arm 41. Further, each movable side inner jig piece 27B moves by 2 mm in the radial direction of the annular inner jig 27.

Further, a gas escape prevention plate 34 is attached and fixed to one end of each inner jig piece 27'arranged in an annular shape by a screw 37. That is, in the notch 27d formed on the outer surface of any one of the reference side inner jig pieces 27A adjacent in the circumferential direction, the outside of the other reference side inner jig piece 27A. A gas escape prevention plate 34 that can slide on the notch 27d formed on the side surface is attached by a screw 37, and one of the movable side internal jig pieces 27B adjacent in the circumferential direction is attached. A gas escape prevention plate 34 capable of sliding on the notch 27h formed on the outer surface of the 27B is attached to the notch 27h formed on the outer surface of the other movable side inner jig piece 27B by a screw 37. As a result, when the diameter of the annular inner jig 27 is expanded, the gap between the inner jig pieces 27'adjacent in the circumferential direction can be sealed by the gas escape prevention plate 34 (see FIG. 5).

In addition, when each inner jig piece 27'is arranged in an annular shape, it is on the outer peripheral surface of each reference side inner jig piece 27A and each movable side inner jig piece 27B and faces the abutting surface of the body Wa and the end plate Wb. A gas groove 35 is formed at the location to allow the shield gas to flow toward the inner peripheral surface side of the abutting portion between the body Wa and the end plate Wb (see FIGS. 3 and 4).

As the annular inner jig 27, several types of inner jigs 27 having different diameters are prepared and can be replaced according to the inner diameters of the body Wa and the end plate Wb.

As shown in FIGS. 2, 4 to 6, the diameter reduction mechanism 28 includes a rod 38 provided at the center of the inner jig base 26 so as to be movable back and forth along the axis of the inner jig base 26, and a rod. A disk 39 for reducing and expanding the diameter provided at the tip of 38, a plurality of U-shaped slide guides 40 arranged at equal angles on one side surface (front surface) of the inner jig base 26, and an inner jig base. The annular inner jig 27 is slidably supported between the 26 and each slide guide 40 in the radial direction, and the reference side inner jig piece 27A of the inner jig piece 27'is attached to the tip portion on the outer side. The plurality of connecting arms 41 and both ends thereof are rotatably attached to the base ends of the diameter-reducing and expanding disks 39 and the plurality of connecting arms 41 via the connecting shaft 42, respectively, and when the diameter-reducing and expanding disks 39 are advanced. A plurality of link members 43 for expanding the diameter of the annular inner jig 27 and reducing the diameter of the annular inner jig 27 when the diameter-reducing disk 39 is retracted, and the connecting arms 41 can be exchanged. Is.

Specifically, the rod 38 is composed of a piston rod of a fluid pressure cylinder built in the tip of a support cylinder 19 of a right-hand rotation unit, and an axis of the inner jig base 26 is inserted into a rod insertion hole 26a of the inner jig base 26. It is inserted so that it can move forward and backward along the line.

The diameter-reducing disk 39 is formed of a metal material such as an aluminum alloy, and bifurcated portions 39a for connecting the base end portions of the connecting arm 41 are provided at equal angles on the outer peripheral edge portion. (See FIG. 14). The diameter-reducing disk 39 is fixed to the tip surface of the rod 38 in a vertical position by a fixing bolt 31 (see FIG. 4). In the present embodiment, six bifurcated portions 39a are formed at equal angles on the outer peripheral edge portion of the diameter expansion / contraction disk 39.

The slide guide 40 is formed in a U shape by a metal material such as an aluminum alloy, and is arranged on one side surface (front surface) of the inner jig base 26 concentrically and at equal angles, and a plurality of fixed slide guides 40 are fixed. It is fixed to the front surface of the inner jig base 26 by bolts 44 (see FIGS. 5 and 15). In this embodiment, six slide guides 40 are arranged on the front surface of the inner jig base 26.

The connecting arm 41 is formed of a metal material such as an aluminum alloy, and a bifurcated portion 41a connected to a bifurcated portion 39a of a diameter-reducing disk 39 is formed at a base end portion, and a tip portion thereof is formed. Is formed with a pin hole 41b that matches the pin hole 27a of the reference side inner jig piece 27A (see FIG. 16). Further, at the tip of the connecting arm 41, an accommodating hole 41c for accommodating the elastic body 32 for urging the movable inner jig piece 27B of the inner jig piece 27'outward is provided in the longitudinal direction of the connecting arm 41. Two are formed along the above (see FIGS. 4 and 16). Further, the connecting arm 41 is slidably supported at its base end portion between the inner jig base 26 and each slide guide 40, and slides in the radial direction of the annular inner jig 27. .. In addition, the tip of the connecting arm 41 is fitted into the recess 27b of the reference side inner jig piece 27A of the inner jig piece 27', and is inside the reference side of the inner jig piece 27' by the connecting pin 33. It is connected to the jig piece 27A. In this embodiment, six connecting arms 41 are used.

As the connecting arm 41, several types of connecting arms 41 having different lengths are prepared and can be replaced according to the inner diameters of the body Wa and the end plate Wb.

The link member 43 is formed of a metal material such as an aluminum alloy, and one end thereof is rotatably connected to the bifurcated portion 39a of the diameter reduction / expansion disk 39 via a connecting shaft 42, and the other end. A portion is rotatably connected to the bifurcated portion 41a of the connecting arm 41 via a connecting shaft 42 (see FIGS. 2, 4 and 5). As a result, the diameter-reducing disk 39 and the connecting arm 41 are interlocked and connected via the link member 43. In this embodiment, six link members 43 are used.

Therefore, according to the diameter reduction / expansion mechanism 28, when the rod 38 is advanced to push the diameter reduction / expansion disk 39 forward, the link member 43 slides the connecting arm 41 outward of the inner jig base 26. When the annular inner jig 27 moves and expands in diameter (see FIGS. 5 and 6), and the rod 38 is retracted and the diameter reduction / expansion disk 39 is pulled back to the inner jig base 26 side, the link member The connecting arm 41 slides inward of the inner jig base 26 by the 43 to reduce the diameter of the annular inner jig 27 (see FIGS. 2 and 4).

As shown in FIGS. 7 and 8, the outer jig unit 1 ″ is annularly arranged on one side surface of the disk-shaped outer jig base 45 and the outer jig base 45 to hold the outer peripheral surface of the end plate Wb. An annular outer jig 46 composed of a plurality of arcuate outer jig pieces 46'is provided, and each outer jig piece 46'of the outer jig 46 is detachably attached to the outer jig base 45. In the present embodiment, the annular outer jig 46 is composed of six outer jig pieces 46'.

Specifically, as shown in FIGS. 7 and 8, the outer jig base 45 includes an outer jig base plate 45'formed on an annular disk made of a metal material such as an aluminum alloy and a metal such as an aluminum alloy. The outer jig base 45 ″ is provided with an outer jig base middle plate 45 ″ which is formed in a disk shape by a material and is fitted to the center of the outer jig base plate 45 ′ and fixed by a fixing bolt 47. On one side surface (front surface), a mounting hole 45a (female screw hole) for mounting each outer jig piece 46'of the outer jig 46 and a positioning hole 45b for positioning each outer jig piece 46' Are concentric and are provided at predetermined angles.

On the other hand, as shown in FIGS. 7 and 17, the annular outer jig 46 is composed of six outer jig pieces 46'formed in the shape of an arcuate thick-walled plate made of a copper material having excellent thermal conductivity. On the surface of each outer jig piece 46'that faces the outer jig base 45, a pair of positioning pins 46a that are detachably inserted into the positioning holes 45a formed in the outer jig base 45 are provided in a protruding state. ing. Further, each outer jig piece 46'is provided with a pair of bolt insertion holes 46b that match the mounting holes 45a formed in the outer jig base 45.

As the annular outer jig 46, several types of annular outer jigs 46 having different radii of curvature and sizes are prepared, and can be replaced according to the outer diameters of the body Wa and the end plate Wb.

Thus, in the outer jig unit 1 ″, each outer jig piece 46 ′ is arranged in an annular shape on the same circumference of the outer jig base 45, and the positioning pin 46a of each outer jig piece 46 ′ is externally cured. It is assembled by inserting it into the positioning hole 45b of the tool base 45 to position each outer jig piece 46', and then fixing each outer jig piece 46'to the outer jig base 45 with a fixing bolt 48 in this state. ..

Further, the outer jig unit 1 ″ is attached to the front surface (right side surface in FIG. 1) of the left rotation unit 6 by a plurality of attachment shafts 49 so as to face each other, and the annular outer jig 46 Is facing the inner jig unit 1'side.

As shown in FIG. 1, the welding unit 13 causes a shield gas such as argon gas to flow from the tip portion, and a TIG welding torch 12 to which a tungsten electrode rod 12a is inserted and a TIG welding torch 12 are vertically and horizontally A torch support unit 50 that can be freely adjusted to move in the direction and the front-rear direction, a touch panel 51 that sets welding conditions and the like to display welding current, welding speed, etc., and a main operation panel 53 provided with various switches 52 for setting. , A power supply device for welding (not shown), a gas cylinder for welding (not shown), etc. are provided, and the TIG welding torch 12 is used for the body when the butt portion of the body Wa and the end plate Wb is circumferentially welded from the outside. The torch 12 for TIG welding moves to a position near the abutting portion between Wa and the end plate Wb, and while the shield gas flows from the tip portion at this position, the abutting portion between the fuselage Wa and the end plate Wb that rotates about the axis is shielded gas. It is designed to be circularly welded by arc in the atmosphere of.

The TIG welding torch 12 is provided with a narrowing nozzle inside the shield nozzle so that the shield gas is divided into the outside and the inside and the inner shield gas is ejected at a higher speed than the outer shield gas. 12 is used. As the TIG welding torch 12, those described in Japanese Patent No. 5602974 and Japanese Patent No. 5887445 are used.

Next, a case where the cylindrical body Wa and the dish-shaped end plate Wb are circumferentially welded by the circumferential welding device 2 using the circumferential welding jig unit 1 described above will be described.

The body Wa and the end plate Wb are made of stainless steel. Welding conditions such as welding current, arc length, rotation speed of the body Wa and end plate Wb, and supply amount of shield gas are set to optimum conditions according to the material and thickness of the body Wa and end plate Wb. Of course there is.

First, the end plate Wb is fitted into the annular outer jig 46 of the outer jig unit 1 ″, and the body Wa is set on the support roller 10 on the table 11a of the table lifter 11 and held in a horizontal position. The table lifter 11 is raised so that one end of the body Wa (the end facing the left rotation unit 6) faces the end of the end plate Wb.

Next, the body Wa is manually slid toward the end plate Wb so that the end portion of the body Wa is brought into contact with the end portion of the end plate Wb, and in this state, the right rotation unit 8 is advanced to press the right rotation table 7. The body Wa is pressed toward the end plate Wb by the member, and the end portion of the body Wa is brought into close contact with the end portion of the end plate Wb.

Subsequently, the support cylinder 19 is advanced and the annular inner jig 27 of the inner jig unit 1'attached to the tip thereof is positioned inside the abutting portion between the body Wa and the end plate Wb, and in this state, the inner jig The annular inner jig 27 of the unit 1'is expanded in diameter by the diameter-reducing and expanding mechanism 28 to be brought into close contact with the vicinity of the inner peripheral surface of the abutting portion between the body Wa and the end plate Wb in a surface contact state.

At this time, in the annular inner jig 27, each inner jig piece 27'is divided into two in the axial direction of the inner jig 27, and one of them can be brought into close contact with the inner peripheral surface of the end portion of the end plate Wb. One piece 27A and the other piece 27B on the movable side that can be in close contact with the inner peripheral surface of the end of the body Wa, and each reference side inner jig piece 27A is interlocked and connected to the diameter reduction / expansion mechanism 28. The jig base 26 can be moved in the radial direction, and each movable side inner jig piece 27B is supported by each reference side inner jig piece 27A so as to be movable in the radial direction of the inner jig 27. Since the movable side inner jig piece 27B is configured to be urged outward by an elastic body 32 interposed between the movable side inner jig piece 27B and each movable side inner jig piece 27B, FIG. 19A is shown. As shown in (B), even if there is an error between the inner diameter of the body Wa and the inner diameter of the end plate Wb, each reference side internal jig piece 27A and each movable side internal jig piece 27B are inside the body Wa and the end plate Wb. It will surely adhere to the peripheral surface.

When the butt portion is held from the inside by the inner jig unit 1'in the state where the body Wa and the end plate Wb are abutted, the table lifter 11 is lowered, and in this state, the left rotation unit 6 and the right rotation unit 8 And the welding unit 13 operates to weld the abutting portion between the body Wa and the end plate Wb from the outside in the circumferential direction.

That is, the body Wa and the end plate Wb are synchronously rotated in the same direction at a constant speed by the left rotation table 5, the right rotation table 7, and the support cylinder 19, and the body Wa and the end plate are rotated by the shield gas supply hose 36 and the gas passage 27g. Shield gas is supplied to the inner peripheral surface side of the butt portion of Wb, and in this state, the TIG welding torch 12 of the welding equipment unit moves forward and downward to generate an arc, and the butt portion of the body Wa and the end plate Wb is outward. Circumferential welding from.

At this time, since the annular inner jig 27 of the inner jig unit 1'has expanded in diameter and is in close contact with the inner peripheral surface of the abutting portion of the body Wa and the end plate Wb in a surface contact state, when performing circumferential welding. The annular inner jig 27 cools the welded portion, significantly suppresses thermal strain of the welded portion, prevents bead melting and perforation, and does not cause welding defects. ..

When the circumferential welding of the body Wa and the end plate Wb is completed, the rotation of the left rotary table 5, the right rotary table 7 and the support cylinder 19 is stopped, the arc and the shield gas are stopped, and the TIG of the welding unit 13 is stopped. The welding torch 12 rises and falls back to its original position.

After that, the table lifter 11 rises to hold the body Wa and the end plate Wb welded around the circumference, the diameter of the annular inner jig 27 is reduced, and the clockwise rotation unit 8 is retracted to retract the body Wa and the inner jig from inside the body Wa. Pull out unit 1'.

Finally, the end plate Wb is removed from the outer jig 46, and the table lifter 11 is lowered to take out the body Wa and the end plate Wb that are circumferentially welded from the table lifter 11.

In the above embodiment, of the reference side inner jig piece 27A and the movable side inner jig piece 27B forming each inner jig piece 27'of the annular inner jig 27, the reference side inner jig piece 27' The 27A is brought into close contact with the inner peripheral surface of the end portion of the end plate Wb, and the movable side inner jig piece 27B is brought into close contact with the inner peripheral surface of the end portion of the body Wa. However, in other embodiments, the reference side inner jig The piece 27A may be brought into close contact with the inner peripheral surface of the end portion of the body Wa, and the movable side inner jig piece 27B may be brought into close contact with the inner peripheral surface of the end portion of the end plate Wb.

1 is a jig unit for circumferential welding, 1'is an inner jig unit, 1 ″ is an outer jig unit, 2 is a circumferential welding device, 4 is a base, 5 is a left rotation table, and 6 is a left rotation unit. 7 is a right-handed rotating table, 8 is a right-handed rotating unit, 9 is a traveling unit, 10 is a support roller, 11 is a table lifter, 12 is a TIG welding torch, 13 is a welding unit, 26 is an inner jig base, and 27 is an annular shape. Inner jig, 27'is an inner jig piece, 27A is a reference side inner jig piece, 27B is a movable side inner jig piece, 27a is a pin hole, 27e is a long hole, 28 is a diameter reduction / expansion mechanism, and 33 is a connection. Pin, 34 is gas escape prevention plate, 35 is gas groove, 38 is rod, 39 is disk for expansion and contraction, 40 is slide guide, 41 is connecting arm, 43 is link member, 45 is external jig base, 45b is The positioning hole, 46 is an annular outer jig, 46'is an outer jig piece, 46a is a positioning pin, Wa is a body, and Wb is a mirror plate.

Claims (9)

It is used when a cylindrical body (Wa) and a dish-shaped end plate (Wb) are butted and the butt portion is welded in the circumferential direction from the outside, and the butt portion between the body (Wa) and the end plate (Wb) is used. With an inner jig unit (1') for holding the end plate (Wb) from the inside and an outer jig unit (1 ″) for holding the end plate (Wb) from the outside. The inner jig unit (1') includes a disk-shaped inner jig base (26) and an inner jig base (26) that are inserted inside the abutting portion between the body (Wa) and the end plate (Wb). 26) The diameter reduction self is composed of a plurality of inner jig pieces (27') which are arranged in an annular shape at the outer peripheral position and can be brought into close contact with the inner peripheral surface of the butted portion of the body (Wa) and the end plate (Wb) in a surface contact state. A diameter reduction mechanism (28) provided between the existing annular inner jig (27) and the inner jig base (26) and the inner jig (27) to reduce or increase the diameter of the inner jig (27). ), And each inner jig piece (27') of the annular inner jig (27) is divided into two in the axial direction of the inner jig (27), and one of them is the inner circumference of the end of the end plate (Wb). A reference side jig piece (27A) that can be in close contact with either the surface or the inner peripheral surface of the end of the body (Wa), and the other is the inner peripheral surface of the end of the end plate (Wb) and the end of the body (Wa). A movable side inner jig piece (27B) that can be in close contact with either one of the inner peripheral surfaces of the part is used, and each reference side inner jig piece (27A) is interlocked and connected to a diameter reduction / expansion mechanism (28) for internal healing. The tool (27) can be moved in the radial direction, and each movable side internal jig piece (27B) is internally cured by the reference side internal jig piece (27A) of each internal jig piece (27'). While supporting the tool (27) so as to be movable in the radial direction, each movable side internal jig piece (27B) is inserted between the diameter reduction / expansion mechanism (28) and each movable side internal jig piece (27B). A jig unit for circumferential welding, characterized in that it is urged outward by an elastic body (32) provided. A circular pin hole (27A) is formed in the central portion of each reference side internal jig piece (27A), and the diameter of the internal jig (27) is formed in the central portion of each movable side internal jig piece (27B). A long hole (27e) is formed along the direction, and a connecting pin is formed in the pin hole (27A) of each reference side internal jig piece (27A) and the long hole (27e) of each movable side internal jig piece (27B). (33) is inserted, and each movable side internal jig piece (27B) can be moved to each reference side internal jig piece (27A) in the radial direction of the internal jig (27), and the connecting pin (27B). The jig unit for circumferential welding according to claim 1, wherein the jig unit is configured to swingably support the 33) as a fulcrum. On the outer peripheral surface of each reference side internal jig piece (27A) and each movable side internal jig piece (27B) and at a position facing the abutting surface of the body (Wa) and the end plate (Wb), the body (Wa) and The jig unit for circumferential welding according to claim 1 or 2, wherein a gas groove (35) for flowing a shield gas is formed on the inner peripheral surface side of the abutting portion of the end plate (Wb). Slide on the outer surface of one of the reference side inner jig pieces (27A) adjacent to the circumferential direction, and on the outer surface of the other reference side inner jig piece (27A). A movable gas escape prevention plate (34) is attached, and one of the movable side internal jig pieces (27B) adjacent in the circumferential direction is attached to the outer surface of the movable side internal jig piece (27B), and the other. A sliding gas escape prevention plate 34 is attached to the outer surface of the movable inner jig piece (27B), and when the annular inner jig (27) expands in diameter, the gas escape prevention plate (34) makes a circle. The jig unit for circumferential welding according to any one of claims 1 to 3, wherein the gap between the inner jig pieces (27') adjacent to each other in the circumferential direction is sealed. The diameter reduction mechanism (28) includes a rod (38) provided at the center of the inner jig base (26) so as to be movable back and forth along the axis of the inner jig base (26), and the rod (38). A disk for reducing and expanding the diameter (39) provided at the tip, a plurality of U-shaped slide guides (40) arranged at equal angles on one side surface of the inner jig base (26), and an inner jig. It is slidably supported in the radial direction of the annular inner jig (27) between the base (26) and each slide guide (40), and the reference of the inner jig piece (27') is attached to the outer tip. A plurality of connecting arms (41) to which a side jig piece (27A) is attached, and both ends are rotatably attached to the base ends of a diameter-reducing disk (39) and a plurality of connecting arms (41). The annular inner jig (27) is expanded in diameter when the reduction / expansion disk (39) is advanced, and the annular inner jig (27) is reduced in diameter when the reduction / expansion disk (39) is retracted. The jig unit for circumferential welding according to claim 1, further comprising a link member (43) of the above, and the connecting arms (41) can be exchanged. The outer jig unit (1 ″) has a disk-shaped outer jig base (45) having a plurality of mounting holes concentrically provided at predetermined angles, and one side surface of the outer jig base (45). The outer jig (46) is provided with an annular outer jig (46) which is arranged in an annular shape and is composed of a plurality of arc-shaped outer jig pieces (46') capable of holding the outer peripheral surface of the end plate (Wb). The jig unit for circumferential welding according to claim 1, wherein each outer jig piece (46') of) is detachably attached to an outer jig base (45). A positioning pin (46a) is provided on each of the outer jig pieces (46') in a protruding state, and each outer jig piece (46') is provided on one side surface of the outer jig base (45). Item 6 is characterized in that the positioning pin (46a) is detachably fitted and the positioning holes (45b) in which the outer jig pieces (46') are arranged in an annular shape are formed concentrically. The described jig unit for circumferential welding. A circumferential welding device (2) used for abutting a cylindrical body (Wa) and a dish-shaped end plate (Wb) and welding the butt portion in the circumferential direction from the outside, and is a base (4). ), A left-handed rotating unit (6) having a left-handed rotating table (5) that can rotate around a horizontal axis, and a base (4) facing a left-handed rotating unit (6). At least one of a right-handed rotating unit (8) having a right-handed rotating table (7) rotatable around a horizontal axis and a left-handed rotating unit (6) or a right-handed rotating unit (8) provided on a base (4). A traveling unit (9) that moves one rotating unit forward and backward toward the other rotating unit, and a body (Wa) and a mirror plate (Wb) that are provided on the left rotating unit (6) and the right rotating unit (8) and are butted against each other. The circumferential welding jig unit (1) according to any one of claims 1 to 7, and the body (Wa) and end plate (Wb) provided on the base (4). A circumferential welding device including a welding unit (13) provided with a TIG welding torch (12) for circumferentially welding the butt portion from the outside. The circumferential welding device (2) is provided on the base (4) so as to be movable toward the left rotation unit (6) side and the right rotation unit (8) side, and the body (Wa) is placed on the upper surface in a horizontal posture. The circumferential welding apparatus according to claim 8, further comprising a table lifter (11) having a plurality of support rollers (10) that are movably held in the axial direction.

Images