JPH0929430A - Device for welding inside of tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate accurate welding even to a slender tube body extended to the vertical direction. SOLUTION: An upper turning-drive block 17 is inserted into the inner part of the slender tube body 12 extended to the vertical direction, and a turning center shaft extended to the vertical direction at the lower end of a lower elevating/ lowering-drive block 18 fitted to the lower part of the upper turningdrive block 17 is inserted to a shaft-holder of a working reference block 49 pre-inserted into the bottom part of the tube body 12. In this situation, the lower elevating/lowering-drive block 18 is turned in the horizontal direction to the upper turning-drive block 17 and an elevating/lowering body 35 is vertically moved to the lower elevating/lowering-drive block 18 and the welding of the inner part of the tube body 12 is executed by using a welding torch while advancing/retreating the welding torch in the diameter direction of the tube body 12 to the elevating/lowering body 35.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pipe welding apparatus.

[0002]

2. Description of the Related Art Currently, a vertical heat exchanger is used in each field.

FIG. 10 shows an example of a vertical heat exchanger 1, in which an inner pipe body 4 is inserted and arranged in a primary medium flow path 3 formed inside an outer pipe body 2, A primary medium inlet 5 is formed at the lower end of the body 2, a primary medium outlet 6 is formed near the upper end of the outer tube 2, and a plurality of secondary medium inlet headers 7 are formed at the upper end of the outer tube 2. The secondary medium inlet header 7 and the lower end portion of the inner tube body 4 are connected to each other by a large number of heat transfer tubes 8 spirally arranged inside the primary medium flow path 3.

Incidentally, 9 is a primary medium, 10 is a secondary medium, and 11
Is the secondary medium outlet.

Then, the primary medium 9 is supplied from the primary medium inlet 5 formed at the lower end portion of the outer tubular body 2, the primary medium 9 is passed through the primary medium flow path 3, and then the outer tubular body is It is taken out from the primary medium outlet 6 formed in the vicinity of the upper end of 2.

At the same time, the secondary medium 10 is supplied from the secondary medium inlet header 7 provided at the upper end of the outer tubular body 2, and the secondary medium 10 is spirally arranged inside the primary medium flow path 3. Through a large number of heat transfer tubes 8 and sent to the inner tube body 4,
After passing the secondary medium 10 from the lower end side to the upper end side of the inner pipe body 4, it is taken out from the secondary medium outlet 11 at the upper end of the inner pipe body 4.

As a result, heat is exchanged between the primary medium 9 and the secondary medium 10.

[0008]

However, the vertical heat exchanger 1 has the following problems.

That is, since it is expected that the heat transfer tubes 8 of the vertical type will be worn or damaged during use, the number of heat transfer tubes 8 to be installed is set to heat exchange. Designed so that the heat transfer tubes 8 are manufactured in a larger number than necessary, and when the heat transfer tubes 8 are worn or damaged due to long-term operation, the damaged heat transfer tubes 8 can be closed to continue the operation. Has been done.

However, in the case of the vertical heat exchanger 1, the inner tube body 4 has a diameter of about 20 to 30 cm and a length of about 10.
Since it is extremely thin and long, the connection between the heat transfer tube 8 and the lower end of the inner tube body 4 cannot be reached by the operator, and such narrow space is repaired. Since there was no device that could do so, the heat transfer tube 8 that actually suffered damage etc.
Could not be blocked.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an in-pipe welding apparatus capable of accurately performing welding or the like even on a vertically elongated tubular body. I am trying.

[0012]

DISCLOSURE OF THE INVENTION The present invention relates to an upper swing drive block which can be inserted into an elongated tubular body extending in the vertical direction, and a shaft holder of a work reference block which is inserted and arranged at the bottom of the tubular body. A lower elevating drive block that has an insertable vertical axis extending in the up-down direction in its lower part, and is attached to the lower part of the upper swing drive block so as to be rotatable in the horizontal direction about the central axis of rotation. The present invention relates to an in-pipe welding apparatus, comprising an elevating body which is attached to a lower elevating drive block so as to be able to ascend and descend, and a welding torch which is attached to the elevating body so as to be able to move in and out in the diameter direction of the pipe body. .

According to the above means, the following effects can be obtained.

An upper turning drive block is inserted into a slender tubular body extending in the vertical direction, and a turning central shaft extending in the vertical direction at a lower end of a lower lifting drive block attached to a lower portion of the upper turning drive block is provided with a tubular body. Insert it into the shaft holder of the work reference block that is previously inserted and arranged at the bottom of the.

In this state, the lower lifting drive block is horizontally rotated with respect to the upper turning drive block, the lifting body is moved up and down with respect to the lower lifting drive block, and the welding torch is moved in and out of the tubular body with respect to the lifting body. At the same time, the welding torch is used to weld the inside of the pipe body.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 9 show an example of an embodiment of the present invention.

In the figure, reference numeral 12 denotes a vertically extending pipe body to be inspected or repaired. In the present embodiment, an inner pipe of a vertical heat exchanger 1 as shown in FIG. The case of the body 4 is illustrated, and the work target portion is a plurality of branch pipes 13 (heat transfer tubes 8) in the lower part of the pipe body 12.
Is a connection portion 14 with.

As shown in FIG. 1, various working units 15 for inspecting and repairing the inside of the pipe body 12 are provided.
The in-pipe working device 16 including the above is suspended and supported, and the in-pipe working device 16 is composed of an upper turning drive block 17 and a lower lifting drive block 18 as described in detail below.

As shown in FIGS. 1 and 3, the upper swing drive block 17 is provided at the upper end with a suspending tool 19 for securing the wire of a crane or the like (not shown), and the upper swing drive block 17 is vertically moved. A circumferential positioning motor 22 is fixedly installed in the middle part, and a rotary shaft 20 connected to the upper end of the lower elevating drive block 18 is rotatable via a speed reducer 21.

Further, as shown in FIGS. 3 and 6, the entire upper turning drive block 17 is positioned on the inner peripheral surface of the pipe body 12 at the upper position of the circumferential positioning motor 22 in the upper turning drive block 17. Upper clamp mechanism 23 for fixing
The upper clamp mechanism 23 is provided with a cam member 26 that is moved up and down by the air cylinder 24 at the axial center portion of the intermediate base plate 25, and a sliding member that is opened in three radial directions centering on the cam member 26. A moving hole 27, a sliding member 28 slidably accommodated in each sliding hole 27, a rubber shoe 29 attached to the outer end of each sliding member 28, and an inner end of each sliding member 28. Guide roller 30 and
The sliding member 28 is constituted by a leaf spring 31 for urging the sliding member 28 toward the cam member 26 side, and the rubber shoes 29 are moved in and out of the sliding hole 27 by the vertical movement of the cam member 26 with respect to the intermediate base plate 25. I am trying to get it.

A turning origin 32 is provided at an appropriate position in the circumferential direction on the upper surface of the lower lift drive block 18, and a turning origin 32 is provided at an appropriate position in the circumferential direction on the lower surface of the upper turning drive block 17 so as to face the turning origin 32. A rotation origin sensor 33 capable of detecting the above is provided, and the rotation origin detection mechanism 31 configured by the rotation origin 32 and the rotation origin sensor 33 allows the upper swing drive block to the lower lift drive block 18. The relative rotation origin position of 17 can be detected.

On the other hand, as shown in FIGS. 2 and 4, the lower elevating / lowering drive block 18 includes an elevating / lowering body 35 for holding a working unit 15, which will be described later.
A plurality of (four in the figure) lifting guide shafts 38 arranged between the upper base plate 36 and the lower base plate 37.
It is designed to be guided vertically along the.

In addition, at a position above the upper base plate 36, a screw rod 40 screwed into the nut 39 can be projected and retracted downward by rotationally driving the nut 39. Motor 41
The lower end of the screw rod 40 penetrates through the central portion of the upper base plate 36 and is rotatably connected to the upper end of the elevating body 35.

Further, the upper base plate 36 includes
An intermediate stage clamp mechanism 42 for fixing the entire position of the lower lift drive block 18 to the inner peripheral surface of the tubular body 12 is provided. As shown in FIGS. 4 and 7, the intermediate stage clamp mechanism 42 includes an upper base plate 36. A pair of cylinder portions 43 open in opposite radial directions, and both cylinder portions 43
It is composed of a piston portion 44 slidably fitted inside and a rubber shoe 45 attached to the outer surface of both piston portions 44 so that the piston portion 44 can be moved in and out by air pressure.

Further, a rotation center shaft 46 is provided so as to project downward at the center of the lower surface of the lower base plate 37, and a plurality of positions in the circumferential direction in the vertical middle portion of the rotation center shaft 46 and At the lower end, a steel ball 47 for rotation guide,
48 are provided for rolling freely.

Here, the rotation center shaft 46 is the tube body 12.
9 is mounted in advance on the shaft holder 50 of the work reference block 49 as shown in FIG. 9 and is rotatably supported by a shaft. Axis 4
6, a lock mechanism 51 for fixing the shaft holder 50 of the work reference block 49 is provided.

That is, as shown in FIG. 5, the rotation center shaft 46 is provided inside the outer cylinder 52 by an outer cylinder 52 having the steel balls 47 and 48 and an air cylinder 53 mounted on the lower base plate 37 side. It has a double structure consisting of a lock shaft 54 which is moved up and down by. The lock shaft 54
Small diameter portions 55 and 56 are formed at the vertical middle portion and the lower end, respectively, and at the positions corresponding to the small diameter portions 55 and 56 of the lock shaft 54 on the outer cylinder 52 side, the respective small diameter portions 55. , 56 to surround a plurality of steel balls 57, 58
Is held movably outward in the radial direction, and
The steel balls 5 are provided at positions on the inner peripheral surface of the shaft holder 50 of the work reference block 49 facing the steel balls 57 and 58.
A plurality of vertical grooves 59 and a ring-shaped horizontal groove 60 are formed so that 7, 58 can be fitted, and the lock shaft 54 is pushed down by the air cylinder 53 so that the steel balls 57, 58 are placed in the shaft holder 50. By fitting in the vertical groove 59 and the horizontal groove 60 on the peripheral surface, the rotation center shaft 46 can be fixed to the shaft holder 50 of the work reference block 49 in the rotational direction and the vertical direction, respectively.

The shaft holder 50 of the work reference block 49 is engaged with a vertical guide groove 62 via a key 61 so that it can be moved up and down within a range defined by the vertical guide groove 62. is there.

Further, the work reference block 49 is provided with a lower stage clamp mechanism 63 for fixing the entire position of the work reference block 49 to the inner peripheral surface of the pipe body 12. The lower stage clamp mechanism 63 is shown in FIG. As shown in FIG. 5, FIG. 8 and FIG. 9, sliding holes 64 opened in three radial directions centering on the shaft holder 50, and sliding members 65 slidably accommodated in the respective sliding holes 64. , A rubber shoe 66 attached to the outer end of each sliding member 65, a guide roller 67 attached to the inner end of each sliding member 65, and urging each sliding member 65 toward the shaft holder 50 side. It is composed of a leaf spring 68 and a cam recess 69 formed in the lower part of the shaft holder 50, and the rubber shoes 66 can be moved in and out by moving the shaft holder 50 up and down with respect to the work reference block 49.

A rotation origin 70 is provided at an appropriate circumferential position on the upper surface of the work reference block 49, and a rotation origin 70 is provided at an appropriate circumferential position on the lower surface of the lower lifting drive block 18. Origin sensor 71 capable of detecting
The rotation origin detection mechanism 72 including the rotation origin 70 and the rotation origin sensor 71 detects the rotation origin position of the lower lift drive block 18 relative to the work reference block 49. Is ready to go.

Further, a peephole 73 penetrating in the vertical direction is formed at an appropriate position of the work reference block 49.
Also, the lower base plate 3 of the lower lift drive block 18
7 shows the tubular body 1 through the peep hole 73 when the rotation origin 70 and the rotation origin sensor 71 face each other.
2 A reference line 7 previously formed at an appropriate position in the circumferential direction on the bottom.
A reference line confirmation camera 94 is provided so that 4 can be photographed.

In the figure, 75 is each air cylinder 24, 5
3 and lower lift drive block 18 middle clamp mechanism 42
Hose joints for working air used in, etc., 76 cable joints for power systems and signal systems, 77 and 78 solenoid valves for various systems, 79 an upper turning drive block 17 for relative rotation
Side and the lower lifting drive block 18 side are electrically connected to each other, and 80 is a power connection mechanism for relatively rotating the upper turning drive block 17 side and the lower lifting drive block 18 side for operating air and the like. 8 rotary joints for making connections
Reference numeral 1 is a signal line reduction device, and 82 is a surveillance camera control device.

In contrast to the in-pipe working device 16 having the above structure, the present invention further includes a welding unit 83 as the working unit 15 on the lifting body 35. If there is enough space, as shown in Figs. 1 and 2,
The lifting body 35 may be provided with the plug insertion unit 84.

As shown in FIG. 5, the welding unit 83 includes a welding torch 87 on a support member 86 that moves along a guide portion 85 extending in the diametrical direction of the tubular body 12, and a welding torch 87 is provided on the upper surface of the support member 86. A nut 89 screwed to a rotatable screw rod 88 extending parallel to the guide portion 85 is fixed to the screw rod 88, and the lifting body 3 is attached to the screw rod 88.
The torque of the advancing / retreating motor 90 disposed at an appropriate position of No. 5 can be transmitted through the bevel gears 91 and 92, and the welding unit 83 is moved by the relative movement of the nut 89 by the rotational driving of the screw rod 88. Are being moved back and forth.

Further, a work monitoring camera 93 is provided at an appropriate position of the elevating body 35 so that the vicinity of the tip of the welding unit 83 can be photographed.

Reference numeral 95 is a plug to be welded, which is inserted in the connecting portion 14 between the pipe 12 and the branch pipe 13.

Next, the operation will be described.

The operation of closing the connection portion 14 between the lower position in the pipe body 12 and the branch pipe 13 is performed in the following procedure.

First, the work reference block 49 is inserted into the pipe 12.
And the work reference block 49 is positioned.
Next, the position of the branch pipe 13 to be occluded is indexed with the work reference block 49 as a reference, and the connection portion 14 of the indexed branch pipe 13 with the tube body 12 is bored to expand the hole diameter and perform boring. The polished portion and its periphery are surface-polished. Then, the plug 9 for closing the boring connection portion 14
5 is inserted and the inserted plug 95 is welded to the pipe body 12. Further, the welded portion is subjected to a flaw inspection, and if there is no abnormality as a result of the flaw inspection, a pressure resistance test is performed. If the pressure resistance test is passed, the work reference block 49 is taken out from the pipe body 12, and a series of operations is completed.

Among the above-mentioned operations, the insertion positioning and indexing of the operation reference block 49 are performed by using the in-pipe working device 16 with the position detecting unit, and the boring is performed by using the in-pipe working device 16 with the boring unit. For the polishing, the in-pipe working device 16 having the surface polishing unit attached thereto is used. For inserting the plug 95, the in-pipe working device 16 having the plug inserting unit 84 attached is used. For welding, the in-pipe working device according to the present invention having the welding unit 83 attached. 16, the flaw detection inspection is performed by using the in-pipe working device 16 having the flaw detection unit, and the pressure resistance test and the removal of the work reference block 49 are performed by using the in-pipe working device 16 having the pressure resistance test unit.

Therefore, in the present invention, after inserting the plug 95 by the in-pipe working device 16 having the plug inserting unit 84, the in-pipe working device 16 having the plug inserting unit 84 is removed from the pipe body 12 by using a crane or the like (not shown). Withdraw.

At this time, as shown in FIG. 9, the shaft holder 50 of the work reference block 49 is replaced by the upper turning drive block 1.
7 and the lower lifting drive block 18 are pushed down, and the guide roller 67 of each sliding member 65 is pushed out from the cam recess 69 at the lower part of the shaft holder 50, so that each sliding member 65 is pushed.
Since the rubber shoe 66 is pressed against the inner peripheral surface of the pipe body 12 and the work reference block 49 is fixed in position on the inner peripheral surface of the pipe body 12, The block 49 will be left at the bottom of the tube 12.

When the in-pipe working device 16 having the plug insertion unit 84 attached is pulled out, the in-pipe working device 16 of the present invention having the welding unit 83 attached thereto is replaced with
Lift using a crane (not shown).

At this time, regarding the upper clamp mechanism 23 provided in the upper turning drive block 17, the air cylinder 2
4, the cam member 26 is pulled up to pull in the respective sliding members 28 inward, and the respective rubber shoes 29 are kept in an unclamped state in which they do not contact the inner peripheral surface of the tubular body 12, and the middle stage provided in the lower lifting drive block 18 With regard to the clamp mechanism 42, each piston part 44 is pneumatically driven to the cylinder part
The rubber shoes 45 are pulled in and the clamps are released so that the rubber shoes 45 do not come into contact with the inner peripheral surface of the tubular body 12.

Next, the in-pipe working device 16 is suspended in the pipe body 12, and the rotation center shaft 46 at the lower end of the lower base plate 37 in the lower lift drive block 18 is set to the shaft of the work reference block 49 left in the pipe body 12. It is inserted into the holder 50.

Then, the cam member 26 is pulled down by the air cylinder 24 in the upper clamp mechanism 23, the sliding members 28 are projected outward, and the rubber shoes 29 are attached to the tubular body 1.
(2) The upper turning drive block 17 is pressed against the inner peripheral surface to fix the position of the upper turning drive block 17 on the inner peripheral surface of the tube body 12.

In this state, the upper turning drive block 1
By driving the circumferential positioning motor 22 provided in 7, the lower lifting / lowering drive block 18 is rotated, and the work reference block 49 and the turning origin 70 and the turning origin sensor 71 in the lower lifting / lowering drive block 18 are moved. Confront.

Further, the upper clamp mechanism 23 is unclamped, and instead, each piston portion 44 of the middle clamp mechanism 42 is projected from the inside of the cylinder portion 43 by air pressure to press each rubber shoe 45 against the inner peripheral surface of the pipe body 12. By fixing the lower lifting drive block 18 on the inner peripheral surface of the tube body 12 and driving the circumferential positioning motor 22 of the upper turning drive block 17, the upper turning drive block 18 is rotated upward. Drive block 17
Is relatively rotated to make the rotation origin 32 and the rotation origin sensor 33 in the lower lift drive block 18 and the upper swing drive block 17 face each other.

After the work reference block 49, the lower lifting drive block 18 and the upper turning drive block 17 have been aligned in this way, the upper turning drive block 17 is again placed on the inner peripheral surface of the pipe body 12 by the upper clamping mechanism 23 of the upper stage. Fix the position.

In such a state of the in-pipe working device 16, the upper swing drive block 17, the lower lift drive block 18, and the work reference block 49 are rotated relative to their origins (rotation origins 32 and 70). The moving origin sensors 33 and 71 are in a state of being aligned with each other (positions facing each other), and also in a state of being aligned with a predetermined rotation origin position (the reference line 74 position) with respect to the tube body 12, so to speak. It is a reference posture when performing positioning in the up-down direction and the circumferential direction of the pipe body 12 between the connecting portion 14 of each branch pipe 13 and the working unit 15 inside.

The in-pipe working device 16 is the working unit 1
As shown in FIG. 5, when both the plug insertion unit 84 and the welding unit 83 are provided, as shown in FIGS.
The above work is unnecessary.

After that, the middle clamp mechanism 42 is released from the clamp, and the circumferential positioning motor 22 is driven to rotate the lower lifting drive block 18 to move the working unit 15 in the circumferential direction of the pipe 12. Further, by driving the vertical positioning motor 41, the elevating body 35 is moved up and down to move the working unit 15 in the vertical direction, and the plug 9
The working unit 15 is positioned at the position of the connecting portion 14 of the branch pipe 13 into which 5 is inserted.

When the positioning of the work unit 15 is completed as described above, the work by the work unit 15 is started. Particularly in the case of the present embodiment, the work unit 15 is the welding unit 83. Therefore, the lifting body 35
Screw rod 88 by the advancing / retreating motor 90 provided for
The welding torch 87 is advanced by the relative movement of the nut 89 by adjusting the distance between the welding torch 87 and the welding portion with respect to the plug 95 and the pipe body 12,
At the same time, by driving the circumferential positioning motor 22, the lower lifting drive block 18 is rotated to move the welding torch 87 in the circumferential direction of the pipe body 12, and by driving the vertical positioning motor 41, the lifting body is lifted. While the welding torch 87 is moved up and down by moving 35 up and down, the periphery of the plug 95 and the connecting portion 14 of the pipe body 12 are welded.

Further, when the work by the welding unit 83 is completed, the welding torch 87 is retracted, and the upper clamp mechanism 23 and the middle clamp mechanism 42 are unclamped, and the upper swing drive block 17 and the lower lift drive block 18 are placed. Is lifted and pulled out from the pipe body 12, and only the work reference block 49 is left at the bottom of the pipe body 12.

Subsequently, the in-pipe working device 16 equipped with a flaw detection unit for carrying out the next work is hung on the pipe body 12, and the rotation center shaft 46 at the lower end of the lower lifting drive block 18 is hung up.
The work reference block 49 left at the bottom of the pipe body 12.
It is fitted into the shaft holder 50, the flaw detection unit is positioned in the same manner as described above, and the flaw detection inspection of the welded portion is performed by the flaw detection unit.

When all the working steps are completed while the pipe working device 16 is replaced at any time, the work reference block 49 is attached to the pipe body 1 using the pipe working device 16 inserted last.
Remove from inside 2.

Therefore, according to the above-described embodiment, the in-pipe working device 16 provided with the welding unit 83 is inserted into the extremely slender pipe body 12, and the work reference block left at the bottom of the pipe body 12. Accurately plug 95 based on 49
Welding work can be performed.

The present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0060]

According to the above-described in-pipe welding apparatus of the present invention, it is possible to obtain an excellent effect that it is possible to perform welding with high precision even on a slender tubular body extending in the vertical direction.

[Brief description of drawings]

FIG. 1 is a schematic overall perspective view of an example of an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a lower portion of FIG.

FIG. 3 is a side sectional view of the upper portion of FIG.

FIG. 4 is a side sectional view of the lower portion of FIG.

5 is a side cross-sectional view of the lower portion of FIG.

FIG. 6 is a view taken in the direction of arrows VI-VI in FIG. 3;

7 is a view taken along the line VII-VII in FIG.

FIG. 8 is a view on arrow VIII-VIII in FIG.

FIG. 9 is a partial lateral cross-sectional view showing a state of a work reference block left on the bottom of the tubular body.

FIG. 10 is a side sectional view of a vertical heat exchanger.

[Explanation of symbols]

 12 Tube 17 Upper Swiveling Drive Block 18 Lower Elevating Drive Block 35 Elevating Body 46 Rotation Center Axis 49 Work Reference Block 50 Axis Holder 87 Welding Torch

Claims (1)

[Claims] 1. An upper slewing drive block that can be inserted into an elongated tubular body extending in the vertical direction, and a vertically extending rotary block that can be inserted into a shaft holder of a work reference block inserted and arranged at the bottom of the tubular body. It has a moving center axis in its lower part, and it can be moved up and down to a lower lifting drive block that is attached to the lower part of the upper turning drive block so that it can rotate horizontally around the rotation center axis. An in-pipe welding apparatus, comprising: an elevating body attached to the elevating body;