JPH09253888A - Pipe inner clamp device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe inner clamp device free from any chipped parts in a backing of a weld zone, and capable of improving the welding quality. SOLUTION: A pipe inner clamp device 1 fixes two pipes 3, 7 to be butted to each other at end parts from the inner side of the pipes. The pipe inner clamp device is provided with a plurality of clamp pads 51 which can be pressed against the inner surface of the butted end parts of two pipes 3, 7, are split in the circumferential direction and also used as backings, and cotter pads 131 which are inserted in the clearances between the split clamp pads 51 as a part of the backings to the inner surface of the pipe end parts. In the inner clamp device, the clamp pads 51 (or coffer pads 131) which are also used as the backings are present over the whole circumference of the pipe end face butted parts (the back side of the root gap) without clearance. Thus, the permanent welding can be continuously achieved in the clamped condition, and the working efficiency is also improved. The welding quality is also improved because no chipped parts are present in the backings.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe inner clamp device for abutting the ends of two pipes to be welded and fixing them from the inside of the pipes during joint welding of pipes in pipeline construction. Especially, there is a clamp pad (including cotter pad) that is also used as a backing metal that is pressed against the inner surface of the pipe over the entire circumference, and there is no defect in the backing of the welded part. Regarding the device.

[0002]

2. Description of the Related Art When drawing a pipeline for transporting gas, oil, etc., pipes (generally made of steel) are welded one after another and connected. At this time, it is necessary for the quality control of the welding work to properly align (center) the two pipe end faces to be welded and firmly fix them at the connecting portion of the pipes. The pipe inner clamp device is used for that purpose.

The main body of the inner clamp device is inserted into the inner surface of the pipe. And using some kind of clamp mechanism,
By pressing an arc-shaped clamp pad against the inner surfaces of the two butted pipes in the vicinity of the pipe ends, both pipes are aligned and the pipes are firmly fixed. However, in the conventional inner clamp device, there is a gap between the plurality of divided clamp pads,
There was nothing to fill this. This gap is the space behind the root gap between the pipe end faces,
In the first layer of welding, the weld metal was burned down, and the backside was not well obtained, resulting in poor welding quality.

On the other hand, there is also a method in which after the pipe is centered and fixed using a clamp device, the pipe is temporarily tack-welded in that state, and then a backing metal separate from the clamp device is attached. This method did not cause deterioration of welding quality due to defective backing. However, clamp → temporary →
The work and the time required were more than doubled because the backing metal installation and the work involved three steps. Further, during the main welding, it is necessary to take appropriate measures for the tack welded portion.

[0005]

The conventional inner clamp device has the following problems. Weld quality deterioration due to insufficient backing. The labor and work time required for mounting the backing metal separately from the clamps was great. In particular, in the case of a large-diameter pipe, the weight of the inner clamp device and the pipe also becomes heavy, so it was necessary to mechanize various operations for centering the pipe, setting the gap, and fixing the pipe.

According to the present invention, there is no defect in the backing of the welded portion,
An object of the present invention is to provide a pipe inner clamp device capable of improving welding quality. Furthermore, it is possible to provide a pipe inner clamp device that can easily and properly perform centering of pipes and setting intervals (route gaps) between pipe ends over the entire circumference of the pipe end face, and can reduce labor for that. To aim.

[0007]

In order to solve the above problems, a pipe inner clamp device of the present invention is a pipe inner clamp device for fixing two pipes, which are butted at their ends, from the inside of the pipe. hand;
It can be pressed against the inner surface of the butt ends of the two pipes,
A clamp pad that also serves as a backing metal and is divided into several pieces in the circumferential direction, and a cotter pad that is inserted into a gap between the divided clamp pads and serves as a part of the backing material to the inner surface of the pipe end. And are provided.

In the inner clamp device of the present invention, there is a clamp pad (or cotter pad) also serving as a backing metal over the entire circumference of the pipe end face abutting portion (back of the root gap) without any gap. Therefore, the main welding can be continuously performed with the clamped, and the work efficiency is improved. Moreover, since there is no defect in the backing, the welding quality is improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A pipe inner clamp device according to one aspect of the present invention is a circumferentially dispersed pipe which can be projected between both end faces of the above-mentioned two pipes and can be drawn in from the end faces to the inner diameter side. A plurality of spacers that are provided in the same manner, and a means that draws the spacers in the depth direction of the one pipe so that each of the plurality of spacers abuts an end surface of one of the two pipes. When,
Is further provided.

Means for mechanizing the root gap setting spacer is incorporated in the inner clamp device, and means for bringing the spacer into contact with the end surface of one pipe (generally, the existing pipe) is also provided. Therefore, the labor required for setting the gap is significantly reduced.

In the inner clamp device of this aspect, the cotter pad is reciprocated between a position where the cotter pad is inserted into a gap between the divided clamp pads and a position where the cotter pad is removed from the gap. And the spacer also reciprocates between the position inserted into the gap between the divided clamp pads and the position removed from the gap. It is configured so that the cotter pad,
From the final stage of pipe clamp (after centering and root gap setting) to the first layer welding of the pipe butt joint, it is located at the insertion position and forms a part of the entire backing metal. It is preferably located at the insertion position.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 and 2 are schematic views conceptually showing a pipe inner clamp device and its operation (a → i) according to an embodiment of the present invention. 1 (a) to 1 (e), a pipe inner clamp device 1 and an existing pipe 3 of this embodiment are shown.
Are shown. 2 (f) to 2 (i), the existing pipe 3 on the left side and the joint pipe 7 on the right side have their pipe end faces abutted to each other in the central portion of the drawing. The existing pipe 3 is a pipe already laid at one end of the pipeline. The joint pipe 7 is beyond the existing pipe 3 (right side)
This is the pipe to be welded.

At the portion where the pipeline curves, the existing pipe 3 and the joint pipe 7 are connected with their axes slightly inclined. This inclination is absorbed by slightly inclining the end faces of both pipes 3 and 7 with respect to the axis of each pipe. On the end face of the pipe, a groove slope 3-1,
7-1 and root surfaces 3-2 and 7-2 which are steep surfaces
The V-shaped groove made of is processed (see also FIG. 6). After fixing the pipe with the inner clamp device, the groove portion is welded by the welding torch 5-1 of the welder head 5 as shown in FIG. 1 (i). The head 5 travels in the circumferential direction on a guide rail 6 wound around the outer circumference of the existing pipe 3.

An outline of the inner clamp device 1 of this embodiment will be described with reference to FIG. The inner clamp device 1 has the following operation parts for acting on the pipes 3 and 7 to be clamped. (1) Main clamp 50: The main clamp 50 is present on the outer circumference at about 1/3 from the front of the inner clamp device 1 (on the right side of the drawing) and over almost the entire circumference. In addition, in this specification, FIG.
The right side (joint pipe 7 side) to the front, the left side (existing pipe 3
The side) is called the back. The main clamp 50 is pressed against the inner surfaces of the abutting portions of the two pipes to be connected to perform centering and fixing of the two pipes, and is the most important operating portion of the inner clamp device. As shown in detail in FIG. 4, the clamp pad 51 of the main clamp 50.
Is divided into three in the circumferential direction, and exists on the entire circumference except for the gap between them. The main clamp 50 will be driven in the radial direction by the wedge 117, the main clamp cylinder 111 and the like shown in FIG.

(2) Rear Clamp 20: The inner clamp device 1 is provided at three locations on the outer surface of the central portion of the right and left sides, all of which are distributed about 120 ° over the entire circumference. This rear clamp 20
Is the rear clamp cylinder 21 and the rear clamp pad 2
Drive 3 in the radial direction. When the rear clamp pad 23 projects outward and is pressed against the inner surface of the pipe 3,
The main frame 11 (see also FIG. 3) of the inner clamp device 1 is fixed to the existing pipe 3.

(3) Front Clamp 60: The inner clamp device 1 is divided into 3 parts on the outer surface of the front part by about 120 ° on the entire circumference.
There are two places. In this front clamp 60, the front clamp cylinder 61 drives the front clamp pad 63 in the radial direction. When the front clamp pad 63 projects outward and is pressed against the inner surface of the pipe 7, the main frame 11 (see also FIG. 3) of the inner clamp device 1 is fixed to the joint pipe 7.

(4) Drive wheel 25: Two rows (see FIG. 10) are provided in the circumferential direction on the rear lower surface of the rear clamp 20. The drive wheel 25 is driven by a hydraulic motor 26 via a belt 27. When the drive wheel 25 rotates, the inner clamp device 1 moves in the pipe from side to side in the drawing. When the inner clamp device becomes larger (in this embodiment, for 900A pipe, own weight 1,600 kg), the inner clamp device is moved left and right by hand (pulling out and pushing in).
Because it becomes difficult, it is hydraulically driven. However, since the speed by this drive wheel 25 is slow (2-5 m / min),
When moving to the next clamping place (12m right for one pipe) after the completion of the clamping work, pull the chain 68 (hanging on the front handle 67) with a chain block or the like to move the inner clamp device 1. Become. The driven wheel 26 is on the front lower surface of the rear clamp 20. The driven wheel 28 is an idle roller.

(5) Cotter device 130: Three parts are provided on the outer surface of the front side of the driven wheel 26 at 120 ° distribution over the entire circumference. The cotter device 130 includes a cotter pad 131.
In the circumferential direction of the main clamp pad 51 divided into three in the circumferential direction (spacers 150-1, 2, 3 in FIG. 4).
(Where it can be seen) is inserted diagonally. The outer surface (see FIG. 9) of the cotter pad 131 becomes a part of the entire circumference backing metal during welding. Incidentally, this cotter device 130
The spacer device 150, which will be described below, can be moved back and forth, and only when it fulfills its role, the main clamp pad 51 can be moved.
It will be in the same position (in the same front-back direction).

(6) Spacer device 150: cotter device 1
On the outer surface of the front side of 30, facing the cotter device 130, they are provided at three locations allotted about 120 ° on the entire circumference. As shown in FIG. 2 (f), the spacer 151 of the spacer device 150 is inserted between the existing pipe 3 end face root portion 3-2 and the joint pipe 7 end face root portion 7-2 and welded. It is used for setting the root gap of the groove.

Next, the operation of the pipe inner clamp device of the embodiment shown in FIG. 1 will be described. In FIG. 1A, the clamping work at the previous clamping position is completed, and the existing pipe 3 is pulled by the chain 68 and is moving to the right. That is, the inner surface between the end portions of the existing pipe 3'on the left side of the existing pipe 3 and the existing pipe 3 (inside the welding bead 2).
After being clamped by the main clamp pad 51, the clamp pad 51 serves as a backing metal for the first layer welding of the welding bead 2 and then moves to the next clamping work position. At this time, the main clamp 50, the rear clamp 20, the front clamp 60, the cotter device 130, and the spacer device 150 are all retracted toward the inner diameter side.

Proceeding to FIG. 1B, the inner clamp device 1 has just reached the right end of the existing pipe 3.
The main clamp pad 5 is provided near the outside of the end surface of the existing pipe 3.
The front and rear alignment of the inner clamp device 1 is performed so that the center line 1 and the spacer 151 come. Then, the spacer 151 is projected in the outer diameter direction.

1C, the drive wheels 25 are driven to retract the inner clamp device 1 in the depth direction of the existing pipe 3. Thereby, the inner clamp device 1 is
It moves and stops until at least one of the spacers 151 at three locations in the circumferential direction contacts the root portion 3-2 of the existing pipe 3. At this time, the three spacers 15
There is no guarantee that all 1 are in contact with the root part 3-2. This is because there is a tilt of the end surface of the existing pipe 3 with respect to the pipe axis and a tilt of the inner clamp device 1 itself.

As shown in FIG. 1D, the rear clamp 20 is actuated and the main body of the inner clamp device 1 is installed in the existing pipe 3.
It is fixed on the inner surface. Proceeding to FIG. 1 (e), the spacer 151 is pulled toward the main frame 11 side fixed to the existing pipe 3 using the end face matching cylinder 31. The end face matching cylinders 31 are provided at three places in the circumferential direction,
The spacers 151 are moved inward until all the spacers 151 come into contact with the end surface of the existing pipe 3. At this time, since the swingable and slidable spherical bearing 40 (FIG. 3) exists between the main frame 11 and the spacer 151, the spacer 151 is pressed so as to follow the end surface of the existing pipe 3, and the spacer 151 is pressed at three positions. All the spacers 151 are route parts 3 of the end face of the existing pipe 3
Contact 2

Proceeding to FIG. 2 (f), the connecting pipe 7 is set. That is, the inner surface of the left end portion of the joint pipe 7 is fitted to the right side of the outer peripheral portion of the clamp pad 51. The joint pipe 7 end face route portion 7-2 is in contact with the right side face of the spacer 151. Such work is done manually. 2 (g), when the joint pipe 7 is set, the front clamp 60 is operated to press the front clamp pad 63 against the inner surface of the joint pipe 7 so that the inner clamp device 1 is attached to the joint pipe 7. Even fixed.

Proceeding to FIG. 2 (h), the clamp pad 51
Is projected outward and pressed against the inner surfaces of the ends of the existing pipe 3 and the joint pipe 7. By this, both pipes 3 and 7
However, they are fixed with their axes aligned and the root gap in the normal size. Next, the spacer 151 is pulled inward. At this time, the clamp pad 51 remains pressed against the inner surfaces of the pipes 3 and 7. Subsequently, the spacer 151 is retracted forward, and then the cotter pad 13
Advance 1 The cotter pad 131 moves diagonally outward and is pressed against the inner surfaces of the ends of the pipes 3 and 7. The cotter pad 131 fills the circumferential gap of the main clamp pad 51, and completes a backing metal having no gap over the entire circumference.

Proceeding to FIG. 2 (i), butt welding is performed from the outer surface of the pipe using the welding head 5 and the torch 5-1.
Both pipes 3 and 7 are connected. When the first layer welding is finished and the backing is no longer needed, pull in the clamp pad 51, the cotter pad 131, and other clamps inside,
The inner clamp device 1 is made free, and the inner clamp device 1 is moved to the next work point (the right end portion of the joint pipe 7). Hereinafter, the same work / operation is repeated.

A specific structure of the inner clamp device will be described. FIG. 3 is a sectional view specifically showing an example of the internal structure of the inner clamp device conceptually shown in FIGS. 1 and 2. FIG. 3 is a partial cross-sectional view showing a clamp pad portion of the inner clamp device of FIG. The inner clamp device of this embodiment is for 900A pipe (outer diameter 914.4 mm × thickness 12.7 mm), and the total weight is 1,600 kg.

Also in FIG. 3, the existing pipe 3 on the left side and the joint pipe 7 on the right side are abutted with each other at their pipe end faces in the central portion of the drawing. A V-shaped groove is machined on the end surface of the pipe. This groove portion is welded using an automatic welding machine after fixing the pipe with an inner clamp device.

The main part of the pipe inner clamp device 1 is located inside the existing pipe 3. Clamping device 1
Are roughly divided into the left side around the main frame 11 and the right side around the spherical bearing 40 and the front flange 47. The main frame 11 uses the rear clamp 20 to fix the existing pipe 3
Fixed inside. The parts around the front flange 47 are swingably and slidably connected to the main frame 11 (center shaft 13) by a spherical bearing 40. Front flange 47
Is attracted by the end face matching cylinder 31 in the direction of the main frame 11 (in the depth direction of the existing pipe 3) until the left side face of the spacer 151 (at three circumferential positions) comes into contact with the end face of the existing pipe 3.

The structure of the main frame 11 will be described.
The main frame 11 has a central axis 13 extending in the end face direction of the existing pipe 3 at the center thereof. The central shaft 13 is a hollow member, and a spherical bearing 40 is fitted to the outer surface on the right side of the center thereof. A disk-shaped main frame flange 15 is provided at the left end of the central shaft 13 so as to expand in the radial direction. A plate-shaped structure that bends rightward extends from the flange 15. In this structure, as shown in the lower part of FIG. 3, a hydraulic motor 26 for driving the drive wheels 25 is attached to the rib 18 immediately to the right of the flange 15. A drive wheel 25 and a rear clamp cylinder 21 are attached to the rib 19 extending below the rib 18. The rear clamp cylinder 21 presses the clamp pad 23 (made of urethane) against the inner surface of the existing pipe 3 by hydraulically operating, and fixes the main frame 11 to the inner surface of the existing pipe 3. In the cylinder 21, three units are arranged in the circumferential direction. The clamping force is 2.7 tons per unit, which is 8.1 tons in total.

As shown in the upper part of FIG. 3, an end face alignment cylinder 31 is attached to the rib 17 extending rightward from the main frame flange 15. This end face matching cylinder 31 drives the rod 33 as shown in FIG. 5 to move the parts around the front flange 47 (finally to FIG.
As shown in the lower right, the spacer 151 attached to the front flange is pulled in toward the main frame 11 side.

The right end of the rod 33 of the end face matching cylinder 31 is connected to the block 37. Block 37 is 2
It is guided by the guide rod 35 of the book and moves parallel to the left and right. Flex joint 3 at the right end of block 37
9 are connected. Further flex joint 39
A guide plate 53 is connected to the right side of the. The flex joint 39 has a spherical bearing and a sliding mechanism built therein, and is capable of absorbing ± 1.75 mm and ± 5 ° misalignment (caused by the spherical bearing 40).

Guide rod 35 Tie rods 149 on both sides
Is for supporting the main clamp cylinder 111 with respect to the front flange 47. It is also for restricting the clamp pad 51 and the main clamp block 55 in the width direction. Tie rod 149 is clamp pad 5
1 and the portion passing through the main clamp block 55 is shown in FIG.
As shown in Fig. 3, the holes are elongated in the radial direction so that the two do not restrain the radial movement.

Disposed above the rear portion (left side) of the main frame flange 15 is a hydraulic valve 103 for controlling each hydraulic cylinder. Below the valve group are a coolant tank 171 and its circulation pump 173. These devices are covered with a cover 101.

FIG. 10 shows the inner clamp device 1 of FIG.
FIG. 4 is a front cross-sectional view showing the structure of the rear part (the left side of FIG. 3, the inner side of the pipe). This figure shows the drive wheel 25 and the guide roller 2.
9 shows an arrangement of 9 in the circumferential direction. Two drive wheels 25 are arranged below. The guide roller 29 has a total of 4 on both sides and the upper part.
Are arranged. Two rows of guide rollers are provided in the longitudinal direction of the pipe. The layout is designed so that the radius of the pipeline can accommodate curves up to three times the pipe diameter.

Returning to FIG. 3 again, the inner clamp device 1
Explain the right half of. The main frame 11 has a central axis 13 extending in the end face direction of the existing pipe 3 at the center thereof. A spherical bearing inner ring 41 is axially slidably fitted on the central shaft 13, and spherical bearing outer rings 43, 44 are spherically slidably fitted on the inner ring 41. The parts connected to the outer ring 43, such as the front flange 47, are swingably mounted around the center of the spherical bearing 40. The outer rings 43, 33 have a left-right half split structure.

Further, in the inner clamp device of this embodiment, as means for pressing the clamp pad 51 against the inner surface of the pipe, a means (front flange 47) for guiding the clamp pad 51 so that it can be projected and retracted in the radial direction, and the clamp pad 51. For urging the blade toward the radial center (spring 59)
And a wedge 11 having a tapered surface for pushing the clamp pad 51 in the radial direction and movable in the pipe axial direction.
7, a main clamp block 55 that has a tapered surface that slides on the tapered surface of the wedge 117 and that is connected to the clamp pad 51, and an actuator (main clamp cylinder 111) that drives the wedge 117 in the axial direction. Have.

That is, the spherical bearing outer ring 43 has the central shaft 1
3 has a front extending cylindrical portion 45 extending rightward on the outer peripheral portion. A front flange 47 is connected to the right end surface of the front extending tubular portion 45. The front flange 47, from the front extending tubular portion 45,
It extends outward, extends leftward in a cylindrical shape, and further extends outward to the flange outer edge portion 49. The drive mechanism of the main clamp pad 51 is arranged in the space on the left side of the front flange 47 and outside the spherical bearing outer ring 43.

Specifically, a sliding plate 121 (oilless metal) is attached to the outside of the spherical bearing outer ring 43 (upper part in FIG. 3). The wedge 117 moves left and right on the sliding plate 121. A main clamp block 55 is present on the wedge 117 via a sliding plate 119 (attached to the wedge 117). This main clamp block 55
Its right side surface is guided to the left side surface of the front flange 47.
Further, the left side surface thereof is guided to the guide plate 53 via the clamp pad 50. Further, the bottom surface (the surface on the center side in the radial direction) is in contact with the wedge 117 and is driven radially outward (protruding) and inward (retracting) in accordance with the lateral movement of the wedge 117.

Here, the main clamp block 55 is biased by a spring (coil spring) 59 toward the center side in the radial direction, and when the wedge 117 moves to the left, the block 137 is pulled inward. It is like this. The outer end of the spring 59 is pressed by the pressing plate 57.

The main clamp cylinder 111 that drives the wedge 117 left and right has a donut shape (hollow cylinder shape) and is located outside the central shaft 13. The clamp cylinder 111 is fixed to the front flange 47 via a flange 145 and a tie rod 149. There is a gap between the inner surface of the main clamp cylinder 111 and the outer surface of the central shaft 13. This gap absorbs relative swing of the main clamp cylinder 111 and the central shaft 13 due to the operation of the spherical bearing 40. The main clamp cylinder 111 also has a hollow cylindrical main clamp piston 113. The main clamp cylinder 111 has such a shape in order to increase the thrust of the cylinder (piston hydraulic pressure receiving surface area × hydraulic pressure) as much as possible in a narrow space.

The right end of the piston 113 is connected to the left end surface of the wedge 117 via the piston flange 115. Therefore, in accordance with the movement of the piston 113 in the left-right direction, the wedge 117 is also moved in the left-right direction (in the pipe axis direction).
Move. The lower surface of the wedge 117 is flat in the left-right direction, and the upper surface thereof is an inclined (1 / 7.6) surface. The lower surface of the wedge 117 slides on the sliding plate 121 (Oiles plate, which is fixed to the spherical bearing outer ring 43). A sliding plate 119 is attached to the upper surface of the wedge 117 and slides on the lower surface of the main clamp block 55. The role of the wedge 117 is to drive (protrude / pull in) the main clamp block 55 in the radial direction by the lateral movement of the wedge 117. The thrust of the main clamp cylinder 111 (52.6 tons) is increased by the taper effect of the wedge 117 to 400 tons. When viewed in the circumferential direction, the wedge 117 is provided so as to be divided in the circumferential direction so as to correspond to the clamp pad 51.

Next, the structure around the main clamp block 55 and the clamp pad 51 will be described with reference to FIGS. 3 and 6. On the outer diameter side of the main clamp block 55,
A main clamp pad 51 is attached. The main clamp pad 51 has an arcuate outer peripheral surface (FIG. 4). This outer peripheral surface is pressed against the inner surfaces of the ends of the existing pipe 3 and the joint pipe 7 to center and fix both pipes. When viewed in an axial cross section, the clamp pad 51 has a substantially T-shaped cross section, and the left and right corners of the outer peripheral surface are chamfered. This chamfering is for facilitating withdrawing in and out of the inner surface of the pipe. The clamp pad 51 is made of tool steel (SK material) and has abrasion resistance.

A copper backing metal 52 is fitted in the axially central portion of the outer peripheral portion of the clamp pad 51. In addition,
The clamp pad 51 has a half-split structure in which the central surface in the axial direction is split into two. A back wave groove (recess) 52-1 is formed on the outer peripheral surface of the backing metal as shown in FIG. This back wave groove 52-1 comes to the root gap portion at the time of pipe welding and plays a role of giving back wave at the time of first layer welding. The backing metal 52 is made of copper in order to easily release the heat of welding (to facilitate cooling).

Below the backing plate 52 of the clamp pad 51, there is a cooling liquid hole 51 sandwiched by two O-rings 51-2.
-1 is open. Coolant (automobile coolant, red color) passes through the holes 51-1 and functions to cool the backing metal 52 and the outer surface of the clamp pad 51 to remove the welding heat.

Next, with reference to FIGS. 7, 8 and 9, the area around the cotter pad device 130 and the spacer device 150 will be described. The cotter pad 1 of the cotter pad device 130
Reference numeral 31 is a block in which a part of the ring is cut off, as can be seen clearly in FIG. It is inserted into a gap between the clamp pads 51 divided into three in the circumferential direction (in a diagonally lower left direction in FIG. 7) and plays a role of filling the gap. Therefore, on the outer peripheral surface of the cotter pad 131, the back wave groove 131 is formed in the circumferential direction.
-1 is dug. This back wave groove 131-1 is wider than the back wave groove 52-1 of the clamp pad backing metal 52 because the inner diameter error of the pipes 3 and 7 causes the cotter pad 1 to move.
This is because the axial insertion position of 31 may be displaced, and the displacement is absorbed.

Root of cotter pad 131 (left side, FIG. 9)
The dovetail key 131-3 is connected to the. The dovetail groove key 131-3 slides in the dovetail groove 133-1 in the cotter guide 133 vertically (in the radial direction) in FIG. 7. The dovetail groove key 131-3 is urged in the radial center direction as shown in FIG. The cotter guide 133 is
It is attached to the right end surface of the cotter slider 135.
The cotter slider 135 slides left and right (axial direction) by being guided by the guide rod 137 that is inserted therethrough. At this time, the cotter lateral movement cylinder 139 drives the cotter slider 135. The cylinder 139 is installed above the guide rod 137 with its base end fixed to the spherical bearing outer ring. The rod 140 of the cylinder 139 extends to the left and is connected to the upper left end of the cotter slider 135.

The cotter pad 131 is the clamp pad 5
Inserted in the gap between 1 is centering of pipes 3 and 7.
This is after the route gap setting is completed. At that time, the spacer device 150 retracts to the right from the current position in FIGS. After that, cotter pad traverse cylinder 1
The rod 140 of 39 contracts, and the cotter slider 135,
The cotter guide 133 and the cotter pad 131 move to the right. At this time, the side slope 131-2 of the cotter pad 131
Is guided to the side slope (inclination toward the outside) 51-5 of the gap of the clamp pad 51 (outward) and proceeds to the right and at the same time to the outside in the radial direction (downward in the figure). Then, it is pressed against the inner surfaces of the ends of the pipes 3 and 7.

Next, the spacer device 150 will be described. The spacer 151 has a tip portion inserted between the end faces of the existing pipe 3 and the joint pipe 7 to set a root gap between both end faces. Spacer 151
Is attached to the tip of the spacer rod 153. The spacer rod 153 is the spacer rod guide 1
Driven by the spacer ejecting cylinder 159 through the hole of 55, it slides up and down. That is, the upper end of the rod 153 and the upper end of the rod 160 of the cylinder 159 are connected in the block 157.

The spacer rod guide 155 and the spacer ejecting cylinder 159 are fixed to the spacer slider 161. The spacer slider 161 is driven by the spacer lateral movement cylinder 163 on the guide rod 137 which is inserted through the spacer slider 161 to laterally move to the left and right (axial direction) in the drawing.
The right end of the guide rod 137 and the spacer lateral movement cylinder 163 are attached to a bracket 162 extending from the front flange 47.

As described above, the spacer 151 keeps the center position of the clamp pad 51 (pipes 3, 7) while centering the pipes 3, 7 and setting the root gap.
At the center of the end face), and at the position protruding in the outer diameter direction. Also, an end face matching cylinder (reference numeral 31 in FIGS. 3 and 5)
Thus, it is pressed against the end surface (root portion) of the existing pipe 3 via the front flange 47 and the like. However, after centering the pipe, setting the root gap, and fixing the pipe, the pipe is pulled in the inner diameter direction and retracted in the right direction of the drawing so that the cotter pad 131 can advance.

Returning to FIG. 3, at the right end of the central shaft 13,
The front clamp 60 is attached via a rib 64 extending in the outer diameter direction. The front clamp 60 has a front clamp cylinder 61. The front clamp cylinder 61 drives (projects) a front clamp pad 63 (made of urethane) in the radial direction to connect the pad to the inner surface of the pipe 7. Press against. As a result, the central shaft 13 (main frame 11)
Is fixed to the joint pipe 7.

The front cover 65, which is placed against the right end surface of the central shaft 13, is provided with a handle 67 for manually operating the main frame 11 (although it is extremely heavy). Also, a cable (hydraulic pressure, electricity) 69 is attached. This cable is connected to a control wagon for controlling the clamping device. Further, a cooling liquid tube 66 including a transparent portion is attached on the front cover 65,
The presence or absence of the cooling liquid can be confirmed by looking at this. The operation of the pipe inner clamp device shown in FIGS. 3 to 10 is as described above.

[0054]

As is apparent from the above description, the inner clamp device of the present invention has a clamp pad (including a cotter pad) which is also used as a back metal and is pressed against the inner surface of the pipe.
Exists over the entire circumference and there is no defect in the backing of the welded portion, so that welding defects due to poor backing can be prevented. Further, the main welding can be continuously performed with the clamped, and the work efficiency is improved.

Further, when a route gap setting spacer is mechanized and incorporated into the inner clamp device, and a means for bringing the spacer into contact with the end surface of one pipe (generally, the existing pipe) is also provided. Can significantly reduce the time and effort required to set the gap.

[Brief description of drawings]

FIG. 1 is a schematic view conceptually showing a pipe inner clamp device and its operation according to an embodiment of the present invention.

FIG. 2 is a schematic view conceptually showing a pipe inner clamp device and its operation according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing an example of the internal structure of the inner clamp device conceptually shown in FIGS. 1 and 2.

4 is a partial cross-sectional front view showing a clamp pad portion of the inner clamp device of FIG.

5 is a plan view showing details around the end face matching cylinder of the inner clamp device of FIG. 3. FIG.

6 is a cross-sectional view showing details of a clamp pad portion in the inner clamp device of FIG.

7 is a side sectional view showing details around a cotter pad device and a spacer device in the inner clamp device of FIG.

8 is a front view showing details around a cotter pad device and a spacer device in the inner clamp device of FIG.

9 is a bottom view of details around the cotter pad device and the spacer device in the inner clamp device of FIG. 3 as viewed from the outer peripheral surface.

10 is a front sectional view showing the structure of the rear portion (the left side of FIG. 3, the inner side of the pipe) of the inner clamp device of FIG.

[Explanation of symbols]

1 Inner Clamp Device Main Body 2 Weld Bead 3 Existing Pipe 3-1 Bevel 3-2 Root 5 Welder Head 5-1 Welding Torch 6 Guide Rail 7 Joint Pipe 7-1 Bevel 7-2 Root 11 Main Frame 13 Central shaft 15 Main frame flange 17, 18, 19 Rib 20 Rear clamp 21 Rear clamp cylinder 23 Rear clamp pad 25 Drive wheel 26 Hydraulic motor 27 Belt 28 Driven wheel 29 Guide roller 31 End face matching cylinder 33 End face aligning cylinder rod 35 Guide rod 37 Block 39 Flex joint 40 Spherical bearing 41 Spherical bearing inner ring 43, 44 Spherical bearing outer ring 45 Front extension cylinder part 47 Front flange 49 Flange outer edge part 50 Main clamp 51 Main clamp pad 51-1 Coolant 51-2 O-ring 51-3 , 51- 4 Chamfer 51-5 Side slope 52 Backing metal 52-1 Back wave groove 53 Guide plate 55 Main clamp block 57 Holding plate 59 Spring 60 Front clamp 61 Front clamp cylinder 63 Front clamp pad 64 Rib 65 Front cover 66 Coolant tube 67 Handle 68 Chain 69 Cable 101 Rear cover 103 Hydraulic valve 111 Main clamp cylinder 113 Main clamp piston 115 Piston flange 117 Wedges 119, 121 Sliding plate 130 Cotta device 131 Cotta pad 131-1 Back wave groove 131-2 Side slope 133 cotter guide 134 spring 135 cotter slider 136 end plate 137 guide rod 139 cotter traverse cylinder 140 cotter traverse cylinder rod 141 tie plate 149 tyro 150 Spacer device 151 Spacer 153 Spacer rod 155 Spacer rod guide 157 Block 159 Spacer protruding cylinder 161 Spacer slider 162 Bracket 163 Spacer traverse cylinder 171 Coolant tank 173 Coolant circulation pump

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ikuo Mibu 2982-3 Sugaya, Naka-machi, Naka-gun, Ibaraki Prefecture (72) Inventor Koji Ito 14-19 Taisei-cho, Hitachinaka City, Ibaraki Prefecture

Claims (6)

[Claims] 1. A pipe inner clamp device for fixing two pipes that are butted at their ends from the inside of the pipes; a circle that can be pressed against the inner surfaces of the butted ends of the two pipes. A clamp pad also serving as a backing metal, which is divided into several parts in the circumferential direction, and a cotter pad which is inserted into a gap between the divided clamp pads and serves as a part of the backing metal to the inner surface of the pipe end. A pipe inner clamp device comprising: 2. The pipe inner clamp device according to claim 1, wherein the clamp pad and / or the cotter pad has a passage for the liquid refrigerant therein. 3. The pipe inner clamp device according to claim 1, wherein a copper backing metal is fitted on the outer peripheral surface of the clamp pad and / or the cotter pad. 4. A plurality of spacers provided in a circumferentially dispersed manner, which are protruded between both end faces of the two pipes and can be drawn from the end faces toward the inner diameter side, and the plurality of spacers. 4. A means for retracting the spacer in the depth direction of the one pipe so that each of the spacers comes into contact with the end surface of one of the two pipes. The described pipe inner clamp device. 5. The cotter pad is configured to be capable of reciprocating between a position inserted into a gap between the divided clamp pads and a position removed from the gap. In addition, the spacer is also configured so as to be able to reciprocate between both positions of the position inserted into the gap between the divided clamp pads and the position removed from the gap. The cotter pad is located at the insertion position from the final stage of pipe clamping (after centering and after setting the root gap) to the first layer welding of the pipe butt portion, and forms a part of the entire circumference backing metal. The pipe inner clamp device according to any one of claims 1 to 4, wherein the pipe inner clamp device is located at the insertion position when the root gap is set. 6. The pipe inner clamp device according to claim 5, wherein the cotter pad and the spacer are provided on a pair of guide rods so as to be reciprocally opposed to each other.