JP2004019854A - Constant water feeding interposition method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a constant water feeding interposition method capable of using endless connection pipe elements in the circumferential direction of a pipe. <P>SOLUTION: This constant water feeding interposition method comprises a correction step for correcting the flat existing pipe 1 to a complete circular pipe, a generating step for generating cut pieces by cutting the corrected existing pipe at two positions apart from each other in the axial direction Y, a removal step for removing the cut pieces from a pipeline, an insert step for inserting a pair of right and left connection pipe elements 4 formed endlessly in the circumferential direction of the pipe from the radial outside of the existing pipe 1, and a moving step for moving the pair of connection pipe elements 4 slidably in the axial direction Y of the existing pipe 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a continuous water insertion method.
[0002]
[Prior art]
Conventionally, in a valve insertion method, a split connecting wheel is attached to an existing pipe in advance, and a main pipe element such as a valve or a stopper (plug) is inserted into a removed portion obtained by cutting and removing the existing pipe. Thereafter, the split wheel is slid, and the existing pipe and the main piping element are sealed with the split wheel (for example, see Japanese Patent Application Laid-Open No. 4-1944491).
[0003]
[Problems to be solved by the invention]
However, the split connecting wheel is divided in the pipe circumferential direction, and after being mounted on the outer circumference of the existing pipe, the split split halves are integrated by welding or bolting. Therefore, the following problem occurs.
That is, in the case of joining by bolting, the rubber packing deteriorates, so that the sealing property is reduced and water may leak. Further, since the split connecting wheel is divided, the manufacturing cost is higher than that of the endless connecting wheel.
On the other hand, in the case of joining by welding, since the welding is performed on site, the construction period becomes long, and since the inside of the welded portion cannot be sufficiently rust-proofed, corrosion may occur from the inside of the welded portion.
[0004]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide an uninterrupted water insertion method capable of using an endless joining piping element in a pipe circumferential direction.
[0005]
[Means for Solving the Invention]
In order to achieve the above object, the present invention provides a method for inserting continuous water into a pipe, comprising: a straightening step for straightening an existing pipe so as to approach a perfect circle; and a step of separating the straightened existing pipe in a pipe axis direction. A generation step of cutting at a location to generate a piece, a removing step of removing the piece from the pipeline, and a pair of left and right joining piping elements that are endless in the pipe circumferential direction are already installed at the removed portion where the piece has been removed. The method includes an insertion step of inserting the pair of joining piping elements from the outside in the radial direction of the pipe, and a moving step of sliding the pair of joining piping elements in the pipe axis direction of the existing pipe. Here, the generation step, the removal step, the insertion step, and the movement step are performed while the existing pipe is being corrected by the pipe correction tool.
[0006]
In the present invention, the “existing pipe” refers to a pipe in which a fluid such as water flows inside the pipe, and is generally buried underground.
[0007]
On the other hand, in the continuous water insertion method according to the second invention, the main piping element and the existing pipe are joined by the joining piping element in the following order.
(1) The closed case is rotatably attached to the existing pipe so that the closed case divided into a plurality of pieces in the circumferential direction of the existing pipe surrounds a part of the existing pipe in an airtight state. A cutting tool which is supported for rotation about the cutter axis and has a plurality of cutting blades is accommodated in the closed case.
(2) While rotating the cutting tool around the cutter axis,
(I) sending the cutting tool radially inward of the existing pipe to cut the existing pipe;
(Ii) In order for the cutting tool to cut the existing pipe over the entire circumference in the circumferential direction, the entire closed case is rotated together with the cutting tool in the circumferential direction of the existing pipe.
(3) The steps (1) and (2) are performed at two locations separated in the tube axis direction to generate a slice.
(4) After surrounding the section and the closed case with a tank, removing the section from the tank to generate a removed portion.
(5) Inserting the main piping element into the removed portion in a state where the endless joining piping element in the pipe circumferential direction is mounted on the outer periphery of the main piping element.
(6) After this insertion, the joining pipe element is slid to the existing pipe side so that the joining pipe element straddles the main pipe element and the end of the existing pipe.
[0008]
The “main piping element” refers to, for example, a piping element that can be used by being joined to an existing pipe such as a seismic joint in addition to a stopper (plug) or valve.
The term "sealed" does not mean completely closed, but means that construction can be performed without interruption. Therefore, the “sealed case” refers to a case having a pressure resistance capable of withstanding the pressure of the fluid flowing in the existing pipe and a certain degree of water stopping performance.
Further, "to bend in an airtight state" means to seal so as not to hinder operations such as cutting and insertion of a valve after cutting. Therefore, for example, a drain hole may be provided in the closed case, the drain hole may be opened during cutting, and chips may be discharged from the drain hole together with water.
[0009]
Since the "cutting tool" used in this cutting method has a plurality of cutting blades, the cutting tool does not include a cutting tool or a cutter wheel having a single continuous cutting blade. . As the “cutting tool” used in the present cutting method, besides a diamond wheel or a metal saw, a column-shaped cutting tool having a plurality of cutting blades on the tip end surface and the outer peripheral surface of the column can be used. .
The columnar shape means that in addition to a cylinder, a truncated cone, a shape obtained by adding a cone to a cylinder, and a conical shape are also included. Further, the cutting tool may have a columnar shape whose length is shorter than the outer diameter of the cutting tool.
When cutting an existing pipe having a mortar lining on the inner surface of the pipe, it is preferable to use a cutting tool provided with a large number of cutting blades (tips) made of cemented carbide. Further, it is more preferable to use a cutting tool having a center drill.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will be more clearly understood from the following description of preferred embodiments thereof with reference to the accompanying drawings. However, the examples and figures are for illustration and description only and should not be used to define the scope of the invention. The scope of the present invention is defined by the appended claims. In the accompanying drawings, the same part numbers in a plurality of drawings indicate the same or corresponding parts.
[0011]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a sealed case 7, which will be described later, is attached to the existing pipe 1 in which a fluid such as water flows in the pipe at two locations separated in the pipe axis direction Y. Pipe straightening tools 8 are attached to the left and right sides of the sealed case 7, respectively.
[0012]
Pipe straightening tool 8:
As shown in FIG. 2, the pipe straightening tool 8 is for straightening an existing flat pipe 1 into a perfect circle as described later. The pipe straightening tool 8 includes a ring 80 having an inner diameter larger than the outer diameter of the existing pipe 1. The ring 80 is divided in the circumferential direction R.
The ring 80 is provided with a female screw 83 (FIGS. 2B and 2C). The female screw 83 is provided at a plurality of locations (usually eight or more locations) apart from each other in the circumferential direction R of the ring 80. First and second pushers 91 and 92 are alternately screwed into the plurality of female screws 83.
[0013]
2B and 2C are enlarged cross-sectional views taken along line IIb-IIb and line IIc-IIc in FIG. 2A, respectively.
As shown by the two-dot chain lines in FIGS. 2B and 2C, the pushers 91 and 92 are screwed into the female screw 83 and rotated. By this rotation, the tips 95 and 96 of the pushers 91 and 92 come into contact with the outer peripheral surface of the existing pipe 1 and can press the outer peripheral surface. As described later, by pushing the pushers 91 and 92 from the outside of the existing pipe 1 toward the center of the existing pipe 1, the cross-sectional shape of the existing pipe 1 is corrected so as to approach a perfect circle. .
[0014]
A collar 94 is formed at a rear end portion of the pushers 91 and 92. On the other hand, a stopper 84 is fixed to the outer periphery of the ring 80. The stopper 84 is made of, for example, rubber. When the pushers 91 and 92 are advanced toward the center of the existing pipe 1, the collar 94 comes into contact with the stopper 84, and the rotational torque of the pushers 91 and 92 increases. Therefore, the stopper 84 and the brim 94 constitute a restraining means for restraining the pushers 91 and 92 from moving further inward.
Here, the flattened existing pipe 1 is corrected by the tips 95 and 96 of the pushers 91 and 92 pushing the outer circumference of the existing pipe 1 and stopping at a predetermined position where the flattening is corrected. The stop position is set near the position where the tips of the pushers 91 and 92 abut the outer circumference of the existing pipe 1 when the cross-sectional shape of the existing pipe 1 is a perfect circle. Therefore, the positional relationship between the stopper 84 and the flange 94 is set such that the tips of the pushers 91 and 92 are at the stop position.
[0015]
As shown in FIG. 2B, the distal end 95 of the first pusher 91 is depressed, and abuts against the outer peripheral surface of the existing pipe 1 to push the outer peripheral surface. The distal end 95 fits into the outer peripheral surface of the existing pipe 1 and fixes the pipe straightening tool 8 to the existing pipe 1.
On the other hand, as shown in FIG. 2C, a rolling element such as a ball 97 that pushes the outer circumference of the existing pipe 1 is provided at the distal end 96 of the second pressing tool 92. The ball 97 is rotatably provided at the tip 96. As will be described later, the rotation of the ball 97 allows the pipe straightening tool 8 to move in the pipe axis direction Y (FIG. 1) while pressing the outer peripheral surface of the existing pipe 1.
[0016]
Sealed case 7:
FIG. 3 is a longitudinal sectional view taken along line II of FIG.
As shown in FIG. 3, the closed case 7 includes first and second split cases 71 and 72 that are half-split. The closed case 7 is attached to the existing pipe 1. A rubber ring 73 seals between the cases 71 and 72 and between the two split cases 71 and 72 and the existing pipe 1. The sealed case 7 is attached to the existing pipe 1 so as to surround the existing pipe 1 in an airtight state and to be rotatable in the circumferential direction R of the existing pipe 1.
[0017]
A cutting tool 77 is accommodated in the closed case 7 shown in FIG. The cutting tool 77 is rotatable around the cutter axis 75 and has a plurality of cutting blades.
As shown in FIGS. 4A and 4B, while rotating the cutting tool 77 around the cutter shaft 75, the cutting tool 77 is fed inward in the radial direction X of the existing pipe 1, and the existing pipe 1 is cut. Thereafter, the existing pipe 1 is cut by rotating the cutting tool 77 together with the sealed case 7 in the circumferential direction R of the existing pipe 1 (FIG. 3). The section 1C (FIG. 5) is generated by the cutting. The cutting blade of the cutting tool 77 is formed in a step shape. Therefore, as shown in FIG. 4C, the existing pipe 1 and the section 1 </ b> C cut by the cutting tool 77 have a taper 13 in the cut groove 12.
[0018]
Work tank 2:
FIG. 5 shows a state where a part of the existing pipe 1, the section 1 </ b> C, and the closed case 7 are hermetically surrounded by the work tank 2 after the generation of the section 1 </ b> C.
As shown in FIG. 5, the work tank 2 is composed of work lower tanks 21 and 22, a work gate valve 23, and a work upper tank 24 divided in a vertical direction (circumferential direction). A lifting band 11 connected to an elevating shaft 25 is wound around the existing pipe 1. The pipe straightening tools 8, 8 located between the two sealed cases 7, 7 are moved so as to come into contact with the lifting band 11, as described later.
[0019]
The work lower tanks 21 and 22 are provided with a push-pull bar 5 for sliding the closed case 7 and the connecting wheel 4 (joining piping element) of FIG. 10 in the pipe axis direction Y.
As shown in FIG. 6, the push-pull bar 5 has a hollow outer 55. A stroke screw 50 is formed on the outer periphery of the outer 55. The stroke screw 50 is screwed in the pipe axis direction Y with a female screw 22a provided in the work lower tank 22 (21).
[0020]
As shown in FIG. 7, inside the push-pull bar 5, an engagement bar 51 is provided slidably in the axial direction Y and rotatable in the circumferential direction. On the other hand, a flange 76 is integrally formed at the end of the closed case 7 on the push-pull bar 5 side in FIG. A first engaged portion 74 having a female thread is fixed to the flange 76. At the end of the engaging rod 51 in FIG. 7, an engaging male screw 52 screwed to the first engaged portion 74 is provided. A conical guide portion 53 for guiding the engaging male screw 52 into the female screw of the first engaged portion 74 is provided at the tip of the engaging male screw 52.
When the outer thread 55 of the push-pull bar 5 is rotated with respect to the lower work tank 22 after the engaging male screw 52 is engaged with the first engaged portion 74, the closed cases 7 are moved in a direction approaching each other. Moving.
[0021]
As shown in FIG. 9, after the closed case 7 is moved, the section 1C is pulled up and stored in the work upper tank 24, and the work gate valve 23 is closed. Can be removed.
[0022]
Butterfly valve 3:
FIG. 10 shows a state in which, after the removal, the work upper tank 24 in which the butterfly valve 3 and the connecting wheel 4 are stored is attached to the work lower tank 22.
As shown in FIG. 10, the butterfly valve 3 to be inserted into the removed portion E of the existing pipe 1 is housed in the work upper tank 24 so as to be suspended from the elevating shaft 25. Short pipes 31, 31 are previously joined to both sides of the butterfly valve 3. The short pipes 31 have substantially the same outer diameter as the existing pipe 1. One end of the short pipe 31 is connected to the butterfly valve 3 via flanges 32, 32. The other end of the short tube 31 is formed with a taper 33. The short pipe 31 forms a main piping element together with the butterfly valve 3.
[0023]
Connecting wheel 4:
Connection rings (joining piping elements) 4 and 4 are respectively mounted on the outer circumference of the short pipe 31 so as to be movable in the pipe axis direction Y. The connecting ring 4 is formed endlessly (integrally) in the pipe circumferential direction, and has packing insertion portions 40 for inserting rubber packings at both ends as shown in FIG. A second engaged portion 42 is provided at an outer end of the connecting wheel 4 in the tube axis direction Y via a bracket 41. The engaged portion 42 is for connecting the push-pull bar 5 (FIG. 5) and the connecting ring 4, and has an internal thread formed therein. Further, the connecting wheel 4 is provided with a pair of grooves 44 for accommodating the O-ring 100 for temporary water stoppage.
Each of the connecting wheel 4 and the short pipe 31 has a circumferential surface 4f and an outer peripheral surface 31f having a perfect circular cross section.
[0024]
Continuous insertion method:
Next, the insertion step of the present invention will be described by exemplifying a case in which two existing pipes that are flattened vertically are cut.
Straightening process;
First, in a state where the fluid (water) is flowing in the existing pipe 1 of FIG. 12A, a pair of sealed cases 7 are attached to the existing pipe 1 at predetermined intervals, and a part of the existing pipe 1 is airtightly sealed. Surround in the state. Next, a pair of pipe straightening tools 8, 8 are attached to each of the sealed cases 7 in FIG.
[0025]
As shown by the two-dot chain lines in FIGS. 2 (b) and 2 (c), after the mounting, first, the pushers 91, 92 are moved toward the center of the existing pipe 1 with respect to the upper and lower parts 11, 11 of the pipe and the vicinity thereof. When the advance is made in the X direction, the collar 94 and the stopper 84 come into contact with each other, and the rotational torque of the pushers 91 and 92 increases. By advancing the pushers 91 and 92 to the contact position, the pipe straightening tool 8 is centered with respect to the existing pipe 1.
Next, when the horizontal portions 10 and 10 of the pipe 1 and the portions in the vicinity thereof are advanced toward the centers of the pushers 91 and 92, if the existing pipe 1 is flat, the collar 94 contacts the stopper 84 before it contacts the stopper 84. The tips 95 and 96 of the pushers 91 and 92 abut on the outer peripheral surface of the existing pipe 1. Thereafter, the abutting pushers 91 and 92 are further screwed in, and the flattened existing pipe 1 is pushed by the tips 95 and 96 to correct the pipe so that it approaches a perfect circle.
Each of the pair of pipe straightening tools 8 attached to both sides of the closed case 7 is pressed by the pushers 91 and 92 to perform straightening.
[0026]
Generation step;
After the straightening, the cutting tool 77 shown in FIG. 1 is rotated around the cutter axis 75 and sent inward in the radial direction X of the existing pipe 1, and as shown in FIG. To cut. Thereafter, while the existing pipe 1 is being corrected by the pipe straightening tool 8, the whole of the sealed case 7 is rotated together with the cutting tool 77 in the circumferential direction R of the existing pipe 1 (FIG. 3) to cut the existing pipe 1. I do. As shown in FIG. 12B, by performing the cutting at two places separated in the pipe axis direction Y, the existing pipe 1 is cut at two places to generate a section 1C.
[0027]
Removal step;
After the generation of the section 1C, the lifting band 11 (FIG. 5) is wound around the section 1C and fixed. Then, after removing the cutter shaft 75 and the cutting tool 77 from the sealed case 7, the pipe straightening tools 8, 8 positioned between the two sealed cases 7, 7 are moved closer to each other. Abut.
Here, in order to move the pipe straightening tool 8, of the first and second push tools 91 and 92 that are in contact with the existing pipe 1 shown in FIG. Loosen only the first pusher 91 to release the contact between the first pusher 91 and the existing pipe 1. After the release, the pipe straightening tool 8 is pushed and moved in the pipe axis direction Y. Since the ball 97 is provided at the tip of the second pusher 92, the ball 97 moves while pressing the outer peripheral surface of the existing pipe 1 so that the straightening of the pipe can be performed without changing the degree of correction of the existing pipe 1. The tool 8 can be moved smoothly.
[0028]
After the movement, the lower work tanks 21 and 22 are attached as shown in FIG. After this mounting, the push-pull bar 5 is connected to the flange 76 of the sealed case 7 as shown in FIG. That is, when the outer 55 of the push-pull bar 5 shown in FIG. 6 is rotated to approach the connecting wheel 4, the guide portion 53 is inserted into the female screw of the first engaged portion 74. When the engaging rod 51 is rotated while being pushed after the insertion, the guide portion 53 is guided along the inner periphery of the first engaged portion 74, and the engaging male screw 52 of FIG. The push-pull bar 5 is screwed into the female screw of the portion 74, and is connected to the flange 76 of the sealed case 7.
After this connection, the work partition valve 23 and the work upper tank 24 indicated by the two-dot chain line in FIG. 5 are stacked on the work lower tank 22 to assemble the work tank 2.
[0029]
Thereafter, the work gate valve 23 is opened, the push-pull bar 5 is advanced, and the two sealed cases 7 shown in FIG. 12 (c) are brought close to each other so as to be in contact with the inner pipe straightening tool 8. Move.
That is, after the connection, the push / pull bar 5 is advanced by rotating the outer 55 of the push / pull bar 5, and the sealed case 7 is moved. Due to this movement, the whole of the sealed case 7 shown in FIG. 8 moves onto the section 1C, and the end of the sealed case 7 comes into contact with the moved pipe straightening tool 8 and stops.
[0030]
Here, as shown in FIG. 4C, the existing pipe 1 cut by the cutting tool 77 has a taper 13 formed in a cutting groove 12 thereof. On the other hand, the rubber ring 73 of the sealed case 7 is bonded to the sealed case 7 with a rubber-based adhesive so that the rubber ring 73 does not fall into the existing pipe 1 from a cut portion of the existing pipe 1 during movement.
[0031]
After the movement of the sealed case 7, the connection between the sealed case 7 and the push-pull bar 5 is released, and the push-pull bar 5 is retracted outside the cut portion.
That is, the connection between the engagement screw 52 and the first engaged portion 74 is released by rotating the engagement rod 51 shown in FIG. After the release, the push-pull bar 5 is retracted by rotating the outer 55 in reverse with respect to the work lower tank 22.
[0032]
Thereafter, as shown in FIG. 9, the work partition valve 23 is opened, the section 1 </ b> C is pulled up, and stored in the work upper tank 24. After the storage, the work gate valve 23 is closed. After this valve opening, the upper work tank 24 containing the section 1C is removed.
[0033]
Insertion process;
Thereafter, as shown in FIG. 10, the work upper tank 24 in which the connecting wheel 4 and the butterfly valve 3 are stored is attached to the work gate valve 23. After the installation, as shown in FIG. 13, the work gate valve 23 is opened and the butterfly valve 3 is lowered. Here, the butterfly valve 3 is lowered so that the short pipe 31 and the existing pipe 1 are aligned with each other so that the connecting wheel 4 can slide to the existing pipe 1 and inserted into the removed portion E.
[0034]
Moving process;
After the lowering, when the outer 55 of the push-pull bar 5 shown in FIG. 14 is rotated to approach the connecting wheel 4, the guide portion 53 is inserted into the female screw of the second engaged portion 42. Thereafter, the engaging rod 51 (FIG. 7) is rotated while being pushed in, so that the engaging male screw 52 is screwed into the female screw of the second engaged portion 42, and the push / pull bar 5 is moved to the second engaged portion 42. And is connected to the connecting wheel 4 via.
[0035]
After the connection, the outer wheel 55 of the push-pull bar 5 is rotated backward to retract, so that the connecting wheel 4 straddles both ends of the existing pipe 1 and the short pipe 31 as shown in FIG. The connecting wheel 4 is slid toward the existing pipe 1 by a predetermined stroke. By this movement, as shown in FIG. 16, temporary water is stopped between the connecting wheel 4 and the existing pipe 1 and the short pipe 31 by the O-rings 100 and 100 mounted on the connecting wheel 4 in advance.
[0036]
After the temporary stoppage, the water in the work tank 2 in FIG. 15 is drained, the work tank 2 is disassembled, and the bracket 41 (FIG. 14) is removed. Thereafter, as shown in FIG. 16, split push rings 6 are attached to both ends of the connecting ring 4, and the rubber ring 60 for final water stop is pushed into the packing insertion portion 40 of the connecting ring 4, and a speed reducer is attached to the butterfly valve 3. Attach.
[0037]
As described above, in the present continuous water insertion method, the endless connecting ring 4 can be used in the pipe circumferential direction R for joining the existing pipe 1 and the butterfly valve 3.
[0038]
As shown in FIG. 17, if a rubber ring 60 is attached to the outer periphery of the connecting wheel 4 in advance and a pressing ring 6 is attached to the end, the endless rubber ring 60 and the pressing ring 60 can be used in the pipe circumferential direction. .
[0039]
18 to 21 show modified examples.
FIG. 18A shows that after the existing pipe 1 is cut, a lifting band 11 for lifting the section 1C is fixed to the section 1C, and once the section 1C is taken out, a connecting ring (about the outer circumference of the section 1C) is attached. The figure shows a state in which the joint pipe element (4A) is mounted and suspended and stored in the upper work tank 24.
[0040]
The connecting wheel 4A is formed endlessly in the pipe circumferential direction. As shown in FIG. 20 showing a connection state between the push-pull bar 5 and the connecting ring 4, the connecting ring 4A has an engaging portion 42 provided on the outer end portion via a bracket 41, and a packing inserting portion 40. have. On the other hand, a plate-like flange 45 for compressing a seat packing 36 described later is provided at the other end of the connecting wheel 4A. Note that a pipe straightening tool 8 is attached to the existing pipe 1, and the existing pipe 1 is corrected so that its cross section approaches a perfect circle.
[0041]
First, as shown in FIG. 18 (b), the working gate valve 23 is opened, the section 1 C is lowered, and the section 1 C is inserted into the removed portion E. At the time of such insertion, positioning of the section 1C and the existing pipe 1 is performed so that the connecting wheel 4A can slide to the existing pipe 1. Next, as shown in FIG. 18 (c), the push-pull bar 5 and the connecting wheel 4A are connected, and the connecting wheel 4A is slid toward the existing pipe 1 and moved onto the existing pipe 1.
[0042]
After the movement, the section 1C is pulled up again and stored in the upper work tank 24. After the storage, the work gate valve 23 is closed, and the section 1C is removed together with the work upper tank 24 as shown in FIG. Thereafter, as shown in FIG. 19B, after the butterfly valve (main piping element) 3a is stored in the work upper tank 24, the work upper tank 24 is attached to the work partition valve 23. The butterfly valve 3a has annular plate-like plate-like flanges 35 at both ends, and for example, an annular plate-like seat packing 36 is adhered to each flange 35 as shown in FIG. It is.
[0043]
Thereafter, as shown in FIG. 19C, the work gate valve 23 is opened, the butterfly valve 3A is lowered, and the butterfly valve 3A is inserted into the removed portion E. After the insertion, the connecting wheel 4A is slid toward the butterfly valve 3A. By this movement, the plate-like flange 45 in FIG. The seat packing 36 is compressed between the plate-like flange 45 and the flange 35 of the butterfly valve 3A by the axial force of the push-pull bar 5, and temporary water is stopped between the connecting ring 4A and the existing pipe 1 and the butterfly valve 3A.
[0044]
After the temporary stoppage, the water in the work tank 2 is drained and disassembled, and the bracket 41 is removed. Thereafter, the plate-like flange 45 and the flange 35 are connected, and at the same time, a pressing ring is attached to the existing pipe 1 and the rubber ring for final water stop is pressed into the packing insertion portion 40 of the connecting ring 4A.
[0045]
As described above, even with the butterfly valve 3A having the flanges 35 at both ends, the connection between the existing pipe 1 and the butterfly valve 3A is endless in the pipe circumferential direction R by attaching the connecting ring 4A to the outer periphery of the section 1C. Connecting rings can be used.
[0046]
As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will easily envisage various changes and modifications within the obvious scope upon reading this specification.
For example, the first invention does not limit the cutting method of the existing pipe, and the cutting tool may be cut by rotating the cutting tool around the existing pipe.
In the above-described embodiment, the ball 97 is provided at the tip of the second pressing tool 92. However, instead of the ball 97, a roller that rotates in the tube axis direction Y may be provided. May be provided. Further, as shown in FIG. 21, a plurality of pushers 91 and 92 may be provided outside the rubber ring 73 of the sealed case 7.
Further, in the above embodiment, the pipe straightening tools 8 are attached to both sides of the closed case 7, but the pipe straightening tools 8 may be provided on only one side of each closed case 7.
[0047]
The method of cutting the existing pipe 1 is not particularly limited as long as it is a cutting method capable of providing a removal portion E into which a main piping element such as the butterfly valves 3 and 3A can be inserted.
In addition, although the axial force of the push-pull bar 5 is used to slide the connecting wheels 4 and 4A and the sealed case 7, fluid pressure using air or water pressure may be used. Furthermore, although the push-pull bar 5 is provided in the lower work tanks 21 and 22 as a device for sliding the connecting wheels 4 and 4A, the device may be any device that can slide the connecting wheels 4 and 4A. . Therefore, for example, it may be provided in the butterfly valves 3 and 3A and the section 1C.
When the water pressure in the existing pipe 1 is low, it is not necessary to use the highly airtight work tank 2. Further, in the case of an outlet of a drainage pond without water pressure, the butterfly valves 3 and 3A and the section 1C are directly connected to the opening of the lower work tank 22 without using the work separation valve 23 and the upper work tank 24. You may insert in the removal part E.
Accordingly, such changes and modifications are to be construed as being within the scope of the invention as defined by the appended claims.
[0048]
【The invention's effect】
As described above, according to the first and second inventions, in the continuous water insertion method, an endless connecting pipe element can be used for connecting an existing pipe and a main pipe element. Therefore, unlike the case where the split halves of the divided joining piping elements are bolted together, there is no possibility that the rubber packing is deteriorated, so that the sealing performance is improved. On the other hand, unlike the case where the divided joining pipe elements are welded to each other, there is no possibility of corrosion occurring from the inside of the welded portion.
Further, since the joining pipe element is not divided in the pipe circumferential direction, it can be manufactured at low cost. Furthermore, since it is not necessary to weld the joint piping elements divided at the site, the construction period can be shortened.
In particular, in the first invention, the existing pipe is corrected so as to be close to a perfect circle, so that the main piping element and the connecting piping element may be produced based on the perfect circle. Therefore, since it is not necessary to process these piping elements into a flat shape, the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a closed case and a pipe straightening tool showing a straightening step in an embodiment of a method for inserting water without interruption according to the present invention.
2 (a) is a front view of a tube straightening device, FIG. 2 (b) is a cross-sectional view taken along line IIb-IIb of FIG. 2 (a), and FIG. 2 (c) is IIc- of FIG. 2 (a). It is IIc line sectional drawing.
FIG. 3 is a vertical sectional view taken along the line II of the sealed case of FIG. 1;
4 (a) and 4 (b) are cross-sectional views of a sealed case and a pipe straightening tool, and FIG. 4 (c) is a partial cross-sectional view of the sealed case.
FIG. 5 is a longitudinal sectional view showing a state where the work tank is assembled.
FIG. 6 is a sectional view showing a push rod.
FIG. 7 is a cross-sectional view showing a structure of a push rod.
FIG. 8 is a cross-sectional view of a sealed case and the like showing an engagement state between a push rod and a connecting wheel.
FIG. 9 is a longitudinal sectional view showing a removing step.
FIG. 10 is a longitudinal sectional view showing an insertion step.
FIG. 11 is a longitudinal sectional view showing a state where a connecting ring is attached to a short pipe.
[FIG. 12] FIG. 12 is a process diagram showing a continuous water insertion method.
FIG. 13 is a vertical sectional view showing an insertion step.
FIG. 14 is a longitudinal sectional view showing a pipe state before a connecting wheel is moved.
FIG. 15 is a longitudinal sectional view showing a pipe state after the connecting wheel is moved.
FIG. 16 is a sectional view showing a piping structure.
FIG. 17 is a sectional view showing a connecting wheel according to a modification.
FIG. 18 is a process chart showing a method of inserting water without interruption according to another modification.
FIG. 19 is a process chart showing the continuous water insertion method.
FIG. 20 is a sectional view showing the structure of the connecting wheel.
FIG. 21 is a sectional view of a main part showing another modification.
[Explanation of symbols]
1: Existing pipe
2: Work tank
3, 3A: Butterfly valve (main piping element)
4, 4A: Connecting wheel (Piping element for joining)
7: Sealed case
75: Cutter axis
77: Cutting tool
E: Removal part
R: Pipe circumferential direction
X: Radial direction
Y: Pipe axis direction

Claims (4)

After cutting a part of the existing pipe to generate a section, the section is removed, a main pipe element is inserted into the removed portion from which the section has been removed, and the main pipe element and the existing pipe are joined. In the uninterrupted water insertion method of joining with piping elements for
A straightening step of straightening the existing pipe with a pipe straightening tool so that a force pushing from the outside of the existing pipe toward the center of the existing pipe is applied to the existing pipe so that the cross-sectional shape of the existing pipe approaches a perfect circle. When,
A generation step of cutting the existing pipe at two locations separated in the pipe axis direction to generate a section;
Removing the section from the conduit;
An insertion step of inserting a pair of left and right joining piping elements that are endless in the circumferential direction of the pipe from the radially outer side of the existing pipe to the removed portion where the section has been removed,
A moving step of sliding the pair of connecting piping elements in the pipe axis direction of the existing pipe,
Here, an uncut water insertion method in which the generating step, the removing step, the inserting step, and the moving step are performed while the existing pipe is being corrected by the pipe straightening tool. In claim 1,
In the inserting step, in a state where the pair of joining piping elements are mounted on the outer periphery of the main piping element, the pair of joining piping elements are inserted into the removed portion together with the main piping element,
In the moving step, the connecting pipe elements are moved from the main pipe element toward the existing pipe, and the pair of connecting pipe elements respectively span the main pipe element and ends of the existing pipe. A continuous water insertion method characterized by: After cutting a part of the existing pipe to generate a section, the section is removed, a main pipe element is inserted into the removed portion from which the section has been removed, and the main pipe element and the existing pipe are joined. In the uninterrupted water insertion method of joining with piping elements for
(1) The closed case is rotatably attached to the existing pipe so that the closed case divided into a plurality of pieces in the circumferential direction of the existing pipe surrounds a part of the existing pipe in an airtight state.
A cutting tool supported for rotating around the cutter axis, and having a plurality of cutting blades, is housed in the closed case,
(2) While rotating the cutting tool around the cutter axis,
(I) sending the cutting tool radially inward of the existing pipe to cut the existing pipe; and
(Ii) rotating the whole of the sealed case with the cutting tool in the circumferential direction of the existing pipe so that the cutting tool cuts the existing pipe over the entire circumference in the circumferential direction;
(3) By performing the steps (1) and (2) at two locations separated in the pipe axis direction, a section is generated,
(4) after surrounding the section and the sealed case with a tank, removing the section from the tank to generate a removed portion;
(5) Inserting the main piping element into the removed portion in a state where the endless connecting piping element in the pipe circumferential direction is mounted on the outer periphery of the main piping element;
(6) After the insertion, the connecting pipe element is slid to the existing pipe side so that the connecting pipe element straddles the main pipe element and the end of the existing pipe. Insertion method. After cutting a part of the existing pipe to generate a section, the section is removed, and the main pipe element is inserted into the removed portion from which the section has been removed, and the space between the main pipe element and the existing pipe is removed. In the uninterrupted water insertion method of joining with joining piping elements,
(1) The closed case is rotatably attached to the existing pipe so that the closed case divided into a plurality of pieces in the circumferential direction of the existing pipe surrounds a part of the existing pipe in an airtight state.
A cutting tool supported for rotating around the cutter axis, and having a plurality of cutting blades, is housed in the closed case,
(2) On at least one side of the sealed case, a force that pushes from the outside of the existing pipe toward the center of the existing pipe is applied to the existing pipe so that the cross-sectional shape of the existing pipe approaches a perfect circle. Then, the existing pipe is corrected by a pipe correction tool,
(3) While rotating the cutting tool around the cutter axis,
(I) sending the cutting tool radially inward of the existing pipe to cut the existing pipe; and
(Ii) In order for the cutting tool to cut the existing pipe over the entire circumference in the circumferential direction, in a state where the existing pipe is straightened, the entirety of the sealed case together with the cutting tool in the circumferential direction of the existing pipe. Rotate to
(4) By performing the above steps (1), (2) and (3) at two places separated in the tube axis direction, a section is generated,
(5) after surrounding the section and the sealed case with a tank, removing the section from the tank to generate a removed portion;
(6) Inserting the main piping element into the removed portion with the endless joining piping element mounted on the outer periphery of the main piping element in the pipe circumferential direction;
(7) After this insertion, the connecting pipe element is slid toward the existing pipe so that the connecting pipe element straddles the end of the main pipe element and the existing pipe,
Here, in the state where the existing pipe is straightened by the pipe straightening tool, the steps (5), (6) and (7) are carried out by a continuous water insertion method.

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