JP2002098289A - Method and device for flexibly expanding existing fluid pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and flexibly expand a fluid pipe without using a large sealed case and a cutting device, and to prevent the generation of damage of a packing between the fluid pipe and an equipment body. SOLUTION: An existing fluid pipe 1 is provided with a pair of equipment bodies 5 and 5 in right and left so that one of them slidingly-contacts with a guide sleeve 3 having the peripheral surface formed into a spherical body 3a for sealing, and a rotary sleeve 10 fitted on the peripheral surface of the opposite end is rotated so as to cut the fluid pipe 1 with a cutting tool 22 inserted form a working hole 17. With this structure, the fluid pipe can be flexibly expanded without using a large sealed case and a cutting device and without generating a damage of a packing between the fluid pipe and the equipment bodies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the expansion and contraction of an existing fluid pipe, such as a water pipe or a gas pipe, which can be cut and expanded without interrupting the flow of the internal fluid. The present invention relates to a flexible method and apparatus.

[0002]

2. Description of the Related Art Conventionally, fluid pipes buried in the ground are often subjected to stress in a direction perpendicular to the pipe or in a pipe axis direction due to relative displacement of the ground due to an earthquake, land subsidence, or the like. When the allowable limit is exceeded, the pipe may come off from the joint or a breakage accident may occur.

In order to prevent such an accident, it is effective to attach a flexible joint to an existing fluid pipe. As a general method of attaching this fitting without stopping the flow of the fluid in the fluid pipe, the flow is
For example, there is the following construction method.

[0004] That is, a sealed case is attached around the flow tube body in a watertight manner, a fluid pipe is cut into a ring shape by a cutter in the case, and the cut pieces are removed from the sealed case together with the cutting machine. This is performed by inserting a telescopic flexible joint into a closed case, fitting it into a cut portion of a fluid pipe, and finally removing the inside of the closed case from a flow tube.

[0005] In the above-mentioned conventional method of making the flow tube expandable and contractible, it is necessary to attach a large-sized closed case to the fluid pipe or to remove it after the work is completed. When the pipe diameter is large, it is necessary to use a heavy machine such as a crane, so that the operation becomes large, and there is a problem that the number of steps and operation costs increase.

Further, a cutting device having a cylindrical cutter having a larger outer diameter is used for cutting the fluid pipe. Therefore, when the pipe diameter is large, the cutting device is inevitably increased in size. Installation and removal work is complicated.

In order to solve the above-mentioned problems, the applicant of the present invention has made it possible to easily cut and expand a fluid pipe without using a large cutting device having a large sealed case and a cylindrical cutter. A method capable of flexing has been devised, and a patent application has been filed earlier (see Japanese Patent Application No. 11-119943).

[0008]

However, the above-mentioned prior application still has the following problems to be solved. That is, since the casing itself mounted on the fluid pipe via the packing is rotated together with the cutting device to cut the pipe, the packing may be damaged, so that it is difficult to select the material of the packing. There is.

If the outer peripheral surface of the fluid pipe is uneven due to corrosion or the like, it is not possible to maintain the watertightness of the packing, so it is necessary to repair the outer peripheral surface to a smooth surface. is there. Further, after cutting, the amount of flexibility of the fluid pipe is limited to the gap between the outer peripheral surface and both ends of the housing and the amount of expansion and contraction of the packing, so that a large relative displacement occurs in a direction directly supporting the pipe. May not be able to absorb it.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is possible to easily expand and contract a fluid pipe without using a large sealed case or a cutting device, and to provide a packing between a fluid pipe and a housing. It is an object of the present invention to provide a method and an apparatus for expanding and contracting an existing fluid pipe, which do not need to damage the fluid pipe or repair the outer peripheral surface of the fluid pipe, and have great flexibility.

[0011]

In order to achieve the above object, the present invention provides a method for expanding and contracting an existing fluid pipe, the method comprising the steps of: providing an outer peripheral surface of an existing fluid pipe with a cylindrical structure having a divided outer surface having a spherical outer surface; And a pair of left and right cylindrical housings of a divided structure separated by a required dimension in the pipe axis direction around the fluid pipe of the guide sleeve mounting part, while sealing the guide sleeve in a sealed manner. After the inner peripheral surface of the end is mounted on the spherical surface of the guide sleeve and the inner peripheral surface of the side end of the other housing is slidably and water-tightly slidably in contact with the outer peripheral surface of the fluid pipe, then the two housings are mounted. The cutting tool inserted through at least a part of the working hole in the outer peripheral surface of the fluid pipe is rotated while rotating the rotary sleeve fitted around the outer peripheral surface of the opposite end portion in the axial direction of the pipe with the movement thereof being restricted in the pipe axis direction. The fluid enclosed by both housings The intermediate portion is cut, by sealing the operation hole to remove the subsequent cutting tool is characterized in that elastic flexible the portion of the fluid pipe. According to the method of the above configuration, a pair of right and left casings is attached to the existing fluid pipe, and the fluid pipe is cut by rotating the rotary sleeve fitted to the outer peripheral surface of the opposite end. Without using a fluid pipe, the fluid pipe can be expanded and contracted and flexible, workability and work efficiency are improved, and damage to a seal member provided between the outer peripheral surface of the fluid pipe and the housing is prevented. .

By the above method, at least two of the fluid tubes
It is preferable to make the portion expandable and contractible. With this configuration, the tensile, compressive and bending moments acting on the fluid pipe are absorbed at at least two places, so that the effect of preventing the breakage of the fluid pipe is enhanced.

In the above method, a straight cylindrical guide sleeve is hermetically fixed to the outer peripheral surface of the fluid pipe facing the guide sleeve having a spherical surface, and the outer peripheral surface of the guide sleeve is fixed to the inner peripheral end of the other casing. It is preferable that the peripheral surfaces are brought into sliding contact. With this configuration, even if the outer peripheral surface of the fluid pipe with which the other casing is in sliding contact has an uneven surface, it is not necessary to repair it.

[0014] In the above method, it is preferable that the work of removing the cutting tool is performed while preventing the fluid from flowing out from the working hole of the rotating sleeve. This facilitates the work of removing the cutting tool.

In order to achieve the above object, the present invention provides an apparatus for expanding and contracting an existing fluid pipe, which comprises a cylindrical guide sleeve which is hermetically fixed to an outer peripheral face of the existing fluid pipe and has a spherical outer peripheral face. Are mounted on the circumference of the fluid pipe at a required distance from each other, and one side end inner peripheral surface is on the spherical surface of the guide sleeve, and the other side end inner peripheral surface is on the outer peripheral surface of the fluid pipe, respectively. A pair of left and right cylindrical housings having a split structure that slidably and slidably contact with each other, a rotating sleeve rotatably and hermetically fitted to outer peripheral surfaces of opposed ends of the two housings, and formed on the rotating sleeve. A cutting device attached to the opening of at least one of the working holes, and having a cutting tool capable of moving back and forth toward the center of the fluid pipe, rotation driving means for rotating the rotating sleeve, and after cutting the fluid pipe. In which the working hole is sealed And a means. According to the apparatus of the present invention having the above configuration, the operation cost is reduced because the apparatus has a small and simple configuration as compared with an apparatus used for a normal expansion / contraction / flexibility method.

In the above apparatus, the cutting tool is preferably an end mill. In this way, a relatively large diameter and thick fluid pipe can be easily cut.

In the above device, it is preferable to provide a gate valve device between the opening of the working hole and the cutting device. This facilitates removal of the cutting device and attachment of the sealing means for sealing the working hole.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. First, a telescopic flexible device of the present invention will be described with reference to FIGS. 1 is ground 2
An existing fluid pipe excavated and exposed over a required length, for example, a steel water pipe, and a pair of right and left steel guide sleeves each having a cylindrical shape having an upper and lower two-part structure are provided on an outer peripheral surface of an appropriate place. 3 and 4 are externally fitted with a predetermined distance from each other, and are welded to the outer peripheral surface of the water pipe 1 at both ends thereof and are hermetically fixed by welding upper and lower butted surfaces. .

The outer peripheral surface of the left guide sleeve 3 is formed as a spherical surface 3a centering on the tube axis, and annular stoppers 3b are provided at both left and right ends thereof. Further, the right guide sleeve 4 has a right cylindrical shape, and annular stoppers 4a are also connected to the outer peripheral surfaces at both left and right ends. Around a water pipe 1 between the left and right guide sleeves 3 and 4, a pair of left and right steel housings 5 each having a cylindrical shape having a vertically divided structure.
5 are externally fitted such that a required annular gap C is formed between the opposing surfaces, and an annular space S is also formed between the outer circumferential surface of the water pipe 1 and the upper and lower abutting surfaces. Are integrated by welding.

An outwardly facing short flange 5a is connected to the opposite end of each housing 5.

The inner peripheral surface of the left end of the left casing 5 is in sliding contact with the substantially middle portion of the spherical surface 3a of the left guide sleeve 3, and is inserted into the annular groove 6 formed at the left end of the casing 5. The packing 7 is pressed against the annular ring 8 and the plurality of bolts 9 screwed into the housing 5 to maintain the watertightness of the sliding contact surface between the guide sleeve 3 and the left housing 5. .

The inner peripheral surface of the right end of the right housing 5 is in sliding contact with the right end of the outer peripheral surface of the right guide sleeve 4 and is inserted into an annular groove 6 formed at the right end of the housing 5. 7
Is pressed by the annular ring 8 and the bolt 9 in the same manner as described above, the watertightness of the sliding contact surface between the guide sleeve 4 and the right housing 5 is maintained.

On the outer peripheral surface of the opposing ends of the left and right housings 5, a rotating sleeve 10 having an upper and lower two-part structure has a pair of annular grooves 11 on the inner peripheral surface thereof fitted to the flanges 5 a of both housings 5. The fitting is restricted by the movement in the axial direction of the tube and is rotatably fitted to the outside. The mounting flanges 10a formed on the mutually facing surfaces are integrated by fastening the bolts 12 and the nuts 13 to each other. I have.

A packing 15 is inserted into annular concave grooves 14 formed on the inner peripheral surfaces at both ends of the rotating sleeve 10, and the packing 15 is pressed by pressing rings 16 bolted to both side surfaces of the rotating sleeve. Thereby, the water tightness between the outer peripheral surfaces of the two housings 5 and the inner peripheral surface of the rotating sleeve 10 is maintained.

The packing 15 is preferably made of hard rubber or the like having a small sliding resistance with respect to the housing 5. As will be described later, the resistance when rotating the rotary sleeve 10 around the housing 5 is reduced, and the packing 15 is used. Damage such as kinking is prevented.

A work hole 17 having a diameter slightly smaller than an annular gap C formed on the opposing surfaces of the two housings 5 is formed in the center of the upper portion of the peripheral wall of the rotary sleeve 10. A valve device 18 and a cutting device 19 on the upper part thereof are hermetically mounted upward. The gate valve device 18 includes a valve body 20 that can open and close a pipe communicating with the working hole 17 and a moving mechanism 21 that moves the pipe 20 forward and backward in a direction orthogonal to the pipe by screw feed.

The cutting device 19 includes an end mill 22 that is a rotary cutting tool, a screw feed type elevating mechanism 23 that moves the end mill 22 toward and away from the center of the fluid pipe 1, and an end mill 22.
And a hydraulic motor 24 for rotating the motor.

Below the rotary sleeve 10 on the base plate 25 laid on the ground 2, both ends of a drive shaft 26 parallel to the tube axis are fixed by brackets 27, 27. Is a pair of drive sprockets 2
8, 28 are pivotally supported. The drive shaft 26 is rotated at a slow speed by attaching its left end to the rotation shaft 29a of the geared motor 29.

Mounting flange 1 on rotating sleeve 10
On the outer peripheral surface sandwiching Oa, four support shafts 30 parallel to the water pipe 1 are symmetrically fixed by brackets 31,
At both ends of each support shaft 30, driven sprockets 32 are non-rotatably mounted.

Each of the left and right driven sprockets 32 and the left and right driving sprockets 28 has a chain 3 respectively.
3 is wound around the rotating sleeve 10. Note that each chain 33 is formed in an endless shape by joining one end of each chain around each driven sprocket 32 and the driving sprocket 28 and then connecting both ends.

Both drive sprockets 29 are driven by the motor 29.
Is rotated to rotate each chain 33, and each driven sprocket 32 rotates together with the chain 33, so that the rotary sleeve 10 can rotate around the housing 5.

Next, a method of making the fluid pipe expandable and contractible by the above apparatus will be described. First, as described above, the left and right guide sleeves 3, 4, the housings 5, 5, and the rotating sleeve 10 are attached to the water pipe 1 excavated and exposed on the ground 2 in this order, and then both sides of the guide sleeves 3, 4 are provided. Water pipe 1
It is supported by a pair of left and right supports 34 erected on the base plate 25.

Next, a gate valve device 18 and a cutting device 19 are attached to the opening of the working hole 17 of the rotary sleeve 10, and then the base valve 25 below the rotary sleeve 10 is placed on the base plate 25.
Driving means such as a driving sprocket 28 and a motor 29 are installed, and a supporting shaft 30 and a driven sprocket 32 are mounted on the outer peripheral surface of the rotary sleeve 10. A chain 33 is wound around the sprockets 28 and 32.

In this state (the state shown in FIGS. 1 and 2), the end mill 22 is rotated by operating the hydraulic motor 24 and the handle (not shown) attached to the upper end of the lifting mechanism 23 is rotated. Water pipe 1
Down toward the top surface of the.

The upper end of the water pipe 1 is pierced by the end of the end mill 22, and at the same time, the motor 29 is operated to rotate the two chains 33 to rotate the rotary sleeve 10 once in a fixed direction. At this time, both sides of the rotating sleeve 10 are
It may be held by a guide roller or the like of a holding means separately attached to the water pipe 1 to prevent rattling in the pipe axis direction.

When the water pipe 1 is thick, the rotary sleeve 10 may be alternately rotated a plurality of times in the forward and reverse directions while the end mill 22 is fed stepwise to cut. When the rotary sleeve 10 is rotated as described above, the water pipe 1 is cut at the width of the outer diameter of the end mill 22 as shown in FIG.

After the water pipe 1 has been cut, the end mill 22 is raised above the valve element 20 of the gate valve device 18 by operating the elevator groove 23 of the cutting device 19 as shown in FIG. The valve body 20 is made to protrude by the above operation to seal the pipe line above the work hole 17.

Then, after the cutting device 19 is removed and a water stopcock mounting device (not shown) is mounted, the valve body 20 is opened, and as shown in FIG.
A water stopcock 35 is press-fitted therein and sealed. Then, the stopcock mounting device and the gate valve device 18 are removed, and the rotating sleeve 1 is removed.
The retaining plate 36 is fixed to the opening surface of the work hole 17 of the No. 0.

Finally, the drive means such as the support shaft 30, the driven sprocket 32, the chain 33, the drive sprocket 28 and the motor 29, the left and right supports 34 and the base plate 25, etc., which are attached to the outer peripheral surface of the rotary sleeve 10, are removed. Then, if the exposed water pipe 1 is backfilled, the construction is completed.

When a tensile force or a compressive force is applied to the water pipe 1 due to an earthquake or land subsidence, or a bending moment acts in a direction orthogonal to the pipe, as shown in FIG. The right side can relatively expand and contract between the guide sleeve 4 and the right housing 5, and the left housing 5 slidably in contact with the spherical surface 3 a of the left guide sleeve 3 is the guide sleeve. Since it can bend in either the left or right direction about the center 3, the stress acting on the water pipe 1 is absorbed and its breakage or the like is prevented.

Further, since the outer peripheral surface of the left guide sleeve 3 is formed as a spherical surface 3a to increase the flexibility of the water pipe 1, even if the relative displacement in the vertical direction or the like becomes large, the pipe may be damaged. There is no.

FIG. 7 shows an example in which two portions of the water pipe 1 are expanded and contracted and flexible in the manner described above. This way,
As shown in FIG. 8, the tension, compression force, bending moment, and the like acting on the water pipe 1 are absorbed at two places, and the expansion and contraction and flexibility of the water pipe 1 are further increased, so that the damage prevention effect is enhanced.

As described above, in the above embodiment, a pair of left and right casings 5 are attached to the water pipe 1, and the rotating sleeve 10 fitted on the outer peripheral surface of the opposite end is rotated and attached thereto. End mill 2 of cutting device 19
After the water pipe 1 is cut off by the step 2, the casing 5 and the rotary sleeve 10 are left as telescopic flexible joints as they are. Efficiency is greatly improved.

In addition, even if the pipe diameter is large, a large-sized sealed case and a cutting device are not required, so that there is no need to use a heavy machine such as a crane for mounting and removing the same, and the operation cost is reduced. Furthermore, since the cutting is performed using the end mill 22, the cutting load is small even for a large-diameter and thick-walled pipe, and therefore, a small-sized cutting device 19 can be used. As described above, the casing 5 is not rotated, and only the rotating sleeve 10 is rotated and cut. Therefore, the packing 7 interposed between the outer peripheral surface of the water pipe 1 and the casing 5 may be damaged. There is no.

The outer circumferential surface of one of the guide sleeves 3 fixed to the water pipe 1 by welding is formed into a spherical surface 3a, and the amount of flexibility is large, so that the relative displacement of the water pipe 1 in the vertical direction and the like is effectively absorbed, The damage prevention effect is also enhanced.

The present invention is not limited to the above-described embodiment.
A straight tubular guide sleeve 4 is fixed to the outer peripheral surface of the guide sleeve, but the guide sleeve 4 may be omitted and only the left and right stoppers may be provided.

That is, when the guide sleeve 4 is used, even if the outer peripheral surface of the water pipe 1 has an uneven surface due to corrosion or the like, the casing 5 can be fitted onto the guide sleeve 4 without repairing it. This has the advantage that the number of steps required for repair work can be reduced. However, when the outer peripheral surface of the water pipe 1 is a smooth surface and the packing 7 alone can maintain sufficient watertightness,
The guide sleep 4 becomes unnecessary.

When the fluid pipe such as the water pipe 1 has a large diameter, the gate valve device 18 and the cutting device 19 may be attached to the rotary sleeve 10 in plural numbers, for example, two at 180 degrees apart. In this case, only the rotation sleeve 10 needs to be rotated half a turn, so that the cutting efficiency is good, and the margin of the hydraulic hose or the like connected to the hydraulic motor 24 is short, and the piping is easy.

When the water pipe 1 is thin, a cutting tool such as a parting tool may be used in place of the end mill 22. In this case, a rotary actuator such as a hydraulic motor 24 becomes unnecessary.

In the above embodiment, a plurality of driven sprockets 32 are non-rotatably mounted on the outer peripheral surface of the rotary sleeve 10 and driven by a chain 33 to rotate the rotary sprocket 1.
0 is rotated, but a ring-shaped sprocket having an upper and lower two-part structure is detachably fixed to the left and right outer peripheral surfaces of the rotating sleeve 10, and the chain 33 is hung around the sprocket to rotate the rotating sleeve 10. You may do so.

[0051]

According to the present invention, the following effects can be obtained.

(A) According to the first aspect of the present invention, the fluid pipe can be cut and expanded and flexible without using a large sealed case or a cutting device, so that workability and work efficiency are greatly improved. I do. Further, since the rotating sleeve externally fitted to the housing is rotated, the packing provided between the outer peripheral surface of the fluid pipe and the housing is prevented from being damaged.

(B) According to the second aspect of the invention, since the tensile, compressive and bending moments acting on the fluid pipe are absorbed in at least two places, the effect of preventing the fluid pipe from being broken is enhanced.

(C) According to the third aspect of the invention, even if the outer peripheral surface of the fluid pipe with which the other housing slides is uneven, there is no need to repair it, and the number of steps is reduced. .

(D) According to the invention of claim 4, the work of removing the cutting tool becomes easy.

(E) According to the fifth aspect of the present invention, since the apparatus has a small size and a simple structure as compared with a device used in a normal expansion / contraction / flexibility method, the operation cost is reduced.

(F) According to the invention of claim 6, even a fluid pipe having a relatively large diameter and a thick wall can be easily cut.

(G) According to the invention of claim 7, removal of the cutting device and attachment of the sealing means for sealing the working hole become easy.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing a state before starting cutting of a fluid pipe in a device of the present invention.

FIG. 2 is a vertical sectional front view taken along the line II-II of FIG. 2;

FIG. 3 is a partially cutaway side view showing a state after the fluid pipe is cut.

FIG. 4 is a vertical cross-sectional side view showing a state in which the end mill is lifted after cutting and the pipeline of the working hole is closed by a gate valve.

FIG. 5 is a vertical sectional side view showing a state in which auxiliary devices such as a cutting device and a gate valve device are removed and a work hole is sealed.

FIG. 6 is a vertical sectional side view showing a state in which the fluid pipe is bent.

FIG. 7 is a vertical sectional side view showing a state where two portions of the fluid pipe are expanded and contracted and flexible.

FIG. 8 is a longitudinal sectional side view showing a state where it is bent at two places.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fluid pipe 2 Ground 3 Guide sleeve 3a Spherical surface 3b Annular stopper 4 Guide sleeve 4a Annular stopper 5 Housing 5a Flange 6 Annular groove 7 Packing 8 Annular ring 9 Bolt 10 Rotating sleeve 10a Mounting flange 11 Annular groove 12 Bolt 13 Nut 14 Annular groove 15 Packing 16 Pressing wheel 17 Working hole 18 Gate valve device 19 Cutting device 20 Valve element 21 Moving mechanism 22 End mill 23 Elevating mechanism 24 Hydraulic motor 25 Base plate 26 Drive shaft 27 Bracket 28 Drive sprocket 29 Geared motor 30 Support shaft 31 Bracket 32 driven sprocket 33 chain 34 support 35 water stopcock 36 retaining plate

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16L 27/12 F16L 55/00 C (72) Inventor Joji Kuroda 2-16-1, Shimbashi, Minato-ku, Tokyo No. 701 New Shimbashi Building Room 706 Cosmo Machinery Co., Ltd. In-house F-term (reference) 3C022 AA03 AA08 AA10 EE07 EE11 EE17 KK01 3H104 JA03 JA08 JA17 JB01 JD01 JD06 JD09 KB03 KB08 KB11 KB12 LA14 LA19 LF02 LG03 LG23

Claims (7)

[Claims] 1. A cylindrical guide sleeve having a divided structure having a spherical outer peripheral surface is fixed to an outer peripheral surface of an existing fluid pipe in a sealing manner, and is disposed around a fluid pipe of a guide sleeve mounting portion in a pipe axial direction. A pair of left and right cylindrical housings of a divided structure separated by a required dimension are formed such that the inner peripheral surface of the side end of one housing is the spherical surface of the guide sleeve and the inner peripheral surface of the side end of the other housing is a fluid pipe. The outer peripheral surfaces of the housings are slidably and water-tightly slidably attached to each other. While rotating, the cutting tool inserted from at least a part of the working hole on the outer peripheral surface is fed toward the center of the fluid pipe, thereby cutting the intermediate portion of the fluid pipe surrounded by both housings, and then the cutting tool By removing and sealing the working hole A method for making an existing fluid pipe expandable and contractible, wherein part of the body pipe is made elastic. 2. A method for expanding and contracting an existing fluid pipe according to claim 1, wherein at least two portions of the existing fluid pipe are expanded and contracted. 3. A straight cylindrical guide sleeve is hermetically fixed to the outer peripheral surface of the fluid pipe facing the guide sleeve having a spherical surface, and the inner peripheral surface of the side end of the other housing is fixed to the outer peripheral surface of the guide sleeve. 3. The method of making an existing fluid pipe expandable and contractable according to claim 1, wherein 4. The expansion and contraction flexibility of an existing fluid pipe according to claim 1, wherein the removal of the cutting tool is performed while preventing the fluid from flowing out from the working hole of the rotating sleeve. Method. 5. A cylindrical guide sleeve, which is hermetically fixed to the outer peripheral surface of an existing fluid pipe and has a spherical outer peripheral face, is mounted around the fluid pipe at a required distance from one another, and A pair of left and right cylindrical housings having a divided structure in which a side end inner peripheral surface is slidably and water-tightly slidably in contact with the spherical surface of the guide sleeve and the other side end inner peripheral surface is in contact with the outer peripheral surface of the fluid pipe. A rotating sleeve rotatably and hermetically fitted to the outer peripheral surfaces of the opposite ends of the two housings; a rotating sleeve attached to an opening of at least one working hole formed in the rotating sleeve; An existing fluid pipe, comprising: a cutting device having a cutting tool capable of moving forward and backward; rotating drive means for rotating the rotary sleeve; and sealing means for sealing the working hole after cutting the fluid pipe. Telescopic flexible device. 6. The apparatus according to claim 5, wherein the cutting tool is an end mill. 7. The expansion / contraction device for an existing fluid pipe according to claim 5, wherein a gate valve device is provided between the opening of the working hole and the cutting device.