Core and method for installing that core

Abstract

To provide a core and a method for installing the core so that the entire circumference of an opening to be sealed that is formed in a fluid pipe can be sealed.SOLUTION: A fluid pipe 1 comprises: a metal pipe 2 as a main pipe; and a rehabilitated pipe 3 as an inner pipe disposed along an inner circumferential surface of the metal pipe 2. A core 40 is inserted into and installed in a perforation 3a as an opening formed in at least the rehabilitated pipe 3 of the fluid pipe. The core comprises at least: a substantially cylindrical support member 41; and a downwardly protruding sealing portion 43 protruding from an outer circumferential side of the support member 41, for sealing the perforation 3a over an inner circumferential surface 3b.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a core inserted into a hole formed in at least an inner pipe portion of a fluid pipe including a main pipe portion and an inner pipe portion provided along the inner peripheral surface of the main pipe portion, and a method for installing the core.

Background Art

[0002] Conventional cores are inserted into holes to be sealed formed in a fluid pipe, and by expanding a substantially cylindrical support member constituting the core, an anticorrosion member provided on the outer periphery of the support member is brought into close contact with the inner peripheral surface of the hole, and there is one that seals the inner peripheral surface of the hole (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, as the support member is expanded in diameter, the anticorrosion member that bulges in the outer diameter direction is difficult to uniformly contact the inner peripheral surface of the hole formed along the pipe diameter of the rehabilitation pipe, and the internal stress generated by the close contact between the inner peripheral surface of the hole and the outer peripheral surface of the anticorrosion member becomes non-uniform, and there is a problem that fluid may enter a part between these peripheral surfaces.

[0005] The present invention has been made paying attention to such problems, and an object thereof is to provide a core capable of sealing the entire circumference of a hole to be sealed formed in a fluid pipe and a method for installing the core.

Means for Solving the Problems

[0006] In order to solve the above problems, the core of the present invention is A core that is inserted and installed in a hole formed at least in the inner pipe portion of a fluid pipe composed of the main pipe portion and the inner pipe portion provided along the inner peripheral surface of the main pipe portion, characterized by comprising at least a substantially cylindrical support portion and a protruding sealing portion that protrudes from the outer peripheral side of the support portion and seals the entire inner peripheral surface of the hole portion. According to this feature, by inserting the core into the hole portion of the inner pipe portion to be sealed in the fluid pipe and expanding the diameter of the substantially cylindrical support portion constituting the core, the protruding sealing portion protruding from the outer peripheral side of the support portion can be sealed to the entire inner peripheral surface.

[0007] The protruding sealing portion is characterized by being formed in an annular shape. According to this feature, by bringing the annular protruding sealing portion into close contact with the inner peripheral surface of the hole portion, the radial entry of the fluid in the pipe can be blocked.

[0008] The protruding sealing portion is characterized by being formed along the curved surface shape of the hole portion formed in the inner pipe portion. According to this feature, it is possible to reliably seal the hole portion having a curved surface shape corresponding to the pipe diameter of the inner pipe portion.

[0009] The protruding sealing portion is characterized by extending in a direction substantially orthogonal to the axis of the support portion. According to this feature, the protruding sealing portion is easy to manufacture and the versatility can be enhanced.

[0010] The protruding sealing portion is characterized by being formed so as to abut against the entire inner peripheral surface of the hole portion. According to this feature, the sealing performance by the protruding sealing portion can be enhanced.

[0011] It is further characterized by comprising a sealing portion that seals the inner peripheral surface of the branch portion of the main pipe portion communicating with the hole portion. According to this feature, the sealing region can be expanded between the hole portion formed in the inner pipe portion and the branch portion of the main pipe portion.

[0012] The method for installing the core of the present invention is as follows: A step of arranging an inner pipe portion along a pipeline on the inner peripheral surface of an existing main pipe portion; A step of forming a hole portion in the inner pipe portion; A step of inserting a core having at least a substantially cylindrical support portion and a protruding sealing portion protruding from the outer peripheral side of the support portion into the hole portion; It is characterized by having at least a step of expanding the core to seal the protruding sealing portion over the inner peripheral surface of the hole portion of the inner pipe portion. According to this feature, a core is inserted into a hole portion to be sealed in an inner pipe portion for regenerating the inner peripheral surface of an existing main pipe portion, and by expanding the diameter of the substantially cylindrical support portion constituting the core, the protruding sealing portion protruding from the outer peripheral side of this support portion can be sealed over the entire circumference of the inner peripheral surface.

[0013] The core further includes a sealing portion protruding from the outer peripheral side of the support portion, It is further characterized by having a step of expanding the core to seal the sealing portion over the inner peripheral surface of the branch portion of the main pipe portion. According to this feature, the sealing region can be expanded between the hole portion formed in the inner pipe portion and the branch portion of the main pipe portion.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Mode for Carrying Out the Invention

[0015] A mode for carrying out the core according to the present invention and a method for installing the core will be described below based on examples.

Examples

[0016] The core according to the embodiment of the present invention and the method for installing the core will be described with reference to FIGS. 1 to 12. In the following description, the surface along the pipe axis of the fluid pipe 1 in FIG. 2 will be described as the front side of the core 40.

[0017] As shown in Fig. 1, the fluid pipe 1 of this embodiment is composed of an existing metal pipe 2 as a main pipe portion formed in a substantially circular cross-sectional shape, and a regenerative pipe 3 in a substantially circular cross-sectional shape as an inner pipe portion provided along the inner peripheral surface of the existing metal pipe 2 to regenerate the inner peripheral portion of the existing metal pipe 2, and is a water pipe extending in a substantially horizontal direction. It is necessary to prevent the entry of fluid between the inner peripheral surface of the metal pipe 2 constituting the fluid pipe 1 and the outer peripheral surface of the regenerative pipe 3 in order to prevent rust and corrosion.

[0018] In addition, as long as the fluid pipe 1 is composed of a main pipe portion and an inner pipe portion provided in the inner peripheral portion thereof, the materials and uses of both pipe portions are not limited to those of this embodiment. For example, the main pipe portion is not limited to the metal pipe 2 made of ductile cast iron pipe having a substantially circular cross-sectional shape as in this embodiment, and may be other metal pipes such as cast iron, steel, or synthetic resin pipes such as concrete, vinyl chloride, polyethylene, or polyolefin. Also, the inner pipe portion is not limited to the regenerative pipe 3 made of FRP resin as in this embodiment, and may be a coating layer coated with epoxy resin, mortar, plating, etc. Further, in this embodiment, the fluid in the fluid pipe 1 is tap water, but the fluid flowing inside the fluid pipe is not necessarily limited to tap water. For example, in addition to industrial water, agricultural water, sewage, etc., it may be a liquid other than water, or a gas or a gas-liquid mixture of gas and liquid.

[0019] A branch port 2a is formed at a predetermined position of the existing metal pipe 2, and the lower end of a branch pipe 4 extending in the vertical direction branching upward from the metal pipe 2 is connected and fixed in a sealed state by welding around the branch port 2a. An upper flange 4a is formed to protrude in the outer diameter direction at the upper end of the branch pipe 4, and a repair valve 11 (see Fig. 11) described later is fixed by flange connection above the branch pipe 4, and an air valve 12 (see Fig. 11) is fixed by flange connection above the repair valve 11.

[0020] The rehabilitation pipe 3 is inserted into the metal pipe 2 while applying internal pressure and inverting a substantially cylindrical rehabilitation material impregnated with a liquid thermosetting resin in a water cutoff state of the metal pipe 2, and a process of supplying a mixed gas of steam and air or the like to the inside of the rehabilitation material and curing it by heat treatment is performed. As a result, it is arranged along the pipeline on the inner peripheral surface of the metal pipe 2, but the rehabilitation material does not enter the inside of the branch pipe 4 when inserted into the metal pipe 2. Therefore, when the rehabilitation pipe 3 is arranged along the pipeline on the inner peripheral surface of the existing metal pipe 2, the branch port 2a is blocked (see Fig. 1). Therefore, after arranging the rehabilitation pipe 3, it is necessary to form a hole in the pipe wall portion of the rehabilitation pipe 3 that blocks the branch port 2a by the punching device 50.

[0021] When forming a hole in the pipe wall of the rehabilitation pipe 3, as shown in Fig. 1, first, a short pipe 16 is connected to the upper flange 4a of the branch pipe 4 by bolts and nuts 15. Further, the base portion 17 of the punching device 50 is attached to the short pipe 16 by bolts 20. The punching device 50 includes a punching shaft 51 that extends in the vertical direction toward the fluid pipe 1 along the passages in the short pipe 16 and the branch pipe 4 and rotates around the axis, and a cutter member 52 fixed to the tip of the punching shaft 51 and having a punching blade 52a for punching through the fluid pipe 1. By rotating the handle 18, the cutter member 52 is moved downward through the male screw member 19 and the punching shaft 51 pivotally supported by the base portion 17 to form a hole 3a (see Fig. 2) in the pipe wall of the rehabilitation pipe 3.

[0022] In addition, in this embodiment, the hole 3a is formed by penetrating vertically through the upper top portion of the rehabilitation pipe 3 extending in a substantially horizontal direction. However, the direction of forming the hole is not limited to the vertical direction, and depending on the extending direction of the branch pipe, for example, it may be formed in the front or rear portion of the rehabilitation pipe 3 by forming it in the horizontal direction. The hole 3a is circular in plan view, and its inner peripheral surface 3b is formed along the curvature of the pipe wall of the rehabilitation pipe 3. Also, the diameter dimension of the hole 3a is smaller than the inner diameter dimension of the branch port 2a.

[0023] After the process of forming the hole 3a by the punching device 50 is completed, the cutter member 52 is pulled up into the short pipe 16 and the punching device 50 is removed. Then, instead of the punching device 50, a core installation device 10 shown in Fig. 2 is attached and a process of inserting a core 40 is performed.

[0024] (Core installation device) As shown in FIG. 2, the core installation device 10 mainly includes a shaft member 37 that extends in a retractable manner toward the inside of the fluid pipe 1 through a perforation 3a formed in the regeneration pipe 3, and an insertion holder 30 provided at the tip of the shaft member 37.

[0025] The shaft member 37 includes an outer cylinder portion 38 having a hollow cylindrical shape as a first shaft portion, and an inner cylinder portion 39 having a female screw portion 39a (see FIG. 5) that is fitted inside the outer cylinder portion 38 and screwed into a male screw portion 31a of the insertion holder 30 at the lower end, serving as a second shaft portion. The inner cylinder portion 39 is configured to be movable in the axial direction, that is, in the vertical direction, with respect to the outer cylinder portion 38 by using the hydraulic pressure supplied through a hydraulic port 65 of a hydraulic manifold 64 provided on a base portion 66.

[0026] As shown in FIGS. 3(a) and 3(b), the insertion holder 30 includes a central shaft 31 that extends in the vertical direction, a support portion 32 that is fitted on the upper outer periphery of the central shaft 31 and has a large-diameter flange portion 32a formed at the upper end, an elastically deformable elastic member 33 that is fitted below the support portion 32 on the outer periphery of the central shaft 31, and a pressing portion 34 that is fitted below the elastic member 33 on the outer periphery of the central shaft 31 and is relatively movable to sandwich the elastic member 33 between the pressing portion 34 and the support portion 32.

[0027] The central shaft 31 has a male screw portion 31a that is integrally formed at the upper end and screwed into a female screw portion 39a formed at the lower end of the inner cylinder portion 39 shown in FIG. 5, and a bulging portion 31b that bulges in the diameter-expanding direction is formed at the lower end. Then, as shown in FIG. 5, by screwing the male screw portion 31a of the central shaft 31 into the female screw portion 39a of the inner cylinder portion 39 to connect them, the support portion 32 is fixed to the outer cylinder portion 38, and the bulging portion 31b and the pressing portion 34 are provided with respect to the inner cylinder portion 39.

[0028] (Core) As shown in FIGS. 4(a) to 4(c), the core 40 is in close contact with the inner peripheral surface 3b of the perforation 3a formed by perforating the pipe wall of the rehabilitation pipe 3, on the perforated surface where the base material of the rehabilitation pipe 3 is exposed, and is used to prevent the entry of fluid between the inner and outer peripheral surfaces of the metal pipe 2 and the rehabilitation pipe 3 through the perforation 3a. More specifically, the core 40 is a substantially cylindrical body, and includes a support member 41 as a support portion having a circumferential wall that is substantially circular in plan view and has a through-hole formed therein, and a corrosion prevention member 42 made of an elastic material disposed on the outer peripheral surface of the support member 41. The support member 41 is made of a metal material such as stainless steel, titanium, or copper having corrosion resistance. Further, the corrosion prevention member 42 is made of a rubber or synthetic resin that is softer and more elastic than the support member 41, and is adhered to the outer peripheral surface of the support member 41 by an adhesive (not shown). Note that the materials of the support member or the corrosion prevention member constituting the core are not limited to the above materials. Further, the corrosion prevention member 42 may be thermally welded to the outer peripheral surface of the support member 41, for example.

[0029] The support member 41 is mainly composed of a lower small-diameter portion 41a and a large-diameter portion 41b that is continuous upward from the small-diameter portion 41a. A thick portion 41c that protrudes in the outer diameter direction is formed over the circumferential direction at a position slightly above the substantially central position in the vertical direction on the outer peripheral surface of the small-diameter portion 41a, which restricts the insertion of the large-diameter portion 41b into the perforation 3a and prevents the deformation of the corrosion prevention member 42. Further, the lower end edge 41d of the small-diameter portion 41a is formed in a curve along the peripheral edge of the perforation 3a of the rehabilitation pipe 3 (see FIGS. 4(a) and 4(b)).

[0030] The corrosion prevention member 42 is provided so as to cover the outer peripheral surface of the support member 41 with a plate thickness dimension substantially the same as that of the support member 41. Note that a thick portion 42a is formed between the thick portion 41c and the large-diameter portion 41b.

[0031] As described above, the core 40 composed of the support member 41 and the anticorrosion member 42 is mainly composed of a small-diameter lower cylindrical portion 40a and a large-diameter upper cylindrical portion 40b that is continuous upward from the lower cylindrical portion 40a, as shown in FIG. 4(c). A stepped portion 40c extending in the radial direction is formed between the lower cylindrical portion 40a and the upper cylindrical portion 40b. The lower cylindrical portion 40a has an outer diameter dimension that can be inserted into the branch pipe 4 and the perforation 3a, and the upper cylindrical portion 40b has an outer diameter dimension that can be inserted into the branch pipe 4 but cannot be inserted into the perforation 3a.

[0032] In addition, in this embodiment, the lower edge 41d of the support member 41, that is, the lower edge of the lower cylindrical portion 40a, is configured as a curve extending along the periphery of the perforation 3a according to the curvature of the rehabilitation pipe 3, but it does not necessarily have to be a curve along the periphery of the perforation 3a.

[0033] As shown in FIGS. 4(a) to 4(c), a lower protruding sealing portion 43 is formed in an annular shape over the circumferential direction on the outer peripheral surface 42b of the anticorrosion member 42 in the lower cylindrical portion 40a. The lower protruding sealing portion 43 is composed of a plurality (nine in this example) of protrusions 43a arranged adjacent to each other in the axial direction of the core 40. Each protrusion 43a is integrally formed in a substantially semicircular shape in a cross-sectional view continuous with the outer peripheral surface 42b of the anticorrosion member 42 and extends in a curved shape in the circumferential direction along the lower edge 41d of the support member 41. In this embodiment, as shown in FIGS. 6 and 7 to be described later, the first to fourth protrusions 43a from the bottom are arranged around the perforation 3a on the inner peripheral curved surface 3c of the rehabilitation pipe 3, and the fifth to seventh protrusions 43a from the bottom are arranged along the inner peripheral surface 3b of the perforation 3a of the rehabilitation pipe 3. The number of protrusions 43a arranged around the perforation 3a and on the inner peripheral surface 3b of the perforation 3a on the inner peripheral curved surface 3c of the rehabilitation pipe 3 can be variously changed according to the plate thickness dimension of the pipe wall of the rehabilitation pipe 3 and the like.

[0034] Further, the first ridge 43a from the bottom is formed at a position above the lower edge 41d of the support member 41. Between the lower edge 41d of the support member 41 and the first ridge 43a from the bottom, an insertion portion 45 is formed where the downward protruding sealing portion 43 does not protrude on the outer peripheral surface. The outer diameter dimension DG of the insertion portion 45 in the lower cylindrical portion 40a and the outer diameter dimension DM of the downward protruding sealing portion 43 are smaller than the outer diameter dimension DI of the perforation 3a, so that they can be inserted into the hole portion 3a. The outer diameter dimension DG of the insertion portion 45 is smaller than the outer diameter dimension DM of the downward protruding sealing portion 43 (DM > DG > DI). Therefore, when the core 40 is inserted into the perforation 3a as described later, the smaller-diameter insertion portion 45 is inserted first, and the larger-diameter downward protruding sealing portion 43 is inserted with the core 40 positioned with respect to the perforation 3a. That is, as the insertion progresses, the outer diameter dimension of the lower cylindrical portion 40a gradually increases. Therefore, the downward protruding sealing portion 43 can be guided while being centered with respect to the perforation 3a and inserted smoothly.

[0035] Also, on the upper part of the outer peripheral surface 42b of the anticorrosion member 42 in the upper cylindrical portion 40b, an upward protruding sealing portion 44 is formed in an annular shape extending in the circumferential direction. The upward protruding sealing portion 44 is composed of a plurality (four in this example) of ridges 44a arranged in parallel with a gap in the axial direction of the core 40. Each ridge 44a is integrally formed in a substantially semicircular shape in cross-section continuous with the outer peripheral surface 42b of the anticorrosion member 42, and has a larger axial width dimension and a larger radial protruding dimension than the ridge 43a of the downward protruding sealing portion 43, and extends linearly in the direction along the upper edge 41e of the support member 41, that is, in the circumferential direction of the core 40. Further, in this embodiment, all the ridges 44a are capable of contacting the inner peripheral surface 4c (see FIG. 5) of the branch pipe 4.

[0036] In this way, due to the small wall thickness dimension of the inner peripheral surface 3b of the perforation 3a of the regenerative pipe 3, each ridge 43a of the downward protruding sealing portion 43 is smaller than the ridge 44a of the upward protruding sealing portion 44 and is arranged close to each other. On the other hand, each ridge 44a of the upward protruding sealing portion 44 can be pressure - contacted over a wide axial range with respect to the inner peripheral surface 4c of the branch pipe 4, so it is larger than the ridge 43a and can be arranged at a small number and spaced apart. Therefore, the structure can be simplified while enhancing the sealing performance. Note that the ridge 44a may be made smaller than the ridge 43a, arranged closer, or increased in number. Also, it is not necessary for all the ridges 44a to contact the inner peripheral surface 4c.

[0037] (Installation process of the core into the perforation) Next, the installation process of the core 40 into the perforation 3a by the core installation device 10 will be described. As shown in FIG. 1, after the process of drilling the perforation 3a in the fluid pipe 1 by the drilling device 50 is completed, as shown in FIG. 2, the core 40 is inserted and attached to the outer peripheral surface of the insertion holder 30 from below. Next, the insertion holder 30 with the core 40 attached is inserted into the short pipe 16 and the branch pipe 4, and the base portion 66 of the core installation device 10 is connected above the short pipe 16. Then, by the rotation operation of the handle 61 of the core installation device 10, the core 40 attached to the outer peripheral surface of the insertion holder 30 is moved downward in the branch pipe 4 and inserted into the perforation 3a. Note that at the time of insertion, since the insertion portion 45 with a small diameter is inserted first and the core 40 is positioned with respect to the perforation 3a, and then the downward protruding sealing portion 43 with a large diameter is inserted, the downward protruding sealing portion 43 can be guided while aligning with the perforation 3a and inserted smoothly.

[0038] As shown in FIG. 5, in the state where the lower cylindrical portion 40a of the core 40 is inserted and arranged in the perforation 3a, on the inner peripheral surface 3b of the perforation 3a where the base of the regenerative pipe 3 is exposed, in this embodiment, the 5th to 7th ridges 43a from the bottom in the downward protruding sealing portion 43 face each other in the circumferential direction with a gap S1 therebetween, and a part of the lower cylindrical portion 40a of the core 40 protrudes inward from the perforation 3a into the regenerative pipe 3. Also, on the inner peripheral surface 4c of the branch pipe 4, each ridge 44a of the upward protruding sealing portion 44 of the upper cylindrical portion 40b of the core 40 faces each other in the circumferential direction with a gap S2 therebetween.

[0039] Next, after inserting the core 40 into the perforation 3a, a hydraulic oil is supplied in an appropriate amount through a hydraulic pipe (not shown) connected to the hydraulic port 65 (see FIG. 2). As shown in FIGS. 6 and 7, the inner cylinder portion 39 is moved upward with respect to the outer cylinder portion 38, so that the pressing portion 34 is moved upward with respect to the support portion 32, and the elastic member 33 is clamped between the pressing portion 34 and the support portion 32 and elastically deformed in the diametrically expanding direction.

[0040] As shown in FIGS. 6 and 7, the lower cylinder portion 40a of the core 40 is pushed and expanded in the outer diameter direction of the core 40 by the elastically deformed elastic member 33, and thus the diameter is expanded. The portion of the lower cylinder portion 40a facing the perforation 3a is pressed against the inner peripheral surface 3b over the circumferential direction, and the portion of the lower cylinder portion 40a protruding below the perforation 3a is bent toward the outer diameter side over the circumferential direction.

[0041] Also, the upper three ridges 43a of the lower protruding seal portion 43 formed on the lower cylinder portion 40a of the core 40 are strongly pressed against the inner peripheral surface 3b of the perforation 3a. Since these ridges 43a extend in a curved shape over the inner peripheral surface 3b of the perforation 3a, the inner peripheral surface 3b of the perforation 3a is continuously sealed over the entire circumference. Note that, since the thick portion 41c is provided on the outer periphery of the upper portion of the support member 41, the elastic deformation of the upper portion of the elastic member 33 in the diametrically expanding direction is restricted. Therefore, by gradually elastically deforming the elastic member 33 from the vicinity of the lower side of the thick portion 41c toward the lower end side elastic member 33, an external force for pressing against the inner peripheral surface 3b of the perforation 3a can be surely applied.

[0042] Also, the lower four ridges 43a of the lower protruding seal portion 43 formed on the lower cylinder portion 40a of the core 40 are strongly pressed against the periphery of the perforation 3a on the inner peripheral curved surface 3c of the regeneration pipe 3. Since these ridges 43a extend annularly along the perforation 3a, the inner peripheral curved surface 3c around the perforation 3a is sealed over the entire surface. Note that, since the upper end portion of the thick portion 42a in the core 40 is supported by the large-diameter flange portion 32a formed on the support portion 32, and the upward movement of the core 40 is restricted, an external force for bending the lower cylinder portion 40a toward the inner peripheral curved surface 3c of the regeneration pipe 3 by the elastic member 33 can be surely applied.

[0043] The elastic member 33 has an elastic deformation allowance that allows for sufficient elastic deformation in the diametrical expansion direction up to the location where it sandwiches the lower cylindrical portion 40a of the core 40 that is bent between the inner peripheral surface 3c of the regenerative pipe 3 surrounding the perforation 3a. Thus, the elastically deformed elastic member 33 can apply an external force that bends the lower cylindrical portion 40a of the core 40 so as to be in close contact with the inner peripheral surface 3c of the regenerative pipe 3.

[0044] By deforming the elastic member 33 in this way, the upper part of the downward protruding sealing portion 43 of the lower cylindrical portion 40a in the core 40 is pressed against the inner peripheral surface 3b of the perforation 3a, the lower part of the downward protruding sealing portion 43 of the lower cylindrical portion 40a is pressed against the periphery of the perforation 3a on the inner peripheral surface 3c of the regenerative pipe 3, and the stepped portion 40c is pressed against the upper part of the peripheral edge of the perforation 3a on the outer peripheral surface of the regenerative pipe 3. That is, the anticorrosion member 42 of the core 40 is pressed against the entire circumference of the inner peripheral surface 3b of the perforation 3a, and further continuously against the inner peripheral surface 3c and the outer peripheral surface 3d of the regenerative pipe 3 surrounding the perforation 3a. As a result, the peripheral edge portion of the perforation 3a in the regenerative pipe 3 is clamped from the inner and outer sides in the radial direction by the lower cylindrical portion 40a and the stepped portion 40c of the core 40. Therefore, the core 40 is stably installed in the perforation 3a, and it is possible to prevent the fluid in the fluid pipe 1 from entering between the inner peripheral surface of the metal pipe 2 and the outer peripheral surface 3d of the regenerative pipe 3. Also, it is possible to prevent the fluid in the fluid pipe 1 from entering the inside of the regenerative pipe 3 through the inner peripheral surface 3b of the perforation 3a where the base material of the regenerative pipe 3 is exposed.

[0045] In addition, since the downward protruding sealing portion 43 is composed of a plurality of protrusions 43a, the surface area increases, and each protrusion 43a is more likely to deform when pressed compared to the case where the downward protruding sealing portion 43 is composed of a single protrusion. Therefore, even if the inner peripheral surface 3b of the perforation 3a is rough due to the perforation by the cutter member 52, a high sealing performance can be maintained while being in close contact with the inner peripheral surface 3b. In particular, when each protrusion 43a elastically deforms, it is easier to deform using the gap 43b (see FIG. 4) between adjacent protrusions 43a as the deformation allowance, so the sealing performance can be enhanced. Also, even if any one of the plurality of protrusions 43a deforms, it is difficult for the other protrusions 43a to be affected due to the gap 43b, so each protrusion 43a can maintain a high sealing performance.

[0046] After the core 40 is completely installed in the perforation 3a, the inner cylinder part 39 is hydraulically moved downward relative to the outer cylinder part 38 to elastically restore the elastic member 33. At the same time, by the reverse rotation operation of the handle 61 (see FIG. 2) of the feed shaft 63, leaving the core 40 installed in the perforation 3a, only the insertion holder 30 is moved upward to the inside of the short pipe 16 (see FIG. 8).

[0047] Next, the base part 66 of the core installation device 10 is temporarily removed from the short pipe 16. As shown in FIG. 9, a support part 32, which is a part of the attachment of the insertion holder 30, is replaced with a separate support part 32c having a different shape. A new insertion holder 30A to which the support part 32c is attached is inserted into the short pipe 16 and the branch pipe 4, and the base part 66 of the core installation device 10 is connected above the short pipe 16. Then, by the rotation operation of the handle 61 (see FIG. 2) of the feed shaft 63, the insertion holder 30A is moved downward and inserted into the core 40 installed in the perforation 3a from above. As shown in FIG. 10(a), the downward movement stops at the position where the lower end of the support part 32c of the insertion holder 30A abuts against the upper edge 41e of the core 40.

[0048] Next, by the hydraulic oil supplied in an appropriate amount through a hydraulic pipe (not shown) connected to the hydraulic port 65 (see FIG. 2), as shown in FIG. 10(b), the inner cylinder part 39 is moved upward relative to the outer cylinder part 38, so that the pressing part 34 is moved upward relative to the support part 32c, and a step of sandwiching the elastic member 33 between the pressing part 34 and the support part 32c and elastically deforming it in the diametrically expanding direction is performed.

[0049] By this step, the upper part of the upper cylinder part 40b of the core 40 is pushed and expanded in the outer diameter direction from the inside of the core 40 by the elastically deformed elastic member 33 and expands in diameter. Each ridge 44a of the upper protruding sealing part 44 formed on the upper part of the upper cylinder part 40b is strongly pressed against the inner peripheral surface 4c of the branch pipe 4, so that the inner peripheral surface 4c of the branch pipe 4 is continuously sealed in the circumferential direction.

[0050] In this way, the lower protruding sealing portion 43 of the lower cylindrical portion 40a of the core 40 is pressed against the inner peripheral surface 3b and the inner peripheral curved surface 3c of the perforation 3a formed in the regeneration pipe 3, and the upper protruding sealing portion 44 of the core 40 is pressed against the inner peripheral surface 4c of the branch pipe 4. As a result, the gap S2 generated between the core 40 and the branch pipe 4 is sealed, preventing fluid from entering from the branch pipe 4 side between the inner peripheral surface of the metal pipe 2 and the outer peripheral surface 3d of the regeneration pipe 3.

[0051] Next, the inner cylinder portion 39 is moved downward with respect to the outer cylinder portion 38 by hydraulic pressure to elastically restore the elastic member 33. Then, by rotating the handle 61 (see FIG. 2) of the feed shaft 63 in the reverse direction, leaving the core 40 installed in the perforation 3a and the branch pipe 4, only the insertion holder 30A is moved to the inside of the upper short pipe 16, and the core installation device 10 is removed from the short pipe 16, completing the installation work of the core 40.

[0052] Then, as shown in FIG. 11, after removing the short pipe 16 from the branch pipe 4, the repair valve 11 is hermetically connected above the branch pipe 4, and the air valve 12 is hermetically connected above the repair valve 11, restoring the pipeline.

[0053] As shown in FIG. 12, when the fluid fills the regeneration pipe 3 and the branch pipe 4 with the restoration of the pipeline, due to the pressure from the fluid (see the white arrow in the figure), the upper ridge 43a of the lower protruding sealing portion 43 is pressed against the inner peripheral surface 3b of the perforation 3a, preventing the entry of fluid between the lower protruding sealing portion 43 and the inner peripheral surface 3b of the perforation 3a, and the lower ridge 43a is pressed against the inner peripheral curved surface 3c. Also, since the stepped portion between the small-diameter portion 41a and the large-diameter portion 41b of the support member 41 is pressed downward, the stepped portion 40c is pressed against the outer peripheral surface 3d of the regeneration pipe 3. Further, each ridge 44a of the upper protruding sealing portion 44 is pressed against the inner peripheral surface 4c of the branch pipe 4, preventing the entry of fluid between the upper protruding sealing portion 44 and the inner peripheral surface 4c of the branch pipe 4, thus sealing the gap S2 between the core 40 and the branch pipe 4 and preventing fluid from entering between the inner peripheral surface of the metal pipe 2 and the outer peripheral surface 3d of the regeneration pipe 3.

[0054] (Function and Effect) As described above, the core 40 as an embodiment of the present invention is inserted and installed in at least the perforation 3a formed as a hole in the regeneration pipe 3 of the fluid pipe 1, which is composed of the metal pipe 2 as the main pipe portion and the regeneration pipe 3 as the inner pipe portion provided along the inner peripheral surface of the metal pipe 2, and includes at least a substantially cylindrical support member 41 and a downward protruding sealing portion 43 that protrudes from the outer peripheral side of the support member 41 and seals the entire inner peripheral surface 3b of the perforation 3a. According to this, by inserting the core 40 into the perforation 3a of the regeneration pipe 3 to be sealed in the fluid pipe 1 and expanding the diameter of the substantially cylindrical support member 41 constituting the core 40, the downward protruding sealing portion 43 protruding from the outer peripheral side of the support member 41 can be sealed over the entire circumference of the inner peripheral surface 3b.

[0055] In addition, since the plurality of protrusions 43a of the downward protruding sealing portion 43 are formed in an annular shape, the annular downward protruding sealing portion 43 is continuously and closely attached to the inner peripheral surface 3b of the perforation 3a in the circumferential direction, so that the radial entry of the fluid in the pipe can be blocked.

[0056] Moreover, since the plurality of protrusions 43a of the downward protruding sealing portion 43 are formed in an annular shape along the curved surface shape of the inner peripheral surface 3b of the perforation 3a formed in the regeneration pipe 3, the perforation 3a having a curved surface shape corresponding to the pipe diameter of the regeneration pipe 3 can be reliably sealed.

[0057] More specifically, since the inner peripheral surface 3b of the perforation 3a is formed in a three-dimensional curved surface shape as shown in FIGS. 6 and 7, when the plurality of protrusions are extended in a direction substantially orthogonal to the axis of the core 40, each protrusion deviates in the middle of the circumferential direction on the inner peripheral surface 3b of the perforation 3a depending on the pipe diameter of the regeneration pipe 3 (see FIGS. 14 and 15). On the contrary, since the protrusion 43a of the present embodiment is formed along the curved surface shape of the inner peripheral surface 3b, each protrusion 43a continuously contacts the inner peripheral surface 3b in the circumferential direction, so that even if the wall thickness dimension of the pipe wall is small, it can be reliably sealed to prevent the entry of fluid. Furthermore, since the plurality of protrusions 43a of the downward protruding sealing portion 43 are in contact with substantially the entire surface of the inner peripheral surface 3b of the perforation 3a, the sealing performance is further improved.

[0058] The protrusion 43a preferably extends substantially parallel to the periphery of the perforation 3a. However, as long as at least one of the plurality of protrusions 43a is in continuous contact along the circumferential direction along the curved surface shape of the inner peripheral surface 3b of the perforation 3a, it is not necessarily required that all the protrusions 43a extend substantially parallel to the periphery of the perforation 3a. Further, for example, the protrusion may be formed in a wavy shape that extends continuously in the circumferential direction while meandering in the axial direction of the core 40.

[0059] Further, by further providing an upper protruding sealing portion 44 that seals across the inner peripheral surface 4c of the branch pipe 4 of the metal pipe 2 communicating with the perforation 3a, the sealing region can be expanded between the perforation 3a formed in the rehabilitation pipe 3 and the branch pipe 4 that is the branching portion of the metal pipe 2. That is, by expanding the sealing region from the perforation 3a to the branch pipe 4 above it, not only is the inner peripheral surface 3b of the perforation 3a sealed by the lower protruding sealing portion 43, but also the vicinity around the perforation 3a on the outer peripheral surface 3d of the rehabilitation pipe 3 is covered by the gap S2 that becomes the sealing region (see FIGS. 6 and 7). Therefore, the sealing performance of the inner peripheral surface 3b of the perforation 3a is further improved.

[0060] Further, the method for installing the core 40 as an embodiment of the present invention includes a step of arranging the rehabilitation pipe 3 along the inner peripheral surface of the existing metal pipe 2 along the pipeline, a step of forming a perforation 3a in the rehabilitation pipe 3 (see FIG. 1), and inserting into the perforation 3a a core 40 that includes at least a substantially cylindrical support member 41 and a lower protruding sealing portion 43 that protrudes from the outer peripheral side of the support member 41 and seals across the inner peripheral surface 3b of the perforation 3a (see FIG. 5), and a step of expanding the diameter of the core 40 to seal the lower protruding sealing portion 43 across the inner peripheral surface 3b of the perforation 3a of the rehabilitation pipe 3 (see FIGS. 6 and 7). According to this, by inserting the core 40 into the perforation 3a of the rehabilitation pipe 3 to be sealed in the fluid pipe 1 and expanding the diameter of the substantially cylindrical support member 41 that constitutes the core 40, the lower protruding sealing portion 43 protruding from the outer peripheral side of the support member 41 can be sealed across the entire circumference of the inner peripheral surface 3b.

[0061] Further, the core 40 further includes an upward protruding sealing portion 44 protruding from the outer peripheral side of the support member 41. By further expanding the diameter of the core 40 and performing a process of sealing the upward protruding sealing portion 44 across the inner peripheral surface 4c of the branch pipe 4 (see FIG. 10), the sealing region can be expanded between the perforation 3a formed in the regeneration pipe 3 and the branch pipe 4. Specifically, not only the entry of fluid from between the downward protruding sealing portion 43 and the inner peripheral surface 3b of the perforation 3a is prevented, but also the entry of fluid from between the upward protruding sealing portion 44 and the inner peripheral surface 4c of the branch pipe 4 is prevented. As a result, the sealing region expands from the perforation 3a to the branch pipe 4 above it, and the vicinity around the perforation 3a on the outer peripheral surface 3d of the regeneration pipe 3 is covered by the gap S2 that becomes the sealing region. Therefore, the entry of fluid between the inner peripheral surface of the metal pipe 2 and the outer peripheral surface 3d of the regeneration pipe 3 is prevented (see FIG. 12).

[0062] As described above, the embodiments of the present invention have been described with reference to the drawings. However, the specific configuration is not limited to these embodiments, and modifications and additions within the scope not departing from the gist of the present invention are also included in the present invention. In the following modification examples, the same parts and configurations as those in the above embodiments are denoted by the same reference numerals, and detailed descriptions thereof are omitted.

[0063] For example, in the above embodiment, the downward protruding sealing portion as the protruding sealing portion is exemplified as being constituted by a plurality of ridges 43a provided in the axial direction of the core 40. However, the present invention is not limited to this. For example, like the core 40A as a modification example shown in FIG. 13, the downward protruding sealing portion 43A as the protruding sealing portion may be constituted by one ridge 143a formed wide in the vertical direction so as to be in close contact with substantially the entire inner peripheral surface 3b of the perforation 3a. Thereby, the sealing performance can be enhanced. Further, the width dimension and the cross-sectional shape of the ridge are not limited to those of the ridge 43a in the above embodiment, and may be formed in a substantially trapezoidal shape that is wide in the radial direction of the regeneration pipe 3 like the ridge 143a as a modification example. The width dimension, cross-sectional shape, size, etc. can be variously changed.

[0064] In addition, in the above embodiment, the form in which the lower protruding sealing portion as the protruding sealing portion is formed along the curved surface shape of the inner peripheral surface 3b of the perforation 3a is exemplified. However, the present invention is not limited to this. For example, like the cores 40B and 40C as modified examples shown in FIGS. 14 and 15, each ridge 43a of the lower protruding sealing portion 43B as the protruding sealing portion may extend in a direction substantially orthogonal to the axis of the support member 41. By doing so, the structure of the ridge 43a is simplified and it becomes easier to manufacture, so that the versatility can be enhanced. Further, the lower protruding sealing portion 43B can be in close contact with substantially the entire inner peripheral surface 3b of the perforation 3a, thereby further enhancing the sealing performance. Furthermore, even when the ridge 43a extends in a direction substantially orthogonal to the axis of the support member 41 as described above, the sealing performance can be further enhanced by extending at least one of the plurality of ridges 43a so as to be in continuous contact with the inner peripheral surface 3b of the perforation 3a in the circumferential direction.

[0065] Regarding the upper protruding sealing portion 44 as the sealing portion as well, similar to the lower protruding sealing portion, the upper protruding sealing portion 44A may be constituted by a single ridge 144a. Further, the width dimension and the cross-sectional shape of the ridge are not limited to those of the ridge 44a in the above embodiment, and may be formed in a substantially trapezoidal shape that is wide in the axial direction of the core 40 like the ridge 144a as a modified example, and the width dimension, cross-sectional shape, size, etc. can be variously changed.

[0066] Furthermore, the lower protruding sealing portion as the protruding sealing portion and the upper protruding sealing portion as the sealing portion do not necessarily have to be configured in the same manner. For example, the lower protruding sealing portion may be constituted by a plurality of ridges 43a as in the above embodiment, and the upper protruding sealing portion may be constituted by a ridge 144a as in the above modified example. Also, as long as at least the protruding sealing portion is formed, the sealing portion does not necessarily have to be formed.

[0067] In addition, in the above-described embodiment, an example is given in which the main pipe portion is constituted by an existing metal pipe 2 and the inner pipe portion is constituted by a recycled pipe 3. However, the present invention is not limited thereto. For example, as shown in FIG. 13, the inner pipe portion may be composed of an existing metal pipe 2 and a recycled pipe 3 provided inside thereof, and the main pipe portion may be constituted by an upper split body 103 (split T-shaped pipe) and a lower split body (not shown) that are externally fitted to the upper and lower outer circumferences of the metal pipe 2. And in this case, the lower protruding sealing portion 43A as the protruding sealing portion may be sealed in the circumferential direction on the inner circumferential surface 102b of the perforation 102a of the metal pipe 2 and the inner circumferential surface 3b of the perforation 3a of the recycled pipe 3. Thus, the main pipe portion and the inner pipe portion may be constituted by one pipe portion or may be constituted by a plurality of pipe portions.

[0068] In addition, in the above-described embodiment, an example is given in which a step of inserting and installing the core 40 into the perforation 3a as a hole formed in the recycled pipe 3 as the inner pipe portion with the metal pipe 2 in a water cutoff state is performed. However, the present invention is not limited thereto, and a step of inserting and installing the core 40 into the perforation 3a may be performed with the metal pipe 2 in a non-water cutoff state. For example, as shown in FIG. 13, when the main pipe portion is constituted by an upper split body 103 (split T-shaped pipe) and a lower split body (not shown) that are externally fitted to the upper and lower outer circumferences of the metal pipe 2, a working valve (not shown) is connected in a sealed state between the upper flange 4a of the branch pipe 4 and the short pipe 16, and the recycled pipe 3 and the metal pipe 2 as the inner pipe portion are kept in a non-water cutoff state, and steps of forming the perforations 3a and 102a or inserting and installing the core 40A into the perforations 3a and 102a may be performed.

[0069] In addition, in the above-described embodiment, an example is given in which the upper protruding sealing portion 44 as the sealing portion is integrally formed on the outer circumferential surface 42b of the anticorrosion member 42. However, the present invention is not limited thereto. As the upper protruding sealing portion 44B of the core 40B as a modified example shown in FIGS. 14(a) and (b), a packing 47B, or as the upper protruding sealing portion 44C of the core 40C as a modified example shown in FIGS. 15(a) and (b), a packing 47C, it may be constituted by a sealing member or the like that is formed separately from the anticorrosion member 42 and is housed in an annular recess 46 formed in the circumferential direction on the outer circumference of the upper cylinder portion 40b.

[0070] In the above embodiment, the core 40 is exemplified as being composed of a support member 41 and a corrosion prevention member 42 disposed on its outer periphery. However, the present invention is not limited to this, and as long as it includes at least a substantially cylindrical support portion and a protruding sealing portion that protrudes from the outer peripheral side of the support portion and seals the inner peripheral surface of the hole portion, the protruding sealing portion may protrude only from the lower part of the outer periphery of the support member 41. That is, the corrosion prevention member 42 does not necessarily have to be provided over the entire outer peripheral surface of the support member 41.

[0071] In the above embodiment, the form in which the first to fourth ridges 43a from the bottom of the lower protruding sealing portion 43 are pressed against the periphery of the perforation 3a on the inner peripheral curved surface 3c of the rehabilitation pipe 3 is exemplified. However, the present invention is not limited to this, and as long as it has ridges 43a arranged at least along the inner peripheral surface 3b of the perforation 3a, it does not necessarily have to have ridges that are pressed against the periphery of the perforation 3a on the inner peripheral curved surface 3c of the rehabilitation pipe 3. Also, as in the above embodiment, since the lower protruding sealing portion 43 is composed of a plurality of ridges 43a, any one of these plurality of ridges 43a can be brought into close contact with the perforations of various rehabilitation pipes corresponding to different curvatures, that is, different pipe diameters, so the versatility is high.

[0072] In the above embodiment, the ridges 43a of the lower protruding sealing portion 43 as the protruding sealing portion and the ridges 44a of the upper protruding sealing portion 44 as the sealing portion are exemplified as being formed in an annular shape so as to be in close contact with the inner peripheral surface 3b of the perforation 3a in the circumferential direction. However, the present invention is not limited to this, and it does not necessarily have to be formed in an annular shape. For example, a plurality of linear ridges may be arranged so as to overlap each other in the axial direction. Furthermore, a plurality of convex portions may be formed.

[0073] In the above embodiment, the form in which the insertion holder 30 is applied as a means for expanding the diameter of the substantially cylindrical support member 41 constituting the core is exemplified. However, the present invention is not limited to this, and the core may be expandable by a diameter expanding means other than the insertion holder 30.

Explanation of Reference Numerals

[0074] 1 Fluid pipe 2 Metal pipe (this pipe part) 2a Branch port 3 Regenerated pipe (inner pipe part) 3a Perforation (hole part) 3b Inner peripheral surface 3c Inner peripheral curved surface 3d Outer peripheral surface 4 Branch pipe 4c Inner peripheral surface 10 Core installation device 30, 30A Insertion holder 40 Core 40A~40C Core 40a Lower cylindrical part 40b Upper cylindrical part 40c Step part 41 Support member (support part) 41d Lower end edge 41e Upper end edge 42 Anti-corrosion member 43, 43A Lower protruding sealing part (protruding sealing part) 43a Ridge 44 Upper protruding sealing part (sealing part) 44A~44C Upper protruding sealing part 44a Ridge 47B, 47C Packing 50 Perforation device 102a Perforation 102b Inner peripheral surface 103 Upper split body 143a, 144a Ridge

Claims

1. A core that is inserted and installed in a hole formed at least in the inner pipe portion of a fluid pipe composed of the main pipe portion and the inner pipe portion provided along the inner peripheral surface of the main pipe portion, characterized by comprising at least a substantially cylindrical support portion and a protruding sealing portion that protrudes from the outer peripheral side of the support portion and seals across the inner peripheral surface of the hole portion.

2. The core according to claim 1, wherein the protruding sealing portion is formed in an annular shape.

3. The core according to claim 1, wherein the protruding sealing portion is formed along the curved surface shape of the hole portion formed in the inner pipe portion.

4. The core according to claim 1, wherein the protruding sealing portion extends in a direction substantially orthogonal to the axis of the support portion.

5. The core according to claim 1, wherein the protruding sealing portion is formed so as to contact the entire inner peripheral surface of the hole portion.

6. The core according to any one of claims 1 to 5, further comprising a sealing portion that seals across the inner peripheral surface of a branch portion of the main pipe portion communicating with the hole portion.

7. A step of disposing the inner pipe portion along a pipeline on the inner peripheral surface of an existing main pipe portion; A step of forming a hole portion in the inner pipe portion; A step of inserting a core comprising at least a substantially cylindrical support portion and a protruding sealing portion protruding from the outer peripheral side of the support portion into the hole portion; A method for installing a core, characterized by comprising at least a step of expanding the core to seal the protruding sealing portion across the inner peripheral surface of the hole portion of the inner pipe portion.

8. The core further comprises a sealing portion protruding from the outer peripheral side of the support portion, The method for installing a core according to claim 7, further comprising a step of expanding the core to seal the sealing portion across the inner peripheral surface of a branch portion of the main pipe portion.

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