Branch pipe connection method

Abstract

To provide a branch pipe connection method that allows for safe and easy connection of branch pipes without damaging the pipeline components by drilling, cutting, or other means. [Solution] A branch pipe connection method for connecting a branch pipe 73 to an existing fluid pipe 2 that constitutes a pipeline in a continuous flow state, comprising at least: a removal jig connection step of sealingly connecting a connection device 200 as a removal jig together with a temporary work valve 216 to a connecting pipe 20a of a branch section 20 integrally formed with the existing fluid pipe 2; a water-stopping member removal step of removing a blocking piece 30 as a water-stopping member built into the connecting pipe 20a through the open temporary work valve 216 using the connection device 200; and a branch pipe connection step of closing the temporary work valve 216, sealingly connecting the branch pipe 73 to the temporary work valve 216 in place of the connection device 200, and opening the temporary work valve 216.

Description

Technical Field

[0001] The present invention relates to a method for connecting a branch pipe to a fluid pipe constituting a pipeline in a non-stop flow state.

Background Art

[0002] Conventional branch pipe connection methods include externally fitting the outer surface of an existing fluid pipe in a sealed manner with a housing, piercing or cutting the pipe wall of the fluid pipe within this housing, and connecting a branch pipe to the branch opening of this housing in a sealed manner (for example, see 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, due to the secular deterioration and rusting of the existing fluid pipe, the structural strength has decreased. Therefore, when forming a branch flow path by piercing or cutting a part of the fluid pipe, there is a problem that the fluid pipe itself may be damaged and there is a risk of fluid leakage.

[0005] The present invention has been made paying attention to such problems, and an object thereof is to provide a branch pipe connection method capable of safely and simply connecting a branch pipe without damaging pipeline components by piercing, cutting, etc.

Means for Solving the Problems

[0006] In order to solve the above problems, the branch pipe connection method of the present invention is a branch pipe connection method for connecting a branch pipe to a fluid pipe constituting a pipeline in a non-stop flow state, wherein The invention is characterized by comprising at least the following steps: a removal jig connection step of sealingly connecting a removal jig together with a work valve to a branch section integrally formed with the fluid pipe; a water-stopping member removal step of removing a water-stopping member built into the branch section through the open work valve using the removal jig; and a branch pipe connection step of closing the work valve, sealingly connecting the branch pipe to the work valve in place of the removal jig, and opening the work valve. According to this feature, by removing the water-stopping member in the branch section, which is integrally formed with the fluid pipe constituting the pipeline, and connecting a branch pipe to this branch section via a work valve, a branch channel can be safely and easily formed without perforating or cutting the pipeline components.

[0007] The water-stopping member is characterized by having a sealing portion that seals the entire circumference of the inner wall of the straight pipe section formed in the branch section, and an operating portion that can expand and contract the sealing portion in the radial direction. This feature ensures high sealing performance by expanding the diameter of the sealing portion of the water-stopping member at the operating portion, while also making it easier to remove the water-stopping member by reducing the diameter of this sealing portion.

[0008] The present invention further comprises a bypass pipe connection step, which involves connecting bypass pipes that bypass both sides of the planned installation location of the fluid pipe to the pipeline, prior to the removal jig connection step, and a fluid pipe connection step, which involves connecting the fluid pipe, in which the water-stopping member is built into the branch section, to the pipeline. According to this feature, by pre-connecting a fluid pipe with a water-sealing member built into the branch section in the preceding fluid pipe connection process, the subsequent branch pipe connection process can be performed at any time.

[0009] The invention is further characterized by including a new pipe connection step, which involves connecting a new fluid pipe having an integrated branch section with a water-stopping member to a pipeline downstream of the fluid pipe, after the branch pipe connection step. According to this feature, by pre-connecting a new fluid pipe with a watertight element built into the branch section to the downstream pipeline after the branch pipe connection process, the branch pipe can be connected to the downstream pipeline at any time.

[0010] The present invention further comprises, after the new pipe connection step, a mounting jig connection step in which the work valve is closed and a mounting jig is sealedly connected to the work valve in place of the branch pipe; a water-stopping member installation step in which a water-stopping member is sealedly attached to the branch portion of the fluid pipe through the open work valve using the mounting jig; and a work valve removal step in which the work valve is removed from the branch portion together with the mounting jig. This feature allows for the sealing of the water-stopping member at the branching point of the fluid pipe, enabling the removal of the work valve along with the branch pipe from the branching point. This eliminates the need to leave any excess material protruding from the pipeline after construction, thus ensuring safety. [Brief explanation of the drawing]

[0011] [Figure 1] This is a plan view showing an existing fluid pipe in which a branch section containing a blockage component is installed, as an embodiment of the present invention. [Figure 2] (a) is a plan view showing the second pipeline section, and (b) is a front view. [Figure 3] This is a cross-sectional view AA of Figure 2(b). [Figure 4] (a) is a diagram showing the pipeline before fluid pipe replacement, (b) is a diagram showing the fluid pipe in the first section of the construction project after replacement, and (c) is a diagram showing the branch pipe removed after the completion of the first section of the construction project. [Figure 5] (d) is a diagram showing the fluid pipes in the second construction section after they have been replaced, and (e) is a diagram showing the branch pipes removed after the second construction section has been completed. [Figure 6] This is a cross-sectional view showing the insertion device body connected to the blocking piece built into the branching section. [Figure 7] This is a cross-sectional view showing the state before a temporary work valve is connected to the blocking piece built into the branch section. [Figure 8] This is a cross-sectional view showing the state in which a temporary work valve is connected to the blocking piece built into the branch section, thereby sealing the inside of the branch section. [Figure 9]It is a cross-sectional view showing a state where an expansion member of a blocking piece is reduced in diameter while a temporary working valve is connected to the blocking piece built in the branch portion. [Figure 10] It is a cross-sectional view showing a state where the blocking piece taken out from the branch portion is retracted into the temporary working valve and the temporary working valve is in a closed state. [Figure 11] It is a cross-sectional view showing a state where the connecting device is removed from the temporary working valve and the branch pipe is connected. [Figure 12] It is a diagram for explaining a modification example of the present invention. (a) is a diagram showing a state where the fluid pipe in the first construction area renewal section of a newly installed fluid pipe branched from an existing fluid pipe is renewed, and (b) is a diagram showing a state where the fluid pipe in the second construction area renewal section of the newly installed fluid pipe is renewed. [Figure 13] It is also a diagram for explaining a modification example of the present invention, and is a diagram showing a state where an existing fluid pipe and a branch pipe connected to the first construction area renewal section are removed.

Mode for Carrying Out the Invention

[0012] A mode for carrying out the branch pipe connection method according to the present invention will be described below based on an example.

Example

[0013] The branch pipe connection method according to the example of the present invention will be described based on FIGS. 1 to 11. In the following description, the front side of FIG. 1 is the front of the fluid pipe, the back side is the rear, the left side is the left, the right side is the right, the left side is the upstream side of the flow path, and the right side is the downstream side of the flow path.

[0014] As shown in Fig. 1, when the structural strength of an existing fluid pipe 2 that constitutes a flow path (pipe line) made of a pipe body decreases due to aging deterioration, rusting, etc., a bypass flow path is configured by connecting a branch pipe to a branch portion formed by perforating or cutting a part of the fluid pipe 2, and construction work is performed to renew the fluid pipe 2 in the section bypassed by this bypass flow path. Such renewal work of the fluid pipe 2 is often carried out sequentially by dividing it into a plurality of work areas in the flow path direction. When the renewal work of the first work area is completed, next, the second work area on the downstream side adjacent to the first work area becomes the renewal target section, and at that time, it is necessary to connect a branch pipe to a predetermined location of the fluid pipe 2 on the downstream side in the first work area where the work has already been completed to configure the bypass flow path of the second work area.

[0015] Therefore, in this embodiment, a first pipe line portion 5 having a shut-off valve 6 and a second pipe line portion 15 in which a branch portion 20 is formed in advance are laid in a part of the fluid pipe 2 to be renewed in the first work area, so that a bypass flow path can be configured using the branch portion 20 provided in the first work area when performing the renewal work of the second work area.

[0016] In addition, the fluid in the fluid pipe 2 is service water in this embodiment, but for example, in addition to industrial water, agricultural water, sewage, etc., it may be a liquid other than water, or it may be a gas or a gas-liquid mixture of gas and liquid. Further, the fluid pipe 2 is a ductile cast iron pipe and is formed into a straight pipe having a substantially circular cross-sectional shape. In this embodiment, the pipe line direction of the fluid pipe 2 is arranged in a substantially horizontal direction. Note that the fluid pipe according to the present invention may be made of other metals such as cast iron and steel, or may be made of concrete, vinyl chloride, polyethylene, polyolefin, etc. Furthermore, the inner peripheral surface of the fluid pipe may be coated with an epoxy resin layer, mortar, plating, etc., or may be coated with an appropriate material on the inner peripheral surface of the fluid pipe by powder coating.

[0017] [Fluid pipe] As shown in Fig. 1, the fluid pipe 2 that constitutes the pipe line has a first pipe line portion 5 having a shut-off valve 6, a second pipe line portion 15 in which a branch portion 20 is formed in advance, and a connection pipe line portion 8 consisting only of a straight pipe having a substantially circular cross-sectional shape. <�

[0018] The first conduit section 5 mainly consists of a pipe body 5a having an insertion section 5b at one end and a receiving section 5c at the other end, and a gate valve 6 having a valve body (not shown) inside that can open and close the conduit within the pipe body 5a.

[0019] As shown in Figures 2(a) and 2(b), the second conduit section 15 mainly consists of a pipe body 15a having an insertion section 15b at one end and a receiving section 15c at the other end, and a connecting pipe 20a that extends forward, branching out from around a branch opening 15d formed at a predetermined location in the axial direction of the pipe body 15a. The connecting pipe 20a constitutes a branch section 20 integrally formed with the pipe body 15a.

[0020] As shown in Figure 3, the connecting pipe 20a has a small diameter section 20b, a medium diameter section 20c, and a large diameter section 20d, forming a receiving section in which the diameter gradually increases from the pipe body 15a side toward the front. A sealing element 30 is provided in the small diameter section 20b as a water-stopping member to stop water from flowing through the branch opening 15d, and is fixed by pressing rings 95 provided in the medium diameter section 20c and the large diameter section 20d, preventing it from deviating from the small diameter section 20b. The small diameter section 20b is formed as a straight pipe section with approximately the same diameter in the branching direction.

[0021] The closure piece 30 includes a disc-shaped tip member 45 with a diameter smaller than the inner diameter of the small-diameter portion 20b, a disc-shaped base member 47 with approximately the same diameter as the tip member 45, an expansion member 48 made of rubber material with approximately the same diameter as the tip member 45 and the base member 47, and a crimping bolt 50 for pressing the expansion member 48 against the inner wall surface of the small-diameter portion 20b. A screw hole 56 for connecting to the insertion machine head 240, which will be described later, is formed axially on the front end surface of the base member 47.

[0022] The extension member 48 is held between the tip member 45 and the base member 47 such that its rear end is fitted into the groove of the tip member 45 and its front end is fitted into the groove of the base member 47.

[0023] The crimping bolt 50 has a restricting portion 51 formed at its rear end that allows rotation of the tip member 45 around its axis while restricting axial movement. A rod-shaped portion 50a is formed in front of the restricting portion 51 and is loosely fitted into the insertion hole 52 of the tip member 45. A male threaded portion 50b is formed in front of the rod-shaped portion 50a. The front end of the male threaded portion 50b protrudes forward from the front end opening of the insertion hole 53, and a nut 115 is screwed onto the protruding male threaded portion 50b via a washer 114. Furthermore, relative rotation of the tip member 45 and the base member 47 around the crimping bolt 50 is restricted.

[0024] When the crimping bolt 50 is rotated while the base end member 47 of the closing piece 30 is fixed in a non-rotatable state, the crimping bolt 50 moves forward relative to the base end member 47. As a result of this movement, the tip member 45, which is restricted by the restricting part 51, is pressed toward the base end member 47, and the distance between the tip member 45 and the base end member 47 is shortened. As a result, the expansion member 48 is compressed between the tip member 45 and the base end member 47, and the outer circumferential wall of the expansion member 48 expands in diameter while deforming in the outward direction, and is pressed against the inner wall surface of the small diameter portion 20b. In other words, the closing piece 30 can be transformed between an un-closing state (not shown) that does not close the inside of the communication pipe 20a and a closed state (see Figure 3) that seals the inside of the communication pipe 20a.

[0025] As shown in Figure 3, the pressing ring 95 mainly consists of a cylindrical contact member 102 that can abut against the rear end surface of the base end member 47 of the closing piece 30, and a flange 94 formed to protrude radially outward from the rear end of the contact member 102. An annular joint rubber ring 161 made of an elastic material is fitted onto the outer circumferential surface of the contact member 102. In addition, a plurality of bolt fixing holes 96 arranged in the circumferential direction are provided on the rear surface of the pressing ring 95.

[0026] With the rear end surface of the contact member 102 in contact with the front end surface of the base end member 47 of the closing piece 30, the flange 20f of the connecting pipe 20a and the flange 94 of the pressing ring 95 are fastened together with bolts and nuts 160, thereby fixing the pressing ring 95 to the branch section 20, and the closing piece 30 is supported by the pressing ring 95 from the downstream side.

[0027] Furthermore, a portion of the closing cover 97 is fitted into the central through-hole 102a of the contact member 102 by a bolt 98 attached to a bolt fixing hole 96. In addition, a bolt 99 is attached to the center of the closing cover 97 and is screwed into a threaded hole 116 formed at the front end of the crimping bolt 50, thereby connecting and fixing the closing cover 97 and the crimping bolt 50. By connecting and fixing the closing cover 97 and the crimping bolt 50, the closing piece 30 is prevented from shrinking in diameter, thus avoiding a decrease in sealing performance, and making it possible to maintain the branch section 20 in a closed state for a long period of time.

[0028] Furthermore, since the rubber ring 161 for the joint is fitted to the pressing ring 95, water leakage from between the inner surface of the connecting pipe 20a and the outer surface of the pressing ring 95 is prevented, and since the packing 162 is fitted to the closing cover 97, water leakage from between the inner surface of the pressing ring 95 and the outer surface of the closing cover 97 is prevented, so that the inside of the connecting pipe 20a is sealed.

[0029] [How to replace fluid pipes] Next, a method for replacing the existing fluid pipe 2 in a continuous flow state will be explained based on Figures 4 and 5.

[0030] As shown in Figure 4(a), the existing fluid pipe 2 has multiple first pipeline sections 5 with gate valves 6 that can open and close the flow path installed in the axial direction of the pipe (only one is shown in Figure 4), and each first pipeline section 5 is connected to a connecting pipeline section 8. Below, a method for updating the first section of the fluid pipe 2 downstream of a predetermined first pipeline section 5 in a continuous flow state will be described. In the following description, "section to be updated" means the section before the update work, and "updated section" means the section during or after the update work.

[0031] As shown in Figure 4(b), in the continuous flow branching method, a split T-pipe 62 and a work valve 62a are installed upstream of the gate valve 6, and a split T-pipe 64 and a work valve 64a are installed downstream of the first construction section renovation area, and the pipe body 5a and connecting pipeline section 8 are drilled. Furthermore, a continuous flow stop valve 65 is installed upstream of the split T-pipe 64, and both split T-pipes 62 and 64 are connected by a branch pipe 63. Next, with the branch pipe 63 open, the gate valve 6 and the continuous flow stop valve 65 are closed to create a bypass flow path that bypasses both split T-pipes 62 and 64 by the branch pipe 63 (bypass pipe connection process). In this state, the existing connecting pipeline section of the first construction section to be renovated is removed, and a new first pipeline section 5 with a gate valve 6 and a new second pipeline section 15 with a branch section 20 are laid downstream of the new connecting pipeline section 8 within the first construction section to be renovated (fluid pipe connection process). A blockage block 30 is pre-installed in this branch section 20.

[0032] Next, as shown in Figure 4(c), once the construction of the first section of the pipeline is completed, the work valve 62a connected to the split T-joint 62 installed on the pipe body 5a of the existing first pipeline section 5, and the work valve 64a connected to the split T-joint 64 installed on the existing connecting pipeline section 8 are closed, and the branch pipe 63 is removed. The split T-joints 62, 64 and the work valves 62a, 64a are left in place to close the branch holes drilled for the bypass.

[0033] After the construction of the first section of the renovation is completed, as shown in Figure 5(d), when the fluid pipe 2 of the second section of the renovation, which is adjacent to the downstream side of the first section of the renovation, is to be renovated, the construction of the second section of the renovation will be carried out in the same way as the construction of the first section of the renovation, using the continuous flow branching method to connect the upstream and downstream sides of the second section of the renovation with a branch pipe 73 to form a bypass flow path, but the upstream end of the branch pipe 73 will be connected to the branch section 20 that was renovated in the construction of the first section of the renovation.

[0034] In detail, a split T-joint pipe 72 and a work valve 72a are installed in the existing connecting pipeline section 8 downstream of the section to be renovated in the second construction section, and a hole is drilled in the existing connecting pipeline section 8. Furthermore, a continuous flow stop valve 75 is installed upstream of the split T-joint pipe 72. Meanwhile, a connecting device 200 (see Figures 6 to 10), which will be described later, is connected to the branch section 20 of the newly constructed second pipeline section 15 installed in the first construction section to be renovated (removal jig connection process, see Figure 6). The attached pressing ring 95 and blocking piece 30 are removed, and a temporary work valve 216 is installed (water-stopping member removal process, see Figures 6 to 8). Then, the branch pipe 73 connected to the work valve 72a of the split T-joint pipe 72 is connected to the temporary work valve 216 connected to the branch section 20 of the newly constructed second pipeline section 15. Next, with the branch pipe 73 open, the gate valve 6 and the continuous flow stopper plug 75 are closed to form a bypass flow path with the branch pipe 73 (branch pipe connection process, see Figures 9 to 11). In this state, the existing connecting pipeline section 8 in the section to be renovated in the second construction area is removed, and a new first pipeline section 5 with a gate valve 6 and a new second pipeline section 15 with a branch section 20 are laid downstream of the new connecting pipeline section 8 within the section to be renovated in the second construction area, completing the renovation (new pipe connection process, see Figure 5(d)). Details of the branch pipe connection method, namely the removal jig connection process, the water-stopping member removal process, the branch pipe connection process, and the new pipe connection process, are explained in detail in Figures 6 to 11.

[0035] Once the renovation work for Section 2 is completed, as shown in Figure 5(e), after the new pipe connection process, the temporary work valve 216 is closed, and a connecting device 200, which serves as an installation jig, is sealedly connected to the temporary work valve 216 in place of the branch pipe 73 (installation jig connection process). The connecting device 200 is then used to seally attach the blocking piece 30 to the connecting pipe 20a of the newly installed Section 2 pipeline 15 through the open temporary work valve 216 (water-stopping member installation process). The temporary work valve 216 is then removed from the connecting pipe 20a along with the connecting device 200, and the work is completed (work valve removal process). Thereafter, by repeating this process, the existing fluid pipe 2 can be renewed in a state of continuous flow.

[0036] [Method for connecting branch pipes] Next, as explained in Figure 5(d), the method of removing the blocking piece 30 from inside the branch section 20 of the newly installed second pipeline section 15 installed in the first section renovation area, and connecting the branch pipe 73 to the branch section 20, will be explained based on Figures 3, 6 to 11. Note that the removal of the blocking piece 30 and the connection of the branch pipe 73 to the branch section 20 will be carried out under continuous flow conditions. The branch pipe connection method consists of at least the removal jig connection process, the water-stopping member removal process, and the branch pipe connection process, as will be described later. In addition, the solid arrows shown in Figures 6 to 11 indicate the direction of movement of the members in the branch pipe connection method, and the dotted arrows indicate the direction of movement of the members in the branch pipe removal method, which will be described later.

[0037] [Removal jig connection process] First, the closing cover 97 is removed from the pressing ring 95 attached to the connecting pipe 20a of the branch section 20 shown in Figure 3. Next, as shown in Figure 6, the rear end of the insertion device body 258 is inserted into the through hole 102a of the pressing ring 95 and connected to the closing piece 30 via a connecting socket 250, which will be described later. The insertion device body 258 mainly consists of an outer shaft member 254 made of a hollow, elongated metal tube and a cylindrical inner shaft member 265 which is rotatably fitted inside the outer shaft member 254 and is slightly longer than the outer shaft member 254. A connecting socket 250 with a hexagonal hole formed inside is welded to the rear end of the inner shaft member 265 of the insertion device body 258, and by fitting the connecting socket 250 onto the nut 115 of the closing piece 30, the inner shaft member 265 and the crimping bolt 50 are connected so that they cannot rotate relative to each other. This makes it possible to expand and contract the diameter of the expansion member 48 while deforming it by rotating the central shaft member 265 around its axis.

[0038] Furthermore, a split support member 264 fitted onto the outer circumference of the connecting pipe 20a and a movable plate 261 that supports the rear end of the insertion device body 258 connected to the blocking piece 30 are connected by a rod-shaped support column 263 that extends along the pipe axis of the connecting pipe 20a. The insertion device body 258 is then supported at the branching section 20 by the movable plate 261, the support column 263, and the support member 264, thereby fixing the blocking piece 30 inside the connecting pipe 20a.

[0039] Next, the pressing ring 95 is removed from the flange 20f of the connecting pipe 20a and moved along the insertion device body 258 in the direction indicated by the solid arrow in Figure 6. The two-part temporary pressing ring 292 is then inserted into the connecting pipe 20a and brought into contact with the closing piece 30. The closing piece 30 is then temporarily fixed inside the connecting pipe 20a by attaching it to the flange 20f of the connecting pipe 20a with a bolt and nut 251. After temporarily fixing the closing piece 30 with the temporary pressing ring 292, the pressing ring 95 is moved along the insertion device body 258, the moving plate 261 is removed (not shown), and the pressing ring 95 is removed from the insertion device body 258.

[0040] [Water-stopping component removal process] Next, as shown in Figure 7, the temporary work valve 216, the short pipe 231 having an insertion port 231a that can be inserted into the connecting pipe 20a, the thrust ring 10 and packing 12 deposited in the insertion port 231a, and the short pipe 232 with its rear end closed are inserted into the insertion device body 258. The temporary work valve 216 mainly consists of a valve body 217, a valve cover 218 sealed to the valve body 217, and a valve element 219 that is provided to move back and forth within the valve body 217 from the valve cover 218. Flanges 217f, 217f are provided protruding outward from the openings on both sides of the valve body 217 in the direction of the pipe axis, and are sealed to the flange 231f of the short pipe 231 and the flange 232f of the short pipe 232, respectively. After inserting the temporary work valve 216 and the short pipes 231 and 232 connected to the temporary work valve 216 from the front end of the insertion device body 258, the movable plate 261 is attached to the insertion device body 258, the support 264 and the movable plate 261 are connected by the support column 263, and the occlusion piece 30 is fixed inside the connecting pipe 20a. Next, after removing the temporary thrust ring 292 from the flange 20f of the connecting pipe 20a, the two-part insertion machine head 240 attached to the rear end of the insertion device body 258 is connected to the occlusion piece 30.

[0041] Next, as shown in Figure 8, the rear end of the feed screw member 262 is fixed to the flange 232f of the short pipe 232, and the front end of the feed screw member 262 is inserted into the movable plate 261 and the nut 262a is screwed on, thereby supporting the feed screw member 262 with the movable plate 261. Then, the nut 262a is loosened, and the temporary work valve 216 and the short pipes 231 and 232 are moved relative to the insertion device body 258 toward the branch section 20 in the direction indicated by the solid arrow in Figure 8, and the suction opening 231a of the short pipe 231 is inserted into the connecting pipe 20a. After that, the packing 12 is inserted between the connecting pipe 20a and the suction opening 231a of the short pipe 231, and the thrust ring 10 is fastened to the connecting pipe 20a with a bolt and nut 11. This causes the packing 12 to be pressed toward the pipe body 15a, and restricts the detachment of the short pipe 231 from inside the connecting pipe 20a.

[0042] [Branch pipe connection process] Next, as shown in Figure 9, the central shaft member 265 of the insertion device body 258 is loosened, and the expansion member 48 of the blocking piece 30 is deformed to an open state. At the same time, the air venting bolt (not shown) provided inside the valve cover 218 of the temporary work valve 216, or the bolt (not shown) that secures the packing box (not shown) on top of the valve cover 218 is loosened to vent the air. As a result, the fluid in the pipe body 15a (fluid pipe 2) fills the connecting pipe 20a, the temporary work valve 216, and the short pipes 231 and 232.

[0043] Once the connecting pipe 20a, the temporary work valve 216, and the short pipes 231 and 232 are filled with fluid, loosen the nuts 262a, 262a as shown in Figure 10, and move the insertion device body 258 together with the movable plate 261 in the forward direction indicated by the solid arrow in Figure 10. Then, once the blocking piece 30 has moved to the short pipe 232 side of the valve body 219, move the valve body 219 towards the valve casing 217 to close the inside of the valve casing 217.

[0044] Next, as shown in Figure 11, the other support members 264, support column 263, movable plate 261, short pipe 232, insertion device body 258, and blocking piece 30 are removed from the branch section 20, leaving the short pipe 231 and temporary work valve 216 in place. Then, the branch pipe 73 is sealed and connected to the temporary work valve 216 as shown by the solid arrow in Figure 11, and the temporary work valve 216 is opened, completing the connection work of the branch pipe 73 to the connecting pipe 20a of the branch section 20.

[0045] [How to remove branch pipes] Furthermore, as shown in Figures 5(d) and (e), after the completion of the second section renovation work, that is, after the newly constructed first pipeline section 5 and second pipeline section 15 have been laid, the branch pipe 73 is opened and closed, and the bypass flow path of the branch pipe 73 is removed. Details of the branch pipe removal method, that is, the installation jig connection process, the water-stopping member installation process, and the work valve removal process, are the reverse of the connection method described in Figures 6 to 11.

[0046] To briefly explain the method for removing the branch pipe, as shown in Figure 11, the temporary work valve 216 connected to the connecting pipe 20a integrally formed with the pipe body 15a, which is the fluid pipe 2, is closed, and the branch pipe 73 is removed as indicated by the dotted arrow in Figure 11. Next, as shown in Figure 10, the support member 264, support column 263, movable plate 261, short pipe 232, insertion device body 258, and closing piece 30, which are the connecting device 200, are connected in a sealed manner in place of the branch pipe 73 connected to the temporary work valve 216 (mounting jig connection process).

[0047] Next, the valve body 219 is raised to open the temporary work valve 216, and the insertion device body 258 and the blocking piece 30 are moved toward the connecting pipe 20a side indicated by the dotted arrow. Then, as shown in Figure 9, after confirming that the blocking piece 30 has reached the small diameter section 20b of the connecting pipe 20a, the front end of the central shaft member 265 of the insertion device body 258 is rotated to expand the diameter of the expansion member 48 of the blocking piece 30 connected to the central shaft member 265, thereby sealing the small diameter section 20b and stopping water from entering the connecting pipe 20a (water-stopping member installation process). Furthermore, the thrust ring 10 and packing 12 are removed from the connecting pipe 20a, the nut 262a of the feed screw member 262 is loosened, and as shown in Figure 7, the temporary work valve 216 and short pipes 231 and 232 are moved towards the movable plate 261 indicated by the dotted arrow, the two-part insertion machine head 240 is removed from the insertion device body 258, the temporary thrust ring 292 is attached to the connecting pipe 20a, and then the temporary work valve 216 and short pipes 231 and 232 are removed (work valve removal process).

[0048] After temporarily fixing the blocking piece 30 with the temporary thrust ring 292, as shown in Figure 6, the pressing thrust ring 95 is inserted from the front end of the insertion device body 258. Finally, with the insertion device body 258 supported at the branch section 20 by the movable plate 261, support column 263 and support member 264, the temporary thrust ring 292 is removed and the pressing thrust ring 95 is attached to the connecting pipe 20a to fix the blocking piece 30. Then, the support of the insertion device body 258 at the branch section 20 is released, and the connection device 200 is dismantled to complete the process.

[0049] In this embodiment, the connecting device 200, which serves as a removal and installation jig for the blocking piece 30, includes a support 264, a support column 263, a movable plate 261, short pipes 231 and 232, an insertion device body 258, a temporary thrust ring 292, a thrust ring 10, etc. However, it does not necessarily have to include all of these components, and it may also include other components.

[0050] [Effects / Effects] As described above, the branch pipe connection method as an embodiment of the present invention is a branch pipe connection method for connecting a branch pipe 73 to an existing fluid pipe 2 constituting a pipeline in a state of continuous flow, and comprises at least a removal jig connection step (see Figures 5(d) and 6) in which a connection device 200 as a removal jig is sealed together with a temporary work valve 216 to a connecting pipe 20a of a branch section 20 integrally formed with the existing fluid pipe 2, a water-stopping member removal step (see Figures 5(d), 6 to 8) in which a blocking piece 30 as a water-stopping member built into the connecting pipe 20a is removed by the connection device 200 through the open temporary work valve 216, and a branch pipe connection step (see Figures 5(d), 9 to 11) in which the temporary work valve 216 is closed, the branch pipe 73 is sealed together with the temporary work valve 216 in place of the connection device 200, and the temporary work valve 216 is opened.

[0051] According to this, by removing the blocking piece 30 inside the branch section 20 which is integrally formed with the pipe body 15a of the second pipeline section 15 in the newly constructed fluid pipe 2 that constitutes the pipeline, and connecting the branch pipe 73 to this connecting pipe 20a via a temporary work valve 216, a bypass flow path (branch flow path) can be safely and easily formed without drilling or cutting the pipeline components such as the second pipeline section 15.

[0052] Furthermore, the second conduit section 15 is integrally formed with the pipe body 15a and the connecting pipe 20a which serves as the branch section 20. The connecting pipe 20a has a receiving section into which the suction part of the branch pipe can be inserted, making it easy to insert and remove the suction parts of the closure piece 30 and the branch pipe short pipe 231. In addition, the closure piece 30 is fixed to the small diameter section 20b close to the pipe body 15a, and the short pipe 231 and the pressing ring 95 are inserted into the medium diameter section 20c and the large diameter section 20d. The stepped section between the small diameter section 20b and the medium diameter section 20c prevents the closure piece 30 from falling into the pipe body 15a due to overinsertion of the short pipe 231 or the pressing ring 95, thus making it easy to connect and disconnect the branch pipe.

[0053] Furthermore, since the connecting pipe 20a is configured as a receiving section with an opening at its front end and no holes or other openings formed in its circumferential wall, a temporary work valve 216 or the like can be connected to the opening. Therefore, when the branch pipe is removed, the temporary work valve 216 can be removed together with the branch pipe, thus ensuring safety by not leaving any excess components protruding from the pipeline after construction, as is the case with the temporary work valve 216. Moreover, since a highly versatile branch section can be used that allows for the connection of a temporary work valve 216 or the like to the opening, manufacturing costs can be reduced.

[0054] Furthermore, the sealing piece 30 has an expansion member 48 as a sealing part that seals the entire circumference of the inner wall of the small-diameter section 20b, which is a straight pipe section formed in the connecting pipe 20a, and a central shaft member 265 and a crimping bolt 50 as an operating part that can expand and contract the expansion member 48 in the radial direction. By expanding the diameter of the expansion member 48 of the sealing piece 30 with the tip member 45, high sealing performance is ensured, and by contracting the diameter of the expansion member 48, the sealing piece 30 can be easily removed.

[0055] Furthermore, by including a bypass pipe connection process (see Figure 4(b)) in which a branch pipe 63, which serves as a bypass pipe that bypasses both sides of the first construction section renovation area where the fluid pipe 2 is planned to be installed, is connected to the pipeline before the removal jig connection process (see Figures 5(d) and 6), and a fluid pipe connection process (see Figure 4(b)) in which a newly constructed second pipeline section 15, in which a blocking piece 30 is built into the connecting pipe 20a, is connected to the pipeline in advance during the preceding fluid pipe connection process, the subsequent branch pipe connection process can be performed at any time.

[0056] Furthermore, by adding a new pipe connection step (see Figure 5(d)) after the branch pipe connection step (see Figures 5(d), 9 to 11), in which a newly constructed second pipe section 15, which has a connecting pipe 20a with a built-in blocking element 30 integrated into it, is connected to the pipeline downstream of the existing fluid pipe 2, the branch pipe can be connected to the pipeline further downstream at any time by pre-connecting the new second pipe section 15 with the connecting pipe 20a and the built-in blocking element 30 to the pipeline downstream after the branch pipe connection step.

[0057] Furthermore, the system includes, after the new pipe connection process (see Figure 5(d)), a mounting jig connection process (see Figures 11 and 10) in which the temporary work valve 216 is closed and the connecting device 200 as an attachment jig is sealed to the temporary work valve 216 in place of the branch pipe 73; a water-stopping member installation process (see Figures 9 and 8) in which the blocking piece 30 is sealed to the connecting pipe 20a through the open temporary work valve 216 using the connecting device 200; and a work valve removal process (see Figure 7) in which the temporary work valve 216 is removed from the connecting pipe 20a together with the connecting device 200. With this system, by sealing the blocking piece 30 to the connecting pipe 20a, the temporary work valve 216 can be removed from the connecting pipe 20a together with the branch pipe 73, so that no excess material protruding from the pipeline after construction is left behind, and safety can be ensured.

[0058] Furthermore, the branch pipe removal method of the present invention, which is the reverse process of the branch pipe removal method described in Figures 6 to 11, is as follows: A method for removing a branch pipe (branch pipe 73) from a fluid pipe (fluid pipe 2) constituting a pipeline while maintaining a continuous flow, preferably comprising at least the following steps: a mounting jig connection step (see Figures 11 and 10) in which a work valve (temporary work valve 216) connected to a branch section integrally formed with the fluid pipe is closed, and a mounting jig (connecting device 200) is connected in a sealed manner in place of the branch pipe connected to the work valve; a water-stopping member installation step (see Figures 9 and 8) in which a water-stopping member (blocking piece 30) is installed in a sealed manner on the branch section through the open work valve using the mounting jig; and a work valve removal step (see Figure 7) in which the work valve is removed from the branch section together with the mounting jig.

[0059] According to this method, no excess material protruding from the pipeline after construction using branch pipes is left behind, thus ensuring safety.

[0060] Although embodiments of the present invention have been described above with reference to the drawings, the specific configurations are not limited to these embodiments, and any changes or additions that do not depart from the spirit of the present invention are also included.

[0061] [Differentiation] Next, modifications of the present invention will be described with reference to Figures 12 and 13. In the above embodiment, an example was given in which the pipe body in any renewal section is renewed with a newly constructed first pipe section 5 and a newly constructed second pipe section 15 having a branch section 20 without changing the occupied position of the pipeline consisting of the existing fluid pipe 2. However, as shown in Figure 12(a), when extending the pipeline by changing the occupied position of the pipeline consisting of the existing fluid pipe 2A to a pipeline consisting of a newly constructed fluid pipe 2B that branches forward from the existing fluid pipe 2A, the pipeline may be renewed (laid) with a newly constructed first pipe section 5 and a newly constructed second pipe section 15 having a branch section 20 for each predetermined work section renewal section.

[0062] To explain in more detail, as shown in Figure 12(a), in the continuous flow branching method, a split T-joint 62 and a work valve 62a are installed at a predetermined location on the existing fluid pipe 2A, and a split T-joint 64 and a work valve 64a are installed downstream thereof, and continuous flow stop valves 65 and 65 are installed between the split T-joints 62 and 64. Next, a new gate valve 6 is installed at a predetermined location on the new fluid pipe 2B connected to the split T-joint 62, and a new connecting pipeline section 8, a new first pipeline section 5 with a new gate valve 6, and a new second pipeline section 15 with a branch section 20 are installed in the first construction section renewal area downstream thereof.

[0063] Furthermore, the blocking piece 30 (not shown) built into the branch section 20 installed in the first construction section renovation area is removed in an uninterrupted flow state using the removal jig described in the above embodiment, and after installing the short pipe 231 and the temporary work valve 216, the temporary work valve 216 and the split T-pipe 64 installed in the existing fluid pipe 2A are connected by the branch pipe 74. In this way, the first bypass road 83, which has a roughly U-shape in plan view, is formed by the branch pipe consisting of the newly installed fluid pipe 2B, the newly installed gate valve 6, the newly installed connecting pipeline section 8, the newly installed second pipeline section 15, the short pipe 231, the temporary work valve 216, and the branch pipe 74.

[0064] Next, as shown in Figure 12(b), a new connecting pipeline section 8, a new first pipeline section 5 with a new gate valve 6, and a new second pipeline section 15 with a branch section 20 are installed in the second construction section update section downstream of the new first pipeline section 5 in the pipeline consisting of the newly installed fluid pipe 2B. Furthermore, the blocking piece 30 (not shown) built into the branch section 20 installed in the second construction section update section is removed in an uninterrupted flow state using the removal jig described in the above embodiment, and after installing the short pipe 231 and the temporary work valve 216, the temporary work valve 216 and the split T-pipe 64 installed in the existing fluid pipe 2A are connected by the branch pipe 74. In this way, a second bypass road 84 is formed, which in plan view is roughly U-shaped, by the newly installed fluid pipe 2B, the newly installed gate valve 6 in the first construction section renovation area, the newly installed connecting pipeline section 8, the newly installed second pipeline section 15 and the newly installed first pipeline section 5, and the newly installed connecting pipeline section 8 in the second construction section renovation area, the newly installed second pipeline section 15, the short pipe 231, the temporary work valve 216 and the branch pipe 74.

[0065] Once the second bypass 84 is formed, as shown in Figure 13, the pipe section of the existing fluid pipe 2A that has been bypassed by the second bypass 84, the short pipe 231, the temporary work valve 216, and the branch pipe 74 can be removed using the method described in the [Method for Removing the Branch Pipe] section of the above embodiment.

[0066] [Other variations] Furthermore, while the above embodiment illustrates a method of connecting one end of a branch pipe 73 laid when updating the pipe body in the second work section update area to a branch section 20 of a newly constructed second pipeline section 15 in the upstream work section update area, the present invention is not limited to this, and may also be connected to a branch section 20 of a newly constructed second pipeline section 15 in the downstream work section update area. In addition, the method of connecting one end of a branch pipe (bypass pipe) laid when updating the pipe body in a predetermined work section update area of ​​an existing fluid pipe 2 to a newly constructed branch section in another work section update area is not limited to this, but may also be a method of connecting a branch pipe to a branch section 20 of a newly constructed second pipeline section 15 in another fluid pipe 2B that branches off from the existing fluid pipe 2, as described in the above modified example. In other words, the branch section may be pre-installed not only in the existing fluid pipe 2 but also in the newly constructed fluid pipe, as long as it is a fluid pipe that constitutes the pipeline.

[0067] Furthermore, in the above embodiment, the branch pipe connected to the branch section was exemplified as a bypass pipe that constitutes a bypass flow path for bypassing a predetermined work section renovation area. However, the present invention is not limited to this, and branch pipes other than bypass pipes may also be used, such as connecting pipes for connecting a predetermined fluid pipe to other fluid pipes.

[0068] Furthermore, in the above embodiment, the connecting pipe 20a constituting the branch section 20 is exemplified as having a receiving portion into which the spigot portion of the branch pipe can be inserted. However, the present invention is not limited to this, and may have a spigot portion into which the receiving portion of the branch pipe can be inserted. Also, the shape and other aspects are arbitrary, and it is not necessarily required that a small diameter section 20b, a medium diameter section 20c, a large diameter section 20d, etc., be formed.

[0069] Furthermore, although the above embodiment illustrates a configuration in which a blocking piece 30 is applied as an example of a water-stopping member, the present invention is not limited thereto, and other water-stopping members other than the blocking piece 30 (for example, plugs or valve bodies) may be applied as long as they can stop water from entering the connecting pipe 20a.

[0070] Furthermore, in the above embodiment, a temporary work valve 216 connected to the branch section 20 together with the branch pipe 73 was shown to be removed together with the branch pipe 73 after a second pipeline section 15 having a branch section 20 was newly constructed in the downstream work section renewal area. However, the present invention is not limited to this, and it is not necessarily required to remove the temporary work valve 216. [Explanation of Symbols]

[0071] 2.2A Fluid pipe (existing fluid pipe) 2B Fluid pipe (newly installed fluid pipe) 5 1st pipe section 6. Gate valve 8. Connecting conduit section 15 Second pipe section 15a Body 15b Socket 15c Socket part 15d Branch Outlet 20 Branching point 20a Connecting pipe (branch section) 20b Small diameter section (straight pipe section) 20c medium diameter part 20d Large diameter section 30. Blocking piece (water-stopping component) 45 Tip member 47 Base end member 48. Expansion member (seal part) 50 Crimping bolt (operating part) 73, 74 Branch pipe (bypass pipe) 83 First Bypass Road 84 Second Bypass Road 95 Pressing Ring 200 Connection devices (removal jigs, mounting jigs) 216 Work valve (temporary work valve) 219 Valve body 231,232 Short pipe 240 Insertion machine head 250 Linking Sockets 254 Outer shaft member 258 Insertion device body 261 Mobile Plate 262 Lead screw component 263 Post 264 Supports 265 Central shaft component (operating part) 292 Temporary retaining ring

Claims

1. A method for connecting branch pipes to fluid pipes constituting a pipeline in a state of continuous flow, A branch pipe connection method characterized by comprising at least the following steps: a removal jig connection step of sealingly connecting a removal jig together with a work valve to a branch section integrally formed with the fluid pipe; a water-stopping member removal step of removing a water-stopping member built into the branch section through the open work valve using the removal jig; and a branch pipe connection step of closing the work valve, sealingly connecting the branch pipe to the work valve in place of the removal jig, and opening the work valve.

2. The branch pipe connection method according to claim 1, characterized in that the water-stopping member has a sealing portion that seals the entire circumference of the inner wall of the straight pipe portion formed in the branch portion, and an operating portion that can expand and contract the sealing portion in the radial direction.

3. The branch pipe connection method according to claim 1, further comprising: a bypass pipe connection step of connecting bypass pipes that bypass both sides of the planned installation location of the fluid pipe to the pipeline, prior to the removal jig connection step; and a fluid pipe connection step of connecting the fluid pipe, in which the water-stopping member is built into the branch section, to the pipeline.

4. The branch pipe connection method according to claim 1, further comprising a new pipe connection step, which involves connecting a new fluid pipe having an integrated branch section with a water-stopping member to a pipeline downstream of the fluid pipe, after the branch pipe connection step.

5. The branch pipe connection method according to any one of claims 1 to 4, further comprising: a mounting jig connection step, which involves closing the work valve and sealing the mounting jig to the work valve in place of the branch pipe, after the new pipe connection step; a water-stopping member installation step, which involves sealing the water-stopping member to the branch portion of the fluid pipe through the open work valve using the mounting jig; and a work valve removal step, which involves removing the work valve together with the mounting jig from the branch portion.

Images