JP7791302B2 - Switching valve device and pipe laying method using the device - Google Patents

Description

The present invention relates to a switching valve device used when removing or replacing an existing flow path without interrupting flow and laying a new flow path, and a pipe laying method using the device.

When working to replace an existing water supply pipeline, for example, it is desirable to maintain an uninterrupted flow, i.e., a continuous water flow, for the convenience of water users. A conventional method for creating a flow path without interrupting the flow involves sealingly fitting a housing with a split structure onto the existing fluid pipe, cutting the existing fluid pipe inside the housing, inserting a switching valve with a valve box and valve element into the cut section of the pipe inside the housing, and connecting a new pipe alongside the existing fluid pipe. The valve element is then operated to open and close a port in the valve box, thereby switching the flow path from the existing fluid pipe to the new pipe.

Water treatment facilities such as water purification plants and distribution plants that treat drinking water are equipped with multiple water tanks, pump rooms, valve chests, water towers, etc., and the pipes connecting these and those distributing water downstream are laid in close proximity to one another. In recent years, at water treatment facilities with such a large number of pipes, multiple pipes have reached the end of their useful life at once, requiring replacement, or pipes needing to be strengthened, for example, by making them earthquake-resistant, or pipes needing to be duplicated in preparation for disasters. In particular, at water treatment facilities that handle domestic water, it is essential to replace existing pipes with new pipes or lay new pipes without interrupting the flow of water.

One example of a switching valve device used in this type of flow path formation method under uninterrupted flow conditions is a valve box with three openable ports housed within a housing with three openings. Two of the openings are connected to existing pipes that have been separated within the housing, while the remaining opening can be connected to a new pipe. After the housing is fitted over the existing pipe and the new pipe is connected, the valve element inside the valve box closes the port that connects to the existing pipe downstream, allowing fluid to flow from the existing pipe upstream to the new pipe. This allows the existing pipe downstream with its port blocked to be removed or replaced under uninterrupted flow conditions. (See Patent Document 1)

JP 2011-75052 A (page 1, Figure 1)

However, with the switching valve device of Patent Document 1, only one new pipe can be connected in addition to the existing pipe fitted to the housing. Therefore, if the switching valve device of Patent Document 1 is used to replace or add new pipes to an existing flow path consisting of multiple existing pipes, multiple switching valve devices must be installed, making it less scalable. This makes pipe installation work more complicated and leads to increased costs. Furthermore, in this case, a large construction space is required, making construction impossible in some cases.

The present invention was developed to address these problems, and aims to provide a highly scalable switching valve device and a pipe installation method using the device, even when multiple existing pipes need to be replaced with new pipes or new pipes need to be added in situations where a large number of existing pipes are installed.

In order to solve the above problems, the switching valve device of the present invention comprises:
A switching valve device that can connect a new fluid pipe to the housing in an uninterrupted flow state, the switching valve comprising a housing with a split structure that has an opening for connecting a fluid pipe and that fits tightly onto an existing fluid pipe, and a switching valve that is installed tightly at a cut portion of the existing fluid pipe within the housing, the switching valve being configured to connect a new fluid pipe to the housing in an uninterrupted flow state,
The openings are formed in the housing in a generally cross-shaped manner,
The switching valve is characterized by comprising a valve body in which ports communicating with the openings are formed in a substantially cross-shaped manner, and a valve body capable of selectively closing one of the ports.
According to this feature, by blocking one of the ports formed in an approximately cross-shaped manner with a valve body, an uninterrupted flow state can be maintained through the remaining three ports that are open, while the existing fluid pipe connected to the opening side that communicates with the port whose valve body is blocked can be removed and a new fluid pipe can be laid in sequence, making it possible to update multiple fluid pipes and providing high construction scalability.

The switching valve is characterized in that a restricting member is provided to restrict the valve body from closing a specific one of the ports.
According to this feature, the restricting member can keep a specific port open at all times, thereby always maintaining an uninterrupted flow state in the fluid pipe connected to the opening communicating with this port, and preventing a state of flow interruption due to accidental blockage.

The valve element is rotatable around a rotation axis provided in the center of the switching valve, and the rotation angle of the valve element is restricted to within 270 degrees by the restricting member, thereby blocking ports except for the specific port.
According to this feature, since the valve element is restricted by the restricting member from passing through the specific port, it is possible to prevent a temporary flow interruption that occurs when the valve element passes through.

The opening angle formed by the sealing members sealing a pair of ports facing each other among the ports formed in the approximately cross direction is smaller than the opening angle formed by the sealing members sealing the remaining pair of ports approximately perpendicular to the first pair of ports.
According to this feature, it is possible to minimize the influence of the fluid in the fluid pipe connected to the opening communicating with the port on the side with the smaller opening angle.

A pipe laying method for laying a new fluid pipe in an uninterrupted flow state using the switching valve device according to any one of claims 1 to 4, comprising:
The method includes the steps of: sealingly fitting the housing onto an existing fluid pipe; cutting a portion of the existing fluid pipe inside the housing while closing an opening of the housing for connecting a new fluid pipe; installing the switching valve at the cut portion inside the housing; and sequentially closing the ports with the valve body, and removing the existing fluid pipe connected to the opening communicating with the port, or connecting the new fluid pipe to the opening.
According to this feature, by blocking one of the ports formed in an approximately cross-shaped manner with a valve body, an uninterrupted flow state can be maintained through the remaining three ports that are open, while the existing fluid pipe connected to the opening side that communicates with the port whose valve body is blocked can be removed and a new fluid pipe can be laid in sequence, making it possible to update multiple fluid pipes and providing high construction scalability.

The opening of the housing is characterized in that an upstream fluid pipe and a downstream fluid pipe are connected as new fluid pipes.
According to this feature, a new flow path can be secured by the newly installed fluid pipe, regardless of whether or not the existing fluid pipe fitted onto the housing is removed.

FIG. 1 is a schematic diagram showing the laying status of existing pipes in a water supply facility in an embodiment. 1 is a schematic diagram showing the installation status of a fluid pipe in a waterworks facility in which a switching valve device of the present invention has been installed and part of the pipe has been replaced with a new pipe. This is a schematic diagram showing the installation status of fluid pipes in a water supply facility, some of which have been replaced with new pipes. FIG. 1 is a schematic diagram showing the installation status of fluid pipes in a waterworks facility after certain existing pipes have been removed. This is a schematic diagram showing the installation status of fluid pipes in a water supply facility after replacing existing pipes with new pipes. FIG. 10 is a side view showing an embodiment in which a working valve and a pipe cutting device are installed in a housing. FIG. 10 is a side view showing an embodiment in which an operating valve and a valve member insertion device are installed in a housing. 1A is a top view showing a switching valve device, and FIG. 1B is a side view and a partial cross-sectional view showing the switching valve device. This shows a cross-sectional view taken along line AA in FIG. (a) shows a state in which port 9C is blocked by the arc portion of the valve body, (b) shows a state in which port 9D is blocked by the arc portion of the valve body, and (c) shows a state in which port 9A is blocked by the arc portion of the valve body. (a) shows the state in which the valve stem is rotated to the left, (b) shows the state in which the valve stem is rotated 90 degrees from (a), and (c) shows the state in which the valve stem is rotated 90 degrees from (b). 1A is a cross-sectional view of a valve device in which a stopper member is attached to the bottom surface of a housing instead of a restricting member, and FIG. 1B is a view taken along the arrow C. FIG.

The following describes, based on examples, the embodiments of the switching valve device and pipe laying method using the device according to the present invention.

A switching valve device according to an embodiment and a pipe-laying method using the device will be described with reference to Figures 1 to 11. First, using Figure 1, an existing flow path will be described before the switching valve device is applied. Figure 1 shows a schematic diagram of a water purification facility, in this case a water distribution plant, in which multiple tanks A to C are installed, each capable of storing clean water (hereinafter also referred to as fluid) that has been purified by a treatment device or the like (not shown). Tank A and Tank B are connected by an existing fluid pipe (hereinafter simply referred to as existing pipe) 10 so that the fluid within the tanks can flow, and Tank B and Tank C are connected by an existing pipe 11 so that the fluid within the tanks can flow.

Existing pipe 14 is connected to tank C, which is connected to a branch pipe (not shown) downstream (towards point Y in Figure 1) outside the water treatment facility, for distribution to homes and other facilities. Existing pipe 13, extending from tank B, is connected to existing pipe 14 near the junction between tank C and existing pipe 14. Existing pipe 12, extending from tank A, is also connected to existing pipe 13 near the junction between tank B and existing pipe 13. In other words, the drinking water stored in tanks A through C is collected in existing pipe 14 and discharged downstream. Each of existing pipes 10 through 14 is actually constructed by connecting multiple pipe components (not shown) in the pipeline direction using flanges, welding, or other methods. Additionally, there are multiple other pipes within the facility, including a pump room, water tower, valve chest, and electrical and power line piping.

In this embodiment, the existing pipes 10-14 installed in such a water purification facility have reached the end of their useful life, and for convenience in the service area, designated locations are replaced with new fluid pipes (hereinafter simply referred to as new pipes) without interrupting flow. In this embodiment, the fluid in the fluid pipes is clean water. However, this is not limited to clean water. It may also be industrial water, agricultural water, sewage, gas, or a gas-liquid mixture. Furthermore, the existing pipes 10-14 and the new pipes described below are made of ductile cast iron, have a generally circular cross section, and have their inner surfaces coated with an epoxy resin layer. The new pipes of the present invention may also be made of other metals such as steel, concrete, vinyl chloride, polyethylene, or polyolefin. Furthermore, the inner surface of the new pipe is not limited to an epoxy resin layer; it may be coated with, for example, mortar, or a suitable material powder coated onto the inner surface of the new pipe.

First, at point Z, downstream of the connection point of the existing pipe 14 with the existing pipe 13 shown in FIG. 1, the outer surface of the existing pipe 14 is cleaned, and a housing 5 having a divided structure is then hermetically fitted onto the existing pipe 14. Regarding the housing 5, as shown in FIGS. 6 and 8(b), the housing 5 is primarily composed of a first divided body 55 constituting the upper portion and a second divided body 56 constituting the lower portion. While the housing is divided vertically in this embodiment, this is not limiting and any other division may be made along the diameter of the fluid pipe. For example, the housing may be divided horizontally, or the number of divisions may be three or more. The housing 5 has four openings 5A, 5B, 5C, and 5D, each equipped with a cylindrical sleeve at each end, to which a fluid pipe can be connected. These openings 5A-5D are connected within the housing 5 and branch off into a roughly cross-shaped configuration when viewed from above, as shown in FIG. 8(a). Linearly arranged openings 5A and 5C are fitted onto the exterior of the existing straight pipe 14, with flanges at their ends and split pressure rings to prevent separation. A sealing member, such as a pipe cap D, is attached to opening 5D of the housing 5, which faces the outer diameter of the existing pipe 14. The piping connected to opening 5B will be described later. Openings 5B and 5D are intended to be spigots for connecting earthquake-resistant pipes, such as NS and GX pipes, but they may also be sockets or equipped with flanges.

The openings 5A and 5D, which are arranged to intersect, are connected by a bypass pipe 58 equipped with a gate valve 58a, and the openings 5C and 5B, which are also arranged to intersect, are connected by a bypass pipe 57 equipped with a gate valve 57a. By switching the gate valves 58a and 57a to an open state, the fluid in the fluid pipe connected to one opening can be sent through the bypass pipes 58 and 57 to the fluid pipe connected to the other opening.

Next, at point Y, which is downstream of point Z of the existing pipe 14 shown in Figure 1, the outer surface of the existing pipe 14 is cleaned, and a housing 3 with a divided structure is fitted over it in a sealed manner. The housing 3 has three openings 3A, 3B, and 3C, each with a cylindrical sleeve portion in three horizontal directions and capable of connecting fluid pipes. These openings 3A to 3C are connected within the housing 3 and branch out in a roughly T-shape when viewed from above. Openings 3A and 3C, which are arranged in a straight line, are fitted over the existing pipe 14, and a pipe cap or other sealing member (not shown) is attached to opening 3B, which faces outward from the existing pipe 14.

As shown in Figure 8(b), the upper part of the housing 5 has an opening 5e that communicates with the interior of the housing 5, and an upper flange 50 formed around the edge of the opening 5e, allowing a tube cutting device, valve member insertion device, etc., to be attached above the upper flange 50. Furthermore, multiple drain holes 50b are formed in the lower part of the housing 5. Plugs or valves V can be connected to these drain holes 50b, allowing the fluid that fills the interior of the housing 5 to be drained through a series of operations described below. While the housing 3 is not shown, it has an opening in the upper part and drain holes in the lower part, just like the housing 5.

As shown in Figure 2, one side of the new pipe 21 is connected to the opening 5B of the housing 5, which is fitted over the existing pipe 14 at point Z. The new pipe 21 may be a short pipe extending from the housing 5 toward the housing 3. A valve 4 capable of switching the interior of the new pipe 21 between open and closed is disposed at the other end of the new pipe 21, and the other end of the new pipe 21 is kept closed by the valve 4. The valve 4 may also be installed at the opening 5B.

Next, as shown in Figure 6, the process moves to cutting the existing pipe 14 inside the housing 5 using a pipe cutting device 7. First, an operating valve 6 capable of opening and closing the upper flange portion 50 of the housing 5 is attached to the upper flange portion 50. The operating valve 6 is primarily composed of a valve box 61 that is sealed and connected to the opening 5e of the upper flange portion 50, a valve cover 62 that is sealed and connected to the side of the valve box 61, and a valve element (not shown) that is slidably arranged between the valve box 61 and the valve cover 62.

In other words, the working valve 6 is structured so that when the valve disc is placed in the valve box 61, it hermetically closes the housing 5, and when the valve disc is placed in the valve lid 62, it opens the housing 5.

Next, a pipe cutting device 7 is installed above the working valve 6 to cut the existing pipe 14. The pipe cutting device 7 is connected in a sealed state to the valve box 61 via a short pipe and is primarily composed of a mounting flange tube 71 that penetrates vertically, a cutter 72 disposed within the mounting flange tube 71, and a drive mechanism 73 for moving the cutter 72 vertically and rotating it circumferentially.

Furthermore, the cutter 72 provided in the pipe cutting device 7 of this embodiment is configured as a so-called hole saw and is formed in a cylindrical shape with a larger diameter than the existing pipe 14. While a hole saw is configured as the means for cutting the existing pipe 14 in this embodiment, this is not limited to this, and other means such as a cutting tool, wire saw, or end mill may also be used. In this case, if the pipe cutting device is a cutting tool, it is preferable to adopt a well-known method, such as a structure that rotates a sprocket or chain in the circumferential direction of the pipe, or a structure that moves the housing 5 in the axial or circumferential direction if the pipe cutting device is an end mill. Furthermore, while this embodiment cuts the existing pipe 14 so as to divide it in the pipe axial direction, this is not limited to this, and the existing pipe 14 may be cut so as to perforate a portion of the pipe wall without dividing it in the pipe axial direction.

Next, although not specifically shown, the valve element of the working valve 6 is retracted into the valve cover 62 to open the opening 5e, and the cutter 72 is rotated and advanced downward by the drive mechanism 73 using the pipe cutting device 7 described above, cutting the pipe without interrupting the flow. Because the cutter 72 is cylindrical, the cut end of the existing pipe 14 is formed into an arc shape that follows the cylindrical shape of the cutter when viewed from the cylindrical axial direction of the cutter 72. Furthermore, the cut pieces of the existing pipe 14 are contained inside the cylindrical cutter 72 and can be collected. Cutting chips generated when cutting the existing pipe 14 are discharged along with the fluid by operating valve V located at the bottom of the housing 5.

After the existing pipe 14 has been cut, the cutter 72 is raised, the valve body of the working valve 6 is placed inside the valve box 61, and the upper part of the housing 5 is closed. As a result, the existing pipe 14 is sealed inside the housing 5 in its cut state. The pipe cutting device 7 is then removed from the working valve 6, completing the cutting of the existing pipe 14.

By cutting the existing pipe 14 inside the fitted housing 5 at point Z, fluid flows into the new pipe 21 through opening 5B, but the other end of the new pipe 21 is connected to valve 4 in a closed state, preventing the fluid from leaking to the outside. Furthermore, by cutting the existing pipe 14, it is divided into multiple parts: existing pipe 14a connected to opening 5A of the housing 5, and existing pipe 14b connected to opening 5C of the housing 5 (see Figure 2). Even with the cutting of the existing pipe 14, fluid supplied from tanks A-C continues to flow downstream through existing pipe 14a, housing 5, and existing pipe 14b, maintaining an uninterrupted flow.

Next, the process moves to the step of sealingly installing the valve element 9 (switching valve) in the cutting section inside the housing 5. As shown in Figure 7, an insertion device 8 is sealedly attached to the top of the working valve 6 in place of the pipe cutting device 7. This insertion device 8 is sealedly connected to the valve box 61 via a short pipe and communicates with it. It primarily comprises an insertion device housing 81 that penetrates vertically, an insertion shaft 82 disposed within the insertion device housing 81, and a holding portion 83 disposed at one end of the insertion shaft 82 that holds the valve element 9 (described below). The insertion shaft 82 is raised and lowered by operating an operating portion (not shown) attached to the insertion shaft 82, and the valve element 9 is inserted into the housing 5 from above. It is recommended that the operating portion 94 (described below) be removed during insertion.

Then, after the valve element 9 is installed into the housing 5 using the insertion device 8, multiple fixing members 52, such as screws, arranged circumferentially near the top end of the housing 5 are screwed into the inner diameter of the housing 5, and the tips of these fixing members 52 are pressed against the outer surface of the inner valve box 91 to secure it in place. In this state, the upper inner surface of the housing 5 and the valve element 9 are sealed by a sealing member 59 arranged annularly on the outer surface of the inner valve box 91, as shown in Figure 8(b). The fluid inside the insertion device 8 is then drained, the retention member 83 and the insertion shaft 82 are released from the locking mechanism via an access hole (not shown), and the insertion device 8 is removed from the operating valve 6, which in turn is removed from the housing 5. The upper cover 51 is then attached to the upper flange 50 of the housing 5 and screwed downward using the fixing members 54, completing the insertion of the valve element 9. With the insertion process complete, the housing 5 and the valve element 9 function as a switching valve device 1.

As shown in Figure 9, the above-mentioned valve member 9 is formed in a generally cylindrical shape when viewed from above, with ports 9A, 9B, 9C, and 9D formed in the side walls in a generally cross-shaped manner, and is mainly composed of an inner valve box 91 (valve box) in which these ports 9A to 9D are connected internally, valve shafts 93a and 93b erected coaxially and vertically at the top and bottom of the inner valve box 91 at approximately the center position, a valve body 92 fixedly attached to the valve shafts 93a and 93b, an operating part 94 for rotating the valve shafts 93a and 93b, a restricting member 95 for restricting the movement of the valve body 92, and a cover member 96. The valve element 92 is mainly composed of an upper plate 92b connected to the valve stem 93a and having a generally fan-shaped configuration in plan view, a lower plate 92c connected to the valve stem 93b and having a shape generally identical to that of the upper plate 92b, and an arc-shaped portion 92a formed in a plan view around the valve stems 93a and 93b, curving vertically between the outer diameter end of the upper plate 92b and the outer diameter end of the lower plate 92c. The valve element 92 is molded by casting, and its outer surface is covered with an elastic body (see FIG. 8(b)). The elastic body is made of rubber, elastomer, resin, or the like, including NBR, SBR, and CR. The outer peripheral surface of the arc-shaped portion 92a has fins that seal the ports 9A to 9D and enable them to be sealed using the inner surface of the inner valve box 91. After the valve element 9 is installed in the housing 5, the upper end of the valve stem 93a projects loosely through a cylindrical portion 94a surrounding an insertion hole in the top cover 51, and an operating portion 94 is attached to the projecting portion. Operating the operating portion 94 rotates the valve element 92, allowing the valve element 92 to selectively close ports 9A, 9C, and 9D. Furthermore, because the valve stems 93a and 93b are spaced apart vertically, the approximate center area of the valve element 92 is secured as a fluid flow area. When inserting the valve element 9, the valve element 9 is inserted so that ports 9A, 9B, 9C, and 9D of the inner valve box 91 communicate with openings 5A, 5B, 5C, and 5D of the housing 5, respectively, and the arc portion 92a of the valve element 92 is inserted toward port 9D, i.e., opening 5D of the housing 5 (see Figure 2).

As shown in Figures 11(a) to (c), by attaching the operating part 94 to the valve shaft 93a, the valve shaft 93a is surrounded by the cylindrical part 94a and the restricting member 95. The outer peripheral surface of the valve shaft 93a is covered by a cover member 96, and by operating the operating part 94, the valve shaft 93a and the cover member 96 rotate integrally within the cylindrical part 94a. Furthermore, the cross-sectional shape of the cover member 96 is such that a portion of its periphery protrudes due to its protrusion 96a, i.e., it has an eccentric, approximately elliptical shape.

The tubular portion 94a is formed in a generally cylindrical shape with a portion cut out in the circumferential direction, and a restricting member 95 is disposed in the cut-out portion. The restricting member 95 is generally rectangular in plan view, and has a recess 95c formed in the approximate center on the valve shaft 93a side that is recessed toward the outer diameter side of the tubular portion 51a. The restricting member 95 has screws 95a and 95b as adjustment members that are threaded from the outer diameter side to the inner diameter side of the tubular portion 94a, and the flat tip ends of the screws 95a and 95b pass through the restricting member 95 and protrude into the interior of the tubular portion 94a. The amount by which the tip ends protrude into the interior of the tubular portion 94a can be adjusted by appropriately threading the screws 95a and 95b.

For example, when the operating unit 94 is operated from the state shown in FIG. 11(b) to the state shown in FIG. 11(a) and the protruding portion 96a of the cover member 96 attached to the valve shaft 93a is turned leftward, the arc portion 92a of the valve body 92, which is formed in a roughly fan shape, is turned leftward along with the valve shaft 93a, as shown in FIG. 10(a). In other words, the protruding portion 96a of the cover member 96 and the arc portion 92a of the valve body 92 are located at the same circumferential position. At this time, one side portion 96L of the protruding portion 96a abuts against the tip of the screw 95a protruding from the restricting member 95, thereby restricting rotation while adjusting for slight rotational allowance.

Furthermore, when the operating unit 94 is operated from the state shown in Figure 11(b) as shown in Figure 11(c) and the valve shaft 93a is turned to the right, the arc portion 92a of the valve body 92 is turned to the right along with the valve shaft 93a, as shown in Figure 10(c). The inner valve box 91 is formed with side wall steps 91a to 91d that extend from the bottom to the top. The side wall steps 91a to 91d may also protrude toward the valve shaft 93. Furthermore, as shown in Figure 9, sealing members 53a to 53d that seal the inner surface of the housing 5 are arranged in the vertical direction on the outer surfaces of each of the side wall steps 91a to 91d. These sealing members 53a-53d seal the inner surface of the housing 5 and the outer surface of the inner valve box 91. They are integrally formed with the sealing member 59 and are also integrally formed with the outer bottom surface of the inner valve box 91. By sealing the inner surface of the housing 5 between each of the ports 9A-9D of the inner valve box 91 and the outer surface of the inner valve box 91, each port is hermetically separated. Note that the sealing members 59 and 53a-53d are not limited to being integrally formed. As shown in FIG. 10(a), when the arc portion 92a of the valve body 92 is turned counterclockwise to the left in the figure, the arc portion 92a abuts against the side wall steps 91c and 91d, sealing and closing the port 9C. At this time, one side portion 96L of the protruding portion 96a abuts against the tip of the screw 95a protruding from the restricting member 95, restricting further counterclockwise rotation. 10(b), when the arcuate portion 92a of the valve body 92 is turned upward in the figure, the arcuate portion 92a abuts against the side wall steps 91a and 91d, forming a seal, and closing the port 9D. Furthermore, as shown in FIG. 10(c), when the arcuate portion 92a of the valve body 92 is turned clockwise to the right in the figure, the arcuate portion 92a abuts against the side wall steps 91a and 91b, forming a seal, and closing the port 9A. At this time, the other side portion 96R of the protrusion 96a abuts against the tip of the screw 95b protruding from the restricting member 95, restricting further clockwise rotation. In this embodiment, a restricting member 95 is fixed to a portion of the circumference of the cylindrical portion 94a shown in Figures 11(a) to 11(c), and as shown in Figures 10(a) to 10(c), the arc portion 92a of the valve body 92 is restricted from moving from ports 9A and 9C toward port 9B, and is unable to rotate near port 9B. In other words, port 9B is a specific port according to the present invention.

In addition, a restricting member 95 is fixed to a portion of the circumference of the tubular portion 94a of the valve element 92 as shown in Figures 11(a) to (c), allowing the valve element 92 to rotate approximately 180 degrees clockwise from port 9C to port 9A, or counterclockwise from port 9A to port 9C. Furthermore, because the valve element 92 has a fan shape that extends approximately 90 degrees when viewed from above, it is possible to block the approximately 270-degree area extending from side wall step 91a to side wall step 91b.

In addition, a recess 95c is formed in the restricting member 95, allowing the rear end 96b of the arc-shaped cover member 96 to rotate smoothly without being hindered. After rotating the valve shaft 93 to a desired position, the tip of the fixing screw 94b, which can move from the outer diameter side of the cylindrical portion 94a toward the inner diameter side, is pressed against the flat portions H formed on each of the four sides of the cover member 96, thereby fixing the valve body 92 in place.

Next, the process of connecting a new fluid pipe will be described. As shown in Figure 2, a new pipe 20 is laid from tank A toward the opening 5D of the housing 5 attached to point Z of the existing pipe 14. It is recommended that the new pipe 20 be cleaned when laying it. For example, the inside of the new pipe 20 may be cleaned using a pipe cleaning pig (not shown). It will be assumed that the new pipe laid in place of the existing pipe has been cleaned using the above-mentioned pipe cleaning procedure. The timing of the pipe cleaning is not limited to this.

With the arc portion 92a of the valve body 92 blocking the port 9D, the pipe cap D attached to the opening 5D of the housing 5 is removed, one end of the new pipe 20 is connected, and the other end of the new pipe 20 is connected to a valve unit (not shown) on the tank A. The valve unit is closed beforehand, and a pressure test of the new pipe 20 is performed before opening it. When performing the pressure test of the new pipe 20, fluid is supplied through a supply port (not shown) of the new pipe 20. Once favorable test results are confirmed in the pressure test, the gate valve 58a of the bypass pipe 58 connecting the openings 5A and 5D is switched to the open state, as shown in Figure 8(a), and the fluid in the existing pipe 14a is allowed to flow into the new pipe 20 while performing air venting, etc. This fills the new pipe 20 with fluid, and the fluid pressure inside the new pipe 20 and the fluid pressure inside the inner valve box 91 become approximately equal, which almost eliminates the pressure difference acting on the arc portion 92a of the valve element 92, making it easier to rotate the valve element 92. In addition, since the fluid inside the existing pipe 14a flows into the new pipe 20 via the bypass pipe 58, a decrease in flow rate is prevented, preventing the water hammer phenomenon that may occur when the valve element 92 is opened or closed. The timing of the pressure test is not limited to this.

Next, one end of the new pipe 22 is connected to the valve 4 located at the end of the new pipe 21, and the other end of the new pipe 22 is connected to the opening 3B of the housing 3 installed at point Y of the existing pipe 14. As with the new pipe 20 described above, the new pipe 22 is also subjected to pipe cleaning and pressure testing. After this, the valve 4 is switched to an open state, and fluid may be allowed to flow into the new pipe 22 while performing air purging, or an inflow may be performed as described below.

Next, the process moves to attaching the work valve 6 to the housing 3 installed at point Y of the existing pipe 14b in the same manner as described above, and cutting the existing pipe 14b using the pipe cutting device 7. Note that as this is the same as the cutting process described above, detailed explanation will be omitted. By cutting the existing pipe 14b inside the housing 3 using the pipe cutting device 7, the existing pipe 14b is separated into existing pipe 14b', which is connected at one end to opening 5C of housing 5 and opening 3A of housing 3, and existing pipe 14c, which is connected to opening 3C of housing 3 and connected to a downstream branch pipe (not shown) (see Figure 2). Furthermore, an uninterrupted flow state is maintained during this cutting process.

After the cutting process of existing pipe 14b at point Y, valve 4 is switched to the open state. As a result, the fluid supplied from tanks A to C via existing pipes 12, 13, and 14a flows into housing 5 and branches toward existing pipe 14b' via opening 5C and toward new pipe 21 via opening 5B. The branched fluids converge in housing 3 installed at point Y and flow downstream through existing pipe 14c.

Next, the insertion device 8 is used to install the partition member 30 within the housing 3. The installation of the partition member 30 is performed using the same procedure as the installation of the valve member 9 described above, and therefore a detailed description will be omitted. The partition member 30 installed within the housing 3 comprises a partition body 31 that connects opening 3B with opening 3C, one of openings 3A to 3C of the housing 3, and blocks opening 3A. The front side of this partition body 31 is formed with an arc-shaped tapered surface that is recessed toward the inner diameter. By positioning the front side of the partition body 31 so that the opening areas of openings 3B and 3C remain, fluid flowing in from opening 3B flows smoothly out toward opening 3C. The rear side of partition 31 forms a closed area that closes the opening, and by positioning the front side of partition 31 so that the opening areas for openings 3B and 3C remain, the rear side of partition 31 closes opening 3A of housing 3 and releases communication downstream of opening 5C of housing 5 at point Z (see Figure 2). Partition member 30 may also be a switching valve.

Next, as shown in Figure 3, the operating part 94 of the valve member 9 is operated to rotate the valve body 92 toward opening 5C, thereby blocking the inflow of fluid into the existing pipe 14b'. By rotating the valve body 92 toward opening 5C, fluid from tank A passes through new pipe 20, opening 5D of the housing 5, and opening 5B, then passes through new pipe 21, new pipe 22, openings 3B and 3C of the housing 3, and the existing pipe 14c, before flowing downstream. Fluid from tanks A to C also flows into the housing 5 by passing through existing pipes 12, 13, and 14a, and opening 5A.

As shown in Figure 9, the opening angle α formed in a plan view by the sealing members 53b, 53c and 53d, 53a sealing the two opposing ports 9B and 9D on a straight line formed in the inner valve box 91 is smaller than the opening angle β formed by the sealing members 53a, 53b and 53c, 53d sealing the two opposing ports 9A and 9C perpendicular to these ports (α < β). The existing pipe 14 is connected to the ports 9A and 9C with the relatively larger opening angle, and the new pipes 20 and 21 are connected to the ports 9B and 9D with the relatively smaller opening angle. This minimizes the impact of the fluid in the new pipe 20 connected to the opening 5D communicating with the port 9D with the smaller opening angle when rotating the valve body 92 from port 9D to port 9C or filling the new pipe 20 with water. In particular, in this embodiment, after connecting the new pipe 20, a new pressure flow is applied, so there is a risk of unexpected effects such as a force pressing on the inner valve box 91 from the new pipe 20 side, a pulling force due to the flow path through the existing pipe 14, the water hammer phenomenon, and flow velocity effects. However, by making the opening angle α smaller than the opening angle β, the support force of the inner valve box 91 to the housing 5 can be set high. The opening widths of each port 9A to 9D perpendicular to the flow path direction are formed to be approximately the same, and the opening areas are also formed to be approximately the same. The shape of each port may be approximately rectangular or approximately circular when viewed from the side.

Returning to Figure 2, fluid is stagnating within the existing pipe 14b'. First, the fluid is drained from a drain outlet (not shown) installed in the existing pipe 14b'. After draining, the existing pipe 14b' is cut or the axial engagement between the fluid pipes that make up the existing pipe 14b' is disengaged so that the existing pipe 14b' can be replaced with a new pipe. The opening 5C of the housing 5 and the end of the cut or disengaged existing pipe 14b' extending from the opening 3A of the housing 3 are each covered with a pipe cap D (see Figure 3). Furthermore, the gate valve 57a of the bypass pipe 57 connecting the openings 5B and 5C is switched to an open state, allowing the fluid in the new pipe 21 to flow into the existing pipe 14b'. This fills the existing pipe 14b' with fluid, making the fluid pressure in the existing pipe 14b' and the fluid pressure in the internal valve box 91 approximately equal, making it easier to rotate the valve element 92. The existing pipe 14b' connected to the opening 5C of the housing 5 and the existing pipe 14b' connected to the opening 3A of the housing 3 may be removed and the openings plugged.

Next, to replace the existing pipes 10-13, 14a shown in Figure 3 with new pipes, the valve element 92 is rotated approximately half a turn clockwise from port 9C to close port 9A. When the operating part 94 is operated to rotate the valve element 92, a restricting member 95 is provided as shown in Figures 11(a) to (c) to restrict counterclockwise rotation. Therefore, port 9D is passed through the arc portion 92a of the valve element 92 as shown in Figure 10(b), and the operating part 94 is then operated to cause the arc portion 92a of the valve element 92 to close port 9A as shown in Figure 10(c). As a result, the restricting member 95 prevents the arc portion 92a of the valve body 92 from blocking port 9B, which communicates with opening 5B, and prevents passage over port 9B, preventing a flow cutoff caused by an accidental blockage. In this case, the valve body 92 temporarily crosses port 9D, but because there is inflow from the existing pipe 14a, an uninterrupted flow state can be maintained.

As described above, by rotating valve element 92 from opening 5C to opening 5A and closing port 9A, the fluid supplied from tank A passes through new pipe 20, opening 5D of housing 5, and opening 5B, then passes through new pipes 21 and 22, openings 3B and 3C of housing 3, and existing pipe 14c, before flowing downstream, maintaining an uninterrupted flow. As shown in Figure 4, existing pipes 10-13 are removed, and end 14a' of existing pipe 14a is covered with pipe cap D. Alternatively, existing pipe 14a may be removed and opening 5A plugged.

Next, as shown in FIG. 5, Tank A and Tank B are connected by new pipe 23, allowing fluid to flow between the tanks, and Tank B and Tank C are connected by new pipe 24, allowing fluid to flow between the tanks. Furthermore, pipe cap D covering existing pipe 14a' is removed, and new pipe 25 is installed via a joint ring (not shown). New pipe 25 consists of branch pipe 25a connected to Tank C and branch pipe 25b connected to Tank B, and connects Tank B and Tank C to opening 5A of housing 5. Furthermore, gate valve 58a of bypass pipe 58 connecting opening 5A and opening 5D is switched to an open state, allowing fluid from the inner valve box 91 to flow into new pipe 25. This fills new pipe 25 with fluid, making the fluid pressure in new pipe 25 and the fluid pressure in the inner valve box 91 approximately equal, making it easier to rotate valve element 92.

Finally, as shown in the dashed-dotted box in Figure 5, the valve element 92 is rotated counterclockwise from port 9A to close port 9C. This allows fluid to flow into the switching valve device 1 from port 9A on the previously closed opening 5A side, allowing fluid supplied from tanks A to C on the upstream side to flow in through openings 5A and 5D of the housing 5 and fluid to flow out downstream through opening 5B. This concludes the explanation of an example of replacement work from an existing pipe to a new pipe in a water supply facility using the switching valve device 1.

Figures 12(a) and (b) show a switching valve device 100 equipped with a switching valve 190. This is a modified example in which, instead of the restricting member 95 of the previous embodiment, stopper members 40, 41, which are formed in a roughly T-shape when viewed from above and serve as restricting members in this case, are disposed at two locations on the bottom surface 50a of the inner valve box 105. The stopper members 40, 41 are formed from steel, and their bottom surfaces are fixed to the bottom surface 50a of the inner valve box 105 by welding or the like. In this modified example, the stopper members 40, 41 are disposed on the lower side within the inner valve box 105 in Figure 12(a), thereby restricting rotation toward port 9B in the same way as the restricting member 95 described above.

The stopper members 40, 41 are generally T-shaped when viewed from above, and extend generally vertically upward from a bottom portion fixed to the bottom surface 50a of the inner valve box 105. Each stopper member is formed with a restricting portion 40a, 41a, which is a wide abutment surface. When the valve shafts 193a, 193b of the switching valve 190 are operated by an operating unit (not shown) and the valve element 192 is rotated, the restricting portion 40a of the stopper member 40 or the restricting portion 41a of the stopper member 41 abuts against the lower plate 192c of the valve element 192, thereby restricting rotation toward port 9B.

As described above, the switching valve device 1 comprises a split housing 5 with openings 5A-5D for connecting fluid pipes, which fits tightly around an existing pipe, and a switching valve 9 that is installed in a sealed manner within the housing 5 at a section of the existing pipe where the pipe has been severed. This allows for the connection of a new pipe to the housing 5 without interrupting the flow of the fluid. The housing 5 has openings 5A-5D formed in a roughly cross-shaped configuration. The switching valve 9 has an inner valve case 91 with ports 9A-9D formed in a roughly cross-shaped configuration that communicate with the openings 5A-5D, respectively, and a valve element 92 that can selectively close one port. By closing one of the ports 9A-9D formed in a roughly cross-shaped configuration with the valve element 92, the flow is maintained uninterrupted through the remaining three open ports. This allows for the sequential removal of the existing pipe connected to the opening that connects to the port with the valve element 92 closed, and the installation of a new fluid pipe. This allows for the replacement of multiple fluid pipes and provides high construction scalability.

The inner valve box 91 is provided with a restricting member 95 that prevents the valve element 92 from closing a specific port 9B among the ports 9A to 9D. This restricting member 95 allows the specific port 9B to remain open at all times, thereby maintaining an uninterrupted flow in the fluid pipe connected to the opening 5B that communicates with this port 9B and preventing a flow interruption due to accidental blockage.

Furthermore, the valve element 92 is rotatable around a rotation axis located in the center of the switching valve 9, and the rotation angle of the valve element 92 is restricted to within 270 degrees by the restricting member 95, thereby blocking ports 9A, 9B, and 9D except for the specific port 9B.Since the restricting member 95 restricts the valve element 92 from passing through the specific port 9B, a temporary flow interruption that occurs when the valve element 95 passes through can be prevented.

Furthermore, of the ports formed in a generally cross-shaped configuration, the opening angle α formed in a plan view by the sealing members 53b, 53c and 53d, 53a sealing the opposing pair of ports 9B, 9D is smaller than the opening angle β formed by the sealing members 53a, 53b and 53c, 53d sealing the remaining pair of ports 9A, 9C that are generally perpendicular to the first pair (α < β). Therefore, the influence of the fluid in the fluid pipe connected to the openings 5B, 5D that communicate with the ports 9B, 9D with the smaller opening angle can be minimized.

This pipe installation method uses a switching valve device (1) to install a new fluid pipe without interrupting the flow. It involves the steps of: sealingly fitting a housing (5) onto an existing pipe (14); cutting a portion of the existing pipe (14) inside the housing (5) while closing opening (5D) of the housing (5) for connecting a new pipe (20); installing a switching valve (9) at the cut section inside the housing (5); and sequentially closing ports with a valve (92) and removing the existing pipe connected to the opening communicating with the port, or connecting a new pipe to the opening. By closing one of the ports arranged in a roughly cross shape with the valve (92), the existing pipe connected to the opening communicating with the port with the closed valve (92) can be sequentially removed or a new pipe laid, while maintaining an uninterrupted flow through the remaining three open ports. This allows for the renewal of multiple fluid pipes, resulting in high construction scalability.

Furthermore, new pipes 20 and 25 are connected to openings 5A to 5D of housing 5 as new upstream fluid pipes, and new pipe 21 is connected to the new downstream fluid pipe. Therefore, new pipes 20, 21, and 25 can secure new flow paths regardless of whether or not the existing fluid pipe 14 fitted onto the housing 5 is removed.

Although embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions that do not deviate from the gist of the present invention are also included in the present invention.

For example, in the above embodiment, the switching valve device 1 is installed in an existing pipeline installed in a water purification facility, and the process of replacing it with a new pipe is described in order, but this is not limited to this. Some steps may be omitted or modified as long as the replacement with a new pipe can be performed while maintaining an uninterrupted flow. Furthermore, the switching valve device of the present invention can be applied not only to water purification facilities, but also to various facilities where existing pipelines are configured.

In addition, in the above embodiment, the restricting member 95 and stopper members 40, 41 are used to restrict the valve body 92 from closing port 9B, but this is not limited to this. As long as the replacement pipe is installed with a new pipe while maintaining an uninterrupted flow state, the closing of other ports may be restricted. Also, no restriction is required.

In addition, in the above example, both the upstream and downstream sides were connected to the new pipe, but for example, both upstream sides could be connected to the new pipe, or both downstream sides could be connected to the new pipe.

1 Switching valve device 3 Housing 3A to 3C Opening 4 Valve 5 Housing 5A to 5D Opening 6 Working valve 7 Pipe cutting device 8 Insertion device 9 Valve member (switching valve)
9A to 9D Ports 9B Specific ports 10 to 14 Existing pipes 20 to 25 New pipes 30 Partition member 31 Partition body 40 Stopper member (restriction member)
41 Stopper member (regulating member)
53a to 53d Sealing member 91 Inner valve box (valve box)
92 Valve body 92a Arc portions 93a, 93b Valve stem 94 Operating portion 95 Restricting member 96 Cover member

Claims (3)

A switching valve device for connecting a new fluid pipe to the housing in an uninterrupted flow state, the switching valve comprising a housing with a split structure that is fitted tightly onto an existing fluid pipe, and a switching valve that is sealed and installed in the housing at a cut portion where a part of the existing fluid pipe is cut,
The housing is formed with at least a pair of openings connected to existing fluid pipes and a first opening for connecting a newly installed fluid pipe, and is provided with at least a bypass pipe connecting one of the pair of openings to the first opening, both ends of the bypass pipe are connected to the bottom of the housing, and the bypass pipe is arranged in an approximately horizontal direction at a position below the housing . A switching valve device for connecting a new fluid pipe to the housing in an uninterrupted flow state, the switching valve comprising a housing with a split structure that is fitted tightly onto an existing fluid pipe, and a switching valve that is sealed and installed in the housing at a cut portion where a part of the existing fluid pipe is cut,
a switching valve device, characterized in that the housing is formed with a pair of openings connected to existing fluid pipes, a first opening for connecting a new fluid pipe , and a second opening different from the first opening for connecting the new fluid pipe; the switching valve device is provided with a bypass pipe connecting one of the pair of openings to the first opening, and a second bypass pipe connecting the other of the pair of openings to the second opening , the bypass pipe and the second bypass pipe being arranged in a substantially horizontal direction at substantially the same height position . A pipe laying method for laying a new fluid pipe under an uninterrupted flow condition using the switching valve device according to claim 1 or 2 , comprising:
a step of sealingly fitting the housing onto an existing fluid pipe; a step of cutting a portion of the existing fluid pipe inside the housing while closing an opening of the housing for connecting a new fluid pipe; a step of installing the switching valve at the cut portion inside the housing; a step of sequentially closing ports of the switching valve with the valve body of the switching valve, removing the existing fluid pipe connected to the opening communicating with the port, and connecting a new fluid pipe to the opening; and a step of connecting the housing and the new fluid pipe via the bypass pipe.