Switching valve device

Abstract

To provide a switching valve device having high expandability even when existing pipes are replaced with new pipes or new pipes are added under circumstances where a large number of existing pipes are laid. [Solution] A switching valve device 1 that connects a new pipe to the housing 5 without interrupting flow, comprising a housing 5 that fits over an existing pipe and a switching valve 9 that is installed inside the housing 5 at the cut section of the existing pipe, wherein the switching valve device 1 connects a new pipe to the housing 5 in a continuous flow state, the housing 5 having openings 5A and 5C that connect to the existing pipe and a first opening 5B for connecting the new fluid pipe, the switching valve 9 having a valve box 91 that has ports 9A and 9C that communicate with the openings 5A and 5C and a port 9B that communicates with the first opening 5B, a valve element 92 that can selectively close one of the ports 9A, 9B, and 9C, and a valve shaft 93b that is mounted on the valve box 91 and supports the valve element 92, and the opening angle β of the sealing members 53a and 53b of the ports 9A and 9C is greater than the opening angle α of the sealing members 53b and 53c of the port 9B that communicates with the first opening 5B.

Description

[Technical Field]

[0001] 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. [Background technology]

[0002] In construction work to update an existing water supply pipeline, for example, it is desirable to maintain an uninterrupted flow, i.e., a state in which water flows, for the convenience of water users. A conventional method for forming a flow path under an uninterrupted flow condition involves fitting a housing with a split structure to the existing fluid pipe in a sealed state, cutting the existing fluid pipe inside the housing, inserting a switching valve having a valve box and a valve element into the cut pipe section inside the housing, connecting a new pipe alongside the existing fluid pipe, and switching the flow path from the existing fluid pipe to the new pipe by opening and closing a port in the valve box by operating the valve element.

[0003] 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 many pipes connecting these and for distributing water downstream are laid close to each other. In recent years, in water treatment facilities where such many pipes are laid, multiple pipes have reached the end of their useful life at once and need to be replaced, or pipes need to be made earthquake-resistant to make them more resilient, or pipes need to be doubled in preparation for disasters. In particular, in water treatment facilities that handle domestic water, it is essential to replace existing fluid pipes with new fluid pipes or lay new fluid pipes under conditions of continuous flow.

[0004] An example of a switching valve device used in such a method of forming a flow path under uninterrupted flow conditions is one in which a valve box is housed in a housing with three openings, with three ports formed to be openable and closable. Two of the openings in the housing are connected to existing pipes that have been separated inside the housing, and the remaining opening can be connected to a new pipe. After the housing fitted over the existing pipe is connected to the new pipe, a valve element inside the valve box closes the port that communicates with the existing pipe on the downstream side, allowing fluid to flow from the existing pipe on the upstream side to the new pipe, and the existing pipe on the downstream side with its port closed can be removed or replaced under uninterrupted flow conditions (see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2011-75052 A (page 1, figure 1) Summary of the Invention [Problem to be solved by the invention]

[0006] 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, and if an existing flow path consisting of many existing pipes is to be replaced with a new pipe or a new pipe is to be added, using the switching valve device of Patent Document 1 requires the installation of multiple switching valve devices, which has low scalability, making the pipe laying work complicated and leading to increased costs.In addition, in this case, a large construction space is required, which makes construction impossible in some cases.

[0007] The present invention has been made in response to these problems, and aims to provide a highly expandable switching valve device and a pipe laying method using the device, even when multiple existing pipes are replaced with new pipes or new pipes are added in a situation where a large number of existing pipes are laid. [Means for solving the problem]

[0008] 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.

[0009] 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.

[0010] 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 closing off 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.

[0011] 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.

[0012] 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, 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.

[0013] 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. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram showing the laying status of existing pipes in a water supply facility in an embodiment. [Figure 2]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. [Figure 3] 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. [Figure 4] FIG. 1 is a schematic diagram showing the installation status of fluid pipes in a waterworks facility after certain existing pipes have been removed. [Figure 5] This is a schematic diagram showing the installation status of fluid pipes in a water supply facility after replacing existing pipes with new pipes. [Figure 6] FIG. 10 is a side view showing an embodiment in which a working valve and a pipe cutting device are installed in a housing. [Figure 7] 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. [Figure 8] FIG. 2A is a top view showing the switching valve device, and FIG. 2B is a side view and a partial cross-sectional view showing the switching valve device. [Figure 9] This shows a cross-sectional view taken along line AA in FIG. 8(b). [Figure 10] (a) shows a state in which port 9C is blocked by the arc portion of the valve disc, (b) shows a state in which port 9D is blocked by the arc portion of the valve disc, and (c) shows a state in which port 9A is blocked by the arc portion of the valve disc. [Figure 11] (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). [Figure 12] 1(a) is a cross-sectional view of a valve device in which a stopper member is attached to the bottom surface of the housing instead of a restricting member, and FIG. 1(b) is a view taken along the arrow C. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A switching valve device according to the present invention and a pipe laying method using the device will be described below with reference to the following examples. [Example]

[0016] A switching valve device according to an embodiment and a pipe-laying method using the device will be described with reference to Figs. 1 to 11. First, an existing flow path before the switching valve device is applied will be described with reference to Fig. 1. Fig. 1 shows a schematic diagram of a water purification facility, for example, 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 in the tanks can circulate, and tank B and tank C are connected by an existing pipe 11 so that the fluid in the tanks can circulate.

[0017] An existing pipe 14 is connected to Tank C, which is connected to a branch pipe (not shown) outside the water treatment facility downstream (point Y in Figure 1) for distribution to homes, etc. An existing pipe 13 extending from Tank B is connected to Existing Pipe 14 near the junction between Tank C and Existing Pipe 14. An 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 water stored in Tanks A-C is collected in Existing Pipe 14 and flows out downstream. Note that each of Existing Pipes 10-14 is actually constructed by connecting multiple pipe members (not shown) in the pipeline direction with flanges, welding, etc. In addition, there are multiple other pipes within the facility, such as a pump room, water tower, valve chest, and electrical and power line piping.

[0018] 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 of the service area, predetermined 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. For example, the fluid may 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 according to 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 such as powder coating.

[0019] First, the outer periphery of the existing pipe 14 is cleaned at point Z, which is downstream of the connection point of the existing pipe 14 with the existing pipe 13 shown in FIG. 1, and then a housing 5 having a divided structure is hermetically fitted onto the outer periphery. The housing 5 will now be described. 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 the housing may be divided in any direction along the diameter of the fluid pipe. For example, the housing may be divided horizontally, and 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 to 5D are connected within the housing 5 and branch off into a generally cross-shaped configuration in top view, as shown in FIG. 8(a). Openings 5A and 5C, which are arranged in a straight line, are fitted onto the outside of an existing pipe 14, each of which is fitted with a flange at its end and a split pressure ring to prevent it from coming loose. A pipe cap D, for example, is hermetically attached as a blocking member to opening 5D of housing 5, which faces the outer diameter of existing pipe 14. The piping to be connected to opening 5B will be described later. Openings 5B and 5D are spigots, such as NS and GX spigots, for connecting earthquake-resistant pipes, but they may also be sockets or equipped with flanges.

[0020] Furthermore, openings 5A and 5D, which are disposed so as to intersect, are connected by a bypass pipe 58 equipped with a gate valve 58a, and openings 5C and 5B, which are similarly disposed so as to intersect, are connected by a bypass pipe 57 equipped with a gate valve 57a. By switching gate valves 58a and 57a to an open state, the fluid in the fluid pipe connected to one opening can be sent through bypass pipes 58 and 57 to the fluid pipe connected to the other opening.

[0021] Next, at point Y, which is downstream of point Z of the existing pipe 14 shown in Figure 1, the outer circumferential 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 formed in three horizontal directions, each with a cylindrical sleeve portion and capable of connecting to a fluid pipe, and these openings 3A to 3C communicate within the housing 3 and are branched 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 the outer diameter of the existing pipe 14.

[0022] 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, so that a tube cutting device, a valve member insertion device, etc., described below, can be attached above the upper flange 50. Furthermore, a plurality of drain holes 50b are formed in the lower part of the housing 5. The drain holes 50b can be connected to plugs or valves V, and fluid that has filled the inside of the housing 5 can be drained through a series of operations described below. Although 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.

[0023] As shown in Figure 2, one side of a new pipe 21 is connected to an opening 5B of a housing 5 fitted onto the outside of the existing pipe 14 at point Z. The new pipe 21 may be a short pipe extending from the housing 5 towards 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 be installed at the opening 5B.

[0024] Next, as shown in Figure 6, the process moves to a step in which the existing pipe 14 inside the housing 5 is cut by a pipe cutting device 7. First, an operating valve 6 capable of opening and closing the upper flange portion 50 is attached to the upper flange portion 50 of the housing 5. The operating valve 6 is mainly composed of a valve box 61 that is connected in a sealed state to the opening 5e of the upper flange portion 50 in communication with it, a valve cover 62 that is connected in a sealed state to the side of the valve box 61 in communication with it, and a valve element (not shown) that is slidably arranged between the valve box 61 and the valve cover 62.

[0025] In other words, the working valve 6 is structured so that when the valve body is placed in the valve box 61, it hermetically closes the housing 5, and when the valve body is placed in the valve lid 62, it opens the housing 5.

[0026] Next, a pipe cutting device 7 for cutting the existing pipe 14 is installed above the working valve 6. The pipe cutting device 7 is connected in a sealed state in communication with the valve box 61 via a short pipe, and is mainly composed of a mounting flange cylinder 71 that penetrates in the vertical direction, a cutter 72 disposed within the mounting flange cylinder 71, and a drive mechanism 73 for moving the cutter 72 in the vertical direction and rotating it circumferentially.

[0027] 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 diameter larger than that of 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 thereto, and other means, such as a cutting tool, a wire saw, or an 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 thereto, 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.

[0028] Next, although not 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 to cut the existing pipe 14 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. 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 together with the fluid by operating valve V located at the bottom of the housing 5.

[0029] After the existing pipe 14 has been cut, the cutter 72 is raised and the valve body of the working valve 6 is placed inside the valve box 61, blocking the upper part of the housing 5. As a result, the existing pipe 14 is sealed in the housing 5 in a cut state. Thereafter, the pipe cutting device 7 is removed from the working valve 6, and the cutting operation of the existing pipe 14 is completed.

[0030] By cutting the existing pipe 14 inside the fitted casing 5 at point Z, the 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, the existing pipe 14 is divided into multiple parts: existing pipe 14a connected to opening 5A of the casing 5, and existing pipe 14b connected to opening 5C of the casing 5 (see FIG. 2). Even with the cutting of the existing pipe 14, the fluid supplied from tanks A to C continues to flow downstream through existing pipe 14a, casing 5, and existing pipe 14b, maintaining an uninterrupted flow state.

[0031] 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 FIG. 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 mainly comprises an insertion device housing 81 that penetrates vertically, an insertion shaft 82 disposed within the insertion device housing 81, and a holding part 83 that holds the valve element 9 (described later) disposed at one end of the insertion shaft 82. An operating part (not shown) attached to the insertion shaft 82 is operated to raise and lower the insertion shaft 82, and the valve element 9 is inserted into the housing 5 from above. During insertion, it is recommended that an operating part 94 (described later) be removed.

[0032] Then, after the valve element 9 is installed in the housing 5 using the insertion device 8, multiple fixing members 52, such as screws, arranged circumferentially near the upper 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 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 FIG. 8(b). The fluid in the insertion device 8 is then drained, and the retention member 83 and the insertion shaft 82 are released from the fixation through an access hole (not shown). The insertion device 8 is then removed from the operating valve 6, and the operating valve 6 is then 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 switching valve device 1 consisting of the housing 5 and the valve element 9 functions as a valve element.

[0033] As shown in Figure 9, the above-mentioned valve element 9 is formed in a roughly cylindrical shape when viewed from above, and has ports 9A, 9B, 9C, and 9D formed in a roughly cross-shaped manner on its side walls, with these ports 9A to 9D connected internally.The main components of the valve element 9 are an inner valve box 91 (valve box) in which these ports 9A to 9D are connected internally, valve shafts 93a and 93b installed 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 regulating member 95 for regulating 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 hermetically enclose each of the ports 9A to 9D, allowing 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, a substantially central region 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 the ports 9A, 9B, 9C, and 9D of the inner valve case 91 communicate with the 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., toward the opening 5D of the housing 5 (see FIG. 2).

[0034] 11(a) to 11(c), by attaching the operating part 94 to the valve stem 93a, the valve stem 93a is surrounded by a cylindrical part 94a and a restricting member 95. The outer peripheral surface of the valve stem 93a is covered by a cover member 96, and by operating the operating part 94, the valve stem 93a and the cover member 96 rotate integrally within the cylindrical part 94a. In addition, the cross-sectional shape of the cover member 96 is such that a portion of the circumferential surface protrudes due to its protrusion 96a, i.e., the cross-sectional shape is an eccentric, approximately elliptical shape.

[0035] 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 a recess 95c is formed in the approximate center on the valve stem 93a side, recessed toward the outer diameter side of the tubular portion 51a. The restricting member 95 has screws 95a and 95b as adjustment portions 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 penetrate 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.

[0036] For example, when the operating unit 94 is operated from the state shown in Fig. 11(b) as shown in Fig. 11(a) to turn the protruding portion 96a of the cover member 96 attached to the valve shaft 93a to the left, the arc-shaped portion 92a of the valve element 92, which is formed in a generally fan shape, turns 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-shaped portion 92a of the valve element 92 are located at the same position in the circumferential direction. 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.

[0037] 11(c) from the state shown in FIG. 11(b), when the operating part 94 is operated to turn the valve shaft 93a to the right, the arc part 92a of the valve body 92 turns to the right along with the valve shaft 93a, as shown in FIG. 10(c). The inner valve box 91 is formed with side wall steps 91a-91d that stand upright from the bottom to the top. The side wall steps 91a-91d may also protrude toward the valve shaft 93. As shown in FIG. 9, sealing members 53a-53d that seal the inner surface of the housing 5 are disposed vertically on the outer surfaces of the side wall steps 91a-91d, respectively. 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 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 member 59 and the sealing members 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, sealing the valve body 92, thereby 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, sealing the valve body 92, thereby closing the port 9A. At this time, the other side portion 96R of the protruding portion 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 (c), and as a result, as shown in Figures 10(a) to (c), the movement of the arc portion 92a of the valve body 92 from the ports 9A and 9C toward the port 9B is restricted, and it is not possible to rotate it toward the vicinity of port 9B.That is, port 9B is a specific port according to the present invention.

[0038] 11(a) to 11(c), a restricting member 95 is fixed to a portion of the circumference of the tubular portion 94a of the valve element 92, so that the valve element 92 has a rotation range of approximately 180 degrees in the clockwise direction from port 9C to port 9A, or in the counterclockwise direction from port 9A to port 9C. Furthermore, the valve element 92 has a fan shape that extends over approximately 90 degrees when viewed from above, so that it is possible to close a region of approximately 270 degrees between the side wall step portions 91a and 91b.

[0039] Furthermore, a recess 95c is formed in the restricting member 95, which allows the rear end 96b of the arc-shaped cover member 96 to rotate smoothly without being hindered. After the valve shaft 93 has been rotated to a desired position, the tip of a fixing screw 94b, which can advance and retreat from the outer diameter side to the inner diameter side of the cylindrical portion 94a, is pressed against flat portions H formed on each of the four sides of the cover member 96, thereby fixing the position of the valve body 92.

[0040] 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. When laying the new pipe 20, it is advisable to perform pipe cleaning. 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 according to the above-mentioned pipe cleaning procedure. The timing of pipe cleaning is not limited to this.

[0041] With the arc portion 92a of the valve body 92 closing 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) of 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, a fluid is supplied via a supply port (not shown) of the new pipe 20. Once satisfactory test results are confirmed in the pressure test, the gate valve 58a of the bypass pipe 58 connecting the opening 5A and the opening 5D is switched to an 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. As a result, the new pipe 20 is filled with fluid, and the fluid pressure in the new pipe 20 and the fluid pressure in 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. Also, since the fluid in 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 opening and closing the valve element 92. The timing of the pressure resistance test is not limited to this.

[0042] Next, one end of the new pipe 22 is connected to the valve 4 disposed 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, pipe cleaning and a pressure test are also performed on the new pipe 22. Thereafter, the valve 4 is switched to an open state, and fluid may be allowed to flow into the new pipe 22 while performing air bleeding, or an inflow may be performed as described below.

[0043] Next, the process moves to a step in which the working valve 6 is attached to the housing 3 installed at point Y of the existing pipe 14b in the same manner as described above, and the existing pipe 14b is cut using the pipe cutting device 7. Note that since 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 divided into existing pipe 14b', which is connected at one end to opening 5C of housing 5 and to opening 3A of housing 3, and existing pipe 14c, which is connected to opening 3C of housing 3 and to a branch pipe (not shown) downstream (see Figure 2). Furthermore, the flow is maintained uninterrupted during this cutting process.

[0044] After the step of cutting 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 through existing pipes 12, 13, and 14a flows into housing 5 and branches into existing pipe 14b' via opening 5C and into new pipe 21 via opening 5B. The branched fluids join together in housing 3 installed at point Y and flow downstream through existing pipe 14c.

[0045] Next, the process moves to installing the partition member 30 in the housing 3 using the insertion device 8. The installation of the partition member 30 is the same procedure as the installation of the valve member 9 described above, so a detailed explanation will be omitted. The partition member 30 installed in the housing 3 comprises a partition body 31 that connects opening 3B with opening 3C of openings 3A to 3C of the housing 3 and blocks opening 3A, and 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, the fluid that flows in from opening 3B flows smoothly out toward opening 3C. The rear side of partition 31 is a closed area that closes the opening, and by positioning partition 31 on the front side leaving the opening areas of openings 3B and 3C, the rear side of partition 31 closes opening 3A of housing 3 and releases the communication state downstream of opening 5C of housing 5 at point Z (see FIG. 2). Note that partition member 30 may also be a switching valve.

[0046] Next, as shown in Figure 3, the operating portion 94 of the valve member 9 is operated to rotate the valve body 92 toward the opening 5C, thereby blocking the inflow of fluid into the existing pipe 14b'. By rotating the valve body 92 toward the opening 5C, the fluid from tank A passes through the new pipe 20, the opening 5D of the housing 5, and the opening 5B, and then passes through the new pipes 21 and 22, the openings 3B and 3C of the housing 3, and the existing pipe 14c, and is then allowed to flow downstream. Note that the fluid from tanks A to C also flows into the housing 5 through the existing pipes 12, 13, and 14a, and the opening 5A.

[0047] 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 the two ports (α<β). The ports 9A and 9C with the larger opening angle are connected to the existing pipe 14, and the ports 9B and 9D with the smaller opening angle are connected to the new pipes 20 and 21. This minimizes the influence 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 element 92 from port 9D to port 9C or when 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 action of a force pressing 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, flow velocity effects, etc. 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. Note that 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.

[0048] Returning to FIG. 2, fluid is stagnating in the existing pipe 14b'. First, the fluid is discharged from a discharge port (not shown) installed in the existing pipe 14b'. After the fluid is discharged, 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 FIG. 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 inner valve box 91 approximately equal, facilitating the rotation of 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 may be plugged.

[0049] Next, to replace the existing pipes 10-13, 14a shown in Fig. 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 Figs. 11(a) to (c) to restrict counterclockwise rotation, so that the arc portion 92a of the valve element 92 passes through port 9D as shown in Fig. 10(b), and the operating part 94 is further operated to cause the arc portion 92a of the valve element 92 to close port 9A as shown in Fig. 10(c). As a result, the restricting member 95 prevents the arc portion 92a of the valve body 92 from blocking port 9B, which is connected to the opening 5B, and prevents passage over port 9B, thereby preventing a flow interruption caused by accidental blocking.In this case, the valve body 92 temporarily crosses port 9D, but since there is inflow from the existing pipe 14a side, an uninterrupted flow state can be maintained.

[0050] As described above, by rotating valve element 92 from opening 5C toward 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 state. As shown in FIG. 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.

[0051] 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 is composed 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 in 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 inner valve box 91 approximately equal, making valve element 92 easier to rotate.

[0052] Finally, as shown in the area enclosed by the dashed-dotted line 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 side of opening 5A that was previously closed, and fluid supplied from tanks A to C on the upstream side flows in through openings 5A and 5D of the casing 5, and fluid flows out downstream from 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.

[0053] 12(a) and 12(b) show a switching valve device 100 equipped with a switching valve 190. Instead of the restricting member 95 of the previous embodiment, stopper members 40, 41, which are restricting members in this case and are formed in a roughly T-shape in top view at two locations on the bottom surface 50a of the inner valve box 105, are disposed. 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 of the inner valve box 105 in FIG. 12(a), thereby restricting rotation toward port 9B in the same way as the restricting member 95 described above.

[0054] The stopper members 40, 41 are generally T-shaped when viewed from above, and are erected approximately vertically upward from a bottom surface fixed to the bottom surface 50a of the inner valve box 105, and are each 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) to rotate the valve element 192, 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 the rotation toward port 9B.

[0055] As described above, the switching valve device 1 comprises a housing 5 with a split structure in which openings 5A to 5D for connecting fluid pipes are formed and which fits tightly onto an existing pipe, and a switching valve 9 which is installed tightly in a sealed manner at a cut section of the existing pipe inside the housing 5, and which can connect a new pipe to the housing 5 in an uninterrupted flow state. The housing 5 has openings 5A to 5D formed in a roughly cross direction, and the switching valve 9 has an inner valve box 91 in which ports 9A to 9D which communicate with the openings 5A to 5D, respectively, are formed in a roughly cross direction, and a valve body 92 which can selectively close one port. By closing one of the ports 9A to 9D formed in a roughly cross direction with the valve body 92, an uninterrupted flow state is maintained through the remaining three ports which are open, and the existing pipe connected to the opening side which communicates with the port whose valve body 92 is closed can be removed and a new fluid pipe can be laid in sequence, so that multiple fluid pipes can be updated and the construction is highly scalable.

[0056] The inner valve box 91 is provided with a regulating member 95 that prevents the valve body 92 from blocking a specific port 9B among the ports 9A to 9D.The regulating member 95 allows the specific port 9B to be kept open at all times, so that the fluid pipe connected to the opening 5B that communicates with this port 9B can always be maintained in an uninterrupted flow state, and a flow interruption due to accidental blockage can be prevented.

[0057] Furthermore, the valve element 92 is rotatably arranged around a rotation axis provided 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 regulating member 95, thereby blocking ports 9A, 9B, and 9D except for the specific port 9B. Since the valve element 92 is restricted from passing through the specific port 9B by the regulating member 95, a temporary flow interruption state that occurs when the valve element 95 passes can be prevented.

[0058] Furthermore, among the ports formed in an approximately cross-shaped configuration, the opening angle α formed in a plan view by the sealing members 53b, 53c and 53d, 53a that seal a pair of opposing ports 9B, 9D is smaller than the opening angle β formed by the sealing members 53a, 53b and 53c, 53d that seal the remaining pair of ports 9A, 9C that are approximately perpendicular to the pair of ports (α<β), and therefore the influence of the fluid in the fluid pipes connected to the openings 5B, 5D that communicate with the ports 9B, 9D on the side with the smaller opening angle can be kept small.

[0059] This is a pipe laying method for laying a new fluid pipe in an uninterrupted flow state using a switching valve device 1, and includes 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, one of openings 5A to 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 body 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 formed in an approximately cross direction with the valve body 92, an uninterrupted flow state is maintained through the remaining three ports that are open, and the existing pipe connected to the opening communicating with the port whose valve body 92 is closed can be removed or a new pipe can be laid sequentially, so multiple fluid pipes can be updated and the construction is highly scalable.

[0060] Furthermore, new pipes 20, 25 are connected to the openings 5A to 5D of the housing 5 as new upstream fluid pipes, and new pipe 21 is connected to the new downstream fluid pipe, so that new flow paths can be secured by the new pipes 20, 21, 25 regardless of whether or not the existing fluid pipe 14 fitted onto the housing 5 is removed.

[0061] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0062] 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, and some steps may be omitted or changed as long as the replacement with a new pipe can be performed while maintaining an uninterrupted flow state, and the switching valve device of the present invention can be applied to various facilities in which existing pipelines are configured, not limited to water purification facilities.

[0063] In the above embodiment, the restricting member 95 and the stopper members 40, 41 are used to restrict the valve body 92 from closing the port 9B, but this is not limiting, and as long as replacement with a new pipe is performed while maintaining an uninterrupted flow state, the closing of other ports may be restricted.

[0064] In addition, in the above embodiment, the upstream side and downstream side are connected to the newly installed pipe, but for example, both upstream sides may be connected to the newly installed pipe, or both downstream sides may be connected to the newly installed pipe. [Explanation of symbols]

[0065] 1. Switching valve device 3. Housing 3A~3C opening 4 valves 5. Cabinet 5A~5D opening 6 Working valve 7 Tube cutting device 8 Insertion Device 9 Valve element (switching valve) Ports 9A~9D 9B Specific Port 10~14 Existing pipes 20~25 New pipes 30 Partition member 31 Partition 40 Stopper member (regulating member) 41 Stopper member (regulating member) 53a to 53d sealing members 91 Inner box (bento box) 92 Valve body 92a Arc section 93a, 93b Valve stem 94 Operation section 95 Regulatory components 96 Cover member

Claims

1. 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 to be connected to existing fluid pipes and a first opening to be connected to a new fluid pipe, The switching valve comprises a valve body in which a pair of ports communicating with the pair of openings, respectively, facing each other and a port communicating with the first opening, are formed; a valve element capable of selectively closing one of the ports; and a valve stem provided in the valve body and movably supporting the valve element, a switching valve device characterized in that an opening angle formed by a sealing member that seals the pair of ports among the ports is larger than an opening angle formed by a sealing member that seals the port that communicates with the first opening.

2. 2. The switching valve device according to claim 1, wherein the pair of openings and the first opening are substantially perpendicular to each other and have substantially the same opening width.

3. the pair of openings, the first opening, and a second opening facing the first opening are formed in a substantially cross direction in the housing; 3. The switching valve device according to claim 1, wherein the valve body of the switching valve has the pair of ports, the port communicating with the first opening, and the port communicating with the second opening, which are formed in a substantially cross-shaped configuration.

4. 4. The switching valve device according to claim 1, wherein the valve body has a side wall step portion supporting the valve element that selectively closes one of the ports, and the sealing member is provided on an outer surface of the side wall step portion.

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