JP2024048972A - Uninterrupted flow method - Google Patents

Abstract

[Problem] To provide a method for uninterrupted flow that can maintain smooth movement and sealing of the valve element of an operating valve. [Solution] An operating valve 5 capable of opening and closing an upper opening 10C of a housing 10 is installed above the housing 10, which is hermetically attached to an existing fluid pipe 2, and at least one of the following operations is performed in an uninterrupted flow state: installation of a butterfly valve 14 inside the housing 10 (flow control installation process), removal (flow control removal process), and cutting of the existing fluid pipe 2 (removal process), and in each operation process, the load of the valve cover 5b is supported by jacks 104, 104 placed on the ground or foundation. [Selected Figure] Figure 6

Description

The present invention relates to a method for performing at least one of the following operations without interrupting flow: attaching or removing a flow control device to an existing flow path, or cutting an existing fluid pipe.

The installation of flow control devices such as valves and plugs in existing flow paths through which water, gas, etc. flows, the removal and reinstallation of flow control devices installed in existing flow paths for the purpose of repairing or maintaining breakdowns caused by deterioration over time, and the replacement of part of an existing fluid pipe with a new fluid pipe due to deterioration over time or the connection to another flow path may be performed without interrupting the flow.

As a method for performing this type of work without interrupting the flow, for example, a method is known in which a housing is attached to the fluid pipe in a sealed manner, a working valve that can open and close the inside of the housing is attached to the upper opening of the housing, a cutting machine having a cutter and a drive unit is installed on the working valve, and with the working valve open, the cutter is inserted by the drive unit to cut part of the fluid pipe inside the housing without interrupting the flow.

As a method for installing a fluid control valve at a location where a fluid pipe has been cut using the above-mentioned method, for example, a method is available in which a working valve is attached to the top of a housing, an insertion machine is attached to the top of the working valve, and the fluid control valve is introduced into the housing using the insertion machine while the working valve opens the top opening of the housing, thereby installing a fluid control valve in an uninterrupted state inside the housing. One working valve used in this uninterrupted flow method is mainly composed of a valve box attached to the top of the housing, a valve cover protruding laterally from the valve box, and a valve body that can move between the valve box and the valve cover, and is designed so that the top opening of the housing can be opened by moving the valve body from the valve box to the valve cover (see, for example, Patent Document 1).

JP 2019-74122 A (pages 11 to 14, figures 12 to 22)

In the uninterrupted flow method described in Patent Document 1, when the working valve is attached to the top of the housing, the valve box is placed in the housing directly below, but the valve cover is attached in a cantilevered state so that it protrudes to the side from the valve box. This causes an unbalanced load to be placed on the valve cover and the valve body that move back and forth sideways inside the valve box, preventing them from moving smoothly. In addition, the bolts and nuts that fasten the valve box and valve cover are loaded, causing the sealing material between the valve box and the valve body to rub, reducing the sealing performance.

The present invention was made with a focus on these problems, and aims to provide a method of construction without interrupting flow that can maintain smooth movement and sealing of the valve body of the working valve.

In order to solve the above problems, the flow-uninterrupted construction method of the present invention is as follows:
A method for uninterrupted flow in which a valve capable of opening and closing an upper opening of a housing is installed above a housing that is hermetically attached to an existing fluid pipe, and at least one of the following operations is performed without interrupting flow: installation and removal of a flow regulator in the housing, and cutting of the existing fluid pipe;
The working valve is adapted to open and close an upper opening of the housing by moving a valve body between a valve box attached to the upper part of the housing and a valve cover protruding laterally from the valve box,
During the above operation, the load of the valve cover is supported by a support means placed on the ground or foundation.
According to this feature, the load of the valve cover protruding laterally from the valve box is supported on solid ground or foundation via the support means, thereby preventing the application of an unbalanced load to the valve body, thereby maintaining smooth movement and sealing performance of the valve body of the operating valve.

The support means is characterized by including a height adjustable jack.
According to this feature, support can be adjusted according to the height from the ground or foundation to the valve cover.

The load of the valve cover is supported by a plurality of the jacks.
According to this feature, the height of the valve cover at multiple points can be adjusted individually, so that the valve cover can be maintained approximately horizontal.

The valve cover protrudes from the valve body in a pipe axis direction of the existing fluid pipe,
The supporting means is characterized in that it is disposed on both sides of the existing fluid pipe.
According to this feature, both sides in the width direction of the valve cover can be stably supported while avoiding the fluid pipe.

The ground is characterized by being the ground surrounding a hole excavated for mounting the housing.
This feature allows the support means to be easily placed without having to enter the borehole.

1A is a plan view showing the state in which the area around a specific portion of a fluid pipe is excavated and the lower housing is placed on the concrete base in the uninterrupted flow construction method of the embodiment, and FIG. 1B is a front view showing the state with a part cut away. 1A is a plan view showing a state in which an upper housing is temporarily fixed to a lower housing, and FIG. 2A is an enlarged cross-sectional view of a portion X in FIG. 2B, and FIG. 2B is a side view, partly cut away, showing a state in which an upper housing is temporarily fixed to a lower housing. FIG. 4 is a partially cutaway front view showing a state in which the working valve is attached to the housing. 1A is a schematic cross-sectional view showing a state before the underside of the valve cover is supported by a jack, and FIG. 1A is a plan view showing a state in which an operating valve is attached to a housing, and FIG. FIG. 2 is a side view, partially cut away, showing the operating valve attached to the housing. 11 is a partially cutaway front view showing a state in which a portion of a fluid pipe has been cut off using a cutting device. FIG. FIG. 2 is a side view, partially cut away, showing the state at the start of inserting the butterfly valve using the insertion device. FIG. 2 is a partially cutaway front view showing the butterfly valve after installation. 1A is a partially cutaway front view showing a working valve attached to a housing in a flow-uninterrupted construction method according to a first modified example of the present invention, and FIG. 1B is a partially cutaway side view showing the working valve attached to a housing in a flow-uninterrupted construction method according to a first modified example of the present invention. 1A is a partially cutaway front view showing an operating valve attached to a housing in a flow-uninterrupted construction method according to a second modified example of the present invention, and FIG. 1B is a partially cutaway side view showing the same. 13 is a partially cutaway front view showing a state in which a portion of a fluid pipe has been cut off using a cutting device in a flow-uninterrupted construction method as variant example 3 of the present invention. FIG. FIG. 11 is a side view, partially cut away, showing the state at the start of butterfly valve insertion using an insertion device in the uninterrupted flow method as modified example 3 of the present invention. 13 is a partially cutaway front view showing a state in which a portion of a fluid pipe has been cut off using a cutting device in a flow-uninterrupted construction method as variant example 4 of the present invention. FIG. FIG. 11 is a side view, partially cut away, showing the state at the start of butterfly valve insertion using an insertion device in the uninterrupted flow method as modified example 4 of the present invention.

The following describes the implementation of the flow-uninterrupted construction method according to the present invention based on examples.

As an example of a method for preventing flow interruption, a method for installing a butterfly valve 14 as a flow control device in an existing flow path will be described with reference to Figures 1 to 10.

As the uninterrupted flow method of this embodiment, a series of steps will be described, from cutting out a predetermined portion of the fluid pipe 2 that constitutes an existing flow path buried underground within the housing 10, to installing a butterfly valve 14 at the cut-out portion. Note that the fluid in the fluid pipe is clean water in this embodiment, but is not limited to this, and may be, for example, industrial water, agricultural water, sewage, gas, or a gas-liquid mixture of gas and liquid.

The fluid pipe 2 according to the present invention is a ductile cast iron pipe, and is formed in a generally cylindrical shape in cross section. The fluid pipe according to the present invention may be made of other metals such as cast iron or steel, or may be made of concrete, polyvinyl chloride, polyethylene, polyolefin, etc. Furthermore, the inner circumferential surface of the fluid pipe may be covered with an epoxy resin layer, mortar, plating, etc., or the inner circumferential surface of the fluid pipe may be covered with an appropriate material by powder coating.

First, a preparation process is carried out to prepare the work site. Referring to Figures 1(a) and (b), in the preparation process, a drilling hole 16 is formed by excavating the ground around a predetermined portion of the fluid pipe 2 buried underground, that is, the portion where the butterfly valve 14 as a fluid control is to be installed.

Next, concrete base F is poured into the bottom of the excavated hole 16, i.e., the excavated ground G, to form part of the foundation that transmits the load from the fluid pipe 2 and the housing 10 to the ground G. The top surface Fa (see FIG. 4) of the concrete base F is spaced vertically from the exposed bottom of the fluid pipe 2. Note that instead of concrete base F, a steel sheet or the like may be used as the foundation as long as it can support the load of the lower housing 30 of the housing 10 and the jack 4 described below.

Next, the lower housing placement process is performed to place the lower housing 30. In the lower housing placement process, the lower housing 30 is suspended by a hoisting tool H equipped with a hook and wire W suspended by a crane (not shown) and fitted onto the lower part of the fluid pipe 2, and two jacks 4, 4 (see FIG. 3(b)) with load support and height adjustment functions are placed between the lower housing 30 and the concrete base F. The lower housing placement process will be described in detail below.

The lower housing 30 is formed in a T-shape when viewed from the front, with a body 31 extending downward and formed in a cylindrical shape with a bottom, and curved plate-like half-split arms 32, 33 extending laterally and generally perpendicular to the body 31, and curved in a semicircular arc when viewed in the axial direction of the fluid pipe 2. In addition, a drain pipe 35 to which a drain pipe (not shown) is connected is provided at the bottom of the body 31 in an openable and closable manner, so that water inside the housing 10 can be discharged to the outside of the housing 10.

The jack 4 is a so-called mechanical jack in which a bolt 4b is screwed into a female thread formed on a bottomed cylindrical base 4a having a pedestal. Note that instead of a mechanical jack, a liquid-operated or air-operated jack may also be used, and the type is not limited to the above.

A flat disk-shaped dish 4c is placed on the upper end of the bolt 4b. When placing the jacks 4, 4 on the concrete base F, the jacks 4, 4 are positioned at a position spaced apart on the outer diameter side and in a direction perpendicular to the pipe axis with respect to the center of the bottom wall 31a of the body 31 (see FIG. 3(b)).

In detail, when fitting the lower housing 30 to the fluid pipe 2, the lower housing 30, which is suspended by a crane, is fitted to the bottom of the fluid pipe 2 and lifted up so that the inner circumferential surface of the lower housing 30 abuts against the outer circumferential surface 2a of the fluid pipe 2. At this time, a rubber sheet or the like may be sandwiched between the inner circumferential surface of the lower housing 30 and the outer circumferential surface 2a of the fluid pipe 2 to prevent scratches. Then, the length of the jacks 4, 4 is adjusted according to the distance between the bottom wall 31a of the lower housing 30 and the concrete base F, and the jacks 4, 4 are placed between the bottom wall 31a and the concrete base F.

This keeps the inner circumferential surface of the lower housing 30 in contact with the outer circumferential surface 2a of the fluid pipe 2; in other words, the lower housing 30 is held vertically and stably by the fluid pipe 2 and the jacks 4, 4, so that the sling H and wire W can be removed from the lower housing 30.

Next, a connecting process is performed to hermetically connect the upper housing 20 of the housing 10 to the lower housing 30. As shown in Figures 2(a) and (b), in the connecting process, first, the upper housing 20 is suspended by a crane using a hoist H and a wire W, and the upper housing 20 is fitted onto the fluid pipe 2, and the cut surface 20a of the upper housing 20 is placed against the cut surface 30a of the lower housing 30.

The upper housing 20 is formed in an inverted T-shape when viewed from the front, with a neck 21 that extends upward and is formed in a substantially cylindrical shape, and half-split arms 22, 23 that extend laterally and are formed in a semicircular curved plate shape when viewed in the axial direction of the fluid pipe 2. An upper opening 10C is formed at the upper end of the neck 21. In addition, holes 71, which will be described later, are formed in two places on the peripheral surface of the neck 21.

Furthermore, the half-split arms 22, 23 of the upper housing 20 and the half-split arms 32, 33 of the lower housing 30 are formed with rectangular plate-shaped flanges (not shown) that are approximately parallel to the respective split surfaces 20a, 30a and protrude outward, and the upper housing 20 and the lower housing 30 can be temporarily fixed together by fastening these flanges with bolts and nuts (not shown).

Then, the split surfaces 20a, 30a of the upper and lower housings 20, 30 are hermetically welded together to form the housing 10. As a result, the half arms 22, 32 form the cylindrical arm 10A of the housing 10, and the half arms 23, 33 form the cylindrical arm 10B of the housing 10.

In addition, multiple adjustment bolts (not shown) that can be moved radially are provided at appropriate locations on the half-split arms of the upper housing 20 and the lower housing 30, and by moving these adjustment bolts back and forth as appropriate, the upper housing 20, the lower housing 30, or the housing 10 after welding them together can be radially adjusted relative to the fluid pipe 2.

Next, a sealing process is performed to seal the gap between the housing 10 and the fluid pipe 2. As shown in FIG. 3(a), in the sealing process, the seal ring 12 is first arranged around the outer circumferential surface 2a of the fluid pipe 2, and the half-shaped pressure rings 13 are fitted onto the fluid pipe 2 and connected, and the flange of the arm 10B and the pressure ring 13 are fastened by screwing the nut N2 onto the T-head bolt B2.

At this time, since the center of the arm 10B is aligned with the pipe axis of the fluid pipe 2, an annular gap of approximately constant width is formed in the circumferential direction between the inner peripheral surface of the arm 10B and the outer peripheral surface 2a of the fluid pipe 2. This not only makes it easier to press the seal ring 12 axially between the arm 10B and the fluid pipe 2, but also allows the pressed-in seal ring 12 to be pressed against the inner peripheral surface of the arm 10B and the outer peripheral surface 2a of the fluid pipe 2 with a uniform force in the circumferential direction to form a seal.

Furthermore, the bolts 13A, 13A, ... evenly spaced in the circumferential direction are used to press the claw member 13B arranged on the inner diameter side of the pressure ring 13 against the outer circumferential surface 2a of the fluid pipe 2. Note that the explanation of the arm 10A side is the same as that of the arm 10B side, so the explanation is omitted.

As described above, when fitting the housing 10 onto the fluid pipe 2, the housing 10 can be positioned by using the jacks 4, 4 while ensuring sufficient movement relative to the fluid pipe 2. This allows the housing 10 to be reliably aligned with the fluid pipe 2, simplifying construction.

In addition, during the lower housing installation process, the lower housing 30 can be clamped between the fluid pipe 2 and the jacks 4, 4, so the same crane can be used to transport the upper housing 20 and suspend the housing 10.

Next, although not shown directly in the figures, a flange lid for a water pressure test is attached to the flange portion 21a of the housing 10, and a test is performed by applying water pressure approximately equal to that inside the fluid pipe 2 to the sealed gap between the inner circumferential surface of the housing 10 and the outer circumferential surface 2a of the fluid pipe 2. At this time, water fills the housing 10, increasing its total weight, but because the housing 10 is supported by the jacks 4, 4, it is possible to prevent most of the total weight of the housing 10 from acting directly on the fluid pipe 2. This makes it possible to prevent the fluid pipe 2 from bending before it is cut.

In addition, although the fluid pipe 2 is axially inserted through the housing 10, the jacks 4, 4 are positioned in a plane view away from the axis of the fluid pipe 2 toward the outer diameter and perpendicular to the axis, preventing the housing 10 from rotating around the axis of the fluid pipe 2.

After the hydraulic test is completed, the flange lid is removed and a pouring process is performed in which protective concrete C1 is poured between the fluid pipe 2 and the housing 10 and the concrete base F. As shown in FIG. 4, in the pouring process, the protective concrete C1 shown in a dot pattern is poured so as to integrate the arm 10A, the exposed portion of the fluid pipe 2 on the arm 10A side, and the concrete base F. The same is true for the arm 10B and the exposed portion of the fluid pipe 2 on the arm 10B side. In this pouring process, the jacks 4, 4 mentioned above support the load of the housing 10 etc. from below, so that the position of the housing 10 can be maintained until the protective concrete C1 hardens.

In this way, the protective concrete C1 is formed integrally with the upper surface Fa of the base concrete F so as to cover the lower housing 30 and the lower half of the fluid pipe 2 from below, and approximately horizontal upper surfaces C1b, C1b extending in the pipe axial direction are formed in front of and behind the fluid pipe 2 (see Figures 6(a) and (b)). This protective concrete C1 constitutes part of the foundation that transmits the force from the fluid pipe 2 and housing 10 to the ground G.

Next, a cutting process is performed to cut out the fluid pipe 2. As shown in FIG. 4, in the cutting process, first, jacks 104, 104 serving as support means for supporting the load of the valve cover 5b (described later) with the base concrete F are placed on the top surface Fa at opposing positions that sandwich the fluid pipe 2 radially, so as not to come into contact with the fluid pipe 2 and the right side surface C1a of the protective concrete C1.

As shown in Figures 5(a) and (b), the jacks 104, 104 are so-called mechanical jacks in which a bolt 104b is screwed into a female thread formed in a bottomed cylindrical base 104a having a pedestal. A flat disk-shaped dish 104c is placed on the upper end 104d of the bolt 104b. The jacks 4, 4 are constructed in the same way as the jacks 104, 104, except for their height.

The upper end 104d of the bolt 104b is formed in a cone shape. A recess 104e that is cone-shaped in cross section is formed at the radial center of the lower surface of the dish 104c. The upper end 104d of the bolt 104b and the recess 104e of the dish 104c are formed to be able to fit together. This makes the dish 104c detachable from the bolt 104b and prevents it from rotating with the rotation of the bolt 104b. In addition, positioning of the dish 104c on the bolt 104b is easy. It is preferable to make the cone angle of the recess 104e of the dish 104c gentler than the cone angle of the upper end 104d of the bolt 104b, and by doing so, the dish 104c can be slightly inclined with respect to the bolt 104b.

Place the jacks 104, 104 in a position where the lower surface 5i of the valve cover 5b does not come into contact with the upper surface Fa of the base concrete F (see Figure 5 (a)).

Next, the working valve 5 is attached to the top of the upper housing 20. In detail, as shown in FIG. 4, the working valve 5 is located above the housing 10 and has a valve box 5a with a through passage 5d penetrating in the vertical direction, a valve cover 5b connected laterally to the valve box 5a, and a valve body 5c movably provided between the valve box 5a and the valve cover 5b and provided with a seal member (not shown) on the circumferential surface. In addition, flanges 5e and 5f protruding in the outer diameter direction are provided at the upper and lower parts of the through passage 5d of the valve box 5a. At the side end of the valve cover 5b, the end of a valve stem 5g that is screwed with the valve body 5c inside the valve cover 5b protrudes, and a drive part 5h is provided to apply a rotational drive force to the valve stem 5g.

Next, as shown in Figures 6(a), (b) and 7, the working valve 5 is lowered by a crane, and the valve box 5a is placed on the upper opening 10C of the upper housing 20. The flange portion 21a of the upper housing 20 and the flange portion 5e of the valve box 5a are fastened with bolts and nuts (not shown). Note that a gasket (not shown) is interposed between the flange portion 21a of the upper housing 20 and the flange portion 5e of the valve box 5a, so that the upper housing 20 and the valve box 5a are connected in a sealed state.

When the valve box 5a of the working valve 5 is attached to the upper housing 20, the valve cover 5b protrudes laterally (horizontally) from the valve box 5a. In more detail, the valve body 5c of the working valve 5, which can open and close the upper opening 10C of the housing 10, is arranged to be horizontally movable in the pipe axis direction of the fluid pipe 2 between a closed position (inside the valve box 5a) where the upper opening 10C can be closed and a retracted position (inside the valve cover 5b) where the valve body retracts laterally from the closed position, so that the valve cover 5b protrudes laterally from the valve box 5a.

After fastening the valve box 5a and the upper housing 20 with bolts and nuts (not shown), as shown in FIG. 5(b), the bolts 104b of the front and rear jacks 104, 104 are rotated to raise the plate 104c until it abuts against the lower surface 5i of the valve cover 5b, adjusting the height. Then, the crane is released from the suspension, and the lower surface 5i of the valve cover 5b abuts against the plate 104c, and the weight of the valve cover 5b is supported by the upper surface Fa of the concrete base F via the front and rear jacks 104, 104.

More specifically, as shown in Figures 6(a), (b) and 7, the jacks 104, 104 are arranged on the tip side of the underside 5i of the valve cover 5b and on the front and rear sides of the fluid pipe 2, and the valve cover 5b is supported from below at two points, the front and rear, on the tip side, preventing tilt not only in the left-right direction, which is the direction of movement of the valve body 5c, but also in the front-rear direction, which is perpendicular to the direction of movement of the valve body 5c. More specifically, the valve cover 5b is supported on the left side by the valve box 5a, and the front and rear positions on the right side are supported by the jacks 104, 104, so that it is maintained approximately horizontal.

This prevents the valve cover 5b from bending due to the load, making it difficult for an unbalanced load to be applied to the valve body 5c inside the valve cover 5b. In addition, even if the top surface Fa is uneven, the height can be adjusted using the front and rear jacks 104, 104, so that by slightly changing the height of the front jack 104 relative to the rear jack 104, for example, the valve cover 5b can be easily supported approximately horizontally without applying an unbalanced load in the torsional direction. When adjusting the height of the front and rear jacks 104, 104, it is preferable to place a spirit level on the top surface of the tip side of the valve cover 5b to check the horizontal state.

In this embodiment, the working valve 5 is illustrated as being hung down with the valve box 5a, valve lid 5b, and valve body 5c integrated and attached to the upper housing 20, but the present invention is not limited to this. After only the valve box 5a is attached to the upper opening 10C of the upper housing 20, the valve lid 5b and valve body 5c are hung integrally from the valve box 5a, or the valve body 5c is attached first and then the valve lid 5b, in that order, to assemble the working valve 5 above the upper housing 20.

In addition, in this embodiment, the valve box 5a and the upper housing 20 are fastened together with bolts and nuts (not shown), and then the height of each of the front and rear jacks 104, 104 is adjusted. However, the present invention is not limited to this. The valve box 5a may be placed above the upper housing 20, and the valve cover 5b may be placed on the plates 104c of the jacks 104, 104, and then the valve box 5a and the upper housing 20 may be fastened together with bolts and nuts (not shown).

Next, as shown in Figure 8, the flange portion 5f of the valve box 5a is connected to the lower flange portion 6a of the mounting flange cylinder 6 with bolts and nuts (not shown), and the upper flange portion 6b of the mounting flange cylinder 6 is connected to the drive mechanism 7 with bolts and nuts (not shown). Note that gaskets are interposed between the flange portion 5f of the valve box 5a and the lower flange portion 6a of the mounting flange cylinder 6, and between the upper flange portion 6b of the mounting flange cylinder 6 and the drive mechanism 7, so that the valve box 5a, the mounting flange cylinder 6, and the drive mechanism 7 are connected in a sealed state.

A cutter consisting of a hole saw 8a and a center drill 8b is arranged inside the mounting flange tube 6, and the hole saw 8a and the center drill 8b are rotated by the drive mechanism 7 and raised and lowered so that they can advance and retreat within the housing 10. In this way, the mounting flange tube 6, the hole saw 8a and the center drill 8b, and the drive mechanism 7 that drives them to raise and lower constitute the cutting device 8.

In this way, even if the weight of the working valve 5, the mounting flange tube 6, and the drive mechanism 7 are added and the total weight of the housing 10 increases, the housing 10 is supported by the jacks 4, 4 and the protective concrete C1, so it is possible to prevent most of the total weight of the housing 10 from acting directly on the fluid pipe 2. Therefore, it is possible to prevent the fluid pipe 2 from bending before it is cut.

In addition, the jacks 4, 4 and protective concrete C1 prevent the housing 10 from rotating around the axis of the fluid pipe 2, so there is no risk of the working valve 5, mounting flange tube 6, and drive mechanism 7, which are integrally erected above the housing 10 and have a high center of gravity, tipping over.

In addition, the arm 10A and exposed portion of the fluid pipe 2 on the arm 10A side are supported by the protective concrete C1 and integrated with the concrete base F, and the arm 10B and exposed portion of the fluid pipe 2 on the arm 10B side are supported by the protective concrete C1 and integrated with the concrete base F, preventing most of the total weight of the housing 10 from acting on the fluid pipe 2. This prevents the fluid pipe 2 from bending before it is cut.

Then, the valve body 5c of the working valve 5 is moved back from the valve box 5a to the valve cover 5b to open the valve, and a portion of the fluid pipe 2 is cut off with the cutting device 8 in an uninterrupted state. This allows the fluid in the pipe to flow into the inside of the housing 10.

At this time, the valve body 5c moves back to the valve cover 5b, increasing the load on the valve cover 5b, making the valve cover 5b more likely to bend downward. However, the valve cover 5b is supported by the jacks 104, 104 on the concrete base F, preventing bending, and allowing the valve body 5c to move smoothly.

In addition, the housing 10 is connected to the fluid pipe 2 by an adjustment bolt (not shown), and the pressure rings 13, 13 are connected to the ends 2H, 2T of the fluid pipe 2 by bolts (not shown). Therefore, even if a sudden change in flow occurs when cutting the fluid pipe 2, causing the fluid pipe 2 to jump up, the fluid pipe 2 can be prevented from coming out of the housing 10 and the pressure rings 13, 13.

In addition, even if the housing 10 is filled with clean water and the total weight of the housing 10 increases further, the housing 10 is supported by the jacks 4, 4 and the protective concrete C1, so most of the total weight of the housing 10 is prevented from acting directly on the ends 2H, 2T of the severed fluid pipe 2.

This prevents the ends 2H and 2T from tilting, which not only prevents unintended loads from being applied to the flow paths connected to the ends 2H and 2T, but also ensures the opening area required to remove the cutter consisting of the hole saw 8a and center drill 8b after cutting the fluid pipe 2. This allows the hole saw 8a and center drill 8b to be easily removed.

In addition, the jacks 4, 4 and the protective concrete C1 prevent the housing 10 from rotating around the axis of the fluid pipe 2, so the housing 10 remains stably supported even if the total weight of the housing 10 increases further.

In addition, the arm 10A and the end 2H including the exposed portion of the arm 10A side of the fluid pipe 2 are supported by the protective concrete C1 and integrated with the base concrete F, so they are kept aligned with the arm 10A. The same is true for the arm 10B and the end 2T including the exposed portion of the arm 10B side.

The bottom wall 31a of the housing 10 is located far enough away from the fluid pipe 2 that the hole saw 8a and center drill 8b are unlikely to come into contact with each other when cutting the fluid pipe 2.

In addition, when connecting the fluid pipe 2, by connecting a drain pipe (not shown) to the drain pipe 35 provided at the bottom of the body 31, cutting chips generated when cutting the fluid pipe 2 with the hole saw 8a can be discharged to the outside together with the fluid.

After that, although not shown directly, the hole saw 8a and center drill 8b are raised up together with the section of the fluid pipe 2, and the valve body 5c of the working valve 5 advances from the valve cover 5b into the valve box 5a to a closed state. This prevents leakage of clean water and allows the cutting device 8 to be removed from the working valve 5 while maintaining an uninterrupted flow state.

Next, a flow control installation process is performed in which a butterfly valve 14 is installed as a flow control valve in the housing 10. As shown in FIG. 9, in the flow control installation process, first, the upper flange portion 5f of the valve box 5a and the lower flange portion 9c of the cylindrical member 9a of the insertion device 9 are connected with bolts and nuts (not shown). Next, the working valve 5 is opened, and the drive mechanism 7 of the insertion device 9 is operated to lower the open butterfly valve 14 and place it in the housing 10. Note that a gasket (not shown) is interposed between the flange portion 5f of the valve box 5a and the flange portion 9c of the cylindrical member 9a, so that the valve box 5a and the cylindrical member 9a are connected in a sealed state.

Thus, even if the total weight of the housing 10 increases with the addition of the weights of the working valve 5, the insertion device 9, and the butterfly valve 14, the housing 10 is supported by the jacks 4, 4 and the protective concrete C1, so it is possible to prevent most of the total weight of the housing 10 from acting directly on the ends 2H, 2T of the fluid pipe 2. This prevents the ends 2H, 2T of the fluid pipe 2 from tilting, allowing the butterfly valve 14 to be inserted stably.

In particular, when installing the butterfly valve 14, the insertion device 9 temporarily presses the butterfly valve 14 downward toward the inner bottom surface of the housing 10, applying a load to it, but the jacks 4, 4 and protective concrete C1 can support it against the weight of the working valve 5, insertion device 9, etc., and the downward load.

In addition, the arm 10A and the end 2H of the fluid pipe 2 are supported by the protective concrete C1 together with the arm 10A and are integrated with the concrete base F, so that even if the weight of the housing 10 changes, they remain aligned with the arm 10A. The same is true for the arm 10B and the end 2T.

Before inserting the butterfly valve 14 into the housing 10, a hole 71 formed in the top of the upper housing 20 is connected to a hole 72 formed in the bottom of the cylindrical member 9a by a connecting pipe 73 to communicate the inside of the housing 10 with the inside of the cylindrical member 9a, and water pressure approximately equal to that in the fluid pipe 2 is applied to the inside of the cylindrical member 9a while air is released from an air release valve (not shown) provided at the top of the cylindrical member 9a. After confirming that the air has been released from the cylindrical member 9a, the air release valve (not shown) is closed, and with the inside of the housing 10 and the inside of the cylindrical member 9a at approximately the same pressure, the working valve 5 is opened, and the drive mechanism 7 of the insertion device 9 is operated to lower the butterfly valve 14.

When the inside of the housing 10 and the inside of the cylindrical member 9a are to be made substantially equal in pressure, the drain pipe 35 may be connected to the hole 72. The holes 71 and 72 are provided with opening and closing valves (not shown).

Then, the butterfly valve 14 is inserted into the housing 10, and placed with the packings 40, 41 pressed against the seat formed in the housing 10. Here, the packing 40 is fixed to both sides and the bottom of the partition wall 43 that separates the ends 2H, 2T of the fluid pipe 2 together with the valve body 42. The packing 41 is fixed to the outer periphery of the disk-shaped lid 44 that closes the neck 21 of the housing 10. These packings 40, 41 are connected so as to be continuous.

Furthermore, referring to FIG. 10, a plurality of clamping bolts 25 arranged in the circumferential direction of the neck 21 are advanced to the inner diameter side of the neck 21. More specifically, the clamping bolts 25 penetrate the peripheral wall of the neck 21 and are screwed into the female threads of the through-holes formed in the peripheral wall. The clamping bolts 25 advance to the inner diameter side of the neck 21 by rotating in a predetermined direction, so that the cover 44 of the butterfly valve 14 can be abutted against the cover 44 to prevent it from coming off. Note that the clamping means such as the clamping bolts 25 may be separate from the advancing member that is screwed into the female threads of the through-holes and the abutting member that moves with the advancing member to abut against the fluid control valve, and the number and arrangement of the members may be changed as appropriate. In addition, a recess may be provided on the inner surface of the peripheral wall, and a plate or the like may be fitted into and fixed.

Then, close the opening/closing valves (not shown) of the holes 71 and 72 (or the drain pipe 35 and the hole 72), open the air bleed valve (not shown) provided at the top of the cylindrical member 9a, and check that the packing 41 of the butterfly valve 14 has stopped water flowing, and then remove the connecting pipe 73, the insertion device 9, and the working valve 5 from the housing 10. The jacks 104, 104 are removed along with the working valve 5.

Next, a gasket 46 is placed between the inner circumferential surface of the neck 21 and the ring 45 fitted onto the lid 44, and then the flange 21a of the neck 21 and the body lid 11 are fastened together with bolts and nuts (not shown). This creates a seal between the inner circumferential surface of the neck 21 and the lid 44. Needless to say, a gasket is placed between the flange 21a of the neck 21 and the body lid 11 to provide a seal.

Then, the drilled hole 16 is backfilled (not shown) to complete the flow control installation process. It is preferable to leave the area around the valve operating unit 47 unbackfilled, install a valve box (not shown), and remove the valve chest cover (not shown) that closes the top opening of the valve box so that the valve operating unit 47 can be operated from the valve chest. Also, instead of backfilling the drilled hole 16 from the state shown in FIG. 10, the entire drilled hole 16 may be made into a valve chest.

In this way, the uninterrupted flow method of this embodiment can be performed to install the butterfly valve 14 at a specified location in the fluid pipe 2 while maintaining an uninterrupted flow state.

The method of sealing the cut surfaces 20a, 30a is not limited to welding, but may be such that the upper housing 20 and the lower housing 30 are fastened together with bolts and nuts with a sealing member interposed therebetween. Also, as described above, after the main body lid 11 is attached to the housing 10, the jacks 4, 4 may be removed, and by recovering the jacks 4, 4, they can be reused in other construction work.

Although a crane has been used as an example of a means for holding the housing 10, this is not limiting, and jacks 4, 4 may also be used as the holding means. In other words, rough alignment may be performed by extending and retracting the jacks 4, 4 while the housing 10 is placed on the jacks 4, 4.

In addition, the flow control device has been described as being a butterfly valve 14, but is not limited to this and may be other types of valves such as a switching valve, gate valve, ball valve, etc., or may be a partition plate, plug, etc., and may be modified as appropriate.

The fluid control removal process for removing the butterfly valve 14 installed in the housing 10 will not be described in detail, but similar to the fluid control installation process described above, the working valve 5 is attached above the upper housing 20, and the weight of the valve cover 5b of the working valve 5 is supported on the upper surface Fa by jacks 104, 104 (see Figure 6). Next, the cylindrical member 9a of the insertion device 9 is attached above the working valve 5, and the drive mechanism 7 is attached above that (see Figure 9). After that, the working valve 5 is opened and the drive mechanism 7 is operated to pull out the butterfly valve 14 from the housing 10 and raise it, and the working valve 5 is closed.

As explained above, the uninterrupted flow method according to the embodiment of the present invention involves installing an operating valve 5 capable of opening and closing the upper opening 10C of a housing 10 above the housing 10, which is hermetically attached to an existing fluid pipe 2 buried underground, and performing at least one of the following operations in an uninterrupted state: installation of a butterfly valve 14 inside the housing 10 (fluid control installation process), removal (fluid control removal process), and cutting of the existing fluid pipe 2 (removal process). In each operation process, the load of the valve cover 5b is supported by jacks 104, 104 placed on the upper surface Fa of the foundation concrete F.

By this, the load of the valve cover 5b protruding laterally from the valve box 5a is supported by the strong base concrete F via the jacks 104, 104, which prevents the tip side of the valve cover 5b from bending downward due to the load and the application of an unbalanced load to the valve body 5c. This allows the valve body 5c to move smoothly between the closed position of the valve box 5a and the retracted position of the valve cover 5b, and prevents the seal member of the valve body 5c from coming into strong contact with the inner surface of the valve cover 5b and rubbing it due to the unbalanced load, which would cause a decrease in sealing performance.

In addition, the load of the valve cover 5b is supported by the strong base concrete F via the jacks 104, 104, and the load of the valve cover 5b is not applied to the existing fluid pipe 2, preventing damage to the fluid pipe 2.

In addition, height-adjustable jacks 104, 104 are used as support means, allowing adjustment according to the height from the top surface Fa of the base concrete F to the valve cover 5b, so support can be provided in response to unevenness in the top surface Fa.

In addition, the load of the valve cover 5b is supported by multiple jacks 104, 104, so that the height of multiple points on the valve cover 5b can be adjusted individually, allowing the valve cover 5b to be maintained approximately horizontal.

The valve cover 5b protrudes from the valve box 5a in the axial direction of the fluid pipe 2, and jacks 104, 104 are arranged on both the front and rear sides of the fluid pipe 2, so that the load of the valve cover 5b is prevented from being applied to the fluid pipe 2, and both sides of the valve cover 5b in the front-to-rear width direction can be stably supported.

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.

For example, in the above embodiment, the jacks 104, 104 as support means are placed on the upper surface Fa of the base concrete F that constitutes part of the foundation, but the present invention is not limited to this, and may be placed on the front and rear upper surfaces C1b, C1b of the protective concrete C1 that is part of the foundation, as in the case of the jacks 114, 114 as support means of the present invention in modified example 1 shown in Figure 11. In this way, the jacks 114, 114 can be placed on the upper surfaces C1b, C1b of the protective concrete C1 that are closer to the lower surface 5i of the valve cover 5b than the upper surface Fa of the base concrete F, and therefore the jacks 114, 114 can be shortened, which not only makes the installation work of the jacks 114, 114 easier, but also improves stability. Although not specifically shown, jacks 104, 104 placed on the top surface Fa of the base concrete F and jacks 114, 114 placed on the top surfaces C1b, C1b of the protective concrete C1 may be used in combination.

In the above embodiment, the valve cover 5b protrudes from the valve box 5a in the axial direction of the fluid pipe 2, but the present invention is not limited to this. As long as it protrudes laterally (horizontally) from the valve box 5a, it may protrude horizontally in a direction different from the axial direction of the fluid pipe 2 (for example, a front-to-rear direction perpendicular to the axis of the fluid pipe 2), as in the modified example 2 of the present invention shown in Figures 12(a) and (b). Even in such a case, the load of the valve cover 5b can be supported by left and right jacks 124, 124 placed on the upper surface Fa of the base concrete F, which is the foundation.

In this case, since there is no fluid pipe 2 below the valve cover 5b, the placement position of the jacks 124, 124 is not limited, so the jacks 124, 124 can support multiple points on the most stable tip side of the underside 5i of the valve cover 5b. Furthermore, a third jack can be placed between the left and right jacks 124, 124, closer to the tip side, to support three points on the underside 5i.

In addition, in the above embodiment and modified example, the load of the valve cover 5b is supported by jacks 104, 104, jacks 114, 114, and jacks 124, 124 as support means placed on the foundation, such as the base concrete F and protective concrete C1 provided inside the excavation hole 16, but the present invention is not limited to this, and the load of the valve cover 5b may be supported by jacks 134, 134 as support means placed on the ground GL of the ground that spreads around the excavation hole 16, as in modified example 3 of the present invention shown in Figures 13 and 14.

In this case, the working valve 5 needs to be located above the ground GL, so first, a spacer 50 is attached as an extension to the top of the upper housing 20. The spacer 50 is made of a cylindrical tube 51 whose inside diameter is the same as the body 31 of the upper housing 20, and flanges 52a, 52b are provided on both ends of the cylindrical tube 51 in the axial direction, protruding in the outer diameter direction.

The spacer 50 thus configured is hung by a crane into the upper opening 10C of the upper housing 20, and the flange portion 21a of the upper housing 20 and the flange portion 52a of the spacer 50 are fastened together with bolts and nuts (not shown). A gasket (not shown) is interposed between the flange portion 21a of the neck portion 21 and the flange portion 52a of the spacer 50, so that the upper housing 20 and the spacer 50 are connected in a sealed state. Next, the working valve 5 is hung by a crane into the upper opening of the spacer 50, and the flange portion 52b of the spacer 50 and the flange portion 5e of the valve box 5a are fastened together with bolts and nuts (not shown). A gasket (not shown) is interposed between the flange portion 52b of the spacer 50 and the flange portion 5e of the valve box 5a, so that the spacer 50 and the valve box 5a are connected in a sealed state.

In this way, by disposing the spacer 50 as an extension between the housing 10 and the working valve 5, the working valve 5 is positioned above the ground level GL. This eliminates the need to secure installation space for the working valve 5 by excavating, making it possible to reduce the excavation range and simplify the work.

Then, jacks 134, 134 may be placed on the underside of the valve cover 5b on the ground GL, and the load of the valve cover 5b may be supported by the jacks 134, 134 placed on the ground GL of the ground G. In this way, the valve body 5c is prevented from being subjected to an unbalanced load, so that the valve body 5c of the working valve 5 can move smoothly and maintain its sealing performance. In addition, since there is no need for an operator to enter the excavation hole 16 to install the jacks 134, 134, workability is favorably improved. Note that the ground GL in this embodiment is the ground in its natural state without excavating the ground G, but it is preferable to perform leveling work to form it into a horizontal surface. The ground G may also be slightly excavated to expose good quality ground. In addition, it is preferable to strengthen the retaining wall of the excavation hole 16 near the placement position of the jacks 134, 134, and in this way, the supporting force of the ground G can be secured.

In addition, here, an embodiment is shown in which a spacer 50 consisting of a cylindrical tube 51 with flanges 52a, 52b formed on both ends is used as the extension portion, but the present invention is not limited to this, and the extension portion may be configured as a cylindrical portion extending downward from the underside of the valve box 5a, or may be configured as a cylindrical portion extending upward from the upper opening 10C of the housing 10. In other words, the extension portion may be integrally formed with either the valve box 5a or the housing 10.

In addition, in the above-mentioned modified example 3, the valve cover 5b is exemplified as protruding from the valve box 5a in the axial direction of the fluid pipe 2, but the present invention is not limited to this, and as long as it protrudes laterally (horizontally) from the valve box 5a, it may protrude horizontally in a direction different from the axial direction of the fluid pipe 2 (for example, a front-to-rear direction perpendicular to the axis of the fluid pipe 2), as in modified example 4 of the present invention shown in Figures 15 and 16. Even in such a case, the load of the valve cover 5b can be supported by jacks 144, 144 placed on the ground GL, which is the foundation.

In this case, since there is no fluid pipe 2 below the valve cover 5b, the placement position of the jacks 144, 144 is not restricted, so the most stable position on the underside 5i of the valve cover 5b can be supported by the jacks 144, 144.

In addition, in the above embodiment, the support means for supporting the load of the valve cover 5b is exemplified by jacks 104, 104, jacks 114, 114, jacks 124, 124, jacks 134, 134, or jacks 144, 144 with height adjustment function, but the present invention is not limited to this, and does not necessarily have to have height adjustment function, and may be square timber or H-shaped steel material that cannot be adjusted in height.

In the above embodiment, the jacks 104, 104, jacks 114, 114, jacks 124, 124, jacks 134, 134, and jacks 144, 144 are arranged in opposing positions across the fluid pipe 2 in the radial direction, but this is not limited thereto, and multiple jacks may be arranged spaced apart in the lateral extension direction of the valve cover 5b. In this way, the height position of the jacks can be changed between the tip side of the valve cover 5b, which has a relatively large amount of deflection, and the base end side, which has a small amount of deflection, and horizontal adjustment can be performed with higher precision.

In addition, in the above embodiment, the jacks 104, 104, jacks 114, 114, jacks 124, 124, jacks 134, 134, or jacks 144, 144 as support means are placed directly on the foundation or ground, but the present invention is not limited to this. It is also possible to provide other support means such as H-beams or beams between the foundation or ground to adjust the height, and then use the jack bolts to fine-tune the height.

In the above embodiment, the uninterrupted flow method includes a cutting process (FIG. 8) in which the existing fluid pipe 2 is cut without interrupting the flow, a flow control installation process (FIG. 9) in which the butterfly valve 14 serving as a flow control is installed in the existing fluid pipe 2 without interrupting the flow, and a flow control removal process (not shown) in which the butterfly valve 14 serving as a flow control is removed from the existing fluid pipe 2 without interrupting the flow. The uninterrupted flow method of the present invention can be applied to the case where at least one of the multiple processes, such as the cutting process (FIG. 8), flow control installation process (FIG. 9), and flow control removal process (not shown), is performed.

For example, when only the above-mentioned cutting process (Figure 8) is performed, the load of the valve cover 5b may be supported by a support means placed on the foundation or ground after the working valve 5 is installed above the housing 10 that is hermetically attached to the existing fluid pipe 2.

The fluid control device is not limited to the butterfly valve 14 or inner lid (not shown), but may be a switching valve, gate valve, ball valve, partition plate, plug, etc., as long as it is capable of controlling the fluid.

In addition, in the above embodiment, the space between the fluid pipe and the housing is described as being sealed by a sealing member, but this is not limited thereto, and the space may be sealed by welding, or so-called side rings may be welded to the fluid pipe and the housing, respectively, and may be modified as appropriate.

In the above embodiment, the excision device is described as a hole saw having a cutter, but it is not limited to this and may be a drilling machine, a wire saw, a cutting tool, an end mill, or may be modified as appropriate. In other words, the fluid pipe that constitutes the flow path is not limited to being cut, as long as the fluid can flow through at least a portion of the cut-out.

In the above embodiment, the fluid pipe 2 as an existing fluid pipe is buried underground, but the present invention is not limited to this. The fluid pipe may be exposed above ground, such as a plant pipe, i.e., a fluid pipe that is extended above the ground surface. In this case, although not shown, a temporary construction stand (supporting means) may be assembled by placing H-beams or the like on the ground or foundation around the fluid pipe, and a jack (supporting means) or the like may be installed between the temporary construction stand and the operation valve to support it. Note that the plant pipe may be installed at a height of several meters or more above the ground, so it is preferable to assemble and install the temporary construction stand according to the height of the pipe.

In the above embodiment, the cutting process is performed while the existing fluid pipe 2 is in an uninterrupted flow state, and the existing fluid pipe 2 is cut and divided in the axial direction of the pipe, and then the pieces of the fluid pipe 2 are removed. However, the present invention is not limited to this. The cutting operation in which the load of the valve cover is supported by a support means placed on the ground or foundation may be an operation to cut at least a part of the existing fluid pipe in an uninterrupted flow state, and may be, for example, an operation to drill a part of the pipe wall without dividing the existing fluid pipe, or an operation that does not include removing the pieces by drilling a part of the pipe wall with an end mill or the like.

Reference Signs List 2 Fluid pipe 5 Working valve 5a Valve box 5b Valve cover 5c Valve body 5d Through passage 5e, 5f Flange portion 5g Valve stem 5h Drive portion 5i Underside 7 Drive mechanism 8 Excision device 9 Insertion device 9a Cylindrical member 9c Flange portion 10 Housing 10C Upper opening 13 Press ring 14 Butterfly valve (fluid control)
16: drilled hole 20: upper housing 30: lower housing 50: spacer 104: jack (support means)
104a: base 104b: bolt 104c: plate 104d: upper end 104e: recess 114: jack (support means)
124 Jack (support means)
134 Jack (support means)
144 Jack (support means)
148 Valve box C1 Protective concrete (foundation)
C1a Right side C1b Top F Bottom concrete (foundation)
Fa Top surface G Ground GL Ground (ground)

Claims (5)

A method for uninterrupted flow in which a valve capable of opening and closing an upper opening of a housing is installed above a housing that is hermetically attached to an existing fluid pipe, and at least one of the following operations is performed without interrupting flow: installation and removal of a flow regulator in the housing, and cutting of the existing fluid pipe;
The working valve is adapted to open and close an upper opening of the housing by moving a valve body between a valve box attached to the upper part of the housing and a valve cover protruding laterally from the valve box,
A method for preventing flow interruption, characterized in that during the above-mentioned operation, the load of the valve cover is supported by a support means placed on the ground or foundation. The uninterrupted flow construction method according to claim 1, characterized in that the support means includes a height-adjustable jack. The uninterrupted flow construction method according to claim 2, characterized in that the load of the valve cover is supported by a plurality of the jacks. The valve cover protrudes from the valve body in a pipe axis direction of the existing fluid pipe,
4. The method according to claim 1, wherein the support means is disposed on both sides of the existing fluid pipe. The uninterrupted flow construction method according to claim 1, characterized in that the ground is the ground surrounding a hole excavated to install the housing.

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