Patent Description:
In a fluid pipeline structure, for example, a renewal work where a fluid pipe forming a pipeline or piping equipment such as a fire hydrant is renewed without flow disruption (without water disruption), or an earthquake resistance work where piping equipment for earthquake resistance is replaced without flow disruption is performed.

If one example of a method of the renewal and earthquake resistance work is described, a valve device including a valve body which can open and close a flow path from a direction intersecting a flow path axis is mounted on a connection port portion side of a branch pipe of a fluid pipe (one example of a pipe) that is positioned in a portion upstream of a work target region, or on a connection port portion side of a branch pipe of a split T-shaped pipe (one example of a pipe) which has a split structure and is externally mounted and fixed on the fluid pipe. A drilling device is mounted on the valve device, and in a state where the valve body is opened, a drilling portion of the drilling device is delivered inward to form a through-hole in a pipe wall of the fluid pipe. Subsequently, the drilling device is removed from the valve device in a state where the valve body is closed, and a flow path-closing device is mounted on the valve device. In a state where the valve body is opened, a flow path-closing portion of the flow path-closing device is delivered into a work target region in the pipeline from the through-hole of the fluid pipe, and the flow path-closing portion blocks an in-pipe flow path of the fluid pipe. A predetermined work step of performing a renewal and earthquake resistance work is executed in a state where the in-pipe flow path is blocked. Thereafter, a valve removal method of removing the flow path-closing device from the valve device in a state where the valve body is closed, and removing the valve device from the branch pipe in a state where the branch pipe is closed in a sealed manner is executed.

In the foregoing valve removal method, in the related art, as disclosed with reference to <FIG> of PTL <NUM>, a closing piece is inserted into a receiving portion of a connection portion corresponding to the connection port portion of the branch pipe, and an expansion member made of a rubber material in the closing piece is expanded to a closed state by an insertion device main body. In this closed state, the plug valve and a case body corresponding to the valve device are removed.

Thereafter, as disclosed with reference to <FIG>, a pressing ring which comes into contact with the closing piece from a downstream side to prevent the pullout movement of the closing piece is inserted into the receiving portion of the connection portion. A flange portion of the pressing ring and a flange portion of the receiving portion are fixed by bolts and nuts. Subsequently, a closing lid which closes a central opening of the pressing ring in a sealed state is fixed to the pressing ring by bolts. A bolt provided in a central portion of the closing lid is screwed into a crimping bolt of the closing piece, so that the closing piece is pulled toward and fixed to the pressing ring.

The foregoing valve removal method requires a step of closing the inside of the receiving portion of the connection portion using the closing piece, a step of fixing and coupling the flange portion of the receiving portion and the flange portion of the pressing ring to each other using the bolts and the nuts, a step of fixing the closing lid, which closes the central opening of the pressing ring in a sealed state, to the pressing ring using the bolts, and a step of screwing the bolt, which is provided in the central portion of the closing lid, onto the crimping bolt of the closing piece to pull and fix the closing piece to the pressing ring, and it takes a long time to perform the valve removal method.

Moreover, in addition to the plug valve, the closing piece that closes the inside of the receiving portion of the connection portion in a sealed manner, the pressing ring that is fixed to the receiving portion in a state where the pressing ring comes into contact with the closing piece to prevent the pullout movement of the closing piece, and the closing lid including the bolt that closes the central opening of the pressing ring in a sealed manner and pulls and fixes the closing piece to the pressing ring are required, and the work costs of the valve removal method increase, which is a problem.

The present invention is made in light of the foregoing circumstances, and a main object of the present invention is to provide a valve removal method of a fluid pipeline structure, and a fluid pipeline structure and a valve device useful for the method, in which with rational improvement using a part of the valve device, unnecessary valve components of the valve device can be efficiently removed from the connection port portion of the pipe in a state where an opening of a connection port portion of a pipe is securely sealed, and work costs can be reduced by reducing the number of closing components.

The invention is a valve removal method of a fluid pipeline structure according to the method steps of claim <NUM>, a valve device according to the technical features of claim <NUM> and a fluid pipeline structure according to claim <NUM>. Advantageous embodiments of the invention are disclosed in the dependent claims.

According to a first aspect of the present invention, there is provided a valve removal method of a fluid pipeline structure according to the method steps of claim <NUM>.

According to this configuration, when the valve device is removed from the pipe connected to the fluid piping system, the valve body fixing step is executed, so that the valve body at the closed valve position is fixed to the connection port portion of the pipe in a sealed manner. Subsequently, the valve component removing step is executed, so that while the valve body which is fixed to the connection port portion of the pipe in a sealed manner is left, other unnecessary valve components of the valve devices are removed from the connection port portion of the pipe.

Accordingly, since the valve body of the valve device can be used as it is, as a plug member for closing a pipe end which an opening of the connection port portion of the pipe is closed in a sealed manner, it is possible to eliminate a plurality of closing components such as a closing piece that closes the inside of the connection port portion of the pipe in a sealed manner and a closing lid including a pressing ring that is fixed to a receiving portion in a state where the pressing ring comes into contact with the closing piece to prevent the pullout movement of the closing piece and a bolt for closing a central opening of the pressing ring in a sealed manner and pulling and fixing the closing piece to the pressing ring, which are described in the method of the related art.

Moreover, since the valve body of the valve device is at the closed valve position where the opening of the connection port portion of the pipe is sealed, the execution of the valve body fixing step is completed only by fixing the valve body at the closed valve position as it is, to the connection port portion of the pipe.

Therefore, with the foregoing rational improvement using the valve body of the valve device, it is possible to efficiently remove an unnecessary valve component of the valve device from the connection port portion of the pipe in a state where the opening of the connection port portion of the pipe is securely sealed. Moreover, it is possible to reduce work costs by reducing the number of closing components.

Preferably, between a valve device mounting step of mounting the valve device on the connection port portion of the pipe and the valve body fixing step, a work equipment mounting step of mounting work equipment on the valve device, a predetermined work step of operating the valve body of the valve device to an open valve position and delivering a work portion of the work equipment into a work target region in a pipeline from an opening of the connection port portion to perform a predetermined work, and a work equipment removing step of taking the work portion out of the pipe after the predetermined work step is finished, operating the valve body to the closed valve position, and then removing the work equipment from the valve device are executed.

According to this configuration, the valve device mounted on the connection port portion of the pipe is generally used as a valve device for a predetermined work that delivers a work portion of a work equipment into a work target region in a pipeline to perform the predetermined work without flow disruption. For this reason, after the work equipment is removed from the valve device, an unnecessary portion of the valve device is removed from the connection port portion of the pipe.

In this case, as described above, while the valve body which is fixed at the closed valve position in a sealed manner is left on the connection port portion of the pipe, it is only necessary to remove other unnecessary valve components of the valve device from the connection port portion of the pipe; and thereby, it is possible to efficiently perform the work from the valve device mounting step to the valve component removing step through the work equipment mounting step, the predetermined work step, the equipment removing step, and the valve body fixing step.

Preferably, the valve body fixing step includes a valve body pressing step of pressing the valve body at the closed valve position against a connection end surface of the connection port portion in a sealed state using a valve body-pressing portion provided in a valve housing of the valve device, and a fastening and fixing step of fixing the valve body in a sealed state to the connection port portion side of the pipe using a first fastening portion.

According to this configuration, when the valve body fixing step of fixing the valve body of the valve device at the closed valve position to the connection port portion of the pipe in a sealed state is executed, in the valve body pressing step, the valve body at the closed valve position is securely pressed toward the connection end surface of the connection port portion against the fluid pressure by the valve body-pressing portion provided in the valve housing of the valve device, so that the sealed state can be maintained. The valve body can be securely and easily fixed to the connection port portion side of the pipe in a sealed state by the fastening and fixing step executed in this pressed state.

Preferably, the valve component removing step includes a step of removing a valve housing of the valve device, to which at least a part of a remaining portion of the valve device other than the valve body is integrally assembled, from the connection port portion side of the pipe.

According to this configuration, when other unnecessary valve components of the valve device are removed from the connection port portion of the pipe while the valve body which is fixed to the connection port portion of the pipe in a sealed manner is left, also the other unnecessary valve components which are integrally assembled to the valve housing can be simultaneously removed by detaching the valve housing from the connection port portion side of the pipe; and thereby, it is possible to efficiently and easily perform the work of removing the other valve components including the valve housing.

According to a second aspect of the present invention, there is provided a fluid pipeline structure according to the technical features of claim <NUM>.

According to this configuration, since the valve body has a smaller external shape than that of the installation port portion of the valve housing, and is fixed at the closed valve position to the connection port portion of the pipe in a sealed manner, when the valve housing which is another unnecessary valve component is removed while the valve body is left at the closed valve position, it is possible to prevent the valve body from being caught by a peripheral edge of the installation port portion of the valve housing. Accordingly, it is possible to smoothly pull out the valve housing along the flow path axis direction, and it is possible to efficiently and easily perform the work of removing other unnecessary valve components.

Preferably, the pipe is provided with a load receiving portion which protrudes further outward in a radial direction than an outer peripheral surface of the flange of the connection port portion and on which the installation port portion of the valve housing is placed and supported, so as to be detachable, and in a state where the installation port portion of the valve housing is placed and supported on the load receiving portion, a sliding guide surface inside the valve housing, which guides sliding of the packing of the valve body, and the ring-shaped valve seat surface of the connection port portion are disposed at the same or substantially the same height position.

According to this configuration, when the installation port portion of the valve housing is placed and supported on the load receiving portion that protrudes further outward in the radial direction than the outer peripheral surface of the flange of the connection port portion, the sliding guide surface inside the valve housing, which guides the sliding of the packing of the valve body, and the ring-shaped valve seat surface of the connection port portion are at the same or substantially the same height position; and thereby, it is possible to smoothly perform the opening and closing operation of the valve body. Moreover, since the load receiving portion is configured to be attachable to and detachable from the pipe, it is not required that a large pipe is remade as when the load receiving portion is formed integrally with the flange of the connection port portion; and thereby, it is possible to securely and easily install the valve housing on the flange of the existing pipe while reducing the initial investment.

Preferably, a hole closing tool including a sealing and closing portion which closes a coupling hole of the flange in a sealed state is detachably mounted between a pipe main body including the pipe and the flange, and the hole closing tool is provided with the load receiving portion.

According to this configuration, the installation port portion of the valve housing is externally mounted on the flange of the connection port portion of the pipe, and the hole closing tool is mounted between the pipe main body including the pipe and the flange; and thereby, the coupling hole of the flange can be securely closed in a sealed state by the sealing and closing portion of the hole closing tool. Accordingly, when the valve body is at the open valve position, it is possible to prevent the fluid from leaking outside from the coupling hole of the flange. Moreover, since the load receiving portion on which the installation port portion of the valve housing is placed and supported is provided using the hole closing tool, it is possible to simplify the mounting structure where the load receiving portion is detachably provided, and reduce the costs.

Preferably, inside the valve housing of the valve device, a rotary arm which is rotationally operable around an axis parallel to or substantially parallel to a flow path axis of the connection port portion of the pipe is provided and a linkage mechanism which causes the valve body to reciprocate between a closed valve position and an open valve position in conjunction with a rotation of the rotary arm is provided, and the linkage mechanism is configured to be changeable between a linked state and a non-linked state in the flow path axis direction and to be changed to the non-linked state as the valve housing moves along the flow path axis direction to separate from the valve body fixed to the connection port portion side.

According to this configuration, the rotary motion of the rotary arm provided inside the valve housing of the valve device is changed to the reciprocating motion of the valve body by the linkage mechanism. For this reason, for example, compared to when the valve body is coupled to the tip of the operating member penetrating through the valve housing and the push and pull operation of the operating member causes the valve body to reciprocate between the closed valve position and the open valve position, it is possible to reduce the size of the valve device by an amount corresponding to a protrusion of the operating member. Accordingly, it is possible to advantageously excavate a work pit for an underground piping.

Moreover, the linkage mechanism which links the rotary arm and the valve body is configured to be changeable between the linked state and the non-linked state in the flow path axis direction. For this reason, when the valve housing which is another unnecessary valve component is removed while the valve body which is fixed to the connection port portion of the pipe in a sealed manner is left, an operation of decoupling the linkage mechanism is not required. Accordingly, since it is only necessary to pull out the valve housing along the flow path axis direction, it is possible to efficiently and easily perform the work of removing other unnecessary valve components.

Preferably, a linear guide portion which guides the valve body to move in a non-rotatable state between a closed valve position and an open valve position in a linear direction is provided on an inner surface side of the valve housing.

According to this configuration, the movement of the valve body between the closed valve position and the open valve position in the linear direction can be smoothly guided along the linear guide portion provided on the inner surface side of the valve housing. Moreover, in this case, since the orientation of the valve body is not changed, the valve body operated to the closed valve position can be easily fixed to the connection port portion of the pipe in a sealed manner.

According to a third aspect of the present invention, there is provided a valve device according to the technical features of claim <NUM>.

According to this configuration, the valve body of the valve device can be used as it is, as a plug member for closing a pipe end which closes the opening of the connection port portion of the pipe in a sealed manner. Accordingly, it is possible to efficiently remove an unnecessary valve component of the valve device from the connection port portion of the pipe in a state where the opening of the connection port portion of the pipe is securely sealed. Moreover, it is possible to reduce work costs by reducing the number of closing components.

Embodiments of the present invention will be described based on the drawings.

<FIG> and <FIG> illustrate a valve device <NUM> that is attachable to and detachable from a connection port portion 16A of a pipe <NUM> connected to a fluid piping system illustrated in <FIG>. In a valve housing <NUM>, the valve device <NUM> includes a valve body <NUM> that is openable and closeable in a direction orthogonal to (one example of an intersecting direction) a flow path axis (branch axis) of the connection port portion 16A.

For example, when a renewal of or an earthquake resistance work on a pipeline forming the fluid piping system is started, the valve device <NUM> is mounted on the connection port portion 16A of the pipe <NUM>, which forms a part of the pipeline, in a sealed state (watertight state), and when the renewal or the earthquake resistance work is finished, without flow disruption (without water disruption), the valve device <NUM> is removed from the connection port portion 16A of the pipe <NUM>. For this reason, the valve device <NUM> has a function and a structure that are useful in executing a valve removal method.

In addition, as the pipe <NUM> on which the valve device <NUM> is mounted, there are various forms of pipes in the related art. For example, in the embodiment, as illustrated in <FIG>, as an example of the pipe <NUM>, there is provided a branch pipe (hereinafter, referred to as a branch pipe <NUM>) of a split T-shaped pipe (one example of a pipe main body) <NUM> that has a split structure and is externally mounted and fixed on a fluid pipe (water pipe) <NUM> in a sealed state (hereinafter, may be referred to as a watertight state). Besides, examples of the pipe <NUM> can include a branch pipe that integrally protrudes from a pipe wall of the fluid pipe, a pipe forming a part of a fluid machine, and the like which are not illustrated.

Furthermore, the fluid pipe <NUM> of this embodiment is a ductile cast iron pipe forming a water pipe that transports tap water (drinking water) which is one example of a fluid; however, other cast iron pipes, steel pipes, resin pipes, or the like can be used as the fluid pipe <NUM>. In addition, examples of the fluid include industrial water, gas such as manufactured gas, or the like in addition to tap water.

As illustrated in <FIG>, the split T-shaped pipe <NUM> used in this embodiment includes three split couplers <NUM> of which each has a partial cylindrical shape and which are split in a pipe circumferential direction and are externally mountable on the fluid pipe <NUM> from a pipe radial direction. Among coupling flange portion 11A which are formed in both end portions of the split couplers <NUM> in the pipe circumferential direction, the coupling flange portions 11A adjacent to each other in the pipe circumferential direction are detachably fixed and coupled to each other by a plurality of sets of bolts <NUM> and nuts <NUM> which are one example of fastening means.

In addition, a seal member <NUM> made of rubber is installed on inner surfaces of the split couplers <NUM> to seal a gap between the inner surfaces thereof and an outer peripheral surface of the fluid pipe <NUM> and a gap between split surfaces of both split couplers <NUM> adjacent to each other in the circumferential direction in a watertight state. The branch pipe <NUM> having a cylindrical shape integrally protrudes from a central portion in the pipe circumferential direction and a central portion in a pipe axis direction in one split coupler <NUM> that is disposed above an upper portion of the fluid pipe <NUM>. A branch flow path 16B in the branch pipe <NUM> opens upward along a branch axis (flow path axis) Y orthogonal to a pipe axis X of the fluid pipe <NUM>.

As illustrated in <FIG> and <FIG>, a ring-shaped valve seat surface <NUM> which has an annular shape and with which a first packing <NUM> of the valve body <NUM> of the valve device <NUM> comes into watertight contact protrudes from a connection end surface 16a of the connection port portion 16A of the branch pipe <NUM>.

In addition, as illustrated in <FIG> and <FIG>, a first flange <NUM> having an annular shape and protruding outward in the pipe radial direction is integrally formed on an outer peripheral surface of the connection port portion 16A of the branch pipe <NUM>. As illustrated in <FIG>, first bolt insertion holes <NUM> serving as coupling holes penetrate through the first flange <NUM> at a plurality of locations (six locations in this embodiment) in a circumferential direction of the first flange <NUM>.

Subsequently, the valve device <NUM> will be described in detail.

As illustrated in <FIG>, the valve housing <NUM> of the valve device <NUM> includes a housing main body <NUM> made of metal and having a valve movement passage <NUM> which accommodates the valve body <NUM> having a plate shape and made of metal such that the valve body <NUM> is movable between a closed valve position and an open valve position, and a coupling cylinder portion <NUM> made of metal and extending to a top plate 102A of the housing main body <NUM> in a state where the coupling cylinder portion <NUM> is coaxial with the branch pipe <NUM>. An internal flow path 103B of the coupling cylinder portion <NUM> has the same inner diameter as that of the branch flow path 16B in the branch pipe <NUM>. In addition, a second flange 103A to which work equipment <NUM> or piping equipment is detachably coupled in a watertight state extends from an upper end portion of the coupling cylinder portion <NUM>. Examples of the work equipment <NUM> coupled to the second flange 103A of the coupling cylinder portion <NUM> include a drilling device <NUM> illustrated in <FIG> and <FIG> (refer to <FIG> and <FIG>), a flow path-closing device <NUM> illustrated in <FIG> (refer to <FIG>), and the like.

The second flange 103A of the coupling cylinder portion <NUM> has the same outer diameter as that of the first flange <NUM>, and coupling screw holes <NUM> serving as coupling holes are formed in the second flange 103A at a plurality of locations (six locations in this embodiment) in a circumferential direction of the second flange 103A. The first bolt insertion holes <NUM> of the first flange <NUM> and the coupling screw holes <NUM> of the second flange 103A are formed with the same pitch at the same phase positions.

An installation port portion <NUM> which is externally mountable on the first flange <NUM> of the branch pipe <NUM> from a branch axis Y direction in a detachable manner is formed in a bottom plate 102B of the housing main body <NUM>. A seal installation groove <NUM> having an annular shape is formed in an inner peripheral surface of the installation port portion <NUM>, and a seal member <NUM> such as an O-ring is installed in the seal installation groove <NUM> to seal a gap between facing surfaces of the inner peripheral surface of the installation port portion <NUM> and an outer peripheral surface of the first flange <NUM> in a watertight state.

The outer diameter of the valve body <NUM> is the same or substantially the same as the outer diameter of the first flange <NUM>, and is slightly smaller than the inner diameter of the inner peripheral surface of the installation port portion <NUM> of the housing main body <NUM>. A packing installation groove 31b, which has an annular shape and opens downward toward the ring-shaped valve seat surface <NUM> at the closed valve position where a flow path opening of the branch pipe <NUM> is blocked, is formed in a flow path-blocking surface 31a that corresponds to a lower surface side of the valve body <NUM>. The first packing <NUM> is installed in the packing installation groove 31b.

Mounting holes <NUM> are formed in portions of the valve body <NUM> at a plurality of locations (six locations in this embodiment) in a circumferential direction of the valve body <NUM>, the portions corresponding to the first bolt insertion holes <NUM> of the first flange <NUM> at the closed valve position. The mounting holes <NUM> of the valve body <NUM> and the first bolt insertion holes <NUM> of the first flange <NUM> are disposed with the same pitch at the same phase positions.

As illustrated in <FIG>, the mounting holes <NUM> of the valve body <NUM> at the closed valve position and the first bolt insertion holes <NUM> of the first flange <NUM> can be watertighly fixed and coupled to each other by bolts <NUM> and nuts <NUM> that form a first fastening portion <NUM> for the fixation of the valve.

As illustrated in <FIG> and <FIG>, mounting pieces <NUM> which protrude further downward than a lower surface of the first flange <NUM> of the branch pipe <NUM> are formed in the installation port portion <NUM> of the housing main body <NUM> at a plurality of locations (four locations in this embodiment) in a circumferential direction of the installation port portion <NUM>. A screw hole <NUM> having a screw axis at a height position that is slightly deviated below the lower surface of the first flange <NUM> of the branch pipe <NUM> penetrates through each of the mounting pieces <NUM>. A pulling bolt <NUM> including a tapered surface 122a which comes into contact with an outer peripheral edge on a lower surface side of the first flange <NUM> from outward in the radial direction is detachably screwed into each of the screw holes <NUM>.

As illustrated in <FIG>, <FIG>, and <FIG>, the screw holes <NUM> which are formed in a plurality of the mounting pieces <NUM> of the installation port portion <NUM> of the housing main body <NUM>, and the pulling bolts <NUM> which are screwed into the screw holes <NUM> form a second fastening portion <NUM> by which the valve housing <NUM> of the valve device <NUM> is pulled toward and fixed to the first flange <NUM> of the branch pipe <NUM> in a watertight state.

Inside the housing main body <NUM>, a rotary arm <NUM> which is rotationally operable around an axis parallel to or substantially parallel to the flow path axis of the connection port portion 16A of the branch pipe <NUM> is disposed, and a linkage mechanism <NUM> which causes the valve body <NUM> to reciprocate between the closed valve position and the open valve position in conjunction with the rotation of the rotary arm <NUM> is provided. The linkage mechanism <NUM> can be changed between a linked state and a non-linked state in the branch axis Y direction, and is configured to be changed to the non-linked state as the valve housing <NUM> moves in the branch axis Y direction to separate from (remove from) the valve body <NUM> fixed to the connection port portion 16A of the branch pipe <NUM>.

Subsequently, a specific configuration of the switching operation portion of the valve body <NUM> will be described.

As illustrated in <FIG>, an opening <NUM> through which the rotary arm <NUM> can be inserted into and disposed in the valve movement passage <NUM> is formed in the top plate 102A of the housing main body <NUM>. A lid plate <NUM> which closes the opening <NUM> is provided with a boss portion <NUM> that rotatably supports a rotary shaft <NUM> in a state where the rotary shaft <NUM> parallel to or substantially parallel to the flow path axis of the connection port portion 16A penetrates through the boss portion <NUM>. A base end portion of the rotary arm <NUM> is fixed to a lower end shaft portion of the rotary shaft <NUM> supported by the boss portion <NUM>, and a handle <NUM> is installed on an upper end shaft portion of the rotary shaft <NUM>. In addition, seal members <NUM> such as O-rings are installed in ring-shaped seal installation grooves, which are formed in an intermediate shaft portion of the rotary shaft <NUM> at two locations, to seal a gap between the intermediate shaft portion and an inner peripheral surface of the boss portion <NUM> in a watertight state.

The linkage mechanism <NUM> includes an elongated hole <NUM> that is formed in a base end portion of the valve body <NUM> on an upstream side in a valve closing direction (end portion that is spaced apart from the flow path opening of the branch pipe <NUM>), and an engagement protrusion <NUM> that is provided in a tip portion of the rotary arm <NUM>. The engagement protrusion <NUM> of the rotary arm <NUM> is configured to be able to engage with the elongated hole <NUM> of the valve body <NUM> from above and disengage therefrom. For this reason, as the valve housing <NUM> moves upward to separate from the valve body <NUM> fixed to the connection port portion 16A of the branch pipe <NUM>, the engagement protrusion <NUM> of the rotary arm <NUM> assembled to the valve housing <NUM> is pulled upward out from the elongated hole <NUM> of the valve body <NUM>. Accordingly, the state of connection between the engagement protrusion <NUM> of the rotary arm <NUM> and the elongated hole <NUM> of the valve body <NUM> is changed from a linked state to a non-linked state.

As illustrated in <FIG>, the elongated hole <NUM> of the valve body <NUM> is formed along a direction orthogonal to a valve movement direction (valve passage width direction of the valve movement passage <NUM>), and the central position of the elongated hole <NUM> in a longitudinal direction of the elongated hole <NUM> is also used as that of the mounting hole <NUM> into which the bolt <NUM> of the first fastening portion <NUM> is inserted, the bolt <NUM> having a larger diameter than that of the engagement protrusion <NUM>. For this reason, as illustrated in <FIG>, of both inner surfaces 138a and 138b of the elongated hole <NUM> in the valve movement direction, the inner surface 138b which is positioned outward in the radial direction of the valve body <NUM> is curved into a flat "V" shape where the inner surface 138b stretches outward as a central position side of the elongated hole <NUM> in the longitudinal direction is approached. In addition, the lid plate <NUM> is detachably fixed to a peripheral edge of the opening <NUM> in the top plate 102A of the housing main body <NUM> in a watertight state by bolts.

As illustrated in <FIG> and <FIG>, a linear guide portion <NUM> which guides the valve body <NUM> to move in a non-rotatable state between the closed valve position and the open valve position in a linear direction is provided on an inner surface side of the valve housing <NUM>. The linear guide portion <NUM> includes a pair of guide rails <NUM> along the valve movement direction which are firmly fixed to an inner surface of the top plate 102A of the housing main body <NUM>, and guide pins <NUM> that are provided on an upper surface of the valve body <NUM> in a state where the guide pins <NUM> are slidably in contact with both guide rails <NUM>. The interval between the both guide rails <NUM> in the valve passage width direction is larger than the inner diameter of the installation port portion <NUM> of the housing main body <NUM>, and is smaller than the interval between both mounting holes <NUM> that face each other in the valve passage width direction. In addition, a region between the both guide rails <NUM> is formed as an operation space of the rotary arm <NUM>.

The guide pins <NUM> are provided at a total of four locations, namely, in both side portions of a tip portion of the valve body <NUM> in the valve passage width direction and both side portions of the base end portion of the valve body <NUM> in the valve passage width direction. In a state where the rotation of the valve body <NUM> is prevented, the valve body <NUM> is guided to move in the linear direction by slide contact between the guide pins <NUM> and the both guide rails <NUM>.

As illustrated in <FIG> and <FIG>, the housing main body <NUM> is provided with a valve body-pressing portion <NUM> that presses the first packing <NUM> of the valve body <NUM> at the closed valve position against the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM> in a watertight state. The valve body-pressing portion <NUM> includes female screw members <NUM> that are firmly fixed to both side portions in the top plate 102A of the housing main body <NUM> with respect to a center line in the valve passage width direction, the center line passing through the flow path axis of the connection port portion 16A, in a state where the female screw members <NUM> penetrate through the both side portions, and push bolts <NUM> which can be screwed into the female screw members <NUM> from above and of which each has a length to be able to press the upper surface of the valve body <NUM> at the closed valve position.

A seal member <NUM> such as an O-ring is installed on an inner peripheral surface of each of the female screw members <NUM> to seal a gap between the inner peripheral surface and an outer peripheral surface of the push bolt <NUM> in a watertight state.

As illustrated in <FIG> and <FIG>, bolt insertion holes 102a through which the bolts <NUM> of the first fastening portion <NUM> for fixing the valve are inserted into the housing main body <NUM> are formed in portions of the top plate 102A of the housing main body <NUM> along the circumferential direction, the portions corresponding to the mounting holes <NUM> of the valve body <NUM> at the closed valve position, while penetrating through the portions. When the valve body <NUM> is not fixed to the first flange <NUM>, a first hole closing tool <NUM> which has a split structure and closes all of the bolt insertion holes 102a in a watertight state so as to prevent the fluid from flowing out from the bolt insertion holes 102a is detachably mounted on the valve housing <NUM>.

As illustrated in <FIG> and <FIG>, the first hole closing tool <NUM> includes a pair of first closing support plates <NUM> of which each has a semi-annular shape and which can be disposed along the bolt insertion holes 102a of the top plate 102A of the housing main body <NUM>. First plug members <NUM> that are detachably fitted into a plurality of (three in this embodiment) of the bolt insertion holes 102a from above which are positioned in a semi-circular region are firmly fixed to each of the both first closing support plates <NUM>. A seal member <NUM> such as an O-ring is installed on each of the first plug members <NUM> to seal a gap between the first plug member <NUM> and an inner peripheral surface of the bolt insertion hole 102a in a watertight state. The first plug member <NUM> on which the seal member <NUM> is installed forms a sealing and closing portion that closes the bolt insertion hole 102a of the top plate 102A of the housing main body <NUM> in a watertight state.

As illustrated in <FIG>, a first screw shaft <NUM> protruding upward is formed in the first plug member <NUM> that is disposed in a central portion of each of the first closing support plates <NUM> in a semi-circumferential direction. A first long nut <NUM> having a hexagonal shape and capable of coming into contact with a lower surface of the second flange 103A of the coupling cylinder portion <NUM> is screwed onto the first screw shaft <NUM>. A first positioning recess <NUM> which has a circular shape and into which an upper end portion of the first long nut <NUM> is rotatably fitted is formed in the lower surface of the second flange 103A of the coupling cylinder portion <NUM>.

Then, when the first hole closing tool <NUM> is mounted, the first plug members <NUM> of the first closing support plate <NUM> are disposed at positions immediately above the bolt insertion holes 102a of the top plate 102A of the housing main body <NUM>. In addition, the upper end portion of the first long nut <NUM> which is screwed onto the first screw shaft <NUM> of the first plug member <NUM> positioned in the central portion is fitted and disposed in the first positioning recess <NUM> of the lower surface of the second flange 103A of the coupling cylinder portion <NUM>. In this state, when the first long nut <NUM> is rotationally operated to a tension side where the distance between the first long nut <NUM> and the first closing support plate <NUM> increases, the seal member <NUM> installed on each of the first plug members <NUM> is press-fitted into the bolt insertion hole 102a, so that the bolt insertion hole 102a is closed in a watertight state. When the first long nut <NUM> is further rotationally operated to the tension side, the first closing support plate <NUM> is pressed against the upper surface of the top plate 102A of the housing main body <NUM>, and the first hole closing tool <NUM> is fixed in a tension state between the lower surface of the second flange 103A of the coupling cylinder portion <NUM> and the upper surface of the top plate 102A of the housing main body <NUM>.

As illustrated in <FIG> and <FIG>, when the valve body <NUM> is not fixed to the first flange <NUM> of the branch pipe <NUM>, a second hole closing tool <NUM> which has a split structure and closes all of the first bolt insertion holes <NUM> in a watertight state so as to prevent the fluid from flowing out from the first bolt insertion holes <NUM> of the first flange <NUM> is detachably mounted on the split T-shaped pipe <NUM>.

As illustrated in <FIG> and <FIG>, the second hole closing tool <NUM> includes a pair of second closing support plates <NUM> of which each has a semi-annular shape and which can be disposed along the first bolt insertion holes <NUM> of the first flange <NUM>. Second plug members <NUM> that are detachably fitted into a plurality of (three in this embodiment) of the first bolt insertion holes <NUM> from below which are positioned in a semi-circular region are firmly fixed to each of the both second closing support plates <NUM>. A seal member <NUM> such as an O-ring is installed on each of the second plug members <NUM> to seal a gap between the second plug member <NUM> and an inner peripheral surface of the first bolt insertion hole <NUM> in a watertight. The second plug member <NUM> on which the seal member <NUM> is installed forms a sealing and closing portion that closes the first bolt insertion hole <NUM> of the first flange <NUM> in a watertight state.

As illustrated in <FIG>, a second screw shaft <NUM> protruding downward is formed in the second plug member <NUM> that is disposed in a central portion of each of the second closing support plates <NUM> in a semi-circumferential direction. A second long nut <NUM> having a hexagonal shape and capable of coming into contact with a top side of the split coupler <NUM> positioned uppermost is screwed onto the second screw shaft <NUM>. A lower end portion of the second long nut <NUM> is disposed above the top of the split coupler <NUM> positioned uppermost with a support base <NUM> interposed therebetween. As illustrated in <FIG> and <FIG>, a second positioning recess 186a which has a circular shape and into which the lower end portion of the second long nut <NUM> is rotatably fitted is formed in an upper surface of the support base <NUM>. A recess 186b that is fitted on a rib 11B from above which is formed at the top of the split coupler <NUM> along the pipe axis direction is formed in a lower surface of the support base <NUM>.

Then, when the second hole closing tool <NUM> is mounted, the second plug members <NUM> of the second closing support plate <NUM> are disposed at positions immediately below the first bolt insertion holes <NUM> of the first flange <NUM>. In addition, the lower end portion of the second long nut <NUM> which is screwed onto the second screw shaft <NUM> of the second plug member <NUM> positioned in the central portion is fitted and disposed in the second positioning recess 186a of the support base <NUM> that is fitted and installed on the rib 11B of the split coupler <NUM>. In this state, when the second long nut <NUM> is rotationally operated to a tension side where the distance between the second long nut <NUM> and the second closing support plate <NUM> increases, the seal member <NUM> installed on each of the second plug members <NUM> is press-fitted into the first bolt insertion hole <NUM>, so that the first bolt insertion hole <NUM> is closed in a watertight state. When the second long nut <NUM> is further rotationally operated to the tension side, the second closing support plate <NUM> is pressed against the lower surface of the first flange <NUM>, and the second hole closing tool <NUM> is fixed in a tension state between the lower surface of the first flange <NUM> of the branch pipe <NUM> and the top of the split coupler <NUM> positioned uppermost.

The outer diameter of an outer peripheral side surface of each of the both the second closing support plates <NUM> is larger than the outer diameter of the first flange <NUM>. Protrusion portions of the both second closing support plates <NUM> which protrude further outward in the radial direction than the outer peripheral surface of the first flange <NUM> form a load receiving portion <NUM> on which a lower end surface of the installation port portion <NUM> of the valve housing <NUM> is placed and supported. Then, in a state where the lower end surface of the installation port portion <NUM> of the valve housing <NUM> is placed and supported on the load receiving portion <NUM>, a sliding guide surface 102b which corresponds to an inner surface side of the bottom plate 102B of the housing main body <NUM> and guides the sliding of the first packing <NUM> of the valve body <NUM>, and the ring-shaped valve seat surface <NUM> of the connection port portion 16A on which the first packing <NUM> of the valve body <NUM> slides are disposed at the same or substantially the same height position.

In addition, as illustrated in <FIG>, when the lower end surface of the installation port portion <NUM> of the valve housing <NUM> is placed and supported on the load receiving portion <NUM> of the both second closing support plates <NUM>, cutout portions 181a of which each has the shape of a recess and through which the plurality of mounting pieces <NUM> of the installation port portion <NUM> of the housing main body <NUM> pass are formed in the both second closing support plates <NUM>. The tapered surface 122a of the pulling bolt <NUM> screwed into the screw hole <NUM> of the mounting piece <NUM> engages with the outer peripheral edge on the lower surface side of the first flange <NUM> which is present in the cutout portions 181a of the both second closing support plates <NUM>.

In a case where the work equipment <NUM> is the drilling device <NUM>, as illustrated in <FIG> and <FIG> (refer to <FIG> and <FIG>), a third flange 82A of a short pipe <NUM> coupled to a drilling drive case <NUM> is coupled to the second flange 103A of the coupling cylinder portion <NUM> of the valve housing <NUM> in a watertight state. In a state where the third flange 82A of the short pipe <NUM> is coupled to the second flange 103A of the coupling cylinder portion <NUM>, a drive rotary shaft <NUM> of the drilling device <NUM> is present in an internal space of the coupling cylinder portion <NUM>, and a rotary cutting tool <NUM> is mounted on a tip portion of the drive rotary shaft <NUM>. The rotary cutting tool <NUM> includes a hole saw <NUM> having a cylindrical shape and including a cutting tip, and a center drill <NUM> that protrudes toward a tip side from a rotation center position inside the hole saw <NUM>. The rotary cutting tool <NUM> of the drilling device <NUM> corresponds to a work portion <NUM> of the work equipment <NUM>.

In a case where the work equipment <NUM> is the flow path-closing device <NUM>, as illustrated in <FIG> (refer to <FIG>), a fourth flange 91A of a closing case <NUM> is coupled to the second flange 103A of the coupling cylinder portion <NUM> of the valve housing <NUM> in a watertight state. In a state where the fourth flange 91A of the closing case <NUM> is coupled to the second flange 103A of the coupling cylinder portion <NUM>, a closing bag <NUM> which is one example of a closing work portion accommodated in the closing case <NUM> and is accommodated in a reduced state is present in the internal space of the coupling cylinder portion <NUM>. The closing bag <NUM> of the flow path-closing device <NUM> corresponds to the work portion <NUM> of the work equipment <NUM>.

While maintaining a watertight state with respect to the closing case <NUM>, the closing bag <NUM> is mounted on a tip portion of an operation cylinder shaft <NUM> which penetrates through the closing case <NUM> from outside and is supported to be movable along a branch axis direction. A fluid for diameter expansion is supplied into the closing bag <NUM> from a supply and discharge flow path 93a (refer to <FIG>) inside the operation cylinder shaft <NUM>, so that the closing bag <NUM> inflates to a state where an in-pipe flow path inside the fluid pipe <NUM> (refer to <FIG>) can be closed.

In addition, the closing bag <NUM> is accommodated inside an insertion guide cylinder body <NUM> that is movable in the branch axis direction along an inner surface of the closing case <NUM>, an inner surface of the coupling cylinder portion <NUM> of the valve housing <NUM>, and an inner surface of the branch pipe <NUM>. The insertion guide cylinder body <NUM> integrally moves together with the closing bag <NUM> as the operation cylinder shaft <NUM> is delivered inward, and the insertion guide cylinder body <NUM> comes into contact with an opening peripheral edge on an outer peripheral surface side of a through-hole <NUM>, which is formed in the fluid pipe <NUM>, to stop. In this state, when the operation cylinder shaft <NUM> is delivered further inward, the closing bag <NUM> is pulled out from the insertion guide cylinder body <NUM>, and the closing bag <NUM> is inserted into the in-pipe flow path from the through-hole <NUM> of the fluid pipe <NUM>.

In this embodiment, the valve device <NUM> configured as described above is used in a renewal work where the fluid pipe <NUM> forming a pipeline structure or piping equipment such as a fire hydrant is renewed without flow disruption, or an earthquake resistance work where piping equipment for earthquake resistance is replaced without flow disruption.

Subsequently, a method of a renewal and earthquake resistance work including a valve removal method of a fluid pipeline structure will be described.

As illustrated in <FIG>, a split T-shaped pipe mounting step of externally mounting and fixing the split T-shaped pipe <NUM> having a split structure and including the branch pipe <NUM> on a portion upstream of a work target region of the fluid pipe <NUM> in a watertight state is executed.

In the split T-shaped pipe mounting step, the split couplers <NUM> which are three split elements of the split T-shaped pipe <NUM> are externally mounted on the fluid pipe <NUM>, and the coupling flange portions 11A of both split couplers <NUM> adjacent to each other are tightened and fixed to each other in a watertight state by the bolts <NUM> and the nuts <NUM>.

As illustrated in <FIG> and <FIG>, a valve device mounting step of mounting the valve device <NUM> on the branch pipe <NUM> of the split T-shaped pipe <NUM> in a watertight state is executed.

The valve device mounting step includes a housing-exterior mounting step of externally mounting the valve housing <NUM> of the valve device <NUM> on the first flange <NUM>, which is provided in the connection port portion 16A of the branch pipe <NUM>, from the branch axis Y direction, and a pulling and fixing step of pulling the valve housing <NUM> toward the first flange <NUM> of the branch pipe <NUM> by the pulling bolt <NUM> of the second fastening portion <NUM> provided in the valve housing <NUM>, and fixing the valve housing <NUM> to the first flange <NUM> in a watertight state in a sealed manner.

In the housing-exterior mounting step, the installation port portion <NUM> of the housing main body <NUM> forming the valve housing <NUM> of the valve device <NUM> is externally fitted and installed on the first flange <NUM> of the branch pipe <NUM> from the branch axis Y direction.

In this externally fitting and installation state, the lower end surface of the installation port portion <NUM> of the valve housing <NUM> is placed and supported on the load receiving portion <NUM> formed by the protrusion portions of the both second closing support plates <NUM> of the second hole closing tool <NUM> to be described later. In this placement and support state, the sliding guide surface 102b which corresponds to the inner surface side of the bottom plate 102B of the housing main body <NUM> and guides the sliding of the first packing <NUM> of the valve body <NUM>, and the ring-shaped valve seat surface <NUM> of the connection port portion 16A on which the first packing <NUM> of the valve body <NUM> slides are disposed at the same or substantially the same height position. Accordingly, the opening and closing operation of the valve body <NUM> can be smoothly performed. Moreover, since the load receiving portion <NUM> is configured to be attachable to and detachable from the branch pipe <NUM> of the split T-shaped pipe <NUM>, it is not required that the split T-shaped pipe <NUM> which is large and includes the branch pipe <NUM> is remade as when the load receiving portion <NUM> is formed integrally with the first flange <NUM> of the branch pipe <NUM>; and thereby, it is possible to securely and easily install the valve housing <NUM> on the first flange <NUM> of the branch pipe <NUM> which is existing while reducing the initial investment.

In the pulling and fixing step, as illustrated in <FIG> and <FIG>, the pulling bolts <NUM> are screwed into the screw holes <NUM> of the mounting pieces <NUM> that are formed in the installation port portion <NUM> of the housing main body <NUM> at the plurality of locations in the circumferential direction. The tapered surfaces 122a of the pulling bolts <NUM> come into contact with the outer peripheral edge on the lower surface side of the first flange <NUM> from outward in the radial direction, and as the pulling bolts <NUM> are tightened, the valve housing <NUM> of the valve device <NUM> is pulled toward and fixed to a connection port portion 16A side of the branch pipe <NUM>. Due to the pulling and fixing, as illustrated in <FIG>, the seal member <NUM> which is installed in the seal installation groove <NUM> of the inner peripheral surface of the installation port portion <NUM> is compressed in a watertight state by the outer peripheral surface of the first flange <NUM>.

As illustrated in <FIG>, the foregoing valve device mounting step includes a step of mounting the first hole closing tool <NUM> that prevents the fluid from flowing out from the bolt insertion holes 102a penetrating through the top plate 102A of the housing main body <NUM>. In the first hole closing tool mounting step, the first plug members <NUM> of the first closing support plates <NUM> forming the first hole closing tool <NUM> are disposed at the positions immediately above the bolt insertion holes 102a of the top plate 102A of the housing main body <NUM>. In addition, the first long nut <NUM> is screwed onto the first screw shaft <NUM> of the first plug member <NUM> that is positioned in the central portion of the first closing support plate <NUM>, and the upper end portion of the first long nut <NUM> is fitted and installed into the first positioning recess <NUM> of the lower surface of the second flange 103A of the coupling cylinder portion <NUM>. In this state, when the first long nut <NUM> is rotationally operated to a tension side where the distance between the first long nut <NUM> and the first closing support plate <NUM> increases, the seal member <NUM> installed on each of the first plug members <NUM> is press-fitted into the bolt insertion hole 102a, so that the bolt insertion hole 102a is closed in a watertight state. When the first long nut <NUM> is further rotationally operated to the tension side, the first closing support plate <NUM> is pressed against the upper surface of the top plate 102A of the housing main body <NUM>, and the first hole closing tool <NUM> is fixed in a tension state between the lower surface of the second flange 103A of the coupling cylinder portion <NUM> and the upper surface of the top plate 102A of the housing main body <NUM>.

As illustrated in <FIG>, the foregoing valve device mounting step includes a step of mounting the second hole closing tool <NUM> that prevents the fluid from flowing out from each of the first bolt insertion holes <NUM> which are formed in the first flange <NUM> of the branch pipe <NUM>. In the second hole closing tool mounting step, the second plug members <NUM> of the second closing support plates <NUM> forming the second hole closing tool <NUM> are disposed at the positions immediately below the first bolt insertion holes <NUM> of the first flange <NUM>. In addition, the second long nut <NUM> is screwed onto the second screw shaft <NUM> of the second plug member <NUM> that is positioned in the central portion of the second closing support plate <NUM>, and the lower end portion of the second long nut <NUM> is fitted and installed into the second positioning recess 186a of the support base <NUM> that is fitted and installed on the rib 11B of the split coupler <NUM>. In this state, when the second long nut <NUM> is rotationally operated to a tension side where the distance between the second long nut <NUM> and the second closing support plate <NUM> increases, the seal member <NUM> installed on each of the second plug members <NUM> is press-fitted into the first bolt insertion hole <NUM>, so that the first bolt insertion hole <NUM> is closed in a watertight state. When the second long nut <NUM> is further rotationally operated to the tension side, the second closing support plate <NUM> is pressed against the lower surface of the first flange <NUM>, and the second hole closing tool <NUM> is fixed in a tension state between the lower surface of the first flange <NUM> of the branch pipe <NUM> and the top of the split coupler <NUM> positioned uppermost.

Furthermore, the foregoing valve device mounting step includes an open valve setting step of setting the valve body <NUM> of the valve device <NUM> to the open valve position as illustrated in <FIG> and <FIG>, and a valve-pressing release setting step of setting the valve body-pressing portion <NUM> to a valve-pressing release setting state as illustrated in <FIG>. In the open valve setting step, as illustrated in <FIG> and <FIG>, the valve body <NUM> is set to the open valve position where the elongated hole <NUM> of the valve body <NUM> is most spaced apart from the branch flow path 16B of the branch pipe <NUM>. In addition, in the valve-pressing release setting step, as illustrated in <FIG>, the push bolt <NUM> which is screwed into the female screw member <NUM> of the top plate 102A of the housing main body <NUM> is set to a pressing release position where the push bolt <NUM> is spaced apart from the upper surface of the valve body <NUM>.

As illustrated in <FIG>, a drilling device mounting step (one example of a work equipment mounting step) of mounting the drilling device <NUM> which is one example of the work equipment <NUM> on the valve device <NUM> is executed. In detail, the third flange 82A of the short pipe <NUM> coupled to the drilling drive case <NUM> of the drilling device <NUM> is tightened and fixed to the second flange 103A of the coupling cylinder portion <NUM> of a housing main body <NUM> in a watertight state by bolts <NUM>, which are screwed into the coupling screw holes <NUM> of the second flange 103A, and nuts <NUM>.

When the drilling device <NUM> is mounted, since the through-hole <NUM> (refer to <FIG>) is not formed in the fluid pipe <NUM>, the valve body <NUM> of the valve device <NUM> is held at the open valve position.

As illustrated in <FIG> and <FIG>, a drilling work step (one example of a predetermined work step) of performing a drilling work (one example of a predetermined work) where the rotary cutting tool <NUM> of the drilling device <NUM> is delivered inward toward a fluid pipe <NUM> side (refer to <FIG>) which is a work target portion upstream of the branch pipe <NUM> and the through-hole <NUM> is formed in a pipe wall of the fluid pipe <NUM> is executed.

In the drilling work step, the virtual line in <FIG> illustrates a state where the rotary cutting tool <NUM> of the drilling device <NUM> is delivered into the branch pipe <NUM> of the split T-shaped pipe <NUM>, and <FIG> illustrates a state where after the drilling work is performed, the rotary cutting tool <NUM> holding a cut piece 1a of the pipe wall moves to return to an initial position above (downstream of) the valve body <NUM> inside the housing main body <NUM>.

A drilling device removing step (one example of a work equipment removing step) of removing the drilling device <NUM> from the valve device <NUM> after the valve body <NUM> of the valve device <NUM> is operated to the closed valve position is executed. In the drilling device removing step, the bolt coupling between the second flange 103A of the coupling cylinder portion <NUM> of the housing main body <NUM> and the third flange 82A of the short pipe <NUM> of the drilling device <NUM> is released, and the drilling device <NUM> is removed from the valve device <NUM>.

In addition, when the valve body <NUM> of the valve device <NUM> is operated to the closed valve position, the push bolts <NUM> which are screwed into the female screw members <NUM> of the top plate 102A of the housing main body <NUM> are screwed to a tightening side to press the upper surface of the valve body <NUM> at the closed valve position. Accordingly, the first packing <NUM> of the flow path-blocking surface 31a of the valve body <NUM> is maintained in a watertight state where the first packing <NUM> is crimped by the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM>.

As illustrated in <FIG>, a flow path-closing device mounting step (one example of a work equipment mounting step) of mounting the flow path-closing device <NUM> which is one example of the work equipment <NUM> on the valve device <NUM> is executed.

In the flow path-closing device mounting step, the fourth flange 91A of the closing case <NUM> of the flow path-closing device <NUM> is tightened and fixed to the second flange 103A of the coupling cylinder portion <NUM> of the housing main body <NUM> in a watertight state by the bolts <NUM>, which are screwed into the coupling screw holes <NUM> of the second flange 103A, and the nuts <NUM>. In this coupling state, the closing bag <NUM> in a reduced state, which is one example of the closing work portion and is accommodated in the closing case <NUM>, faces the internal flow path 103B of the coupling cylinder portion <NUM>.

As illustrated in <FIG>, a flow path closing work step (one example of a predetermined work step) of operating the valve body <NUM> of the valve device <NUM> to the open valve position and delivering the closing bag <NUM> of the flow path-closing device <NUM> into the fluid pipe <NUM> (refer to <FIG>) which is a closing work target portion on the upstream side to close the in-pipe flow path is executed.

In the flow path closing work step, before the valve body <NUM> of the valve device <NUM> is operated to the open valve position, the push bolts <NUM> of the valve body-pressing portions <NUM> are rotationally operated to the pressing release position where the push bolts <NUM> are spaced apart from the upper surface of the valve body <NUM>.

Subsequently, after the valve body <NUM> is operated to the open valve position, the operation cylinder shaft <NUM> is delivered inward from outside the closing case <NUM>, and the insertion guide cylinder body <NUM> and the closing bag <NUM> are integrally delivered inward. Thereafter, the insertion guide cylinder body <NUM> comes into contact with the opening peripheral edge of the through-hole <NUM> in an outer peripheral surface of the fluid pipe <NUM> to stop. In this state, when the operation cylinder shaft <NUM> is delivered further inward, the closing bag <NUM> is pulled out from the insertion guide cylinder body <NUM>, and the closing bag <NUM> is inserted into a predetermined close position in the in-pipe flow path from the through-hole <NUM> of the fluid pipe <NUM>. In this state, the fluid for diameter expansion is supplied into the closing bag <NUM> from the supply and discharge flow path 93a (refer to <FIG>) inside the operation cylinder shaft <NUM>, so that the closing bag <NUM> inflates to a state where the in-pipe flow path inside the fluid pipe <NUM> is closed.

Then, when the in-pipe flow path inside the fluid pipe <NUM> is closed by the closing bag <NUM> of the flow path-closing device <NUM>, in a work target region downstream of the close position, a predetermined work such as a renewal work where the fluid pipe <NUM> forming a pipeline structure or piping equipment such as a fire hydrant is renewed without water disruption, or an earthquake resistance work where piping equipment for earthquake resistance is replaced without water disruption is performed.

As illustrated in <FIG>, a flow path-closing device removing step (one example of the work equipment removing step) of removing the flow path-closing device <NUM> from the valve device <NUM> after the valve body <NUM> of the valve device <NUM> is operated to the closed valve position is executed.

In the flow path-closing device removing step, when the predetermined work is finished, the fluid for diameter expansion in the closing bag <NUM> which closes the in-pipe flow path inside the fluid pipe <NUM> is discharged from the supply and discharge flow path 93a (refer to <FIG>) inside the operation cylinder shaft <NUM>, so that the closing bag <NUM> is brought into a contracted state where the diameter thereof is reduced. In this state, the operation cylinder shaft <NUM> returns upward, so that the closing bag <NUM> and the insertion guide cylinder body <NUM> are accommodated in the closing case <NUM>.

Subsequently, as illustrated in <FIG>, after the valve body <NUM> is operated to the closed valve position, the push bolts <NUM> which are screwed into the female screw members <NUM> of the top plate 102A of the housing main body <NUM> are screwed to a tightening side, so that the first packing <NUM> of the flow path-blocking surface 31a of the valve body <NUM> is maintained in a watertight state where the first packing <NUM> is crimped by the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM>. Thereafter, the bolt coupling between the second flange 103A of the coupling cylinder portion <NUM> of the housing main body <NUM> and the fourth flange 91A of the closing case <NUM> is released, and the flow path-closing device <NUM> is removed from the valve device <NUM>.

After the flow path-closing device removing step is finished, the procedure proceeds to the valve removal method.

As illustrated on the left side of <FIG>, a valve body fixing step of fixing the valve body <NUM> at the closed valve position to the first flange <NUM> of the branch pipe <NUM> in a watertight state in a sealed manner includes a step of removing the first hole closing tool <NUM> that prevents the fluid from flowing out form the bolt insertion holes 102a of the top plate 102A of the housing main body <NUM>, a step of removing the second hole closing tool <NUM> that prevents the fluid from flowing out from the first bolt insertion holes <NUM> of the first flange <NUM>, and a valve body fixing and coupling step of fixing and coupling the valve body <NUM> at the closed valve position and the first flange <NUM> of the branch pipe <NUM> to each other in a watertight state by the bolt <NUM> and the nut <NUM> of the first fastening portion <NUM>.

In the first hole closing tool removing step, when the first long nuts <NUM> of the first hole closing tool <NUM> are rotationally operated to a loose side, the tension state of the first hole closing tool <NUM> which is fixed between the lower surface of the second flange 103A of the coupling cylinder portion <NUM> and the upper surface of the top plate 102A of the housing main body <NUM> is released. Accordingly, the upper end portions of the first long nuts <NUM> separate from the first positioning recesses <NUM> of the lower surface of the second flange 103A of the coupling cylinder portion <NUM>. In this separation state, the first plug members <NUM> of the first closing support plates <NUM> are pulled out from the bolt insertion holes 102a of the top plate 102A, and the first hole closing tool <NUM> is removed.

In the second hole closing tool removing step, when the second long nuts <NUM> of the second hole closing tool <NUM> are rotationally operated to a loose side, the tension state of the second hole closing tool <NUM> which is fixed between the lower surface of the first flange <NUM> of the branch pipe <NUM> and the top of the split coupler <NUM> positioned uppermost is released. Accordingly, the lower end portions of the second long nuts <NUM> separate from the second positioning recesses 186a of the support bases <NUM>, and the support bases <NUM> are removed from the ribs 11B of the split coupler <NUM>. Subsequently, the second plug members <NUM> of the second closing support plates <NUM> are pulled out from the first bolt insertion holes <NUM> of the first flange <NUM>, and the second hole closing tool <NUM> is removed.

In the valve body fixing and coupling step, the bolts <NUM> are inserted into the first bolt insertion holes <NUM> of the first flange <NUM> of the branch pipe <NUM> from below, and the nuts <NUM> are inserted into the bolt insertion holes 102a of the top plate 102A of the housing main body <NUM> from above. The valve body <NUM> at the closed valve position and the first flange <NUM> of the branch pipe <NUM> are fixed and coupled to each other in a watertight state by fastening the bolts <NUM> and the nuts <NUM> by screwing.

As illustrated in <FIG> and <FIG>, a valve component removing step of removing other unnecessary valve components while the valve body <NUM> fixed to the first flange <NUM> of the branch pipe <NUM> is left on the first flange <NUM> of the branch pipe <NUM> is executed.

In the valve component removing step, as illustrated in <FIG>, the pulling bolts <NUM> are screwed to a loose side with respect to the screw holes <NUM> of the mounting pieces <NUM> that are formed in the installation port portion <NUM> of the housing main body <NUM> at the plurality of locations in the circumferential direction. Accordingly, the tapered surfaces 122a of the pulling bolts <NUM> separate outward in the radial direction from the outer peripheral edge on the lower surface side of the first flange <NUM>. In this state, the installation port portion <NUM> of the valve housing <NUM> is removed from the first flange <NUM> of the branch pipe <NUM>; and thereby, it is also possible to simultaneously remove the other unnecessary valve components that are integrally assembled with the valve housing <NUM>. Therefore, it is possible to efficiently and easily perform the work of removing the other valve components including the valve housing <NUM>.

The valve body <NUM> has a smaller outer diameter than the inner diameter of the installation port portion <NUM> of the valve housing <NUM>, and is coaxially fixed to the first flange <NUM> of the branch pipe <NUM> in a watertight state in a sealed manner. For this reason, when the valve housing <NUM> is removed, the valve housing <NUM> can be easily pulled out along the branch axis Y direction without a peripheral edge of the installation port portion <NUM> of the valve housing <NUM> being caught by an outer peripheral edge of the valve body <NUM>. Therefore, it is possible to more efficiently and easily perform the work of removing the other unnecessary valve components.

<FIG> illustrates a first example of the linkage mechanism <NUM> that causes the valve body <NUM> to reciprocate between the closed valve position and the open valve position in conjunction with the rotation of the rotary arm <NUM> in the first embodiment. In the first example, the both inner surfaces 138a and 138b in the elongated hole <NUM> of the valve body <NUM> in the valve movement direction, the elongated hole <NUM> forming one of the linkage mechanism <NUM>, are formed in a parallel or substantially parallel posture along the valve passage width direction of the valve movement passage <NUM>.

Similar to the first embodiment, the engagement protrusion <NUM> of the rotary arm <NUM> disengageably engages with the elongated hole <NUM> of the valve body <NUM> from above, and is disposed therein. For this reason, as the valve housing <NUM> moves upward to separate from the valve body <NUM> fixed to the connection port portion 16A of the branch pipe <NUM>, the engagement protrusion <NUM> of the rotary arm <NUM> assembled to the valve housing <NUM> is pulled upward out from the elongated hole <NUM> of the valve body <NUM>. Accordingly, the state of connection between the engagement protrusion <NUM> of the rotary arm <NUM> and the elongated hole <NUM> of the valve body <NUM> is changed from a linked state to a non-linked state.

In addition, as described above, since the both inner surfaces 138a and 138b of the elongated hole <NUM> of the valve body <NUM> are in a parallel or substantially parallel posture, even when the engagement protrusion <NUM> of the rotary arm <NUM> rotates to either of the closed valve position and the open valve position, slide between the engagement protrusion <NUM> and the both inner surfaces 138a and 138b of the elongated hole <NUM> is smooth; and thereby, it is possible to smoothly perform the opening and closing operation of the valve body <NUM>.

Incidentally, since other configurations are the same as those described in the first embodiment, the same reference numbers as those in the first embodiments are assigned to the same components, and the descriptions thereof will be omitted.

<FIG> illustrates a second example of the linkage mechanism <NUM> that causes the valve body <NUM> to reciprocate between the closed valve position and the open valve position in conjunction with the rotation of the rotary arm <NUM> in the first embodiment. In the second example, the linkage mechanism <NUM> includes an elongated hole <NUM> that is formed in the rotary arm <NUM>, and an engagement protrusion <NUM> that is provided in a base end portion of the valve body <NUM> on an upstream side in the valve closing direction.

Also in the second example, the elongated hole <NUM> of the rotary arm <NUM> disengageably engages with the engagement protrusion <NUM> of the valve body <NUM> from above. For this reason, as the valve housing <NUM> moves upward to separate from the valve body <NUM> fixed to the connection port portion 16A of the branch pipe <NUM>, the engagement protrusion <NUM> of the rotary arm <NUM> assembled to the valve housing <NUM> is pulled upward out from the elongated hole <NUM> of the valve body <NUM>. Accordingly, the state of connection between the engagement protrusion <NUM> of the rotary arm <NUM> and the elongated hole <NUM> of the valve body <NUM> is changed from a linked state to a non-linked state.

<FIG> illustrate another embodiment of the valve device <NUM>. <FIG> illustrate a method of a renewal and earthquake resistance work including a valve removal method in a pipeline structure using the valve device <NUM> of the another embodiment.

In the split T-shaped pipe <NUM> used in the another embodiment, as illustrated in <FIG> and <FIG>, the ring-shaped valve seat surface <NUM> which has an annular shape and with which the first packing <NUM> installed on the flow path-blocking surface 31a that corresponds to the lower surface side of the valve body <NUM> of the valve device <NUM> can come into uniform or substantially uniform contact protrudes from the connection end surface 16a of the connection port portion 16A of the branch pipe <NUM>. Furthermore, as illustrated in <FIG>, the first flange <NUM> which has an annular shape and horizontally protrudes outward in the pipe radial direction is integrally formed on the outer peripheral surface of the connection port portion 16A of the branch pipe <NUM>. As illustrated in <FIG>, a pulling inclined surface 18a having an annular shape which pulls the valve housing <NUM> of the valve device <NUM> toward the connection port portion 16A side of the branch pipe <NUM> and fixes the valve housing <NUM> to the connection port portion 16A side is formed in a lower annular corner on an outer peripheral surface side of the first flange <NUM>. A packing-pressing inclined surface 18b having an annular shape and compressing a second packing <NUM>, which is installed in the valve housing <NUM> of the valve device <NUM>, in a watertight state is formed in an upper annular corner on the outer peripheral surface side of the first flange <NUM>.

Since configurations other than the foregoing configuration of the split T-shaped pipe <NUM> are the same as the configurations described in the first embodiment, the same reference numbers as those in the first embodiment are assigned to the same components, and the descriptions thereof will be omitted.

As illustrated in <FIG>, as main components, the valve device <NUM> includes the valve housing <NUM> made of metal and having an internal flow path <NUM> that communicates with the branch flow path 16B of the branch pipe <NUM> from the branch axis direction (flow path axis direction), and the valve body <NUM> made of metal which has a plate shape and opens and closes the internal flow path <NUM> from a direction orthogonal to the branch axis direction.

As illustrated in <FIG>, the valve housing <NUM> of the valve device <NUM> includes a housing main body <NUM> in which a large-diameter cylindrical portion 34A and a small-diameter cylindrical portion 34B which are coaxially disposed in the branch axis direction are formed integrally with a valve guide cylinder portion 34C that communicates with the large-diameter cylindrical portion 34A from a horizontal direction and guides the movement of the valve body <NUM> in an opening and closing direction. A valve guide case <NUM> which guides the movement of the valve body <NUM> in the opening and closing direction in collaboration with the valve guide cylinder portion 34C is detachably coupled to the valve guide cylinder portion 34C of the housing main body <NUM> in a watertight state.

Then, the valve housing <NUM> of the valve device <NUM> includes the housing main body <NUM> and the valve guide case <NUM>. A flange portion 34c of the valve guide cylinder portion 34C of the housing main body <NUM> and a flange portion 37a of the valve guide case <NUM> are detachably joined to each other in a watertight state by bolts and nuts (not illustrated).

A second flange <NUM> to which the work equipment <NUM> or piping equipment is detachably coupled in a watertight state is formed integrally with an upper end portion of the housing main body <NUM>, which is a downstream side end portion of an outer peripheral surface of the small-diameter cylindrical portion 34B. Similar to the first embodiment, examples of the work equipment <NUM> coupled to the second flange <NUM> of the housing main body <NUM> can include the drilling device <NUM> illustrated in <FIG> and <FIG>, the flow path-closing device <NUM> illustrated in <FIG>, and the like.

As illustrated in <FIG>, an installation port portion <NUM> which is externally fitted and installed on the first flange <NUM> of the branch pipe <NUM> from the branch axis direction in a detachable manner is formed in a lower end portion of the large-diameter cylindrical portion 34A of the housing main body <NUM>. An annular stepped surface 40a which is formed at an inner corner on a deep side of the installation port portion <NUM> is formed as a placement and support surface that comes into contact with the connection end surface 16a of the first flange <NUM> of the branch pipe <NUM> from the branch axis direction.

In addition, as illustrated in <FIG>, reinforcement portions <NUM> which are thick and protrude outward are formed in the large-diameter cylindrical portion 34A of the housing main body <NUM> at a plurality of locations in a circumferential direction (six locations in the circumferential direction) of the installation port portion <NUM>. A screw hole <NUM> having a screw axis at a height position which substantially corresponds to the lower surface of the first flange <NUM> of the branch pipe <NUM> penetrates through each of the reinforcement portions <NUM>. As illustrated in <FIG>, a pulling bolt <NUM> including a tapered surface 43a which comes into contact with the pulling inclined surface 18a of the first flange <NUM> from outward in the radial direction is detachably screwed into each of the screw holes <NUM>.

As illustrated in <FIG> and <FIG>, the screw hole <NUM> formed in the reinforcement portion <NUM> of the installation port portion <NUM> of the large-diameter cylindrical portion 34A, the pulling bolt <NUM> screwed into the screw hole <NUM>, and the pulling inclined surface 18a of the first flange <NUM> with which the tapered surface 43a of the pulling bolt <NUM> comes into contact form the second fastening portion <NUM> that pulls the valve housing <NUM> of the valve device <NUM> toward the first flange <NUM> of the branch pipe <NUM> and fixes the valve housing <NUM> to the first flange <NUM> in a watertight state.

As illustrated in <FIG>, the second packing <NUM> is installed on the annular stepped surface 40a positioned inward from the installation port portion <NUM> in the large-diameter cylindrical portion 34A. For this reason, as illustrated in <FIG>, when the installation port portion <NUM> of the valve housing <NUM> is externally fitted and installed on the first flange <NUM> of the branch pipe <NUM> from the branch axis direction, and in this state, the pulling bolts <NUM> which are screwed into the screw holes <NUM> of the reinforcement portions <NUM> of the housing main body <NUM> are tightened, the valve housing <NUM> of the valve device <NUM> is pulled toward the connection port portion 16A side of the branch pipe <NUM>, and the second packing <NUM> which is installed on the annular stepped surface 40a positioned inward from the installation port portion <NUM> is compressed in a watertight state between the annular stepped surface 40a and the packing-pressing inclined surface 18b of the first flange <NUM> of the branch pipe <NUM>.

Screw holes <NUM> serving as coupling holes into which valve-fixing bolts <NUM> (refer to <FIG> and <FIG>) that fix the valve body <NUM> at the closed valve position in a watertight state can be inserted are formed in the first flange <NUM> of the branch pipe <NUM> at a plurality of locations (six locations in this embodiment) in the circumferential direction. When the valve body <NUM> is not fixed to the first flange <NUM> in a sealed manner, as illustrated in <FIG>, a waterstop bolt <NUM> including a waterstop washer <NUM> is screwed into each of the screw holes <NUM> from below to prevent water from leaking from the screw hole <NUM> of the first flange <NUM>.

Furthermore, mounting holes <NUM> into which the valve-fixing bolts <NUM> (refer to <FIG> and <FIG>) can be inserted from above penetrate through the valve body <NUM> of the valve device <NUM> at a plurality of locations (six locations in this embodiment) in the circumferential direction. The mounting holes <NUM> of the valve body <NUM> and the screw holes <NUM> of the first flange <NUM> are disposed with the same pitch at the same phase positions. As illustrated in <FIG>, a tip side screw portion of the valve-fixing bolt <NUM> which is inserted into the mounting hole <NUM> of the valve body <NUM> from above and is inserted through the screw hole <NUM> of the first flange <NUM> protrudes downward from the screw hole <NUM> of the first flange <NUM>. A nut <NUM> is screwed onto the protruding screw portion on the tip side of the valve-fixing bolt <NUM>.

Then, the mounting hole <NUM> of the valve body <NUM>, the screw hole <NUM> of the first flange <NUM> of the branch pipe <NUM>, the valve-fixing bolt <NUM>, and the nut <NUM> form the first fastening portion <NUM> (refer to <FIG> and <FIG>) that fixes the valve body <NUM> to the first flange <NUM> of the branch pipe <NUM> in a watertight state in a sealed manner.

Bolt insertion holes <NUM> through which the valve-fixing bolts <NUM> are inserted into an internal space of the housing main body <NUM> as illustrated in <FIG> penetrate through an annular step portion 34D, which connects the large-diameter cylindrical portion 34A and the small-diameter cylindrical portion 34B of the housing main body <NUM> as illustrated in <FIG>, at a plurality of locations (six locations in this embodiment) in the circumferential direction which face the screw holes <NUM> of the first flange <NUM> in the branch axis direction. The bolt insertion hole <NUM> of the annular step portion 34D has a larger diameter than that of the mounting hole <NUM> of the valve body <NUM>, and the bolt insertion holes <NUM> and the mounting holes <NUM> of the valve body <NUM> at the closed valve position are disposed with the same pitch at the same phase positions. When the valve body <NUM> is not fixed to the first flange <NUM>, as illustrated in <FIG>, and <FIG>, a hole closing tool <NUM> which has a split structure and closes all of the bolt insertion holes <NUM> in a watertight state are mounted on the housing main body <NUM>.

As illustrated in <FIG>, and <FIG>, the hole closing tool <NUM> includes split closing members <NUM> that can come into contact with an outer peripheral surface of the small-diameter cylindrical portion 34B of the housing main body <NUM> and an upper surface of the annular step portion 34D and are split into a plurality of pieces of members in the circumferential direction (two pieces of members in the circumferential direction in this embodiment).

As illustrated in <FIG>, and <FIG>, each of the split closing members <NUM> is formed into the shape of a semi-arc-shaped plate which can cover a plurality of (three in this embodiment) the bolt insertion holes <NUM>, which are positioned a semi-circular region, from above. A first elastic seal member <NUM> is provided on an inner peripheral surface of each of the split closing members <NUM> to seal a gap between the inner peripheral surface thereof and the outer peripheral surface of the small-diameter cylindrical portion 34B of the housing main body <NUM> in a watertight state. A second elastic seal member <NUM> is provided on a lower surface of each of the split closing members <NUM> to seal the lower surface thereof and the upper surface of the annular step portion 34D in a watertight state. Both end portions of each of the split closing members <NUM> in the circumferential direction are provided with coupling flange portions 61A. The coupling flange portions 61A of the both split closing members <NUM>, which face each other in the circumferential direction among the coupling flange portions 61A, are detachably tightened to each other by bolts <NUM> and nuts (not illustrated), so that the both split closing members <NUM> are fixed and coupled to each other in an annular shape. Due to the fixing and coupling, the first elastic seal members <NUM> and the second elastic seal members <NUM> of the both split closing members <NUM> are compressed in a watertight state.

The valve body <NUM> has a circular shape which has a larger diameter than an outer diameter D1 (refer to <FIG>) of the ring-shaped valve seat surface <NUM> of the connection end surface 16a of the branch pipe <NUM> and has a smaller diameter than an inner diameter D2 (refer to <FIG>) of a small-diameter inner peripheral surface 34a in the large-diameter cylindrical portion 34A of the housing main body <NUM>.

In addition, as illustrated in <FIG> and <FIG>, a female screw portion 31c along the valve movement direction is integrally formed in the base end portion of the valve body <NUM> on the upstream side in the valve closing direction (end portion that is spaced apart from the flow path opening of the branch pipe <NUM>). A male screw portion 53a on a tip side of an operating member <NUM> which has a substantially T shape and opens and closes the valve body <NUM> is detachably screwed into and coupled to the female screw portion 31c. One end portion of the female screw portion 31c protrudes outward from an outer peripheral edge of the valve body <NUM> in the radial direction. For this reason, the outer dimension of the valve body <NUM> in a diameter direction, which passes through a center line of the female screw portion 31c, becomes the maximum dimension of the valve body <NUM>. When the maximum dimension of the valve body <NUM> cannot be smaller than the inner diameter D2 of the small-diameter inner peripheral surface 34a in the large-diameter cylindrical portion 34A of the housing main body <NUM>, or the maximum dimension of the valve body <NUM> cannot be reduced, a cutout portion through which a protrusion portion of the female screw portion 31c of the valve body <NUM> can pass is formed in the large-diameter cylindrical portion 34A of the housing main body <NUM>.

In addition, the opening diameter of an opening 34b of the installation port portion <NUM> of the housing main body <NUM> has a larger diameter than the maximum dimension of the valve body <NUM>.

According to the foregoing configuration, as illustrated in <FIG>, while the valve body <NUM> which is fixed to the connection port portion 16A of the branch pipe <NUM> in a sealed manner is left, when the valve housing <NUM> which is another unnecessary valve component is pulled out and removed, the valve housing <NUM> can be easily pulled out along the branch axis direction without the installation port portion <NUM> of the housing main body <NUM> being caught by the valve body <NUM>. Therefore, it is possible to efficiently and easily perform a work of removing the valve housing <NUM> which is another valve component.

As illustrated in <FIG>, the large-diameter cylindrical portion 34A of the housing main body <NUM> is provided with a valve body-pressing portion <NUM> that presses the valve body <NUM> at the closed valve position against the ring-shaped valve seat surface <NUM> of the connection end surface 16a of the branch pipe <NUM> in a watertight state. The valve body-pressing portions <NUM> are provided in the large-diameter cylindrical portion 34A of the housing main body <NUM> at a plurality of locations (two locations in the circumferential direction in this embodiment) in the circumferential direction. Each of the valve body-pressing portions <NUM> includes a cam operation shaft <NUM> and an eccentric cam <NUM>. The eccentric cam <NUM> is supported by the large-diameter cylindrical portion 34A in a state where the eccentric cam <NUM> penetrates therethrough and is rotationally operable around a horizontal axis. The eccentric cam <NUM> is eccentrically provided in an inner end portion of the cam operation shaft <NUM>. As illustrated in <FIG> and <FIG>, due to the eccentric rotation of the eccentric cam <NUM>, the eccentric cam <NUM> is configured to be able to press the first packing <NUM>, which is installed on the flow path-blocking surface 31a of the valve body <NUM>, against the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM> from the branch axis direction in a watertight state.

As illustrated in <FIG>, the first packing <NUM> of the flow path-blocking surface 31a of the valve body <NUM> is most strongly pressed against the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM> by a cam surface portion in a cam surface 57a on the entire circumference of the eccentric cam <NUM>, the cam surface portion being on a semi-major axis side where the radius from an eccentric axis is maximum. The pressing force by the eccentric cam <NUM> gradually decreases as the eccentric cam <NUM> rotates to a cam surface portion side on a semi-minor axis side where the radius from the eccentric axis is minimum, and when the eccentric cam <NUM> rotates to the cam surface portion side on the semi-minor axis side or the vicinity thereof, the pressing force by the eccentric cam <NUM> is released.

Subsequently, a method of a renewal and earthquake resistance work including a valve removal method will be described.

[<NUM>] As illustrated in <FIG>, a split T-shaped pipe mounting step of externally mounting and fixing the split T-shaped pipe <NUM> having a split structure and including the branch pipe <NUM> on a portion upstream of a work target region of the fluid pipe <NUM> in a watertight state is executed.

Incidentally, for the description of the valve device <NUM>, <FIG> illustrates a state where the through-hole <NUM> is formed in the fluid pipe <NUM>; however, when the split T-shaped pipe <NUM> is installed, the through-hole <NUM> is not yet formed.

As illustrated in <FIG>, a valve device mounting step of mounting the valve device <NUM> to the branch pipe <NUM> of the split T-shaped pipe <NUM> in a watertight state is executed.

The valve device mounting step includes a housing-exterior mounting step of externally mounting the valve housing <NUM> of the valve device <NUM> on the first flange <NUM>, which is provided in the connection port portion 16A of the branch pipe <NUM>, from the branch axis direction, and a pulling and fixing step of pulling the valve housing <NUM> toward the first flange <NUM> of the branch pipe <NUM> by the pulling bolt <NUM> of the second fastening portion <NUM> provided in the valve housing <NUM>, and fixing the valve housing <NUM> to the first flange <NUM> in a watertight state in a sealed manner.

In the housing-exterior mounting step, the installation port portion <NUM> of the large-diameter cylindrical portion 34A forming the valve housing <NUM> of the valve device <NUM> is externally fitted and installed on the first flange <NUM> of the branch pipe <NUM> from the branch axis direction.

In the pulling and fixing step, the pulling bolts <NUM> are screwed into the screw holes <NUM> that are formed in a plurality of the reinforcement portions <NUM> in the installation port portion <NUM> of the large-diameter cylindrical portion 34A. As illustrated in <FIG>, the tapered surfaces 43a of the pulling bolts <NUM> come into contact with the pulling inclined surface 18a of the first flange <NUM> from outward in the radial direction, and as the pulling bolts <NUM> are tightened, the valve housing <NUM> of the valve device <NUM> is pulled toward and fixed to the connection port portion 16A side of the branch pipe <NUM>. Due to the pulling and fixing, the second packing <NUM> which is installed at the inner corner of the installation port portion <NUM> is compressed in a watertight state by the packing-pressing inclined surface 18b of the first flange <NUM>.

As illustrated in <FIG>, the waterstop bolt <NUM> including the waterstop washer <NUM> is screwed into each of the screw holes <NUM> from below, the screw holes <NUM> being formed in the first flange <NUM> of the branch pipe <NUM>, to prevent water from leaking from the screw hole <NUM> of the first flange <NUM>.

In addition, as illustrated in <FIG>, the hole closing tool <NUM> which has a split structure and closes all of the bolt insertion holes <NUM>, which are formed in the annular step portion 34D, in a watertight state is mounted on the outer peripheral surface of the small-diameter cylindrical portion 34B of the housing main body <NUM> and the upper surface of the annular step portion 34D. The two split closing members <NUM> of the hole closing tool <NUM> are fixed and coupled to each other in an annular shape by tightening the coupling flange portions 61A, which are provided in the end portions of the two split closing members <NUM> in the circumferential direction using the bolts <NUM> and nuts. Since the both split closing members <NUM> are fixed and coupled, the first elastic seal member <NUM> which seals the gap between the both split closing members <NUM> and the outer peripheral surface of the small-diameter cylindrical portion 34B of the housing main body <NUM> is compressed in a watertight state, and the second elastic seal member <NUM> which seals the gap between the both split closing members <NUM> and the upper surface of the annular step portion 34D is compressed in a watertight state.

Furthermore, as illustrated in <FIG> and <FIG>, the eccentric cam <NUM> of the valve body-pressing portion <NUM> provided in the large-diameter cylindrical portion 34A of the housing main body <NUM> is held in a pressing force release state where the eccentric cam <NUM> is spaced apart from the upper surface of the valve body <NUM>.

As illustrated in <FIG>, a drilling device mounting step (one example of a work equipment mounting step) of mounting the drilling device <NUM> which is one example of the work equipment <NUM> on the valve device <NUM> is executed.

In the drilling device mounting step, the third flange 82A of the short pipe <NUM> coupled to the drilling drive case <NUM> of the drilling device <NUM> is tightened and fixed to the second flange <NUM> of the housing main body <NUM> in a watertight state by bolts and nuts.

As illustrated in <FIG> and <FIG>, a drilling work performing step (one example of a work performing step) of performing a drilling work (one example of a predetermined work) where the rotary cutting tool <NUM> of the drilling device <NUM> is delivered inward toward a fluid pipe <NUM> side (refer to <FIG>) which is a work target portion upstream of the branch pipe <NUM> and the through-hole <NUM> is formed in the pipe wall of the fluid pipe <NUM> is executed.

In the drilling work performing step, the virtual line in <FIG> illustrates a state where the rotary cutting tool <NUM> of the drilling device <NUM> is delivered into the branch pipe <NUM> of the split T-shaped pipe <NUM>. <FIG> illustrates a state where after the drilling work is performed, the rotary cutting tool <NUM> holding the cut piece 1a of the pipe wall moves to return to an initial position above the valve body <NUM> inside the housing main body <NUM>.

A drilling device removing step (one example of a work equipment removing step) of removing the drilling device <NUM> from the valve device <NUM> after the valve body <NUM> of the valve device <NUM> is operated to the closed valve position is executed.

In the drilling device removing step, the fixing and coupling of the second flange <NUM> of the housing main body <NUM> to the third flange 82A of the short pipe <NUM> of the drilling device <NUM> is released, and the drilling device <NUM> is removed from the valve device <NUM>. In addition, when the valve body <NUM> of the valve device <NUM> is operated to the closed valve position, the cam operation shaft <NUM> of the valve body-pressing portion <NUM> provided in the large-diameter cylindrical portion 34A of the housing main body <NUM> is rotationally operated to a pressing operation position (refer to <FIG>). Due to the rotation of the cam operation shaft <NUM>, the cam surface portion on the semi-major axis side where the radius from the eccentric axis is maximum in the cam surface 57a on the entire circumference of the eccentric cam <NUM> presses the upper surface of the valve body <NUM>. Accordingly, the first packing <NUM> of the flow path-blocking surface 31a of the valve body <NUM> is maintained in a watertight state where the first packing <NUM> is crimped by the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM>.

In the flow path-closing device mounting step, the fourth flange 91A of the closing case <NUM> of the flow path-closing device <NUM> is tightened and fixed to the second flange <NUM> of the housing main body <NUM> in a watertight state by bolts and nuts. In this coupling state, the closing bag <NUM> in a reduced state, which is one example of the closing work portion and is accommodated in the closing case <NUM>, faces the internal flow path <NUM> of the housing main body <NUM>.

In the flow path closing work step, before the valve body <NUM> of the valve device <NUM> is operated to the open valve position, the cam operation shaft <NUM> of the valve body-pressing portion <NUM> is rotationally operated from the pressing operation position to a pressing release position, and the eccentric cam <NUM> is held in a pressing force release state where the eccentric cam <NUM> is spaced apart from the upper surface of the valve body <NUM>.

Subsequently, after the valve body <NUM> is operated to the open valve position, the operation cylinder shaft <NUM> is delivered inward from outside the closing case <NUM>, and the insertion guide cylinder body <NUM> and the closing bag <NUM> are integrally delivered inward. Thereafter, the insertion guide cylinder body <NUM> comes into contact with the opening peripheral edge of the through-hole <NUM> in the outer peripheral surface of the fluid pipe <NUM> to stop. In this state, when the operation cylinder shaft <NUM> is delivered further inward, the closing bag <NUM> is pulled out from the insertion guide cylinder body <NUM>, and the closing bag <NUM> is inserted into a predetermined close position in the in-pipe flow path from the through-hole <NUM> of the fluid pipe <NUM>. In this state, the fluid for diameter expansion is supplied into the closing bag <NUM> from the supply and discharge flow path 93a inside the operation cylinder shaft <NUM>, so that the closing bag <NUM> inflates to a state where the in-pipe flow path inside the fluid pipe <NUM> is closed.

In the flow path-closing device removing step, when the predetermined work is finished, the fluid for diameter expansion in the closing bag <NUM> which closes the in-pipe flow path inside the fluid pipe <NUM> is discharged from the supply and discharge flow path 93a inside the operation cylinder shaft <NUM>, so that the closing bag <NUM> is brought into a contracted state where the diameter thereof is reduced. In this state, the operation cylinder shaft <NUM> returns upward, so that the closing bag <NUM> and the insertion guide cylinder body <NUM> are accommodated in the closing case <NUM>.

Subsequently, after the valve body <NUM> is operated to the closed valve position, the coupling between the second flange <NUM> of the housing main body <NUM> and the fourth flange 91A of the closing case <NUM> is released, and the flow path-closing device <NUM> is removed from the valve device <NUM>. After the flow path-closing device removing step is finished, the procedure proceeds to the valve removal method.

As illustrated in <FIG>, a valve body fixing step of fixing the valve body <NUM> of the valve device <NUM> at the closed valve position to the connection port portion 16A of the branch pipe <NUM> in a sealed manner is executed.

The valve body fixing step includes valve body pressing step of pressing the valve body <NUM> at the closed valve position against the connection end surface 16a of the connection port portion 16A of the branch pipe <NUM> in a watertight state using the valve body-pressing portion <NUM> provided in the valve housing <NUM> of the valve device <NUM>, and a valve body fixing and coupling step of fixing and coupling the valve body <NUM>, which is pressed, to the first flange <NUM> of the branch pipe <NUM> in a watertight state using the valve-fixing bolt <NUM> and the nut <NUM> of the first fastening portion <NUM>.

In the valve body pressing step illustrated in <FIG>, the cam operation shaft <NUM> of the valve body-pressing portion <NUM> provided in the large-diameter cylindrical portion 34A of the housing main body <NUM> is rotationally operated to the pressing operation position, so that the upper surface of the valve body <NUM> is pressed by the cam surface portion on the semi-major axis side where the radius from the eccentric axis is maximum in the cam surface 57a on the entire circumference of the eccentric cam <NUM>. Accordingly, the first packing <NUM> of the flow path-blocking surface 31a of the valve body <NUM> is crimped in a watertight state by the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM>.

In the valve body fixing and coupling step illustrated in <FIG>, firstly, the waterstop bolts <NUM> with the waterstop washers <NUM> which are screwed into the screw holes <NUM> in the first flange <NUM> of the branch pipe <NUM> are detached. In addition, the two split closing members <NUM> of the hole closing tool <NUM> mounted on the outer peripheral surface of the small-diameter cylindrical portion 34B of the housing main body <NUM> and the upper surface of the annular step portion 34D are removed, so that all of the bolt insertion holes <NUM> formed in the annular step portion 34D are opened.

Subsequently, as illustrated in <FIG> and <FIG>, the valve-fixing bolts <NUM> are inserted into the housing main body <NUM> from the bolt insertion holes <NUM> of the annular step portion 34D, and the valve-fixing bolts <NUM> pass through the mounting holes <NUM> of the valve body <NUM> to be inserted into the screw holes <NUM> of the first flange <NUM>. The nuts <NUM> are screwed onto the tip side screw portions of the valve-fixing bolts <NUM> that protrude downward from the screw holes <NUM> of the first flange <NUM>, and the valve-fixing bolts <NUM> and the nuts <NUM> are tightened and fixed.

In a state where the valve body <NUM> is fixed to the first flange <NUM> of the branch pipe <NUM>, the first packing <NUM> of the flow path-blocking surface 31a of the valve body <NUM> is maintained in a watertight state where the first packing <NUM> is crimped by the ring-shaped valve seat surface <NUM> of the connection port portion 16A of the branch pipe <NUM>.

As illustrated in <FIG> and <FIG>, a valve component removing step of removing valve components of the valve device <NUM> other than the valve body <NUM> from the first flange <NUM> of the branch pipe <NUM> while the valve body <NUM> fixed to the first flange <NUM> of the branch pipe <NUM> is left is executed.

The valve component removing step includes a step of detaching and removing the operating member <NUM>, which has a substantially T shape and operates the valve body <NUM>, from the valve body <NUM> by an operation from outside the valve housing <NUM> of the valve device <NUM>.

In detail, as illustrated in <FIG>, firstly, the female screw portion 31c at the tip of the operating member <NUM>, which is screwed onto the male screw portion 53a of the valve body <NUM>, is detached therefrom, and then as illustrated in <FIG>, the valve housing <NUM> which is another valve component and is externally fitted and installed on the first flange <NUM> of the branch pipe <NUM> is lifted upward and removed.

In this case, the maximum dimension of the valve body <NUM> is the outer dimension in the diameter direction which passes through the center line of the female screw portion 31c; however, since the maximum dimension of the valve body <NUM> is a smaller diameter than the inner diameter D2 of the small-diameter inner peripheral surface 34a in the large-diameter cylindrical portion 34A of the housing main body <NUM>, or the cutout portion through which the protrusion portion of the female screw portion 31c of the valve body <NUM> can pass is formed in the large-diameter cylindrical portion 34A of the housing main body <NUM>, the valve housing <NUM> can be smoothly pulled out along the branch axis direction without the large-diameter cylindrical portion 34A of the housing main body <NUM> being caught by the valve body <NUM>.

<FIG> and <FIG> illustrate a first example of the opening and closing operation structure of the valve device <NUM> in the second embodiment. In the valve device <NUM> of the first example, a screw piece <NUM> is screwed onto a screw portion 20a of a valve shaft <NUM> that is supported on the valve housing <NUM> and is rotationally operable from outside. A coupling portion <NUM> which detachably couples the screw piece <NUM> and the valve body <NUM> is provided such that the coupling portion <NUM> can be decoupled from outside the valve housing <NUM>.

The coupling portion <NUM> is formed by screwing a coupling bolt 22A, which is inserted into a through-hole 21a penetrating through the screw piece <NUM>, into the female screw portion 31c of the valve body <NUM>.

For this reason, as illustrated in <FIG>, it is possible to easily perform the screw coupling operation of the coupling bolt 22A with respect to the female screw portion 31c of the valve body <NUM> and perform a screw release operation from outside the housing main body <NUM> by detaching the valve guide case <NUM> from the valve guide cylinder portion 34C of the housing main body <NUM>.

Incidentally, since other configurations are the same as the configurations described in the second embodiment, the same reference numbers as those in the first embodiment are assigned to the same components, and the descriptions thereof will be omitted.

<FIG> illustrates a second example of a structure where the first flange <NUM> of the branch pipe <NUM> and the valve body <NUM> are fixed and coupled to each other in the second embodiment. In the valve device <NUM> of the second example, through-holes <NUM> serving as coupling holes into which valve-fixing bolts <NUM> that fix the valve body <NUM> at the closed valve position in a watertight state are inserted from below are formed in the first flange <NUM> of the branch pipe <NUM> at a plurality of locations (six locations in this embodiment) in the circumferential direction. In addition, screw holes <NUM> which are screwed onto the valve-fixing bolts <NUM> inserted into the through-holes <NUM> of the first flange <NUM> are formed in the valve body <NUM> at a plurality of locations (six locations in this embodiment) in the circumferential direction.

In the second example, it is not required that as in the second embodiment, the bolt insertion hole <NUM> through which the valve-fixing bolt <NUM> is inserted into the internal space of the housing main body <NUM> is formed in the annular step portion 34D of the housing main body <NUM>, and it is not also required that as in the second embodiment, when the valve body <NUM> is not fixed to the first flange <NUM>, the hole closing tool <NUM> which has a split structure and closes all of the bolt insertion holes <NUM> in a watertight state is mounted on the housing main body <NUM>. For this reason, it is possible to simplify the valve device <NUM> and improve the work efficiency.

Claim 1:
A valve removal method of a fluid pipeline structure, which removes an unnecessary portion of a valve device (<NUM>) from a connection port portion (16A) side of a pipe (<NUM>) without flow disruption in the fluid pipeline structure where the valve device (<NUM>), which includes a valve body (<NUM>) that is openable and closeable from a direction intersecting a flow path axis of a connection port portion (16A) and a valve housing (<NUM>) accommodating the valve body (<NUM>), is detachably provided on the connection port portion (16A) side of the pipe (<NUM>) connected to a fluid piping system, the method comprising:
a valve body (<NUM>) fixing step of fixing the valve body (<NUM>) at a closed valve position to the connection port portion (16A) side in a sealed manner; and
a valve component removing step of removing other unnecessary valve components including the valve housing (<NUM>) in the valve device (<NUM>) in a state where the valve body (<NUM>) which is fixed in a sealed manner is left on the connection port portion (16A) side.