Sluice valve for operations

An operation for securing and coupling a coupling flange and a fluid device mounted through the interior of a valve case of a sluice valve for operations can be performed with good efficiency from the exterior while sufficiently ensuring the external mounting depth of the coupling tube part on the coupling flange and while facilitating the attachment of pulling and securing means and ensuring the attachment strength. A valve element (31) that is freely movable in a direction orthogonal to a pipe axial center and valve operation means (30) for movably operating the valve element (31) are provided to a valve case (32), which is provided with a coupling tube part (32C) that can be externally mounted on a coupling flange of a connecting pipe from the pipe axial center direction; pulling and securing means for pulling and securing the valve case (32) to the coupling flange is disposed on the coupling tube part (32C) of the valve case (32); and an operation recess (32J) for operating a fastener from a rear surface side of the coupling flange is formed in the coupling tube part (32C) of the valve case (32), the fastener being used for securing and coupling the coupling flange and the fluid device that is joined to the coupling flange through a flow channel inside the valve case (32).

TECHNICAL FIELD

The present invention relates to a sluice valve for operations mainly used in the case that, e.g., a cover body for sealing off an end part opening of a connecting pipe, or a valve case of a sluice valve or other fluid device is attached to a coupling flange formed on an end part of a branching pipe or another connecting pipe while the flow of a fluid in the pipe is maintained.

BACKGROUND ART

In a conventional sluice valve for operations, a valve element capable of moving in the orthogonal direction in relation to the pipe axial center of the connection pipe, and valve operation means for movably operating the valve element between open and closed valve positions are provided to a valve case, which is provided with a coupling tube part capable of being externally mounted on a coupling flange of the connecting pipe from the pipe axial center direction; and pulling and securing means for pulling and securing the valve case to the coupling flange is disposed on the coupling tube part of the valve case.

The pulling and securing means comprises threading bolts in a plurality of locations in the circumferential direction of the coupling tube part of the valve case, the bolts being provided with a conical pressing surface that can engage with the external peripheral edge of the back surface side of the coupling flange from the outer side in the radial direction of the pipe.

The coupling part of the fluid device mounted through the flow channel inside the valve case of the sluice valve for operations is joined with the coupling flange of the connecting pipe, and the coupling part of the fluid device and the coupling flange of the connecting pipe are secured and coupled when the plurality of bolts, which is an example of a fastener, are threadably operated through the opening of the coupling tube part of the valve case.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

In a conventional sluice valve for operations, a coupling tube part of the valve case is externally mounted on the coupling flange of the connecting pipe from the pipe axial center direction, thereby ensuring a large flow channel inside the valve case that allows passage of a fluid device having a size that corresponds to the coupling flange of the connecting pipe.

It is possible to simplify the structure of the pulling and securing means because the coupling tube part of the valve case can be dually configured as a pulling force-transmitting medium when the valve case is pulled and secured to the coupling flange of the connecting pipe.

On the other hand, the opening end edge of the coupling tube part projects more considerably in the pipe axial center direction than the back surface of the coupling flange of the connecting pipe due to a relationship in which the conical pressing surface of the bolt threaded in an intermediate position in the pipe axial center direction of the coupling tube part of the valve case is made to engage the external peripheral edge of the back surface side of the coupling flange.

For this reason, when the coupling flange of the connecting pipe and the coupling part of the fluid device mounted through the flow channel inside the valve case of the sluice valve for operations are secured and coupled by a plurality of bolts mounted and operated from the opening side of the coupling tube part of the valve case, the bolts must be fastenably operated while the opening of the coupling tube part of the valve case that projects considerably more in the pipe axial center direction than the back surface of the coupling flange is viewed from the pipe axial center direction; and since there are also spatial restrictions, time tends to be required to perform the securing and coupling operation.

In the particular case that the connecting pipe is composed of a branching pipe of the pipe joint which pipe joint is provided with a plurality of divided joint bodies detachably secured and coupled along the circumferential direction of a fluid pipe, and the branching pipe that communicates with a through-hole in the fluid pipe is projectingly disposed on one of the divided joint bodies, the opening end edge of the coupling tube part is in close contact with the external peripheral surface of the divided joint bodies. In order to ensure operation space between the opposing surfaces of the opening end edge of the coupling tube part and the external peripheral surface of the projectingly disposed divided joint bodies, the projecting length of the branching pipe must be increased, which disadvantageously leads to an increase in the size of the pipe joint and other components.

The present invention was devised in view of the foregoing, and a main object of the present invention is to provide a sluice valve for operations that sufficiently ensures the external mounting depth of the coupling tube part in relation to the coupling flange of the connecting pipe, so as to enable efficient and simple securing and coupling operation between the coupling flange of the connecting pipe and the coupling part of the fluid device mounted through the flow channel inside the valve case of the sluice valve for operations while the attachment of the pulling and securing means is facilitated and the attachment strength is ensured.

Solution to Problem

A first aspect of the present invention is a sluice valve for operations in which a valve element that is freely movable in a direction orthogonal to a pipe axial center and valve operation means for movably operating the valve element between a closed valve position and an open valve position are provided to a valve case, which is provided with a coupling tube part that can be externally mounted on a coupling flange of a connecting pipe from the pipe axial center direction; and pulling and securing means for pulling and securing the valve case to the coupling flange is disposed on the coupling tube part of the valve case in a state engaged with the rear surface of the coupling flange, the sluice valve for operations having an operation recess formed on the coupling tube part of the valve case, and adapted for operating a fastener from a rear surface side of the coupling flange, the fastener being used for securing and coupling the coupling flange and a fluid device, which fluid device is joined to the coupling flange through a flow channel inside the valve case.

According to this aspect, when the coupling flange of the connecting pipe and the fluid device joined through a flow channel in the valve case are secured and coupled by a fastener that is mounted and operated from the opening side of the coupling tube part of the valve case in a state in which the coupling tube part of the valve case is externally mounted from the axial center direction on the coupling flange of the connecting pipe, and the valve case is pulled and secured to the coupling flange of the connecting pipe by pulling and securing means disposed in the coupling tube part, the fastener can be readily fastened and operated in an simple orientation from the external side in the radial direction of the coupling tube part of the valve case through an operation recess formed in the coupling tube part, even in a state in which the opening end edge of the coupling tube part of the valve case projects more considerably in the pipe axial center direction than the rear surface of the coupling flange.

Therefore, it is possible to readily perform operations for securing and coupling the coupling flange of the connecting pipe and the fluid device joined thereto through the flow channel inside the valve case with good efficiency in a simple orientation while a configuration is used in which the coupling tube part of the valve case is externally fitted and mounted on the coupling flange of the connecting pipe, the flow channel inside the valve case is enlarged, the structure of the pulling and securing means is simplified, and a strong pulling and securing function in a medium for transmitting the force for pulling a robust coupling tube part is ensured, regardless of the presence of a coupling tube part of the valve case that projects considerably further in accompaniment therewith in the pipe axial center direction than the rear surface of the coupling flange of the connecting pipe.

In a second aspect of the present invention, the connecting pipe is composed of a branching pipe of a pipe joint, the pipe joint being provided with a plurality of divided joint bodies detachably secured and coupled along the circumferential direction of a fluid pipe, and the branching pipe, which communicates with a through-hole in the fluid pipe, being projectingly provided to one of the divided joint bodies.

According to this aspect, when the coupling flange of the branching pipe of the pipe joint externally mounted on the fluid pipe and the fluid device joined through the flow channel inside the valve case are to be secured and coupled by a fastener that is mounted and operated from the opening side of the coupling tube part of the valve case, it is possible to readily fasten and operate the fastener in a simple orientation from the outer side in the radial direction of the coupling tube part through the operation recess formed in the coupling tube part, even when the opening end edge of the coupling tube part of the valve case projects considerably further in the pipe axial center direction than the rear surface of the coupling flange and closely approaches the external peripheral surface of the divided joint body to which the branching pipe is projectingly provided.

Therefore, a large operations space is not required to be ensured between the external peripheral surface of the divided joint bodies and the opening end edge of the coupling tube part of the valve case opposing to the external peripheral surface, and as a result, the projecting length of the branching pipe can be shortened by an equivalent amount and the pipe joint and other components can be reduced in size.

In a third aspect of the present invention, a seal material is detachably mounted on a downstream-side surface among two surfaces of the valve element in the pipe axial center direction, the seal material sealing off a space formed with respect to a valve seat inside the valve case that faces, in the pipe axial center direction, one surface of the valve element in a closed valve position; and the valve case is composed of at least a plurality of divided valve case bodies separably divided in a position in which is formed an opening via which the valve element can be removed to the exterior.

According to this aspect, when the valve element is in the closed valve position, the seal material disposed on one surface on the downstream side of the valve element is pressed into contact with the valve seat inside the valve case in a mode that makes use of water pressure, and the space between the valve element and the valve seat inside the valve case can be sealed with good efficiency. Also, it is possible to readily replace the seal material with good efficiency in an external wide space in the case that the seal material of the valve element is periodically replaced, because the plurality of divided valve case bodies constituting the valve case can be disassembled and the valve element can be removed from the opening in the divided valve case bodies.

In a fourth aspect of the present invention, there is disposed in the valve case pressing means for imparting downstream-oriented pressing and moving force to another upstream side surface of the valve element in the closed valve position to bring the valve element into contact under pressure with the valve seat in the valve case.

According to this aspect, it is possible to reliably provide a seal with good efficiency between the valve element and the valve seat inside the valve case with the aid of the fluid pressure and the downstream pressing and moving force produced by the pressing means.

In a fifth aspect of the present invention, the pulling and securing means is composed of a bolt threaded from the exterior in the radial direction of the pipe in a plurality of locations in the circumferential direction of the coupling tube part; and the operation recess is formed in a medial location between adjacent bolts of the coupling tube part.

According to this aspect, when the coupling flange of the connecting pipe and the fluid device joined thereto through a flow channel inside the valve case are secured and coupled by a fastener mounted and operated from the opening side of the coupling tube part of the valve case, the fastener can be readily fastenably operated in a simple orientation from the external side in the radial direction of the coupling tube part through the operation recess formed in the coupling tube part, even when the opening end edge of the coupling tube part of the valve case projects considerably further in the pipe axial center direction than the rear surface of the coupling flange.

Additionally, the attachment strength of the bolt can be ensured because the operation recess is formed between adjacent bolts of the plurality of bolts constituting the pulling and securing means.

In a sixth aspect of the present invention, the thickness of a first peripheral wall portion of the coupling tube part of the valve case is configured to be greater than the thickness of a second peripheral wall portion, the first peripheral wall portion being formed in the shape of a strip or substantially in the shape of a strip along the pipe axial center direction in a state that includes a location in which the pulling and securing means is attached, and the second peripheral wall portion being formed in the shape of a strip or substantially the shape of a strip along the pipe axial center direction in a state that includes a location in which the operation recess is formed; and an inside surface of the first peripheral wall portion of the coupling tube part and an inside surface of the second peripheral wall portion are formed as an inside peripheral surface having the same inside diameter.

According to this aspect, the thickness of a first peripheral wall portion of the coupling tube part, the first peripheral wall portion being formed in the shape of a strip or substantially in the shape of a strip along the pipe axial center direction in a state that includes the location in which the pulling and securing means is attached, is configured to be greater than the thickness of a second peripheral wall portion, which is formed in the shape of a strip or substantially in the shape of a strip along the pipe axial center direction in a state that includes the location in which the operation recess is formed; and the location in which the valve case is pulled and secured to the coupling flange of the connecting pipe is robustly configured. Nevertheless, the operation for fastening the fastener by way of the operation recess can be readily carried out without interference from the thick first peripheral wall portion because the outside surface of the second peripheral wall portion is positioned further inward in the radial direction of the pipe than the outside surface of the first peripheral wall portion.

In a seventh aspect of the present invention, the first peripheral wall portion is formed in a plurality of locations in the circumferential direction of the coupling tube part of the valve case, the second peripheral wall portion is arranged between adjacent first peripheral wall portions, and the length of the second peripheral wall portion in the circumferential direction is configured to be greater than the length of the operation recess in the circumferential direction.

According to this aspect, the operation for fastening the fastener by way of the operation recess can be more readily carried out without interference from the thick first peripheral wall portion.

DESCRIPTION OF EMBODIMENTS

First Embodiment

FIGS. 1 to 29show a renovation method for replacing a to-be-renovated pipeline assembly A as an example of a to-be-renovated pipeline assembly that is embedded in the earth and that constitutes a part of a circulatory piping system in the piping system of a water supply pipe, which is an example of a fluid pipe, with a new pipe assembly B such as that shown inFIGS. 23 to 26in a state of nonstop water supply in which the flow of a water supply (clean water) is maintained, where the to-be-renovated pipeline assembly A comprises a cast-iron short pipe2fittably connected in a watertight state to an end part of one cast-iron water supply pipe1, a sluice valve3that is flange-joined in a water-tight state to the other end part of the short pipe2, a cast-iron connecting pipe4that is flange-joined in a watertight state to another end part of the sluice valve3, and a collar5that connects in a watertight state the other end part of the connecting pipe4and the end part of the other cast-iron water supply pipe1. Following is a description of operations steps, including a structural description of the sluice valve for operations D used in the renovation method.

(1) The operations step ofFIG. 1shows a step for excavating a slightly larger range than a renovation operations area W of the water supply pipe1embedded in the earth, and forming a work pit (operations pit) P exposed by the renovation operations area W of the water supply pipe1; and a step for laying out crushed stone11on the bottom surface of the work pit P and a building a stable horizontal operations bottom surface without depressions.

The cross-sectional structure of the to-be-renovated pipeline assembly A is not disclosed inFIG. 1, but the type of sluice valve3is the largest point of difference in comparison with the new pipeline assembly B, and the joint structures of the components are otherwise substantially the same.

An example of the joining structure of the to-be-renovated pipeline assembly A will be described with reference to the cross-sectional structure of the new pipeline assembly B shown inFIGS. 23 to 26. A packing6is interposed between a tapered internal peripheral surface2aon the receiving mouth side of the short pipe2and the external peripheral surface of one of the water supply pipes1, and a pressing ring7externally mounted on the water supply pipe1and a coupling flange2A of one end of the short pipe2are fastenably secured by a bolt8and a nut9, or other fastening means, whereby the packing6is compressed to a watertight state by the pressing ring7.

A coupling flange2B of the other end of the short pipe2and a coupling flange3A of one end of the sluice valve3, and a coupling flange3B on the other end of the sluice valve3and a coupling flange4A of one end of the connecting pipe4are secured and coupled in a watertight state by a bolt8and nut9, or other fastening means in a state in which a sheet packing or other seal material is interposed between the flange-joined surfaces.

The packing6is interposed between a tapered internal peripheral surface5aof one end of the collar5and the external peripheral surface of the connecting pipe4, and between a tapered internal peripheral surface5bof the other end of the collar5and the external peripheral surface of the other water supply pipe1. The pressing ring7externally mounted on the connecting pipe4and a coupling flange5A of one end of the collar5, and the pressing ring7externally mounted on the other water supply pipe1and a coupling flange5B of the other end of the collar5are each fastenably secured by the bolt8and nut9, or other fastening means. The packing6is thereby compressed by the pressing ring7until a watertight state is achieved.

A renovation method for replacing the to-be-renovated pipeline assembly A with a new pipeline assembly B provided with substantially the same function is described in this embodiment, but the form and function of the to-be-renovated pipeline assembly A may be completely different from the form and function of the new pipeline assembly B.

In this embodiment, a part of one of the water supply pipes1and a part of the other water supply pipe1are cut by a pipe cutting apparatus (not shown), and the to-be-renovated pipeline assembly A is separated and removed from the water supply pipe1, as shown inFIG. 22. Therefore, the entire length L of the to-be-renovated pipeline assembly A is a dimension that includes the cut pipe parts of the two water supply pipes1.

(2) The operations steps ofFIGS. 2 and 3shows a step for delivering and arranging a metal installation base15that is provided with stable grounding properties and rigidity (mechanical strength) that can stop relative approaching movement in the pipe axial center direction of the two remaining pipe parts1A,1B of the water supply pipe1during separation and removal (seeFIG. 22) of the to-be-renovated pipeline assembly A in the operations bottom surface of the work pit P, which is the ground of the to-be-renovated operations location that corresponds to the renovation operations area W of the water supply pipe1; a step for externally mounting and securing the split T-shaped pipe17in two locations at the two ends of the renovation operations area W of the water supply pipe1, the split T-shaped pipe17being bisected at a position along the horizontal surface that passes through or near the pipe axial center of the water supply pipe1in an example of a pipe joint provided with a branching pipe17C in a location that corresponds to a through-hole (example of an opening)16formed in the pipe wall of the water supply pipe1; and a step for securing and coupling to the installation base15pipe holders18for holding and securing the two locations at the two ends of the renovation operations area W of the water supply pipe1, and a pipe supporter19for supporting the center position in the pipe axial center direction of the to-be-renovated pipeline assembly A in the renovation operations area W of the water supply pipe1.

The installation base15delivery and arrangement step, the split T-shaped pipe17external mounting and securing step, the pipe holder18attaching step, and the pipe supporter19attaching step can be carried out simultaneously, but it is preferred that the installation base15be delivered and arranged, the locations that correspond to the renovation operations area W of the water supply pipe1be firmly secured and supported by the pipe holders18and pipe supporter19attached to the installation base15, and the split T-shaped pipe17thereafter be externally mounted and secured to the water supply pipe1.

As shown inFIGS. 3 to 5, the split T-shaped pipe17is composed of semi-cylindrical divided joint bodies17A,17B that have been bisected in the pipe circumferential direction so as to be capable of being externally mounted on the water supply pipe1from two side directions in the radial direction of the pipe. The split T-shaped pipe17has coupling flanges17a,17bfor detachably securing and coupling the two divided joint bodies17A,17B, which are externally mounted on the water supply pipe1, via a plurality of bolts8and nuts9as an example of the fastening means, the coupling flanges17a,17bbeing integrally formed at the two end parts of the divided joint bodies17A,17B in the pipe circumferential direction; and a branching pipe (an example of a connecting pipe)17C for providing communication in the radial direction of the pipe with the through-hole16formed in the pipe wall of the water supply pipe1, the branching pipe17C being projectingly formed in an integral fashion in the center part in the pipe circumferential direction and in the center part in the pipe axial center direction of the upper divided joint body17A, which is externally mounted on the upper half of the water supply pipe1.

Securing bolts20that are threadably operated in a state biting into the external peripheral surface of the water supply pipe1from the exterior in the radial direction of the pipe are provided in a plurality of locations in the circumferential direction of the two ends of the two divided joint bodies17A,17B in the pipe axial center direction, and this plurality of securing bolts20are fastenably operated, whereby the split T-shaped pipe17is firmly secured in a predetermined orientation to the water supply pipe1and a rubber packing21for maintaining a watertight state between the external peripheral surface of the water supply pipe1is mounted in a seal-holding groove formed in the internal peripheral surface of the two divided joint bodies17A,17B.

When attachment of the split T-shaped pipe17has been completed, a flange cover (not shown) for sealing the upper opening of the branching pipe17C in a watertight state is attached to a coupling flange17D on the upper end of the branching pipe17C, and water is injected into the internal space between the internal peripheral surface of the split T-shaped pipe17and the external peripheral surface of the water supply pipe1at a pressure that corresponds to water supply pressure to perform a water pressure test and check for the presence of a leak.

When this water pressure test is passed, a super-hardening cement (jet cement)23, which is an example of a reinforcement filling material, is filled into the internal space between the internal peripheral surface of the split T-shaped pipe17and the external peripheral surface of the water supply pipe1in a state excluding the formation area of the through-hole16, and the pipe wall of the water supply pipe1in which the through-hole16is formed is reinforced, as shown inFIG. 3.

As shown inFIGS. 2 and 4, the installation base15can be stably grounded on the operations bottom surface of the work pit P, and is formed of a steel material provided with rigidity that can stop relative approaching movement in the pipe axial center direction of the two remaining pipe sections1A,1B of the water supply pipe1during separation and removal of the to-be-renovated pipeline assembly A. One example of the installation base15is composed of two H-shaped steel sections (e.g., 200 (H dimension)×200 (B dimension)) that can be juxtaposed along the pipe axial center direction on the lower side of the location corresponding to the renovation operations area W of the water supply pipe1.

The two H-shaped steel sections are configured with a length that is greater than the entire length L of the to-be-renovated pipeline assembly A by an amount equal to the space for attaching the two pipe holders18; a lower-side web15A of the two H-shaped steel sections is configured as the grounded plate part and an upper-side web15B is configured as the attachment plate part for the pipe holders18and the pipe supporter19.

The pipe holders18are composed of a pipe-bearing member18A provided with a semi-arcuate pipe-bearing part18afor bearing and supporting the lower half part of the external peripheral surface of the water supply pipe1; a pipe-pressing member18B provided with a semi-arcuate pipe-pressing part18bcapable of pressing and securing the upper half part of the external peripheral surface of the water supply pipe1; and an attachment base18C for securing and coupling the pipe-bearing member18A to the upper-side web15B of the two H-shaped steel sections, as shown inFIG. 3.

Coupling flanges18d,18efor detachably holding and securing the pipe-bearing part18aand the pipe-pressing part18bto the external peripheral surface of the water supply pipe1via a plurality of bolts8and nuts9as an example of the fastening means are integrally formed on the two ends of the pipe-bearing part18aof the pipe-bearing member18A in the pipe circumferential direction and on the two ends of the pipe-pressing part18bof the pipe-pressing member18B in the pipe circumferential direction. Securing bolts22that are threadably operated in a state biting into the external peripheral surface of the water supply pipe1from the exterior in the radial direction of the pipe are provided in a plurality of locations in the pipe circumferential direction of the pipe-bearing part18aand in a plurality of locations in the pipe circumferential direction of the pipe-pressing member18B, and the plurality of securing bolts22is fastenably operated, whereby the pipe holder18is firmly secured to the water supply pipe1in a predetermined orientation.

A coupling flange18gis formed on the upper end of the attachment base18C, and is secured and coupled to a coupling flange18fon the lower end of the pipe-bearing member18A via a plurality of bolts8and nuts9as an example of the fastening means. A coupling flange18his formed on the lower end of the attachment base18C, and is secured and coupled to the upper-side web15B of the two H-shaped steel sections15via a plurality of bolts8and nuts9as an example of the fastening means.

The lower side coupling flange18hof the attachment base18C is attached across the upper-side web15B of the two H-shape steel sections, and therefore doubles as a coupling member for securing and coupling the two H-shaped steel sections together.

The pipe holder18is firmly secured to the water supply pipe1in a state in which the coupling flange18dof the pipe-bearing member18A and the coupling flange18eof the pipe-pressing member18B are in contact with (or adjacent to) one end of the two divided joint bodies17A,17B of the split T-shaped pipe17in the pipe axial center direction, as shown inFIG. 3.

For this reason, the two split T-shaped pipes17firmly secured to the water supply pipe1are dually configured as a pipe-securing members that are secured in the two locations at the two ends of the renovation operations area of the water supply pipe1; and the two pipe holders18firmly secured to the water supply pipe1are in contact from the pipe axial center direction with the two split T-shaped pipe17dually configured as a pipe-securing member, and are dually configured as movement stoppers that can stop relative approaching movement of the two remaining pipe parts1A,1B of the water supply pipe1in the pipe axial center direction when the to-be-renovated pipeline assembly A is separated and removed.

The pipe supporter19is composed of a pipe-bearing member19A provided with a semi-arcuate pipe-bearing part19afor bearing and supporting the lower half part of the external peripheral surface of the connecting pipe4, which is a constituent member of the to-be-renovated pipeline assembly A; a substantially U-shaped tap bolt19B that is mounted from above on the upper half part of the external peripheral surface of the connecting pipe4; and an attachment base19C for securing and coupling the pipe-bearing member19A to the upper-side web15B of the two H-shaped steel sections, as shown inFIG. 2.

A fastening nut24and a lock nut25are threaded onto the two screw shaft parts of the tap bolt19B inserted through the through-holes at the two ends of the pipe-bearing part19ain the circumferential direction, and the fastening nut24and lock nut25are fastenably operated, whereby the pipe-bearing member19A and tap bolt19B of the pipe supporter19are held and secured to the connecting pipe4.

A coupling flange19eis formed on the upper end of the attachment base19C, and is secured and coupled to a coupling flange19don the lower end of the pipe-bearing member19A via a plurality of bolts8and nuts9as an example of the fastening means. A coupling flange19fis formed on the lower end of the attachment base19C, and is secured and coupled to the upper-side web15B of the two H-shaped steel sections via a plurality of bolts8and nuts9as an example of the fastening means.

A pipe-securing and pipe-supporting apparatus C used in the renovation method is composed of two H-shaped steel sections that constitute the installation base15, and the two pipe holders18and the pipe supporter19.

The installation base15is delivered and arranged on the ground in the renovation operations location that corresponds to the renovation operations area W of the water supply pipe1, and is used for merely securing the two pipe holders18. Therefore, there is no need for a curing period such as for the case in which a concrete base and concrete struts are built, and the installation base15can be removed and delivered unaltered to the next construction site after the new pipeline assembly B has been connected to the two remaining pipe parts1A,1B of the removed water supply pipe1.

(3) The operations steps ofFIGS. 4 and 5show the steps for securing and coupling a valve case32of the sluice valve for operations D to the coupling flange17D on the branching pipe17C of the split T-shaped pipe17in a watertight state, the sluice valve for operations D being provided with a valve element31, which is actuated so as to open and close in the horizontal direction by the rotating operation of valve operation means30. The details of the sluice valve for operations D are shown inFIGS. 6 to 16.

As shown inFIGS. 13 to 15, a cylindrical lower coupling tube part32C that can be externally fitted and mounted from above on the coupling flange17D of the branching pipe17C is integrally formed on the lower part of the valve case32of the sluice valve for operations D; and an annular working part32D that is in contact in a riding state with a peripheral edge part of the upper surface of the coupling flange17D of the branching pipe17C is integrally formed on the upper part of the internal peripheral surface of the lower coupling tube part32C and in a proximal location below the opening and closing movement pathway of the valve element31. The lower coupling tube part32C is provided with pulling and securing means33which is configured, when the annular working part32D is resting on and supported by the coupling flange17D of the branching pipe17C, to pull and secure the valve case32to the coupling flange17D while the pulling and securing means33is coupled to the lower surface (rear surface) of the coupling flange17D.

As shown inFIGS. 12 to 15, a cylindrical upper coupling tube part32E that forms a flow channel inside the valve concentrically through the lower coupling tube part32C is integrally formed in the upper part of the valve case32; and a coupling flange32F for attaching a drill27, a flow channel cut-off apparatus40, or the like is integrally formed on the opening end of the upper coupling tube part32E. A guiderail32G for bearing in a riding state the lower surface of sliding parts31A (which is the upstream side surface on the water supply pipe1side) projectingly formed on the left and right sides of the valve element31to slidably guide the two sliding parts31A of the valve element31between a closed valve position and an open valve position is formed on the left and right inside walls that face the opening and closing movement pathway inside the valve case32.

As shown inFIGS. 13 to 15, an annular valve seat32I, with which an annular sealing and pressing surface31aof the valve element31is in contact from the pipe axial center direction, is formed on the inside wall that faces the opening and closing movement pathway inside the valve case32in a location that faces the annular sealing and pressing surface31aon the upper surface of the valve element31(side surface on the downstream side) in an open valve position. An O-ring34, which is an example of the seal material that provides a watertight state with the valve seat32I of the valve case32, is detachably mounted in a seal holding groove31bformed in the annular sealing and pressing surface31aof the valve element31. Pressing means35for imparting downstream pressing and moving force to the lower surface (the side surface of the upstream side) of the valve element31in the closed valve position to press the O-ring34mounted in the seal holding groove31bof the valve element31against the valve seat32I inside of the valve case32is disposed in the valve case32.

The pressing means35is configured as shown inFIGS. 12 and 16, wherein a bushing35D for rotatably supporting an operation shaft35A about the horizontal axial center offset slightly below the lower surface of the valve element31, which is in a state of contact with the upper surface of the guiderail32G, is secured by a locking screw35E to a first bearing part32K formed in the side wall facing the opening and closing movement pathway of the valve element31inside the valve case32on the left and right sides facing the two sliding parts31A of the valve element31in a closed valve position; an eccentric cam35B that is capable of changing between a non-pressing state and a pressing state is fixed to the operation shaft35A that passes through and is supported by the bushing35D and that projects inside the valve case32, the non-pressing state being a state in which the eccentric cam35B is set at a distance below the lower surface of the two sliding parts31A of the valve element31in accompaniment with the rotation of the operation shaft35A, and the pressing state being a state in which the eccentric cam35B presses the lower surface of the two sliding parts31A upward (downstream side) to the closed valve position in which the O-ring34mounted in the seal holding groove31bof the valve element31is pressed against the valve seat32I of the valve case32; and an operation handle35C is fixed to the shaft part projecting outside the valve case32the operation shaft35A.

The valve case32is composed of divided valve case bodies32A,32B that are separably bisected in a position where the opening is formed that allows the valve element31to be removed to the exterior, i.e., in a position that traverses in the crosswise direction the two sliding parts31A of the valve element31in the open valve position, as shown inFIGS. 6 to 15. The two coupling tube parts32C,32E and the guiderail32G are provided to the first divided valve case body32A, and the second divided valve case body32B has a second bearing part32H that passes through and rotatably supports one end of a valve stem30A of the valve operation means30.

A coupling flange32aformed in the opening of the separation side of the first divided valve case body32A and a coupling flange32bformed in the opening of the separation side of the second divided valve case body32B are detachably secured and coupled in a watertight state via bolts8or other fastening means. Slightly less than half of the valve element31in the open valve position is configured so as to be exposed to the exterior by way of the opening of the separation side of the first divided valve case body32A in a state in which the second divided valve case body32B has been removed, and the valve element31is configured so as to be capable of being removed to the exterior from the opening of the separation side of the first divided valve case body32A.

The valve operation means30is provided with, as a main configuration, the valve stem30A on which an externally-threaded screw is formed on the external peripheral surface, a screw piece30B threaded from the other end of the valve stem30A, and an operation handle30C mounted in an integral rotating state on the shaft end30aof the valve stem30A that projects from the second divided valve case body32B, as shown inFIGS. 12 to 15.

The screw piece30B is accommodated in a state that allows upward movement (downstream side) inside an accommodation concavity31B of the upper opening formed in the base part of the valve element31that corresponds to the bearing part32H of the second divided valve case body32B, and is accommodated in a state that stops co-rotation when the valve stem30A is rotatably operated. A stopper member30D is attached to the bearing part32H of the second divided valve case body32B, the stopper member30D being used for stopping yet rotatably supporting the shaft portion contiguous to the shaft end30afor mounting the handle of the valve stem30A.

As shown inFIGS. 14 and 15, a bolt33A is provided with a tapered pressing surface33athat makes contact from the horizontal direction with a tapered surface17dformed on the external peripheral edge part of the lower surface of the coupling flange17D, and the pulling and securing means33threads the bolt33A into a screw hole33B formed in an area where the rotatably operated shaft is positioned on the horizontal plane that passes through the lower surface (rear surface) of the coupling flange17D in a plurality of locations (six locations in this embodiment) in the circumferential direction of the lower coupling tube part32C of the valve case32and in a state in which the annular working part32D rides on and is supported by the coupling flange17D. An O-ring36, which is an example of the seal material, is mounted on the inside corner location formed by the internal peripheral surface of the lower coupling tube part32C and the lower surface of the annular working part32D, and the annular working part32D of the valve case32is firmly held and secured while being pulled to the upper surface side of the coupling flange17D of the branching pipe17C in accompaniment with the fastening operation of the bolt33A, and while the O-ring36is compressed to a watertight state.

An operation recess32J in a shape of a cutout is formed between adjacent screw holes33B of the pulling and securing means33in the lower coupling tube part32C of the valve case32, the operation recess32J being used for operating a securing bolt54from the lower surface (rear surface) of the coupling flange17D, the securing bolt54being an example of the fastener for securing and coupling the coupling flange17D of the branching pipe17C and the fluid device E (e.g., a cover body55capable of sealing the opening of the branching pipe17C of the split T-shaped pipe17in a watertight state, as shown inFIGS. 27 and 28; or a valve case72of the sluice valve F, as shown inFIGS. 33 to 35) joined through the flow channel inside the valve case32.

A positioning bolt53that engages a screw hole55aformed in the cover body55is disposed in the coupling flange17D of the branching pipe17C when the cover body55is lowered to a position in contact with the upper surface of the coupling flange17D; and the coupling flange17D and cover body55are secured and coupled in a watertight state by the securing bolt54, which is used in place of the removed positioning bolt53, when the mounting position of the cover body55on the coupling flange17D has been determined, as shown inFIG. 29. At this point, the operation for removing the positioning bolt53and the operation for securing the securing bolt54can be carried out using one or more of the plurality of operation recesses32J formed in the coupling flange17D.

The lower coupling tube part32C of the valve case32is externally mounted on the coupling flange17D of the branching pipe17C from the pipe axial center direction, whereby a large flow channel through which the fluid device E can pass with a size that corresponds to the coupling flange17D of the branching pipe17C can be ensured inside the valve case32. The structure of the pulling and securing means33can be simplified because the lower coupling tube part32C of the valve case32can be dually configured as a pulling member when the valve case32is pulled and secured to the coupling flange17C.

Additionally, when the coupling flange17D of the branching pipe17C and the fluid device E joined through the flow channel inside the valve case32are secured and coupled by the securing bolt54, which is mounted and operated from the lower end opening side of the lower coupling tube part32C of the valve case32, in a state in which the valve case32is pulled and secured to the coupling flange17C by the pulling and securing means33disposed in the lower coupling tube part32C of the valve case32, the securing bolt54can be readily fastened and operated in a simple orientation from the external side in the radial direction of the lower coupling tube part32C by way of the cutout-shaped operation recess32J formed in the lower coupling tube part32C, even when the opening end edge of the lower coupling tube part32C of the valve case32projects considerably further downward along the pipe axial center direction than the lower surface (rear surface) of the coupling flange17D.

In the lower coupling tube part32C of the valve case32, the thickness of a first peripheral wall portion32Ca, which includes the location in which the plurality of screw holes33B are formed and which is formed in the shape of a strip or substantially in the shape of a strip along the vertical direction (the pipe axial center direction), is configured to be greater than the thickness of a second peripheral wall portion32Cb, which includes the location in which the operation recess32J is formed and which is formed in the shape of a strip or substantially in the shape of a strip along the vertical direction. The inside surface of the first peripheral wall portion32Caof the lower coupling tube part32C and the inside surface of the second peripheral wall portion32Cbare formed as the internal peripheral surface having the same inside diameter; and the length in the circumferential direction of the second peripheral wall portion32Cbpositioned between adjacent first peripheral wall portions32Cais configured to be greater than the length of the operation recess32J in the circumferential direction.

For this reason, the first peripheral wall portion32Caof the lower coupling tube part32C in which the screw holes33B are formed is made thicker by the strip-form shape or substantially strip-form shape along the vertical direction, and even though the area for pulling and securing the valve case32to the coupling flange17C is robustly configured, the outside surface of the second peripheral wall portion32Cbis positioned further inward in the radial direction of the pipe than the outside surface of the first peripheral wall portion32Ca, and the length of the second peripheral wall portion32Cbin the circumferential direction is configured to be greater than the length of the operation recess32J in the circumferential direction. Therefore, the operation for fastening the securing bolt54through the operation recess32J can be readily carried out without interference from the thick first peripheral wall portion32Ca.

In this embodiment, the cutout depth of the operation recess32J is set to a depth in which a part of the head of the positioning bolt53and a part of the head of the securing bolt54can be seen from the outside through the operation recess32J in the radial direction of the pipe, but the cutout depth of the operation recess32J may be configured to a depth in which the entire head of the positioning bolt53and the head of the securing bolt54can be seen.

Furthermore, flow channel pressure adjustment means37for adjusting and equalizing the pressure of the upstream-side flow channel and the downstream-side flow channel of the valve element31is disposed in the sluice valve for operations D when the valve element31in the closed valve position is openably operated, as shown inFIGS. 6,7,11,12.

The flow channel pressure adjustment means37is configured having a first connection port37A formed in the upper coupling tube part32E of the valve case32, the first connection port37A being in communication with the downstream-side flow channel of the valve element31in the closed valve position; a second connection port37B formed in one sidewall facing the opening and closing movement pathway inside the valve case32, the second connection port37B being in communication with the upstream-side flow channel of the valve element31in the closed valve position; and a first on-off valve37F for opening and closing the flow channel between the two connection fittings37C,37D and a second on-off valve37G for discharging clean water inside the flow channel to the exterior are disposed in a pressure equalization hose37E, which is provided with the first connection fitting37C which connect to the first connection port37A in a watertight state, and the second connection fitting37D which can connect to the second connection port37B in a watertight state.

(4) The operations steps ofFIGS. 17 to 18show a step for coupling, in a watertight state, a casing27B of the drill27provided with a cylindrical rotary cutter (hole saw)27A, which is an example of a cutting tool, to the coupling flange32F formed on the upper part of the valve case32of the sluice valve for operations D; a step for sending the cylindrical rotary cutter27A of the drill27through the openably operated sluice valve for operations D and the branching pipe17C of the split T-shaped pipe17to form a circular through-hole16in the pipe wall of the water supply pipe1; a step for withdrawing the cylindrical rotary cutter27A into an accommodation space28after the through-hole16has been formed, and closeably operating the sluice valve for operations D; and a step for removing the drill27from the coupling flange32F of the sluice valve for operations D.

A coupling case27C capable of forming a storage space28for the cylindrical rotary cutter27A is disposed in the lower part of the casing27B of the drill27in the downstream-side flow channel (upper internal space) partitioned by the closeably operated valve element31in the valve flow channel (internal space) of the valve case32; and a coupling flange27D is formed in the lower part of the coupling case27C, the coupling flange27D being secured and coupled to the coupling flange32F of the sluice valve for operations D in a watertight state via a plurality of bolts8and nuts9, which is an example of fastening means.

(5) The operations steps ofFIGS. 19 to 21show a step for securing and coupling the flow channel cut-off apparatus40in a watertight state to the coupling flange32F of the two sluice valve for operations D, the two flow channel cut-off apparatuses40being provided with a valve element40A for stopping the flow of water supply into the renovation operations area W, and valve operation means40C for switching the valve element40A between an open flow channel position inside an operations case40B and a flow channel cut-off position in which the valve element40A has moved inside the water supply pipe1through the through-hole16formed in the pipe wall; a step for connecting the bypass piping41across the operations case40B of the flow channel cut-off apparatus40; a step for attaching a cut-off-confirming split T-shaped pipe46for confirming that the inflow of water supply to the connecting pipe4, which is a constituent member of the to-be-renovated pipeline assembly A, has been cut off; and a step for moving the valve element40A of the two flow channel cut-off apparatuses40into the flow channel cut-off position inside the water supply pipe1through the openably operated sluice valve for operations D and the branching pipe17C of the split T-shaped pipe17, and through the through-hole16of the water supply pipe1to cut off two locations at the two ends of the renovation operations area W of the water supply pipe1, so that the two pipe parts of the water supply pipe1positioned at the two ends of the renovation operations area W are placed in communication via the two operations cases40B, the branching pipe17C of the split T-shaped pipe17, and the bypass piping41.

A coupling flange40D that is secured and coupled in a watertight state to the coupling flange32F of the sluice valve for operations D via a plurality of bolts8and nuts9as an example of the fastening means is formed on the lower end of the operations case40B of the flow channel cut-off apparatus40; and a storage space42that is capable of accommodating the valve element40A is formed by the internal space of the operations case40B and the downstream-side flow channel (upper internal space) partitioned by the closeably operated valve element31in the valve flow channel (internal space) of the valve case32.

Conventionally, various structures have been proposed as the valve operation means40C of the flow channel cut-off apparatus40, and in this embodiment, an elevating operation shaft44coupled to the valve element40A is elevatably passed through and supported by in a watertight state an elevating guide member43disposed in a ceiling wall part40bof the operations case40B; and a jacking mechanism (not shown) for pressing the valve element40A into the flow channel cut-off position against the water pressure is disposed between the operations case40B and an operation rod45, which is disposed at the upper end of the elevating operation shaft44.

Also, the operation rod45of the elevating operation shaft44is lifted by a crane or the like in the case that the valve element40A in a flow channel cut-off position is to be elevated to the open flow channel position inside the operations case40B.

In the step for connecting the bypass piping41across the operations case40B of the two flow channel cut-off apparatuses40, the bypass piping41spanning the two operations cases40B is configured by sequentially connecting an on-off valve48, an elbow49, a polyethylene pipe or another straight pipe50, and a collar51for connecting together the ends of the straight pipe50, to a connecting pipe47disposed in the two operations cases40B, as shown inFIG. 21.

The cut-off-confirming split T-shaped pipe46is composed of an arcuate divided joint body46A divided into three parts in the circumferential direction, and a connecting pipe part46C provided with an on-off valve46B is projectingly formed on the divided joint body46A positioned on the upper side.

Next, when the cut-off-confirming split T-shaped pipe46is externally mounted and secured to the connecting pipe4, a coupling flange52A of a small drill52is secured and coupled in a watertight state to a coupling flange46D at the distal end side of the connecting tube part46C of the cut-off-confirming split T-shaped pipe46; and a cutting tool of the drill52is sent through the openably operated on-off valve46B of the cut-off-confirming split T-shaped pipe46and the connecting tube part46C to form a through-hole in the pipe wall of the connecting pipe4, as shown inFIG. 19.

The valve elements40A of the two flow channel cut-off apparatuses40are switchably operated to the flow channel cut-off position in which the valve elements40A are moved inside the water supply pipe1through the through-hole16formed in the pipe wall to stop the inflow of water supply to the renovation operations area W, and the on-off valve46B of the cut-off-confirming split T-shaped pipe46is openably operated to check for the existence of water supply leakage.

At this point, a flow channel having a suitable size is ensured between the rear surface of the valve element40A in the flow channel cut-off position and the internal peripheral surface of the through-hole16of the water supply pipe1. Therefore, the two pipe parts of the water supply pipe1positioned at the two ends of the renovation operations area W are placed in communication via the branching pipe17C of the split T-shaped pipe17, the two operations cases40B, and the bypass piping41when the two on-off valves48of the bypass piping41are openably operated.

(6) The operations step ofFIG. 22shows a step for separating and removing the to-be-renovated pipeline assembly A in the renovation operations area W of the water supply pipe1, which constitutes a part of the circulatory piping system.

At this point, in this embodiment, a part of one of the water supply pipes1and a part of the other water supply pipe1are cut by a pipe cutting apparatus (not shown), and the to-be-renovated pipeline assembly A is separated and removed from the water supply pipe1. Therefore, the entire length L of the to-be-renovated pipeline assembly A is a dimension that includes the cut pipe parts of the two water supply pipes1.

After the flow channel has been cut off by the valve element40A of the flow channel cut-off apparatus40disposed in two locations at the two ends of the renovation operations area W in the water supply pipe1, and the flow of water supply to the renovation operations area W has been stopped, there is dislocating movement force toward the relative approaching side in the pipe axial center direction of the two remaining pipe parts1A,1B in which water supply pressure is acting via the valve element40A of the flow channel cut-off apparatus40when the to-be-renovated pipeline assembly A in the renovation operations area W has been separated and removed, and the dislocating movement force is propagated from mutually opposite directions in relation to the rigid installation base15(two H-shaped steel sections) from the pipe holders18and the split T-shaped pipe17secured to the remaining pipe parts1A,1B, whereby the dislocating movement in the pipe axial center direction of the two remaining pipe parts1A,1B in which water supply pressure is acting can be effectively counterbalanced using the opposing remaining pipe part1A or1B of the counterpart side.

When the to-be-renovated pipeline assembly A in the renovation operations area W of the water supply pipe1is to be separated, the bolts8and nuts9that secure and couple together the pressing ring7externally mounted on one of the water supply pipes1and the coupling flange2A of one end of the short pipe2are unfastened, the bolts8and nuts9that secure and couple together the pressing ring7externally mounted on the connecting pipe4and the coupling flange5A of one end of the collar5are unfastened, and the bolts8and nuts9that secure and couple together the pressing ring7externally mounted on the other water supply pipe1and the coupling flange5A of the other end of the collar5are unfastened. The collar5is thereafter slidably moved to the connecting pipe4side, the to-be-renovated pipeline assembly A is moved to the other water supply pipe1side, and one of the water supply pipes1and the short pipe2are unfitted, whereby the to-be-renovated pipeline assembly A can be separated from the water supply pipe1without cutting.

(7) The operations steps ofFIGS. 23 to 25show a step for connecting the new pipeline assembly B to the two remaining pipe parts1A,1B of the water supply pipe1after removal.

The new pipeline assembly B is composed of a cast-iron short pipe2fittably connected in a watertight state to an end part of one of the cast-iron water supply pipes1, a sluice valve3that is flange-joined in a watertight state to the other end part of the short pipe2, a cast-iron connecting pipe4that is flange-joined in a watertight state to the other end part of the sluice valve3, and a collar5that connects in a watertight state the other end part of the connecting pipe4and the end part of the other cast-iron water supply pipe1.

The new pipeline assembly B arranged in a coaxial state facing the two remaining pipe parts1A,1B of the water supply pipe1after removal is moved to one water supply pipe1side, the receiving mouth of the short pipe2is fittably connected to the one remaining pipe part1A of the water supply pipe1, and the pressing ring7externally mounted on the water supply pipe1and the coupling flange2A of one end of the short pipe2are fastenably secured by bolts8and nuts9, or other fastening means, in a state in which the packing6interposed between the tapered internal peripheral surface2aon the receiving mouth side of the short pipe2and the external peripheral surface of one of the water supply pipes1, whereby the packing6is compressed to a watertight state by the pressing ring7.

Next, the collar5is slidably operated to a position for fittably connecting to the remaining pipe part1B of the other water supply pipe1; the pressing ring7externally mounted on the connecting pipe4and the coupling flange5A of one end of the collar5are thereafter fastenably secured by bolts8and nuts9, or other fastening means, in a state in which the packing6is interposed between the tapered internal peripheral surface5aof one end of the collar5and the external peripheral surface of the connecting pipe4; and the pressing ring7externally mounted on the other water supply pipe1and the coupling flange5B of the other end of the collar5are fastenably secured by bolts8and nuts9, or other fastening means, in a state in which the packing6is interposed between the tapered internal peripheral surface5bof the other end of the collar5and the external peripheral surface of the other water supply pipe1. The packing6is thereby compressed to a watertight state by the pressing ring7.

(8) The operations steps inFIGS. 26 to 29show a step for switching the valve element40A of the two flow channel cut-off apparatuses40from a flow channel cut-off position to an open flow channel position after the new pipeline assembly B has been connected, closeably operating the sluice valve for operations D, and removing the flow channel cut-off apparatus40from the coupling flange32F of the sluice valve for operations D; a step for securing and coupling, in a watertight state, a cover-mounting apparatus56on the coupling flange32F of the sluice valve for operations D, the cover-mounting apparatus56being provided with a cover body (an example of the fluid device E joined with the coupling flange17D of the branching pipe17C through the flow channel inside the valve case32of the sluice valve for operations D)55capable of sealing off the opening of the branching pipe17C of the split T-shaped pipe17; a step for attaching the cover body55of the cover-mounting apparatus56to the coupling flange17D of the branching pipe17C of the split T-shaped pipe17through the openably operated sluice valve for operations D; a step for removing the cover-mounting apparatus56from the coupling flange32F of the sluice valve for operations D and furthermore removing the sluice valve for operations D from the coupling flange17D of the split T-shaped pipe17; and a step for removing the installation base15and the two pipe holders18from the work pit P.

A coupling flange56B that is secured and coupled in a watertight state to the coupling flange32F of the sluice valve for operations D via a plurality of bolts8and nuts9as an example of the fastening means is formed on the lower end of an operations case56A of the cover-mounting apparatus56; and an accommodation space57capable of storing the cover body55is formed by the internal space of the operations case56A and the downstream-side flow channel (upper internal space) partitioned by the closeably operated valve element31in the valve flow channel (internal space) of the valve case32.

The positioning bolt53is disposed in the coupling flange17D of the split T-shaped pipe17, and the positioning bolt53engages the screw hole55aformed in the cover body55when the cover body55is lowered to a position in contact with the upper surface of the coupling flange17D of the split T-shaped pipe17. The coupling flange32F and the cover body55are secured and coupled together in a watertight state by the securing bolt54, as shown inFIG. 29, when the mounting position of the cover body55in relation to the coupling flange32F has been confirmed.

Conventionally, various structures have been proposed as elevating operation means56C for switching the cover body55between a standby position inside the operations case56A and a cover-mounted position in contact with the upper surface of the coupling flange17D of the split T-shaped pipe17, and in this embodiment, an elevating operation shaft60coupled to a cover-holding member59for detachably holding the cover body55is elevatably passed through and made to support in a watertight state an elevating guide member58disposed in a ceiling wall part56aof the operations case56A; and a jacking mechanism (not shown) for pressing the cover body55into the cover-mounted position against the water pressure is disposed between the operations case56A and an operation rod61, which is disposed at the upper end of the elevating operation shaft60.

Also, the operation rod61of the elevating operation shaft60is lifted by a crane or the like in the case that the cover-holding member59in the cover-mounted position is to be elevated to the standby position inside the operations case56A.

(9) The operations step ofFIG. 30is a step for building an auxiliary support structure in the case that there is a possibility that the pipeline constituent members in the renovation operations area W of the water supply pipe1facing the work pit P will bend and deform under their own weight; and filling the work pit P after the support structure has been built.

The step for building a support structure is omitted and the work pit P is filled in when there is no possibility that the pipeline constituent members in the renovation operations area W of the water supply pipe1will bend and deform under their own weight, or when the amount of bending deformation is low and there is no need to provide support.

As an example of the steps for building a support structure, in this embodiment, the method comprises a step for building a concrete strut62and for supporting the lower surface of the split T-shaped pipe17, on the operations bottom surface of the work pit P; and a step for building a concrete strut63for supporting the lower surface of the sluice valve3, on the operations bottom surface of the work pit P.

It is possible to use steel, wood, or other rectangular material in place of the two concrete struts62,63.

In this embodiment, the renovation method is a method in which the to-be-renovated pipeline assembly A that constitutes a part of a circulatory piping system of the piping system for a water supply pipe, which is an example of a fluid pipe, is replaced by a new pipeline assembly B. Therefore, the two remaining pipe parts1A,1B of the water supply pipe1from which the to-be-renovated pipeline assembly A has been separated and removed are filled with water supply (clean water) even without the bypass piping41being disposed.

However, bypass piping41for maintaining the flow of water supply must be disposed in the case that a plurality of locations of the circulatory piping system are cut off due to construction.

Bypass piping41is not required to be disposed in the case of renovation construction that does not cause a problem when the fluid is temporarily cut-off (water stoppage) in a piping system through which a fluid is flowing in a single direction.

In this case as well, when the flow channel has been cut off by the valve element40A of the flow channel cut-off apparatus40disposed in two locations at the two ends of the renovation operations area W in the fluid pipe (water supply pipe)1to stop the inflow of fluid into the renovation operations area W, and the to-be-renovated pipeline assembly A in the renovation operations area W has thereafter been separated and removed, there is a dislocating movement force in the pipe axial center direction of the upstream-side remaining pipe part1A to which fluid pressure is being applied via the upstream-side valve element40A, and the dislocating movement force is propagated from one of the split T-shaped pipes17and the pipe holders18secured to the upstream-side remaining pipe part1A to the rigid installation base15(two H-shaped steel sections), and is further propagated from the installation base15to the downstream-side remaining pipe part1B via the other split T-shaped pipe17and the pipe holder18secured to the downstream-side remaining pipe part1B, whereby the dislocating movement in the pipe axial center direction of the upstream-side remaining pipe part1A to which fluid pressure is being applied can be effectively counterbalanced using the opposing downstream-side remaining pipe part1B.

Second Embodiment

FIGS. 31 and 32show another embodiment of the pressing means35for imparting downstream-side pressing movement force to the other surface on the upstream side of the valve element31in a closed-valve position, and pressing the O-ring34mounted in the seal holding groove31bof the valve element31against the valve seat32I inside the valve case32.

The pressing means35is configured so that a second bearing part32L that projects outward in a state passing through the valve case32in the vertical direction is formed on the lower wall facing the opening and closing movement pathway of the valve element31inside the valve case32and in an area that faces the two sliding parts31A of the valve element31in a closed valve position; and a bushing35F that communicably forms a mounting hole35aand a screw hole35bthat opens inside the valve case32is fastenably secured to the second bearing part32L by a locking screw35G in a state of having been inserted from the lower side.

A lift shaft35H capable of lifting the lower surface of the two sliding parts31A of the valve element31is elevatably mounted in the mounting hole35aof the bushing35F; and an elevating operation screw35I for elevatably operating the lift shaft35H mounted in the mounting hole35ais threaded into the screw hole35bof the bushing35F.

The elevating operation screw35I is threadably operated and can thereby be made to change between a non-pressing state in which the upper end of the lift shaft35H is set at a distance below the lower surface of the two sliding parts31A of the valve element31, and a pressing state in which the lift shaft35H is elevatably moved to a closed-valve position in which the O-ring34mounted in the seal holding groove31bof the valve element31is pressed against the valve seat32I of the valve case32in a watertight state.

An O-ring35J for providing a watertight seal with the internal peripheral surface of the second bearing part32L is mounted in the seal-holding groove formed in one location in the external peripheral surface of the bushing35F; and O-rings35K for providing a watertight seal with the external peripheral surface of the lift shaft35H are mounted in the seal-holding grooves formed in two locations in the internal peripheral surface of the bushing35F.

The configuration is otherwise the same as the configuration described in the first embodiment above. Therefore, the same reference numerals as those of the first embodiment are used for the same constituent locations and a description thereof is omitted.

Third Embodiment

FIGS. 33 to 36show the latter half of the step of the method for forming a through-hole16as the valve insertion port in a specific location (sluice valve installation location) of the water supply pipe, which is an example of the fluid pipe, in a state of nonstop water supply in which the flow of water supply (clean water) is maintained, and installing a sluice valve F (an example of the fluid device E joined with the coupling flange17D of the branching pipe17C through the flow channel inside the valve case32of the sluice valve for operations D) provided with a sluice valve element70for closing (cutting off) the flow channel of the water supply pipe1through the through-hole16. The first half of the step up to forming the through-hole16in the pipe wall of the water supply pipe1is described with reference to theFIGS. 5 and 18of the first embodiment.

(1) A split T-shaped pipe17(the shape and number of divisions is slightly different from the split T-shaped pipe17described in the first embodiment, but the structure and function are substantially the same; therefore, the same reference numerals as those used in the description of the first embodiment are used and a description thereof is omitted) divided into three parts in positions along the horizontal plane that passes near or through the pipe axial center of the water supply pipe1is externally mounted and secured in the sluice valve installation location of the water supply pipe1, as an example of the pipe joint provided with a branching pipe17C in an area that corresponds to the through-hole16formed in the pipe wall of the water supply pipe1.

When the step for attaching the split T-shaped pipe17is completed, a flange cover (not shown) for sealing the upper opening of the branching pipe17C in a watertight state is attached to the coupling flange17D of the upper end of the branching pipe17C, and water is injected at a pressure that corresponds to water supply pressure into the internal space between the internal peripheral surface of the split T-shaped pipe17and the external peripheral surface of the water supply pipe1to carry out a water pressure test in order to check for the existence of leaks.

When the step for testing water pressure is completed, the valve case32of the sluice valve for operations D (the structure is the same as that of the sluice valve for operations D described in the first embodiment; therefore, the same reference numerals as those used in the description of sluice valve for operations D of the first embodiment are used and a description thereof is omitted) provided with the valve element31, which is openably and closeably actuated in the horizontal direction by the rotation operation of the valve operation means30, is secured and coupled in a watertight state to the coupling flange17D in the branching pipe17C of the split T-shaped pipe17.

(2) Next, the casing27B of the drill27provided with the cylindrical rotary cutter (hole saw)27A as an example of a cutting tool is secured and coupled in a watertight state to the coupling flange32F formed on the upper part of the valve case32of the sluice valve for operations D. A cylindrical rotary cutter27A of the drill27is sent through the openably operated sluice valve for operations D and the branching pipe17C of the split T-shaped pipe17to form a circular through-hole16in the pipe wall of the water supply pipe1. The cylindrical rotary cutter27A is withdrawn into the accommodation space28and the sluice valve for operations D is thereafter closeably operated. The drill27is then removed from the coupling flange32F of the sluice valve for operations D.

(3) As shown inFIG. 33, an externally-threaded screw part formed on the bearing part72aon the upper end of the valve case72of the sluice valve F is threadably coupled to an internally-threaded screw part of a suspended coupling member71D attached to the lower end of an elevating operation shaft71B of an operations case71provided with a coupling flange71A secured and coupled in a watertight state to the coupling flange32F of the sluice valve for operations D via a plurality of the bolts8and nuts9as an example of fastening means, and an elevating guide member71C that passes through and elevatably supports the elevating operation shaft71B in a watertight state. The operations case71in which the sluice valve F is assembled is thereafter suspendably transported above the sluice valve for operations D by a crane or the like, and the coupling flange71A of the operations case71and the coupling flange32F of the sluice valve for operations D are secured and coupled in a watertight state.

The valve case72is composed of a valve case main body72A and a valve cover72B, the valve case main body72A having a coupling flange72bthat is formed on the lower end and that is secured and coupled in a watertight state to the coupling flange17D of the split T-shaped pipe17by the securing bolt54, and the valve cover72B being secured and coupled in a watertight state to a coupling flange72cformed on the upper end of the valve case main body72A. A valve stem73of the sluice valve element70is passed through and supported in a watertight state by the bearing part72aof the valve cover72B.

(4) As shown inFIG. 34, a jacking mechanism (not shown) for pressing the valve case72of the sluice valve F and the sluice valve element70into a predetermined mounted position against the water pressure is disposed between the operations case71and an operation rod74, which is disposed at the upper end of the elevating operation shaft71B, after which the sluice valve for operations D is openably operated. The jacking mechanism is elevatably operated to lower the lower coupling flange72bof the valve case72inside the operations case71through the internal flow channel of the sluice valve for operations D to a position in contact on the coupling flange17D of the split T-shaped pipe17.

A positioning bolt53that engages a screw hole72dformed in the lower coupling flange72bof the valve case72is disposed in the coupling flange17D of the split T-shaped pipe17, and at this point the mounting position of the valve case72in relation to the coupling flange17D of the split T-shaped pipe17is automatically corrected and fixed in a predetermined mounting position by the positioning guidance effect of the positioning bolt53.

When the mounting position of the valve case72in relation to the coupling flange17D of the split T-shaped pipe17has been fixed, the positioning bolt53is removed and replaced by the securing bolt54to secure and couple the coupling flange17D and the valve case72in a watertight state, as shown inFIG. 35. At this point, the operation for removing the positioning bolt53and the operation for securing the securing bolt54are carried out using one or more of a plurality of operation recesses32J formed in the coupling flange17D.

When the coupling flange17D and the valve case72have been secured and coupled, the operations case71is removed from the coupling flange32F of the sluice valve for operations D and the sluice valve for operations D is removed from the coupling flange17D of the split T-shaped pipe17.

Fourth Embodiment

FIGS. 36 to 41show another embodiment of the sluice valve for operations D. An operation recess32J in a shape of a cutout is formed between adjacent screw holes33B of the pulling and securing means33in the lower coupling tube part32C of the valve case32, the operation recess32J being used for operating the securing bolt (an example of a fastener)54from the lower surface (rear surface) of the coupling flange17D, and the securing bolt54being used for securing and coupling the fluid device E (e.g., the cover body55capable of sealing the opening of the branching pipe17C of the split T-shaped pipe17in a watertight state, as shown inFIGS. 27 and 28; or the valve case72of the sluice valve F, as shown inFIGS. 33 to 35) that is joined with the coupling flange17D of the branching pipe17C through the flow channel inside the valve case32. The two inside corners of the operation recesses32J are arcuately formed.

The configuration is otherwise the same as the configuration described in the first embodiment above. Therefore, the same reference numerals as those of the first embodiment are used for the same constituent locations and a description thereof is omitted.

Other Embodiments

(1) In the embodiments described above, the pulling and securing means33is configured so that the bolt33A is threaded from the outer side in the radial direction of the pipe into the screw hole33B formed in a plurality of locations in the circumferential direction of the lower coupling tube part32C of the valve case32, the bolt33A being provided with a tapered pressing surface33athat is in contact from the horizontal direction with the tapered surface17dformed on the external peripheral edge of the lower surface (rear surface) of the coupling flange17D. However, no limitation is imposed by this configuration, and it is also possible to pull and secure the valve case32to the coupling flange17D using a cam mechanism, a screw mechanism, or other pulling and securing means.

(2) In the embodiments described above, the branching pipe17C of the split T-shaped pipe17externally mounted and secured on the water supply pipe1is used as an example of the connecting pipe, but the connecting pipe may be a branching pipe that is integrally formed with the water supply pipe1, or may be the pipe end part of the water supply pipe.

In other words, the connecting pipe may be a connecting pipe that is provided with a coupling flange on which the coupling tube part32C of the valve case32can be externally mounted from the pipe axial center direction.

(3) In the embodiments described above, the valve case32is bisected so as to allow separation in a position that traverses in the crosswise direction the two sliding parts31A of the valve element31in the open valve position, but it is also possible to divide the valve case32into three parts or more, and to configure the opening of at least one of the divided valve case bodies to be an opening that allows the valve element31to be removed to the exterior.

(4) In the embodiment described above,

An operation recess32J is formed in a plurality of locations in the circumferential direction of the lower coupling tube part32C of the valve case32, the operation recess32J being used for threadably operating the securing bolt54from the lower surface (rear surface) of the coupling flange17D, and the securing bolt54being an example of a fastener for securing and coupling the fluid device E that is joined with the coupling flange17D of the branching pipe17C through the flow channel inside the valve case32. However, the operation recess32J may be formed in an area that corresponds to the arrangement location of the securing bolt54.

The number of operation recesses32J may be lower than the arranged number of securing bolts54in the case that the operation recess32J is of considerable length in the circumferential direction.

INDUSTRIAL APPLICABILITY

The present invention can be applied to a sluice valve for operations that is mainly used in the case that, e.g., a cover body for sealing off an end part opening of a connecting pipe, or a valve case of a sluice valve or other fluid device is attached to a coupling flange formed on an end part of a branching pipe or another connecting pipe while the flow of a fluid in the pipe is maintained.

REFERENCE SIGNS LIST