JP4594641B2 - Valve replacement method for fluid piping system - Google Patents

Description

The present invention relates to an improvement in a valve replacement method for a butterfly valve connected to a fluid pipe of a fluid piping system such as a water pipe.

When the butterfly valve connected to the fluid pipe of the fluid piping system is inoperable while being operated to the valve closing operation position, an opening for securing a flow path is made in the valve body at the valve closing operation position There is a need to.
In addition, when replacing the butterfly valve with another on-off valve, a method of closing the upstream flow path in a sealed state with a pipe closing device inserted through the downstream opening of the butterfly valve is conceivable. Due to the structure in which the disc-shaped valve body is supported so that it can rotate freely around the valve stem in the valve box, the valve body remains in the flow path even when it is fully opened, upstream of the butterfly valve. In order to insert the conduit closing device, it is necessary to make an opening for inserting the conduit closing device in the valve body at the valve closing operation position.

  As a method of drilling an opening for securing a flow path or an opening for inserting a conduit closing device in a valve body at a valve closing operation position, generally, a butterfly valve connected to a fluid pipe is used. A working on-off valve is connected to the downstream opening of the valve box, and the downstream opening of the working on-off valve is configured to have a cutting diameter smaller than the turning trajectory diameter of the inner ends of both valve rods of the butterfly valve. A through hole is formed in the valve body of the butterfly valve while maintaining the flow of the fluid in the fluid pipe by the hole saw of the drilling machine inserted from the downstream opening of the work on / off valve. A construction method is considered.

JP 2001-162422 A

  In the above-described valve body cutting method, the minimum diameter of the turning trajectory of a connecting member such as a taper pin that fixedly connects the valve body of a butterfly valve made of a soft material (for example, FCD450) to both valve stems. Although the through hole is formed in the central portion of the valve body that is more radially inward and simple in shape, it is possible to improve the efficiency and ease of drilling work, but it is formed in the valve body. Since the inner diameter of the through hole is smaller than the turning trajectory diameter of the inner ends of both valve rods, in the case of securing the flow path, the opening flow path area of the through hole is reduced, and the butterfly valve In the case of replacement, the diameter expansion deformation required for the elastic sealing portion of the pipe closing device that passes through the through hole of the valve body becomes large, which leads to complication of the entire pipe closing device and an increase in manufacturing cost. There's a problem.

  Further, when the diameter of the hole saw of the drilling machine is slightly increased so that the cutting edge of the hole saw is applied to both connecting members for fixedly connecting the valve body and both valve stems, both connecting members are made of a material harder than the valve body ( For example, it is made of SUS304) and is long along the feeding axis direction which is the traveling direction of the hole saw of the drilling machine at the time of the valve closing operation, and has a tapered shape. There is a problem that it becomes easy to cause damage or biting of the machine hole saw.

The present invention was made in view of the circumstances described above, a main object thereof may efficiently the drilling operation for the butterfly valve, in that it provides a valve replacement method of the fluid piping system which can be easily performed is there.

According to a first characteristic configuration of the present invention, a working on / off valve is connected to a downstream opening of a valve box of a butterfly valve connected to a fluid pipe, and the butterfly valve is connected to a downstream opening of the working on / off valve. A drilling machine equipped with a drilling machine equipped with a hole saw configured to have a cutting diameter larger than the maximum diameter of the connecting member for fixedly connecting the valve body and both valve stems, and inserted from the downstream opening of the work on-off valve With the hole saw of the butterfly valve, the valve rod part located radially outward from the pivot trajectory of the connecting member is cut with a hole saw while maintaining the flow of fluid in the fluid pipe. Alternatively, after removing together with most of the valve body, the upstream side flow path from the place where the butterfly valve is installed is sealed by a pipe closing device inserted upstream through the flow path in the cut and removed butterfly valve. Closed, butterfly valve and While it replaced with another opening and closing valve by removing the work-off valve, in that characterized by removing the pipe closure apparatus from the downstream side opening of the closing valve.

  According to the above characteristic configuration, the working on-off valve is connected to the downstream opening of the valve box of the butterfly valve connected to the fluid pipe, and the drilling machine is attached to the downstream opening of the on-off valve. If the hole saw of the machine is driven to rotate and sent to the butterfly valve through the work on-off valve, the cutting diameter of this hole saw is larger than the maximum diameter of the turning trajectory of the connecting member that fixedly connects the valve body and both valve stems. Due to the large construction, the valve stem is cut through the radially outward side of the pivotal trajectory of the long connecting member along the feed axis of the hole saw during the valve closing operation. Since a part of the body or a part of the valve box is cut, the whole valve body or most of the valve body can be removed together with the cut valve rods.

  Next, the flow path upstream from the place where the butterfly valve is installed is sealed by the pipe closing device inserted upstream through the original flow path in the valve box from which the valve body or most of the valve body has been removed. In this state, the butterfly valve and the working on-off valve are removed and replaced with another on-off valve, and then the pipe closing device is removed from the downstream opening of the on-off valve.

  Therefore, the entire valve body of the butterfly valve or most of the butterfly valve can be removed while maintaining the flow of the fluid in the fluid pipe, so that a sufficient cross-sectional area of the butterfly valve can be ensured. Even in the case of replacement, the diameter expansion deformation required for the elastic sealing part of the pipe closing device inserted upstream of the butterfly valve is reduced, and the entire pipe closing device is simplified and the manufacturing cost is reduced. Can do. In addition, since the hole saw does not cut the connecting member that is long in the feeding axis direction, the efficiency and ease of the drilling operation can be achieved.

According to a second characteristic configuration of the present invention, in a fluid piping system in which a butterfly valve is attached to a branch pipe portion of a fluid pipe, a working on-off valve is connected to the downstream opening of the valve box of the butterfly valve. A drilling machine equipped with a hole saw having a cutting diameter larger than the maximum diameter of the rotation trajectory of the connecting member for fixedly connecting the valve body of the butterfly valve and both valve rods to the downstream opening of the on-off valve The hole saw of the drilling machine inserted and inserted from the downstream side opening of the work on / off valve, while maintaining the fluid flow in the fluid pipe, out of the pivot trajectory of the connecting member of both valve stems of the butterfly valve After the valve stem portion located at is cut with a hole saw and removed together with the valve body or most of the valve body, the butterfly valve is inserted into the butterfly valve through the flow path in the cut and removed butterfly valve. From the installation location The upstream flow path is closed in a sealed state, the butterfly valve and the working on / off valve are removed and replaced with another on / off valve, and the pipe closing device is removed from the downstream opening of the on / off valve. It is in the point to.

  According to the above characteristic configuration, the working on / off valve is connected to the downstream opening of the butterfly valve attached to the branch pipe of the pipe joint, and the drilling machine is attached to the working on / off valve. When the hole saw is driven to rotate and sent to the butterfly valve through the working on-off valve, the hole diameter of the hole saw becomes larger than the maximum diameter of the pivotal trajectory of the connecting member that fixedly connects the valve disc and both valve stems. Therefore, when the valve is closed, the valve stem is cut through the radially outward side of the rotation trajectory of the long connecting member along the feed axis of the hole saw, and depending on the cutting diameter of the hole saw, Since a part or a part of the valve box is cut, the entire valve body or most of the valve body can be removed together with the cut valve stems.

  Next, the flow path in the branch pipe portion of the pipe joint located upstream from the installation location of the butterfly valve by the pipe closing device inserted upstream through the original flow path in the valve box from which the valve element has been removed In this state, the butterfly valve and the working on / off valve are removed and replaced with another on / off valve, and then the pipe closing device is removed from the downstream opening of the on / off valve.

  Therefore, the entire valve body of the butterfly valve or most of the butterfly valve can be removed while maintaining the flow of the fluid in the fluid pipe, so that a sufficient cross-sectional area of the butterfly valve can be ensured. Even in the case of replacement, the diameter expansion deformation required for the elastic sealing part of the pipe closing device inserted upstream of the butterfly valve is reduced, and the entire pipe closing device is simplified and the manufacturing cost is reduced. Can do. In addition, since the hole saw does not cut the connecting member that is long in the feeding axis direction, the efficiency and ease of the drilling operation can be achieved.

According to a third characteristic configuration of the present invention, the cutting diameter of the hole saw is set to an outer diameter that is substantially the same as or larger than the outer diameter of the valve body. The valve stem portion located outside is cut by a hole saw.

  According to the above characteristic configuration, when the hole saw of the drilling machine is fed to the butterfly valve while being driven to rotate, the cutting diameter of the hole saw is configured to have an outer diameter substantially the same as or larger than the outer diameter of the valve body. Therefore, when the valve stem is cut through the radially outward side of the rotation trajectory of the long connecting member along the feed axis of the hole saw during the valve closing operation, the valve body is not cut or part of the outer peripheral side Therefore, the efficiency and ease of drilling can be promoted.

According to a fourth characteristic configuration of the present invention, the first locking means for locking one valve rod of the butterfly valve or the valve operating tool connected to the butterfly valve at the valve closing operation position is operated in a locked state before cutting by the hole saw. In addition, the second locking means for locking the other valve rod of the butterfly valve at the valve closing operation position is configured to be operated in the locked state.

  According to the above characteristic configuration, the both valve means can fix the one valve rod of the butterfly valve or the valve operating tool connected thereto and the other valve rod together at the valve closing operation position. It is possible to suppress the occurrence of cutting failure, cutting piece recovery failure, and the like due to the rotation of the valve body.

According to a fifth feature of the present invention, the inner peripheral wall surface portion on the downstream opening side that is smaller in diameter than the outer diameter of the valve body is cut out of the inner peripheral wall surface of the valve box of the butterfly valve when cutting with the hole saw. It is in the point comprised so that cutting and removal may be carried out.

  According to the above characteristic configuration, in order to guide the rotation of the valve body of the butterfly valve around the shaft axis, the inner peripheral wall surface portion on the downstream opening side of the valve box has a smaller diameter than the outer diameter of the valve body. Even if it is formed, the valve box itself is softer than the connecting member, so the inner peripheral wall surface part protruding inward can be easily cut and removed with a hole saw, and the efficiency of drilling work is improved. While facilitating simplification, a sufficient cross-sectional area of the flow path inside the butterfly valve can be secured.

According to a sixth characteristic configuration of the present invention, when the valve body is in the valve closing operation position, the first lock means opposes the valve box and the boss portion of the valve operating tool connected to one valve rod. The second lock means is configured to be locked by inserting a lock pin through a lock hole formed in communication with the part, and the second lock means has an end of another valve stem protruding outward from the outer surface of the valve box. It is in the point comprised so that it may lock by driving a wedge member between the part and the outer surface part of the valve box which opposes it.

  According to the above characteristic configuration, during the cutting preparation work, the lock pin is inserted into the lock hole formed in communication with the valve box and the boss portion of the valve operating tool connected to the one valve stem side, from the outer surface of the valve box. By driving the wedge member between the end portion of the other valve rod protruding outward and the outer surface portion of the valve box opposite thereto, the valve body can be firmly locked at the valve closing operation position. It is possible to satisfactorily suppress the occurrence of cutting failure and cutting piece collection failure due to the rotation of the valve body during cutting, and the locking operation for that purpose can be performed efficiently and reliably.

[First Embodiment]
FIG. 1 shows a pipe connection structure in the middle of a fluid piping system. A connecting flange portion 2A of a branch pipe portion 2 integrally formed in the middle of a water pipe 1 made of cast iron pipe, which is an example of a fluid pipe, is connected to a connecting flange portion 2A. The connecting pipe 4 provided with both ends 4A and 4B, the butterfly valve V provided with the valve box 10 formed with the connecting flanges 10A and 10B at both ends, and the connecting flange part as an example of fluid equipment or piping material The air valve 3 provided with 3A is fixedly connected in a detachable manner in a sealed state via bolts 6 and nuts 7 in this order.

  FIG. 2 shows a pipe connection structure when it is necessary to replace the butterfly valve V for reasons such as failure or malfunction while maintaining the flow of clean water in the water pipe 1, and the downstream connection of the butterfly valve V The connecting flange portion 3A of the air valve 3 is removed from the flange portion 10B, and the downstream connecting flange portion 10B of the butterfly valve V is in a state where the flow path in the valve box is fully opened or substantially fully opened with respect to the branch axis Y. An upstream connection flange portion 5A of the work on / off valve 5 having a valve body 5C that can be slidably opened and closed along a direction orthogonal to each other is fixedly connected in a sealed state via a bolt 6 or the like so as to be detachable.

  As shown in FIGS. 3 to 8, the downstream connection flange portion 5 </ b> B of the work on / off valve 5 has a taper which is a connection member for fixedly connecting the valve body 11 of the butterfly valve V and the two valve rods 12 </ b> A and 12 </ b> B. A drilling machine A provided with a hole saw 23 configured to have a cutting diameter larger than the maximum diameter of the rotation trajectory of the pin 13, more specifically, a cutting diameter larger than the outer diameter of the valve body 11, and FIGS. As shown in FIG. 3, the valve body 11 and the valve rods 12A and 12B are partly cut and removed by the hole saw 23 and are inserted into the branch pipe portion 2 of the water pipe 1 through the flow path W in the butterfly valve V. The pipe closing device B that closes the flow path upstream of the installation location of the butterfly valve V in a sealed state by operation is configured to be selectively fixed and connected in a sealed state.

  As shown in FIG. 4, the butterfly valve V has a radial opening / closing pivot shaft in which the valve shaft bolts constituting the valve rods 12 </ b> A and 12 </ b> B pass through the branch axis Y on both radial sides of the peripheral wall of the valve box 10. Boss portions 11A and 11B formed at two radial positions of the valve body 11 are formed on the inner end portions of the valve shaft bolts 12A and 12B that are assembled on the core Z and face the flow path W in the valve box 10. The valve body is driven and fixed by driving the taper pin 13 across the connecting hole formed in communication with the one valve shaft bolt 12A and the boss portion 11A of the valve body 11 fitted on the valve shaft bolt 12A. 11 and one of the valve shaft bolts 12 </ b> A are configured so as to be freely rotatable around the opening / closing rotation axis Z.

  When the valve element 11 is in the valve closing operation position, the pin axis of the taper pin 13 is configured to be parallel to the direction of the branch axis Y that is the feed axis of the hole saw 23.

  A valve seat retainer 15 for retaining and fixing an O-ring 14 which is an example of a sealing material constituting the valve seat surface is attached to the upstream opening of the valve box 10, and the inner periphery of the valve box 10 is The wall surface 10a is formed in a partial spherical shape that slides and guides the opening / closing rotation around the opening / closing rotation axis Z of the valve body 11, and the opening diameter at the downstream opening of the partial spherical inner peripheral wall surface 10a is. The outer diameter of the valve body 11 is smaller.

  Of one of the valve shaft bolts 12A that is rotatable about the opening / closing rotation axis Z with respect to the peripheral wall of the valve box 10, the angular shaft portion 12a that protrudes outward from the outer surface of the valve box 10 includes a valve The boss part 16A of the valve operating tool 16 is secured to the screw shaft part 12b that is externally fitted in an integrally rotated state in which the operating tool 16 cannot rotate relative to each other and is continuously formed on the distal end side of the square shaft part 12a. A nut 17 to be fixed is screwed together, and the valve element 11 is provided by an inner shaft portion of the other valve shaft bolt 12B screwed and fixed along the opening / closing rotation axis Z to the peripheral wall of the valve box 10. The other boss portion 11B is rotatably supported.

  In addition, when the two valve shaft bolts 12A and 12B of the butterfly valve V are cut by the hole saw 23 of the punching machine A, one valve shaft bolt 12A has a rotational force toward the valve opening operation position side, and the other valve shaft bolt. Since the rotational force to the slack side acts on 12B, in this embodiment, as shown in FIG. 4, the first locking means 8 for locking the valve operating tool 16 of the butterfly valve V in the valve closing operation position, and the butterfly The second locking means 9 for locking the other valve shaft bolt 12B of the valve V at the valve closing operation position is provided, and the rotation of the one valve shaft bolt 12A to the valve opening operation position side or the other valve shaft bolt 12B is provided. It is possible to avoid the occurrence of a cutting failure due to the rotational force toward the slack side, a mistake in collecting the cut pieces, or a situation where the cutting is impossible due to the biting of the hole saw 23.

  When the valve body 11 is in the valve closing operation position, the first lock means 8 is a lock pin extending over the lock hole 8A formed in communication with the opposite portion between the valve box 10 and the boss portion 16A of the valve operating tool 16. The second locking means 9 includes a hexagonal head portion 12c of the other valve shaft bolt 12B that protrudes outward from the outer surface of the valve box 10 and the opposite to the second locking means 9. The wedge member 9A is driven between the outer surface portion of the valve box 10 to be locked.

  As shown in FIGS. 3 to 8, the punching machine A is driven by a driving part 21 such as an electric motor or an engine to rotate on a casing 20 and slidably drive in a branch axis Y direction. On the other hand, a driving rotational force and a feeding force are applied, and the hole saw 23 fixedly connected to the connecting flange portion 22 at the tip end portion of the driving rotating shaft 21 is fed through the flow path in the work on-off valve 5, thereby providing a water supply. Of the two valve shaft bolts 12A, 12B of the butterfly valve V while maintaining the fluid flow in the pipe 1, the valve body 11 is located on the radially outer side with respect to the rotational trajectory of the taper pin 13. The shaft portion (valve stem portion) located on the radially outer side from the outer peripheral edge of the rim is cut and removed together with the valve body 11.

  The hole saw 23 is configured by providing a center drill 23B protruding forward from the cutting tip of the cylindrical body 23A at the center position of the bottom wall portion of the cylindrical body 23A having a cutting tip 23a at the tip. At the same time, the front end of the casing 20 is fixedly connected to the downstream connecting flange 5B of the working on-off valve 5 through a plurality of bolts 6 and nuts 7 as an example of fastening means. The connecting flange portion 20A is integrally formed.

  In addition, the distance L between the cutting tip 23a of the cylindrical body 23A and the tip of the center drill 23B is regulated in relative movement in the diameter direction of both the valves 23B and 11 as the cutting of the valve body 11 by the center drill 23B progresses. Thereafter, the cutting tip 23a of the cylindrical body 23A is set to a dimension for cutting the downstream opening of the partial spherical inner peripheral wall surface 10a of the valve box 10.

  As shown in FIGS. 9 to 16, the pipe closing device B has a bottomed cylindrical shape including a connecting flange portion 25 </ b> A that can be connected in a sealed state to the downstream connecting flange portion 5 </ b> B of the work on-off valve 5. A cylindrical first operating shaft 26 that passes through the bottom wall portion 25B of the working case 25 in a sealed state so as to be slidable in the axial direction, and the inside of the first operating shaft 26 is an axial core. A second operating shaft 27 slidably penetrating in the direction is provided, and a branch flow path, that is, a branch pipe portion of the water pipe 1 is provided on the inner end side of the first operating shaft 26 and the second operating shaft 27. Blocking means C for shielding (blocking) the flow path in 2 and a large-diameter pipe wall portion upstream of the shielding portion by the blocking means C, that is, at the periphery of the branch port on the inner peripheral surface of the water pipe 1 A retaining means D provided with a pair of locking links 28 and 29 protruding while being bent into a diameter-enlarging posture that can be engaged with each other is provided. Together they have, are provided operating means E for operating through both operating shaft 26, 27 a closing means C and retaining means D from the outside.

Next, the closing means C of the conduit closing device B will be described.
As shown in FIGS. 9 and 10, the first pressing plate 30 is provided with an annular pressing surface 30 </ b> A and a hollow portion 30 </ b> B opening concentrically toward the tip side at the inner end of the first operating shaft 26. Is fitted and fixed, and on the inner end side of the second operating shaft 27, an annular pressing surface 31 </ b> A that opposes the pressing surface 30 </ b> A of the first pressing plate 30 in the axial direction and a hollow portion of the first pressing plate 30. A second pressing plate 31 having a cylindrical portion 31B that is slidably fitted to 30B from the axial direction is externally fitted so as to be slidable in the axial direction. A stopper nut 32 and a lock nut 33 for setting the maximum movement position of the second pressing plate 31 to the upstream side are screwed into a screw shaft portion 27 a formed on the inner end side of the second operation shaft 27. ing.

  The outer diameter of the first pressing plate 30 and the outer diameter of the second pressing plate 31 are the original ones in the butterfly valve V in which the working on-off valve 5 and the valve body 11 are removed from the storage chamber 25C in the working case 25. The branch pipe part 2 of the water pipe 1 is configured to have the smallest inner diameter in the branch system so that it can be taken in and out of the branch pipe part 2 of the water pipe 1 through the flow path and the connecting pipe 4. The outer diameter is smaller than the inner diameter.

  Further, the cylindrical portion 31B of the second pressing plate 31 is formed to have an outer diameter smaller than the inner diameter of the branch pipe portion 2 of the water pipe 1 in a non-pressurized state (natural state), and both pressing plates Due to the clamping pressure from the axial direction by the pressing surfaces 30A, 31A of 30, 31, the inner peripheral wall surface and both pressing plates are elastically deformed into an expanded diameter state in close contact with the inner peripheral wall surface of the branch pipe portion 2 of the water pipe 1. An elastic annular body 34 made of urethane rubber that shields between the outer peripheries of 30 and 31 is packaged.

  The elastic annular body 34 is configured in a cylindrical shape that can be externally attached in close contact with the cylindrical portion 31B of the second pressing plate 31, and its axial center portion 34a has a larger diameter than both axial direction end portions 34b. The outer peripheral surface of the large-diameter central portion 34a is formed as a partially spherical surface whose central position in the axial center direction protrudes most outward, and further, the outer peripheral side of the end surfaces of both small-diameter end portions 34b. The end surface portion is formed in an annular inclined surface that is inclined at a predetermined angle (30 degrees in the present embodiment) with respect to a vertical plane orthogonal to the axis.

  Each of the outer peripheral side end surface portion of the pressing surface 30 </ b> A of the first pressing plate 30 and the outer peripheral side end surface portion of the pressing surface 31 </ b> A of the second pressing plate 31 is against the outer peripheral annular inclined surface at both end surfaces of the elastic annular body 34. It is formed on an annular inclined pressing surface located closer to the axial center position of the elastic annular body 34 toward the outer side in the radial direction so as to be in close contact with the axial direction, and the pressing surface 30 </ b> A of the first pressing plate 30. On the outer peripheral edge side and the outer peripheral edge of the pressing surface 31A of the second pressing plate 31, annular presser portions 30C and 31C that can be fitted in contact with the outer peripheral surfaces of the axial end portions 34b of the elastic annular body 34 are formed. ing.

  When the elastic annular body 34 interposed between the pressing plates 30 and 31 is elastically deformed into a diameter-enlarged state by the clamping force from the axial direction by the pressing plates 30 and 31, the shaft of the elastic annular body 34 is used. Since both end portions 34b in the core direction are configured to have a small diameter, and the outer peripheral surface of the central portion 34a in the axial center direction is formed as a partial spherical surface whose central position in the axial center direction protrudes most outwardly, However, since the axial center portion 34a of the elastic annular body 34 is configured to have a larger diameter than both end portions 34b of the axial center, the expansion deformation amount of the elastic annular body 34 as a whole can be reduced. It can be secured sufficiently.

  Moreover, as shown in FIGS. 14 and 15, the diameter of the cylindrical elastic annular body 34 interposed between the pressing plates 30 and 31 is increased by the pinching force from the axial direction by the pressing plates 30 and 31. When elastically deformed to the state, the annular pressing portions 30C and 31C formed on the pressing plates 30 and 31 bite into the bulging portion of the elastic annular body 34 bulging radially outward from the axial direction. It is possible to reliably and strongly prevent the elastic annular body 34 from coming off due to the water pressure of the tap water flowing in the pipe 1.

Next, the retaining means D will be described.
As shown in FIGS. 9 and 10, the plate-shaped second member is provided such that the end portions of the downstream locking links 29 are pivotally connected to the three circumferential positions of the upstream end surface of the second pressing plate 31 so as to be swingable. One connecting piece 36 is fixed, and three upstream positions on the outer peripheral surface of the mounting cylinder 37 slidably fitted to the inner end side screw shaft portion 27a of the second operation shaft 27 are arranged on the upstream side. A plate-like second connecting piece 38, to which the end portion of the locking link 28 is pivotally connected in a swingable manner, is fixed, and the maximum movement position of the mounting cylinder 37 relative to the second operating shaft 27 to the upstream side A stopper nut 39 is set to the distal end side of the inner end side screw shaft portion 27 a of the second operation shaft 27.

  And among the 1st connection piece 36 of the 2nd press plate 31, and the 2nd connection piece 38 of the attachment cylinder 37, it covers three sets of 1st, 2nd connection pieces 36 and 38 which oppose each other in an axial direction. The pair of locking links 28 and 29 are pivotally connected to each other to slide the second operation shaft 27 toward the outer end side with respect to the first operation shaft 26 as shown in FIGS. In conjunction with this, the inner peripheral wall surface on the upstream side of the shielded portion by the elastic annular body 34, that is, the outer peripheral wall of the water pipe 1 is bent and bent so as to be able to be engaged with a diameter expanding posture. As shown in FIG. 10, when the pair of locking links 28 and 29 of the retaining means D are extended to the reduced diameter posture, the bending link connection point S2 of the locking links 28 and 29 is formed. The outer hips are bent in the radially outward direction, that is, the bent links 28 and 29 are connected to each other. S2 is a pivot connection point S1 of the upstream locking link 28 with respect to the second connection piece 38 of the mounting cylinder 37 and a pivot connection point of the downstream locking link 29 with respect to the first connection piece 36 of the second pressing plate 31. An inversion prevention means F is provided for restricting contact with the outer hip folded posture that protrudes radially outward from the line segment P connecting S3.

  As shown in FIG. 10, the inversion prevention means F is formed on the shaft portion located between the mounting cylinder 37 and the lock nut 33 in the inner end side screw shaft portion 27 a of the second operation shaft 27. In addition, an elastically deformable rubber elastic correction cylinder 41 that comes into contact with the sides of the three upstream side locking links 28 in accordance with the extension operation to the reduced diameter posture is sheathed, and the downstream end of the mounting cylinder 37 The elastic correction cylinder 41 is in contact with the side of the three upstream locking links 28 that extend and swing radially inward while elastically compressing the elastic correction cylinder 41 locally. A correction collar 42 that is received in the outer-side folded posture at the set limit closest to the line segment P is integrally formed.

  The inversion preventing means F is provided after the elastic correction cylinder 24 and the elastic correction cylinder 24 are in contact with the upstream locking link 28 that is extended to the reduced diameter posture. And the correction collar portion 42 of the mounting cylinder 37, which is a hard restricting portion that abuts on the upstream side locking link 28.

Next, the operation means E will be described.
As shown in FIGS. 9 and 11, the first operating shaft 26 includes an attachment shaft portion 26 a fitted and fixed from the axial direction to the attachment cylinder portion 30 </ b> D of the first pressing plate 30 on the inner end side. A long operation main body cylinder shaft 26A and an operation extension cylinder shaft 26B fitted and fixed to the outer end side of the operation main body cylinder shaft 26A. The inner peripheral surface 26b of the operation extension cylinder shaft 26B is a regular hexagon. Are formed on the inner circumferential surface of different diameters.

  The second operation shaft 27 includes a long operation main body shaft 27A having an inner end side screw shaft portion 27a and an operation extension shaft 27B screwed and fixed to the outer end side of the operation main body shaft 27A. The operation extension shaft 27B has an outer end side screw shaft portion 27b into which an operation screw member 45 that can be brought into contact with the end portion of the operation extension cylinder shaft 26B of the first operation shaft 26 via a thrust bearing 44 is screwed. A large-diameter angular shaft portion 27c having a regular hexagonal outer peripheral surface that is slidably fitted only in the axial direction in a state in which the first operation shaft 26 is not rotatable relative to the operation extension cylinder shaft 26B is formed. Yes.

  Then, when the operation screw member 45 is screwed to the tightening side, the first operation shaft 26 is pushed and slid to the inner end side with respect to the second operation shaft 27 as shown in FIGS. The elastic annular body 34 that is in an uncompressed state is elastically expanded in a diameter-diameter state in close contact with the inner peripheral surface of the branch pipe portion 2 of the water pipe 1 by the clamping action accompanying the proximity movement of the first pressing plate 30 with respect to the two pressing plates 31. It deform | transforms and shields between the internal peripheral surface of the branch pipe part 2, and the outer peripheral part of both the press plates 30 and 31 in the sealing state.

  In addition, a pair of first presser operating rods 46 are detachably fitted and held on the operation extension cylinder shaft 26B of the first operating shaft 26, and both the first presser operating rods 46 include a second The second presser operation rod 47 that is detachably fitted to and held by the operation extension shaft 27B of the operation shaft 27 can be engaged and disengaged, and in the engaged state, the second operation on the first operation shaft 26 against the water pressure. The first locking ring 48 that prevents the shaft 27 from sliding to the outer end side and the pair of L-shaped locking pieces 49 fixed to the bottom wall portion 25B of the working case 25 can be freely engaged and disengaged. In the engaged state, the second locking ring 50 is provided that prevents the first operating shaft 26 from sliding to the outer end side with respect to the working case 25 against water pressure.

Next, using the drilling machine A and line closure device B configured as described above will be described replacement method of the butterfly valve V of the present invention using the valve body cutting method of the flow body piping system.

  (1) FIG. 1 shows an example of a pipe connection structure of a fluid piping system in which an air valve 3 is fixedly connected to a branch pipe portion 2 of a water pipe 1 via a connecting pipe 4 and a butterfly valve V. When it becomes necessary to replace the butterfly valve V due to a defect or the like, first, the connecting flange portion 3A of the air valve 3 is removed from the downstream connecting flange portion 10B of the butterfly valve V, as shown in FIG. Open / close working valve body 5 </ b> C provided in the downstream connecting flange portion 10 </ b> B with a valve body 5 </ b> C that can be slidably opened and closed along the direction perpendicular to the branch axis Y until the flow path in the valve box is fully opened or substantially fully opened. The upstream connection flange portion 5A of the valve 5 is fixedly connected in a sealed state via bolts 6 and nuts 7 so as to be detachable.

  (2) As shown in FIG. 3, the casing of the drilling machine A is provided with a hole saw 23 having a cut diameter larger than the outer diameter of the valve body 11 in the downstream connection flange portion 5 </ b> B of the work on-off valve 5. The 20 connecting flange portions 20A are fixedly connected in a sealed state via bolts 6 and nuts 7 so as to be detachable.

  (3) At this time, as shown in FIG. 4, when the valve body 11 of the butterfly valve V is in the valve closing operation position, communication is formed at the opposing portions of the valve box 10 and the boss portion 16 </ b> A of the valve operating tool 16. The lock pin 8B is inserted through the lock hole 8A of the first lock means 8 thus locked, so that the valve operating tool 16 and one valve shaft bolt 12A are locked at the valve closing operation position, and from the outer surface of the valve box 10 By driving the wedge member 9A of the second lock means 9 between the hexagonal head portion 12c of the other valve shaft bolt 12B protruding outward and the outer surface portion of the valve box 10 opposite to the hexagonal head portion 12c, the other valve shaft The bolt 12B is locked at the valve closing operation position.

  (4) As shown in FIGS. 5 to 7, while the hole saw 23 fixedly connected to the connecting flange portion 22 at the tip of the driving rotary shaft 21 of the drilling machine A is driven and rotated, First, a center drill 23B projecting from the tip turning locus of the cutting tip 23a of the cylindrical body 23A is drilled in the center position of the valve body 11 by the constituent members of the hole saw 23, and the cutting progresses. After the relative movement in the diametrical direction of both 23B and 11 is restricted, the cutting tip 23a of the cylindrical body 23A cuts the downstream opening of the partial spherical inner peripheral wall surface 10a of the valve box 10, and further, the hole saw 23 Of the valve shaft bolts 12A and 12B of the butterfly valve V is located on the radially outward side of the rotation trajectory of the taper pin 13, in detail, Cutting the shaft portion (stem portion) that is located radially outward than the periphery.

  At the time of this cutting, the valve operating tool 16 and one valve shaft bolt 12A are locked at the valve closing operation position by the lock pin 8B of the first lock means 8, and the other member is locked by the wedge member 9A of the second lock means 9. Since the valve shaft bolt 12B is locked at the valve closing operation position, when the valve shaft bolts 12A and 12B of the butterfly valve V are cut by the hole saw 23 of the drilling machine A, the valve shaft bolt 12A is at the valve opening operation position. The valve shaft bolts 12A and 12B should be securely and firmly maintained at the valve closing operation position even when the rotational force to the side and the rotational force to the slack side act on the other valve shaft bolt 12B. Therefore, cutting failure due to rotation of one valve shaft bolt 12A to the valve opening operation position side and rotational force to the slack side of the other valve shaft bolt 12B, recovery error of cut pieces, or hole saw 23 Biting It is possible to avoid the occurrence of a non-cleavable situation caused by the body.

  (5) As shown in FIG. 7, when the cutting process of both valve shaft bolts 12A, 12B of the butterfly valve V is completed, the valve body 11 cut by the retaining means outside the figure provided in the center drill 23B. And a part of both valve shaft bolts 12A and 12B are latched and held in the cylindrical body 23A, and in this state, the drive rotary shaft 21 of the drilling machine A is moved back and moved so that the hole saw 23 enters the storage space of the casing 20. After returning, the valve body 5C of the work on-off valve 5 is closed, and then the connecting flange part 20A of the drilling machine A is removed from the downstream side connection flange part 5B of the work on-off valve 5, and the cut off valve body 11 and the drilling machine A are removed.

  (6) As shown in FIGS. 9 to 11, the butterfly valve in which the valve body 11 and part of both the valve rods 12 </ b> A and 12 </ b> B are cut and removed by the hole saw 23 at the downstream connection flange portion 5 </ b> B of the work on-off valve 5. Pipe closing device B for closing the flow channel upstream of the installation location of the butterfly valve V in a sealed state by the operation in the state inserted into the branch pipe portion 2 of the water pipe 1 through the flow channel W in V. The connecting flange portion 25A of the casing 25 is fixedly connected in a sealed state through bolts 6 and nuts 7 so as to be detachable.

  At this time, with the pair of first locking rings 48 engaged with the second presser operating rod 47, the pair of second locking rings 50 are removed from both locking pieces 49 of the work case 25, and both operating shafts are removed. The closing means C and the retaining means D are stored in the storage chamber 25 </ b> C of the working case 25.

  Further, the positional relationship between the operation shafts 26 and 27 in the axial direction is regulated by the first locking rings 48, and in this state, the opposing distance between the pressing plates 30 and 31 compresses the elastic annular body 34. The elastic annular body 34 is maintained in a reduced diameter state because it is not or close to the interval.

(7) As shown in FIG. 12, the work on / off valve 5 is opened to push both the operation shafts 26 and 27 downward with respect to the work case 25 to move the pair of second locking rings 50. The two operating shafts 26 and 27 are pushed in and held in the operating position by engaging with both locking pieces 49 of the working case 25.
At this time, the retaining means D is located in the water pipe 1 having a larger cross-sectional area than the flow path in the branch pipe portion 2.

  (8) As shown in FIG. 13, when the pair of first locking rings 48 are removed from the second presser operating rod 47 and the second presser operating rod 47 is removed from the operation extension shaft 27B of the second operating shaft 27, The second operating shaft 27 slides to the outer end side with respect to the first operating shaft 26 by the water pressure of the tap water flowing through the water pipe 1 or this water pressure and the artificial pulling operating force, and in conjunction with this, A pair of locking links 28 and 29 that are pivotally connected across the first connecting piece 36 of the second pressing plate 31 and the second connecting piece 38 of the mounting cylinder 37 protrude while bending in a diameter-enlarging posture.

  In this state, as shown in FIG. 14, both the second locking rings 50 are removed from the both locking pieces 49 of the work case 25, and both the tap water pressure or the water pressure and an artificial pulling operation force are used. When the operating shafts 26 and 27 are slid upward with respect to the work case 25, the pair of locking links 28 and 29 that are bent in a diameter-enlarging posture causes the inner peripheral wall surface on the upstream side of the shielding portion by the elastic annular body 34. That is, it engages with the peripheral edge of the inner peripheral surface of the water pipe 1.

  Next, when the operating screw member 45 is artificially screwed to the tightening side, the first operating shaft 26 is pushed and slid to the inner end side with respect to the second operating shaft 27, and the first pressing plate 31 is moved in the first direction. The elastic annular body 34 in the reduced diameter state is elastically deformed into a diameter-expanded state in close contact with the inner peripheral wall surface of the branch pipe portion 2 due to the clamping action accompanying the proximity movement of the pressing plate 30, and the inside of the branch pipe portion 2 The space between the peripheral wall surface and the outer peripheral portions of the pressing plates 30 and 31 is shielded in a sealed state.

(9) As shown in FIG. 15, the drainage faucet outside the figure provided in the work case 25 is operated to discharge water, and after confirming that the water has stopped, the operation means E, The working case 25, the working on-off valve 5, the butterfly valve V, and the connecting pipe 4 are removed in order.
(9) As shown in FIG. 16, the upstream connection flange 52A of the new on-off valve 52 is fixed to the connection flange 2A of the branch pipe 2 through a bolt 6 and a nut 7 so as to be detachable in a sealed state. The connecting flange portion 51A of the second work case 51 capable of accommodating the closing means C and the retaining means D of the pipe closing device B is connected to the downstream side connecting flange portion 52B of the new on-off valve 52 with the bolt 6 -It is fixedly connected in a sealed state through the nut 7 so as to be detachable, the pipe closing device B is raised and the closing means C and the retaining means D are stored in the second work case 51, and then newly The second opening / closing valve 52 is closed to remove the second working case 51 from the new opening / closing valve 52 and remove the pipe closing device B together.

  (10) As shown in FIG. 17, the connection flange portion 3A of the air valve 3 is fixedly connected to the downstream connection flange portion 52B of the new on-off valve 52 in a sealed state through bolts 6 and nuts 7 so as to be detachable. To do.

[Other Embodiments]
(1) In the above-described first embodiment, the fluid piping system in which the branch pipe portion 2 is integrally formed in the middle of the fluid pipe 1 such as a water pipe has been described, but the fluid pipe 1 is provided along the circumferential direction thereof. And a branch pipe portion 2 that protrudes from the pipe radial direction with respect to a through-hole formed in the fluid pipe 1 in one split joint body. The technique of the present invention may be applied to a fluid piping system in which a certain pipe joint is mounted and a butterfly valve is attached to a branch pipe portion of the pipe joint.

  (2) In the first embodiment described above, the work on / off valve 5 and the butterfly valve V are removed and a new on / off valve 52 is attached, but after the butterfly valve V is removed, the work on / off valve 5 is newly opened and closed. You may use as it is as a valve.

(3) In the first embodiment described above, the method of cutting and removing the valve body 11 of the butterfly valve V connected to the branch pipe portion 2 side of the water pipe 1 with the hole saw 23 has been described. You may apply the technique of this invention to the construction method which cuts and removes the valve body 11 of the butterfly valve V connected to the part with the hole saw 23. FIG.
Also in this embodiment, the work on / off valve 5 having a valve element that can fully open or substantially fully open the flow path is connected to the downstream opening of the butterfly valve V, and the work on / off valve 5 is perforated. Used as a new on-off valve after work.

  (4) In the first embodiment described above, the cutting diameter of the hole saw 23 is set to an outer diameter that is slightly larger than the outer diameter of the valve body 11, and the outer peripheral edge of the valve body 11 out of both valve rods. Although the valve stem portion located radially outward is cut by the hole saw 23, the cutting diameter of the hole saw 23 is larger than the maximum diameter of the rotation trajectory of the connecting member 13, and the valve body 11 The outer diameter may be substantially the same as or smaller than the outer diameter.

  (5) In the first embodiment described above, the locking link 28 that protrudes from the pipe closing device B while bending in a diameter-enlarging posture that can be engaged with the peripheral edge of the branch port on the inner peripheral surface of the water pipe 1. , 29 provided with retaining means D, but does not include such retaining means D, that is, blocks (blocks) the flow path in the branch pipe portion 2 of the water pipe 1. ) May be carried out using the pipe closing device B that uses only the retaining function of the closing means C.

Front view of the butterfly valve replacement method using the valve body cutting method of the fluid piping system of the present invention Longitudinal front view with air valve removed Front view partially cut away when the cutting machine is installed Enlarged longitudinal front view of the main part when locked by the first and second locking means Front view of an enlarged part of the main part when the center drill of the cutting machine is fed to the valve body Enlarged longitudinal front view of main part when cutting tip of cylindrical body of cutting machine cuts downstream opening of partial spherical inner peripheral wall surface of valve box Enlarged longitudinal front view of the main part when both valve shaft bolts of the butterfly valve are cut with the cutting tip of the cylindrical body of the cutting machine Front view of the enlarged part of the main part when the cutting machine is removed Longitudinal front view with pipe line closure device installed Enlarged sectional front view of the closing means and retaining means of the pipe closing device Enlarged sectional front view of the operation means of the pipeline blockage device Cross-sectional front view when closing means and retaining means are lowered into the water pipe Cross-sectional front view when the locking link pair of the retaining means is expanded in diameter Enlarged front view of the main part when engaging a pair of locking links in the expanded diameter posture and elastically deforming the elastic annular body in the expanded diameter state Cross-sectional front view when the operating means, working case, working on-off valve, butterfly valve, connecting pipe are removed Cross-sectional front view when a new on-off valve and second work case are assembled Front view when an air valve is attached to a new on-off valve

Explanation of symbols

A Drilling machine B Pipe closing device V Butterfly valve X Pipe axis Y Branch axis Z Opening / closing rotation axis 1 Fluid pipe (water pipe)
2 branch pipe portion 5 work on-off valve 8 first lock means 8A lock hole 8B lock pin 9 second lock means 9A wedge member 10 valve box 10a partial spherical inner peripheral wall surface 11 valve element 12A valve stem (valve shaft bolt)
12B Valve stem (Valve shaft bolt)
13 Connecting member (taper pin)
16 Valve operation tool 16A Boss part 23 Hole saw 52 On-off valve

Claims (6)

  A working on / off valve is connected to the downstream opening of the valve box of the butterfly valve connected to the fluid pipe, and the butterfly valve disc and both valve stems are fixed to the downstream opening of the working on / off valve. A drilling machine equipped with a hole saw configured with a cutting diameter larger than the maximum diameter of the rotation trajectory of the connecting member to be connected is attached to the inside of the fluid pipe by the hole saw of the drilling machine inserted from the downstream opening of the work on-off valve. While maintaining the fluid flow of the butterfly valve, remove the valve stem part that is located outside the pivot trajectory of the connecting member with the hole saw and remove it along with the valve body. With the pipe closing device inserted upstream through the flow path in the butterfly valve, the upstream flow path from the place where the butterfly valve is installed is closed in a sealed state, and the butterfly valve and the work on / off valve are removed. Replace with another on-off valve Both valve replacement method of the fluid piping system, characterized by removing the pipe closure apparatus from the downstream side opening of the closing valve.   In a fluid piping system in which a butterfly valve is attached to the branch pipe section on the fluid pipe side, a working on-off valve is connected to the downstream opening of the valve box of the butterfly valve, and the downstream opening of the working on-off valve is connected to the downstream opening. A drilling machine equipped with a hole saw having a cutting diameter larger than the maximum diameter of the turning trajectory of the connecting member for fixedly connecting the valve body of the butterfly valve and both valve stems is mounted downstream of the work on-off valve With the hole saw of the drilling machine inserted from the side opening, the valve stem portion located radially outward from the pivotal trajectory of the connecting member of both valve stems of the butterfly valve while maintaining the fluid flow in the fluid pipe. After cutting with a hole saw and removing it together with the valve body, the upstream side of the butterfly valve installation location is sealed by the pipe closing device inserted upstream through the flow path inside the butterfly valve that has been cut and removed Blocked with butterfly While it replaced with another opening and closing valve by removing the line valve and the working-off valve, the valve replacement method of the fluid piping system, characterized by removing the pipe closure apparatus from the downstream side opening of the closing valve. The hole diameter of the hole saw is set to an outer diameter that is substantially the same as or larger than the outer diameter of the valve body, and the valve stem portion located radially outward from the valve body is the hole saw of both valve stems. The valve replacement method for a fluid piping system according to claim 1 or 2 , wherein the valve replacement method is configured to cut at a point. Before cutting with the hole saw, the first lock means for locking one valve rod of the butterfly valve or the valve operating tool connected thereto in the valve closing operation position is operated in the locked state, and the other valve rod of the butterfly valve The valve replacement method for a fluid piping system according to any one of claims 1 to 3, wherein the second locking means for locking the valve at a valve closing operation position is operated in a locked state. The inner circumferential wall surface portion on the downstream opening side that is smaller than the outer diameter of the valve body is cut and removed from the inner circumferential wall surface of the valve box of the butterfly valve at the time of cutting with the hole saw. Item 5. A valve replacement method for a fluid piping system according to any one of Items 1 to 4 . When the valve body is in the valve closing operation position, the first locking means spans a lock hole formed in communication with a portion facing the valve box and the boss portion of the valve operating tool connected to one valve rod. The second locking means includes an end of another valve stem protruding outward from the outer surface of the valve box and an outer surface of the valve box opposite to the end of the valve box. The valve replacement method for a fluid piping system according to claim 4 , wherein the valve is constructed so as to be locked by driving a wedge member between the portions.

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