JP4313621B2 - Piping structure, existing pipe cutting method, continuous flow valve insertion method, gate valve body and continuous flow insertion valve device - Google Patents

Description

[0001]
[Background of the invention]
Field of Invention:
The present invention relates to a piping structure, an existing pipe cutting method, an uninterrupted flow valve insertion method, a gate valve body and an uninterrupted flow insertion valve device used in the method.
[0002]
Description of conventional technology:
Conventionally, a continuous water valve insertion method is known in which an existing pipe is perforated with unrestricted water and a valve is inserted into a perforated portion of the existing pipe in a pipe line including the existing pipe.
[0003]
28 (a) and 28 (b) show an outline of a conventional continuous water valve insertion method disclosed in U.S.P.No. 3,948,282.
In the prior art shown in this figure, the existing pipe 1 of FIG. Next, a work gate valve 801 and the like are attached to the sealed case 800. Thereafter, a circular hole 803 is drilled in the existing pipe 1 with a hole saw 802 in accordance with a well-known method. After this drilling, as shown in FIG. 28 (b), a valve body 804 that fits into the drilled circular hole 803 is inserted.
[0004]
In this conventional valve insertion method, since the hole 803 having a diameter substantially equal to the inner diameter of the existing pipe 1 is provided, the hermetic case 800 of FIG.
Moreover, in this prior art, since the water pressure is applied to the valve body 804 in FIG. 28B for a large area corresponding to the circular hole, the diameter of the valve rod 806 is increased.
Moreover, in this valve insertion method, the peripheral portion 805 of the hole 803 in the existing pipe 1 becomes thin, and pressure from the valve body 804 is applied to the peripheral portion 805, so that the existing pipe 1 is easily damaged.
[0005]
SUMMARY OF THE INVENTION
The present invention has been made to solve the above-mentioned conventional problems, and its main purpose is to provide a piping structure, an existing pipe cutting method, and an uninterrupted flow valve insertion method capable of reducing the size of the sealed case.
Another object of the present invention is to provide a piping structure, an existing pipe cutting method, and an uninterrupted flow valve insertion method in which an existing pipe is not easily damaged.
Still another object of the present invention is to provide a gate valve body or the like inserted by such a construction method.
[0006]
In order to achieve the above object, the piping structure of the present invention includes an existing pipe, a sealed case, and a gate valve body.
The existing pipe has a groove-shaped cutting groove that is cut out in a range of about 180 ° in the circumferential direction of the existing pipe.
The sealed case is divided into a plurality of circumferential directions of the existing pipe and surrounds the existing pipe in an airtight state.
In the closed state, the gate valve body has a rubber packing that contacts an inner peripheral surface of the existing pipe and a cutting surface that forms the cutting groove in the existing pipe. The gate valve body moves in the radial direction of the existing pipe in the sealed case and enters the existing pipe from the cutting groove, whereby the rubber packing stops the flow of fluid in the existing pipe.
[0007]
In a preferred embodiment of the present invention, the groove-shaped cutting groove is formed by cutting an existing pipe with a cutting tool.
Further, in a preferred embodiment of the present invention, the angle formed by the cutting surfaces at both ends in the circumferential direction in the cutting groove and the surface of the existing pipe in the portion is set to an angle larger than 45 °, More preferably, it is set in the range of 45 ° to 90 °.
In a further preferred embodiment of the present invention, both end portions in the circumferential direction of the cutting groove are formed in a substantially U shape.
[0008]
The piping structure of the present invention is completed by, for example, cutting an existing pipe by the existing pipe cutting method of the present invention and then inserting the valve into the pipe line by the uninterrupted flow valve insertion method of the present invention.
[0009]
That is, in the existing pipe cutting method of the present invention, first, a part of the existing pipe is surrounded in an airtight state by a sealing case divided into a plurality of parts in the circumferential direction of the existing pipe, and in the radial direction of the existing pipe. A cutting tool that is rotatably supported around a set axis and has a plurality of cutting blades on the tip end surface and outer peripheral surface of the column is accommodated in the sealed case in a state of being attached to the sealed case. Next, the cutting tool is rotated in the radial direction of the existing pipe while the cutting tool is rotated around the axis by the power of a prime mover and the cutting pipe is cut by the rotation of the cutting tool. And at the same time rotating the cutting tool in the circumferential direction by rotating at least a part of the sealed case in the circumferential direction of the existing pipe, thereby causing the cutting tool to perform a feeding motion. Is cut by the cutting tool over a range of about 180 ° in the circumferential direction.
[0010]
In accordance with the cutting method of the present invention, the existing pipe is cut over a range of about 180 ° by the cutting tool, and then the valve is inserted into the pipe line. The gate valve body of this valve enters the existing pipe from the cut groove and closes the cut groove and closes the existing pipe by pressing against the inner peripheral surface of the existing pipe.
[0011]
In the present invention, the “existing pipe” refers to a pipe in which a fluid such as water flows in the pipe, and is generally buried in the ground.
“Sealing” does not mean completely sealing, but means keeping water (air) tight enough to allow construction with constant water (flow). Therefore, the “sealed case” refers to a case having a pressure resistance capable of withstanding the pressure of the fluid flowing in the existing pipe and a certain level of water stopping performance.
Further, “enclose in an airtight state” means to seal to an extent that does not hinder cutting and valve insertion after cutting. For example, a drain outlet is provided in the sealing case, The drain outlet may be opened during cutting, and the chips may be discharged together with water from the drain outlet.
[0012]
Since the “cutting tool” used in this cutting method has a plurality of cutting edges, the cutting tool does not include a cutting tool or a cutter wheel having a single continuous cutting edge. .
Here, in this specification, “columnar” means that a truncated cone, a shape obtained by adding a cone to a cylinder, and a conical shape are included in addition to a cylinder. Moreover, the column shape may be shorter than the outer diameter of the cutting tool.
When cutting an existing pipe with mortar lining on the inner surface of the pipe, a cutting tool provided with many cutting edges (tips) made of cemented carbide or a cutting tool using diamond particles as cutting edges It is preferable to use it.
[0013]
In the present invention, “cutting” means that a plurality of cutting blades are rotated to cut off a part of the tube wall. The “cutting motion” refers to rotating a plurality of cutting blades, while the “feeding motion” refers to a position at which new portions of the tube wall can be cut one after another by the cutting tool. This refers to moving the cutting tool.
In the present invention, “the cutting tool is sent in the radial direction of the existing pipe and the sealing case is rotated in the circumferential direction” means that the sealing case is rotated after the cutting tool is sent in the radial direction of the existing pipe. In addition, the case where the sealing case is rotated while feeding the cutting tool in the radial direction of the existing pipe is included.
[0014]
In the present invention, “inserting a valve (into a pipe line)” does not mean physically inserting a valve or a gate valve body into a cut-off portion of an existing pipe, but an existing pipe line. This means installing a valve to control the water stoppage or flow rate of the pipe.
Further, in this cutting method, “cutting in the circumferential direction over a range of about 180 °” means that the existing pipe over a range in which the gate valve body having a size approximate to the inner diameter of the existing pipe can be inserted from the cutting groove. Is generally set to a value smaller than 180 ° of about 150 ° to 170 °.
[0015]
On the other hand, the gate valve body of the present invention enters the existing pipe from the opening formed in the existing pipe, and the first rubber packing portion of the gate valve body contacts the cutting surface forming the hole of the existing pipe. In addition, the second rubber packing portion is a gate valve body that comes into contact with the inner peripheral surface of the existing pipe and is in a valve-closing state, and the cutting tool having a cutting edge along the tip surface and the cylindrical surface is used to A pipe is cut in the pipe radial direction, and then the cutting tool is moved along the circumferential direction of the pipe to form a cutting surface in the groove-shaped opening formed over the range of about 180 ° in the circumferential direction of the existing pipe. The first rubber packing portion has a corresponding contact surface.
[0016]
Further, the continuous flow insertion valve device (gate valve) according to the present invention is divided into a plurality in the circumferential direction of the existing pipe, surrounds a part of the existing pipe in an airtight state, and the airtight state. And a sealing case rotatable around the existing pipe, and the gate valve body accommodated in the sealing case.
In the above-mentioned piping structure and construction method, it is difficult to perceive the apparatus for carrying out the piping structure and construction method as a direct infringement, so that the scope of rights can be easily defined before construction. Claims are also made for the gate valve body and the valve device for continuous flow insertion.
[0017]
[Explanation of Examples]
The invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings, in which: However, the examples and drawings are for illustration and description only, and the scope of the present invention is defined by the claims. In the accompanying drawings, the same part numbers in a plurality of drawings indicate the same or corresponding parts.
[0018]
First embodiment
1 to 12 show a first embodiment.
Hereinafter, the existing pipe cutting method and the continuous water valve insertion method of the first embodiment will be described in the order of steps.
[0019]
Cutting device (cutting device)
As shown in FIG. 2, in this embodiment, a central first sealed case 2A and a pair of left and right second sealed cases 2B are used. As shown in FIG. 1, the first sealed case 2A includes first and second divided cases 221 and 222 that are divided into two in the circumferential direction, and a guiding bush 222a. The second sealed case 2B (FIG. 2) is also divided into two in the circumferential direction. As shown in FIG. 3A, a space between these cases 221 (FIG. 2), 222, 2A, 2B and between the second sealed case 2B and the existing pipe 1 is sealed with a rubber ring 224 or the like. ing.
[0020]
The second split case 222 has a branch portion 222b protruding in a branch shape outward in the radial direction C of the existing pipe 1, and a main bearing is provided on the branch portion 222b via the guide bush 222a. 232 is attached in the radial direction C of the existing pipe 1 so as to be slidable and movable back and forth. A rubber ring 224 is sealed between the guide bush 222a, the branched portion 222b, and the main bearing 232. An opening 222 c into which the columnar cutting tool 230 enters is formed in the branched portion 222 b in the second divided case 222.
[0021]
The cutting machine 3 is attached to the guide bush 222a fixed to the first sealed case 2A via a main bearing 232. That is, a first motor (an example of a prime mover) 231 for rotating the tool is fixed above the main bearing 232. On the other hand, the cutting tool 230 is disposed inside the main bearing 232. The cutting tool 230 is integrally formed with a main shaft (cutter shaft) 233 that is rotatably supported by the main bearing 232. The first motor 231 rotates the cutting tool 230 via a coupling 234 fixed to the output shaft 231a and the main shaft 233 of the first motor 231.
[0022]
As shown in FIG. 3B, the cutting tool 230 has a plurality of cutting blades 230f on the substantially cylindrical tip surface 230d and outer peripheral surface 230e, respectively. The main shaft 233 is integrally formed with the cutting tool 230. As shown in FIG. 1, the cutting tool 230 and the axis 233 a of the main shaft 233 are set in the radial direction C of the existing pipe 1. The cutting tool 230 performs a cutting motion by rotating around the axis 233 a set in the radial direction C of the existing pipe 1.
[0023]
A cutting feed frame 236 is fixed to the branched portion 222b of FIG. The cutting feed frame 236 includes a long bolt 236a fixed to the branch portion 222b and a top plate 236b fixed to the upper end of the long bolt 236a. A male screw 237 for cutting feed is screwed into a bush 236c provided on the top plate 236b of the cutting feed frame 236.
[0024]
The main bearing 232 advances in the cutting direction C by rotating the male screw for cutting 237 and screwing it in the cutting direction C. Therefore, by rotating the cutting tool 230 and sending the cutting tool 230 together with the main bearing 232 in the cutting direction C and causing the cutting tool 230 to enter the opening 222c, as shown in FIG. The existing pipe 1 can be cut. The guide bush 222a is fixed to the cutting feed frame 236 via the connection fitting 238 shown in FIG. 1, and is collected together with the cutting feed frame 236 after the completion of cutting.
[0025]
In the present embodiment, the case rotating device 4 of FIG. 2 that rotates the first sealed case 2A around the existing pipe 1 is provided. The case rotating device 4 has a pair of second motors 242 for rotating the case. The second motor 242 rotates the drive gear 244 for rotating the case via the output shaft 247. The drive gear 244 rotates a case rotating driven gear 245 fixed to the first sealed case 2A. Accordingly, by rotating the first sealed case 2A around the existing pipe 1 by about 180 ° while rotating the cutting tool 230 in the incision state of FIG. 4, the existing pipe 1 is cut to cut the cutting groove of FIG. 12C can be formed.
[0026]
As shown in FIG. 3, the second sealed case 2B constitutes a misalignment prevention tool 5A. The second sealed case 2B is divided into two in the circumferential direction R (FIG. 1) of the existing pipe 1. In the second sealed case 2B, a number of set screws 251 are provided in the circumferential direction R (FIG. 1) at two locations separated in the tube axis direction S, respectively. The first sealed case 2A and the second sealed case 2B have a rotation guide portion 250 that slides in the tube axis direction S and the radial direction via the liner 252. The pair of second sealed cases 2 </ b> B are fixed to the existing pipe 1 by set screws 251. The second sealed case 2B guides the first sealed case 2A and prevents the first sealed case 2A from shifting or shaking in the tube axis direction S of the existing tube 1. Accordingly, the first sealed case 2 </ b> A rotates smoothly when rotating around the existing pipe 1. A ball bearing or the like may be used instead of the liner 252.
[0027]
Cutting process
Next, the cutting procedure will be described.
First, with the fluid (water) flowing in the existing pipe 1 in FIG. 2, the operator attaches the first and second sealed cases 2A and 2B to the existing pipe 1 and uses the assembly bolts 228 in FIG. The divided cases 221 and 222 are assembled. Thus, as shown in FIG. 2, the first and second sealed cases 2A and 2B surround the existing pipe 1 in an airtight state. The cutting machine 3 is attached in advance to the guiding bush 222a of the first sealed case 2A.
[0028]
Next, as shown in FIGS. 5A to 5B, a cutting position by the cutting tool 230 is set. That is, the case rotating device 4 of FIG. 2 is driven to rotate the first sealed case 2A and the cutting machine 3 to a position where the axis 233a of the cutting tool 230 is substantially horizontal.
[0029]
Next, when the operator drives the first motor 231 in FIG. 1, the first motor 231 rotates the cutting tool 230 around the axis 233 a of the main shaft 233, and the existing pipe 1 is rotated by the rotation of the cutting tool 230. A cutting motion for cutting is performed. When the operator screws in the cutting feed male screw 237 in the cutting direction C while the cutting motion is being performed, the cutting tool eventually appears as shown by a two-dot chain line in FIG. The tip end surface 230d of 230 advances to a position that penetrates a part of the tube wall 1a of the existing tube 1. Thus, the cutting with the cutting tool 230 is completed.
[0030]
After the cutting, when the operator drives the second motor 242 for rotating the case shown in FIG. 2, the first sealed case 2A is guided to the second sealed case 2B via the pair of drive gears 244 and the driven gear 245. Rotate around the existing pipe 1 in the state of being made. Thereby, the cutting tool 230 rotates around the main shaft 233 while rotating about 180 ° (for example, 160 °) along the outer periphery of the existing pipe 1 together with the first sealed case 2A, and cuts the existing pipe 1 into a semi-annular shape. Then, the cutting groove 12 </ b> C is formed in the existing pipe 1.
That is, the second motor 242 (FIG. 1) rotates the cutting tool 230 in the circumferential direction R by rotating the first sealed case 2A in the circumferential direction R (FIG. 1) of the existing pipe 1. As shown in FIGS. 5B to 5C, the cutting tool 230 is fed. Thereby, the cutting tool 230 cuts the existing pipe 1 into a semi-annular shape, and forms a cutting groove 12 </ b> C in the existing pipe 1. After the cutting is completed, the cutting tool 230 is returned to the original position as indicated by a two-dot chain line. Thereafter, the operator removes the case rotating device 4 of FIG.
Note that a drainage valve may be attached to the main bearing 232, and chips from the drainage valve may be discharged.
[0031]
Cutting machine removal process
Next, the operator removes the cutting machine 3 by the method described below. That is, as shown in FIG. 6, the work gate valve 273 is joined to the branch portion 222b, and the work upper tank 274 is overlapped and joined to the work gate valve 273. At the time of this joining, the worker joins the cutting feed frame 236 to the tip of the elevating shaft 276 that penetrates the working upper tank 274. After this joining, the operator removes the nut 239. After the removal, the operator pulls up the lifting shaft 276 of FIG. 7 and takes out the cutting machine 3 from the first sealed case 2A into the working upper tank 274. After this removal, the operator closes the work gate valve 273. After the valve closing, the operator separates the work upper tank 274 from the work gate valve 273.
[0032]
Next, the structure of the gate valve body of the valve inserted into the pipe line will be described.
The valve includes a gate valve body 8a shown in FIG. A rubber packing 8d is attached to the gate valve body 8a. When the gate valve 8a enters the existing pipe 1 from the cutting groove 12C, the rubber packing 8d closes the cutting groove 12C and presses against the inner surface 1b of the existing pipe 1. That is, the rubber packing 8d is pressed against the first rubber packing portion 8d1 pressed against the cutting surface 12f of the cutting groove 12C and the inner peripheral surface 1b of the existing pipe 1 as shown in FIGS. 9 (c) and 9 (d). The second rubber packing portion 8d2 is formed continuously. The gate valve 8a has first and second mounting grooves 8a1, 8a1 and 8d2 for mounting the first and second rubber packing portions 8d1 and 8d2 shown in FIGS. 9A and 9B. 8a2 is formed.
[0033]
Valve insertion process
Next, the worker houses the valve lid 8b and the gate valve body 8a of FIG. 10 in the work upper tank 274, and joins the work upper tank 274 to the work gate valve 273. The gate valve 8A includes a spindle 8c that opens and closes the gate valve body 8a. In the gate valve 8A, when the spindle 8c is rotated, the gate valve body 8a of FIG. 8 enters the existing pipe 1 from the cutting groove 12C, and the rubber packing 8d provided on the gate valve body 8a is a cutting surface of the existing pipe 1. 12f and the valve which press-contacts to the internal peripheral surface 1b of the existing pipe 1 are comprised. That is, the existing pipe 1 constitutes a part of the valve box of the gate valve 8A.
[0034]
After the work upper tank 274 shown in FIG. 10 is attached, the worker opens the work gate valve 273 as shown in FIG. 11 and lowers the lifting shaft 276. As a result, the valve lid 8b comes into contact with the branched portion 222b. After this contact, the operator joins the valve lid 8b and the branched portion 222b with the flange bolt 8e. After this joining, the operator removes the work upper tank 274 and the work gate valve 273. Thereafter, the operator pushes the rubber ring 264 into the packing insertion portion 260 of the second sealed case 2B of FIG. 12 and attaches the split ring 265 to the second sealed case 2B. Thus, the gate valve 8A is arranged at a position corresponding to the cutting groove 12C, and the gate valve 8A is inserted into the pipe line 1A.
[0035]
Here, in the first embodiment, the rubber packing 8d is pressed against the cutting surface 12f of FIG. 8 and the inner peripheral surface 1b of the existing pipe 1, that is, since the existing pipe 1 is used as a valve box, the existing pipe 1 A big external force will be added to. However, in this embodiment, the width of the cutting groove 12C formed in the existing pipe 1 is small, and in particular, since a thin portion does not occur in the existing pipe 1, when the pipe line 1A is closed by the gate valve body 8a, There is no possibility that the existing pipe 1 is damaged.
Further, when the gate valve body 8a is closed, the gate valve body 8a is supported by the cutting surface 12f via the first rubber packing portion 8a1 in the tube axis direction S, so that even when the pressure at the time of water stoppage is received. The valve body 8a is not easily distorted. Further, since the width of the cutting groove 12C is small, the force for pushing the valve body 8a upward by water pressure is also small. Therefore, the spindle 8c can be made thin.
[0036]
In the first embodiment, the sealed case is divided into the first sealed case 2A and the second sealed case 2B, and a part of the sealed case, that is, the first sealed case 2A is rotated. The first sealed case 2A and the second sealed case 2B may be integrally formed. In this case, a misalignment prevention tool is separately provided beside the sealed case, and the entire sealed case is rotated. An example of this is shown in the following second embodiment.
[0037]
Second embodiment
13 to 24 show a second embodiment.
Hereinafter, in the second embodiment, after describing the sealed case, the piping structure will be described.
[0038]
Sealed case
As shown in FIG. 13A, the sealed case 2 is divided into first and second divided cases 211 and 212, and the divided surface 215 is sealed by the rubber packing 214 of FIG. 13B. Note that the split surfaces 215 of the two split cases 211 and 212 are configured to be metal touched with each other. Further, packing insertion portions 260 into which the rubber rings 264 of FIG. 15 are pushed are provided at both ends of the sealed case 2.
[0039]
As shown in FIG. 14B, a bolt insertion hole 217 for fixing the valve lid and a bolt insertion hole 218 for fixing the work gate valve are formed in the flange 216 of the second divided case 212 in FIG. Has been. Reference numeral 219 denotes a hole for inserting an assembly bolt.
[0040]
Piping structure
15 to 18 show the piping structure.
In FIG. 15, a cutting groove 12 </ b> C is formed in the existing pipe 1. As shown in FIG. 16, the cutting groove 12 </ b> C is cut out over a range of about 180 ° in the circumferential direction of the existing pipe 1. The cutting groove 12C is formed by cutting the existing pipe 1 with a cutting tool described later. As shown in FIG. 15, the cutting groove 12C has both end portions 12c1 in the circumferential direction formed in a substantially U shape. Thus, since both ends 12c1 of the cutting groove 12C draw a smooth curve, the both ends 12c1 can be easily sealed.
In addition, the part except the said both ends 12c1 in the said cutting groove 12C is formed in the width | variety of a fixed groove | channel.
[0041]
Further, the cutting surface 12f forming the cutting groove 12C is set to have an angle of 45 ° to 90 ° with respect to the surface 1c of the existing pipe 1 in the portion. That is, as shown in FIG. 16, the existing pipe 1 does not have a thin part in the peripheral part of the cutting groove 12C. Therefore, as shown in FIGS. 17 and 18, even if the rubber packing 8d of the valve body 8a is pressed against the cutting surface 12f, there is no possibility that the existing pipe 1 is damaged. Therefore, the gate valve 8A can be opened and closed many times.
[0042]
The sealed case 2 is divided into two in the circumferential direction R of the existing pipe 1 and is sealed with a rubber packing 214 to surround the existing pipe 1 in an airtight state. The first divided case 211 is formed along the outer peripheral surface of the existing pipe 1. On the other hand, the second split case 212 has a movement hole 212d through which the gate valve body 8a moves in the radial direction C of the existing pipe 1. A valve lid 8b is fixed to the second divided case 212. The valve lid 8b closes the movement hole 212d of the second divided case 212. The valve lid 8b and the second divided case 212 form a space for accommodating the gate valve body 8a when the valve is opened in FIG.
[0043]
As shown in FIG. 17, the gate valve body 8a has a rubber packing 8d. The rubber packing 8d includes a first rubber packing 8d1 that contacts a cutting surface 12f (shown by a broken line in FIG. 18) that forms a cutting groove, and a second rubber packing 8d2 that contacts an inner peripheral surface 1b of the existing pipe 1. It is formed integrally. The rubber packing 8d is molded by being integrally baked on the gate valve body 8a.
[0044]
When the spindle (valve rod) 8c is rotated, the gate valve body 8a moves in the radial direction C of the existing pipe 1 in the sealed case 2 as shown in FIGS. When the gate valve 8a enters the existing pipe 1 from the cutting groove 12C, the rubber packing 8d comes into contact with the cutting surface 12f and the inner peripheral surface 1b of the existing pipe 1, and the fluid in the existing pipe 1 flows. Stop the flow. In addition, the internal peripheral surface 1b of the existing pipe 1 of a present Example is formed by the mortar lining.
[0045]
Cutting device (cutting device)
As shown in FIG. 19, the sealing case 2 includes first and second divided cases 211 and 212 that are divided into two in the circumferential direction, and a guiding bush 212a.
[0046]
The second split case 212 has a branch portion 212b protruding in a branch shape outward in the radial direction C of the existing pipe 1, and a main bearing is provided on the branch portion 212b via the guide bush 212a. 232 is attached in the radial direction C of the existing pipe 1 so as to be slidable and movable back and forth. As shown in FIG. 21A, a rubber ring 214 seals between the guiding bush 212a, the branched portion 212b, and the main bearing 232. An opening 212c into which the columnar cutting tool 230 enters is formed in the branched portion 212b in the second divided case 212.
[0047]
A cutting machine 3 is attached to the guide bush 212 a fixed to the hermetic case 2 via a main bearing 232. That is, a tool rotating motor (an example of a prime mover) 231 is fixed above the main bearing 232. On the other hand, the cutting tool 230 is disposed inside the main bearing 232. The cutting tool 230 is integrally formed with a main shaft (cutter shaft) 233 that is rotatably supported by the main bearing 232. The motor 231 rotates the cutting tool 230 via a coupling 234 fixed to the output shaft 231a and the main shaft 233 of the motor 231.
[0048]
As shown in FIG. 21B, the cutting tool 230 has a plurality of cutting blades 230f on a substantially cylindrical tip surface 230d and an outer peripheral surface 230e, respectively. The main shaft 233 is integrally formed with the cutting tool 230.
Further, in this embodiment, a tapered portion 230t is provided in the cutting tool of FIG. 21B in order to make the cutting surface 12f tapered as shown in FIG. Further, in order to prevent the tapered portion 230t from entering too much toward the center of the existing pipe 1, a cutting stopper 230s is fixed to the cutting tool 230.
The cutting stopper 230s is made of a hard resin, and it is preferable that a groove for releasing chips is formed in the cutting stopper 230s. In this embodiment, the notch stopper may be provided on the guide bush 212a without being provided on the cutting tool 230.
As shown in FIG. 19, the cutting tool 230 and the axis 233 a of the main shaft 233 are set in the radial direction C of the existing pipe 1. The cutting tool 230 performs a cutting motion by rotating around the axis 233 a set in the radial direction C of the existing pipe 1.
[0049]
A cutting feed frame 236 is fixed to the branched portion 212b of FIG. The cutting feed frame 236 includes a long bolt 236a fixed to the branch portion 212b and a top plate 236b fixed to the upper end of the long bolt 236a. A male screw 237 for cutting feed is screwed into a bush 236c provided on the top plate 236b of the cutting feed frame 236.
[0050]
The main bearing 232 advances in the cutting direction C by rotating the male screw for cutting 237 and screwing it in the cutting direction C. Therefore, by rotating the cutting tool 230 and sending the cutting tool 230 together with the main bearing 232 in the cutting direction C and causing the cutting tool 230 to enter the opening 212c, as shown in FIG. The existing pipe 1 can be cut. The guide bush 212a is fixed to the cutting feed frame 236 via the connecting fitting 238 shown in FIG. 19, and is collected together with the cutting feed frame 236 after the completion of cutting.
[0051]
As shown in FIG. 20, shift prevention tools 5 are provided on both sides of the sealed case 2. The displacement prevention tool 5 is fixed to the existing pipe 1 with a number of set screws 251, and is in contact with both sides of the sealed case 2 via the liner 252. Accordingly, the slip prevention tool 5 guides the sealed case 2 to prevent the sealed case 2 from being displaced or shaken in the tube axis direction S of the existing pipe 1. Accordingly, the sealed case 2 rotates smoothly when rotating around the existing pipe 1. Reference numeral 253 denotes a pressing screw that presses the liner 252 against the sealing case 212.
[0052]
Cutting process
Next, the cutting procedure will be described.
First, with the fluid (water) flowing in the existing pipe 1 in FIG. 20, the operator attaches the sealed case 2 to the existing pipe 1 and assembles both split cases 211 and 212 with assembly bolts (not shown). Thus, as shown in FIG. 20, the sealed case 2 surrounds the existing pipe 1 in an airtight state. The cutting machine 3 is attached in advance to the guiding bush 212a of the sealed case 2.
[0053]
Next, as shown in FIGS. 23A to 23B, the cutting position by the cutting tool 230 is set. That is, the operator rotates the sealing case 2 and the cutting machine 3 to a position where the axis 233a of the cutting tool 230 becomes substantially horizontal by human power or a winch.
[0054]
Next, when the operator drives the motor 231 shown in FIG. 19, the motor 231 rotates the cutting tool 230 around the axis 233 a of the main shaft 233 and cuts the existing pipe 1 by the rotation of the cutting tool 230. Have exercise. When the operator screws in the cutting feed male screw 237 in the cutting direction C in a state where the cutting motion is performed, the cutting tool is eventually shown as indicated by a two-dot chain line in FIG. The tip end surface 230d of 230 advances to a position that penetrates a part of the tube wall 1a of the existing tube 1. At this time, the notch stopper 230s in FIG. 22 abuts on the outer peripheral surface of the existing pipe 1. Thus, the cutting with the cutting tool 230 is completed.
[0055]
After this cutting, the operator rotates the sealed case 2 around the existing pipe 1 as shown in FIGS. 23 (b) to 23 (c). As a result, the cutting tool 230 rotates around the axis 233a while rotating about 180 ° (for example, 160 °) along the outer periphery of the existing tube 1 together with the sealed case 2 to cut the existing tube 1 into a semi-annular shape. The cutting groove 12C is formed in the existing pipe 1.
Accordingly, as shown in FIGS. 23C and 24, the cutting tool 230 cuts the existing pipe 1 into a semi-annular shape to form a cutting groove 12 </ b> C in the existing pipe 1. After the cutting is completed, the cutting tool 230 in FIG. 23C is returned to the original position as indicated by a two-dot chain line.
[0056]
Cutting machine removal process
Next, the operator removes the cutting machine 3 in the same manner as in the previous embodiment, and further, as shown in FIGS. 15 and 16, a gate valve 8A is provided at a location corresponding to the cutting groove 12C in the pipe 1A. Insert.
[0057]
Thus, in this piping structure, since the width | variety of the cutting groove 12C of FIG. 15 is small, the sealing case 2 can be reduced in size.
[0058]
By the way, the cutting tool for cutting the cutting groove 12C of the present invention is a truncated cone shape as shown in FIG. 25A, a conical shape as shown in FIG. 25B, or a cylindrical shape as shown in FIG. It may be a shape. Further, as the cutting blade 230f, a large number of diamond particles may be employed as shown in FIGS. 25 (b) and 25 (c) in addition to the carbide chip.
[0059]
Further, as a method of cutting the existing pipe 1, it is not always necessary to rotate the sealed case 2, and as shown in FIG. 25 (d), the substantially cylindrical cutting tool 230 is translated in the circumferential direction R, A cutting groove 12C may be formed. As another cutting method, as shown in FIG. 25E, the cutting groove 12C may be formed by pressing the side surface of a cutting tool 230 made of a cylindrical milling cutter against the existing pipe 1.
[0060]
Next, the gate valve body 8a according to the present invention will be described with different expressions.
The gate valve body 8a enters the existing pipe 1 through an opening (cutting groove) 12C formed in the existing pipe 1 in FIG. 8, and the first rubber packing portion 8d1 of the gate valve body 8a is inserted into the existing pipe 1. The second rubber packing portion 8d2 is in pressure contact with the inner peripheral surface 1b of the existing pipe 1 and is in a valve-closed state. The first rubber packing portion 8d1 cuts the existing pipe 1 in the pipe radial direction C with a cutting tool 230 having a cutting edge 230f along the tip surface 230d and the substantially cylindrical surface of FIG. 3, and thereafter, as shown in FIG. The cutting tool 230 is moved (rotated) along the circumferential direction of the pipe to correspond to the cutting surface 12f in the groove-shaped opening 12C formed over the range of about 180 ° in the circumferential direction of the existing pipe 1. A pressure contact surface.
[0061]
Here, if the cutting groove 12C of FIG. 8 is narrower in the tube axis direction S than the circular opening, the sealing case 2 becomes smaller in the tube axis direction and the area where the gate valve body 8a receives water pressure is reduced. Get smaller. Therefore, in the present invention, the opening 12C is formed in a groove shape narrower in the tube axis direction S than in the tube diameter direction, whereas the first rubber packing portion 8d1 is formed in the groove-shaped opening 12C. It is only necessary to have a shape along the cutting surface 12f.
[0062]
Further, as shown in FIG. 26, the gate valve 8a of the present invention is such that both end portions 8d3 of the first rubber packing portion 8d1 in pressure contact with the cutting surface 12f are in the radial direction with respect to the second rubber packing portion 8d2. The step portion 8d3 has a surface 8d5 that intersects the entry direction C of the gate valve body 8a. Such an intersecting surface 8d5 prevents the existing pipe 1 from being damaged from both end portions of the cutting groove 12C even if it contacts the cutting surface 12f with a large force.
[0063]
As shown in FIG. 9, the first rubber packing portion 8d1 in each of the above embodiments has a pair of first pressure contact surfaces 8d4 in which portions excluding both end portions 8d3 in the tube radial direction are formed along the cross section of the existing tube 1. Have The first rubber packing portion 8d1 has a substantially U-shaped second pressure contact surface 8d5 that connects the two first pressure contact surfaces 8d4 at both end portions 8d3.
In the second pressure contact surface 8d5, the first rubber packing portion 8d1 in FIG. 26 is curved in the tube axial direction S and the pipe circumferential direction R toward the second rubber packing portion 8d2 at both ends in the tube radial direction. It is formed by.
[0064]
By the way, although the example which cuts with the columnar cutting tool 230 was demonstrated in the said Example, you may cut with the disk-shaped cutting tool 230 as shown in FIG.25 (f) in this invention. In this case, as shown in FIG. 26B, both ends of the cutting groove 12C are not U-shaped and have a constant width W, but this case is also included in the scope of the present invention.
[0065]
In each of the above embodiments, the gate valve body 8a is accommodated in the sealed case 2 after cutting. However, in the present invention, the gate valve body 8a may be accommodated in the sealed case 2 before cutting (for example, USP 4,516,598, 1,989,768).
[0066]
Further, in the present invention, after the existing pipe 1 is closed by the gate valve body 8a inserted into the pipe line, the gate valve body 8a is fixed with a stopper bolt, and the valve lid 8b and the valve stem 8c constituting the gate valve 8A, etc. Alternatively, a lid may be attached instead, and the gate valve body 8a may be used as a stopper.
[0067]
Next, another method of using the gate valve body 8a will be described with reference to FIG.
In FIG. 27A, the gate valve body 8a has the first pressure contact surface 8d4 only on one side. Now, a bypass (branch pipe) 300 is connected to the valve 8A. After the gate valve body 8a is lowered and closed, the existing pipe 1 is cut and the mechanical cap 301 shown in FIG. Thereafter, when the gate valve body 8a is raised, the flow of the existing pipe 1 can be set to the bypass 300 side.
That is, the case where the gate valve body 8a has the first pressure contact surface 8d4 only on one side is also included in the scope of the present invention. In other words, the gate valve body 8a does not need to be in contact with all of the cutting surface 12f forming the cutting groove 12C, and may be in contact with only one side.
[0068]
In the present invention, the rubber packing 8d of the gate valve body 8a may also cover both side surfaces 8a3 of the gate valve body 8a of FIG. 26 (a), that is, enter the existing pipe 1 in the gate valve body 8a. The entire portion to be covered may be covered.
[0069]
As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily understand various changes and modifications within the obvious scope by looking at the present specification.
For example, as a prime mover that applies a cutting motion to a cutting tool, an engine or the like may be used in addition to a motor. Alternatively, a prime mover may be installed on the ground, and the power of the prime mover may be transmitted to the cutting tool via a cutter shaft by a flexible shaft. Further, after surrounding an existing pipe with a sealed case, a cutting tool may be attached to the sealed case. Further, after the existing pipe 1 is cut, a branch pipe may be connected to the sealed case via a gate valve.
Further, when cutting an existing pipe with a cutting tool, it is generally preferable to send the cutting tool toward the center in the radial direction of the existing pipe as in the above embodiments, but in the present invention, it is necessary to go to the center. There is no need to send it in the radial direction.
The sealed case may be divided into three or four in the circumferential direction. Further, the valve body may be inserted from any direction such as upward, lateral or downward.
Furthermore, the present invention can be applied not only to water pipes but also to gas pipes. That is, the fluid flowing in the existing pipe is included in the scope of the present invention even if it is other fluid such as gas or oil in addition to water.
Accordingly, such changes and modifications are to be construed as within the scope of the present invention as defined by the claims.
[0070]
【The invention's effect】
As described above, according to the present invention, a cutting tool having an axis set in the radial direction of an existing pipe is sent in the circumferential direction of the existing pipe.Cutting existing pipes into grooves. Therefore, since the peripheral edge of the cutting groove in the existing pipe does not become thin, there is no possibility that the existing pipe is damaged when the valve body is fitted into the cutting groove.
And since there is no possibility of damaging an existing pipe in this way, since a big force can also be added to a sealing surface (pressure contact surface), sealing performance improves.
Further, the hole to be cut in the present invention isSince the width in the tube axis direction is narrower than the circular holeSince the load applied to the gate valve body by the water pressure is reduced, the diameter of the valve stem can be reduced and the sealed case is shortened in the tube axis direction.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a sealed case showing a first embodiment of an existing pipe cutting method according to the present invention.
FIG. 2 is a longitudinal sectional view showing the whole of a sealed case and a cutting machine.
FIG. 3 (a) is a longitudinal sectional view prior to cutting mainly showing a cutting machine. FIG. 3B is a front view of a columnar cutting tool.
FIG. 4 is a longitudinal sectional view after cutting showing a cutting machine.
FIGS. 5 (a), 5 (b), and 5 (c) are process diagrams showing a cutting procedure.
FIG. 6 is a longitudinal sectional view showing a state in which the working upper tank is assembled after cutting.
FIG. 7 is a cross-sectional view showing a state in which the cutting machine is removed.
FIG. 8 is a perspective view showing a valve body and a cutting groove.
FIG. 9 (a) is a side view of the rubber packing. FIG. 9B is a front view of the rubber packing. FIG. 9C is a longitudinal sectional view showing a closed state of the existing pipe. FIG.9 (d) is a cross-sectional view which shows the closed state of the existing pipe.
FIG. 10 is a cross-sectional view showing a state in which a valve body, a valve lid, and the like of a gate valve are accommodated in an upper tank.
FIG. 11 is a cross-sectional view when a valve is inserted.
FIG. 12 is a cross-sectional view showing a completed state.
FIG. 13A is a partial cross-sectional side view of a sealed case according to a second embodiment. FIG. 13B is a bottom view of the second divided case.
14 (a) is a cross-sectional view showing a state in which a sealed case is attached to an existing pipe, and FIG. 14 (b) is a plan view of a second divided case.
FIG. 15 is a longitudinal sectional view showing a completed state when the valve is opened.
FIG. 16 is a cross-sectional view of the same.
FIG. 17 is a longitudinal sectional view showing a completed state when the valve is closed.
FIG. 18 is a cross-sectional view of the same.
FIG. 19 is a cross-sectional view of a sealed case showing a second embodiment of the existing pipe cutting method according to the present invention.
FIG. 20 is a longitudinal sectional view showing the entire sealing case, cutting machine, and the like.
FIG. 21 (a) is a longitudinal sectional view before cutting, mainly showing a cutting machine. FIG. 21B is a cross-sectional view of a columnar cutting tool.
FIG. 22 is a longitudinal sectional view after cutting showing a cutting machine;
FIG. 23 (a), FIG. 23 (b) and FIG. 23 (c) are process diagrams showing a cutting procedure.
FIG. 24 is a longitudinal sectional view showing a state after cutting.
FIG. 25A, FIG. 25B, and FIG. 25C are front views showing modifications of the cutting tool, respectively. FIG. 25D is a cross-sectional view showing another method of forming the cutting groove of the present pipe structure. 25 (e) and 25 (f) are perspective views showing still another method.
26 (a) is a perspective view showing another example of the gate valve body, and FIG. 26 (b) is a perspective view showing another example of the cutting groove.
FIG. 27 is a schematic sectional view showing another example of the piping structure.
FIG. 28 (a) is a sectional view showing a conventional water perforation method. FIG. 28B is a cross-sectional view showing a conventional valve insertion method.
[Explanation of symbols]
1: Existing pipe
1a: Pipe wall
1b: Inner peripheral surface
2: Sealed case
2A: First sealed case
2B: Second sealed case
8A: Gate valve (Valve device for continuous flow insertion)
8a: Gate valve body
8b: Valve lid
8c: Spindle (valve stem)
8d: Rubber packing
8d1: 1st rubber packing part
8d2: Second rubber packing part
12C: Cutting groove
12f: Cutting surface
211: First division case
212: Second division case
212b: Branch part
212d: Movement hole
221: First division case
222: Second division case
222b: Branched portion
230: Cutting tool
230d: tip surface
230e: outer peripheral surface
230f: Cutting blade
231: First motor (for tool rotation)
C: Cutting direction (radial direction)
R: Circumferential direction
S: Pipe axis direction

Claims (1)

The cutting groove enters the existing pipe through the cutting groove formed by cutting the existing pipe, closes the cutting groove, presses against the inner peripheral surface of the existing pipe, and inserts a valve body for closing the existing pipe. A method of forming a valve seat,
Surrounding a part of the existing pipe in an airtight state by a sealing case divided into a plurality in the circumferential direction of the existing pipe,
A columnar cutting tool supported rotatably around an axis set in the radial direction of the existing pipe and having a plurality of cutting blades is housed in the sealed case in a state attached to the sealed case,
While making the cutting tool rotate around the axis with the power of a prime mover and cutting the existing pipe by rotation of the cutting tool,
While sending the cutting tool toward the radial direction of the existing pipe,
By rotating at least a part of the hermetic case in the circumferential direction of the existing pipe, the cutting tool is rotated in the circumferential direction to cause the cutting tool to perform a feed motion, thereby cutting the existing pipe in the cutting direction. A method of forming a valve seat, wherein the cutting is performed over a range of about 180 ° in the circumferential direction by a tool .

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