JP5826682B2 - Corrosion prevention apparatus and corrosion prevention method for pipe cut surface - Google Patents

Description

  The present invention relates to a corrosion prevention apparatus and a corrosion prevention method for preventing corrosion of a pair of pipe cut surfaces formed by full cut cutting of a fluid pipe.

  Conventionally, a construction is known in which an existing water pipe (an example of a fluid pipe) is cut in an indefinite water state and a valve device is attached to the cut portion. As a form of this cutting, there are a perforation that provides an opening on the outer peripheral surface of the water pipe and a cutting that cuts the water pipe in the direction of the pipe axis, so-called full cut cutting. The latter is disclosed in, for example, Patent Documents 1 to 5. ing.

  In such construction, it is preferable that the member is applied to the end face exposed by cutting to prevent corrosion, and in the case of full cut cutting, each of the pair of tube cutting surfaces formed thereby is subjected to corrosion prevention treatment. Is desired. This is because when the pipe cut surface is exposed, rust is generated and mixed into the pipe, or water enters the interface of the lining layer covering the inner surface of the water pipe, resulting in inconvenience. .

  Patent Documents 1 and 2 disclose a method in which a ring-shaped seal member is applied to a pair of tube cut surfaces formed by full-cut cutting to prevent corrosion. However, since this method requires a considerably complicated apparatus and process, it can be said that there are many cases where this method is not suitable for practical use from the viewpoints of economy and workability.

JP 2006-112540 A JP 2006-112541 A JP 2004-60689 A JP 2005-48955 A JP 2006-194344 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a corrosion preventing device for a tube cutting surface capable of simply performing a corrosion preventing treatment on a pair of tube cutting surfaces formed by full cut cutting. It is to provide a corrosion prevention method.

  The above object can be achieved by the present invention as described below. That is, the corrosion preventing device for a pipe cut surface according to the present invention is housed in an outer box that surrounds the outer peripheral surface of the fluid pipe and is mounted between a pair of pipe cut faces formed by full cut cutting of the fluid pipe. A telescopic double cylinder that is disposed, the double cylinder having a corrosion protection body facing the pair of pipe cut surfaces, and a core body inserted into the corrosion protection body; The corrosive body is expanded in diameter by being inserted into the core body and pressed against the pair of pipe cut surfaces, and the side walls of the corrosive body and the core body communicate with the fluid pipe, respectively. A through hole is provided.

  According to this apparatus, by using the nested double cylinder housed in the outer box, it is possible to easily perform the anticorrosion treatment on the pair of tube cut surfaces formed by the full cut cutting. . The double cylinder body has a corrosion prevention body as an outer cylinder and a core body as an inner cylinder, and the corrosion prevention body whose diameter is expanded by inserting the core body is directed to a pair of tube cutting surfaces. Further, a through-hole communicating with the fluid pipe is provided on the side of the corrosion-proof body and the core body, so that the flow path of the fluid flowing in the fluid pipe can be prevented from being obstructed.

  In the corrosion preventing apparatus for a pipe cut surface according to the present invention, it is preferable that the double cylinder body includes a partition body inside the core body that can block or switch a flow path of the fluid flowing in the fluid pipe. An apparatus provided with such a configuration can be used as a valve device attached to a full cut cutting point. If the outer box has a branch portion that opens in a direction that intersects the tube axis direction of the fluid pipe, at least three flow paths are formed from the full-cut cut portion of the fluid pipe. However, the flow path can be blocked or switched by the partition.

  In the corrosion preventing apparatus for a pipe cut surface according to the present invention, it is preferable that the corrosion preventing body is formed of a C-shaped cylinder having a notch at one place in the circumferential direction. Accordingly, the diameter of the corrosion-resistant body can be easily increased by inserting the core body, and the corrosion-resistant body can be accurately applied to the cut surface of the tube. Further, even when the corrosion protection body is made of metal or the like, it can be deformed so as to widen the notch, thereby enabling smooth diameter expansion.

In the corrosion preventing apparatus for a pipe cut surface according to the present invention, the double cylinder can be temporarily held in a state in which only the distal end portion of the core body is inserted into the corrosion prevention body, and the double cylinder is temporarily held. From the state, by pushing the core body while fixing the corrosion-resistant body, the core body is inserted into the corrosion-resistant body, and the diameter of the corrosion-resistant body is increased. Thereby, handling of a double cylinder becomes easy and workability can be improved significantly.

  Further, in the corrosion prevention method for a pipe cut surface according to the present invention, a nested double cylinder having a corrosion prevention body and a core body is accommodated in an outer box that surrounds the outer peripheral surface of the fluid pipe, The core body is inserted between the pair of pipe cut surfaces formed by full-cut cutting of the fluid pipe, and opposed to the pair of pipe cut surfaces, and the core body is expanded by inserting the core body. The corrosion-proof body having a diameter is pressed against the pair of pipe cut surfaces, and a through-hole provided in a side of the corrosion-proof body and the core body is communicated with the fluid pipe.

  According to this method, by using a nested double cylinder housed in the outer box, it is possible to easily apply a corrosion-proof treatment to a pair of tube cut surfaces formed by full cut cutting. . The double cylinder body has a corrosion prevention body as an outer cylinder and a core body as an inner cylinder, and the corrosion prevention body whose diameter is expanded by inserting the core body is directed to a pair of tube cutting surfaces. Further, a through-hole communicating with the fluid pipe is provided on the side of the corrosion-proof body and the core body, so that the flow path of the fluid flowing in the fluid pipe can be prevented from being obstructed.

  In the corrosion prevention method for a tube cut surface according to the present invention, it is preferable that the corrosion prevention body is formed of a C-shaped cylinder having a notch at one place in the circumferential direction. Accordingly, the diameter of the corrosion-resistant body can be easily increased by inserting the core body, and the corrosion-resistant body can be accurately applied to the cut surface of the tube. Further, even when the corrosion protection body is made of metal or the like, it can be deformed so as to widen the notch, thereby enabling smooth diameter expansion.

In the corrosion prevention method for a tube cut surface according to the present invention, the double cylinder is disposed between the pair of tube cut surfaces in a temporarily held state in which only the distal end portion of the core body is inserted into the corrosion preventive body, By pushing in the core body while fixing the corrosion-resistant body, the core body is inserted into the corrosion-resistant body to expand the diameter of the corrosion-resistant body . Thereby, handling of a double cylinder becomes easy and workability can be improved significantly.

Sectional drawing which shows a mode that the corrosion prevention apparatus of a pipe cut surface is attached Schematic which shows the AA arrow cross section of FIG. Perspective view of corrosion protection body Perspective view of core (A) Rear view perspective view, (B) Front view, and (C) Rear view sectional view of a double cylinder in a temporarily held state (A) Back view perspective view, (B) Front view, and (C) Back view cross section of double cylinder Sectional drawing which shows the state which has arrange | positioned the double cylinder between a pair of pipe cut surfaces Sectional drawing which shows the state which addressed the corrosion-proof body to a pair of pipe cut surfaces Half-sectional view showing the completed state Perspective view of partition

  An embodiment of the present invention will be described with reference to the drawings, taking as an example a case where an existing water pipe (an example of a fluid pipe) made of ductile cast iron is subjected to a corrosion-proof treatment in an indefinite water state. The water pipe K shown in FIG. 1 has already been fully cut and cut in the pipe axis direction. Full cut cutting is performed using a drilling machine connected above the work gate valve 5 (hereinafter referred to as the work valve 5), and after the drilling machine is removed, the sealed case 6 is connected to the work valve 5. Yes.

  This anticorrosion treatment includes a nested double cylinder 2 that is accommodated in an outer box 1 that is mounted so as to surround the outer peripheral surface of the water pipe K. The outer box 1 has a split structure that can be externally fitted to the existing water pipe K, and seals the periphery of the full-cut cutting location. The outer box 1 of the present embodiment has a T-shaped tube shape as shown in FIG. 2 and has a branch portion 11 that opens in a direction intersecting the tube axis direction. The branching portion 11 is closed by a flange 12 connected to the flange 12 (removed in FIG. 9).

  The outer box 1 has an upper and lower split structure in which an upper member 13 and a lower member 14 are joined to each other by a fastener 15 (see FIG. 9). Instead of the fastener 15 constituted by a bolt and a nut, it is also possible to join by welding or the like. Such a structure of the outer box 1 is disclosed in, for example, Japanese Patent Application Laid-Open Nos. 2007-187241 and 2011-75052. An opening having a flange 16 is formed in the upper part of the upper member 13, and the cutter of the drilling machine and the double cylinder 2 can be arranged in the outer box 1 through this opening.

  The double cylinder 2 has a corrosion-resistant body 3 as an outer cylinder shown in FIG. 3 and a core body 4 as an inner cylinder shown in FIG. 4, and has a nested structure in which the latter is inserted into the former. It has become. FIG. 5 shows a temporary holding state in which only the tip of the core body 4 is inserted into the corrosion-resistant body 3, and FIG. 6 shows a state where the core body 4 is entirely inserted into the corrosion-resistant body 3. Yes. In FIG. 1, the double cylinder 2 is depicted not by a cross section but by an appearance, and as shown in FIGS. 7 and 8, the double cylinder 2 has a pair of tube cutting surfaces 10 formed by full cut cutting. Arranged between.

  In a state where the double cylinder 2 is disposed between the pair of tube cutting surfaces 10, the corrosion protection body 3 faces the pair of tube cutting surfaces 10. And this double cylinder 2 is comprised so that the diameter of the corrosion prevention body 3 may be expanded by inserting the core 4 in the corrosion prevention body 3, and in FIG. Is pressed and in close contact. Thereby, exposure of a pair of pipe cut surfaces 10 formed by full cut cutting is prevented, and corrosion protection can be performed.

  Through holes 31 and 41 communicating with the water pipe K are provided on the sides of the corrosion-resistant body 3 and the core body 4 so as not to obstruct the flow path of the water flowing in the water pipe K. In FIG. 8, the hole axes of the through holes 31 and 41 substantially coincide with the pipe axis of the water pipe K, and the flow of water passing through these is ensured. The through holes 31 and 41 are provided in a size corresponding to the opening of the tube cutting surface 10 so that the flow rate does not decrease excessively. In addition, regions around the through holes 31 and 41 that press against the tube cutting surface 10 are curved along the tube cutting surface 10. In the present embodiment, flow holes 32 and 42 communicating with the branch portion 11 are also provided on the sides of the corrosion-resistant body 3 and the core body 4.

  The procedure for applying the anticorrosion treatment to the tube cut surface 10 is as follows. First, as shown in FIG. 1, a sealed case 6 containing a double cylinder 2 in a temporarily held state is connected to a work valve 5. Next, as shown in FIG. 7, the double cylinder 2 is lowered and accommodated in the outer box 1, and disposed between the pair of tube cutting surfaces 10. Subsequently, as shown in FIG. 8, the core body 4 is inserted into the corrosion-resistant body 3 opposed to the pair of tube cutting surfaces 10, and thereby the diameter of the corrosion-resistant body 3 is pressed against the pair of tube cutting surfaces 10. The through holes 31 and 41 are communicated with the water pipe K. After removing the working valve 5 and the sealing case 6 from the outer box 1 as shown in FIG. 9, the lid 9 is attached to seal the inside of the outer box 1.

  The double cylinder 2 includes a partition 7 inside the core body 4 that can block or switch a flow path of water flowing in the water pipe K. As shown in FIG. 10, the partition body 7 includes a wall portion 71 that is curved along the inner peripheral surface of the core body 4, and is configured to be rotatable according to the operation of the shaft portion 72. In the present embodiment, since the outer box 1 has the branch portion 11, three flow paths are formed from the full-cut cut portion, and one of the left and right through holes 41 and the flow holes 42 is selectively wall portions. By closing at 71, this flow path can be blocked or switched.

  For example, when water in the water pipe K flows from left to right in FIG. 9, if the wall portion 71 of the partition 7 is arranged on the left and the upstream side of the through hole 41 is closed, the flow path Is cut off. Moreover, if the wall part 71 of the partition 7 is arrange | positioned on the right side and the downstream of the through-hole 41 is obstruct | occluded, it will let water flow through the circulation hole 42 to the branch pipe not shown connected to the branch part 11, The flow path is switched.

  The double cylinder 2 has a cylindrical shape as a whole, and an upper portion thereof is closed with an inner plug 8. As shown in FIGS. 5 and 6, the inner plug 8 is fixed to the core body 4 with bolts 81, and the shaft portion 72 of the partition 7 passes through the center thereof. The partition 7 is rotated by operating the shaft portion 72 protruding from the inner plug 8. The tip of the operating rod 61 that is operated when lowering the double cylinder 2 is attached to the inner plug 8.

  As long as the corrosion-resistant body 3 expands by insertion of the core body 4 and contributes to corrosion prevention by pressing against the tube cutting surface 10, various materials such as rubber, synthetic resin, and stainless steel are used. Can be produced. It is also possible to use a plurality of materials together. For example, the entire body of the anticorrosive body 3 may be made of stainless steel, and rubber may be lined over the entire outer surface or a necessary region. This necessary area includes an area around the through hole 31 that presses against the pair of tube cutting surfaces 10.

  The anticorrosive body 3 of the present embodiment is formed of a C-shaped cylinder having a notch 33 at one place in the circumferential direction. Therefore, the diameter of the corrosion-resistant body 3 is easily increased by the insertion of the core body 4, and the corrosion-resistant body 3 can be accurately applied to the tube cutting surface 10. Moreover, if it is such a shape, even if the corrosion protection body 3 is metal, it will deform | transform so that the notch 33 may be expanded and a smooth diameter expansion will be attained.

  On the outer periphery of the upper portion of the corrosion protection body 3, a flange portion 34 is formed so as to protrude at a position above the through hole 31. In addition, an upper engagement portion 35 having an inclined surface inclined inward toward the insertion direction (downward) of the core body 4 at a position above the through-hole 31 on the upper inner periphery of the corrosion protection body 3. Is formed. Further, a lower engagement portion 36 having a shape similar to that of the upper engagement portion 35 is formed on the lower inner periphery of the corrosion protection body 3 at a position below the through hole 31.

  The core body 4 is made of, for example, ductile cast iron, and the partition body 7 and the inner plug 8 are combined as described above. A flange 44 is formed on the upper outer periphery of the core body 4 at a position above the through hole 41. On the outer periphery of the upper portion of the core body 4, an upper engagement portion 45 having an inclined surface inclined inward toward the insertion direction of the core body 4 at a position above the through hole 41 and below the flange portion 44. Is formed. Furthermore, a lower engagement portion 46 having a shape similar to that of the upper engagement portion 45 is formed on the lower outer periphery of the core body 4 at a position below the through hole 41.

  As described above, the double cylinder 2 can be temporarily held in a state in which only the tip portion of the core body 4 is inserted into the corrosion protection body 3. In the temporarily held state, as shown in FIG. 5, the upper engagement portion 35 of the corrosion-resistant body 3 is engaged with the lower engagement portion 46 of the core body 4. As a result, the corrosion protection body 3 is held in a state of hanging from the core body 4 without dropping. In the present embodiment, an example is shown in which the upper engagement portion 35 of the anticorrosion body 3 protrudes inward, and the lower engagement portion 46 of the core body 4 into which the corrosion prevention body 3 is inserted is recessed inward. The relationship may be the opposite.

  As shown in FIGS. 5 (A) and 6 (A), in the present embodiment, a protrusion 47 that fits into the notch 33 of the corrosion-resistant body 3 is provided on the outer peripheral surface of the core body 4. Thereby, rotation of the corrosion-resistant body 3 can be prevented and relative displacement between the corrosion-resistant body 3 and the core body 4 can be prevented. Such a configuration is useful for appropriately overlapping the through hole 31 and the through hole 41 and the flow hole 32 and the flow hole 42 when the core body 4 is entirely inserted into the corrosion protection body 3.

  When the working valve 5 is opened and the operating rod 61 is pushed down from the state of FIG. 1 to lower the temporarily held double cylinder 2, two parts are interposed between the pair of tube cutting surfaces 10 as shown in FIG. A heavy cylinder 2 is arranged. At this time, the collar portion 34 comes into contact with the upper ends of the pair of tube cutting surfaces 10 from above, and the corrosion protection body 3 is fixed without lowering beyond that. Therefore, by further pressing down the operation rod 61, the core body 4 can be pushed in while the corrosion-resistant body 3 is fixed, and the core body 4 can be inserted into the corrosion-resistant body 3 to increase the diameter of the corrosion-resistant body 3.

  In the present embodiment, since the lower engagement portion 46 and the upper engagement portion 35 that are engaged with each other have an inclined surface that is inclined inward toward the insertion direction of the core body 4, the core is removed from the temporarily held state. When inserting the body 4, it is easy to expand the diameter of the corrosion-resistant body 3. 5 and 7, the outer diameter of the core body 4 is set to be larger than the inner diameter of the anticorrosive body 3 at least in the region around the through holes 31, 41, as shown in FIGS. When the core body 4 is inserted into the corrosion-resistant body 3 as a whole, the diameter of the corrosion-resistant body 3 can be expanded to reach the pipe cutting surface 10.

  In the process of pushing in the core body 4 while fixing the corrosion-resistant body 3, the diameter of the corrosion-resistant body 3 is expanded while expanding the notch 3, and finally the gap of the notch 33 is filled as shown in FIG. Thus, the protrusion 47 is fitted. Thereby, shakiness of the corrosion-resistant body 3 by water pressure can be suppressed. When the collar portion 44 of the pushed core body 4 comes into contact with the collar portion 34, the core body 4 is entirely inserted into the corrosion-resistant body 3 and is subjected to a corrosion-proof treatment. The operations required from the state of FIG. 1 to the state of FIG. 8 are only opening the work valve 5 and pushing down the operating rod 61.

  In the state of FIG. 8, as shown in FIG. 6C, the lower engagement portion 36 of the corrosion prevention body 3 engages with the lower engagement portion 46 of the core body 4, and the upper engagement portion 35 of the corrosion prevention body 3 Engage with the upper engaging portion 45 of the core body 4. Since the engaging portions are set at the upper and lower portions in this way, the relative height position of the corrosion-resistant body 3 with respect to the core body 4 can be appropriately fixed. In the state after completion of the work shown in FIG. 9, the lid body 9 presses the inner plug 8 from above, and the posture of the double cylinder body 2 is stable.

  The present invention is not limited to the embodiment described above, and various improvements and modifications can be made without departing from the spirit of the present invention.

  In the above-described embodiment, the example in which the three-way flow path is formed from the full cut cut portion is shown, but the present invention is applicable even when the two or four or more flow paths are formed from the full cut cut portion. Is applicable. However, in the case where the double cylinder is provided with a partition body, it is preferable that at least three flow paths are formed from the full-cut cutting portion in order to enhance its practicality.

  In the above-described embodiment, the example in which the collar 34 is brought into contact with the upper end of the pipe cutting surface 10 when the temporarily held double cylinder is lowered has been described. It is not restricted to what fixes the corrosion-resistant body 3 positioned relatively with respect to the water pipe K to the insertion direction of the core body 4 by making it contact | abut to the pipe body of the water pipe K. Therefore, for example, the corrosion-resistant body 3 is fixed in the insertion direction of the core body 4 by bringing the corrosion-resistant body 3 into contact with the outer box 1 such as bringing the lower end of the corrosion-resistant body 3 into contact with the bottom of the tube of the outer box 1. Also good.

  In the above-mentioned embodiment, although the example which installs the double cylinder 2 which incorporated the rotational partition 7 immediately after full cut cutting | disconnection was shown, this invention is not limited to this. For example, if the valve device is installed inside the outer box that has been fully cut and the pipe cut surface needs to be subjected to anticorrosion treatment, the existing valve device is removed and the above-mentioned valve device is removed. You may install such a double cylinder. Further, when the flow path to be blocked is fixed, the partition body may be fixed and provided integrally with the core body. The structure of a partition is not specifically limited, For example, you may comprise with the curved pipe which connects one of a through-hole and a through-hole.

  The present invention can be applied to water pipes, but is not limited to this, and can be widely applied to fluid pipes used for various liquids other than water, such as gas.

DESCRIPTION OF SYMBOLS 1 Outer box 2 Double cylinder 3 Corrosion-proof body 4 Core body 7 Partition body 8 Inner plug 10 Pipe cutting surface 11 Branch part 31 Through-hole 33 Notch 41 Through-hole K Water pipe (an example of a fluid pipe)

Claims (5)

It is housed in an outer box that surrounds the outer peripheral surface of the fluid pipe, and includes a telescopic double cylinder disposed between a pair of pipe cut surfaces formed by full cut cutting of the fluid pipe,
The double cylinder has a corrosion protection body facing the pair of pipe cutting surfaces and a core body inserted into the corrosion protection body, and the corrosion protection body is in a state where the core body is inserted into the corrosion protection body. Diameter increase ,
On the sides of the anticorrosive body and the core body, through holes communicating with the fluid pipes are provided ,
The double cylinder body can be temporarily held in a state where only the tip of the core body is inserted into the anticorrosion body,
An upper engaging portion having an inclined surface inclined inward toward the insertion direction of the core body is formed at a position above the through-hole on the upper inner periphery of the corrosion-proof body,
An upper engaging portion having an inclined surface inclined inward in the insertion direction of the core body is formed on the upper outer periphery of the core body at a position above the through hole. A lower engagement portion having an inclined surface inclined inward toward the insertion direction of the core body is formed on the lower outer periphery at a position below the through hole,
In the state where the double cylinder body is temporarily held, the upper engagement portion of the corrosion prevention body is engaged with the lower engagement portion of the core body, and in the state where the core body is inserted into the corrosion prevention body, the corrosion prevention body. An anticorrosion device for a tube cut surface, wherein an upper engaging portion engages with an upper engaging portion of the core body .   2. The corrosion preventing device for a pipe cut surface according to claim 1, wherein the double cylinder includes a partition body that can block or switch a flow path of a fluid flowing in the fluid pipe inside the core body.   The corrosion preventing apparatus for a pipe cut surface according to claim 1 or 2, wherein the corrosion preventing body is formed of a C-shaped cylinder having a notch at one place in a circumferential direction. A tentative double cylinder having a corrosion-proof body and a core body is accommodated in an outer box that surrounds the outer peripheral surface of the fluid pipe, and only the tip of the core body is inserted into the corrosion-proof body. In a state of holding , disposed between a pair of pipe cut surfaces formed by full cut cutting of the fluid pipe,
The core body is inserted into the corrosion protection body facing the pair of tube cutting surfaces by pressing the core body while fixing the corrosion protection body, and the corrosion protection body expanded in diameter by the insertion of the core body. together pressed against the pair of tubes cut surface, a through hole is provided on the side of the corrosion protection body and the core body is in communication with the fluid conduit,
In a state where the double cylinder body is temporarily held, the upper engagement portion formed on the upper inner periphery of the corrosion-resistant body is engaged with the lower engagement portion formed on the lower outer periphery of the core body, thereby Hold the anticorrosive body hanging from the core body,
In the state where the core body is inserted into the corrosion-resistant body, the upper engagement portion of the corrosion-resistant body is engaged with the upper engagement portion formed on the upper outer periphery of the core body,
The upper engagement portion of the corrosion-proof body, and the lower engagement portion and the upper engagement portion of the core body each have an inclined surface inclined inward toward the insertion direction of the core body . Corrosion protection method. The pipe corrosion prevention method according to claim 4 , wherein the corrosion protection body is formed of a C-shaped cylindrical body having a notch at one place in a circumferential direction.