JP2012062943A - Curable inorganic filler, oil leakage prevention method, and oil leakage prevention kit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent oil leakage occurring at a narrow position, and to perform early repair.SOLUTION: An oil leakage prevention method includes: a mold frame forming step which forms a cylindrical mold frame 50 for surrounding a joint 30 of piping 21, 22 forming an oil passage; a filling step which pours and fills an inorganic filler U from an opening 57 formed at the mold from 50; and a curing step which cures the inorganic filler U in the mold frame 50. In the mold frame forming step, disk-shaped end plates 51, 52 larger in diameter than the joint 30 are attached on the piping 21, 22, after that, both ends of one sheet material 55 are pasted to external peripheral faces of the end plates 51, 52 while cylindrically bending the sheet material, and thus the cylindrical mold frame 50 is formed.

Description

  The present invention relates to a technique for stopping oil leakage in piping forming an oil passage.

  A packing is inserted in the joint of the oil-filled electrical device to ensure airtightness. However, there is a case in which airtightness becomes insufficient due to a defect in the packing, leading to oil leakage. Patent Document 1 listed below discloses a method for oil-sealing by applying a sealing agent 200 in which a curing agent is mixed in a liquid epoxy resin to a joint 230 and sealing it.

JP-A-8-111318

  In the construction method in which the sealing agent 200 is applied to the oil leakage location to stop the oil, if there is an application error even at one location, the oil leaks from there. For this reason, it is difficult to securely stop the oil in a narrow portion where it is difficult to secure a work space.

  Moreover, since the sealing agent 200 has a high viscosity, even if it is applied with a spatula, it does not reach the inside of the minute scratches 210 and irregularities on the joint surface, and a gap is easily formed (see FIG. 20). Therefore, it is necessary to perform a cleansing work (base work) to remove the paint on the repaired part and polish the surface to a flat surface so that there is no gap. However, keren work (underground work) requires skilled skills, so it is necessary to request work from a specialist. For this reason, there is a problem that it may take several months from when the work is ordered to when the work is carried out, and it is not possible to repair the leaked part at an early stage.

  The present invention has been completed based on the above circumstances, and it is an object of the present invention to reliably stop oil leakage occurring in a narrow space and to enable early repair.

  The invention according to claim 1 is an oil leakage prevention method, a mold forming step for forming a cylindrical mold that surrounds a joint of a pipe forming an oil passage or a valve provided in the pipe, and the mold A filling step of pouring a curable inorganic filler into the mold from an inlet formed in the frame, and a curing step of curing the curable inorganic filler in the mold. In the mold forming step, an end plate larger than the outer shape of the joint or valve is mounted on the pipe at a predetermined distance on both sides of the joint or valve, and then one sheet material is bent into a cylindrical shape. However, it is characterized in that a cylindrical formwork having the one sheet material as an outer peripheral wall and the end plate as an end surface is formed by bonding both end portions in the width direction to the outer peripheral surface of each end plate. Have.

  In the present invention, when an inorganic filler is poured into a mold, the inorganic filler spreads in the mold and surrounds the joints and valves. Thereafter, the inorganic filler is cured by a hydration reaction. Thereby, the hardened inorganic filler covers the entire joint and valve to stop the oil. As described above, in the present invention, the inorganic filler is distributed around the joint and the valve by utilizing the fluidity of the inorganic filler itself. Therefore, even if it is a narrow part where the work space is narrow, as long as it is poured into the mold, it is possible to spread the inorganic filler around the joints and valves, and oil leakage can be reliably stopped.

  Further, in the present invention, the mold is manufactured by the minimum number of operations, that is, the operation of attaching the end plate on the pipe and the operation of attaching the sheet material to the outer peripheral surface of the end plate while bending the sheet material into a cylindrical shape. it can. Therefore, the work efficiency is good for the mold manufacturing work. Further, since the outer peripheral wall is formed of a single sheet material, there are few seams, and the liquid leakage of the inorganic filler with respect to the mold can be minimized. Therefore, the amount of the inorganic filler introduced into the mold can be minimized.

  Moreover, since the inorganic filler poured into the mold has a low viscosity and high fluidity, it enters the inside of minute flaws and irregularities on the joint surface and fills the gap. Therefore, the oil passage cannot be made even if the surface scratches and irregularities are not polished. From the above, it became possible to abolish keren work, and even inexperienced workers could easily perform repair work.

As an embodiment of the oil leakage stopping method of the present invention, the following configuration is preferable.
In the mold forming step, the end plate is formed by overlappingly winding an adhesive tape on the outer peripheral surface of the pipe. If it does in this way, the magnitude | size of an end plate can be changed freely by adjusting the winding number of an adhesive tape. Therefore, there is no need to provide a dedicated end plate for each joint or valve size, and cost merit is high.

-A self-fusing tape is wound around the outer peripheral surface of the joint to temporarily seal the mating surface of the joint. In this way, oil can be prevented from leaking to the mold side while the curable inorganic filler is cured in the mold.

  The present invention is a curable inorganic filler used for oil leakage prevention, in which a synthetic resin emulsion is mixed with an inorganic binder containing gypsum and cement, and has a viscosity of 1000 to 20000 mPa · s. (B-type viscometer, 23 ° C., No. 3, rotor, 20 rpm, 60 seconds), characterized in that the setting time at 23 ° C. is 20 minutes to 120 minutes. When the viscosity is in the above range, the filling property to the mold is good and the material is not separated. Moreover, if the setting period is in the above range, the filling property is good, and it is possible to suppress oil floating. Further, throughout the present specification, a case where the viscosity is 20000 mPa · s or less is referred to as low viscosity. Moreover, the cement said here includes both a hydraulic cement and a pneumatic cement.

  As an embodiment of the inorganic filler of the present invention, the weight ratio P / C between the resin solid content of the synthetic resin emulsion and the inorganic binder is preferably 0.15 to 0.6.

  According to the present invention, it is possible to reliably stop oil leakage that occurs in narrow spaces, and early repair is possible.

The figure which shows the part structure of the oil leak stop kit in Embodiment 1. Front view of oil-filled transformer Perspective view showing the structure of the joint Perspective view showing joint cleaning work A perspective view showing a state where a curing tape is wound around a pipe Perspective view showing work of winding backup tape around piping The perspective view which shows the state which attached the end plate to the both sides of a coupling Plan view of FIG. The perspective view which shows the state which affixed the self-fusing tape on the outer peripheral surface of the joint Perspective view showing assembly work of sheet material Perspective view showing a completed formwork Plan view of FIG. The perspective view which shows the operation | work which pours an inorganic type filler into a formwork The perspective view which shows the state which the inorganic type filler hardened | cured within the formwork The perspective view which shows the state which removed the formwork Front view of oil-filled electrical equipment The perspective view which shows the state which the formwork completed in Embodiment 2. The perspective view which shows the state which inserted the funnel in the inlet of the formwork The figure which shows the example which forms an end plate from two semicircle plates Enlarged view of the joint surface

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS.
1. Composition and conditions of curable inorganic filler U Inorganic filler U is a powdery main material (inorganic binder with fillers, additives, etc.) U1, mixed liquid (synthetic resin emulsion) Additives, etc.) U2, kneaded with water if necessary. The inorganic binder is a mixture of gypsum (half-water gypsum) with hydraulic cement or pneumatic cement, and the inorganic filler U is cured by hydration after kneading. The inorganic filler U is a kind of polymer cement.

  The use of the inorganic filler U is to prevent oil leakage that occurs at joints of pipes that form an oil passage, and when the mold 50 is filled and cured, the entire oil leakage location must be covered and sealed. should not. For this reason, the inorganic filler U needs to have low viscosity and high fluidity so that there is no poor filling of the mold 50. On the other hand, there is a problem of material separation and a problem of working time, so that the curing is not caused. If it is too fast or too slow, it does not meet the usage conditions.

  The viscosity of the inorganic filler U can be adjusted by the blending ratio of gypsum and cement and the amount of the viscosity modifier. The setting time of the inorganic filler U is determined by the value of P / C and the setting retarder. It is possible to adjust by the amount. P / C is the weight ratio of the resin solid content P of the synthetic resin emulsion to the inorganic binder C.

  Therefore, the applicant prepared samples having different viscosities and setting times for the inorganic filler U, verified and evaluated whether or not the formability of the mold 50 was separated and whether or not the material was separated. The knowledge that it can be used for oil leakage prevention was obtained.

(1) Viscosity after kneading is 1000 to 20000 mPa · s (B-type viscometer, 23 ° C., No. 3 rotor, 20 rpm, 60 seconds)
(2) The setting time at 23 ° C. is 20 minutes to 120 minutes. The setting time here means the end time of setting.

  The condition (1) is that when the viscosity exceeds the upper limit (20000 mPa · s), the filling property to the mold 50 is deteriorated, and when the viscosity is lower than the lower limit (1000 mPa · s), the material is separated and gypsum is removed. It is because it sinks. And as a more preferable viscosity condition, it is 1200-15000 mPa * s, and if a viscosity exists in the range, a filling property will be very favorable and there will be no separation of a material at all.

  Also, the condition (2) is that if the setting time exceeds the upper limit (120 minutes), the oil leaking from the repair site in the process of hardening rises into the inorganic filler U and passes through the oil passage. Because it makes it. Moreover, if the setting time exceeds the lower limit (20 minutes), the viscosity increases immediately after mixing the main material U1 with the admixture U2 and water, and the filling ability to the mold 50 decreases. A more preferable setting time condition is 30 minutes to 90 minutes. If the setting time is within the range, the filling property is extremely good, and it is possible to substantially suppress oil floating.

  Table 1 shows the compounding ratio (weight ratio), P / C, viscosity, and setting time for the samples used for the verification and evaluation of the conditions (1) and (2). As shown in Table 1, Formulation 1 to Formulation 5 satisfy the conditions of viscosity and setting time, and can be used for oil leakage prevention. Although Formulation 6 satisfies the viscosity condition, it cannot be used because the setting time is 120 minutes or longer.

  In Formulation 1 to Formulation 6, the gypsum (half-water gypsum) used was a sieve having a sieve (screen) having a mesh size of 90 μm and a residue of 1 w% or less. White cement (white Portland cement) was used as the cement. The synthetic resin emulsion is an acrylic resin emulsion having a resin solid content of 50 w% and an average particle size of 0.2 to 0.3 μm. In addition, the additive includes a water reducing agent, a viscosity adjusting agent, a curing retarder, and the like.

  The viscosity was measured with a B-type viscometer (measurement conditions: 23 ° C., No. 3, rotor, 20 rpm, 60 seconds). The setting time is the setting time of the setting measured according to the “setting test” of JIS-R5201 (measurement condition: 23 ° C., but the measurement was performed every 5 minutes).

  Next, the oil permeability performance test will be described. In the oil permeability test, a test piece prepared using the materials of Formulation 1 to Formulation 6 was attached with a glass tube on the surface and poured oil after 2 days from the production, and after a certain period (after 1 month). The degree of penetration is evaluated. The test specimen was a 10 cm × 10 cm plate, and the thickness was 3 patterns of 2 mm, 5 mm, and 10 mm. The oil used was a lubricating oil for machinery having a low viscosity (ISO viscosity standard VG22).

  The oil permeability test was as follows (see Table 2). In the test bodies 1 to 3, the oil oozes out from the back surface of the test body, resulting in NG. In addition, the specimen 5 was slightly discolored on the back surface of the specimen. The other specimens were OK with no oil penetration.

  From the above, it was found that the greater the thickness of the inorganic filler U, the harder the oil penetrates. Further, it was found that when the amount of the synthetic resin emulsion U2 is increased (P / C is large), the oil becomes difficult to penetrate.

  Next, the oil resistance performance test will be described. In the oil resistance test, a specimen prepared using the materials of Formulation 1 to Formulation 6 is immersed in oil three days after the preparation, and the state of the specimen is evaluated after a certain period (after one month). is there. The specimen was a plate of 10 cm × 10 cm × 5 mm.

  The oil resistance test was as follows (see Table 3). It was found that none of the test bodies a to e was altered and had sufficient oil resistance. Moreover, the test body f was softened. Therefore, it was found that the oil resistance decreases when the amount of the synthetic resin emulsion is increased (P / C is large).

  Therefore, in order to satisfy both the impermeability and the oil resistance, the thickness of the inorganic filler U should be 5 mm or more, and P / C should be 0.15 to 0.60 (Formulation 2 to Formulation 5). I understood that. Further, the range of P / C is more preferably 0.15 to 0.45, and oil resistance is further enhanced by using the range.

2. Oil leak stop kit Z
The oil leakage stopping kit Z is composed of the following materials (a) to (g) (see FIG. 1).
(A) Powdery main material U1 in which filler (calcium carbonate) and additives are added to an inorganic binder containing gypsum and cement
(B) Admixture (synthetic resin emulsion, water, additive) U2
(C) Sheet material 55
(D) Backup tape (corresponding to “adhesive tape” of the present invention) 45
(E) Curing tape 42
(F) Self-bonding tape 47
(G) Others (cleaning spray 41, primer 44)

3. Oil Leakage Stopping Method Next, an oil-filled transformer will be exemplified to explain the oil leak stoppage method using the oil leak stop kit Z. As shown in FIG. 2, the oil-filled transformer 10 includes a device main body 11 that houses a transformer, a conservator 12, a bushing 13, and a radiator 15. A pair of upper and lower pipes (pipes that form an oil passage) 21 and 22 are passed between the equipment body 11 and the radiator 15, and the insulating oil in the equipment body 11 is circulated to the radiator 15 side for cooling. It is the composition which makes it.

  Each piping 21 and 22 is couple | bonded with the other piping via the coupling 30 which fastened two flanges F1 and F2 with the volt | bolt BT (refer FIG. 3). Such a joint 30 seals the mating surface G of the flanges F1 and F2 with a packing interposed between the flanges F1 and F2 to prevent oil leakage. However, since the packing heat shrinks with changes in the outside air temperature, there are cases where the airtightness becomes insufficient and oil leakage occurs. Hereinafter, how to stop the oil leakage will be described with reference to an example in which the oil leakage occurs in the joint 30 provided on the pipe 21.

  When oil leakage occurs, first, as shown in FIG. 4, after spraying a cleaning agent on the surface of the joint 30 and the pipes 21 and 25 with the spray 41, the cleaning agent is wiped off with a waste cloth, and the joint 30 and the pipes 21 and 25. Work to remove the oil and dirt on the surface.

  When the dirt is removed, a cylindrical mold 50 surrounding the joint 30 is created. For this purpose, first, the curing tape 42 is wound and pasted to the pipes 21 and 25 on both sides of the joint at a predetermined distance from the joint 30 (see FIG. 5). The curing tape 42 makes it easy to remove the formwork 50 (to make it easy to peel off the backup tape 45 described below), so that the curing tape is preferably weak and the width is about twice that of the backup tape 45. preferable.

  When the curing tape 42 is pasted, the primer (primer) 44 is applied to the surfaces of the joint 30 and the pipes 21 and 25 using a brush. The reason why the primer 44 is applied is to improve the adhesion of the inorganic filler U to the joint 30 and the pipes 21 and 25.

  Next, on both sides of the joint 30, an operation of making circular end plates 51 and 52 at a certain distance from the joint 30 is performed. In this embodiment, circular end plates 51 and 52 are made by wrapping a backup tape 45 provided with an adhesive layer on the back surface of the base material on the curing tape 42 (FIGS. 6 and 7). reference).

  The end plates 51 and 52 form the end surface of the mold 50 and need to be larger than the outer periphery of the joint 30. In this example, the sizes of the left and right end plates 51 and 52 are made larger than the outer shape of the joint 30 by about 10 mm so that the thickness of the inorganic filler U that cures in the mold 50 is secured about 10 mm. 8).

  The base material 46 of the backup tape 45 was made of a flexible material (for example, foamed polyethylene) in consideration of workability, and had a thickness of about 1 mm and a width of about 15 mm. Further, the backup tape 45 may be a tape having strong adhesive strength so that the shape of the backup tape 45 does not collapse or peel off during the lap winding.

  And if the operation | work which produces the end plates 51 and 52 is completed, the operation | work wound around the outer peripheral surface of the coupling 30 will be performed, next pulling and extending the self-fusing tape 47. FIG. Thereby, the outer peripheral surface of the joint 30 is covered with the self-bonding tape 47, and the mating surfaces G of the flanges F1 and F2 are temporarily sealed (see FIG. 9).

  Next, an operation for processing the sheet material 55 which becomes the outer peripheral wall of the mold 50 according to the size of the end plates 51 and 52 is performed. Specifically, the lateral width L1 is processed to have the same dimension as the pitch P1 between the end plates 51 and 52, and the total length L2 is processed to be shorter by about 5 to 10 cm than the peripheral length of the end plates 51 and 52 (see FIG. 10). ). The reason why the total length L2 of the sheet material 55 is shorter than the peripheral length of the end plates 51 and 52 is that it is necessary to make an opening 57 for pouring the inorganic filler U.

  And if it can process, the operation | work which affixes a double-sided adhesive tape on the both edges (both edges of the width direction) of the sheet material 55, and forms the adhesion layer 56 will be performed. The sheet material 55 is preferably a flexible material. In this example, a PP sheet (polypropylene sheet) having a thickness of about 0.5 mm was used.

  Next, an operation of bonding the processed sheet material 55 to the two end plates 51 and 52 is performed. For this purpose, first, the processed sheet material 55 is made to enter the lower side of the joint 30 with the adhesive layer 56 facing upward, and the adhesive layers 56 on both sides in the width direction as shown in FIG. Position it so that it is directly below 52. Thereafter, the sheet material 55 is slowly lifted and brought into contact with the lower ends of the two end plates 51 and 52 from below.

  After that, the front and rear sides of the sheet material 55 are rolled up. Accordingly, both edge portions of the sheet material 55 are bonded to the outer peripheral surfaces of the end plates 51 and 52 via the adhesive layer 56. Thus, as shown in FIGS. 11 and 12, a cylindrical formwork (one sheet material 55 is attached to the outer peripheral wall) having an opening 57 (corresponding to the “injection port” of the present invention) 57 at the upper end portion of the outer peripheral wall. As a result, a cylindrical mold form 50 having end plates 51 and 52 as end faces is completed (form form forming step).

  When the mold 50 is completed, next, as shown in FIG. 13, the inorganic filler U is poured from the opening 57 at the upper part of the mold to fill the mold 50 (filling step). The composition of the inorganic filler U is composition 2 in Table 1, and the viscosity after kneading at 23 ° C. is 1550 mPa · s. Accordingly, the fluidity is high, and the inorganic filler U spreads to every corner in the mold 50 after filling, and surrounds the joint 30 without a gap.

  Then, after the work of filling the inorganic filler U into the mold 50 is completed, it is only necessary to wait for the filled inorganic filler U to be cured by the hydration reaction. In this example, the inorganic filler U of Formulation 2 shown in Table 1 is used, and the setting time (end time) is about 45 minutes. Therefore, when about 45 minutes have passed after mixing the admixture U2 and water with the main material U1 and kneading, the inorganic filler U condenses, and then the curing reaction proceeds to become a cured body, covering the entire joint 30. The sealing layer Z is formed (curing step).

  From the above, the joint 30 is sealed with the sealing layer Z, so that the oil is stopped. In order to remove the formwork 50, it is only necessary to peel off the backup tape 45 together with the curing tape 42 after peeling off the sheet material 55, whereby a sealing layer covering the entire joint 30 as shown in FIG. Only the mold 50 can be easily removed from Z.

4). Description of Effect In the oil leakage prevention method of the present embodiment, the sealing layer Z that covers the entire joint 30 is formed by filling the mold 50 with the inorganic filler U and curing it in the mold 50. To do. And since the inorganic type filler U is low-viscosity and has high fluidity, it enters the inside of minute scratches and irregularities on the joint surface and fills the gaps. From the above, the oil passage cannot be made without polishing the surface scratches and irregularities. As a result, it became possible to abolish keren work, and even inexperienced workers could easily perform repair work. From the above, repair was possible at an early stage after the occurrence of oil leakage.

  In the conventional method of applying a sealing agent to the outer peripheral surface of the joint 30, if there is an application error even at one location, oil leaks from there. On the other hand, the structure of the oil-filled electrical device is various, and as shown in FIG. 16, the radiator 80 may be disposed adjacent to the device body 70. As described above, the narrow space where the walls of the equipment are adjacent has no working space, and it has been difficult to reliably stop the oil by the conventional construction method.

  In this regard, in the oil leakage stopping method of the present embodiment, the sealing layer Z that covers the entire joint 30 is formed by using the fluidity of the inorganic filler U. Therefore, even if it is a narrow place where it is difficult to secure a work space, if the mold 50 is made accurately, the sealing layer Z is formed according to the form of the mold simply by pouring the inorganic filler U. And covers the entire joint 30. Accordingly, it is possible to reliably stop oil leakage.

  Further, in the oil leakage stopping method according to the present embodiment, the mold 50 is subjected to the minimum number of operations, that is, the work of attaching the disk-shaped end plates 51 and 52 onto the pipes 21 and 25, and the sheet material 55 to the end plate 51, It can be manufactured by two operations of bonding to the outer peripheral surface of 52. Therefore, the work efficiency is good for the mold making operation. Further, the outer peripheral wall of the mold 50 is made of a single sheet material 55, and there are few seams. Therefore, liquid leakage of the inorganic filler U with respect to the mold 50 can be minimized. Therefore, the input amount of the curable inorganic filler U to the mold 50 can be minimized.

  Further, in the oil leakage stopping method of the present embodiment, the end plates 51 and 52 are formed by overlappingly winding the backup tape 45. Therefore, the size of the end plates 51 and 52 can be changed according to the size of the joint 30 by changing the number of turns of the backup tape 45 according to the size of the joint 30. Therefore, it is not necessary to provide dedicated end plates 51 and 52 for each type and size of the joint 30 and the pipe 21, and cost merit is high.

  Further, if a large amount of oil leaks from the joint 30 while the curable inorganic filler U filled in the mold 50 is cured, an oil passage is formed in the sealing layer Z, and the oil leaks from there. End up. In this respect, in the oil leakage prevention method of the present embodiment, the self-bonding tape 47 is attached to the outer peripheral surface of the joint 30 to temporarily seal the mating surface of the joint 30, while the inorganic filler U is cured. Was prevented from leaking out to the mold 50 side. Therefore, it is not possible to make the oil passage in the sealing layer Z. Therefore, it is possible to reliably stop oil leakage.

  In addition, when the packing that causes the oil leakage is changed according to the use situation, it is necessary to remove the sealing layer Z. In this respect, in the present embodiment, the main component of the inorganic filler U is gypsum, and can be destroyed relatively easily if an impact is applied. Therefore, the sealing layer Z can be easily removed.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIGS. Embodiment 2 demonstrates the case where the direction of piping 121,125 of repair object is an up-down direction. Also in this case, when oil leakage occurs, an operation of removing oil and dirt on the surfaces of the joint 130 and the pipes 121 and 125 is first performed.

  Thereafter, the curing tape 42 is affixed to the pipes 121 and 125 on both sides of the joint, and the backup tape 45 is overwrapped on the curing tape 42 so that the circular ends are separated by a certain distance on both sides of the coupling 130. An operation of making the plates 151 and 152 is performed.

  Then, after the end plates 151 and 152 are formed, the sheet material 155 is processed into a predetermined size, and the end plates 151 and 152 are bonded to the end plates 151 and 152 while being rounded. At this time, the front end 155F and the rear end 155R of the sheet material 155 are brought into contact with each other and closed with a vinyl tape 160 or the like so that a gap is not formed on the outer peripheral surface of the mold 150.

  Next, an inlet 157 is opened in the upper end plate 151 shown in FIG. 17 with a cutter or the like. Thereafter, the inorganic filler U is poured into the funnel 170 inserted into the injection port 157 to fill the mold 150 with the inorganic filler U. Thereafter, the filled inorganic filler U is cured in the mold 150 by a hydration reaction and covers the entire joint 130 to form the sealing layer Z. From the above, even when the direction of the pipe 121 is in the vertical direction, the oil leakage can be stopped as in the first embodiment.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  (1) In the first embodiment, the transformer is illustrated as an example of the oil-filled electrical device. However, the transformer is applicable as long as the device is cooled and insulated using the insulating oil. It can be used for oil containers and oil-filled switches. In addition, any device that uses oil can be used.

  (2) In Embodiment 1 described above, the oil leakage prevention method of the present invention has been described by taking as an example the case where oil leakage has occurred in a joint that joins pipes. It can also be applied to the case where oil leakage occurs in the valve provided in the above. That is, a cylindrical mold is formed so as to surround the valve, and a curable inorganic filler U is poured into the mold to be cured.

  (3) In the first embodiment, the example in which the end plates 51 and 52 are formed by overlappingly winding the backup tape 45 is shown. The end plates 51 and 52 can be formed by abutting two semicircular plates 81 and 82, for example, as shown in FIG. . Further, the shape of the end plate is not necessarily circular as long as it has a smooth outer shape (curved shape) with no corners.

  (4) In the first embodiment, as an example of the backup tape 45, the base material is made of foamed polyethylene. However, for example, compressed urethane or the like can also be used.

  (5) In the first embodiment, a PP sheet is illustrated as an example of the sheet material 55, but, for example, a PET sheet, a thin metal sheet, or the like can be used.

  (6) In the first embodiment, an acrylic resin emulsion is exemplified as an example of the synthetic resin emulsion. However, a resin that is usually used by mixing with an inorganic binder such as cement can be used. For example, emulsions such as vinyl acetate resin, carboxylic acid vinyl resin such as ethylene vinyl acetate resin, urethane resin, and epoxy resin can be used.

  (7) In the said Embodiment 1, what mix | blended white cement (white Portland cement) with hemihydrate gypsum was illustrated as an example of an inorganic type binder. The cement blended in the hemihydrate gypsum is not limited to white cement, and hydraulic cements and pneumatic cements exemplified below can be used. Various hydraulic cements include ordinary Portland cement, early-strength Portland cement, ultra-early strong Portland cement, medium heat Portland cement, low heat Portland cement, sulfate-resistant Portland cement, blast furnace cement, fly ash cement, alumina cement, etc. It can be used. Moreover, gypsum, slaked lime, dolomite plaster, etc. can be used as the air-hardening cement.

DESCRIPTION OF SYMBOLS 21 ... Piping 30 ... Joint 42 ... Curing tape 45 ... Backup tape (equivalent to "adhesive tape" of this invention)
47 ... Self-bonding tape 50 ... Formwork 51, 52 ... End plate 55 ... Sheet material 57 ... Opening (corresponding to "injection port" of the present invention)
F1, F2 ... Flange Bt ... Bolt U ... Inorganic filler

Claims (6)

Oil leakage prevention method,
A formwork forming step for forming a tubular formwork surrounding a valve provided on a joint or pipe for forming an oil passage;
A filling step of filling the mold by pouring a curable inorganic filler into the mold from an inlet formed in the mold;
Curing the curable inorganic filler in the mold, and
In the mold forming step, an end plate larger than the outer shape of the joint or valve is mounted on the pipe at a predetermined distance on both sides of the joint or valve, and then a sheet material is bent while being bent into a cylindrical shape. A cylindrical formwork having the one sheet material as an outer peripheral wall and the end plate as an end surface is formed by bonding both end portions in the direction to the outer peripheral surface of each end plate. Oil stop method.   The oil leakage prevention method according to claim 1, wherein, in the mold forming step, the end plate is formed by overlappingly winding an adhesive tape around an outer peripheral surface of the pipe.   The oil leakage prevention method according to claim 2, wherein a self-fusing tape is wound around the outer peripheral surface of the joint to temporarily seal the mating surface of the joint. A curable inorganic filler used to stop oil leakage,
A synthetic resin emulsion is mixed with an inorganic binder containing gypsum and cement.
The viscosity is 1000-20000 mPa · s (B-type viscometer, 23 ° C., No. 3, rotor, 20 rpm, 60 seconds),
A curable inorganic filler characterized in that the setting time at 23 ° C. is 20 minutes to 120 minutes.   The inorganic filler according to claim 4, wherein the weight ratio P / C of the resin solid content of the synthetic resin emulsion to the inorganic binder is 0.15 to 0.6. An oil leakage stop kit,
An inorganic binder containing gypsum and cement;
A synthetic resin emulsion;
A sheet material that forms an outer peripheral wall of a mold that is filled with a curable inorganic filler obtained by mixing the synthetic resin emulsion with the inorganic binder;
An oil leakage stopping kit comprising: an adhesive tape that forms an end plate of the mold that is filled with the curable inorganic filler.

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