JP2014077454A - Liquid leakage prevention method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent oil leakage from a flange part used in electric power equipment, in particular, oil leakage from an annular contact line that is a border dividing two pipe flanges.SOLUTION: An oil leakage prevention method includes: a first step where a contact line 102C that is a liquid leakage prevention portion is covered by a filamentous material; and a second step where a side surface 102A of a pipe flange 102F, which is a prevention target area including the liquid leakage prevention portion covered by the filamentous material, is sealed by a seal material 14a in a fluid-tight manner.

Description

  The present invention relates to a liquid leakage prevention method suitable for oil leakage prevention from electric power equipment using high-pressure insulating oil such as an oil-filled transformer or oil breaker.

  In substations and the like of electric power companies, power equipment (hereinafter also referred to as oil-filled power equipment or equipment) filled with high-pressure insulating oil (hereinafter also referred to as insulating oil) such as an oil breaker or oil-filled transformer. Used. The insulating oil filled in the oil-filled power device is circulated using an insulating oil pipe (hereinafter also simply referred to as a pipe) for cooling and electrical insulation of the equipment.

  In general, a pipe flange fastened with a bolt and nut is used to connect the two insulating oil pipes. At this time, in order to prevent oil leakage from the flange portion, a gasket such as NBR (nitrile rubber) is interposed between the contact surfaces of the two pipe flanges. However, the gasket may be deteriorated due to heat generation of the device, temperature fluctuations ranging from −20 ° C. to + 30 ° C. in the device installation environment, and oil leakage may occur from the flange portion. Here, the flange portion is a concept including a bolt nut that fastens two pipe flanges that are in contact with each other.

  Of course, oil leakage can be stopped by replacing the deteriorated gasket with a new one. However, since it is necessary to remove the pipes once to replace the gasket, the power equipment must be stopped during the replacement work. Therefore, conventionally, there has been proposed a technique for stopping oil leakage from the flange portion while the device is in operation (see, for example, Patent Documents 1 and 2).

  Patent Document 1 discloses a technique in which the entire flange portion where oil leakage occurs is covered with a thin film several times, and a caulking agent is applied and cured from above the film to stop the oil leakage. . However, in the technique disclosed in Patent Document 1, since the flange portion is covered with the caulking agent together with the bolt and nut, the bolt and nut cannot be operated after the construction.

  In Patent Document 2, in order to stop oil leakage from the contact surfaces of the pipe flanges, an endless belt-like porous packing is wound around the contour line (contact line) of the contact surface exposed on the side surface of the flange portion. Technology is disclosed. And while this porous packing absorbs oil and retains it inside, the whole flange part including a bolt nut is thickly covered with a filler together with the porous packing to prevent oil leakage.

  Hereinafter, the oil leakage prevention method (hereinafter also referred to as a conventional method) of Patent Document 2 will be briefly described with reference to FIGS. 7 and 8. FIGS. 7A and 7B are end views (in the following, also simply referred to as flange end views) in which the pipe flange is cut in the radial direction, which sequentially shows the process steps of the conventional method. FIG. 8A is a flange end view at a process stage subsequent to FIG. 7B, and FIG. 8B is a flange end view at a process stage subsequent to FIG. 8A.

  First, with reference to FIG. 7 (A), the structure of the pipe flange of the flange part 100 and the oil leakage resulting therefrom will be briefly described.

First, the directions used in the following description are defined. In a direction parallel to the central axis of the pipe 102 ₁ and 102 _2, the direction of flow through the pipe insulating oil Oil, referred to as the axial direction Ax1. From the axial direction Ax1, it refers to a direction toward the outer side in the radial direction of the pipe 102 ₁ and 102 ₂ and radially Ax2. Further, a direction along the outer circumference of the pipe 102 ₁ and 102 _2, referred to the direction of advancing the right screw axially Ax1 the circumferential Ax3. Hereinafter, the pipes 102 ₁ and 102 ₂ may be simply referred to as the pipe 102.

The pipe flanges 102 ₁ F and 102 ₂ F are annular parallel plates formed integrally at the ends of the pipes 102 ₁ and 102 _{2 through} which the insulating oil Oil flows. The pipes 102 ₁ and 102 ₂ are fastened in a liquid-tight manner using pipe flanges 102 ₁ F and 102 ₂ F. “Liquid-tight” indicates a state in which fluid does not leak from the gap between the pipe flanges 102 ₁ F and 102 ₂ F. Hereinafter, the pipe flanges 102 ₁ F and 102 ₂ F may be simply referred to as a pipe flange 102F.

Both pipe flanges 102 ₁ F and 102 ₂ F include end faces 102 ₁ S and 102 ₂ S, which are annular planes, and cylindrical side faces 102 ₁ A and 102 ₂ A, respectively.

The opposing end faces 102 ₁ S and 102 ₂ S of both pipe flanges 102 ₁ F and 102 ₂ F are in close contact with each other. In this state, both pipe flanges 102 ₁ F and 102 ₂ F are fastened by a plurality of bolts and nuts (not shown) provided in the circumferential direction Ax3. Hereinafter, the surface where the end surfaces 102 ₁ S and 102 ₂ S are in close contact with each other is also simply referred to as a contact surface 102S. The contact surface 102S is provided with, for example, an NBR gasket 108 in order to prevent leakage of the insulating oil Oil.

Further, by fastening both pipe flanges 102 ₁ F and 102 ₂ F, both side faces 102 ₁ A and 102 ₂ A constitute a single cylindrical side face 102A. The side surface 102A is divided into side surfaces 102 ₁ A and 102 ₂ A with a contact line 102C, which is an outer contour line of the contact surface 102S, as a boundary.

  As described above, when the gasket 108 is deteriorated, as shown by the arrow Lk, oil leakage occurs along the contact surface 102S. Hereinafter, this oil leakage is also referred to as oil leakage Lk. The oil leakage Lk travels on the contact surface 102S in the radial direction Ax2, and eventually leaks from the contact line 102C to the outside. The oil leakage Lk1 is a capillary phenomenon caused by the pressure generated by the weight of the insulating oil Oil, the pressure applied to the insulating oil Oil in order to circulate the pipe 102 (hereinafter also referred to as operating pressure), and the gap between the contact surfaces 102S. It is caused by.

As shown in FIG. 7A, in the conventional method, first, the filler 114a is formed in a so-called dam shape with the side surface 102A exposed on both sides of the pipe flange 102F. Since this filler 114a has no oil surface adhesiveness, it cannot be directly adhered to the side surface 102A in a state where oil leakage has occurred. Therefore, in the conventional method, by bonding firmly filler 114a to healthy peripheral surface of the pipe 102 ₁ and 102 ₂ that oil is not attached, utilize this portion so to speak as a "base". Here, “oil surface adhesiveness” indicates the ability to adhere to an adherend surface to which oil has adhered without peeling.

  Then, based on the foundations provided on both sides of the pipe flange 102F, the filler 114a is raised in a dam shape from the left and right sides toward the side surface 102A. If oil adheres to the surface of the filler 114a that does not have oil surface adhesiveness, the portion loses adhesive ability. That is, if oil adheres, adhesion between the fillers 114a and adhesion to the side surface 102A cannot be performed, and a leakage path (oil passage) is formed. Therefore, it is necessary to swell the filler 114a while wiping and degreasing the leaked oil Lk1 that continues to leak from the contact line 102C. As the filler 114a, a material (curing time: 20 to 30 minutes) in which an epoxy vinyl ester resin adhesive is mixed with cinnabar is used.

  Subsequently, as shown in FIG. 7B, the porous packing 110 having oil absorbability is attached to the side surface 102A from which the oil leakage Lk1 has been wiped off, covering the contact line 102C. As a result, the oil leakage Lk1 is absorbed into the porous packing 110 (indicated by a region 112 in the figure), so that new adhesion of oil to the side surface 102A that is the construction surface of the filler 114a is suppressed.

  Subsequently, as shown in FIG. 8A, while the porous packing 110 absorbs the oil leak Lk1 and prevents leakage to the side surface 102A, the inside of the above-mentioned “dam” together with the porous packing 110, Filled with the filled filler 114b. Here, a boundary surface between the filler 114a formed in a dam shape first and the filler 114b added later is defined as 114c. Note that the same material as 114a is used for the filler 114b. Hereinafter, the fillers 114a and 114b may be simply referred to as “filler 114”.

  The cured filler 114 becomes a hard solid and cannot be cured by adding a new filler 114 to the surface thereof. That is, the filler 114 does not have the ability to add. Here, the addition ability is the ability to adhere the old and new fillers 114 when the uncured filler 114 is newly applied to the surface of the cured filler 114. Therefore, the filling operation of the filler 114b into the dam needs to be completed within the curing time of the filler 114a.

  Finally, as shown in FIG. 8B, a hard coating layer 116 is formed outside the filler 114 covering the pipe flange 102F. Here, the coating layer 116 is obtained by alternately laminating a resin adhesive and glass wool.

JP 2011-24901 A JP 2006-64166 A

  As described above, in the technique disclosed in Patent Document 2, in order to prevent oil leakage through the filler 114 before curing, the amount of leakage oil that can be retained inside until the filler 114 is completely cured is retained. The porous packing 110 is required. Therefore, depending on the amount of oil leakage, a large amount of porous packing 110 is required.

Moreover, since it is necessary to applying a filler 114 on the entire flange portion 100 including tubing 102 ₁ and 102 ₂ ambient, treated region becomes large, sufficient installation and working space is required. Furthermore, the flange part 100 hardened with the filler 114 may be enlarged in a rugby ball shape, and may interfere with other members such as a nearby flange part.

  Moreover, in this technique, since it is necessary to coat the entire flange portion 100 with the filler 114 within the curing time (20 to 30 minutes), it is actually applicable only to a small flange having a diameter of up to about 12 cm. . In other words, it is not possible to finish the construction of the top cover flange of the transformer used for the transformer equipment and the flange of a large special shape such as the radiator switching valve within the curing time (20 to 30 minutes) of the filler 114. It is extremely difficult. Further, in the technique disclosed in Patent Document 2, since the entire flange portion is thickly covered with the filler 114, the bolt and nut cannot be operated after the construction as in the technique of Patent Document 1.

  The present invention has been made under such a technical background. Accordingly, an object of the present invention is to provide a liquid leakage prevention method suitable for oil leakage prevention from a flange portion of a pipe used for electric power equipment. In particular, an object of the present invention is to provide a liquid leakage prevention method suitable for preventing oil leakage from an annular contact line that is a boundary that divides two pipe flanges joined at a contact surface.

  As a result of intensive studies, the inventor covered the oil leakage location with a material that increases the leakage area, dispersed and reduced the leakage pressure of the liquid leakage, and then applied the sealant and cured to prevent the liquid leakage. I came up with it. Therefore, the liquid leakage prevention method of the present invention includes the following first and second steps. In the first step, the liquid leakage prevention portion is covered with a thread material. In the subsequent second step, a blocking target region, which is a region including a liquid leakage blocking portion covered with the thread material, is liquid-tightly sealed with a sealing material.

  Here, the “thread-like material” is a long continuous line of fibers, and absorbs the leaked liquid due to the liquid absorbency of the fibers themselves and the capillary phenomenon caused by the gaps between the fibers. It is a material provided. As the thread-like material, for example, a thread, a string, a rope and a rope, a rope, or the like can be used in order of increasing diameter. In addition, “fiber” constituting the thread-like material is a thread-like substance finer than the thread, which is a natural fiber containing plant fibers such as cotton and hemp and animal fibers such as animal hair, and artificially produced. Includes both chemical fibers.

Further, the “liquid leakage prevention portion” includes both of the following (1) and (2) in which the state of liquid leakage is different.
(1) Location where liquid leakage has already occurred (hereinafter also referred to as “liquid leakage location”)
(2) Although no liquid leak has occurred, experience has shown that a liquid leak is likely to occur (hereinafter also referred to as a “liquid leak candidate location”).

  In the liquid leakage prevention method of the present invention, the leakage pressure is dispersed by covering the liquid leakage portion with a thread material. Therefore, the liquid leakage can be temporarily stopped over a sufficiently long period of time by covering the liquid leakage portion with the filamentous material with the primary sealing material having a short curing time. As a result, it is possible to easily prevent the liquid leakage during the temporary fixing, for example, by applying a final sealing material having a long curing time but a high liquid leakage preventing ability. Therefore, the present invention is suitable for prevention of oil leakage from a flange portion used in electric power equipment, particularly oil leakage from an annular contact line that is a boundary between two pipe flanges.

It is a schematic diagram with which it uses for description of the oil leak from the flange part which the liquid leak prevention method (henceforth an invention method only) of this invention makes one application object. (A) is a schematic diagram showing the principle of preventing liquid leakage from the contact surface of the pipe flange using the conventional method, and (B) is liquid leakage from the contact surface of the tube flange using the inventive method. It is a schematic diagram which shows the principle of prevention. (A) And (B) is a flange end view which shows the process step of the invention method of a 1st embodiment in order. It is a flange end view which shows the process step of 1st Embodiment following FIG. 3 (B). (A) is a schematic diagram which shows the process step of the invention method of 2nd Embodiment, (B) is an end elevation along the AA line of (A). (A) is a schematic diagram showing the process steps of the second embodiment following FIG. 5 (B), and (B) is an end view showing the process steps following (A). (A) And (B) is a flange end view which shows the process step of a conventional method in order. (A) is a flange end view showing the process steps of the conventional method following FIG. 7 (B), and (B) is a flange end view showing the process steps following (A).

  Embodiments of the present invention will be described below with reference to the drawings. In each figure, the shape, size, and arrangement relationship of each component are schematically shown to the extent that the present invention can be understood. Moreover, although the preferable structural example of this invention is demonstrated below, the material of each component, a numerical condition, etc. are only a suitable example. Therefore, the present invention is not limited to the following embodiments. Moreover, in each figure, the same code | symbol is attached | subjected to a common component and the overlapping description may be abbreviate | omitted. In addition, reference numerals of components that have a clear correspondence with other drawings may be omitted.

(Summary of Invention)
<Application object of the inventive method>
First, with reference to FIG. 1, the liquid leakage used as the application object in the case of using an invention method for a flange part is demonstrated. FIG. 1 is a schematic diagram for explaining liquid leakage from a flange portion, and shows a pipe flange and a bolt and nut used for fastening.

  In the following description, oil leakage, that is, “oil leakage” will be described as an example, but the invention method is not limited to oil leakage, and various fluids such as water, aqueous solutions, organic solvents, etc. Applicable to liquid leakage. In the case of oil leakage, the above-mentioned “Liquid leakage prevention location” is “Oil leakage prevention location”, the above “Liquid leakage location” is “Oil leakage location”, and the “Liquid leakage candidate location” is “oil leakage They may also be referred to as “candidate locations”, respectively.

First, the structure of the flange part 100 generally used for piping for insulating oil will be briefly described, including bolts and nuts. As shown in FIG. 1, both pipe flanges 102 ₁ F and 102 ₂ F are fastened by bolts 122 and nuts 124. More specifically, a bolt hole 122h, which is a through hole extending in the axial direction Ax1, is formed in the pipe flange 102F at equal angular intervals along the circumferential direction Ax3. Both bolt flanges 102 ₁ F and 102 ₂ F, that is, both pipes 102 ₁ and 102 ₂ are fastened by inserting the bolt 122 into the bolt hole 122 h and tightening with the nut 124. In this example, flat washers 126 are provided between the head of the bolt 122 and the pipe flange 102 ₁ F, and between the nut 124 and the pipe flange 102 ₂ F, respectively. Further, a spring washer (not shown) is usually provided between the nut 124 and the flat washer 126 to prevent the nut 124 from loosening.

  The oil leakage Lk described above proceeds on the contact surface 102S in the radial direction Ax2, and eventually reaches the bolt hole 122h. The leaked oil Lk reaching the bolt hole 122h fills the bolt hole 122h and leaks out of the flange portion 100 through any gap that continues to the bolt hole 122h.

For example, the oil leakage Lk2 leaks from the contact surface between the bolt head and pipe flange 102 ₁ F and the flat washer 126. Further, the oil leakage Lk3 leaks from the contact surfaces of the nut 124 and the pipe flange 102 ₂ F and the flat washer 126. Further, the oil leakage Lk4 leaks from the gap between the shaft portion of the bolt 122 and the screw groove of the nut 124 through a small spiral gap where the screw thread of the bolt 122 and the screw groove of the nut 124 are screwed together. . Further, the oil leak Lk filled in the bolt hole 122h leaks from the contact line 102C as the oil leak Lk1 through the contact surface 102S outside the radial direction Ax2 from the bolt hole 122h.

  As described above, various oil leaks occur from the flange portion 100, and the application target of the present invention is the oil leak Lk1 from the contact surface 102S of the pipe flange 102F. Other oil leaks Lk2 to Lk4 may be blocked by a conventionally known method.

<Liquid leakage prevention principle (compared to conventional method)>
Next, with reference to FIG. 2, the principle of the liquid leakage prevention of the inventive method will be described. FIG. 2A is a schematic diagram showing the principle of preventing liquid leakage from the contact surface of the pipe flange using a conventional method. FIG. 2B is a schematic diagram showing the principle of preventing liquid leakage from the contact surface of the pipe flange using the inventive method. 2A and 2B, the bolt 122 and the nut 124 are not shown. 2 (A) and 2 (B) also show the pipe flange partially cut away.

  First, with reference to FIG. 2A, the principle of liquid leakage prevention by the conventional method will be described. In the conventional method, the contact line 102C is covered over the entire circumference with the porous packing 110 having the property of absorbing oil. By using a sufficient amount of the porous packing 110, the leaked oil Lk1 from the contact line 102C is absorbed into the porous packing 110 and remains inside the porous packing 110 as indicated by the arrow Ar1 and the region 112. .

  In the conventional method, while the porous packing 110 keeps the oil leakage Lk1 inside, the entire tube flange 102F is covered with the filler 114 together with the porous packing 110 (see dotted line in the figure). Thereby, the oil leakage Lk1 from the contact line 102C is prevented.

  Note that a large amount of porous packing 110 is required in the conventional method because when the oil oozes out from the packing 110, the side surface 102A and the surface of the filler 114a to which the oil adheres and the newly added filler 114b are added. It is because it does not adhere. As a result, an oil passage is formed on the boundary surface 114c between the fillers 114a and 114b that are not bonded, and oil leaks out of the flange portion 100. Therefore, in the conventional method, it is necessary to use an amount of the porous packing 110 that can reliably store the oil inside until the filler 114b is completely cured (see FIG. 8A).

  Next, with reference to FIG. 2B, the principle of preventing liquid leakage by the inventive method will be described.

  In the method of the invention, the contact line 102C, which is an oil leakage point, is covered with the thread-like material 12 over the entire circumference. When the contact line 102C is covered with the thread-like material 12, the oil leakage Lk1 from the contact line 102C spreads widely within the thread-like material 12 due to the capillary phenomenon derived from the fine gaps between the constituent fibers, and the thread-like material 12 is wide. From the surface, it soaks out so to speak (arrow Ar2 in the figure). That is, by covering the contact line 102C with the thread material 12, the leakage pressure of the oil leakage Lk1 can be greatly dispersed. Here, the “leakage pressure” corresponds to “momentum” in which leaked oil leaks from the oil leak location, and is the pressure of the oil leaking from the oil leak location converted into a unit area. In the method of the invention, the oil leakage area is covered with the thread material 12 to increase the area where the oil leaks, and the leakage pressure is dispersed and reduced over this large area.

Thus, it is necessary to disperse the leak pressure because the leak pressure of about 0.09 kg / cm ² per 1 m of the drop is applied to the leak location due to the dead weight of the insulating oil Oil. Therefore, even if the oil leaks from a small pinhole, the leakage pressure derived from the weight of the insulating oil and the capillary phenomenon is concentrated at this one point. A road will be formed.

  On the other hand, in the present invention, after the leakage pressure concentrated on the pinpoint is dispersed, the side surface 102A is covered with the thread material 12 and the sealing material 14 having the oil surface adhesiveness to prevent oil leakage (FIG. (See the middle dotted line). Specifically, since the leakage pressure is greatly dispersed by the weft thread wound around the side surface 102A, the sealing material 14 can be reliably cured even in a state where oil leakage continues. Thereby, the invention method can liquid-tightly seal the oil leakage prevention portion.

  On the other hand, in the conventional method, since the filler 114 does not have oil surface adhesiveness, it is difficult to apply the side surface 102A while oil leakage continues, and the porous packing 110 that does not leak a certain amount of absorbed oil to the outside. Is essential.

  Further, when the amount of oil leakage is large or the construction site is large, the oil oozes out from the porous packing 110 and spreads over the dam wall surface of the filler 114 and the entire side surface 102A. Even if a new filler 114 is added in this state, the filler 114 having no oil level adhesion does not adhere to these members, and an oil passage is formed. Therefore, in the conventional method, when the amount of oil leakage is large or when the construction location is large, the construction itself becomes extremely difficult.

  Further, since the filler 114 does not have the ability to add up, even if the uncured filler 114 is added over the cured filler 114, the two do not adhere to each other and are not integrated. For this reason, it is necessary to complete all operations within the curing time (20 to 30 minutes) of the filler 114.

  In this way, the conventional method is a method of sealing the flange portion 100 with a hard container composed of the filler 114 and the coating layer 116, storing the oil leakage inside, and confining the oil to the outside by confining it. is there. On the other hand, the present invention is completely different from the conventional method in that the contact line 102C is covered with the thread-like material 12 and the sealing material 14 and oil leakage is prevented by the flange contact surface 102S which is the oil leakage point in the first place.

(First embodiment)
Next, a first embodiment of the inventive method will be described with reference to FIGS. 3A and 3B are flange end views sequentially showing the process steps of the inventive method of the first embodiment. FIG. 4 is a flange end view showing the process steps of the first embodiment following FIG. 3 (B). In addition, illustration of a volt | bolt and a nut is abbreviate | omitted in FIG. 3 (A), (B) and FIG.

<Preparation>
In order to improve the adhesion of the sealing material 14 applied to the oil leakage location in the second step described later, first, the side surface 102A of the pipe flange 102F as a blocking target region is cleaned.

  More specifically, first, the coating film is removed using a grinder or a release agent to expose the metal on the side surface 102A. Next, the side surface 102A is wiped with a cloth soaked with an organic solvent such as acetone, and the oil on the exposed metal surface is removed and degreased.

<First step>
Subsequently, as shown in FIG. 3A, a first step of covering the leaked portion with the filamentous material is performed.

  More specifically, the octopus thread 16 is wound along the contact line 102C of the pipe flange 102F where the oil leakage Lk1 occurs as in FIG. As a result, the oil leak Lk1 is absorbed by the octopus yarn 16 and diffused over the surface of the octopus yarn 16 over a wide area, and oozes out from the surface as shown by the arrow Ar2, so that the leakage pressure is dispersed. Can do.

  In this example, the case where the thread-like material covering the oil leakage portion is the octopus yarn 16 which is a twisted yarn made of cotton is described. As described above, it is preferable that the thread-like material covering the oil leakage portion is a twisted yarn obtained by twisting several yarns. By using the twisted yarn, the fibers constituting the yarn are twisted, the gap between the fibers is narrowed, and a stronger capillary phenomenon occurs. Therefore, the oil absorption speed is increased, and the absorbed oil can be quickly diffused over a wide area of the yarn. Further, the filamentous material is preferably cotton. Since the material itself has oil absorbency, cotton can quickly absorb oil leakage and can quickly diffuse the absorbed oil over a wide range.

  The octopus yarn 16 is a yarn obtained by twisting three unit cotton yarns. Here, the unit cotton yarn is a yarn composed of a plurality of finer cotton yarns. By using the octopus thread 16, oil leakage can be absorbed and diffused quickly through a synergistic effect of a strong capillary phenomenon derived from the structure of the thread and a high oil absorbency derived from the material.

  In this example, the octopus yarn 16 is wound three times along the contact line 102C. This is to increase the surface area of the octopus yarn 16 and sufficiently disperse the leakage pressure of the oil leakage Lk1. Thus, the surface area of the octopus yarn 16 covering the oil leakage location may be determined in consideration of the oil leakage rate from the oil leakage location. Specifically, the area of the octopus yarn 16 is determined so that the leakage pressure of the oil leakage Lk1 is reduced to a value that does not inhibit the hardening of the primary sealing material 14a in the next step.

<Second step>
Subsequently, the second step will be described with reference to FIGS. In the second step, the blocking target region 18, which is a region including the contact line 102 </ b> C that is an oil leakage portion covered with the octopus thread 16, is sealed in a liquid-tight manner with the sealing material 14. Here, the blocking target region 18 is a portion of the side surface 102A of the pipe flange 102F including the contact line 102C that is an oil leakage point. More specifically, the second process includes a first sub process and a second sub process. In this example, the sealing material 14 includes a primary sealing material 14a used in the first sub process and a final sealing material 14b used in the second sub process, as will be described later.

  As shown in FIG. 3B, in the first sub-process performed first, the primary sealing material 14a is applied to a necessary partial region of the blocking target region 18 including the octopus yarn 16 and cured.

  The primary sealant 14a is preferably made of a material having a fast curing property and an oil surface adhesion that can complete the curing while preventing leakage of the oil leakage Ar2 that continues during the curing. The fast-curing primary sealing material 14a prevents oil leakage immediately after application in this way, so that it functions as a temporary stopper for oil leakage until the final sealing material 14b is completely cured.

  In order to complete the curing in the continued state of the oil leakage Ar2, the curing time of the primary sealing material 14a is preferably within 5 minutes. As such a sealing material, for example, “Leak Barrier” (trade name) of Toyokusho Leak Maintenance Co., Ltd., which can be cured in a minimum of 5 minutes by heating or the like is suitable.

  As shown in FIG. 4, in the second sub-process to be performed next, the final sealing material 14b is applied to the region including the cured primary sealing material 14a and cured. More specifically, the final sealing material 14b is applied to the side surface 102A of the pipe flange 102F, which is the blocking target region 18, and cured. That is, after the primary sealing material 14a is cured, the final sealing material 14b is applied to the blocking target region 18 so as to completely cover the primary sealing material 14a. In this way, while the leaked oil is temporarily fixed with the hardened primary seal material 14a, the final seal material 14b is cured to completely prevent the oil leak from the contact line 102C that is the oil leak location. .

  The final seal material 14b that covers the primary seal material 14a that is cured under the continuation of the leaked oil Ar2 is required to have oil surface adhesiveness as with the primary seal material 14a. Moreover, sufficient weather resistance is calculated | required by the last sealing material 14b exposed directly to the external environment. In particular, the final sealing material 14b is required to be flexible enough to cope with expansion and contraction along the axial direction Ax1 of the pipe 102, which is a base material generated due to temperature fluctuations in the installation environment. More specifically, it is preferable that the final sealing material 14b can cope with expansion / contraction of about 0.5 mm / 1 m of the metal pipe 102 caused by the temperature fluctuation of about 50 ° C. That is, a material that can follow the interval variation of the same amount as the above-described expansion and contraction generated in the gap between the contact surfaces 102S of the pipe flange 102F is preferable. As such a material, for example, urethane rubber or the like is suitable. Specifically, as the final sealing material 14b, for example, US An Illinois Tool Works Inc. “Devcon Flexane 80P” (trade name) and the like are suitable. The Devcon Flexane 80P is provided with a flexibility that can follow the variation in the interval between the contact surfaces 102S of the pipe flange 102F described above in the range of −30 ° C. to 80 ° C. Specifically, since Devcon Flexane 80P has an elongation rate of 300% or more and a tensile strength of 12 MPa or more, it can sufficiently cope with the above-described interval variation and the tensile force generated therefrom.

  Thus, by using a material that is more flexible than the primary seal material 14a for the final seal material 14b, cracks or the like occur in the internal primary seal material 14a due to temperature changes or the like. The oil is blocked by the final sealing material 14b having a high elongation rate and tensile strength, and oil leakage is prevented.

(effect)
Next, the effects of the liquid leakage prevention method of the present invention will be described.

  (1) In the liquid leakage prevention method of the present invention, since the sealing material 14 is applied only to the side surface 102A of the pipe flange 102F, the bolt and nut of the flange portion 100 can be operated even after the completion of construction. As a result, in the present invention, the pipe 102 can be disassembled only by operating the bolts and nuts, and the pipe 102 after disassembly can be reused.

In contrast, in the conventional method, as described above, it can not operate the bolt and nut of the tube flange 102F after construction, when dismantled, it is necessary to cut both pipes 102 ₁ and 102 _2, labor intensive. Further, the cut pipe 102 that cannot be reused must be discarded. As described above, the conventional method has more restrictions on the handling of the pipe 102 than the present invention.

  (2) In the liquid leakage prevention method of the present invention, it is only necessary to apply the sealing material 14 to the minimum necessary area. Therefore, compared with the conventional method which coat | covers the whole pipe flange 102F with the thick filler 114, the size of the flange part 100 after construction can be made small. As a result, the liquid leakage prevention method of the present invention can be applied to a case where the construction space and work space are restricted, or to oil leakage from the flange portion 100 adjacent to other members.

  (3) Further, the sealing material 14 required for oil leakage prevention by the liquid leakage prevention method of the present invention is smaller than the filler 114 of the conventional method. Therefore, the liquid leakage prevention method of the present invention can be applied more easily and in a shorter time than the conventional method. That is, the sealing material 14 of the liquid leakage prevention method of the present invention requires a small amount, has a narrow construction range, and has a fast curing time. Therefore, curing can be promoted by keeping it at a desired temperature. For example, even in a temperature environment of −20 ° C., curing is completed in a practically short time by applying warm air with a dryer or winding an electrothermal heat insulating mat. Therefore, the liquid leakage prevention method of the present invention can prevent oil leakage even under severe environments.

  On the other hand, the filler 114 of the conventional method requires a large amount and a large construction range, and requires 20 to 30 minutes to cure even at room temperature. Therefore, in the above-mentioned temperature environment, it is difficult to keep the applied filler 114 as a whole at or above the suitable temperature for curing, and the time required for curing is greatly extended. Therefore, there is a high possibility that oil will overflow from the porous packing 110 before the filler 114 is sufficiently cured. If the surface of the filler 114 and the side surface 102A that have already been applied are contaminated by the overflowed oil, the filler 114 having no oil surface adhesiveness cannot adhere to these members, making it difficult to prevent oil leakage. Become.

  (4) In the liquid leakage prevention method of the present invention, a thread material is used to cover the liquid leakage portion. As the thread-like material, yarns, strings, ropes, ropes, ropes, and various diameters can be used alone or in combination. Since the filamentous material can be freely selected in thickness and can be freely bent and deformed, the leakage pressure can be dispersed by using it in a liquid leakage portion having a complicated shape.

  In addition, the octopus yarn 16 used in the embodiment can be selected in various thicknesses between 0.5 and 5.5 mm in diameter. Therefore, the liquid leakage prevention method of the present invention can also be applied to oil leakage from the contact surface 102S of the pipe flange having the minimum thickness (9 mm) according to JIS standards.

  On the other hand, the porous packing 110 used in the conventional method has a standard, has a low degree of freedom in shape change, and returns to its original shape even when it is deformed. Therefore, the porous packing 110 cannot cope with liquid leakage from a flange having a non-standard shape.

  (5) In the liquid leakage prevention method of the present invention, if the primary sealing material 14a having a curing time of 5 minutes or less is used, the oil leakage can be quickly prevented against the leakage pressure even in a state where the oil leakage continues. As a result, it is possible to ensure the time until the final sealing material 14b to be cured next is cured. In addition, since the oil leakage is temporarily fixed by the primary sealing material 14a, a sufficient time can be taken for the construction of the final sealing material 14b. As a result, the final sealing material 14b having a uniform and sufficient thickness can be provided on the primary sealing material 14a, and oil leakage can be prevented over a long period of time.

(Second Embodiment)
Next, a second embodiment of the inventive method will be described with reference to FIGS. FIG. 5 (A) is a schematic diagram showing process steps of the inventive method, and FIG. 5 (B) is an end view taken along line AA of FIG. 5 (A). 6A is an end view showing a process step following FIG. 5B, and FIG. 6B is an end view showing a process step following FIG. 6A.

  Since the oil leakage location is the pinhole 20, the second embodiment is the same as the first embodiment except that the mode of the filamentous material covering the oil leakage location in the first step is different. Accordingly, the following description may be omitted.

<First step>
With reference to FIG. 5 (A) and (B), the 1st process of 2nd Embodiment is demonstrated. Prior to the first step, as in the first embodiment, a preparatory work for exposing the bare metal in the blocking target region and performing degreasing is performed. As shown in FIG. 5A, in the second embodiment, oil leakage Ar3 is generated from the pinhole 20 generated in the wall surface 120a of the device 120. In this example, the oil leakage Ar3 is in the form of oil droplets that drop intermittently. In this embodiment, as a thread material covering the pinhole 20, a thread forming sheet 22 in which an octopus thread 16 is spirally wound and formed into a disk shape is used.

  As shown in FIG. 5 (B), in the first step, the yarn forming sheet 22 is attached so as to cover the pinhole 20 with a known adhesive. As a result, the oil leakage Ar3 from the pinhole 20 is quickly diffused over a wide range to the yarn forming sheet 22 due to the properties of the octopus yarn 16 described above, and oozes out from the wide range of the surface of the sheet 22 with the wrinkles. Leaks out (arrow Ar4 in the figure). That is, by using the yarn forming sheet 22, the leakage area of the oil leakage Ar3 can be greatly increased. As a result, the leakage pressure, which is the pressure per unit area when the leakage oil Ar3 leaks, can be greatly dispersed and reduced.

  In this example, the case where the yarn forming sheet 22 has a planar disk shape has been described. However, the yarn forming sheet 22 can have various shapes such as a square shape, an elliptical shape, and a woven shape in accordance with the shape of the oil leakage portion.

  In addition, the yarn forming sheet 22 made of the octopus yarn 16 has a high degree of freedom of shape deformation such as bending or twisting, and therefore can cope with oil leakage from, for example, a corner of a device or a curved surface.

  Furthermore, the size of the yarn forming sheet 22 and the thickness of the octopus yarn to be used can be arbitrarily selected in consideration of the amount of oil leakage from the oil leakage location. For example, even when the oil leakage speed at which oil is ejected from the pinhole 20 is large, the sealing material 14 can be cured with the leakage pressure by increasing the thickness of the yarn forming sheet 22 or increasing the area. It can be sufficiently reduced to a practical level.

  Subsequently, as shown in FIGS. 6A and 6B, a second process of liquid-tightly sealing the blocking target region with the sealing material 14 is performed. In detail, the 1st subprocess which apply | coats the primary sealing material 14a to the oil-leakage prevention location which is an area | region containing the thread forming sheet | seat 22, and hardens it is performed. Subsequently, a second sub-process is performed in which the final sealing material 14b is applied and cured in a region including the application region of the primary sealing material 14a. Thereby, oil leakage from the pinhole 20 is prevented.

  Moreover, 2nd Embodiment is suitable for prevention of the oil leak from the pinhole which arose in the various apparatus components (For example, a radiator, a radiator valve, a bushing, etc.) using insulating oil.

  As described above with reference to the first and second embodiments, the liquid leakage prevention method of the present invention prevents oil leakage from the contact line of the flange portion used in the device and oil leakage from the pinhole of the device. Can be effectively blocked.

  In the first and second embodiments, the case where oil leakage generated in the device is prevented has been described. However, the present invention can also be applied to prevention of liquid leakage. For example, if the present invention is applied in advance to a place where the liquid leak is likely to occur (liquid leak candidate place) such as the contact line 102C of the pipe flange 102F where the life of the gasket 108 is approaching, the service life of the gasket 108 is preliminarily applied. The occurrence of liquid leakage can be prevented even if the value exceeds.

  In the first and second embodiments, the case where both the primary sealing material 14a and the final sealing material 14b are used in the second step has been described in preventing oil leakage. However, when the amount of oil leakage is extremely small, the oil leakage may be prevented only by the thread material 12 and the final seal material 14b. More specifically, in the first step, the oil leakage portion is covered with the thread-like material 12 in order to disperse the leakage pressure, and in the second step, the final sealing material 14b is applied thereon. When the amount of oil leakage is small, this can prevent oil leakage.

12 threadlike material 14 sealing material 14a 1 primary seal member 14b final sealant 16 kite string 18 blocking object region 20 pinhole 22 yarns molded sheet 100 flanges 102, 102 _1, 102 ₂ pipes _102A, 102 1 A, ₁₀₂ 2 A side 102F, 102 ₁ F, 102 ₂ F Pipe flange 102 ₁ S, 102 ₂ S End surface 102S Contact surface 102C Contact line 108 Gasket 110 Porous packing 112 Region 114 Filler 120 Equipment 120a Wall surface 122 Bolt 122h Bolt hole 124 Nut 126 Flat Washer

JP 2011-163400 A JP 2006-64166 A

Claims (11)

A first step of covering the liquid leakage prevention portion with a thread-like material;
A liquid leakage prevention method comprising: a second step of liquid-tightly sealing a blocking target region, which is a region including the liquid leakage blocking portion covered with the filamentous material, with a sealing material.   The liquid leakage prevention method according to claim 1, wherein the thread material is a twisted yarn.   The liquid leakage prevention method according to claim 1 or 2, wherein the filamentous material is made of cotton.   The liquid leakage prevention method according to claim 1, wherein the sealing material has oil surface adhesion. The sealing material comprises a primary sealing material and a final sealing material,
The second step includes
A first sub-process for applying and curing the primary sealing material on the blocking target area; and a second sub-process for applying and curing the final sealing material on the area including the cured primary sealing material. The liquid leakage prevention method according to claim 1, wherein the liquid leakage prevention method is performed.   The liquid leakage prevention method according to claim 5, wherein the curing time of the primary sealing material is within 5 minutes. The sealing material comprises a final sealing material;
The liquid leakage prevention method according to any one of claims 1 to 4, wherein, in the second step, the final sealing material is applied to the prevention target region and cured.   The liquid leakage prevention method according to any one of claims 5 to 7, wherein the final sealing material is a material capable of following expansion and contraction due to a temperature change of a base material to which the final sealing material is applied. .   The liquid leakage prevention portion is an annular contact line that is a boundary that separates two joined pipe flanges from each other, and in the first step, the annular contact line is covered with the corresponding tangent line. The liquid leakage prevention method according to any one of claims 1 to 8, wherein a thread-like material is wound.   The liquid leakage prevention portion is a pinhole, and in the first step, a yarn forming sheet formed of the thread-like material is attached to the pinhole. The method for preventing leakage of liquid according to 1.   Before the said 1st process, The process which exposes the metal in the said block | prevention object area | region and the process which degreases this exposed metal are performed as described in any one of Claims 1-10 characterized by the above-mentioned. The liquid leakage prevention method as described.