JP5896956B2 - Gas leakage blockage method - Google Patents

Description

  The present invention relates to a gas leakage portion closing method for closing a gas leakage portion which is a gas leakage path from the inside of a gas pipe through which gas flows.

  The gas pipe through which the gas circulates is configured to include a flow pipe serving as a main flow path, and a threaded joint used at a connection point or a branch point of the flow pipe. If gas pipes and sealants such as flow pipes and threaded joints deteriorate or corrode due to aging, etc., thread threads on threaded joints or flow pipes may be lost or through holes may be formed in the flow pipes themselves. Gas may leak from the inside of the pipe to the outside.

  Therefore, as a technique for closing a gas leakage part, which is a gas leakage path such as a thread defect or a through-hole, after covering the gas leakage part with an uncured photo-curing resin, the covered part is made of a polyethylene transparent tape. A technique is disclosed in which the gas curable resin is cured by irradiating light from above the transparent tape to close the gas leakage portion (for example, Patent Document 1).

  In addition, an uncured photocurable resin is applied in advance to a transparent tape made of polyethylene, and after the gas leakage portion is coated on the coated surface, light is irradiated from above the transparent tape to cure the photocurable resin. A technique for closing a gas leakage portion is disclosed (for example, Patent Document 2).

JP 2012-37045 A JP 2013-2561 A

  However, by using the techniques of Patent Documents 1 and 2 above, when the thread missing portion is closed, the edge of the threaded joint and the outer wall of the flow pipe (hereinafter simply referred to as “the outer wall of the gas pipe”) and the photo-curing property. A void is formed between the resin and the resin. Specifically, polyethylene used as a transparent tape is too soft and does not have stretchability, so it is difficult to apply tension to the transparent tape. It cannot be pressed sufficiently against the opening. Therefore, the opening of the gas leakage part can be covered, but the photocurable resin does not reach the back of the gas leakage part, and a gap is formed between the outer wall of the gas pipe and the photocurable resin. Become.

  Even if the gap is formed, the gas leakage portion is sealed with the photo-curing resin, so that the gas does not leak out during normal operation. However, when the photocurable resin is exposed to a high temperature (for example, about 900 ° C.) atmosphere such as a fire, the photocurable resin expands and the density of the photocurable resin decreases. If it does so, it will become easy to produce a crack in photocurable resin, and there exists a possibility of causing a secondary disaster by gas leaking by this crack. Here, if there is a gap between the outer wall of the gas pipe and the photocurable resin, the photocurable resin expands toward both the gap and the outside of the gas pipe, so that the photocurable resin is cracked. Time (the fire resistance time of the photocurable resin) is shortened to about 10 minutes.

  Moreover, since polyethylene is too soft, even if the techniques of Patent Documents 1 and 2 are used, a through-hole generated in a low-pressure conduit (internal pressure of less than 2.5 kPa) that is a gas pipe distributed to a consumer is blocked. However, it is possible to close the through-hole formed in a conduit having a high internal pressure (internal pressure is about 16 kPa: called an intermediate pressure conduit) in a state where gas is circulated. I couldn't.

  Therefore, the present invention can improve the adhesion between the outer wall of the gas pipe and the uncured photocurable resin by devising the material of the tape that presses the uncured photocurable resin, It is possible to avoid a situation in which a gap is formed between the outer wall of the gas pipe and the photocurable resin, and it is possible to close the through hole formed in the intermediate pressure conduit in a state where the gas flows. The object is to provide a gas leakage blockage method.

In order to solve the above-described problems, the gas leakage portion closing method of the present invention closes a gas leakage portion, which is a gas leakage path from the inside of the gas pipe to the outside, formed in the gas pipe through which the gas flows. A method for closing a gas leakage portion, the step of covering the gas leakage portion from the outer wall of the gas pipe using an uncured photo-curing resin, and a light transmission tape made of polypropylene. A tape is wound around the gas pipe, and the uncured photocurable resin is pressed against the outer wall of the gas pipe so as to adhere to the gas pipe, and the uncured photocuring property is applied to the gas leakage portion by the pressing force. Embedding a resin, irradiating the uncured photocurable resin with light through the transmissive tape, curing the uncured photocurable resin, and removing the transmissive tape. Special To.

  In addition, after the covering step, a release tape having a peelability with respect to the photocurable resin and having a light transmission property is attached to the uncured photocurable resin covering the gas leakage portion. The step of embedding the uncured photocurable resin, and in the embedding step, the transmission tape presses the uncured photocurable resin against the outer wall with the release tape interposed therebetween. It is good also to make it stick.

  In the removing step, the peeling tape may be removed together with the transmissive tape.

  The release tape may be made of a softer material than the transmission tape.

  Moreover, the said peeling tape is good also as being comprised with the material whose peeling property with respect to the said photocurable resin is higher than the said transmission tape.

  In order to solve the above-mentioned problem, another gas leakage portion closing method of the present invention is a gas leakage portion which is formed in a gas piping through which a gas flows and which is a leakage route of the gas from the inside of the gas piping to the outside. A gas leakage portion closing method for closing a threaded portion of a threaded joint to be obtained, comprising a step of covering the threaded portion from an outer wall of the gas pipe using an uncured photocurable resin, and a polypropylene. A transparent tape, which is a tape having light permeability, is wound around the gas pipe so as to be in a direction opposite to the screwing direction of the screw joint, and the uncured photocurable resin is wound around the outer wall of the gas pipe. A process of embedding the uncured photocurable resin in the threaded portion by the pressing force and applying the pressing force, and irradiating the uncured photocurable resin with light through the transmission tape, The uncured photocurable tree Characterized in that it comprises a, and curing the.

  According to the present invention, by devising the material of the tape that presses the uncured photocurable resin, it is possible to improve the adhesion between the outer wall of the gas pipe and the uncured photocurable resin, It is possible to avoid a situation where a gap is formed between the outer wall of the gas pipe and the photocurable resin, and it is possible to close the through-hole formed in the intermediate pressure conduit with the gas flowing. It becomes.

It is a figure for demonstrating the conventional method which obstruct | occludes a gas leaking part using the transparent tape and photocurable resin made from polyethylene. It is a flowchart for demonstrating the flow of a process of the gas leak part obstruction | occlusion method concerning embodiment. It is a figure for demonstrating the flow of a process of the gas leak part obstruction | occlusion method concerning embodiment. It is a figure for demonstrating the flow of a process of the gas leak part obstruction | occlusion method concerning embodiment. It is a figure for demonstrating the flow of a process of the gas leak part obstruction | occlusion method concerning embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  FIG. 1 is a view for explaining a conventional method for closing a gas leakage portion 140 using a polyethylene transparent tape and a photocurable resin. FIG. FIG. 1B is a partially enlarged view of FIG. 1A, and FIG. 1C is an expansion of the photocurable resin 150. It is a figure for demonstrating a direction.

  As shown in FIG. 1 (a), the thread 112 of the flow pipe 110 and the thread 122 of the screw joint 120 that constitute the gas pipe 100 through which gas flows are deficient, and the flow pipe 110 and the screw joint 120 are screwed together. When gas leaks from the portion 130, that is, when the screwing portion 130 is the gas leakage portion 140 that is a gas leakage path from the inside of the gas pipe 100 to the outside, first, the gas leakage portion 140 is uncured photocured. (Hereinafter, referred to as “photocurable resin composition”). And after covering and covering the coating | coated location with the transparent tape made from polyethylene, light was irradiated from the transparent tape, the photocurable resin composition was hardened, and the gas leaking part 140 was obstruct | occluded.

  The polyethylene conventionally used to cover the photocurable resin composition is too soft and does not have stretchability (the elastic limit is too small), so it is wound around the gas pipe 100 (flow pipe 110, screw joint 120). It is difficult to apply tension to polyethylene when turning. Therefore, as shown in FIG. 1B, in polyethylene, the photocurable resin composition cannot be sufficiently pressed against the opening 140 a of the gas leaking part 140, and the photocurable resin composition is not contained in the gas leaking part 140. It does not reach the back. Then, although the opening 140a of the gas leakage part 140 can be covered, after the photocurable resin composition is cured (after irradiation with light), the photocurable resin 150 and the outer wall 114 of the flow pipe 110 are A gap S is formed between the photocurable resin 150 and the edge 124 of the screw joint 120.

  Even if such a gap S is formed, the gas leakage portion 140 is sealed with the photocurable resin 150 (see FIG. 1B), so that no gas leaks during normal operation. However, when the photocurable resin 150 is exposed to a high temperature (for example, about 900 ° C.) atmosphere such as a fire, the photocurable resin 150 is exposed to the voids S and the white arrows shown in FIG. Since the gas pipe 100 (the distribution pipe 110 and the threaded joint 120) expands outward both, the time until the photocurable resin 150 is cracked (the fire resistance time of the photocurable resin 150) is about 10 minutes. It will be shorter. If a crack occurs in the photocurable resin 150, gas may leak due to the crack and cause a secondary disaster. Therefore, it is desired to extend the fireproof time of the photocurable resin 150.

  Therefore, in the present embodiment, the adhesion between the outer wall 114 of the flow pipe 110 and the outer wall of the gas pipe 100 such as the edge 124 of the screw joint 120 and the photocurable resin composition is improved, and the outer wall of the gas pipe 100 is improved. A gas leakage portion closing method capable of avoiding a situation where the gap S is formed between the photocurable resin 150 and the photocurable resin 150 will be described.

(Gas leakage blockage method)
FIG. 2 is a flowchart for explaining the flow of processing of the gas leakage portion closing method according to the present embodiment. FIGS. 3, 4, and 5 are processes of the gas leakage portion closing method according to the present embodiment. FIG. 5A is a view for explaining the flow, FIG. 5A is a view for explaining the gas pipe 100 after closing, and FIG. 5B is a partially enlarged view of FIG. 5A. FIG. 5C is a view for explaining the expansion direction of the photocurable resin 150.

  As shown in FIG. 2, the gas leakage portion closing method includes a covering step S200, a forming step S210, an embedding step S220, an irradiation step S230, and a removing step S240. Hereinafter, each step will be described.

(Coating process S200)
As shown in FIG. 3A, the thread 112 of the flow pipe 110 and the thread 122 of the screw joint 120 are deficient, and the threaded portion 130 of the flow pipe 110 and the screw joint 120 is connected to the gas leakage part 140 (gas pipe). 3 (b), as shown in FIG. 3 (b), the outer wall of the gas pipe 100 (the outer wall 114 and the screw of the flow pipe 110) is formed using a photocurable resin composition 150a. Cover the gas leakage 140 at the edge 124) of the joint 120.

  In addition, in order to specify the position of the gas leakage part 140, since a complicated operation is separately required, from the viewpoint of improving work efficiency, here, the outer wall 114 of the flow pipe 110 and the edge 124 of the threaded joint 120 are separated. The space is covered with the photocurable resin composition 150a over the entire circumference. Hereinafter, the outer wall 114 of the flow pipe 110, the edge 124 of the screw joint 120, and the outer wall of the screw joint 120 are collectively referred to as “the outer wall of the gas pipe 100”.

  The photocurable resin composition 150a only needs to be cured by the energy of light (including visible light and ultraviolet light). Here, as the photocurable resin composition 150a, a resin composition that cures with light energy having a wavelength of 400 nm to 650 nm is used. For example, bisphenol A type epoxy acrylate 30 to 40 parts by mass, titanocene compound 1.0 to 2 A mixture of 0.0 part by mass and 37 to 48 parts by mass of filler is used.

  By using a photocurable resin composition 150a mainly composed of 30 to 40 parts by mass of bisphenol A type epoxy acrylate, gas leakage occurs in the photocurable resin 150 having water resistance and weather resistance and high mechanical strength. Portion 140 can be coated. Further, by containing 1.0 to 2.0 parts by mass of the titanocene compound as a photopolymerization initiator, the polymerization reaction can be started with light having a wavelength of visible light, and the curing rate can be improved. . Further, by containing 37 to 48 parts by mass of the filler, the fluidity of the photocurable resin composition 150a can be reduced, and the photocurable resin composition 150a is in close contact with the gas leakage part 140. It can be held.

  Moreover, it is obtained by curing a photocurable resin composition 150a composed of 30 to 40 parts by mass of a bisphenol A type epoxy acrylate, 1.0 to 2.0 parts by mass of a titanocene compound, and 37 to 48 parts by mass of a filler. In the photocurable resin 150, components sensitive to a gas detector such as an amine generated from a curing agent of an epoxy resin and alcohol hardly remain. Therefore, a gas leak test can be performed immediately after curing, and it can be quickly confirmed whether or not the gas leaking part 140 is closed.

(Molding step S210)
Subsequently, as shown in FIG. 3C, the release tape 160 is applied to the photocurable resin composition 150 a that covers the gas leakage part 140, and the photocurable resin composition 150 a is pressed from above the release tape 160. Etc., the photocurable resin composition 150a is molded. By performing the molding step S210, the gas leakage portion 140 can be uniformly coated with the photocurable resin composition 150a, and the bias of the photocurable resin composition 150a at the coating location can be reduced. Become.

  The release tape 160 is a tape that has at least peelability with respect to the cured photocurable resin 150 and light transmittance, and is made of, for example, polyethylene.

  Moreover, in this embodiment, the peeling tape 160 is comprised with a softer material than the transparent tape 170 mentioned later. Thereby, compared with the case where the photocurable resin composition 150a is coat | covered only with the transmissive tape 170, the shaping | molding of the photocurable resin composition 150a can be performed easily.

(Embedding step S220)
Subsequently, as shown in FIG. 3 (d), the transparent tape 170 is wound around the gas pipe 100 (the flow pipe 110 and the screw joint 120), and the photocurable resin composition 150 a is interposed with the release tape 160 interposed. Is pressed against the outer wall of the gas pipe 100 so as to be brought into close contact therewith, and the photocurable resin composition 150a is embedded in the gas leakage portion 140 by the pressing force.

  Here, the transmissive tape 170 is a light-transmitting tape made of polypropylene, and is, for example, a tape having a width of 40 mm to 50 mm and a thickness of about 0.15 mm to 2.0 mm. Polypropylene has high light transmittance and is stretchable (has a large elastic limit) compared to polyethylene. Therefore, when the transmissive tape 170 is made of polypropylene, the photocurable resin composition 150a can be pressed against the outer wall of the gas pipe 100 to be brought into close contact with the outer wall of the gas pipe 100 in a state where a tension larger than that of polyethylene is applied. In addition, the tension | tensile_strength applied to the permeable tape 170 is 90N-100N (the extent to which the 50 mm width transmissive tape 170 shrinks 10% (5 mm)), for example.

  Then, as shown in FIGS. 5A and 5B, it becomes possible to embed the photocurable resin composition 150 a deep into the gas leakage portion 140, and between the photocurable resin 150 and the gas pipe 100. A situation in which the gap S is formed can be avoided. Moreover, even if the space | gap S is formed, the space | gap S can be made small compared with the case where the photocurable resin composition 150a is pressed down with polyethylene.

  Therefore, even when the photocurable resin 150 is exposed to a high temperature (for example, about 900 ° C.) atmosphere such as a fire, as shown by the white arrow in FIG. Expands only to the outside of the gas pipe 100 (flow pipe 110, screw joint 120), so the time until the photocurable resin 150 is cracked (the fire resistance time of the photocurable resin 150) is extended to about 30 minutes. can do.

  In this embodiment, the transmission tape 170 is coated with an adhesive (for example, an acrylic adhesive), and the transmission tape 170 is attached to the gas pipe 100 with the adhesive adhered to the release tape 160. It will be wound.

  Further, in this embodiment, when the transmissive tape 170 is wound, it is wound in the same direction as the screwing direction of the screw joint 120 (generally, clockwise when the female screw side is viewed from the male screw side). turn. Thereby, it becomes possible to embed the photocurable resin composition 150a in the gas leakage part 140 efficiently.

(Irradiation process S230)
As shown to Fig.4 (a), in irradiation process S230, light is irradiated to the photocurable resin composition 150a through the peeling tape 160 and the permeation | transmission tape 170 using the light irradiation apparatus 180, and a photocurable resin composition is shown. The product 150a is cured to obtain a photocurable resin 150. Therefore, as described above, with the configuration in which the peeling tape 160 and the transmission tape 170 have light transmittance, in the irradiation step S230, light can efficiently reach the photocurable resin composition 150a, and the photocurable resin composition can be obtained. It is possible to suppress a decrease in the curing speed of the object 150a.

  Here, the light irradiation device 180 includes, for example, a light source that irradiates light of 400 nm to 650 nm, and has a light measurement amount of 150 lumens or more. With the configuration in which the light irradiation device 180 has a photometric quantity of 150 lumens or more, the curing rate of the photocurable resin composition 150a can be improved.

  Thus, by the structure which seals the gas leakage part 140 with the photocurable resin 150, while preventing the leakage of gas from the gas piping 100, the corrosion resistance of the gas piping 100 can be improved. In particular, when the gas pipe 100 is buried in the ground and there is a hot spring in the vicinity of the gas pipe 100, the gas pipe 100 may be corroded by sulfur compounds, alkalis, and acids derived from the hot spring. However, by sealing the gas leakage part 140 with the photocurable resin 150, corrosion of the gas pipe 100 can be suppressed.

(Removal step S240)
As described above, when pressing the photocurable resin composition 150a with the transmissive tape 170 in the embedding step S220, the release tape 160 is interposed between the transmissive tape 170 and the photocurable resin composition 150a. Therefore, as shown in FIG. 4B, in the removing step S240, the transmissive tape 170 is removed together with the peeling tape 160.

  Since the peeling tape 160 has peelability as described above, the transmissive tape 170 can be easily removed from the photocurable resin 150 together with the peeling tape 160 in the removing step S240.

  In the present embodiment, the release tape 160 is made of a material having a higher releasability with respect to the photocurable resin 150 than the transmission tape 170. Thereby, the transparent tape 170 can be easily removed as compared with the case where the photocurable resin composition 150a is covered only with the transparent tape 170.

  Further, as described above, since the adhesive is applied to the transmissive tape 170, in the removing step S 240, the peeling tape 160 can be removed while being adhered to the transmissive tape 170. The tape 170 can be easily removed from the photocurable resin 150.

  In this way, the photocurable resin composition 150a is cured by irradiating light through the peeling tape 160 and the transmission tape 170, and then the photocuring property after curing is removed. The surface of the resin 150 can be prepared by cutting, polishing, etc., and the coating performed thereafter can be performed satisfactorily.

  Further, since the peeling tape 160 and the transmissive tape 170 are made of plastic such as polyethylene or polypropylene, they are easily ignited when a fire occurs. Thus, the configuration that removes the peeling tape 160 and the transmission tape 170 can eliminate substances that cause ignition.

  As described above, according to the gas leakage portion closing method according to the present embodiment, the outer wall of the gas pipe 100 and the photocurable resin are formed by making the transmission tape 170 that presses the photocurable resin composition 150a made of polypropylene. Adhesiveness with the composition 150a can be improved. Thereby, it is possible to avoid a situation in which the gap S is formed between the outer wall of the gas pipe 100 and the photocurable resin 150. Therefore, the fireproof time of the photocurable resin 150 can be extended to about 30 minutes.

  In addition, according to the gas leakage portion closing method, the transparent tape 170 that presses the photocurable resin composition 150a is made of polypropylene, so that the photocurable resin composition 150a is applied in a state where a larger tension than polyethylene is applied. Can be brought into close contact with the outer wall of the gas pipe 100 by applying a pressing force. As a result, the conventional polyethylene transparent tape is formed into an intermediate pressure conduit (internal pressure is about 16 kPa), which is higher than the low pressure conduit (internal pressure is less than 2.5 kPa) that could not be blocked. It is possible to close the through-hole with the gas flowing therethrough.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above-described embodiment, the case where the release tape 160 is made of polyethylene has been described as an example. However, the release tape 160 has releasability with respect to the photocurable resin 150 and has light transmittance. If it is a thing, there is no limitation in a material. Moreover, if the peeling tape 160 can be easily peeled from the photocurable resin 150 (if it has peelability), the peelability may be worse than that of the transmission tape 170 (polypropylene). Furthermore, the release tape 160 may be harder than the transmission tape 170 (polypropylene) as long as the photocurable resin composition 150a can be easily molded.

  Moreover, in the said embodiment, although the resin composition hardened | cured with the energy of the light of the wavelength of 400 nm-650 nm was mentioned as an example and demonstrated as the photocurable resin composition 150a, light (including visible light and an ultraviolet-ray) is demonstrated. There are no limitations on the components as long as they are resin compositions that cure with energy. Therefore, the wavelength of the light irradiated by the light irradiation device 180 may be appropriately set according to the photocurable resin composition 150a.

  In addition, each process of the gas leakage part obstruction | occlusion method of this specification does not necessarily need to process in time series along the order described as a flowchart, and may include a parallel process.

  INDUSTRIAL APPLICABILITY The present invention can be used for a gas leakage portion closing method for closing a gas leakage portion that is a gas leakage path from the inside of a gas pipe through which gas flows.

S200 Coating step S210 Molding step S220 Embedding step S230 Irradiation step S240 Removal step 100 Gas pipe 120 Screw joint 130 Screwed portion 140 Gas leaking portion 150 Photocurable resin 150a Photocurable resin composition (Uncured photocurable resin) )
160 Release tape 170 Transmission tape

Claims (6)

A gas leakage portion closing method for closing a gas leakage portion, which is a gas leakage path from the inside of the gas piping to the outside, formed in a gas piping through which gas flows,
Using an uncured photocurable resin, covering the gas leakage part from the outer wall of the gas pipe;
A transparent tape, which is a light-transmitting tape made of polypropylene, is wound around the gas pipe, and the uncured photocurable resin is pressed against the outer wall of the gas pipe to bring it into close contact with the gas pipe. Embedding the uncured photocurable resin in the gas leakage part by pressure,
Irradiating the uncured photocurable resin with light through the transparent tape, and curing the uncured photocurable resin;
Removing the transmissive tape;
A gas leakage portion closing method comprising the steps of: After the coating step,
A release tape having releasability with respect to the photocurable resin and having a light transmission property is attached to the uncured photocurable resin covering the gas leakage portion, and the uncured photocurable resin is applied. Including the step of molding
In the embedding process, the transmission tape according to claim 1, characterized in that for adhering the uncured photocurable resin while interposing said release tape over a pressing force pressing said outer wall Gas leak blockage method. The gas leakage portion closing method according to claim 2 , wherein, in the removing step, the peeling tape is removed together with the permeable tape. The gas leakage portion closing method according to claim 2 or 3 , wherein the peeling tape is made of a softer material than the permeable tape. The release tape, the gas leak obstruction method according to any one of claims 2 to 4, characterized in that release property with respect to the photocurable resin from the transmission tape is composed of a material high.   A gas leakage portion closing method for closing a threaded portion of a screw joint that can be a gas leakage portion that is a gas leakage path from the inside of the gas piping to the outside formed in a gas piping through which gas flows,
  Using an uncured photocurable resin, covering the screwed portion from the outer wall of the gas pipe;
  A transmission tape, which is a light-transmitting tape made of polypropylene, is wound around the gas pipe so as to be in a direction opposite to the screwing direction of the threaded joint, and the uncured photocurable resin is supplied to the gas pipe. A process of pressing and pressing the outer wall of the pipe and applying a pressing force, and embedding the uncured photocurable resin in the threaded portion by the pressing force;
  Irradiating the uncured photocurable resin with light through the transparent tape, and curing the uncured photocurable resin;
A gas leakage portion closing method comprising the steps of:

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