Shutdown-free temporary plugging method for low-pressure energy medium pipeline

Abstract

The invention discloses a shutdown-free temporary leaking stoppage method for a low-pressure energy medium pipeline, which belongs to the technical field of pipeline repair and comprises the following steps of: 1, coating an adhesive around a damaged part of the pipeline, and covering a metal net on the damaged and coated area; and 2, sealing adhesive tape is wound outside the pipeline and the metal net. The metal net is adhered to the outer wall of the pipeline through an adhesive, and a metal net transition structure is formed between the sealing adhesive tape and the pipeline. Through isolation of the metal net, the sealing adhesive tape is prevented from making direct contact with floating rust and burrs on the surface of the pipeline, a safe and stable sealing combination face is provided for the sealing adhesive tape, the polishing step is omitted, the pipeline leaking stoppage efficiency is improved, and the energy medium leakage exposure time is shortened. By means of the leaking stoppage method, the damaged pipeline can be rapidly repaired, the good sealing effect is achieved within a long time, and a pipeline system can be maintained without stopping.

Description

Technical Field

[0001] The present invention belongs to the technical field of pipeline repair, and specifically relates to a temporary plugging method for low-pressure energy medium pipelines without shutdown. Background Technique

[0002] Energy medium pipelines (such as gas, water, chemical liquid transportation pipelines, etc.), as key facilities in industrial production, are prone to be affected by factors such as corrosion, mechanical wear, and stress cracking during long-term operation, resulting in local thinning or even perforation and leakage of the pipe wall. Such leaks not only cause a large amount of waste of energy medium, but if they involve toxic, flammable, and explosive media such as gas, they will also trigger major safety accidents such as fires, explosions, and poisoning, seriously threatening the lives of personnel and the production environment. However, in a continuous production system, the pipeline system often cannot be immediately shut down for thorough repair, and there is an urgent need for a fast and reliable temporary repair technology to control leaks and gain time for subsequent planned maintenance.

[0003] At present, the temporary repair of pipeline leaks mainly uses the surface winding sealing method. The conventional operation process is as follows: First, the outer wall of the pipeline around the leak point is manually polished to remove the surface floating rust and oxide layer; then, an electrically insulating tape with sealing performance is wound to cover the leak area; finally, a high-strength structural tape is wound externally to enhance the overall compressive resistance. However, this method has significant defects in practical applications.

[0004] First of all, the process of polishing the floating rust takes a long time, and during this period, the leaked medium continues to leak out. For toxic media such as gas, operators are exposed to a high-risk environment and are prone to secondary accidents due to inhaling harmful gases or contacting open flames. If it is a liquid medium, the flowing of the leaked liquid will further scour the damaged edge, accelerating the corrosion expansion, and even causing the perforation area to expand before repair. The floating rust layer has a porous and loose structure, and there are a large number of micro-gaps between the bonding surface of the tape. If the polishing is not thorough, the burrs of the remaining floating rust are easy to pierce the electrically insulating tape, and the pores of the rust layer form a leakage channel for the medium, resulting in a significant decline in the sealing performance. In addition, the liquid medium penetrates to the interface between the tape and the pipe wall during the winding process, directly destroying the initial adhesion of the adhesive, making the tape unable to fit effectively. Summary of the Invention

[0005] The purpose of the present invention is to provide a temporary plugging method for low-pressure energy medium pipelines without shutdown to solve the problems mentioned in the above-mentioned prior art.

[0006] Provide a temporary plugging method for low-pressure energy medium pipelines without shutdown, including: Step 1: Coat an adhesive around the damaged part of the pipeline, and cover the damaged and coated area with a metal mesh; Step 2: Wind a sealing tape outside the pipeline and the metal mesh.

[0007] As a further embodiment of the present invention: The adhesive can be preliminarily cured within 3 minutes, the tensile strength after preliminary curing is above 2 MPa, and the waterproof grade is above IP55.

[0008] The adhesive has the ability of rapid curing, that is, the adhesive forms a certain tensile strength in a short time, enabling the metal mesh and the pipeline to have the ability of rapid bonding without falling off, reducing the bonding operation time, and reducing the exposure time of the energy medium leakage. At the same time, the adhesive has a certain waterproof performance in a short time, avoiding softening and falling off when the adhesive is exposed to the liquid medium, and ensuring the stability of the adhesive in the humid environment after preliminary curing.

[0009] The flow pressure of the low-pressure energy medium pipeline usually does not exceed 1.6 MPa, and the tensile strength after preliminary curing of the adhesive above 2 MPa meets the bonding force requirements of the metal mesh.

[0010] As a further embodiment of the present invention: The adhesive can be preliminarily cured within 1 minute, the tensile strength after preliminary curing is above 2 MPa, and the waterproof grade is above IP55.

[0011] By adding a crosslinking promoting component under conditional triggering to the adhesive, the curing time of the adhesive can be significantly improved. When plugging the leak of the pipeline of the gas medium (such as coal gas), the waterproof grade of the selected adhesive after preliminary curing can be relatively low, and the waterproof effect can be gradually improved during the subsequent curing time.

[0012] As a further embodiment of the present invention: The adhesive can be preliminarily cured within 3 minutes, the tensile strength after preliminary curing is above 2 MPa, and the waterproof grade is above IP67.

[0013] When plugging the leak of the pipeline of the liquid medium, the waterproof grade of the selected adhesive after preliminary curing needs to be relatively high to ensure the rainproof effect after the pipeline repair exposed to the external environment.

[0014] As a further embodiment of the present invention: The adhesive can be preliminarily cured within 1 minute, the tensile strength after preliminary curing is above 2 MPa, and the waterproof grade is above IP67.

[0015] By adding a crosslinking promoting component under conditional triggering to the adhesive, the curing time of the adhesive can be significantly improved. When plugging the leak of the pipeline of the liquid medium, the adhesive needs to have both the ability of rapid curing and strong waterproof performance to avoid the decline of the bonding performance and sealing performance of the adhesive in the humid environment.

[0016] As a further embodiment of the present invention: The adhesive is a photo-cured epoxy resin system.

[0017] Activating a cationic initiator by ultraviolet light (UV) to generate active cations, promoting ring-opening polymerization to form a cross-linked network, enabling the epoxy resin system to have the ability of rapid curing. The epoxy resin system has high strength and chemical corrosion resistance, and has higher tensile strength and waterproof grade after complete curing. It is suitable for pipeline plugging scenarios of media such as liquids, strong corrosives, or exposure to external humid environments.

[0018] As a further embodiment of the present invention: the adhesive is a photo-curable acrylate system.

[0019] Activating a free radical initiator by ultraviolet light (UV) to generate active free radicals, forming polymer chains through free radical polymerization, enabling the acrylate system to have the ability of rapid curing. The acrylate system has a faster curing speed, which can effectively reduce the risk of exposure of leakage media. It is suitable for pipeline plugging scenarios of media such as gases and toxic substances.

[0020] Both the epoxy resin system and the acrylate system have good fluidity when uncured, can penetrate the pores of the rust on the pipeline surface, and form a dense sealing layer.

[0021] Since the metal mesh has a porous structure, ultraviolet light can pass through the pores to irradiate the epoxy resin system or acrylate system on the lower surface of the metal mesh to trigger the curing of the adhesive, solving the condition restriction that photo-curable adhesives usually need to react and cure in a light-transmitting environment of a transparent layer.

[0022] As a further embodiment of the present invention: the adhesive is a thermally curable acrylate system.

[0023] As a further embodiment of the present invention: the elongation of the material used for the metal mesh is 15% - 45%. The elongation of the metal mesh material enables the metal mesh to have a large deformation ability. Since pipelines are mostly circular pipes, and the leakage areas are mostly at the bottom of the curved parts of the pipeline, the metal mesh has a certain plastic deformation ability when fitting with the elbow pipe, and can adapt to the pipeline shape to be paved and opened.

[0024] Specifically, first cover the metal mesh on the pipeline notch, and apply a uniform tensile force around the metal mesh to make the metal mesh radiate and fit around the notch as the center. When the thin-layer structure is coated on the curved surface, different from the common method of forming folds to deal with the redundant parts generated by the thin-layer structure, the present invention adapts to the curved surface by tensile deformation of the metal mesh. As the fitting progresses, the redundant parts accumulate and are gradually squeezed to the edge of the metal mesh. The greater the stretching rate of the structure closer to the edge of the metal mesh, and finally the edge of the metal mesh can be cut off. And because the stress in the central part of the metal mesh is weak, this part still maintains a dense mesh covering the pipeline notch, maintaining the blocking effect of the metal mesh.

[0025] Through this bonding method of the present invention, no redundant wrinkles will occur on the metal mesh, thereby avoiding the generation of pores due to the lack of bonding area between the sealing tape and the wrinkles during winding. The metal mesh has a large plastic deformation ability at this elongation rate, reducing the springback effect after the deformation of the metal mesh, enabling the adhesive to overcome the resilience of the metal mesh and maintain the bonding shape of the metal mesh during the initial curing stage.

[0026] As a further embodiment of the present invention: the elongation rate of the material used for the metal mesh is 20% - 40%.

[0027] As a further embodiment of the present invention: the elongation rate of the material used for the metal mesh is 30% - 40%.

[0028] As a further embodiment of the present invention: the yield strength of the material used for the metal mesh is ≤250 MPa.

[0029] At this yield strength, it is ensured that the metal mesh preferentially undergoes plastic deformation under external force and can be easily laid flat on the arc surface of the pipeline, avoiding the debonding of the metal mesh and the adhesive due to material springback. After the metal mesh is laid out, the sealing tape can be evenly wound around the periphery of the pipeline without encountering mutation areas that affect the sealing effect.

[0030] As a further embodiment of the present invention: the yield strength of the material used for the metal mesh is ≤235 MPa.

[0031] As a further embodiment of the present invention: the yield strength of the material used for the metal mesh is ≤215 MPa.

[0032] As a further embodiment of the present invention: the yield strength of the material used for the metal mesh is ≤195 MPa.

[0033] As a further embodiment of the present invention: the mesh number of the metal mesh is 10 - 30 meshes. A finer mesh can increase the resistance and flow rate when the medium passes through, and ensure that the strength is not broken during the extension of the metal mesh. Therefore, the mesh number is limited to more than 10 meshes. However, the mesh aperture needs to meet the transmission of ultraviolet light during the photocuring of the adhesive, so the mesh number is limited to less than 30 meshes.

[0034] As a further embodiment of the present invention: the diameter of the metal wire for weaving the metal mesh is 0.5 mm - 2 mm. The diameter of the metal wire directly affects the flexibility and strength of the metal mesh. Fine wires have good flexibility but low strength, and excessive extension may cause the metal mesh to break, affecting the repair effect. Thick wires have high strength but large rigidity and are not easily deformed. Therefore, it is necessary to select a suitable metal wire diameter according to the pipeline diameter and the size of the pipeline break.

[0035] As a further embodiment of the present invention: after the metal mesh is combined with the adhesive layer, the coating thickness of the adhesive is less than the thickness of the metal mesh.

[0036] This setting avoids the adhesive extruding from the mesh holes of the metal mesh and contacting the sealing tape after the metal mesh is combined with the adhesive, ensuring that the metal mesh is partially embedded in the adhesive layer but not completely covered, forming an integral airtight "adhesive-metal mesh-sealing tape" sandwich structure. If the adhesive partially extrudes from the mesh holes and forms a certain strength after preliminary curing, when the sealing tape is wound around the outside of the metal mesh, it cannot press down the adhesive, which may cause gaps between the metal mesh and the sealing tape layer, resulting in stress concentration in this part and affecting the sealing effect.

[0037] As a further embodiment of the present invention: the coating range of the adhesive is larger than the coverage range of the metal mesh.

[0038] The adhesive is extruded and raised at the edge of the metal mesh, forming a chamfered transition structure at the edge of the metal mesh, so that the sealing tape and the edge of the metal mesh have a smooth transition. When they come into contact, there will be no structural fault, avoiding stress concentration when liquid or gas penetrates into this vacant area and increasing the leakage risk.

[0039] As a further embodiment of the present invention: the adhesive is coated on the side wall of the damaged port of the pipeline. By forming a filling structure with the adhesive, a smooth transition is achieved between the metal mesh and the damaged port of the pipeline, avoiding stress concentration when liquid or gas penetrates into this vacant area. The generated shear effect causes the medium to gradually penetrate between the metal mesh and the pipeline, resulting in the separation of the metal mesh and the adhesive.

[0040] As a further embodiment of the present invention: after winding the sealing tape around the pipeline and the metal mesh in step two, a medical adhesive tape is wound around the outside of the sealing tape as a structural skeleton.

[0041] As a further embodiment of the present invention: after winding the medical adhesive tape around the outside of the sealing tape in step two, a transparent tape is wound around the outside of the medical adhesive tape for external waterproofing.

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The metal mesh is bonded to the outer wall of the pipeline through the adhesive, forming a metal mesh transition structure between the sealing tape and the pipeline. Through the isolation of the metal mesh, the sealing tape is prevented from directly contacting the surface rust and burrs of the pipeline, providing a safe and stable sealing joint surface for the sealing tape, omitting the grinding step, improving the pipeline leak repair efficiency, and reducing the exposure time of energy medium leakage. Through this leak repair method, rapid repair of damaged pipelines can be achieved, and good sealing effects can be maintained for a long time. The pipeline system can be repaired without shutdown.

[0043] 2. Fill the surface rust of the pipeline with adhesive to prevent the energy medium from invading through the porous and loose structure of the rust, and improve the sealing effect after plugging.

[0044] 3. The porous structure of the metal mesh has greater deformation ability compared to the dense structure, and can adapt to the curved surface structure of the elbow pipe for deformation, making the metal mesh fit more closely with the surface of the elbow pipe, and avoiding the appearance of folds that may lead to weak sealing areas.

[0045] 4. The mesh structure of the metal mesh can form a blocking structure after covering the damaged opening of the pipeline, and has a certain effect of delaying the flow of the medium. Especially when dealing with liquid media, the surface tension of the liquid requires a relatively large flow pressure when passing through the fine mesh holes. Detailed implementation manners

[0046] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be described and explained below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0047] In addition, it can also be understood that although the efforts made in this development process may be complex and lengthy, for those of ordinary skill in the art related to the content disclosed in the present application, some design, manufacturing or production changes based on the technical content disclosed in the present application are only conventional technical means and should not be understood as the content disclosed in the present application being insufficient.

[0048] However, there will be cases where unnecessary detailed descriptions are omitted. For example, there are cases where the detailed descriptions of well-known matters are omitted and the repeated descriptions of actually identical structures are omitted. This is to avoid the following descriptions from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the following descriptions are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter recited in the claims.

[0049] Embodiment 1

[0050] This embodiment is a temporary plugging method for a low-pressure water pipe. The diameter of the water pipe is 200 mm, the average water pressure of the water pipe is 0.6 MPa, the average width of the damaged crack is 2 mm, the length of the damaged crack is 30 mm, and the damaged part is in the 90° elbow pipe area.

[0051] The material of the metal mesh selected in this embodiment is 0Cr18Ni9 stainless steel, the diameter of the metal wire is 1.5 mm, and the mesh number of the metal mesh is 16 meshes.

[0052] The adhesive selected in this embodiment is the cationic photocurable epoxy resin of the MDH series from Hubei Maidehao Biotechnology Co., Ltd.

[0053] It includes the following steps: Step 1: Coat a layer of adhesive with a size of 70mm×70mm around the damaged part of the water pipe, and cover a layer of metal mesh with a size of 65mm×65mm on the damaged and coated area. The metal mesh fits well with the elbow part without wrinkles. Step 2: Use a mercury lamp with an intensity of 100mW / cm 2 to irradiate the adhesive area for 2 minutes, and the adhesive is preliminarily cured. Step 3: Wind electrical tape around the outside of the pipe and the metal mesh. When the water leakage stops, wind medical tape outside the electrical tape, and finally wind transparent tape outside the medical tape.

[0054] In this embodiment, the low-pressure water pipe is plugged in 8 minutes. After plugging, the low-pressure water pipe has no water droplet leakage within 48 hours, and there is no surface water seepage and dampness at the winding edge of the water pipe.

[0055] Comparative Example 1 This comparative example is a temporary plugging method for a low-pressure water pipe. The diameter of the water pipe is 200mm, the average water pressure for water conveyance in the pipe is 0.6MPa, the average width of the damaged crack is 2mm, the length of the damaged crack is 30mm, and the damaged part is a 90° elbow area.

[0056] It includes the following steps: Step 1: Do not treat the scum and rust on the periphery of the damaged opening of the pipe. Step 2: Wind electrical tape around the outside of the pipe. The winding method and number of winding layers of the electrical tape are the same as those in Example 1. When the water leakage stops, wind medical tape outside the electrical tape, and finally wind transparent tape outside the medical tape.

[0057] In this comparative example, after plugging, the low-pressure water pipe shows water seepage and dampness at the winding edge within 12 hours, and local water droplet leakage occurs within 24 hours.

[0058] Comparative Example 2 In this comparative example, the scum and rust on the surface of the low-pressure water pipe are polished with sandpaper. It takes 20 minutes to basically polish the scum and rust in the 50mm×50mm area on the surface of the water pipe, and the plugging time is greatly extended.

[0059] Example 2

[0060] This embodiment is a temporary plugging method for a low-pressure gas pipeline. The diameter of the gas pipeline is 500mm, the average gas pressure for gas conveyance in the pipeline is 50KPa, the average width of the damaged crack is 4mm, the length of the damaged crack is 50mm, and the damaged part is a straight pipe area.

[0061] In this embodiment, the material of the metal mesh is 0Cr18Ni9 stainless steel, the diameter of the metal wire is 0.8 mm, and the mesh number of the metal mesh is 25 meshes.

[0062] The adhesive selected in this embodiment is the photo-curing acrylate with the CAS number 109-16-0 produced by Hubei Huada Fine Chemical Co., Ltd.

[0063] It includes the following steps: Step 1: Coat a layer of adhesive with a size of 90 mm × 90 mm around the damaged part of the gas pipe. The adhesive is coated on the side wall of the pipe break. Cover a layer of metal mesh with a size of 85 mm × 85 mm on the damaged and coated area. The metal mesh fits well with the straight pipe part without wrinkles. Step 2: Use a mercury lamp with an intensity of 100 mW / cm 2 to irradiate the adhesive area for 30 s, and the adhesive is preliminarily cured. Step 3: Wind electrical tape around the pipe and the metal mesh. When the air leakage stops, wind medical tape around the electrical tape, and finally wind transparent tape around the medical tape.

[0064] In this embodiment, the low-pressure gas pipe is plugged within 5 minutes, and there is no gas leakage in the low-pressure gas pipe within 48 hours after plugging.

[0065] It should be noted that this application is not limited to the above embodiments. The above embodiments are only examples. Embodiments with the same structure in essence and the same function and effect within the technical solution scope of this application are included in the technical scope of this application. In addition, within the scope of not departing from the main idea of this application, various deformations that can be thought of by those skilled in the art on the embodiments, and other ways constructed by combining some constituent elements in the embodiments are also included in the scope of this application.

Claims

1. A temporary leak plugging method for low-pressure energy medium pipelines without shutdown, characterized in that, Including: Step 1: Apply an adhesive around the damaged part of the pipeline, and cover a metal mesh on the damaged and coated areas; Step 2: Wind a sealing tape outside the pipeline and the metal mesh.

2. A temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 1, characterized in that The adhesive can be preliminarily cured within 3 minutes, the tensile strength after preliminary curing is above 2 MPa, and the waterproof grade is above IP55.

3. A temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 2, characterized in that, The adhesive is a photo-cured epoxy resin system or a photo-cured acrylate system.

4. A temporary plugging method for low-pressure energy medium pipelines without shutdown according to claim 1, characterized in that, The elongation of the material used for the metal mesh is 15% - 45%.

5. The temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 1, characterized in that, The yield strength of the material used for the metal mesh is ≤250 MPa.

6. A temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 1, characterized in that, The mesh number of the metal mesh is 10 - 30 meshes.

7. A temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 1, characterized in that, The diameter of the metal wire for weaving the metal mesh is 0.5 mm - 2 mm.

8. A temporary plugging method for low-pressure energy medium pipelines without shutdown according to claim 7, characterized in that, After the metal mesh is combined with the adhesive layer, the coating thickness of the adhesive is less than the thickness of the metal mesh.

9. A temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 1, characterized in that, The coating range of the adhesive is larger than the coverage range of the metal mesh.

10. A temporary plugging method for a low-pressure energy medium pipeline without shutdown according to claim 1, characterized in that, The adhesive is coated on the side wall of the pipeline break.