An annular blocking airbag for trenchless repair or detection of pipeline defects without flow interruption

Abstract

The application provides an annular blocking air bag for pipeline defect non-shutoff trenchless repair or detection, which comprises an outer air bag fixedly installed around the outer wall of a center flow pipe, an inner air bag installed in the annular cavity of the outer air bag, and a flexible friction pad layer fixedly installed around the outer surface of the outer air bag; when the inner air bag is not inflated, the outer air bag is attached to the outer wall of the center flow pipe; after the inner air bag is inflated, the outer air bag is filled, so that the flexible friction pad layer is tightly abutted against the inner wall of the pipeline to be repaired; wherein the tensile modulus of the inner air bag is less than that of the outer air bag. In addition, a tensile membrane is further installed in the outer air bag, and the annular cavity is further divided into a volute cavity by the tensile membrane; a volute-shaped inner air bag is installed in the volute cavity. The application sets the inner and outer air bags with different deformation performances, so that the lateral expansion of the annular blocking air bag is weakened, the radial expansion is strengthened, the convenience of the trenchless repair or detection operation is improved, and the cost is low and the quality is controllable.

Description

Technical Field

[0001] This invention relates to the field of trenchless repair technology for underground pipelines, specifically to an annular blocking airbag for trenchless repair or detection of pipeline defects without interruption. Background Technology

[0002] As the years of use increase, underground drainage pipes are prone to varying degrees of damage, which can lead to sewage seepage that pollutes the surrounding environment, or external water (groundwater, river water, tap water leakage, etc.) seeping into and diluting the sewage in the pipes, resulting in problems such as increased sewage volume and low concentration. How to solve this pain point has become the focus of attention in the industry.

[0003] Chinese invention patent CN118391536B discloses a water-free, non-destructive repair device for pipeline defects, which uses an annular blocking airbag to block the upstream and downstream water flow of the pipeline, thereby creating a waterless repair space in the section of the pipeline to be repaired. However, in engineering practice, it has been found that ordinary airbag products have the following problems when inflated:

[0004] (1) The rubber airbag expands rapidly after inflation, but not in the ideal form of "complete radial expansion". Due to its own stress characteristics, the airbag installed on the central flow pipe will expand in a "donut" shape, that is, while expanding radially, the lateral expansion along the axial axis is more obvious. Although the radial expansion is quickly restricted by the pipeline to be repaired, the axial expansion of the airbag is obvious as the internal pressure of the airbag increases. If the distance between the adjacent equipment and the airbag is too small, the axial expansion of the airbag will seriously affect the normal use of its adjacent equipment (such as high-pressure flushing device); if the distance between the adjacent equipment and the airbag is too large, it will result in an excessively long repair device, which will increase the engineering cost.

[0005] (2) If the axial expansion of the airbag is weakened by adjusting the manufacturing process, the technical difficulty will increase, the manufacturing process will be more complicated, the manufacturing cycle will be longer, and the manufacturing cost will be higher.

[0006] Therefore, it is necessary to propose an annular blocking airbag for non-interceptive, trenchless repair or inspection of pipe defects that can effectively reduce axial expansion. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the present invention provides an annular blocking airbag for trenchless repair or detection of pipeline defects without interruption.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: An annular blocking airbag for trenchless repair or inspection of pipeline defects without interruption includes an annular outer airbag fixedly installed around the outer wall of a central flow pipe, an inner airbag installed inside the annular cavity of the outer airbag, and a flexible friction pad layer fixedly installed around the outer surface of the outer airbag. The outer airbag is also equipped with a tensile membrane, which further divides the annular cavity into a volute-shaped cavity; a volute-shaped inner airbag is installed inside the volute-shaped cavity. When the inner airbag is not inflated, the outer airbag is attached to the outer wall of the central flow tube. After the inner airbag is inflated, the outer airbag is filled, so that the flexible friction pad layer is tightly pressed against the inner wall of the pipe to be repaired. The tensile modulus of the inner airbag is smaller than that of the outer airbag.

[0009] Based on the above technical solution, the annular blocking airbag has a double-layer structure, with an inner airbag and an outer airbag. When the tensile modulus of the inner airbag is less than that of the outer airbag, the expansion deformation of the inner airbag after inflation is greater than that of the outer airbag. Therefore, the outer airbag will constrain the expansion deformation of the inner airbag, thereby constraining the lateral expansion deformation of the annular blocking airbag along the axis of the central flow pipe. The outer airbag adopts a size that matches the pipe to be repaired. Matching does not mean equal, but rather that it can fit tightly against the inner wall of the pipe to be repaired after expansion, so that the annular blocking airbag can generate sufficient expansion pressure on the pipe to be repaired. This allows the flexible friction pad layer to generate sufficient friction force to resist the internal water pressure of the pipe to be repaired.

[0010] As a preferred embodiment of the present invention, the external airbag includes an inner membrane fixedly installed around the outer wall of the central flow tube, two side membranes fixedly installed at both ends of the inner membrane, and an outer membrane fixedly connected to the two side membranes. The inner membrane, the outer membrane, and the two side membranes form an annular cavity that accommodates the internal airbag.

[0011] As a preferred embodiment of the present invention, the tensile modulus of the outer airbag is at least 1.2 times that of the tensile modulus of the inner airbag.

[0012] As a preferred embodiment of the present invention, the tensile strength of the outer airbag is not less than 12 MPa and the tensile modulus is greater than or equal to 0.24 GPa; the tensile strength of the inner airbag is not less than 10 MPa and the tensile modulus is less than or equal to 0.24 GPa, preferably less than or equal to 0.20 GPa.

[0013] As a preferred embodiment of the present invention, the external airbag is made of either canvas or rubber sheet.

[0014] As a preferred embodiment of the present invention, the internal airbag is made of either plastic or rubber. The plastic can be either PE (polyethylene) or PVC (polyvinyl chloride), and the rubber can be any of natural rubber, styrene-butadiene rubber, butadiene rubber, chloroprene rubber, nitrile rubber, hydrogenated nitrile rubber, or polyurethane rubber.

[0015] As a preferred embodiment of the present invention, the flexible friction pad layer is made of rubber tape, silicone tape or latex tape.

[0016] As a preferred embodiment of the present invention, the inner membrane is bonded to the outer wall of the central flow tube, and the flexible friction pad is bonded to the outer membrane; the inner membrane, the outer membrane, and the two side membranes are integrally connected or bonded.

[0017] As a preferred embodiment of the present invention, the tensile membrane is spirally arranged around the inner membrane, with the inner side fixedly connected to the inner membrane, the outer side fixedly connected to the outer membrane, and the two ends in the axial direction fixedly connected to two side membranes respectively.

[0018] Based on the above technical solution, when the inner airbag adopts a volute shape, its lateral expansion deformation is smaller than that of an annular airbag of the same diameter, further reducing the lateral expansion deformation of the annular obstruction airbag. The tensile membrane set inside the outer airbag can provide tension to the membranes on both sides of the outer airbag, further reducing the lateral expansion deformation of the annular obstruction airbag (that is, the expansion deformation along the central flow tube axis). At this time, the span between adjacent annular obstruction airbags after expansion is greatly reduced, the overall length of the device is effectively shortened, and the operation of components between adjacent annular obstruction airbags is more convenient. In addition, the tensile membrane can also constrain the deformation of the inner ring of the volute-shaped inner airbag, avoiding excessive deformation difference between the inner and outer rings (too large a difference is difficult to recover), making the overall deformation of the inner airbag more uniform, and ensuring the durability and service life of the inner airbag.

[0019] As a preferred embodiment of the present invention, the tensile modulus of the tensile membrane is greater than or equal to the tensile modulus of the external airbag.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects: (1) The inner and outer double membrane design is adopted. The inner airbag expands and the outer airbag can expand to a certain extent while restraining the expansion of the inner airbag. This weakens the axial expansion to a certain extent, shortens the equipment length, improves the convenience of operation, and at the same time ensures that there is sufficient radial expansion pressure. (2) To achieve true "radial expansion", the ingenious design of the annular choke-shaped tensile membrane of the circumferential choke airbag can effectively weaken the axial expansion of the annular choke airbag. (3) The cost is low. All the materials used are common and ordinary materials. In addition, the manufacturing process is simple and the quality control is easy, which gives the airbag a clear advantage in cost. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a ring-shaped occlusion airbag; Figure 2 This is a cross-sectional view of the annular chokehold airbag. Figure 3 Schematic diagram of the structure of an annular occlusion airbag Figure 1 (Without tensile membrane); Figure 4 Schematic diagram of the structure of an annular occlusion airbag Figure 2 (with tensile membrane); Figure 5 for Figure 1 A schematic diagram of part A in the middle; Figure 6 for Figure 1 A schematic diagram of part B in the middle; Figure 7 for Figure 2 A schematic diagram of part C in the middle; Figure 8 for Figure 2 A schematic diagram of part D in the middle; Figure 9 for Figure 2 A schematic diagram of part E in the middle; Figure 10 for Figure 3 A schematic diagram of a local part of F.

[0022] In the figure: 1- Annular blocking airbag; 11- Flexible friction pad; 12- Outer airbag; 121- Outer membrane; 122- Side membrane; 123- Inner membrane; 124- Tensile membrane; 13- Inner airbag; 14- Inlet and outlet ports; 2- Central flow pipe; 21- Flange. Detailed Implementation

[0023] The technical solution of the present invention will now be clearly and completely described in conjunction with the embodiments and accompanying drawings.

[0024] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] Example 1

[0026] Please see Figure 1-2 This embodiment provides an annular blocking airbag for trenchless repair or inspection of pipeline defects without interruption. It includes an annular outer airbag 12 fixedly mounted around the outer wall of a central flow pipe 2. An inner airbag 13 is installed inside the annular cavity of the outer airbag 12, and a flexible friction pad layer 11 is fixedly mounted around the outer surface of the outer airbag 12. When the inner airbag 13 is not inflated, the outer airbag 12 adheres to the outer wall of the central flow pipe 2. After the inner airbag 13 is inflated, the outer airbag 12 is filled, causing the flexible friction pad layer 11 to tightly abut against the inner wall of the pipeline to be repaired. The tensile modulus of the inner airbag 13 is less than that of the outer airbag 12. The annular shape of the outer airbag 12 is designed to match the annular gap between the central flow pipe 2 and the pipeline to be repaired as closely as possible.

[0027] It should be noted that in this embodiment, "inner" and "outer" refer to the pipe to be repaired or the central flow pipe 2. The closer to the central flow pipe 2, the inner side; and the closer to the pipe to be repaired, the outer side.

[0028] For details, please see Figure 3 , Figure 7 , Figure 9 , Figure 10 The external airbag 12 includes an inner membrane 123 that is fixedly installed around the outer wall of the central flow tube 2, two side membranes 122 that are fixedly installed at both ends of the inner membrane 123, and an outer membrane 121 that is fixedly connected to the two side membranes 122. The inner membrane 123, the outer membrane 121, and the two side membranes 122 form an annular cavity that accommodates the internal airbag 13.

[0029] Specifically, the tensile modulus of the outer airbag 12 is at least 1.2 times that of the inner airbag 13. The greater the difference in their tensile moduli, the more significant the restraining effect of the outer airbag 12 on the expansion of the inner airbag 13.

[0030] Specifically, the tensile strength of the outer airbag 12 is not less than 12 MPa, and the tensile modulus is greater than or equal to 0.24 GPa; the tensile strength of the inner airbag 13 is not less than 10 MPa, and the tensile modulus is less than or equal to 0.24 GPa, preferably less than or equal to 0.20 GPa. The tensile strength is high enough to ensure that neither the inner airbag 13 nor the outer airbag 12 will be damaged when the inner airbag 13 is inflated.

[0031] Specifically, the outer airbag 12 is made of either canvas (such as high-strength polyester industrial dipped coarse canvas) or rubber cloth (such as polyester-reinforced rubber cloth). The outer airbag 12 has excellent tensile strength and can withstand the tension of the inner airbag 13 after inflation. The size of the inflated outer airbag 12 is larger than the diameter of the pipe to be repaired to ensure that the flexible friction pad layer 11 remains in close contact with the inner wall of the pipe to be repaired during the pipe repair operation.

[0032] Specifically, the inner airbag 13 is made of either plastic or rubber. The plastic can be either PE or PVC, and the rubber can be any of natural rubber, styrene-butadiene rubber, butadiene rubber, neoprene rubber, nitrile rubber, hydrogenated nitrile rubber, or polyurethane rubber. The inner airbag 13 provides pressure support for the outer airbag 12. It has low tensile strength itself, but after inflation, it evenly transfers the expansion stress to the outer airbag 12. The inflated diameter of the inner airbag 13 is slightly larger than the internal space of the outer airbag 12 to ensure effective transfer of expansion stress. The volute-shaped inner airbag 13 is waterproof and leak-proof.

[0033] Specifically, the central flow pipe 2 has an air inlet / outlet port 14 that communicates with the inner airbag 13; the air inlet / outlet port 14 is connected to the air compressor through an air inlet / outlet pipe to control the expansion and deformation of the inner airbag 13. In the attached drawing, the double-headed arrows indicate the air inlet / outlet direction of the air inlet / outlet port 14.

[0034] Specifically, the flexible friction pad 11 is made of rubber, silicone, or latex tape. The flexible friction pad 11 is located on the outer surface of the outer airbag 12. When the outer airbag 12 is filled, it adheres tightly to the pipe to be repaired, which can increase the friction between the annular blocking airbag 1 and the pipe to be repaired. At the same time, due to the softness of the material, it can better adapt to the influence of the slight undulations, defects, sand particles, etc. on the inner wall of the pipe to be repaired, so that the annular blocking airbag 1 has a better pressing and water blocking effect.

[0035] Specifically, the inner membrane 123 is bonded to the outer wall of the central flow tube 2, and the flexible friction pad 11 is bonded to the outer membrane 121; the inner membrane 123, the outer membrane 121, and the two side membranes 122 are integrated or bonded together.

[0036] The annular blocking airbag 1 has a double-layer structure, with an inner airbag 13 and an outer airbag 12. When the tensile modulus of the inner airbag 13 is less than that of the outer airbag 12, the expansion deformation of the inner airbag 13 after inflation is greater than that of the outer airbag 12. Therefore, the outer airbag 12 will constrain the expansion deformation of the inner airbag 13, thereby constraining the lateral expansion deformation of the annular blocking airbag 1 along the axis of the central flow pipe 2. The outer airbag 12 adopts a size that matches the pipe to be repaired. Matching does not mean equal, but means that it can fit tightly against the inner wall of the pipe to be repaired after expansion, so that the annular blocking airbag 1 can generate sufficient expansion pressure on the pipe to be repaired, thereby generating sufficient friction between the flexible friction pad layer 11 and the pipe to be repaired to resist the internal water pressure of the pipe to be repaired.

[0037] It should be noted that the central flow pipe 2 adopts a prefabricated pipe section. The central flow pipe 2 is obtained by assembling adjacent pipe sections through flange 21. In actual engineering, an annular blocking airbag 1 can be installed on a pipe section. After the pipe section carrying the annular blocking airbag 1 is hoisted into the inspection well, the flanges 21 of the adjacent pipe sections can be connected.

[0038] Example 2

[0039] Please see Figures 1-2 and Figures 4-9This embodiment provides an annular blocking airbag for trenchless repair or detection of pipeline defects without interruption. The difference from Embodiment 1 is that: a tensile membrane 124 is further installed inside the outer airbag 12. The tensile membrane 124 is spirally arranged around the inner membrane 123, with its inner side fixedly connected to the inner membrane 123 and its outer side fixedly connected to the outer membrane 121. Its axial ends are respectively fixedly connected to two side membranes 122. The tensile membrane 124 further divides the annular cavity inside the outer airbag 12 into a volute-shaped cavity. A volute-shaped inner airbag 13 is installed inside the volute-shaped cavity. The tensile membrane 124 provides tension to the two side membranes 122 on the left and right sides of the outer airbag 12, further constraining the axial deformation of the volute-shaped inner airbag 13.

[0040] Specifically, the tensile modulus of the tensile membrane 124 is greater than or equal to the tensile modulus of the outer airbag 12. That is, the tensile membrane 124 can be made of the same material as the outer airbag 12, or it can be made of a material with better tensile properties that is compatible with and can be bonded to the outer airbag 12.

[0041] It should be noted that for pipes with smaller diameters or even smaller diameters to be repaired (e.g., below 1000mm), the radial expansion distance of the annular blocking airbag 1 is approximately 350mm or even smaller. In this case, a regular airbag or a regular double-layer airbag can be used. For pipes with diameters of around 1000mm and slightly larger, the method of outer airbag 12 (without tensile membrane 124) + inner airbag 13 in Example 1 can be used. For pipes with larger diameters to be repaired, the method of outer airbag 12 (with tensile membrane 124) + volute-shaped inner airbag 13 in Example 2 can be used. The number and spacing of the spiral layers of the tensile membrane 124 are adjusted according to the radial expansion distance of the annular blocking airbag 1.

[0042] It should be noted that the annular blocking airbag 1 in this application can be used in a pipeline defect water-filled non-destructive repair device and related products disclosed in Chinese invention patent CN118391536B, as well as in a pipeline defect water-filled CCTV detection device and related products disclosed in CN122281163B, and can also be used in products with similar requirements.

[0043] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A ring-shaped blocking airbag for trenchless repair or inspection of pipeline defects without interruption, characterized in that: It includes an annular external airbag (12) fixedly installed around the outer wall of the central flow tube (2), an inner airbag (13) installed inside the annular cavity of the external airbag (12), and a flexible friction pad layer (11) fixedly installed around the outer surface of the external airbag (12). The outer airbag (12) is also equipped with a tensile membrane (124), which further divides the annular cavity into a volute-shaped cavity; a volute-shaped inner airbag (13) is installed inside the volute-shaped cavity. When the inner airbag (13) is not inflated, the outer airbag (12) is attached to the outer wall of the central flow tube (2). After the inner airbag (13) is inflated, the outer airbag (12) is filled, so that the flexible friction pad (11) is tightly pressed against the inner wall of the pipe to be repaired. The tensile modulus of the inner airbag (13) is smaller than that of the outer airbag (12).

2. The annular blocking airbag for non-cut-off, trenchless repair or detection of pipeline defects according to claim 1, characterized in that: The external airbag (12) includes an inner membrane (123) that is fixedly installed around the outer wall of the central flow tube (2), two side membranes (122) that are fixedly installed at both ends of the inner membrane (123), and an outer membrane (121) that is fixedly connected to the two side membranes (122). The inner membrane (123), the outer membrane (121), and the two side membranes (122) form an annular cavity that accommodates the internal airbag (13).

3. The annular blocking airbag for non-cut-off, trenchless repair or detection of pipeline defects according to claim 2, characterized in that: The tensile modulus of the external airbag (12) is at least 1.2 times that of the internal airbag (13).

4. The annular blocking airbag for non-cut-off, trenchless repair or detection of pipeline defects according to claim 3, characterized in that: The tensile strength of the external airbag (12) is not less than 12 MPa and the tensile modulus is greater than or equal to 0.24 GPa; the tensile strength of the internal airbag (13) is not less than 10 MPa and the tensile modulus is less than or equal to 0.24 GPa.

5. The annular blocking airbag for non-interceptive trenchless repair or detection of pipeline defects according to claim 4, characterized in that: The external airbag (12) is made of either canvas or rubber sheet.

6. The annular blocking airbag for non-interceptive trenchless repair or detection of pipeline defects according to claim 4, characterized in that: The internal airbag (13) is made of either plastic or rubber. The plastic is made of either polyethylene or polyvinyl chloride, and the rubber is made of either natural rubber, styrene-butadiene rubber, butadiene rubber, chloroprene rubber, nitrile rubber, hydrogenated nitrile rubber, or polyurethane rubber.

7. The annular blocking airbag for trenchless repair or detection of pipeline defects without interruption, as described in claim 4, is characterized in that: The flexible friction pad (11) is made of rubber tape, silicone tape or latex tape.

8. The annular blocking airbag for non-cut-off, trenchless repair or detection of pipeline defects according to claim 2, characterized in that: The inner membrane (123) is bonded to the outer wall of the central flow tube (2), and the flexible friction pad (11) is bonded to the outer membrane (121); the inner membrane (123), the outer membrane (121), and the two side membranes (122) are integrated or bonded together.

9. The annular blocking airbag for non-interceptive trenchless repair or inspection of pipeline defects according to any one of claims 2-8, characterized in that: The tensile membrane (124) is spirally arranged around the inner membrane (123), with the inner side fixedly connected to the inner membrane (123) and the outer side fixedly connected to the outer membrane (121). The two ends of the axial direction are respectively fixedly connected to the two side membranes (122).

10. The annular blocking airbag for trenchless repair or detection of pipeline defects without interruption, as described in claim 9, is characterized in that: The tensile modulus of the tensile membrane (124) is greater than or equal to the tensile modulus of the external airbag (12).

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