Natural gas pipeline protection device

Abstract

The invention discloses a natural gas pipeline protection device which comprises a first reinforcing cylinder connected with a first pipeline in a sleeving mode and a second reinforcing cylinder connected with a second pipeline in a sleeving mode, and the first reinforcing cylinder and the second reinforcing cylinder are installed through a connecting flange. The top plate I and the top plate II are positioned in the middles of the reinforcing cylinder I and the reinforcing cylinder II; the first pressurizing sleeve plate is arranged on the outer side of the first top plate, the second pressurizing sleeve plate is arranged on the outer side of the second top plate, a first pull rod connected with the second reinforcing cylinder in an inserted mode is fixed to the first pressurizing sleeve plate, and a second pull rod connected with the first reinforcing cylinder in an inserted mode is fixed to the second pressurizing sleeve plate; the air inlet valve is installed on the first reinforcing cylinder or the second reinforcing cylinder. The strength of the connecting position of the first pipeline and the second pipeline can be improved, so that a gap is not prone to occurring between the first pipeline and the second pipeline, the connecting position of the first pipeline and the second pipeline is further reinforced through the pressure difference, and the situation that when the natural gas pipeline is located on the water surface, leakage occurs at the connecting position due to lack of support is reduced.

Description

Technical Field

[0001] This invention relates to the field of natural gas pipeline protection technology, and in particular to a natural gas pipeline protection device. Background Technology

[0002] Natural gas pipelines are pipelines that transport natural gas from extraction sites or processing plants to urban gas distribution centers or industrial users. Also known as gas transmission pipelines, they are the only way to transport large quantities of natural gas over land. Natural gas pipelines account for about half of the world's total pipeline length. As the mileage of natural gas pipelines increases annually, they inevitably cross rivers and other bodies of water. Because the entire pipeline requires supporting structures for fixation, sections of the pipeline may be suspended in mid-air. Figure 1 As shown, the traditional pipe connection method connects pipe 1 and pipe 2 through connecting flange 3 to achieve gas pipeline connection. When connecting flange 3 is in a suspended state, the uneven stress at the upper and lower parts of the joint of connecting flange 3 during long-term use can cause the connection to loosen and other reasons, resulting in pipeline leakage. Summary of the Invention

[0003] Based on this, it is necessary to provide a natural gas pipeline protection device to address the aforementioned technical problems. This device can strengthen the connection between pipeline one and pipeline two, making it less likely for gaps to occur between them. It also uses an inert gas inlet valve to pressurize the inner cavities of reinforcing cylinder one and reinforcing cylinder two, further reducing natural gas leakage at the connecting flange. The pressure difference causes pressurizing sleeve one and pressurizing sleeve two to push pipeline one and pipeline two towards the connecting flange simultaneously, further reinforcing the connection between pipeline one and pipeline two. This reduces the possibility of leakage at the connection due to lack of support when the natural gas pipeline is located on the water surface.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A natural gas pipeline protection device, comprising: A first reinforcing cylinder that is sleeved with pipe one, and a second reinforcing cylinder that is sleeved with pipe two, wherein the first reinforcing cylinder and the second reinforcing cylinder are installed together by connecting flanges; Top plate 1 and top plate 2 are located in the middle of reinforced cylinder 1 and reinforced cylinder 2, and top plate 1 is fixed to the outer ring of pipe 1, and top plate 2 is fixed to the outer ring of pipe 2; A pressure sleeve 1 is provided on the outer side of the top plate 1 and a pressure sleeve 2 is provided on the outer side of the top plate 2. The pressure sleeve 1 is fitted onto the pipe 1 and a tie rod 1 that is inserted into the reinforcing cylinder 2 is fixed on the pressure sleeve 1. The pressure sleeve 2 is fitted onto the pipe 2 and a tie rod 2 that is inserted into the reinforcing cylinder 1 is fixed on the pressure sleeve 2. An intake valve is installed on either reinforced cylinder one or reinforced cylinder two.

[0005] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, both the first and second reinforcing cylinders are fixed with annular side baffles. The first pressure sleeve is installed between the first top plate and the side baffle of the first reinforcing cylinder, and the second pressure sleeve is installed between the second top plate and the side baffle of the second reinforcing cylinder. The first pressure sleeve seals the gap between the first top plate and the side baffle of the first reinforcing cylinder, and the second pressure sleeve seals the gap between the second top plate and the side baffle of the second reinforcing cylinder, so that the first and second reinforcing cylinders and the outer ring of the connecting flange form a sealed space, which facilitates the filling of the inner cavity of the first and second reinforcing cylinders with inert gas or air, increasing their internal pressure and reducing gas leakage.

[0006] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, at least two tie rods are provided, and a negative pressure bushing two corresponding to the tie rods is installed on the reinforcing cylinder two. The tie rods are inserted into the inner cavity of the negative pressure bushing two, and the tie rods are inserted into the negative pressure bushing two on the reinforcing cylinder two. When the inner cavities of the reinforcing cylinder one and the reinforcing cylinder two are pressurized, due to the pressure difference between the inside and outside, the tie rods move outward along the negative pressure bushing two, and drive the pressurizing sleeve one to push the top plate one and the pipeline one toward the pipeline two, so that the connection between the pipeline one and the pipeline two is more secure.

[0007] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, at least two tie rods are provided. A negative pressure bushing corresponding to the tie rod is installed on the reinforcing cylinder. The tie rod is inserted into the inner cavity of the negative pressure bushing and the negative pressure bushing on the reinforcing cylinder. When the inner cavities of the reinforcing cylinder and the reinforcing cylinder are pressurized, due to the pressure difference between the inside and outside, the tie rod moves outward along the negative pressure bushing and drives the pressurizing sleeve plate to push the top plate and the pipeline towards a certain point of the pipeline, so that the connection between the pipeline and the pipeline is more secure.

[0008] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, the ends of the first and second pull rods are both fitted with sealing rings, and the outer ring of the sealing ring is in contact with the inner wall of the corresponding negative pressure bushing one or negative pressure bushing two, which can improve the sealing performance between the first pull rod and the second negative pressure bushing, and improve the sealing performance of the inner cavities of the first and second reinforcing cylinders.

[0009] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, both the first pressure sleeve and the second pressure sleeve are provided with limiting slots. The first pull rod passes through the limiting slot on the second pressure sleeve, and the second pull rod passes through the limiting slot on the first pressure sleeve. The positions of the first pressure sleeve and the second pressure sleeve are fixed by the second pull rod and the first pull rod, respectively, which facilitates the installation and limiting of the first and second pressure sleeves and facilitates the insertion and installation with the first and second negative pressure bushings.

[0010] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, the inner diameter of the side baffle of the reinforcing cylinder is larger than the outer diameter of the top plate, the outer diameter of the pressure sleeve is larger than the inner diameter of the side baffle of the reinforcing cylinder, and the inner diameter of the pressure sleeve is smaller than the outer diameter of the top plate. This allows the reinforcing cylinder to be directly fitted onto the pipeline without being affected by the top plate. Furthermore, the pressure sleeve seals the gap between the top plate and the side baffle of the reinforcing cylinder, thus sealing the inner cavity of the reinforcing cylinder.

[0011] In a preferred embodiment of the natural gas pipeline protection device provided by the present invention, the inner diameter of the second side baffle of the reinforcing cylinder is larger than the outer diameter of the second top plate, the outer diameter of the second pressure sleeve is larger than the inner diameter of the second side baffle of the reinforcing cylinder, and the inner diameter of the second pressure sleeve is smaller than the outer diameter of the second top plate. This allows the second reinforcing cylinder to be directly fitted onto the second pipeline without being affected by the second top plate. Furthermore, the second pressure sleeve seals the gap between the second top plate and the second side baffle of the tie rod, thus sealing the inner cavity of the second reinforcing cylinder.

[0012] As a preferred embodiment of the natural gas pipeline protection device provided by the present invention, both the first pressure sleeve and the second pressure sleeve are two-section structures, which are connected by bolts for easy installation and assembly of the device.

[0013] As a preferred embodiment of the natural gas pipeline protection device provided by the present invention, it further includes a gas pressure detection component and a gas detection component. The gas pressure detection component and the gas detection component are installed on the first or second reinforced cylinder. Using the installed gas pressure detection component, the pressure inside the first and second reinforced cylinders can be seen directly, which is convenient for maintenance personnel to understand the situation. The gas detection component can be a gas sensor, which can detect the content of natural gas inside the first and second reinforced cylinders and detect whether there is a leak at the connection point, thereby reducing safety hazards.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides a natural gas pipeline protection device in which a first reinforcing cylinder, a second reinforcing cylinder, and the outer ring of a connecting flange form a sealed space, which can strengthen the connection between the first and second pipelines, making it less likely for gaps to occur between them. The device uses an air inlet valve to fill the inner cavity of the first and second reinforcing cylinders with inert gas to pressurize them, further reducing natural gas leakage at the connecting flange. The pressure difference causes the first and second pressurizing sleeves to push the first and second pipelines towards the connecting flange simultaneously, further reinforcing the connection between the first and second pipelines and reducing the possibility of leakage at the connection due to lack of support when the natural gas pipeline is located on the water surface.

[0015] 2. The present invention provides a natural gas pipeline protection device, which involves sleeved and fixed reinforcing cylinders one and two onto pipeline one and pipeline two, respectively. At this time, pressure sleeve one seals the gap between top plate one and one side baffle of the reinforcing cylinder, and pressure sleeve two seals the gap between top plate two and the side baffle of the reinforcing cylinder two. This creates a sealed space between the reinforcing cylinders one and two and the outer ring of the connecting flange, thereby strengthening the connection between pipeline one and pipeline two and preventing gaps between them. Furthermore, an air inlet valve fills the inner cavity of the reinforcing cylinders one and two. Inert gas is introduced for pressurization to further prevent natural gas leakage at the connection flange. Since the pressure inside the first and second reinforcing cylinders is greater than the pressure on the outside, the pressure difference causes the end of the first tie rod to move towards the outer end of the second negative pressure sleeve. The end of the second tie rod moves along the outer end of the first negative pressure sleeve, and the first and second pressurizing sleeves push the first and second pipes towards the connection flange simultaneously, further reinforcing the connection between the first and second pipes. This reduces the possibility of leakage at the connection due to lack of support when the natural gas pipeline is located on the water surface. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the prior art structure provided in this application; Figure 2 A schematic diagram of the structure of the first and second reinforcing cylinders provided in this application after installation; Figure 3 The sectional view provided for this application; Figure 4 This application provides exploded view and structural schematic diagram of part of the structure; Figure 5This is a schematic diagram of the tie rod and sealing ring structure provided in this application.

[0018] The markings in the diagram are explained as follows: 1. Pipeline 1; 2. Pipeline 2; 3. Connecting flange; 4. Reinforcing sleeve 1; 5. Reinforcing sleeve 2; 6. Gas pressure detection assembly; 7. Inlet valve; 8. Gas detection assembly; 9. Negative pressure bushing 2; 10. Negative pressure bushing 1; 11. Pressurizing sleeve 1; 12. Top plate 1; 13. Pressurizing sleeve 2; 14. Top plate 2; 15. Tie rod 2; 16. Tie rod 1; 17. Limiting groove; 18. Sealing ring; 19. Side stop. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0020] As described in the background art, when the connecting flange 3 is in a suspended state, due to the effect of gravity, gaps will gradually appear at the joint of the connecting flange 3, leading to pipeline leakage and causing safety hazards.

[0021] This invention provides a natural gas pipeline protection device. By fitting reinforcing cylinder 4 and reinforcing cylinder 5 onto pipeline 1 and pipeline 2 respectively, and fixing them in place, pressure sleeve 11 seals the gap between top plate 12 and the side wall of reinforcing cylinder 4, and pressure sleeve 13 seals the gap between top plate 14 and the side wall of reinforcing cylinder 5. This creates a sealed space between reinforcing cylinder 4, reinforcing cylinder 5, and the outer ring of connecting flange 3, strengthening the connection between pipeline 1 and pipeline 2, preventing gaps between them, and using inlet valve 7 to control the internal pressure of reinforcing cylinder 4 and reinforcing cylinder 5. The cavity is filled with inert gas for pressurization to further prevent natural gas leakage at the connecting flange 3. Since the pressure inside the reinforcing cylinder 1 4 and reinforcing cylinder 2 5 is greater than the pressure outside, the pressure difference causes the end of the tie rod 1 16 to move towards the outer end of the negative pressure sleeve 2 9, and the end of the tie rod 2 15 to move along the outer end of the negative pressure sleeve 10. The pressurizing sleeve 1 11 and pressurizing sleeve 2 13 push the pipe 1 1 and pipe 2 2 towards the connecting flange 3 simultaneously, further reinforcing the connection between pipe 1 1 and pipe 2 2, reducing the possibility of leakage at the connection due to lack of support when the natural gas pipeline is located at the water surface.

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0023] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Example

[0025] Please refer to Figures 2 to 3 A natural gas pipeline protection device includes a reinforcing cylinder 4 sleeved with a pipeline 1 and a reinforcing cylinder 5 sleeved with a pipeline 2. The reinforcing cylinder 4 and the reinforcing cylinder 5 are installed together by connecting flanges. A top plate 12 and a top plate 14 are located in the middle of the reinforcing cylinder 4 and the reinforcing cylinder 2, respectively. The top plate 12 is fixed to the outer ring of the pipeline 1 and the top plate 14 is fixed to the outer ring of the pipeline 2. Pushing the top plate 12 can move the pipeline 1 and pushing the top plate 14 can move the pipeline 2.

[0026] It is worth mentioning that, such as Figures 2 to 3 As shown, a pressure sleeve 11 is provided on the outside of the top plate 12, and the pressure sleeve 11 is fitted onto the pipe 1. A tie rod 16, which is inserted into the reinforcing cylinder 5, is fixed on the pressure sleeve 11. A pressure sleeve 23 is provided on the outside of the top plate 14, and a tie rod 25, which is inserted into the reinforcing cylinder 4, is fixed on the pressure sleeve 23. A side baffle 19 with an annular structure is fixed on the outside of both the reinforcing cylinder 4 and the reinforcing cylinder 25. The pressure sleeve 11 is installed on the side baffles of the top plate 12 and the reinforcing cylinder 4. Between 19, pressure sleeve 2 13 is installed between top plate 2 14 and side baffle 19 of reinforcing cylinder 2 5. Pressure sleeve 1 11 seals the gap between top plate 1 12 and side baffle 19 of reinforcing cylinder 1 4, and pressure sleeve 2 13 seals the gap between top plate 2 14 and side baffle 19 of reinforcing cylinder 2 5, so that reinforcing cylinder 1 4, reinforcing cylinder 2 5 and the outer ring of connecting flange 3 form a sealed space, which facilitates the filling of inert gas or air into the inner cavity of reinforcing cylinder 1 4 and reinforcing cylinder 2 5, increases its internal pressure and reduces gas leakage.

[0027] In addition, such as Figure 3As shown, at least two tie rods 16 are provided. A negative pressure bushing 9 corresponding to tie rod 16 is installed on the reinforcing cylinder 25. Tie rod 16 is inserted into the inner cavity of negative pressure bushing 9. When the inner cavities of reinforcing cylinder 4 and reinforcing cylinder 25 are pressurized, due to the pressure difference between the inside and outside, tie rod 16 moves outward along negative pressure bushing 9, and drives pressurizing sleeve plate 11 to push top plate 12 and pipe 1 towards pipe 22, making the connection between pipe 11 and pipe 22 more secure.

[0028] Furthermore, at least two tie rods 15 are provided. A negative pressure bushing 10 corresponding to tie rod 15 is installed on the reinforcing cylinder 4. Tie rod 15 is inserted into the inner cavity of negative pressure bushing 10. Tie rod 15 is inserted into the negative pressure bushing 10 on the reinforcing cylinder 4. When the inner cavities of the reinforcing cylinder 4 and the reinforcing cylinder 2 are pressurized, due to the pressure difference between the inside and outside, tie rod 15 moves outward along negative pressure bushing 10, and drives the pressurizing sleeve plate 2 13 to push the top plate 2 14 and the pipe 2 2 towards the pipe 1, making the connection between pipe 1 and pipe 2 2 more secure.

[0029] It is worth mentioning that, such as Figure 2 As shown, the intake valve 7 is installed on either the first reinforcing cylinder 4 or the second reinforcing cylinder 5. The intake valve 7 can be used to fill the inner cavity of the first reinforcing cylinder 4 and the second reinforcing cylinder 5 with inert gas to pressurize them, further preventing natural gas leakage at the connecting flange 3. In addition, a one-way valve is installed on the intake valve 7 to prevent other leaks.

[0030] In addition, both pressure sleeve 11 and pressure sleeve 2 13 have limiting slots 17. Pull rod 1 16 passes through the limiting slot 17 on pressure sleeve 2 13, and pull rod 2 15 passes through the limiting slot 17 on pressure sleeve 11. The positions of pressure sleeve 11 and pressure sleeve 2 13 are fixed by pull rod 2 15 and pull rod 1 16 respectively, which facilitates the installation and limiting of pressure sleeve 2 13 and pressure sleeve 11, and facilitates the insertion and installation with negative pressure bushing 10 and negative pressure bushing 2 9.

[0031] In this embodiment, as Figure 2 As shown, it also includes a gas pressure detection component 6 and a gas detection component 8. The gas pressure detection component 6 and the gas detection component 8 are installed on the first reinforced cylinder 4 or the second reinforced cylinder 5. Using the installed gas pressure detection component 6, the pressure inside the cavity of the first reinforced cylinder 4 and the second reinforced cylinder 5 can be seen directly, which is convenient for maintenance personnel to understand the situation. The gas detection component 8 can be a gas sensor, which can detect the content of natural gas inside the cavity of the first reinforced cylinder 4 and the second reinforced cylinder 5, and detect whether there is a leak at the connection point, reducing safety hazards. Example

[0032] The natural gas pipeline protection device provided in Example 1 is further optimized, specifically, as follows: Figure 4 As shown, the inner diameter of the side baffle of the reinforcing cylinder-4 is larger than the outer diameter of the top plate-12, and the outer diameter of the pressure sleeve-11 is larger than the inner diameter of the side baffle of the reinforcing cylinder-4. The inner diameter of the pressure sleeve-11 is smaller than the outer diameter of the top plate-12, which makes it convenient to directly sleeve the reinforcing cylinder-4 on the pipe-1 without being affected by the top plate-12. Furthermore, the pressure sleeve-11 is used to seal the gap between the top plate-12 and the side baffle of the reinforcing cylinder-4, thus sealing the inner cavity of the reinforcing cylinder-4.

[0033] Furthermore, the inner diameter of the side baffle of the second reinforcing cylinder 2 5 is larger than the outer diameter of the second top plate 2 14, the outer diameter of the second pressure sleeve 2 13 is larger than the inner diameter of the side baffle of the second reinforcing cylinder 2 5, and the inner diameter of the second pressure sleeve 2 13 is smaller than the outer diameter of the second top plate 2 14. This makes it convenient to directly sleeve the second reinforcing cylinder 2 5 onto the second pipe 2 2 without being affected by the second top plate 2 14. In addition, the second pressure sleeve 2 13 is used to seal the gap between the second top plate 2 14 and the side baffle of the second tie rod 2 15, thus sealing the inner cavity of the second reinforcing cylinder 2 5.

[0034] It is worth mentioning that, such as Figure 5 As shown, both the first pressure plate 11 and the second pressure plate 13 are two-section structures, which are connected by bolts for easy installation and assembly of the device.

[0035] In addition, such as Figure 5 As shown, both the ends of pull rod 16 and pull rod 2 are fitted with sealing rings 18, and the outer ring of the sealing ring 18 is in contact with the inner wall of the corresponding negative pressure bushing 10 or negative pressure bushing 2 9, which can improve the sealing between pull rod 16 and negative pressure bushing 2 9, and improve the sealing of the inner cavity of reinforcing cylinder 1 4 and reinforcing cylinder 2 5.

[0036] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] Obviously, the embodiments described above are merely some embodiments of the present invention, not all embodiments. The accompanying drawings show preferred embodiments of the present invention, but do not limit the patent scope of the present invention. The present invention can be implemented in many different forms; rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the patent protection scope of this invention.

Claims

1. A natural gas pipeline protection device, characterized in that, It includes: The first (4) of the reinforcing cylinder is sleeved with the first (1) pipe and the second (5) of the reinforcing cylinder is sleeved with the second (2) pipe, and the first (4) and the second (5) are installed by connecting flanges; Top plate 1 (12) and top plate 2 (14) are located in the middle of reinforcing cylinder 1 (4) and reinforcing cylinder 2 (5), and top plate 1 (12) is fixed to the outer ring of pipe 1 (1), and top plate 2 (14) is fixed to the outer ring of pipe 2 (2); A pressure sleeve plate 1 (11) is set on the outside of the top plate 1 (12) and a pressure sleeve plate 2 (13) is set on the outside of the top plate 2 (14). The pressure sleeve plate 1 (11) is sleeved on the pipe 1 (1) and a tie rod 1 (16) that is inserted into the reinforcing cylinder 2 (5) is fixed on the pressure sleeve plate 1 (11). The pressure sleeve plate 2 (13) is sleeved on the pipe 2 (2) and a tie rod 2 (15) that is inserted into the reinforcing cylinder 1 (4) is fixed on the pressure sleeve plate 2 (13). An intake valve (7) is installed on either the first reinforcing cylinder (4) or the second reinforcing cylinder (5).

2. A natural gas pipeline protection device according to claim 1, characterized in that, Both the first reinforcing cylinder (4) and the second reinforcing cylinder (5) are fixed with side guards (19) of annular structure. The first pressure sleeve (11) is installed between the first top plate (12) and the side guard (19) of the first reinforcing cylinder (4). The second pressure sleeve (13) is installed between the second top plate (14) and the side guard (19) of the second reinforcing cylinder (5).

3. A natural gas pipeline protection device according to claim 2, characterized in that, At least two pull rods are provided. A negative pressure bushing two (9) corresponding to the pull rods is installed on the reinforcing cylinder two (5). The pull rods are inserted into the inner cavity of the negative pressure bushing two (9).

4. A natural gas pipeline protection device according to claim 3, characterized in that, At least two tie rods (15) are provided. A negative pressure bushing (10) corresponding to tie rod (15) is installed on the reinforcing cylinder (4). Tie rod (15) is inserted into the inner cavity of negative pressure bushing (10).

5. A natural gas pipeline protection device according to claim 4, characterized in that, Both the ends of the first pull rod (16) and the second pull rod (15) are fitted with sealing rings (18), and the outer ring of the sealing ring (18) is in contact with the inner wall of the corresponding negative pressure bushing (10) or negative pressure bushing (9).

6. A natural gas pipeline protection device according to claim 5, characterized in that, Both the first pressure plate (11) and the second pressure plate (13) have a limiting groove (17). The first pull rod (16) passes through the limiting groove (17) on the second pressure plate (13), and the second pull rod (15) passes through the limiting groove (17) on the first pressure plate (11).

7. A natural gas pipeline protection device according to claim 2, characterized in that, The inner diameter of the side baffle of the reinforcing cylinder (4) is greater than the outer diameter of the top plate (12), the outer diameter of the pressure sleeve (11) is greater than the inner diameter of the side baffle of the reinforcing cylinder (4), and the inner diameter of the pressure sleeve (11) is less than the outer diameter of the top plate (12).

8. A natural gas pipeline protection device according to claim 7, characterized in that, The inner diameter of the side baffle of the second reinforcing cylinder (5) is greater than the outer diameter of the second top plate (14), the outer diameter of the second pressure sleeve (13) is greater than the inner diameter of the side baffle of the second reinforcing cylinder (5), and the inner diameter of the second pressure sleeve (13) is less than the outer diameter of the second top plate (14).

9. A natural gas pipeline protection device according to claim 8, characterized in that, Both the first pressure plate (11) and the second pressure plate (13) are two-section structures and are connected by bolts.

10. A natural gas pipeline protection device according to claim 9, characterized in that, It also includes a pressure detection component (6) and a gas detection component (8), which are installed on the first reinforcing cylinder (4) or the second reinforcing cylinder (5).

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