A delivery pipe for a gas-liquid mixed transmission and pressurization system

Abstract

The present invention discloses a delivery pipe for a gas-liquid mixed transmission boosting system, including a delivery pipe connected to the output end of a booster, the delivery pipe is laid on a seabed sand bed, a protective shell is provided on the outer wall of the delivery pipe along its length direction, a sealed cavity is provided inside the protective shell, the cavity is filled with gas, an air port is provided at the bottom of the protective shell, a sealing plate integrally formed with the protective shell is provided inside the air port, the sealing plate seals the air port, the thickness of the sealing plate is less than the thickness of the bottom wall of the protective shell, when the delivery pipe is close to the sand bed, the pressure difference between the water pressure outside the protective shell and the air pressure inside is greater than the threshold of the pressure required for the sealing plate to break, when the sealing plate is broken, the gas in the cavity is instantly ejected downward along the air port and disturbs the sand below, the threshold is greater than the air pressure in the cavity and less than the water pressure when close to the sand bed. The delivery pipe in the present invention can be self-buried during laying, the delivery pipe is less disturbed by ocean currents in the later stage, the delivery pipe is not easy to move laterally, and the connection of the delivery pipe is not easy to be damaged and leaked.

Description

Technical Field

[0001] The invention relates to the technical field of delivery pipes, and in particular to a delivery pipe used in a gas-liquid mixed delivery and pressurization system. Background Art

[0002] At present, the mixed gas and liquid transportation on the seabed is realized by the combination of a booster and a transmission pipe, and is transported to the sea surface oil storage platform or offshore processing facilities through the seabed transmission pipeline. The length of the seabed transmission pipeline is determined by the distance from the wellhead to the sea surface platform or offshore processing facility. The transmission pipeline is generally laid on the sand bed on the seabed, which has a large amount of sea sand. The transmission pipe on the sand bed is often disturbed by the ocean current, which makes it easy for the transmission pipe to move horizontally on the sand bed, which makes it easy for the connection of the transmission pipe to be damaged and leaked. Summary of the invention

[0003] The purpose of the present invention is to provide a delivery pipe for a gas-liquid mixed transmission and boosting system, which can be buried in the sea sand during laying, so that the delivery pipe is less disturbed by ocean currents in the later stage, the delivery pipe is not easy to move laterally, and the connection of the delivery pipe is not easy to be damaged and leaked.

[0004] In order to solve the above technical problems, the present invention adopts the following solutions: A delivery pipe for a gas-liquid mixed transmission and pressurization system comprises a delivery pipe connected to an output end of a supercharger, wherein the delivery pipe is laid on a sand bed on the seabed, a flexible protective shell is provided on an outer wall of the delivery pipe along its length direction, a sealed cavity is provided inside the protective shell, the cavity is filled with gas, an air port is provided at the bottom of the protective shell, a sealing plate integrally formed with the protective shell is provided in the air port, the sealing plate seals the air port, the thickness of the sealing plate is less than the thickness of the bottom wall of the protective shell, when the delivery pipe is close to the sand bed, the pressure difference between the water pressure outside the protective shell and the air pressure inside the protective shell is greater than the threshold value of the pressure required for the sealing plate to break, when the sealing plate is broken, the gas in the cavity is instantly ejected downward along the air port and disturbs the sand below, and the threshold value is greater than the air pressure in the cavity and less than the water pressure when close to the sand bed.

[0005] In this solution, the booster provides power for gas-liquid mixed transportation. The delivery pipe is laid on the sand bed on the seabed and is used to transmit the gas-liquid mixture. The protective shell is arranged along the length of the delivery pipe and has a sealed cavity inside. The cavity is filled with gas, which may include nitrogen, air or other inert gases. The gas port is located at the bottom of the protective shell and is used to release the gas in the cavity under specific conditions. The sealing plate is integrally formed with the protective shell and is used to seal the gas port. The thickness of the sealing plate is less than the thickness of the bottom wall of the protective shell and is designed to break under a specific water pressure. Under normal water pressure, the protective shell and the cavity inside it remain intact, providing additional protection for the delivery pipe. The gas in the cavity maintains a certain pressure, but it is lower than the water pressure near the sand bed where the delivery pipe needs to be installed. When the delivery pipe is close to the sand bed in the installation area, the pressure difference between the water pressure outside the protective shell and the air pressure inside exceeds the pressure threshold required for the sealing plate to break, and the sealing plate breaks. After the sealing plate breaks, the gas in the cavity instantly sprays downward through the air port, disturbing the sand below. Under the action of the airflow, the sand on the sand bed is lifted up to form a groove on the sand bed. The delivery pipe and the protective shell fall into the groove, eliminating the step of artificially opening the groove. The lifted sand falls freely after a period of time and covers the protective shell, thus forming a self-burying effect. The protective shell is buried under the sand bed together with the delivery pipe, which reduces the disturbance of the ocean current to the delivery pipe, and the delivery pipe is not easy to move laterally, and the connection of the delivery pipe is not easy to be damaged and leaked. At the same time, the protective shell can also protect the delivery pipe from the impact and damage of large fish. The protective shell also increases the contact area between the delivery pipe and the sand bed, further ensuring the stability of the delivery pipe on the seabed.

[0006] Optionally, the protective shells are evenly spaced along the length of the conveying pipe or wrap the entire conveying pipe.

[0007] Optionally, the delivery pipe is located in the middle of the cavity, and a protective rubber sleeve is provided on the outside of the delivery pipe, and the protective rubber sleeve is fixedly connected to the inner wall of the protective shell.

[0008] Optionally, a connecting plate made of the same material as the protective shell is fixed on the outer wall of the protective rubber sleeve, and the connecting plate is fixedly connected to the inner wall of the protective shell.

[0009] Optionally, the protective shell is welded by a top plate, a bottom plate and a side plate, the top plate is an arc-shaped plate, the bottom plate is an arc-shaped plate or a straight plate, the air inlet is opened on the bottom plate and is located on both sides of the conveying pipe, the thickness of the sealing plate is smaller than the thickness of the bottom plate, the length direction of the protective shell is perpendicular to the length direction of the conveying pipe, the conveying pipe passes through the side plate, and the side plate is sealed and connected to the outer wall of the conveying pipe.

[0010] Optionally, a plurality of groups of support members for maintaining space in the cavity are provided in the cavity, one end of the support member is fixedly connected to the bottom surface of the top plate, and the other end is fixedly connected to the top surface of the bottom plate.

[0011] Optionally, the support member is composed of two flexible reinforcing rods, the two reinforcing rods cross each other, and two ends of the reinforcing rods are respectively connected to the bottom surface of the top plate and the top surface of the bottom plate.

[0012] Optionally, after the gas in the cavity is ejected, the protective shell and the delivery pipe fall onto the sand bed under the action of their own weight, and seawater enters the cavity through the gas port until the cavity is filled with seawater.

[0013] Optionally, a plurality of oblique teeth are provided on the bottom surface of the bottom plate, with the center point of the bottom plate as the dividing point, and the directions of the oblique teeth on both sides of the center point are opposite.

[0014] Optionally, the bevel teeth on the right side of the center point are inserted into the sand bed to the right, and the bevel teeth on the left side are inserted into the sand bed to the left.

[0015] The present invention has the beneficial effects: In the present invention, when the conveying pipe is close to the sand bed of the installation area, the seal plate breaks when the pressure difference between the water pressure outside the protective shell and the air pressure inside exceeds the pressure threshold required for the seal plate to break. After the seal plate breaks, the gas in the cavity instantly sprays downward through the air port, disturbing the sand below. Under the action of the airflow, the sand on the sand bed is lifted up to form a groove on the sand bed. The conveying pipe and the protective shell fall into the groove, eliminating the step of manually opening the groove. The lifted sand falls freely after a period of time and covers the protective shell, thus forming a self-burying effect. The protective shell is buried under the sand bed together with the conveying pipe, thus reducing the disturbance of the ocean current to the conveying pipe, and the conveying pipe is not easy to move laterally, and the connection of the conveying pipe is not easy to be damaged and leaked. At the same time, the protective shell can also protect the conveying pipe from the impact and damage of large fish. The protective shell also increases the contact area between the conveying pipe and the sand bed, further ensuring the stability of the conveying pipe on the seabed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 Schematic diagram of the structure in which the bottom plate is a flat plate; Figure 3 The schematic diagram of the structure is that the bottom plate is an arc-shaped plate; Figure 4 It is the connection structure diagram of the side plate, top plate and bottom plate; Figure 5 Schematic diagram of the structure for blowing sand near the sand bed in the conveying pipe.

[0017] Figure numerals: 1-conveying pipe, 2-protective shell, 201-top plate, 202-bottom plate, 203-side plate, 3-cavity, 4-air port, 5-sealing plate, 6-reinforcement rod, 7-sand bed, 8-oblique teeth, 9-protective rubber sleeve, 10-connecting plate, 11-groove. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0019] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inside", "outside", "front", "back", "top", "bottom" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0020] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed", "opened", "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] A delivery pipe for a gas-liquid mixed transmission and boosting system comprises a delivery pipe 1 connected to an output end of a booster, wherein the delivery pipe 1 is laid on a sand bed 7 on the seabed, a flexible protective shell 2 is provided on the outer wall of the delivery pipe 1 along its length direction, a sealed cavity 3 is provided inside the protective shell 2, the cavity 3 is filled with gas, an air port 4 is provided at the bottom of the protective shell 2, a sealing plate 5 integrally formed with the protective shell 2 is provided inside the air port 4, the sealing plate 5 seals the air port 4, and the thickness of the sealing plate 5 is less than the thickness of the bottom wall of the protective shell 2, when the delivery pipe 1 is close to the sand bed 7, the pressure difference between the water pressure outside the protective shell 2 and the air pressure inside is greater than the threshold value of the pressure required to break the sealing plate 5, when the sealing plate 5 is broken, the gas in the cavity 3 is instantly ejected downward along the air port 4 and disturbs the sand below, and the threshold value is greater than the air pressure in the cavity 3 and less than the water pressure when close to the sand bed 7.

[0022] In this embodiment, the booster (not shown in the figure) provides power for the mixed gas-liquid transportation, which belongs to the prior art. The output end of the booster is connected to the delivery pipe 1, which is laid on the sand bed 7 on the seabed and is used to transmit the gas-liquid mixture. The flexible protective shell 2 is arranged along the length direction of the delivery pipe 1, and has a sealed cavity 3 inside. The cavity 3 is filled with gas, which may include nitrogen, air or other inert gases. The gas port 4 is located at the bottom of the protective shell 2 and is used to release the gas in the cavity 3 under specific conditions. The sealing plate 5 is integrally formed with the protective shell 2 and is used to seal the gas port 4. The thickness of the sealing plate 5 is less than the thickness of the bottom wall of the protective shell 2, and is designed to break under a specific water pressure. Under normal water pressure, the protective shell 2 and the cavity 3 inside it remain intact, providing additional protection for the delivery pipe 1. The gas in the cavity 3 maintains a certain pressure, but it is lower than the water pressure near the sand bed 7 where the delivery pipe 1 needs to be installed. Figure 5 As shown, when the conveying pipe 1 is close to the sand bed 7 of the installation area, the pressure difference between the water pressure outside the protective shell 2 and the air pressure inside exceeds the pressure threshold required for the sealing plate 5 to break, and the sealing plate 5 breaks. After the sealing plate 5 breaks, the gas in the cavity 3 is instantly ejected downward through the air port 4, disturbing the sand below. Under the action of the airflow, the sand on the sand bed 7 is lifted up to form a groove 11 on the sand bed 7. The conveying pipe 1 and the protective shell 2 fall into the groove 11, eliminating the step of manually opening the groove 11. The lifted sand falls freely after a period of time and covers the protective shell 2, thus forming a self-burying effect. The protective shell 2 is buried under the sand bed 7 together with the conveying pipe 1, thus reducing the disturbance of the ocean current to the conveying pipe 1, and the conveying pipe 1 is not easy to move horizontally, and the connection of the conveying pipe 1 is not easy to be damaged and leaked. At the same time, the protective shell 2 can also protect the conveying pipe 1 from the impact damage of large fish, and the protective shell 2 also increases the contact area between the conveying pipe 1 and the sand bed 7, further ensuring the stability of the conveying pipe 1 on the seabed.

[0023] Furthermore, the protective shells 2 are evenly distributed along the length direction of the delivery pipe 1 or wrap the entire delivery pipe 1 .

[0024] Specifically, Figure 1 As shown, the interval installation means that the protective shell 2 does not continuously wrap the entire conveying pipe 1, but is installed at specific intervals along the length direction of the conveying pipe 1. The protective shell 2 with uniform intervals can reduce material costs while ensuring a certain protection effect. Wrapping the entire conveying pipe 1 specifically means that the protective shell 2 continuously and uninterruptedly wraps the entire conveying pipe 1. This design provides maximum protection. However, the protective shell 2 that wraps the entire conveying pipe 1 requires more materials and higher construction costs. The choice of design method depends on factors such as specific engineering requirements, the characteristics of the seabed environment, and economic costs. In actual applications, trade-offs and choices can be made based on actual conditions to ensure the safe operation of the conveying pipe 1 and maximize economic benefits.

[0025] Furthermore, the delivery pipe 1 is located in the middle of the cavity 3 , and a protective rubber sleeve 9 is provided on the outside of the delivery pipe 1 , and the protective rubber sleeve 9 is fixedly connected to the inner wall of the protective shell 2 .

[0026] Furthermore, a connecting plate 10 made of the same material as the protective shell 2 is fixed on the outer wall of the protective rubber sleeve 9 , and the connecting plate 10 is fixedly connected to the inner wall of the protective shell 2 .

[0027] Specifically, Figure 2 As shown, the conveying pipe 1 is located in the middle of the cavity 3. This design ensures that the conveying pipe 1 is evenly protected inside the cavity 3. Whether it is the water pressure from above or the potential threat from the sand bed 7 below, the cavity 3 can provide effective buffering. The protective rubber sleeve 9 sleeved on the outside of the conveying pipe 1 further enhances the protection ability of the conveying pipe 1. The protective rubber sleeve 9 is usually made of soft and durable materials, such as rubber or synthetic rubber. These materials can adapt well to the complexity of the seabed environment and changes in water pressure. The connecting plate 10 fixed on the outer wall of the protective rubber sleeve 9 is fixedly connected to the inner wall of the protective shell 2. This design ensures the stability and reliability between the protective rubber sleeve 9 and the protective shell 2. The connecting plate 10 is usually made of the same or similar material as the protective shell 2 to ensure its strength and corrosion resistance. Through the fixing effect of the connecting plate 10, the protective rubber sleeve 9 can fit tightly on the conveying pipe 1 and provide additional support and protection. Through the combined effects of the cavity 3, the protective rubber sleeve 9 and the connecting plate 10, the system provides multi-level protection for the delivery pipe 1. This design not only improves the water pressure resistance of the delivery pipe 1, but also enhances its ability to resist external threats (such as submarine landslides, rock impacts, etc.); the fixing effect of the connecting plate 10 forms a stable connection structure between the protective rubber sleeve 9 and the protective shell 2, which helps to reduce the shaking and displacement of the delivery pipe 1 in the submarine environment, thereby improving the stability of the entire system.

[0028] Furthermore, the protective shell 2 is formed by molten welding or integrally forming a top plate 201, a bottom plate 202 and a side plate 203. The top plate 201 is an arc-shaped plate, the bottom plate 202 is an arc-shaped plate or a straight plate, the air port 4 is opened on the bottom plate 202 and is located on both sides of the conveying pipe 1, the thickness of the sealing plate 5 is less than the thickness of the bottom plate 202, the length direction of the protective shell 2 is perpendicular to the length direction of the conveying pipe 1, the conveying pipe 1 passes through the side plate 203, and the side plate 203 is sealed and connected to the outer wall of the conveying pipe 1.

[0029] Specifically, Figure 4As shown, the protective shell 2 is welded by a top plate 201, a bottom plate 202 and a side plate 203 to form a closed structure. The top plate 201 is designed as an arc plate, which helps to disperse the water pressure from above and improve the stability of the structure. At the same time, when the ocean current contacts the protective shell 2, it has better permeability, and the impact on the protective shell 2 is small, and then the impact on the conveying pipe 1 is small, so that the conveying pipe 1 is not easy to move laterally under the action of the ocean current. Lateral movement refers to translation along the sand bed 7, such as Figure 2 and Figure 3 As shown, the bottom plate 202 can be a curved plate or a straight plate, depending on the seabed topography and engineering requirements. The curved bottom plate can better adapt to the uneven seabed surface, while the straight bottom plate is convenient for construction and installation. Whether it is a curved bottom plate or a straight bottom plate, it can increase the contact area with the sand bed 7, thereby improving the stability of the conveying pipe 1 under the action of ocean currents. An opening is provided on the side plate 203 to allow the conveying pipe 1 to pass through, and the side plate 203 is welded to the outer wall of the conveying pipe 1. The air port 4 is opened on the bottom plate 202 and is located on both sides of the conveying pipe 1. This design allows the gas in the cavity 3 to spray downward when the sealing plate 5 is broken, disturbing the sand below and lifting the sand to achieve the subsequent self-burying of the conveying pipe 1. The thickness of the sealing plate 5 is less than that of the bottom plate 202, which is to ensure that the sealing plate 5 can be broken when a certain water pressure difference is reached. The thickness design of the sealing plate 5 needs to be accurately calculated based on the air pressure in the inner cavity and the water pressure when close to the sand bed 7, so as to ensure that it remains intact under normal seabed water pressure, and can be quickly broken under high pressure at a predetermined position. In this embodiment, the sealing plate 5 is broken when it is about 0.5 meters close to the sand bed. For example: the pressure required for the sealing plate 5 to break is 100N, the air pressure in the inner cavity is 50N, and the water pressure is 150N when the pipeline is 0.5m above the sand bed 7. Then, when the conveying pipe 1 continues to fall, the water pressure is greater than 150N, and the pressure difference between the inside and outside of the protective shell 2 will be greater than 100N. At this time, the sealing plate 5 will be broken, and the gas in the cavity 3 will be squeezed out under the action of water pressure. The length direction of the protective shell 2 is perpendicular to the length direction of the conveying pipe 1. This design enables the protective shell 2 to more effectively disperse the water pressure from the direction of the ocean current.

[0030] Furthermore, a plurality of support members for maintaining space in the cavity 3 are provided in the cavity 3 , one end of the support member is fixedly connected to the bottom surface of the top plate 201 , and the other end is fixedly connected to the top surface of the bottom plate 202 .

[0031] Furthermore, the support member is composed of two reinforcing rods 6 , which cross each other, and two ends of the reinforcing rods 6 are respectively connected to the bottom surface of the top plate 201 and the top surface of the bottom plate 202 .

[0032] Specifically, Figure 2As shown, the main function of the support member is to maintain a certain spatial structure of the cavity 3 after the gas is squeezed out. The support member is composed of two flexible reinforcing rods 6, which cross each other in the cavity 3 to form a stable support structure. The two ends of the reinforcing rod 6 are respectively connected to the bottom surface of the top plate 201 and the top surface of the bottom plate 202, and the firmness of the connection is ensured by molten welding or other fixing methods. The layout of the two reinforcing rods 6 crossing each other enables the support member to form a stable triangular support structure in the cavity 3. This structure can effectively disperse and resist pressure from all directions, improve the overall strength of the protective shell 2, and ensure that a certain space can be maintained inside the cavity 3 after the protective shell 2 is squeezed. The spatial area at this time is smaller than the initial state. Since the cavity 3 can still maintain a certain space after being squeezed, seawater can enter from the air port 4 later. With the entry of seawater and the action of the support member, the cavity 3 gradually recovers.

[0033] Furthermore, after the gas in the cavity 3 is ejected, the protective shell 2 together with the delivery pipe 1 falls onto the sand bed 7 under the action of its own weight, and seawater enters the cavity 3 from the gas port 4 until the cavity 3 is filled with seawater.

[0034] Specifically, when the conveying pipe 1 is close to the sand bed 7, the sealing plate 5 will be broken, and the gas in the cavity 3 will be squeezed and ejected rapidly. As the gas is ejected, the pressure in the cavity 3 will drop rapidly, causing the pressure difference between the inside and outside of the protective shell 2 to increase. Under the action of its own weight, the protective shell 2 together with the conveying pipe 1 will begin to fall until it contacts the sand bed 7. Seawater will enter the cavity 3 through the air port 4. As time goes by, seawater will gradually fill the entire cavity 3. The seawater filling the cavity 3 increases the weight of the protective shell 2. Therefore, the overall weight of the protective shell 2 and the conveying pipe 1 increases. In this way, the conveying pipe 1 is less affected by the disturbance of the ocean current on the sand bed 7, the self-weight increases, and the stability of the conveying pipe 1 is further improved.

[0035] Furthermore, a plurality of oblique teeth 8 are provided on the bottom surface of the bottom plate 202, with the center point of the bottom plate 202 as a dividing point, and the oblique teeth 8 on both sides of the center point are in opposite directions.

[0036] Furthermore, the oblique teeth 8 on the right side of the center point are inserted into the sand bed 7 to the right, and the oblique teeth 8 on the left side are inserted into the sand bed 7 to the left.

[0037] Specifically, Figure 2 and Figure 3As shown, the main function of the oblique teeth 8 is to increase the friction between the bottom plate 202 and the sand bed 7, further preventing the protective shell 2 from moving under the action of the seabed current. The embedding effect of the oblique teeth 8 can significantly improve the stability of the protective shell 2 on the sand bed 7. A number of oblique teeth 8 are provided on the bottom surface of the bottom plate 202. These oblique teeth 8 are separated by the center point of the bottom plate 202. The oblique teeth 8 on both sides of the center point are in opposite directions. Specifically, the oblique teeth 8 on the right side of the center point are tilted to the right and inserted into the sand bed 7, while the oblique teeth 8 on the left side are tilted to the left and inserted into the sand bed 7. This design ensures that no matter what the direction of the seabed current is, the oblique teeth 8 can provide effective resistance to prevent the movement of the protective shell 2. The design of the oblique teeth 8 significantly improves the stability of the protective shell 2 on the sand bed 7. Through the close contact and embedding effect of the oblique teeth 8 and the sand bed 7, the impact of the seabed current can be effectively resisted. Since the oblique teeth 8 are in opposite directions and evenly distributed, this design enables the protective shell 2 to adapt to seabed currents of different directions and intensities. No matter how the current changes, the oblique teeth 8 can provide stable support and resistance.

[0038] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. According to the technical essence of the present invention, within the spirit and principles of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A delivery pipe for a gas-liquid mixed transmission and pressurization system, comprising a delivery pipe (1) connected to an output end of a supercharger, characterized in that: The conveying pipe (1) is laid on a sand bed (7) on the seabed. A flexible protective shell (2) is provided on the outer wall of the conveying pipe (1) along its length direction. The protective shell (2) has a sealed cavity (3) inside. The cavity (3) is filled with gas. The bottom of the protective shell (2) is provided with an air port (4). The air port (4) is provided with a sealing plate (5) integrally formed with the protective shell (2). The sealing plate (5) seals the air port (4). The thickness of the sealing plate (5) is less than the thickness of the bottom wall of the protective shell (2). When the conveying pipe (1) is close to the sand bed (7), the pressure difference between the water pressure outside the protective shell (2) and the air pressure inside is greater than the threshold value of the pressure required for the sealing plate (5) to break. When the sealing plate (5) is broken, the gas in the cavity (3) is instantly ejected downward along the air port (4) and disturbs the sand below. The threshold value is greater than the air pressure in the cavity (3) and less than the water pressure when close to the sand bed (7).

2. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 1, characterized in that: The protective shells (2) are evenly distributed at intervals along the length direction of the delivery pipe (1) or wrap the entire delivery pipe (1).

3. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 1, characterized in that: The delivery pipe (1) is located in the middle of the cavity (3); a protective rubber sleeve (9) is provided on the outside of the delivery pipe (1); and the protective rubber sleeve (9) is fixedly connected to the inner wall of the protective shell (2).

4. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 3, characterized in that: A connecting plate (10) made of the same material as the protective shell (2) is fixed on the outer wall of the protective rubber sleeve (9), and the connecting plate (10) is fixedly connected to the inner wall of the protective shell (2).

5. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 1, characterized in that: The protective shell (2) is welded together by a top plate (201), a bottom plate (202) and a side plate (203); the top plate (201) is an arc-shaped plate; the bottom plate (202) is an arc-shaped plate or a straight plate; the air port (4) is opened on the bottom plate (202) and is located on both sides of the delivery pipe (1); the thickness of the sealing plate (5) is smaller than the thickness of the bottom plate (202); the length direction of the protective shell (2) is perpendicular to the length direction of the delivery pipe (1); the delivery pipe (1) passes through the side plate (203); and the side plate (203) is sealed and connected to the outer wall of the delivery pipe (1).

6. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 5, characterized in that: A plurality of groups of support members for maintaining space in the cavity (3) are arranged in the cavity (3); one end of the support member is fixedly connected to the bottom surface of the top plate (201), and the other end is fixedly connected to the top surface of the bottom plate (202).

7. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 6, characterized in that: The support member is composed of two flexible reinforcing rods (6), the two reinforcing rods (6) are intersected with each other, and the two ends of the reinforcing rods (6) are respectively connected to the bottom surface of the top plate (201) and the top surface of the bottom plate (202).

8. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 1, characterized in that: After the gas in the cavity (3) is ejected, the protective shell (2) together with the delivery pipe (1) falls onto the sand bed (7) under the action of its own weight, and seawater enters the cavity (3) through the gas port (4) until the cavity (3) is filled with seawater.

9. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 5, characterized in that: The bottom surface of the bottom plate (202) is provided with a plurality of oblique teeth (8), with the center point of the bottom plate (202) serving as a dividing point, and the oblique teeth (8) on both sides of the center point are in opposite directions.

10. The delivery pipe for a gas-liquid mixed delivery and pressurization system according to claim 9, characterized in that: The oblique teeth (8) on the right side of the center point are inserted into the sand bed (7) toward the right, and the oblique teeth (8) on the left side are inserted into the sand bed (7) toward the left.

Images