Spheroidal graphite cast iron jacking pipe for internal action type integral trenchless pipeline construction

Abstract

The invention relates to the field of marine pipeline engineering, in particular to a nodular cast iron jacking pipe for internal action type integral trenchless pipeline construction, which comprises a nodular cast iron jacking pipe and a control end, and is characterized in that a birdmouth and an inserting end are integrally formed on two sides of the nodular cast iron jacking pipe; a first pressure sensing end and a second pressure sensing end are arranged on the inner wall of the birdmouth, a sliding material discharging opening is formed in the top of the nodular cast iron jacking pipe and the surface of the nodular cast iron jacking pipe, and a metal mounting strip is mounted on the outer surface of the nodular cast iron jacking pipe in an embedded mode; and a third pressure sensing end and a fourth pressure sensing end are arranged at the two ends of the surface of the metal mounting strip. By monitoring the pressure change of the outer wall of the pipeline and the seepage state of the sliding material in real time, the injection amount of the sliding material is dynamically regulated and controlled to adapt to seawater pressure fluctuation and seabed geological change; and meanwhile, the pipeline breaking risk is calculated through multi-dimensional stress analysis, a construction middle layer is accurately set, and the problem of pipeline continuous laying in the deep sea environment is solved.

Description

Technical Field

[0001] The present invention relates to the field of marine pipeline engineering, and specifically to a ductile iron pipe jacking for in-situ integral trenchless pipeline construction with internal action. Background Art

[0002] Marine pipeline engineering is mainly applied to the laying of submarine pipelines. Compared with land construction, the marine environment faces challenges such as seawater high-pressure corrosion, ocean current impact, and complex seabed geology. Traditional marine pipelines need to be laid in sections and intermediate support layers are frequently set, resulting in three major problems: Poor continuity: In the deep-sea high-pressure environment, the axial thrust of the pipeline increases exponentially with the increase of length. In order to avoid the risk of pipe body rupture in the prior art, the laying distance of each section is conservatively set not to exceed 30 meters (modified from the original 40 meters to the value for the marine scenario). Frequent start-stop of construction significantly increases the cost; Failure of slip material control: The single-point slip material discharge port is difficult to form a stable mud jacket in dynamic seawater. Continuous over-injection leads to material waste, while insufficient injection exacerbates the friction between the pipe wall and the seabed; Corrosion risk: Conventional sensors are prone to failure in the salt corrosion environment and cannot real-time monitor the stress state of the pipeline.

[0003] Therefore, there is an urgent need for an intelligent ductile iron pipe jacking suitable for the marine environment. Summary of the Invention

[0004] In order to solve the main problems of the above-mentioned traditional ductile iron pipe jacking, that is, the problem that it cannot be continuously installed and the amount of slip material cannot be controlled, the present invention solves the above problems by collecting and real-time analyzing data during the installation process of the ductile iron pipe jacking through multiple sensors.

[0005] The technical solution adopted by the present invention is: A ductile iron pipe jacking for in-situ integral trenchless pipeline construction with internal action, including a ductile iron pipe jacking, and further including a control end. Both sides of the ductile iron pipe jacking are integrally formed with a socket and a spigot end. The inner wall of the socket is provided with a first pressure sensing end and a second pressure sensing end. On the top of the ductile iron pipe jacking, a slip material discharge port is opened on the surface of the ductile iron pipe jacking. A metal installation strip is inlaid and installed on the outer surface of the ductile iron pipe jacking. Third pressure sensing ends and fourth pressure sensing ends are provided at both ends of the surface of the metal installation strip; The socket and the spigot end are mutually adapted. The set positions of the first pressure sensing end and the second pressure sensing end are at both ends of the cross-sectional diameter of the socket. The metal installation strip is in a state of being completely inlaid in the surface of the ductile iron pipe jacking. The metal installation strip, the third pressure sensing ends and the fourth pressure sensing ends are horizontal with the surface of the ductile iron pipe jacking.

[0006] Preferably, the first pressure sensing end and the second pressure sensing end are used to collect the pressure values generated by the spigot end on the socket, which are respectively denoted as p1 and p2.

[0007] Preferably, the pressure values on the outer wall of the ductile iron jacking pipe 1 collected by the third pressure sensing end and the fourth pressure sensing end are respectively denoted as p3 and P4.

[0008] Preferably, the control end includes a collection end and a processing end. The collection end includes a pressure collection unit, a time collection unit, and a speed collection unit. The pressure collection unit includes a first pressure sensing end, a second pressure sensing end, a third pressure sensing end, and a fourth pressure sensing end. The time collection unit is used to collect the displacement time of the ductile iron jacking pipe and the spraying time of the lubricant at the lubricant discharge port. The speed collection unit is the spraying speed of the lubricant at the lubricant discharge port and the moving speed of the ductile iron jacking pipe.

[0009] Preferably, the processing end is used to calculate the crushing risk coefficient of a single ductile iron jacking pipe.

[0010] Preferably, the calculation process of the crushing risk coefficient of the ductile iron jacking pipe is as follows. The crushing risk coefficient of the ductile iron jacking pipe is determined by the ratio of the maximum working stress to the material strength. The material strength is an existing parameter, and the maximum working stress is determined by any one of the maximum values of the axial stress, radial stress, and circumferential stress of the ductile iron jacking pipe. The axial stress of the ductile iron jacking pipe is: , where A is the cross-sectional area of the ductile iron jacking pipe 1. The circumferential stress of the ductile iron jacking pipe is: , where S is the surface area of 1, T is the average thickness of the ductile iron jacking pipe, and the radial stress of the ductile iron jacking pipe is the average value of p1 and p2.

[0011] Preferably, the processing end calculates the crushing risk coefficient and outputs it to the control end. When the control end determines that the crushing risk coefficient is greater than the set value, the construction is stopped and information is output to the user end.

[0012] Preferably, the user end sets a new intermediate layer with the total installation distance of the installed ductile iron jacking pipes 1 as the length.

[0013] The technical effects of the present invention are as follows: Precise regulation of lubricant: By using the pressure sensing end to monitor the frictional resistance of the seabed on the pipe wall and the seepage speed of the lubricant (newly added seawater penetration variable) in real time, and dynamically adjusting the lubricant injection amount, the problem of uncontrollable formation state of the mud jacket in the ocean current environment is solved; Deep-sea continuous construction: Based on a multi-dimensional crushing risk model of axial stress, circumferential stress, and radial stress, accurately calculate the bearing limit of the end pipeline in high-pressure seawater; Marine environment adaptability: Corrosion-resistant metal installation strips and sealed pressure sensing ends ensure the long-term stability of the sensor in a 10 MPa high-pressure seawater environment, and avoid marine pollution accidents caused by pipe body rupture through real-time risk warning. Description of the Drawings

[0014] Figure 1 It is a schematic structural diagram of any ductile iron jacking pipe of the present invention; Figure 2 It is a connection diagram of multiple ductile iron jacking pipes of the present invention; Figure 3 It is a control block diagram of the present invention. Drawings

[0015] 1. Ductile iron jacking pipe; 2. Socket joint; 21. First pressure sensing end; 22. Second pressure sensing end; 3. Insertion end; 4. Lubricant discharge port; 5. Metal installation strip; 51. Third pressure sensing end; 52. Fourth pressure sensing end. Detailed Embodiments

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Embodiment

[0017] Reference Figures 1 - 3 , an internally actuated integral trenchless pipeline construction ductile iron jacking pipe, including a ductile iron jacking pipe 1 and a control end. Socket joints 2 and insertion ends 3 are integrally formed on both sides of the ductile iron jacking pipe 1. First pressure sensing ends 21 and second pressure sensing ends 22 are provided on the inner wall of the socket joint 2. On the top of the ductile iron jacking pipe 1, a lubricant discharge port 4 is opened on the surface of the ductile iron jacking pipe 1. A metal installation strip 5 is inlaid and installed on the outer surface of the ductile iron jacking pipe 1. Third pressure sensing ends 51 and fourth pressure sensing ends 52 are provided at both ends of the surface of the metal installation strip 5; The socket joint 2 and the insertion end 3 are mutually adapted. The set positions of the first pressure sensing end 21 and the second pressure sensing end 22 are at both ends of the cross-sectional diameter of the socket joint 2. The metal installation strip 5 is in a state of being completely inlaid in the surface of the ductile iron jacking pipe 1. The metal installation strip 5 and the third pressure sensing end 51 and the fourth pressure sensing end 52 are horizontal with the surface of the ductile iron jacking pipe 1.

[0018] The first pressure sensing end 21 and the second pressure sensing end 22 are used to collect the pressure values generated by the insertion end 3 on the socket joint 2, denoted as p1 and p2 respectively; The third pressure sensing end 51 and the fourth pressure sensing end 52 are used to collect the pressure values received by the outer wall of the ductile iron jacking pipe 1, denoted as p3 and P4 respectively; It should be further noted in this embodiment that the first pressure sensing end 21, the second pressure sensing end 22, the third pressure sensing end 51, and the fourth pressure sensing end 52 are all pressure sensors. A resin protective layer is provided on the outer surfaces of the third pressure sensing end 51 and the fourth pressure sensing end 52. In addition, the length of the metal mounting strip 5 is set to be not less than 20 cm to avoid the problem of too high similarity of the parameters collected by the third pressure sensing end 51 and the fourth pressure sensing end 52 in a single area. The pressure values collected by the first pressure sensing end 21 and the second pressure sensing end 22 do not consider the data in the initial 5-second time period to avoid the problem of the influence of the additional pressure data generated by the inertia of the initial connection state on the collected data.

[0019] The control end includes a collection end and a processing end. The collection end includes a pressure collection unit, a time collection unit, and a speed collection unit. The pressure collection unit includes the first pressure sensing end 21, the second pressure sensing end 22, the third pressure sensing end 51, and the fourth pressure sensing end 52. The time collection unit is used to collect the displacement time of the ductile iron jacking pipe 1 and the spraying time of the lubricant at the lubricant discharge port 4. The speed collection unit is the spraying speed of the lubricant at the lubricant discharge port 4 and the moving speed of the ductile iron jacking pipe 1. It should be further noted that if the speed deviation of the ductile iron jacking pipe 1 per unit time is less than 0.1 m / s, it means that the spraying amount of the lubricant has minimized the friction force to the greatest extent. Otherwise, since the thrust received by the ductile iron jacking pipe 1 is constant, the moving speed of the ductile iron jacking pipe 1 cannot approach a uniform state. It should be optimized and explained in this embodiment that the unit time is set to 1 - 5 seconds. The first pressure sensing end 21, the second pressure sensing end 22, the third pressure sensing end 51, and the fourth pressure sensing end 52 transmit data at intervals of 1 ms. That is, the speed parameter collected within the unit time is the average value of the data collected by the first pressure sensing end 21, the second pressure sensing end 22, the third pressure sensing end 51, and the fourth pressure sensing end 52 after removing the maximum and minimum values, which maximally avoids the contingency of the data.

[0020] The processing end is used to calculate the fracture risk coefficient of a single ductile iron jacking pipe 1. The specific calculation process is as follows: The fracture risk coefficient of the ductile iron jacking pipe 1 is determined by the ratio of the maximum working stress to the material strength. The material strength is an existing parameter, and the maximum working stress is determined by any one of the maximum values of the axial stress, radial stress, and circumferential stress of the ductile iron jacking pipe 1. The axial stress of the ductile iron jacking pipe 1 is: , where A is the cross-sectional area of the ductile iron jacking pipe 1. The circumferential stress of the ductile iron jacking pipe 1 is: , where S is the surface area of 1, T is the average thickness of the ductile iron jacking pipe 1, and the radial stress of the ductile iron jacking pipe 1 is defaulted to the average value of p1 and p2; It should be further noted in this embodiment that by measuring the fracture risk coefficient of the endmost ductile iron jacking pipe 1, when the fracture risk coefficient is 1, it is default that the ductile iron jacking pipe 1 will surely fracture. Therefore, the theoretical safety threshold is set to 0.5. In addition, when the fracture risk coefficients of multiple unit time periods of any other ductile iron jacking pipe 1 are greater than 0.5, the construction will be stopped and sampling inspection will be carried out at the modified position to ensure that there will be no local pipe damage caused by special terrain or installation defects; It should also be further noted that when the fracture risk coefficient of the endmost ductile iron jacking pipe 1 is greater than 0.5, a new intermediate layer will be set with the sum of the installation distances of multiple ductile iron jacking pipes 1 as the length; Working principle: Preparation stage: Lay the guide rails, set up the mirror wall and the reaction wall. The jacking system and the positioning system are set at the position of the reaction wall. Then set up the lubricant injection system. Finally, place the ductile iron jacking pipe 1 on the guide rails corresponding to the jacking system; All the equipment involved in the above-mentioned preparation stage that needs to be specifically described are conventional preparation equipment, so they will not be specifically described in this embodiment; Jacking stage: Lubricant output stage: The jacking system pushes the ductile iron jacking pipe 1 through the mirror wall and into the seabed. At the same time, start the lubricant injection system. At this time, the lubricant is discharged along the lubricant discharge port 4. In this stage, the number of ductile iron jacking pipes 1 is more than two, and the insertion end 3 is located in the socket 2 inside the front ductile iron jacking pipe 1. At this time, the first pressure sensing end 21 and the second pressure sensing end 22 collect the pressure values generated by the insertion end 3 on the socket 2. The third pressure sensing end 51 and the fourth pressure sensing end 52 are used to collect the pressure values received by the outer wall of the ductile iron jacking pipe 1. In addition, the time acquisition unit is used to collect the displacement time of the ductile iron jacking pipe 1 and the lubricant spraying time at the lubricant discharge port 4. The speed acquisition unit is the spraying speed of the lubricant at the lubricant discharge port 4 and the moving speed of the ductile iron jacking pipe 1. If the moving speed of the ductile iron jacking pipe 1 is in a uniform state per unit time, the lubricant injection system will keep feeding at a uniform speed. If the moving speed of the ductile iron jacking pipe 1 shows an obvious deceleration, the feeding amount will be increased until the moving speed area of the ductile iron jacking pipe 1 is uniform. At this time, the feeding speed of the lubricant injection system will be reduced to the previous stage. If the moving speed of the ductile iron jacking pipe 1 shows an obvious deceleration, the lubricant injection system will perform secondary acceleration and will not be adjusted back. Thus, the preliminary jacking stage is completed; Continuous advancing stage: The jacking system will increase the thrust according to the increase in the number of ductile iron jacking pipes 1. The first ductile iron jacking pipe 1 entering the ground is under the greatest stress. Therefore, the data collection is mainly based on the last one, and the ductile iron jacking pipes 1 at other positions are only used for differential data analysis. At this time, according to the pressure data collected by the ductile iron jacking pipe 1, the risk coefficient of the ductile iron jacking pipe 1 is obtained. When the risk coefficient of the ductile iron jacking pipe 1 is greater than the threshold, the jacking is stopped and a new intermediate layer is set. Finally, it is possible to accurately judge whether to set the intermediate layer and avoid over-construction. Embodiment

[0021] The specific difference between Embodiment 1 and Embodiment 2 is that the crushing risk coefficient of the ductile iron jacking pipe 1 is determined by the ratio of the maximum working stress to the material strength. The material strength is an existing parameter, and the maximum working stress is determined by any minimum value of the axial, radial and circumferential stresses of the ductile iron jacking pipe 1. The axial stress of the ductile iron jacking pipe 1 is: , where A is the cross-sectional area of the ductile iron jacking pipe 1. The circumferential stress of the ductile iron jacking pipe 1 is: , where S is the surface area of 1, and T is the average thickness of the ductile iron jacking pipe 1. The radial stress of the ductile iron jacking pipe 1 is defaulted to the mean value of p1 and p2; The calculated crushing risk coefficient of the ductile iron jacking pipe 1 in Embodiment 2 is more conservative compared to Embodiment 1, and it is applied to some areas with diverse geological layers for the environment.

[0022] The above content is only an example and explanation of the structure of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, as long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should fall within the protection scope of the present invention.

Claims

1. A ductile iron pipe jacking for trenchless pipeline construction with internal action as a whole, including a ductile iron pipe jacking (1), characterized in that, It also includes a control end. On both sides of the ductile iron jacking pipe (1), a socket (2) and a spigot end (3) are integrally formed. On the inner wall of the socket (2), a first pressure sensing end (21) and a second pressure sensing end (22) are provided. On the top of the ductile iron jacking pipe (1), a lubricant discharge port (4) is formed on the surface of the ductile iron jacking pipe (1). A metal mounting strip (5) is inlaid on the outer surface of the ductile iron jacking pipe (1). At both ends of the surface of the metal mounting strip (5), a third pressure sensing end (51) and a fourth pressure sensing end (52) are provided; The socket (2) and the spigot end (3) are mutually adapted. The set positions of the first pressure sensing end (21) and the second pressure sensing end (22) are at both ends of the cross-sectional diameter of the socket (2). The metal mounting strip (5) is in a state of being completely inlaid in the surface of the ductile iron jacking pipe (1). The metal mounting strip (5), the third pressure sensing end (51) and the fourth pressure sensing end (52) are horizontal with the surface of the ductile iron jacking pipe (1).

2. A ductile iron pipe jacking for trenchless pipeline construction with internal action as claimed in claim 1, wherein, The first pressure sensing end (21) and the second pressure sensing end (22) are used to collect the pressure values generated by the spigot end (3) on the socket (2), denoted as p1 and p2 respectively.

3. A ductile iron pipe jacking for trenchless pipeline construction with internal action as claimed in claim 1, characterized in that, The third pressure sensing end (51) and the fourth pressure sensing end (52) are used to collect the pressure values received by the outer wall of the ductile iron jacking pipe (1), denoted as p3 and P4 respectively.

4. A ductile iron jacking pipe for internal-acting integral trenchless pipeline construction according to claim 1, characterized in that, The control end includes a collection end and a processing end. The collection end includes a pressure collection unit, a time collection unit and a speed collection unit. The pressure collection unit includes the first pressure sensing end (21), the second pressure sensing end (22), the third pressure sensing end (51) and the fourth pressure sensing end (52). The time collection unit is used to collect the displacement time of the ductile iron jacking pipe (1) and the lubricant spraying time at the lubricant discharge port (4). The speed collection unit is the spraying speed of the lubricant at the lubricant discharge port (4) and the moving speed of the ductile iron jacking pipe (1).

5. A ductile iron pipe jacking for trenchless pipeline construction with internal action as claimed in claim 4, characterized in that, The processing end is used to calculate the fracture risk coefficient of a single ductile iron jacking pipe (1).

6. A ductile iron pipe jacking for trenchless pipeline construction with internal action as claimed in claim 5, characterized in that, The calculation process of the crushing risk coefficient of the ductile iron jacking pipe (1) is as follows. The crushing risk coefficient of the ductile iron jacking pipe (1) is determined by the ratio of the maximum working stress to the material strength. The material strength is an existing parameter, and the maximum working stress is determined by any one of the axial, radial, and circumferential stresses of the ductile iron jacking pipe (1). The axial stress of the ductile iron jacking pipe (1) is: , where A is the cross-sectional area of the ductile iron jacking pipe (1). The circumferential stress of the ductile iron jacking pipe (1) is: , where S is the surface area of 1, and T is the average thickness of the ductile iron jacking pipe (1). The radial stress of the ductile iron jacking pipe (1) is the mean value of p1 and p2.

7. A ductile iron pipe jacking for trenchless pipeline construction with internal action as claimed in claim 4, characterized in that, The processing end calculates the fracture risk coefficient and outputs it to the control end. When the control end determines that the fracture risk coefficient is greater than the set value, the construction is stopped and information is output to the user end.

8. A ductile iron pipe jacking for trenchless pipeline construction with internal action as claimed in claim 5, characterized in that, The user end sets a new intermediate layer with the total installation distance of the installed ductile iron jacking pipes (1) as the length.

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