Method for water connection of over-river pipe and floating box device

Abstract

The application discloses a method for over-river pipe water connection and a floating box device in the technical field of over-river pipe construction, and comprises a box body, both ends of the box body along the axial direction are provided with openings for inserting the to-be-connected pipe, a sealing structure is arranged on the periphery of the opening, the box body is provided with an openable and closable sealing window and a submersible pump, and the water inlet of the submersible pump is communicated with the space in the box body. Through optimization of the box body structure, integration of the sealing and positioning functions and simplification of the transportation and assembly process, the problems of water flow interference, poor weld quality, low positioning accuracy, weak adaptability and inconvenient transportation of the over-river pipe water connection welding are solved, the effective of the connection edge amount is realized, and the one-time qualified rate of the weld is improved. The device and the method shorten the connection period, reduce the construction cost and the safety risk, and are suitable for the connection of over-river pipes with different diameters.

Description

Technical Field

[0001] This invention relates to the field of river-crossing pipeline construction technology, and in particular to a method for waterborne docking of river-crossing pipelines and a floating box device. Background Technology

[0002] Cross-river pipelines are core facilities for water and gas transmission across waterways, and the quality of segmented welding directly affects the safety and service life of the project. In existing technologies, underwater welding or open-air welding is mostly used for connecting cross-river pipelines over water. Underwater welding is affected by water flow and waves, and the weld is prone to defects such as porosity and incomplete fusion, resulting in a low first-pass yield and difficulty in controlling misalignment. Open-air welding lacks effective water-proofing measures, and rainwater flow can easily corrode the weld, reducing its corrosion resistance. Summary of the Invention

[0003] To overcome its shortcomings, the technical problem to be solved by this invention is: how to improve the welding quality during the segmented docking process of existing river-crossing pipelines.

[0004] The technical solution adopted by this invention to solve its technical problem is: The floating box device for docking river-crossing pipelines includes a box body, with openings at both ends along the axial direction for inserting the pipeline to be docked; a sealing structure is provided around the openings; the box body is equipped with an openable and closable sealing window and a submersible pump, with the inlet of the submersible pump connected to the internal space of the box body.

[0005] Furthermore, the box body is cylindrical in shape, and the two openings are coaxially arranged with the box body. Multiple lifting lug structures are evenly spaced along the circumference of the outer wall of the box body. The multiple lifting lug structures are used to install ground anchors and drive ropes.

[0006] Furthermore, the sealing structure includes a rubber sealing layer disposed on the inner wall of the opening, and a pressure plate is provided in the housing to press the rubber sealing layer tightly against the inner wall of the opening.

[0007] Furthermore, the inner wall of the box is provided with multiple adjustable limiting structures for abutting the connecting pipes; the adjustable limiting structure includes a support block and a threaded rod, the support block is provided with a threaded hole that mates with the threaded rod, and the abutting end of the threaded rod is provided with a rubber abutting layer.

[0008] Furthermore, the inner wall of the enclosure is provided with multiple reinforcing ribs, which simultaneously connect the inner walls of the end plates and the inner walls of the side plates of the enclosure.

[0009] This application also proposes a method for waterborne connection of cross-river pipelines, including the following steps: S1: Fabricate a floating box device of the corresponding size according to the pipeline to be connected; S2: Install blind flanges at both ends of the pipe to be docked, lift the two sections of the pipe to be docked with blind flanges using airbags and launch them into the water with the help of a floating crane, and then tow them to the docking area by an anchor boat. After adjusting their attitude, place ground anchors to fix them in place. S3: Anchoring structures are pre-installed in the docking water area; S4: Hoist the floating box device to the docking water area, insert the two sections of pipe to be docked into the two openings of the box respectively, remove the blind plate at the docking end of the pipe to be docked, and fix the box through the anchoring structure; S5: Start the submersible pump to drain the water from the tank. After draining the water from the tank, check the airtightness of the space inside the tank. S6: The operator enters the enclosure through the operating window to weld the joint between the two pipes to be connected; S7: After the welding is completed and cooled, the weld is inspected for non-destructive testing and found to be qualified; the operator exits the box through the sealed window and fills the box with water to make it sink, and the floating crane lifts the box away to complete the docking operation; S8: Use a total station to check the deviation of the pipe section's axis and elevation; if the deviation exceeds the standard, make fine adjustments by adjusting the ground anchor cables at both ends of the pipe section, and complete the construction after verification.

[0010] Furthermore, the manufacturing method of the floating box device in step S1 includes: manufacturing a cylindrical box body by submerged arc welding according to the docking pipeline design; welding reinforcing ribs inside the box body, the reinforcing ribs connecting the inner wall of the end plate and the inner wall of the arc-shaped side plate of the box body; installing a rubber sealing layer and a pressure plate, and fastening the rubber sealing layer and the pressure plate with bolts; welding a submersible pump bracket, fixing the submersible pump and connecting the drainage pipe; and welding a lifting eye plate structure on the outer wall of the box body.

[0011] Furthermore, the process also includes enclosure inspection and painting: filling the enclosure with water to full capacity, soaking for a preset time, and checking whether the leakage meets the requirements; performing non-destructive testing on the welds to ensure there are no defects such as cracks or incomplete penetration; removing rust from the inner wall of the enclosure and the surface of the replacement ear plates, and applying epoxy zinc-rich primer; and applying an additional chlorosulfonated polyethylene topcoat to the outer wall of the enclosure.

[0012] Furthermore, in step S2, after the two pipes to be docked are launched into the water, cables are connected to both ends of the pipes to be docked, and the other end of the cables is connected to the anchor boat. The floating speed of the pipe section is controlled to be ≤1m / s throughout the process to prevent the pipe section from drifting under the action of water flow. After the pipes to be docked are floated to the docking area, the pipe section is temporarily fixed by ground anchor cables to ensure that the axes of the two pipes to be docked coincide and are consistent with the docking direction.

[0013] Furthermore, in step S6, the operator enters the box through the sealed window and adopts a three-stage welding process of root pass + fill pass + cover pass; the root pass is done by manual arc welding, starting from the bottom of the pipe to be connected and working upwards, with a current of 90-110A; the fill pass welding current is 120-140A, and the interpass temperature is controlled not to exceed 150℃; the cover pass welding current is 110-130A, the weld reinforcement is 2-3mm, and the width is 2-4mm wider than the bevel; the sealed window is opened during the welding process.

[0014] The beneficial effects of this invention are: By optimizing the box structure, integrating sealing and positioning functions, and simplifying the transportation and assembly process, this invention solves the problems of water flow interference, poor weld quality, low positioning accuracy, weak adaptability, and inconvenient transportation in the underwater docking welding of cross-river pipes. It effectively reduces the misalignment of the docking edges and improves the first-pass yield of the weld. The device and method proposed in this application shorten the docking period, reduce construction costs and safety risks, and are adaptable to docking of cross-river pipes of different diameters. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the floating box device structure in this invention; The markings in the diagram are: 1-box body, 2-sealed window, 3-opening, 4-reinforcing rib, 5-sealing structure, 6-adjustable limiting structure, 7-submersible pump, 8-lifting eye plate structure. Detailed Implementation

[0016] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0017] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this disclosure.

[0018] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0019] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0020] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0021] 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 discussed further in subsequent figures.

[0022] The invention will be further described below with reference to the accompanying drawings.

[0023] like Figure 1 As shown, this application proposes a floating box device for underwater docking of cross-river pipes, including a box body 1. Both ends of the box body 1 along its axial direction are provided with openings 3 for inserting the pipes to be docked. A sealing structure 5 is provided around the openings 3. The box body 1 is equipped with an openable sealing window 2 and a submersible pump 7. The inlet of the submersible pump 7 connects to the internal space of the box body 1, and the sealing window 2 is located at the upper part of the box body 1. The two sections of pipes to be docked are respectively connected to the openings 3 at both ends of the box body 1. The sealing structure 5 seals the connection seam, allowing the box body 1 and the two pipes to be docked to seal the interior of the box body 1 into a sealed cavity structure. The submersible pump 7 is connected within the sealed cavity, allowing water entering the box body 1 to be drained, ensuring that the subsequent welding process is not constrained by the aquatic environment and improving welding quality.

[0024] The aforementioned box 1 can be rectangular to achieve a floating structure. However, to accommodate cylindrical pipes and reduce material consumption, box 1 is cylindrical, with two openings 3 coaxially aligned with it. Multiple lifting ring lug structures 8 are evenly spaced along the circumference of the outer wall of box 1. These lug structures 8 are used to set anchors and drive ropes, enabling the driving and position adjustment of box 1 in water, thus improving work efficiency. To further enhance the structural strength of box 1, multiple reinforcing ribs 4 are provided on the inner wall of box 1, connecting both the inner walls of the end plates and the side plates. The lifting ring lug mechanism includes multiple lifting rings located on the upper part of box 1 for lifting equipment to lower box 1 into the water. It also includes multiple lugs evenly distributed around the perimeter of box 1 for adjusting the attitude of box 1 in water using a driving mechanism such as an anchor boat or a hand-operated hoist.

[0025] The cylindrical box 1 has coaxial cylindrical openings 3 at both ends to accommodate the shape of a typical cylindrical pipe. The outer diameter of the box 1 is larger than the inner diameter of the opening 3, allowing for the opening of a sealed window 2 on the annular structural wall at both ends of the box 1 and the internal working cavity, facilitating operator access to the box 1. In addition, the internal working cavity is a relatively sealed cavity formed after the pipes to be connected at both ends are adjusted and connected. It is formed by the joint sealing of the outer wall of the pipes to be connected and the inner wall of the box 1. A submersible pump 7 is introduced into the internal working cavity to remove the water inside, facilitating welding operations and ensuring a better welding environment.

[0026] To improve the sealing of the internal working chamber, a sealing structure 5 is provided around the opening 3. The sealing structure 5 can be a sealing gasket fixed to the inner wall of the opening 3. However, to further improve stability, the sealing structure 5 includes a rubber sealing layer set on the inner wall of the opening 3. The box body 1 is provided with a pressure plate, which presses the rubber sealing layer tightly against the inner wall of the opening 3. This structure can prevent the rubber sealing layer from shifting or falling off when the pipe is pushed in.

[0027] In actual operation, after the pipe to be connected to opening 3 is aligned, it may shake or shift. It is necessary to continuously adjust and check during the welding process. In order to improve construction efficiency, multiple adjustable limiting structures 6 are set on the inner wall of the box 1 to abut the pipe to be connected. The adjustable limiting structure 6 includes a support block and a threaded rod. The support block has a threaded hole that fits with the threaded rod. The abutting end of the threaded rod is provided with a rubber abutting layer. That is to say, after the two sections of pipe to be connected are connected, the adjusted position of the pipe to be connected is stably supported by adjusting multiple threaded rods against the outer wall of the pipe to be connected.

[0028] This application also proposes a method for waterborne connection of cross-river pipelines, including the following steps: S1: Fabricate a box body 1 device of corresponding size according to the pipeline to be connected; the fabrication method of the box body 1 device includes: fabricating a cylindrical box body 1 by submerged arc welding according to the design of the pipeline to be connected; welding reinforcing ribs 4 inside the box body 1, the reinforcing ribs 4 connecting the inner wall of the end plate and the inner wall of the arc-shaped side plate of the box body 1; installing a rubber sealing layer and a pressure plate, and fastening the rubber sealing layer and the pressure plate with bolts; welding a bracket for the submersible pump 7, fixing the submersible pump 7 and connecting the drainage pipe; welding a lifting eye plate structure 8 on the outer wall of the box body 1.

[0029] In addition, the process includes the inspection and painting of enclosure 1. The inspection of enclosure 1 includes: filling enclosure 1 with water to full capacity, immersing it for a preset time, and checking for leaks. Specifically, this includes: conducting a watertightness test after welding, immersing it in water for 24 hours, and ensuring a leakage rate of no more than 0.5 liters per hour; and ensuring the sealing effect of enclosure 1 through a sealing test. Non-destructive testing is performed on the welds to ensure there are no cracks or incomplete penetration defects. The inspection process for enclosure 1 mainly focuses on its sealing and connection strength to ensure stability and safety during operation.

[0030] The painting process includes: rust removal and application of epoxy zinc-rich primer to the inner wall of tank 1 and the surface of the replacement ear plates; additional application of chlorosulfonated polyethylene topcoat to the outer wall of tank 1; painting can improve the corrosion resistance of tank 1 in water and enhance its durability. The dry film thickness of the paint should be no less than 200 micrometers, with no wrinkling or peeling.

[0031] S2: Install blind flanges at both ends of the pipeline to be docked. Use airbags to lift the two sections of the pipeline to be docked, and then launch them into the water with the help of a floating crane. Anchor boats will then tow them to the docking area, adjust their attitude, and finally deploy ground anchors for fixation. The specific process includes: prefabricating the sections of the pipeline to be docked on shore; sealing both ends of the pipeline with blind flanges and welding reinforcing ribs 4; sealing with blind flanges helps the pipeline float, facilitating transportation; after the pipeline is launched, fix it to both ends with four cables, with the other end of the cables connected to the anchor boat. Maintain the floating speed of the pipeline throughout the process to ≤1m / s, preventing it from drifting under the influence of water currents; after floating to the docking area, temporarily fix the pipeline to be docked with ground anchor cables to ensure that the axis of the pipeline is aligned with the docking direction.

[0032] S3: Pre-set anchoring structures in the docking water area; first, lay 4 ground anchors around the docking water area (riverbed burial depth ≥ 1.5m or fixed with ballast) to form stable force support points.

[0033] S4: Hoist the container 1 to the docking area, insert the two sections of pipe to be docked into the two openings 3 of the container 1, remove the blind flanges at the docking ends of the pipes to be docked, and fix the container 1 with the anchoring structure; the specific fixing method includes: setting 4 ear plates at each end of the container 1 evenly distributed around the circumference, connecting the ear plates to the ground anchor with steel wire ropes, leaving a 1-1.5m adjustment margin, initially tightening the steel wire ropes to fix the container 1 and fine-tuning the tension of a single steel wire rope with a hand-operated hoist, using the symmetrical force characteristics of the 8 ear plates to correct the pipe section docking deviation: adjust the steel wire ropes of the corresponding upper and lower ear plates for vertical offset, adjust the steel wire ropes of the left and right ear plates for horizontal misalignment, observe the alignment of the ports in real time until the misalignment is ≤3mm, and finally lock the steel wire ropes with clamps to complete the precise positioning; at this time, the floating crane lifts the container 1 to the docking port, and after pulling the two pipes to be docked into the two openings 3 of the container 1, fix them with the ear plates and the ground anchor, and the divers remove the blind flanges at the docking ends underwater.

[0034] S5: Start the submersible pump 7 to drain the water from the tank 1. After draining the water from the tank 1, check the airtightness of the space inside the tank 1.

[0035] S6: The operator enters the box 1 through the operation window and welds the joint of the two pipes to be connected. Generally, E4303 welding rods are used for welding, with a root pass current of 100 amps, a fill pass current of 130 amps, a cover pass current of 120 amps, and the interpass temperature controlled at 120 degrees Celsius.

[0036] S7: After the welding is completed and cooled, the weld is inspected for non-destructive testing and found to be qualified; the operator exits the box 1 through the sealed window 2 and fills the box 1 with water to make it sink. The floating crane lifts the box 1 away to complete the docking operation.

[0037] S8: Use a total station to check the axis deviation and elevation deviation of the pipe section. The axis deviation ≤5mm and the elevation deviation ≤3mm are considered qualified. If the deviation exceeds the standard, make a fine adjustment by adjusting the ground anchor cables at both ends of the pipe section. After the verification is qualified, the construction is completed.

[0038] In summary, this invention proposes a method and floating box device for underwater docking of cross-river pipes. The floating box device forms a closed, dry working space, completely isolating the pipes from water flow and waves, increasing the first-pass yield rate of welds to over 98%, and controlling the misalignment within 3 mm, meeting the quality requirements of Class II welds. Furthermore, construction efficiency is significantly improved, with the docking period for a single set of pipes being docked shortened by more than 60% compared to traditional underwater welding. By adjusting the inner diameter of the box body 1 and the opening 3, and the corresponding dimensions of the sealing structure 5, it can accommodate docking of different specifications of cross-river pipes without the need for repeated customization. The entire device and construction process avoids the risks associated with underwater welding, and the support block design prevents pipe section displacement, ensuring construction safety. The box body 1, after anti-corrosion treatment, can be reused more than 20 times, reducing resource waste and lowering construction costs.

Claims

1. A floating box device for waterborne docking of a river-crossing pipeline, characterized in that, Includes a housing (1), with openings (3) at both ends along the axial direction for inserting pipes to be connected; a sealing structure (5) is provided around the opening (3); the housing (1) is provided with an openable sealing window (2) and a submersible pump (7), the inlet of the submersible pump (7) is connected to the space inside the housing (1).

2. The floating box device for waterborne docking of the river-crossing pipeline according to claim 1, characterized in that, The box (1) is cylindrical in shape, and the two openings (3) are coaxially arranged with the box (1). Multiple lifting ring ear plate structures (8) are evenly spaced along the circumference of the outer wall of the box (1). The multiple lifting ring ear plate structures (8) are used to set the ground anchor and drive rope.

3. The floating box device for waterborne docking of the river-crossing pipeline according to claim 2, characterized in that, The sealing structure (5) includes a rubber sealing layer disposed on the inner wall of the opening (3), and the box body (1) is provided with a pressure plate, which presses the rubber sealing layer tightly against the inner wall of the opening (3).

4. The floating box device for waterborne docking of the river-crossing pipeline according to claim 1, characterized in that, The inner wall of the box (1) is provided with multiple adjustable limiting structures (6) for abutting and connecting pipes; the adjustable limiting structure (6) includes a support block and a threaded rod, the support block is provided with a threaded hole that is threaded to the threaded rod, and the abutting end of the threaded rod is provided with a rubber abutting layer.

5. The floating box device for waterborne docking of the river-crossing pipeline according to claim 1, characterized in that, Multiple reinforcing ribs (4) are provided on the inner wall of the box (1), and the reinforcing ribs (4) are connected to the inner wall of the end plate and the inner wall of the side plate of the box (1).

6. A method for waterborne connection of cross-river pipelines, characterized in that, The floating box device for waterborne docking of river-crossing pipelines as described in any one of claims 1-5 includes the following steps: S1: Fabricate a floating box device of the corresponding size according to the pipeline to be connected; S2: Install blind flanges at both ends of the pipe to be docked, lift the two sections of the pipe to be docked with blind flanges using airbags and launch them into the water with the help of a floating crane, and then tow them to the docking area by an anchor boat. After adjusting their attitude, place ground anchors to fix them in place. S3: Anchoring structures are pre-installed in the docking water area; S4: Hoist the floating box device to the docking water area, put the two sections of pipe to be docked into the two openings (3) of the box body (1) respectively, remove the blind plate at the docking end of the pipe to be docked, and fix the box body (1) through the anchoring structure; S5: Start the submersible pump (7) to drain the water in the tank (1). After draining the water from the tank (1), check the airtightness of the space inside the tank (1). S6: Operators enter the floating box through the operating window to weld the joint of the two pipes to be connected; S7: After the welding is completed and cooled, the weld is inspected for non-destructive testing and found to be qualified; the operator exits the box (1) through the sealed window (2) and fills the box (1) with water to make it sink, and the floating crane lifts the box (1) to complete the docking operation; S8: Use a total station to check the deviation of the pipe section's axis and elevation; if the deviation exceeds the standard, make fine adjustments by adjusting the ground anchor cables at both ends of the pipe section, and complete the construction after verification.

7. The method for waterborne docking of cross-river pipelines according to claim 6, characterized in that, The processing method of the floating box device in step S1 includes: making a cylindrical box (1) by submerged arc welding according to the design of the docking pipeline; welding reinforcing ribs (4) inside the box (1), the reinforcing ribs (4) connecting the inner wall of the end plate and the inner wall of the arc side plate of the box (1); installing the rubber sealing layer and the pressure plate, and fastening the rubber sealing layer and the pressure plate with bolts; welding the support of the submersible pump (7), fixing the submersible pump (7) and connecting the drainage pipe; welding the lifting ring ear plate structure (8) on the outer wall of the box (1).

8. The method for waterborne docking of cross-river pipelines according to claim 7, characterized in that, It also includes the inspection and painting process of the tank (1): fill the floating box with water to full capacity, soak for a preset time, and check whether the leakage meets the requirements; perform non-destructive testing on the weld; remove rust from the inner wall of the tank (1) and the surface of the lifting ring ear plate structure (8) and apply epoxy zinc-rich primer; apply chlorosulfonated polyethylene topcoat to the outer wall of the tank (1).

9. The method for waterborne docking of a cross-river pipeline according to claim 6, characterized in that, In step S2, after the two pipes to be docked are launched into the water, cables are connected to both ends of the pipes to be docked, and the other end of the cables is connected to the anchor boat. The floating speed of the pipe section is controlled to be ≤1m / s throughout the process to prevent the pipe section from drifting under the action of water flow. After the pipes to be docked are floated to the docking area, the pipe section is temporarily fixed by ground anchor cables to ensure that the axes of the two pipes to be docked are coincident and consistent with the docking direction.

10. The method for waterborne docking of a river-crossing pipeline according to claim 6, characterized in that, In step S6, the operator enters the box (1) through the sealed window (2) and adopts a three-stage welding process of root pass + fill pass + cover pass. The root pass is done by manual arc welding, starting from the bottom of the pipe to be connected and working upwards, with a current of 90-110A. The fill pass welding current is 120-140A, and the interpass temperature is controlled to not exceed 150℃. The cover pass welding current is 110-130A, the weld reinforcement is 2-3mm, and the width is 2-4mm wider than the bevel. The sealed window (2) is opened during the welding process.

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