Efficient welding system for single-face welding and double-face forming of subsea pipeline

Abstract

The utility model belongs to the field of pipeline welding, and particularly discloses an efficient welding system for single-side welding and double-side forming of a subsea pipeline, which comprises bottom sealing and hot welding equipment, filling and capping welding equipment and a rigid track, the bottom sealing and hot welding equipment comprises a first welding unit, the first welding unit comprises a CMT welding power source and a single-torch welding trolley, and a CMT welding gun electrically connected with the CMT welding power source is fixedly connected to the single-torch welding trolley; the rigid track is detachably mounted on the subsea pipeline, and the single-torch welding trolley is detachably mounted on the rigid track when the subsea pipeline is welded; and the filling and capping welding equipment is used for welding the subsea pipeline subjected to bottom sealing and hot welding. By means of the method, the single-face welding and double-face forming effect under the gapless assembly can be achieved under the condition that copper liners are not adopted for bottom sealing and hot welding, meanwhile, the filling efficiency is high during filling and cosmetic welding, the welding efficiency can be improved, and meanwhile the method is suitable for welding of a whole series of subsea pipelines such as common carbon steel, acid pipes and composite pipes.

Description

Technical Field

[0001] The present application belongs to the field of pipeline welding, and more specifically, relates to an efficient welding system for single-sided welding and double-sided forming of submarine pipelines. Background Art

[0002] With the development of technologies such as marine engineering and deep-sea mining, human exploration of the ocean has gradually shifted from shallow waters to deep seas. Subsea pipelines are crucial hubs for offshore oil and gas transmission, and their construction and maintenance are key technologies in the marine engineering field. The installation and repair of subsea pipelines cannot be separated from welding processes.

[0003] In the relevant technology, the welding of submarine pipelines mainly includes bottom welding and filling welding. The bottom welding methods that can achieve single-sided welding and double-sided forming generally include TIG welding, STT welding and MAG welding. However, the above welding methods usually require gap assembly of the submarine pipeline, which is complicated to operate and has high assembly difficulty. Among them, MAG welding also requires the use of copper lining on the back of the pipeline for forced forming, resulting in low submarine pipeline welding efficiency. Moreover, it can only be applied to conventional carbon steel submarine pipelines, and its application has limitations. Utility Model Content

[0004] In response to the defects of the existing technology, the present application provides an efficient welding system for single-sided welding and double-sided forming of submarine pipes, aiming to solve the problems of low welding efficiency and poor applicability of existing submarine pipes.

[0005] The present application provides an efficient welding system for single-sided welding and double-sided forming of submarine pipelines, which specifically includes bottom sealing and hot welding equipment, filling and covering welding equipment, and a rigid track. The bottom sealing and hot welding equipment and the filling and covering welding equipment are arranged in sequence along the conveying direction of the submarine pipeline; the bottom sealing and hot welding equipment includes a first welding unit, which includes a CMT welding power supply and a single-torch welding trolley, and the single-torch welding trolley is fixedly connected to a CMT welding gun electrically connected to the CMT welding power supply; the rigid track is detachably mounted on the submarine pipeline and surrounds the outer wall of the submarine pipeline. When welding the submarine pipeline, the single-torch welding trolley is detachably mounted on the rigid track to move around the submarine pipeline; the filling and covering welding equipment is used to weld the submarine pipeline after bottom sealing and hot welding by the CMT welding gun are completed.

[0006] The above technical solution conceived by the present application is applicable to different submarine pipeline welding methods compared with the prior art because the present application adopts a CMT welding power source for bottom sealing welding and hot welding. Due to the small heat input during welding, the gravity of the molten pool metal and the arc force are small, defects such as weld penetration and weld collapse are not easily generated, a smooth weld at the root is easily obtained, and the excess height control under the conditions of full-position welding of submarine pipelines is more easily achieved. Without using a copper liner, a single-sided welding and double-sided forming effect can be achieved under gapless assembly, ensuring complete fusion of the weld root, ensuring the integrity and strength of the weld, and achieving the beneficial effects of simplifying the welding steps and improving the welding efficiency.

[0007] As a further preferred embodiment, two first welding units are provided, and the two first welding units are respectively provided on both sides of the sea pipe; the first welding unit also includes a first frame for placing a CMT welding power source and a corresponding single-torch welding trolley.

[0008] By adopting the above technical solution, welding can be carried out simultaneously from both sides of the submarine pipeline, further improving welding efficiency. At the same time, the first frame is used to place the corresponding welding units and welding carriages, which greatly reduces the cable length of the welding power supply and reduces the resistance and inductance of the welding circuit, thereby ensuring the stability of the welding process.

[0009] As a further preference, the bottom sealing and heat welding equipment further comprises a first conveying frame, on which a V-shaped placement platform for placing the sea pipe and arranged horizontally is provided.

[0010] By adopting the above technical solution, the subsea pipeline can be placed horizontally in the middle of the V-shaped placement platform to facilitate welding by a single-torch welding trolley.

[0011] As a further preferred embodiment, both sides of the V-shaped placement platform are rotatably connected with conveying rollers, the rotation axis of the conveying rollers is perpendicular to the sea pipe, a directional conveying channel is formed between the two conveying rollers, and multiple groups of conveying rollers are arranged along the opening direction of the V-shaped placement platform.

[0012] By adopting the above technical solution, after the bottom sealing and heat welding of the submarine pipe are completed on the first conveying rack, the submarine pipe can be moved in the V-shaped placement platform through the conveying rollers to facilitate the transfer of the submarine pipe for subsequent welding operations.

[0013] As a further preferred embodiment, the filling and cover welding equipment includes a second welding unit, which includes a pulse welding power supply and a dual-torch welding trolley. Two welding guns electrically connected to the pulse welding power supply are fixedly connected to the dual-torch welding trolley. When welding the subsea pipe, the dual-torch welding trolley can be detachably mounted on the rigid track to move around the subsea pipe, and both welding guns of the dual-torch welding trolley are facing the subsea pipe.

[0014] By adopting the above technical solution, a dual-torch welding trolley is used to weld the subsea pipeline, thereby further improving the welding efficiency. At the same time, filler metal is used to eliminate the unfused defects, and the final appearance of the weld is formed by cap welding.

[0015] As a further preference, the distance between the two welding guns of the dual-torch welding carriage is 50 mm to 100 mm.

[0016] By adopting the above technical solution, welding can be carried out effectively. When the gun distance is less than 50mm, the two arcs of the dual torches interfere with each other seriously, and stable weld formation cannot be achieved. When the gun distance is greater than 100mm, although there is no interference between the arcs, it is not suitable for efficient welding of 10-inch and smaller submarine pipelines.

[0017] As a further preference, each of the two welding guns of the dual-torch welding carriage is connected to a pulse welding power supply.

[0018] By adopting the above technical solution, two pulse welding power supplies respectively control the two welding guns of the dual-torch welding trolley, so that the dual-torch welding trolley also has the single-torch welding function.

[0019] As a further preference, two second welding units are provided, and the two second welding units are respectively arranged on both sides of the sea pipe; the second welding unit also includes a second frame for placing a pulse welding power supply and a double-torch welding trolley.

[0020] By adopting the above technical solution, welding can be carried out simultaneously from both sides of the submarine pipeline, thereby improving welding efficiency. At the same time, the second frame is used to place the corresponding welding units and welding carriages, which greatly reduces the cable length of the welding power supply and reduces the resistance and inductance of the welding circuit, thereby ensuring the stability of the welding process.

[0021] As a further preference, the rigid track includes a track body, a locking member and a tooth groove, the tooth groove is arranged on the outer wall of the track body, and the locking member connects both ends of the track body so that the track body evenly surrounds the sea pipe.

[0022] By adopting the above technical solution, the locking parts connect the two ends of the track body, so that the track body can be stably installed on the submarine pipeline, and the tooth grooves surround the submarine pipeline together with the track body, so that the single-torch welding trolley and the double-torch welding trolley can move stably on the track body, and then perform all-position welding around the submarine pipeline.

[0023] As a further preference, the welding system further includes a gas supply mechanism for providing welding gas to the bottom sealing and hot welding equipment and the filling and covering welding equipment, and a proportioner for proportioning gas.

[0024] By adopting the above technical solution, the gas supply mechanism provides welding gas for welding operations, which can achieve control of the hardness of the weld and heat-affected zone, and improve the corrosion resistance of the submarine pipeline in acidic environment conditions.

[0025] In general, the above technical solutions conceived by this application have the following technical advantages compared with the existing technologies:

[0026] 1. The back cover and hot welding of this application are performed using a CMT welding power source. Due to the low heat input during welding, the gravity of the molten pool metal, and the small arc force, defects such as weld penetration and weld collapse are less likely to occur. It is easy to obtain a smooth weld at the root, and it is easier to achieve excess height control under the conditions of all-position welding of submarine pipelines. Without the use of a copper backing, a single-sided welding and double-sided forming effect can be achieved under gapless assembly, ensuring complete fusion of the weld root, ensuring the integrity and strength of the weld, and providing high heat input. At the same time, the filling efficiency is high during filling and capping welding. The welding of submarine pipelines in this application can simplify the welding steps and improve welding efficiency.

[0027] 2. In this application, the bottom sealing and hot welding and the filling and cover welding are all carried out simultaneously from both sides of the sea pipe to further improve the welding efficiency.

[0028] 3. The welding system of this application is applicable to a full range of submarine pipes, including ordinary carbon steel, acid pipes and composite pipes. By delivering welding gas through a gas supply mechanism and adjusting the gas ratio using a proportioner, the hardness of the weld and heat-affected zone can be controlled, thereby improving the corrosion resistance of the submarine pipe in acidic environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the overall structure of the back cover and heat welding equipment provided in the embodiment of the present application;

[0030] Figure 2 This is a schematic diagram of the overall structure of the first frame provided in an embodiment of the present application;

[0031] Figure 3 This is a schematic diagram of a top view of the structure of the first conveyor frame provided in an embodiment of the present application;

[0032] Figure 4 This is a schematic diagram of the overall structure of the filling and capping welding equipment provided in an embodiment of the present application;

[0033] Figure 5 It is a schematic diagram of the overall structure of the second frame provided in an embodiment of the present application.

[0034] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0035] 1. Back-sealing and hot-welding equipment; 11. CMT welding power supply; 12. Single-torch welding carriage; 13. First conveyor frame; 131. V-shaped placement platform; 132. Conveyor rollers; 14. First frame; 15. Single-torch control box; 2. Filling and cover welding equipment; 21. Pulse welding power supply; 22. Dual-torch welding carriage; 23. Second conveyor frame; 24. Second frame; 25. Dual-torch control box; 3. Rigid track; 31. Track body; 32. Tooth groove; 33. Locking parts. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0037] Reference Figure 1-5 The present application discloses an efficient welding system for single-sided welding and double-sided forming of sea pipes, which can be applied to sea pipes of 6 inches and above. The types of sea pipes can be a full range of sea pipes such as ordinary carbon steel, acid pipes and composite pipes, including bottom sealing and hot welding equipment 1, filling and covering welding equipment 2, rigid rails 3 and connectors. After the bottom sealing and hot welding of the sea pipe are performed by the bottom sealing and hot welding equipment 1, the sea pipe is transferred, and then the filling welding and covering welding of the sea pipe are performed by the filling and covering welding equipment 2. Specifically, the bottom sealing and hot welding equipment 1 and the filling and covering welding equipment 2 are arranged in sequence along the conveying direction of the sea pipe. After the bottom sealing and hot welding of the sea pipe are performed by the bottom sealing and hot welding equipment 1, the sea pipe is conveyed to the filling and covering welding equipment 2 for filling welding and covering welding.

[0038] In this embodiment, the bottom sealing and heat welding equipment 1 includes a first conveyor frame 13. A V-shaped placement platform 131 for placing the sea pipe and arranged horizontally is provided on the top of the first conveyor frame 13. The sea pipe can be stably placed on the V-shaped placement platform 131. A butt joint is used to connect and assemble two sea pipes with U-shaped grooves, and then bottom sealing welding and heat welding are performed.

[0039] Specifically, the bottom sealing and heat welding equipment 1 also includes a first welding unit, which includes a CMT welding power supply 11, a single-torch welding carriage 12, a first frame 14, and a single-torch control box 15. The CMT welding power supply 11, the single-torch welding carriage 12, and the single-torch control box 15 are all placed on the first frame 14. The configuration of the first frame 14 can significantly reduce the length of the welding power supply cable, reduce the resistance and inductance of the welding circuit, and thus ensure the stability of the welding process. The single-torch welding carriage 12 is fixedly connected to a CMT welding gun electrically connected to the CMT welding power supply 11. The single-torch control box 15 is also electrically connected to the CMT welding gun. During welding, a rigid track 3 is installed on the subsea pipeline, and the rigid track 3 surrounds the outer wall of the subsea pipeline. The single-torch welding carriage is then installed on the rigid track 3. The single-torch welding carriage 12 moves around the subsea pipeline, and the CMT welding gun on the single-torch welding carriage 12 can perform bottom sealing welding and heat welding on the subsea pipeline. Using CMT welding power source 11 for backing welding and hot welding, without using copper backing, it can achieve single-sided welding and double-sided forming effect under gapless assembly, ensuring complete fusion of the weld root and ensuring the integrity and strength of the weld.

[0040] More specifically, the rigid track 3 is removably mounted on the subsea pipeline and surrounds the outer wall of the subsea pipeline. The rigid track 3 employs a split-tooth structure, specifically comprising a track body 31, a locking member 33, and a tooth groove 32. The tooth groove 32 is arranged on the outer wall of the track body 31. The locking member 33 connects the two ends of the track body 31 to ensure that the track body 31 is evenly wrapped around the subsea pipeline. Pads are evenly spaced between the track body 31 and the subsea pipeline, leaving a gap between the track body 31 and the subsea pipeline. The two ends of the tooth groove 32 are connected to form a ring-shaped integral structure. The single-torch welding carriage 12 is removably mounted on the rigid track 3 and interacts with the tooth groove 32 to achieve full-position movement around the subsea pipeline. Specifically, a motor is fixedly mounted on the single-torch welding carriage 12. The motor's output shaft has a gear that meshes with the tooth groove 32. Rotation of the motor enables the overall movement of the single-torch welding carriage 12. This device is a common structure in the art and will not be described in detail. The CMT welding torch on the single-torch welding carriage 12 is directed toward the subsea pipeline for welding.

[0041] Furthermore, to improve welding efficiency, two first welding units are provided, one on each side of the sea pipe. During welding, the rigid rail 3 is first installed on the sea pipe, and then the single-torch welding trolleys 12 on both sides of the sea pipe are removed and installed on the rigid rail 3. Welding can then begin.

[0042] As a further preference, both sides of the V-shaped placement platform 131 are rotatably connected with conveying rollers 132, the rotation axis of the conveying rollers 132 is perpendicular to the sea pipe, and a directional conveying channel is formed between the two conveying rollers 132. There are multiple groups of conveying rollers 132 along the opening direction of the V-shaped placement platform 131. After the sea pipe is sealed and hot-welded on the first conveying rack 13, the conveying rollers 132 enable the sea pipe to be moved in the V-shaped placement platform 131 to facilitate the transfer of the sea pipe for subsequent welding operations.

[0043] Furthermore, the filling and cover welding equipment 2 includes a second welding unit, which includes a pulse welding power supply 21 and a double-torch welding trolley 22 for welding sea pipes, and also includes a second conveyor frame 23, a second frame 24 and a double-torch control box 25. The pulse welding power supply 21, the double-torch welding trolley 22 and the double-torch control box 25 are all placed on the second frame 24. The setting of the second frame 24 can greatly reduce the cable length of the welding power supply, reduce the resistance and inductance of the welding circuit, and thus ensure the stability of the welding process. The structure of the second conveyor frame 23 is the same as that of the first conveyor frame 13. After the sea pipe is transferred from the first conveyor frame 13 to the second conveyor frame 23, filling and cover welding are performed. The actual operation The first conveyor rack 13 and the second conveyor rack 23 can be connected into a whole to form a complete pipeline transmission channel, which passes through the bottom sealing and hot welding equipment 1 and the filling and covering welding equipment 2 to facilitate the transportation of submarine pipes. Two welding guns electrically connected to the pulse welding power supply 21 are fixedly connected to the double-torch welding carriage 22. The two welding guns of each double-torch welding carriage 22 are respectively connected to a pulse welding power supply 21. The gun distance between the two welding guns is 50mm to 100mm. When the gun distance is less than 50mm, the two arcs of the double torches interfere with each other seriously, and stable weld bead formation cannot be achieved; when the gun distance is greater than 100mm, although there is no interference between the arcs, it is not suitable for efficient welding of submarine pipes of 10 inches and below. A dual-torch welding trolley 22 and a pulse welding power supply 21 are used to perform filling welding and cover welding on the sea pipe, which has the characteristics of high welding efficiency and also has the function of single-torch welding; the dual-torch control box 25 is electrically connected to the dual-torch welding trolley 22 to control the dual-torch welding trolley 22, and the dual-torch welding trolley 22 can be detachably mounted on the rigid track 3 to move around the sea pipe. The connection method between the dual-torch welding trolley 22 and the rigid track 3 is the same as the connection method between the single-torch welding trolley 12 and the rigid track 3, and the two welding guns of the dual-torch welding trolley 22 are facing the sea pipe for welding.

[0044] Similarly, to improve welding efficiency, two second welding units are provided, one on each side of the sea pipe. During welding, the rigid rail 3 is first installed on the sea pipe, and then the dual-torch welding carriages 22 on both sides of the sea pipe are removed and installed on the rigid rail 3 to begin welding.

[0045] In addition, the welding system of the present application also includes a gas supply mechanism and a proportioner (not shown in the figure), which provides welding gas to the bottom sealing and hot welding equipment 1 and the filling and covering welding equipment 2 through the gas supply mechanism, wherein the proportioner adopts the existing gas mixing proportioner in the welding field. The gas can be proportioned by the proportioner, and the hardness of the weld and the heat-affected zone can be controlled by flexibly adjusting the ratio of Ar gas and CO2 gas, thereby improving the H2S stress corrosion resistance of the submarine pipeline under acidic environment conditions.

[0046] The specific steps for welding sea pipes by the welding system of this application are as follows:

[0047] S1, place the U-shaped grooved sea pipe on the first conveyor rack 13 for assembly, and the parts to be welded are Figure 3 The connecting seam at A in the middle;

[0048] S2. Install a rigid track 3 on the sea pipe and install two single-torch welding carriages 12 on the rigid track 3;

[0049] S3. Regulate the required gas ratio and flow rate through the proportioner, and use the CMT welding gun on the single-torch welding carriage 12 to perform bottom sealing welding and hot welding on both sides of the submarine pipeline;

[0050] S4, remove the single-torch welding trolley 12 from the rigid track 3, transfer the sea pipe to the second conveyor rack 23, and then install the dual-torch welding trolley 22;

[0051] S5. Use the welding gun on the double-torch welding carriage 22 to perform filling welding and cover welding on both sides of the sea pipe.

[0052] The weld root of the sea pipe welded by the welding system of the present application is flat, the weld is beautifully formed, and there is no lack of fusion defect.

[0053] It should be understood that expressions such as "include" and "may include" used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as "include" and / or "have" may be interpreted as indicating a specific characteristic, number, operation, constituent element, component, or combination thereof, but may not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0054] It should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0056] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they can refer to fixed connection, detachable connection, or integral connection; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0057] It is easy for those skilled in the art to understand that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. An efficient welding system for single-sided welding and double-sided forming of submarine pipes, characterized in that: It comprises a bottom sealing and heat welding device (1), a filling and cover welding device (2) and a rigid track (3), wherein the bottom sealing and heat welding device (1) and the filling and cover welding device (2) are arranged in sequence along the conveying direction of the pipeline; The bottom sealing and heat welding equipment (1) comprises a first welding unit, the first welding unit comprises a CMT welding power source (11) and a single-torch welding carriage (12), and the single-torch welding carriage (12) is fixedly connected to a CMT welding gun electrically connected to the CMT welding power source (11); The rigid track (3) can be detachably mounted on the sea pipe and surround the outer wall of the sea pipe. When welding the sea pipe, the single-torch welding trolley (12) can be detachably mounted on the rigid track (3) to move around the sea pipe. The filling and capping welding equipment (2) is used for welding the sea pipe after the bottom sealing and heat welding by the CMT welding gun are completed.

2. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 1, characterized in that: Two first welding units are provided, and the two first welding units are respectively provided on both sides of the sea pipe; the first welding unit also includes a first frame (14) for placing a CMT welding power source (11) and a corresponding single-torch welding trolley (12).

3. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 1, characterized in that: The bottom sealing and heat welding equipment (1) further comprises a first conveying frame (13), on which a V-shaped placement platform (131) for placing a sea pipe and arranged horizontally is provided.

4. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 3, characterized in that: Both sides of the V-shaped placement platform (131) are rotatably connected to conveying rollers (132), the rotation axes of the conveying rollers (132) are perpendicular to the sea pipe, and a directional conveying channel is formed between the two conveying rollers (132). Multiple groups of conveying rollers (132) are arranged along the opening direction of the V-shaped placement platform (131).

5. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 1, characterized in that: The filling and covering welding equipment (2) includes a second welding unit, which includes a pulse welding power supply (21) and a double-torch welding trolley (22). Two welding guns electrically connected to the pulse welding power supply (21) are fixedly connected to the double-torch welding trolley (22). When welding the sea pipe, the double-torch welding trolley (22) can be detachably mounted on the rigid track (3) to move around the sea pipe, and the two welding guns of the double-torch welding trolley (22) are both facing the sea pipe.

6. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 5, characterized in that: The distance between the two welding guns of the double-torch welding carriage (22) is 50 mm to 100 mm.

7. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 5, characterized in that: The two welding guns of the dual-torch welding carriage (22) are each connected to a pulse welding power source (21).

8. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 7, characterized in that: The second welding units are provided with two, and the two second welding units are respectively provided on both sides of the sea pipe; the second welding units also include a second frame (24) for placing a pulse welding power source (21) and a double-torch welding trolley (22).

9. The high-efficiency welding system for single-sided welding and double-sided forming of submarine pipes according to claim 1, characterized in that: The rigid track (3) comprises a track body (31), a locking member (33) and a tooth groove (32), wherein the tooth groove (32) is arranged on the outer wall of the track body (31), and the locking member (33) connects the two ends of the track body (31) so that the track body (31) is evenly surrounded on the sea pipe.

10. An efficient welding system for single-sided welding and double-sided forming of submarine pipes according to any one of claims 1 to 9, characterized in that: The welding system further comprises a gas supply mechanism for providing welding gas to the bottom sealing and heat welding equipment (1) and the filling and covering welding equipment (2) and a proportioner for proportioning the gas.

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