Welding method for torsion box of container ship and container ship using the same
Patent Information
- Application Number
- CN202611302601.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-26
- Publication Date
- 2026-10-16
AI Technical Summary
[0005]本发明要解决的技术问题是为了克服现有技术中集装箱船抗扭箱的焊接周期长、费工且质量不稳定的缺陷，提供一种集装箱船抗扭箱焊接方法及采用其的集装箱船
[0032]A container ship having a torsion box, wherein the torsion box is welded using the container ship torsion box welding method described above.
Smart Images
Figure CN122913623A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of marine engineering technology, and in particular to a method for welding anti-torsion boxes for container ships and a container ship using the same method. Background Technology
[0002] like Figure 1 As shown, the anti-torsion box 1' of the container ship is a key load-bearing structure in the hull and one of the locations with the highest stress concentration. The welding parts 11' here are mostly single-sided bevel deep penetration welded joints formed by connecting thick high-strength steel plates. On 7000 container ships, the plate thickness can generally reach 45~55mm, and the joint usually adopts a structure with a single-sided 45° bevel on both sides.
[0003] Existing processes typically employ flux-cored carbon dioxide gas shielded welding for the entire welding process. For this type of thick plate deep-penetration groove structure, problems such as a large number of weld beads, large welding deformation, welding stress concentration, high labor intensity for welders, and long welding cycle will occur. At the same time, under windy conditions or with large fluctuations in the on-site environment, the welding process is also prone to defects such as porosity, slag inclusion, and lack of fusion, resulting in unstable welding quality.
[0004] It should be noted that: for ease of labeling, in Figure 1 The first front weld bead is designated WF1' (The Weld Bead on the Front Side 1), the first reverse weld bead is designated WR1' (The Weld Bead on the Reverse Side 1), and the remaining weld beads are designated accordingly. At the weldable location 11', the plate thickness is D'=45mm, the weld depth is d'=15mm, and the weld bead extends beyond the upper / lower edge of the steel plate by h'=7mm. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to overcome the defects of long welding cycle, labor-intensive and unstable quality of anti-torsion box of container ship in the prior art, and to provide a welding method for anti-torsion box of container ship and a container ship using the same method.
[0006] The present invention solves the above-mentioned technical problems through the following technical solution:
[0007] A method for welding a torsion-resistant box for a container ship, the method comprising the following steps:
[0008] S1. Perform reverse welding on the part to be welded, using flux-cored carbon dioxide gas shielded welding. Start from the beginning of the reverse welding and perform multi-layer, multi-pass welding until the first reverse preset weld pass is completed.
[0009] S2. Perform front welding on the part to be welded, using submerged arc automatic welding, starting from the front welding start end, and perform multi-layer, multi-pass deep penetration welding until the front preset weld bead is completed.
[0010] S3. Continue to perform reverse welding on the part to be welded, using flux-cored carbon dioxide gas shielded welding. Starting from the first reverse preset weld bead, perform multi-layer and multi-pass welding until the second reverse preset weld bead is completed.
[0011] In this technical solution, a welding method for the anti-torsion box of a container ship is provided, which adopts an alternating approach of welding on both sides, using flux-cored carbon dioxide gas shielded welding and submerged arc welding. The basic fusion is first formed on the reverse side, and then the deep penetration welding on the front side undertakes the main fusion efficiency, reducing the risk of incomplete fusion and slag inclusions caused by the welding torch not being able to reach the root. Switching welding surfaces midway helps to balance welding shrinkage, which can help to resist the structural constraints of the anti-torsion box part and reduce welding deformation and residual stress concentration. The submerged arc welding on the front side ensures a stable welding process and high consistency of forming, which can improve welding efficiency, shorten the welding cycle, and reduce the dependence on the welder's skill level.
[0012] Preferably, the number of the front-side preset weld beads is less than the sum of the number of the first reverse-side preset weld beads and the second reverse-side preset weld beads.
[0013] In this technical solution, the above settings make the welding amount on both sides more reasonable, further improve welding efficiency, shorten the welding cycle, and control the heat input distribution ratio to avoid excessive deformation after multiple layers and deep penetration welding on the front side.
[0014] Preferably, the number of the first reverse side preset weld beads is the same as the number of the front side preset weld beads.
[0015] In this technical solution, the above settings further avoid deformation displacement caused by excessive unilateral shrinkage, which is beneficial for controlling weld formation and structural springback.
[0016] Preferably, the number of the first reverse side preset weld beads is less than or equal to the number of the second reverse side preset weld beads.
[0017] In this technical solution, the above-mentioned settings facilitate the final completion and shaping of the weld by using subsequent reverse welds after the front welding is completed, thus avoiding the final weld from being biased to one side or insufficient pull-back.
[0018] Preferably, the number of the front preset weld bead, the first back preset weld bead, and the second back preset weld bead is 4 to 10.
[0019] In this technical solution, the above settings avoid the problem of too many weld beads on one side leading to decreased efficiency, excessive heat circulation, and stress accumulation; they also avoid the problem of too few weld beads leading to insufficient penetration and unstable forming, thus helping to balance efficiency, quality, and deformation control.
[0020] Preferably, the strength of the first reverse weld in step S1 is greater than the strength of all other reverse welds in the container ship anti-torsion box welding method.
[0021] In this technical solution, the above-mentioned settings enable the first reverse weld bead to have better load-bearing capacity, reducing the possibility of collapse, burn-through, root cracking, or root metal loss when subsequent weld beads are stacked.
[0022] Preferably, the steps of the container ship anti-torsion box welding method further include:
[0023] S01. Grind the area to be welded to remove rust, scale, and oil stains within a 15-25mm range on both sides of the weld.
[0024] Step S01 is completed before step S1.
[0025] In this technical solution, by pre-cleaning the parts to be welded through the above settings, the probability of defects such as porosity, slag inclusions, and lack of fusion can be reduced, which is conducive to forming a stable bevel surface condition and improving the purity of the weld.
[0026] Preferably, the steps of the container ship anti-torsion box welding method further include:
[0027] S02. Heat the area within 90-110mm on both sides of the part to be welded to 90-110℃ using electric heating or flame heating.
[0028] Step S02 is completed before step S1 and after step S01.
[0029] In this technical solution, the above-mentioned settings preheat the area to be welded, reducing the risk of cold crack formation, improving the toughness of thick plate welded joints, and also helping to reduce residual welding stress and improve post-weld quality stability.
[0030] Preferably, the diameter of the core in the flux-cored carbon dioxide gas shielded welding is 1.2~1.4mm, and the diameter of the core in the submerged arc welding is 4.0~6.0mm.
[0031] In this technical solution, the above settings allow the two welding processes to be matched in terms of deposition efficiency, penetration capability, and wire feeding stability. A smaller core diameter is beneficial for stable arc initiation and fine filling in flux-cored CO2 gas shielded welding; a larger core diameter is beneficial for high-efficiency, large-scale deposition in submerged arc welding.
[0032] A container ship having a torsion box, wherein the torsion box is welded using the container ship torsion box welding method described above.
[0033] In this technical solution, by providing this container ship, the construction quality and efficiency of the anti-torsion container are improved, the ability of the hull to resist torsional loads is enhanced, the torsional deformation and stress of the open hull are reduced, and the container ship has good structural durability.
[0034] The positive and progressive effects of this invention are as follows:
[0035] By providing a welding method for the anti-torsion box of the container ship, a scheme is adopted that alternates between positive and negative welding, flux-cored carbon dioxide gas shielded welding and submerged arc welding. The basic deposition is first formed on the negative side, and then the deep penetration welding on the front side undertakes the main deposition efficiency, reducing the risk of incomplete fusion and slag inclusions caused by the welding torch not being able to reach the root. Switching welding surfaces midway helps to balance welding shrinkage, which can resist the structural constraints of the anti-torsion box part and reduce welding deformation and residual stress concentration. The submerged arc welding on the front side has a stable welding process and high uniformity of formation, which can improve welding efficiency, shorten the welding cycle, and reduce the dependence on the welder's skill level.
[0036] By providing this container ship, the construction quality and efficiency of the torsion-resistant container can be improved, the hull's ability to resist torsional loads can be enhanced, the torsional deformation and stress of the open hull can be reduced, and the container ship can have good structural durability. Attached Figure Description
[0037] Figure 1 This is a schematic diagram of the welding method for anti-torsion boxes of container ships in the background art.
[0038] Figure 2 This is a schematic diagram of a container ship anti-torsion box welding method according to an embodiment of the present invention.
[0039] Figure 3 This is a flowchart of a container ship anti-torsion box welding method according to an embodiment of the present invention.
[0040] Explanation of reference numerals in the attached figures:
[0041] exist Figure 1 middle:
[0042] Torsion box 1'
[0043] Part 11' to be welded
[0044] exist Figure 2 middle:
[0045] Torsion box 1
[0046] Part 11 to be welded
[0047] First reverse side pre-set weld bead 121
[0048] Pre-set weld bead 122 on the front
[0049] Second reverse side pre-set weld bead 123 Detailed Implementation
[0050] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments.
[0051] like Figure 2 , Figure 3 As shown in the figure, this embodiment provides a method for welding anti-torsion boxes for container ships, the steps of which include:
[0052] S1. Perform reverse welding on the part to be welded 11 using flux-cored carbon dioxide gas shielded welding. Starting from the beginning of the reverse welding, perform multi-layer and multi-pass welding until the first reverse preset weld 121 is completed.
[0053] S2. Perform front welding on the part to be welded 11 using submerged arc automatic welding. Starting from the front welding start point, perform multi-layer, multi-pass deep penetration welding until the front preset weld 122 is completed.
[0054] S3. Continue to perform reverse welding on the part to be welded 11, using flux-cored carbon dioxide gas shielded welding. Starting from the first reverse preset weld bead 121, perform multi-layer and multi-pass welding until the second reverse preset weld bead 123 is completed.
[0055] In this technical solution, a welding method for the anti-torsion box of the container ship is provided, which adopts an alternating method of welding on both sides, flux-cored carbon dioxide gas shielded welding and submerged arc welding. The basic deposition is first formed on the reverse side, and then the deep penetration welding on the front side undertakes the main deposition efficiency, reducing the risk of incomplete fusion and slag inclusion caused by the welding torch not being able to reach the root. Switching the welding surface midway helps to balance welding shrinkage, which can resist the structural constraints of the anti-torsion box 1 part and reduce welding deformation and residual stress concentration. The submerged arc welding on the front side is stable and has high uniformity of formation, which can improve welding efficiency, shorten the welding cycle, and reduce the dependence on the welder's skill level.
[0056] It should be noted that: for ease of labeling, in Figure 2 The first front weld bead is designated WF1 (The Weld Bead on the Front Side 1), the first reverse weld bead is designated WR1 (The Weld Bead on the ReverseSide 1), and the remaining weld beads are labeled accordingly.
[0057] "Multi-layer multi-pass welding" here refers to a general welding process that fills the weld in layers and passes along the thickness and width directions, gradually completing the groove filling through multiple weld passes to meet the requirements of weld formation and joint strength. "Multi-layer multi-pass deep penetration welding" is based on multi-layer multi-pass welding, using welding specifications with greater penetration for the root pass and / or each subsequent pass, allowing the weld metal to more fully melt the groove sidewalls and achieve good fusion with the root during the multi-pass filling process. Its core purpose is to prioritize the fusion of the groove sidewalls and the root, reducing the probability of welding defects such as incomplete fusion. Both are clearly existing technologies in this field, and those skilled in the art should be able to recognize and implement them. Here, "front" refers to the upward side in the vertical direction, and "back" refers to the downward side in the vertical direction; the back side requires overhead welding. Compared with using a single flux-cored CO2 gas shielded welding for both front and back sides, the above steps can reduce the number of weld passes, rework, and subsequent grinding and straightening work.
[0058] Furthermore, using submerged arc welding (SAW) on both sides is generally not feasible. While SAW offers advantages such as high deposition efficiency and stable weld formation, its welding process typically requires space for flux placement, flux recovery, and welding head movement, placing high demands on the available space around the welding area. In the area below and around the welding portion 11 of the torsion box 1 (i.e., the "reverse side"), other components or plates are often present, making the welding torch, welding head, and flux device susceptible to interference. This hinders access to the weld root, resulting in insufficient operating space and making stable SAW welding difficult. In contrast, flux-cored CO2 gas shielded welding torches are smaller and more mobile, making them more suitable for reverse welding in space-constrained areas with significant component interference. Therefore, this embodiment combines reverse flux-cored CO2 gas shielded welding with front SAW, better balancing feasibility, welding efficiency, and welding quality.
[0059] Flux-cored carbon dioxide gas shielded welding and submerged arc welding are both existing welding technologies, which should be understandable and implementable by those skilled in the art.
[0060] In this embodiment, the number of pre-set weld beads 122 on the front side is less than the sum of the number of the first pre-set weld beads 121 on the back side and the second pre-set weld beads 123 on the back side, making the welding amount on both sides more reasonable, further improving welding efficiency, shortening the welding cycle, and controlling the heat input distribution ratio to avoid excessive deformation after multiple layers and multiple deep penetration welding on the front side.
[0061] In this embodiment, the number of the first reverse side preset weld beads 121 is the same as the number of the front side preset weld beads 122, which further avoids deformation and displacement caused by excessive shrinkage on one side, and is beneficial to control weld formation and structural springback.
[0062] In this embodiment, the number of the first reverse side preset weld beads 121 is less than or equal to the number of the second reverse side preset weld beads 123. This is beneficial to complete the final filling and shaping by using the subsequent reverse side weld beads after the front side welding is completed, and to avoid the final weld being biased to one side or insufficient pull-back.
[0063] In this embodiment, the number of the front preset weld bead 122, the first reverse preset weld bead 121, and the second reverse preset weld bead 123 is 4 to 10. This avoids the efficiency decrease, excessive heat cycling, and stress accumulation caused by too many weld beads on one side at one time; it also avoids insufficient penetration and unstable forming caused by too few weld beads, which helps to balance efficiency, quality, and deformation control.
[0064] In this embodiment, the number of the front preset weld 122 and the first reverse preset weld 121 are both 6, and the number of the second reverse preset weld 123 is 9. The reverse welding in S3 starts from the surface of the sixth reverse weld WR6 that has been completed in S1. In other embodiments, the above number should be determined according to the parameters required by the anti-torsion box 1, and can be other values in the range of 4 to 10.
[0065] In this embodiment, the strength of the first reverse weld pass WR1 in step S1 is greater than the strength of all other reverse weld passes (WR2~WR15) in the container ship anti-torsion box welding method. This gives the first reverse weld pass better load-bearing capacity and reduces the possibility of collapse, burn-through, root cracking, or root metal loss when subsequent weld passes are stacked. This "strength" adjustment is achieved in this embodiment using a larger maximum welding current. In other embodiments, it can be achieved through other adjustments to the welding parameters (see below), with the adjustment scheme referring to existing technologies.
[0066] In this embodiment, the steps of the container ship anti-torsion box welding method further include:
[0067] S01. Grind the area to be welded 11 to remove rust, scale, and oil stains within a 20mm radius on both sides of the weld.
[0068] Step S01 is completed before step S1.
[0069] Thus, pre-cleaning the area to be welded 11 reduces the probability of defects such as porosity, slag inclusions, and lack of fusion, which is beneficial for forming a stable bevel surface and improving weld purity. In other embodiments, oil stains within a 15-25mm range on both sides of the weld can also be cleaned to achieve a similar effect.
[0070] In this embodiment, the steps of the container ship anti-torsion box welding method further include:
[0071] S02. Heat the area within 100mm on both sides of the part to be welded 11 to 100℃ using electric heating or flame heating.
[0072] Step S02 is completed before step S1 and after step S01.
[0073] Preheating the area 11 to be welded reduces the risk of cold cracking, improves the toughness of the welded joint in thick plates, and helps reduce residual welding stress, thereby enhancing post-weld quality stability. In other embodiments, a similar effect can be achieved by heating a 90-110 mm area on both sides of the area 11 to be welded to 90-110°C.
[0074] In this embodiment, the steps of the container ship anti-torsion box welding method further include: selecting welding materials that match the steel plate material; and ensuring a smooth transition with the base material during submerged arc automatic welding of the cover surface to further improve the welding effect and enhance the post-weld quality.
[0075] In this embodiment, the core diameter for flux-cored CO2 gas shielded welding is 1.2 mm, and the core diameter for submerged arc welding is 5.0 mm, allowing the two welding processes to be matched in terms of deposition efficiency, penetration capability, and wire feeding stability, respectively. A smaller core diameter is beneficial for stable arc initiation and fine filling in flux-cored CO2 gas shielded welding; a larger core diameter is beneficial for high-efficiency, large-scale deposition in submerged arc welding. In other embodiments, the core diameter for flux-cored CO2 gas shielded welding can also be other values within the range of 1.2 to 1.4 mm, and the core diameter for submerged arc welding can be other values within the range of 4.0 to 6.0 mm, to achieve similar effects.
[0076] In this embodiment, the specific process parameters are as follows:
[0077]
[0078] Taking a 10m long weld seam of the anti-torsion box 1 as an example, using only flux-cored carbon dioxide gas shielded welding, the welding process would take approximately 11 hours. Using the anti-torsion box welding method of this embodiment, with submerged arc welding on the front side, the process would take approximately 3 hours, increasing welding production efficiency by 3-4 times. At the welding location 11, the plate thickness is D=45mm, the weld depth is d=15mm, and the weld bead extends h=7mm beyond the upper / lower ends of the steel plate.
[0079] This embodiment also provides a container ship having a torsion box 1, which is welded to the torsion box 1 using the container ship torsion box welding method described above, thereby improving the construction quality and efficiency of the torsion box 1, enhancing the hull's ability to resist torsional loads, reducing torsional deformation and stress in the open hull, and giving the container ship good structural durability.
[0080] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.
Claims
1. A method for welding anti-torsion boxes for container ships, characterized in that, The steps of the container ship anti-torsion box welding method include: S1. Perform reverse welding on the part to be welded, using flux-cored carbon dioxide gas shielded welding. Start from the beginning of the reverse welding and perform multi-layer, multi-pass welding until the first reverse preset weld pass is completed. S2. Perform front welding on the part to be welded, using submerged arc automatic welding, starting from the front welding start end, and perform multi-layer, multi-pass deep penetration welding until the front preset weld bead is completed. S3. Continue to perform reverse welding on the part to be welded, using flux-cored carbon dioxide gas shielded welding. Starting from the first reverse preset weld bead, perform multi-layer and multi-pass welding until the second reverse preset weld bead is completed.
2. The container ship anti-torsion box welding method as described in claim 1, characterized in that, The number of the pre-set weld beads on the front side is less than the sum of the number of the first pre-set weld beads on the back side and the second pre-set weld beads on the back side.
3. The container ship anti-torsion box welding method as described in claim 2, characterized in that, The number of the first reverse side preset weld beads is the same as the number of the front side preset weld beads.
4. The container ship anti-torsion box welding method as described in claim 1, characterized in that, The number of the first reverse side preset weld beads is less than or equal to the number of the second reverse side preset weld beads.
5. The container ship anti-torsion box welding method as described in claim 1, characterized in that, The number of the front preset weld bead, the first back preset weld bead, and the second back preset weld bead is 4 to 10.
6. The method for welding anti-torsion boxes for container ships as described in claim 1, characterized in that, The strength of the first reverse weld in step S1 is greater than the strength of all other reverse welds in the container ship anti-torsion box welding method.
7. The method for welding anti-torsion boxes for container ships as described in claim 1, characterized in that, The steps of the container ship anti-torsion box welding method further include: S01. Grind the area to be welded to remove rust, scale, and oil stains within a 15-25mm range on both sides of the weld. Step S01 is completed before step S1.
8. The method for welding anti-torsion boxes for container ships as described in claim 7, characterized in that, The steps of the container ship anti-torsion box welding method further include: S02. Heat the area within 90-110mm on both sides of the part to be welded to 90-110℃ using electric heating or flame heating. Step S02 is completed before step S1 and after step S01.
9. The method for welding anti-torsion boxes for container ships as described in claim 1, characterized in that, The diameter of the core in the flux-cored carbon dioxide gas shielded welding is 1.2~1.4mm, and the diameter of the core in the submerged arc automatic welding is 4.0~6.0mm.
10. A container ship having a torsion-resistant box, characterized in that, The anti-torsion box is welded using the container ship anti-torsion box welding method as described in any one of claims 1-9.