Method for straightening a sheet of a ship

Abstract

This invention discloses a method for straightening thin plates in shipbuilding. The method includes the following steps: straightening the thin plates of the superstructure in a bottom-up order; dividing the plate into several areas to be straightened on the back side of the side with structural components, using every two adjacent structural components; sequentially performing heat straightening on each area, ensuring that adjacent areas are spaced at least one area apart. This method improves the precise control of thermal deformation. Heating the spaced areas sequentially effectively prevents the heat-affected zones (HAZs) from overlapping, ensuring sufficient cooling space between each heated area, allowing heat space and time to conduct and dissipate, thus preventing temperature accumulation in the HAZ. This method also generates more uniform shrinkage force, achieving smoother and more controllable straightening of plate deformation.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding, and more particularly to a method for straightening thin plates in ships. Background Technology

[0002] As a vital functional area for crew living and working, the ship's superstructure is primarily constructed from thin steel plates, typically 6-7 mm thick. During construction, this thin-plate structure undergoes numerous processes including cutting, welding, hoisting, and transportation, making it highly susceptible to significant welding deformation and overall instability, resulting in uneven surfaces on decks, bulkheads, and other surfaces. Because the superstructure demands extremely high aesthetic standards for both the living environment and structural precision, regulations typically require flatness deviations to be controlled within ±6 mm. Therefore, effective correction of deformed areas (fire straightening) is an indispensable and crucial step in the construction process.

[0003] However, existing straightening processes for thin-plate deformation in superstructures generally suffer from a lack of systematicity and standardization. They typically employ an empirical approach of "straightening only where unevenness is observed," meaning that only visible or locally detected protrusions are straightened using flame heating. This localized, isolated straightening method lacks sufficient consideration of the overall structural deformation trend and residual stress distribution. As a result, the stress in the straightened area fails to be effectively released or balanced during cooling, often transferring to adjacent areas. This leads to new deformations in other areas after the straightened area is leveled, creating a vicious cycle that severely restricts overall straightening efficiency and the achievement of final accuracy goals.

[0004] Excessive unevenness in the thin-plate superstructure poses significant risks. First, it severely compromises the aesthetics and comfort of living quarters, failing to meet shipowner and regulatory requirements for high-quality living areas. Second, deformation affects the quality of subsequent interior material installation, leading to installation difficulties, uneven seams, or voids. More importantly, excessive wave deformation weakens the local stiffness and stability of the thin-plate structure, potentially becoming a source of fatigue and impacting the structural safety and service life of the superstructure. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of the existing technology in which the straightening process lacks systematic operation specifications and the flatness of the straightened thin plate is low and difficult to meet the use requirements, and to provide a method for straightening thin plates of ships.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution:

[0007] This invention provides a method for straightening thin plates in ships. The thin plates include a plate body and a plurality of structural members welded at intervals on the inner surface of the plate body. The plurality of thin plates are connected to form a superstructure. The method for straightening thin plates in ships includes the following steps: straightening the thin plates in a bottom-up order on the superstructure; dividing the plate body into a plurality of areas to be straightened on the back side of the plate body on the side where the structural members are provided, with each pair of adjacent structural members forming a plurality of areas to be straightened; performing fire straightening on each area to be straightened in sequence, and ensuring that adjacent areas to be straightened are at least one area apart in position.

[0008] In this scheme, the shipbuilding thin plate straightening method improves the precise control of thermal deformation. Since pyrotechnic straightening utilizes the contraction force generated by localized heating followed by cooling to correct deformation, sequential heating of alternating areas to be straightened effectively prevents the heat-affected zones (HAZs) of two areas from overlapping. This ensures sufficient cooling space between each heated area, allowing heat room and time to conduct and dissipate, preventing the accumulation of temperature in the HAZ. Excessive temperature accumulation in the HAZ can cause changes in the metallographic structure, thereby impairing the material's mechanical properties and corrosion resistance. Therefore, compared to conventional pyrotechnic straightening operations, this shipbuilding thin plate straightening method generates a more uniform contraction force, achieving smoother and more controllable straightening of plate deformation.

[0009] Preferably, the ship thin plate straightening method further includes: in the heating position, the heating starting point is set close to the edge of the area to be straightened; in the heating direction, long linear heating is performed along the extension direction of the structural member; in the heating sequence, the concave area is heated first and then the convex area is heated.

[0010] In this scheme, the heating starting point is set near the edge of the area to be corrected, avoiding the central empty area. This is because if heating is applied within the empty area, the required heating temperature is high, and if the temperature is not well controlled, it will result in unevenness at the heated point, even though the overall surface is basically leveled. Since the welds between the structural components and the plate are generally long straight welds, and the deformation of thin plates is generally caused by angular deformation due to these long straight welds, heating along the extension direction of the structural components in a long linear pattern can form a continuous, constrained plastic deformation band. When the deformation band cools, the synchronous contraction of the entire deformation band can effectively level the bending caused by angular deformation. Since there is usually residual compressive stress in the recessed area and residual tensile stress in the protruding area, if the protruding area is heated first, its cooling contraction will further increase the tensile stress and exacerbate the deformation of the recessed area. Heating the recessed area first releases the compressive stress through the expansion and contraction process, providing a stable foundation for the subsequent correction of the protruding area, thereby avoiding stress superposition and worsening of deformation.

[0011] Preferably, during repeated heating, the heating starting point is adjusted within a range of 10 to 20 mm from the structural member in the area to be corrected.

[0012] In this solution, adjusting the heating starting point within a range of 10 to 20 mm from the structural component can avoid direct heating on the back of the structural component. Since the structural component generally has load-bearing requirements, direct hot work on the back of the structural component will damage the original metal fiber state formed by welding and reduce the load-bearing capacity of the structural component.

[0013] Preferably, the ship thin plate straightening method further includes the following steps: dividing the thin plates into outer deck, inner deck, outer wall and inner wall according to the connection position, and performing fire straightening on each of them using different parameters.

[0014] In this scheme, the functions and performance requirements of the thin plates in different positions are not the same. Therefore, using different parameters to perform fire straightening on the thin plates in different positions can better adapt to the needs of the thin plates.

[0015] Preferably, in the step of dividing the several thin plates into outer deck, inner deck, outer perimeter wall and inner perimeter wall according to the connection position, and performing fire correction using different parameters, the fire correction of the outer deck includes: maintaining a distance of 45mm to 55mm between the heating path and the spray cooling water during heating correction, heating temperature less than 900°C, heating width not greater than 30mm, and heating depth of 2 / 3 of the plate thickness.

[0016] In this scheme, the above parameters can meet the performance requirements of the outer deck.

[0017] Preferably, in the step of dividing the several thin plates into outer deck, inner deck, outer perimeter wall and inner perimeter wall according to the connection position, and performing pyrotechnic correction using different parameters, the pyrotechnic correction of the inner deck includes: maintaining the distance between the heating line and the nozzle cooling water at no more than 100 mm during heating correction, the heating temperature at 890°C to 910°C, and the heating width at no more than 40 mm.

[0018] In this scheme, the above parameters can meet the performance requirements of the inner deck.

[0019] Preferably, when a region to be corrected has both concave and convex deformations, the pyrotechnic correction of the inner deck further includes: first heating the concave and convex areas with short linear heating paths, and then heating the convex areas.

[0020] In this solution, the convex and concave deformation areas are usually closely adjacent. If a long heating line is used, it will cover both the convex and concave areas at the same time, which will aggravate the convex or concave areas. Short lines can be flexibly selected according to the needs of the convex or concave areas.

[0021] Preferably, in the step of dividing the several thin plates into outer deck, inner deck, outer wall and inner wall according to the connection position, and performing pyrotechnic correction using different parameters, the pyrotechnic correction of the inner wall includes: maintaining a distance of 45mm to 55mm between the heating line and the nozzle cooling water during heating correction, a heating temperature of 690°C to 710°C, and a heating width of 25mm to 35mm.

[0022] In this solution, the above parameters can meet the performance requirements of the inner wall.

[0023] Preferably, in the step of dividing the several thin plates into outer deck, inner deck, outer perimeter wall and inner perimeter wall according to the connection position, and performing pyrotechnic correction using different parameters, the pyrotechnic correction of the outer perimeter wall includes: maintaining the distance between the heating line and the nozzle cooling water at 45mm to 55mm during heating correction, and the heating temperature at 940°C to 960°C.

[0024] In this solution, the above parameters can meet the performance requirements of the outer wall.

[0025] Preferably, the step of correcting the thin plates of the superstructure in a bottom-up order specifically includes: first correcting the first layer of thin plates, then correcting them in the order of inner deck, outer deck, inner wall, and outer wall; after the first layer is corrected, the next layer is corrected in the same order.

[0026] In this scheme, correcting the lower region first allows it to cool down, and the cooled lower region can then become a rigid support point. Furthermore, a correction reference surface is formed in the lower region, allowing for accurate prediction of deformation when the upper region is corrected.

[0027] The positive and progressive effects of this invention are as follows:

[0028] The ship plate straightening method of the present invention improves the precise control of thermal deformation. Since flame straightening utilizes the contraction force generated by localized heating followed by cooling to correct deformation, sequential heating of alternating areas to be straightened effectively prevents the heat-affected zones (HAZs) of two areas from overlapping. This ensures sufficient cooling space between each heated area, allowing heat room and time to conduct and dissipate, preventing the accumulation of temperature in the HAZ. Excessive temperature accumulation in the HAZ can cause changes in the metallographic structure, thereby impairing the material's mechanical properties and corrosion resistance. Therefore, compared to conventional flame straightening operations, this ship plate straightening method generates a more uniform contraction force, achieving smoother and more controllable correction of plate deformation. Attached Figure Description

[0029] Figure 1 This is a flowchart of a ship thin plate straightening method according to an embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the correction sequence of the superstructure in an embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram illustrating the correction sequence of the outer deck in an embodiment of the present invention.

[0032] Figure 4 This is a cross-sectional view of the outer deck according to an embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram illustrating the correction sequence of the inner deck in an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram illustrating the correction sequence of the inner wall in an embodiment of the present invention.

[0035] Figure 7 This is a schematic diagram of the inner wall structure according to an embodiment of the present invention.

[0036] Figure 8 This is a schematic diagram of the hammer impact points on the inner wall of an embodiment of the present invention.

[0037] Figure 9 This is a schematic diagram of the structure of the door and window openings in an embodiment of the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] Superstructure 1;

[0040] Plate 2;

[0041] Structural component 3;

[0042] Outer deck 4;

[0043] Area 5 to be corrected;

[0044] Heating route 6;

[0045] inner deck 7;

[0046] inner wall 8;

[0047] 9. Door and window openings; Detailed Implementation

[0048] The present invention will be described more clearly and completely below with reference to a preferred embodiment and the accompanying drawings.

[0049] like Figures 1 to 9As shown, this embodiment provides a method for straightening thin plates in a ship. The superstructure 1 of the ship is composed of thin plates, with a plate thickness of 6-7 mm. The thin plate includes a plate body 2 and a number of structural members 3 welded at intervals on the inner surface of the plate body 2. The structural members 3 are long beams vertically welded to the plate body 2 to form a T-shaped support structure. The number of structural members 3 are arranged in parallel at intervals on the same outer surface of the plate body 2.

[0050] The method for straightening thin plates of ships utilizes existing pyrotechnic straightening techniques. Before pyrotechnic straightening, preparatory work is required: Before straightening the superstructure 1, personnel must be prepared according to the size and deformation of the superstructure 1. A suitable heating torch must be selected, and the gas supply hose must be kept in good working order. Acetylene is preferred as the combustible gas due to its high calorific value and good straightening efficiency. In other embodiments, natural gas, propane, or other combustible gases can also be used, but natural gas and propane have lower calorific values ​​and poorer straightening efficiency.

[0051] The method for straightening thin plates in ships includes the following steps:

[0052] like Figure 2 As shown, in terms of the overall correction sequence, the thin plate of the superstructure 1 is corrected in the height direction from bottom to top.

[0053] Specifically, the first layer of thin plates is straightened first, starting from the first layer and working upwards. Then the second and third layers are straightened, gradually moving upwards to the next layer. The entire straightening process for the superstructure 1 is as follows: starting from the first layer, following the rule of straightening the inner deck 7 first, then the outer deck 4, the inner enclosure 8 first, then the outer enclosure, and the panel surfaces first, then the door and window openings 9, straightening from the first layer upwards to the second layer and finally to the top layer. Then, the flatness of the straightened area is checked and corrected, and local areas are corrected to ensure that the overall quality meets the requirements. Finally, it is submitted for acceptance.

[0054] In this way, correcting the lower areas, such as the first floor, allows these areas to cool down first, and the cooled lower areas can then become rigid support points. Furthermore, a correction reference surface is formed in the lower areas, allowing for accurate prediction of deformation when correcting the upper areas, such as higher floors.

[0055] In terms of overall area division, several thin plates are divided into outer deck 4, inner deck 7, outer perimeter wall, and inner perimeter wall 8 according to their connection positions, and different parameters are used for fire straightening of each. The functions and performance requirements of the thin plates in different positions are not the same. Therefore, using different parameters for fire straightening of the thin plates in different positions can better adapt to the needs of the thin plates.

[0056] During flame straightening, the back side of the plate 2 where the structural member 3 is located, i.e., the other side of the plate where the structural member 3 is located, is divided into several elongated areas 5 to be straightened by each pair of adjacent structural members 3, i.e., the plate surface between each pair of structural members 3 is the area to be straightened 5. Each area to be straightened 5 is flame straightened sequentially, and adjacent areas to be straightened 5 are separated by at least one area to be straightened 5 in position.

[0057] Specifically, such as Figure 3 As shown, on the outer deck 4, areas 5 to be corrected are set from left to right, and the correction sequence is as follows: Figure 3 The corrections are performed sequentially by number. Among them, the areas to be corrected, numbered 1 to 8 from left to right, are numbered 5, and the correction order is 8, 1, 6, 2, 4, 7, 3, and 5 from left to right.

[0058] Thus, this method of straightening thin plates for ships can improve the precise control of thermal deformation. Since pyrotechnic straightening utilizes the contraction force generated by localized heating followed by cooling to correct deformation, sequential heating of alternating areas 5 to be straightened effectively prevents the heat-affected zones (HAZs) of two areas 5 from overlapping. This ensures sufficient cooling space between each heated area 5, allowing heat space and time to conduct and dissipate, preventing the accumulation of temperature in the HAZ. Excessive temperature accumulation in the HAZ can cause changes in the metallographic structure, thereby impairing the material's mechanical properties and corrosion resistance. Therefore, compared to conventional pyrotechnic straightening operations, this method of straightening thin plates for ships can generate more uniform contraction force, achieving smoother and more controllable straightening of plate deformation.

[0059] Furthermore, the ship thin plate straightening method also includes: in the heating position, the heating starting point is set close to the edge of the area to be straightened 5; in the heating direction, long linear heating is performed along the extension direction of the structural member 3; in the heating sequence, the concave area is heated first and then the convex area is heated.

[0060] Thus, the heating starting point is set close to the edge of the area to be corrected 5, avoiding the central empty space of the area to be corrected 5. This is because if heating is applied within the empty space, the required heating temperature is higher, and if the heating temperature is not well controlled, it will cause the overall surface to be basically flattened, but unevenness will appear at the heated point. Since the weld between the structural component 3 and the plate 2 is generally a long straight weld, and the deformation of the thin plate is generally caused by angular deformation due to the long straight weld, heating along the extension direction of the structural component 3 in a long linear shape can form a continuous constrained plastic deformation band. When the deformation band cools, the synchronous contraction of the entire deformation band can effectively flatten the bending caused by angular deformation. Since there is usually residual compressive stress in the recessed area and residual tensile stress in the protruding area, if the protruding area is heated first, its cooling contraction will further increase the tensile stress, while simultaneously aggravating the deformation of the recessed area. Heating the recessed area first releases the compressive stress through the expansion and contraction process, providing a stable foundation for the subsequent correction of the protruding area, thereby avoiding stress superposition and worsening of deformation.

[0061] In this embodiment, as Figure 3 As shown in the figure, heating route 6 is the path indicated by the arrow in the figure, which heats both sides of the structural component 3.

[0062] Specifically, such as Figure 4 As shown, during multiple heating cycles, the heating starting point is adjusted within the range of 310 to 20 mm from the structural component in the area to be corrected 5.

[0063] Thus, adjusting the heating starting point within a range of 20mm from the structural component 3 can prevent the heating from directly acting on the back of the structural component 3. Since the structural component 3 generally has load-bearing requirements, directly heating the back of the structural component 3 with hot air will damage the original metal fiber state formed by welding and reduce the load-bearing capacity of the structural component 3.

[0064] For the outer deck 4 of the superstructure 1, the deck deformation of the superstructure 1 is generally wavy and local uneven deformation of the butt joint. When straightening the outer deck 4 of the superstructure 1, try to heat and cool it with water on the back of the structural member 3, and it is generally not advisable to strike it directly with a hammer.

[0065] Specifically, in the step of dividing several thin plates into outer deck 4, inner deck 7, outer wall and inner wall 8 according to the connection position, and performing fire correction with different parameters, the fire correction of outer deck 4 includes: maintaining the distance between the heating path 6 and the spray cooling water at 45mm to 55mm during heating correction, heating temperature less than 900°C, heating width not greater than 30mm, and heating depth of 2 / 3 of the plate thickness.

[0066] Thus, the above parameters can meet the performance requirements of the outer deck 4.

[0067] In this embodiment, the flatness correction of the outer deck 4 should begin with the parts with smaller deformations and gradually move towards the parts with larger deformations. If the deck deformation is large and requires multiple people to correct it, the correction must be carried out at several points simultaneously. It is not advisable for too many people to concentrate on correcting a portion of the deformed deck, as this method can easily cause the corrected part to collapse. For decks with large deformations, when multiple heating corrections must be performed on the back of structural component 3, to prevent structural component 3 from collapsing, it is necessary to use support tools to push structural component 3 upwards as temporary reinforcement before proceeding with heating correction.

[0068] For the inner deck 7 of the superstructure 1, since most or all of the inner deck 7 is to be internally fitted and is not an exposed deck, the correction requirements for the inner deck 7 can be appropriately lower than those for the outer deck 4. However, the correction must ensure that the overall flatness of the deck meets the requirements, and after correction, there should be no looseness when stepping on the deck, so that the deck is in a tightened state.

[0069] Specifically, in the step of dividing several thin plates into outer deck 4, inner deck 7, outer wall and inner wall 8 according to the connection position, and performing fire correction with different parameters, the fire correction of inner deck 7 includes: maintaining the distance between the heating line and the nozzle cooling water at no more than 100mm during heating correction, the heating temperature at 890°C to 910°C, and the heating width at no more than 40mm.

[0070] Thus, the above parameters can meet the performance requirements of the inner deck 7.

[0071] Specifically, when a region 5 to be corrected has both concave and convex deformations, the fire correction of the inner deck 7 also includes: first heating the concave and convex areas, with the heating path 6 being short lines, and then heating the convex areas.

[0072] Thus, the convex and concave deformation areas are usually closely adjacent. If a long heating line is used, it will cover both the convex and concave areas at the same time, causing the convex or concave areas to be aggravated. Short lines can be flexibly selected according to the needs of the convex or concave areas.

[0073] In this embodiment, after the heating and straightening process is completed on the back of each rib of the deck, if there are still uneven areas, straightening needs to be performed within the spaces of the area to be straightened, 5. For example... Figure 5 As shown, correction can be achieved by heating a relatively long line in a localized area, followed by heating a shorter line within the space. The short line correction sequence from left to right is 6, 1, 7, 3, 5, 2, 4. Ensure that there is at least one heating distance between each two adjacent heating intervals.

[0074] For the inner wall 8 of the superstructure 1, the inner wall 8 plate is relatively thin. When heating, the heating temperature must be controlled, and the heating width must also be determined by the size of the wall deformation in order to achieve a better correction effect.

[0075] Specifically, in the step of dividing several thin plates into outer deck 4, inner deck 7, outer wall and inner wall 8 according to the connection position, and performing fire correction using different parameters, the fire correction of the inner wall 8 includes: maintaining the distance between the heating line and the nozzle cooling water at 45mm to 55mm during heating correction, the heating temperature at 690°C to 710°C, and the heating width at 25mm to 35mm.

[0076] Thus, the above parameters can meet the performance requirements of the inner wall 8.

[0077] In this embodiment, if the deformation of the inner wall 8 is not significant, the heating temperature and heating width can be appropriately reduced, and the heating speed can be appropriately increased. Figure 6 As shown, the heating sequence of the area to be corrected 5 from left to right is 14253. During the correction heating, because the relative deformation at the connection between the inner wall 8 and the upper and lower decks is small, such as Figure 7 As shown, during correction, a gap of about 150mm can be left between the inner wall 8 and the upper and lower edges (as indicated by the arrows) to avoid the need for heating correction. Moreover, when heating reaches the upper and lower edges, the heating speed can be appropriately accelerated.

[0078] Furthermore, after each area 5 of the inner wall 8 to be corrected is corrected, if the flatness still does not meet the requirements, a second hot-heat correction can be performed in the original position. If the requirements are still not met, short lines of heat or dots of heat can be used to correct the unevenness of the gaps in the area 5 to be corrected, followed by hammering. Figure 8 As shown in the diagram, the small circles represent the hammering points. Preferably, the correction is performed using both short-line heating and hammering methods. The short-line and dot-shaped heating and hammering correction methods also begin from the protruding areas.

[0079] For the outer wall of the superstructure 1, since the outer wall is exposed, the flatness requirement is relatively high.

[0080] Specifically, in the step of dividing several thin plates into outer deck 4, inner deck 7, outer wall and inner wall 8 according to the connection position, and performing fire correction using different parameters, the fire correction of the outer wall includes: maintaining the distance between the heating line and the nozzle cooling water at 45mm to 55mm during heating correction, the heating temperature at 940°C to 960°C, and the heating width determined according to the amount of deformation.

[0081] Therefore, the above parameters can meet the performance requirements of the outer wall.

[0082] In this embodiment, for minor deformation (deformation δ ≤ 3 mm / ㎡), the heating width is generally 15-25 mm (approximately 2-3 times the plate thickness). For moderate deformation (deformation 3 mm < δ ≤ 8 mm / ㎡), the heating width is generally 30-50 mm (approximately 4-7 times the plate thickness). For severe deformation (deformation δ > 8 mm / ㎡), the heating width is generally 50-80 mm (approximately 7-11 times the plate thickness).

[0083] If unevenness still exists after correction, further correction operations can be performed on the inner wall 8. This can be done by heating the back of the outer wall where the structural component 3 is located with long, linear heating lines on both sides of the weld seam near the structural component 3, while cooling the side with the structural component 3 with water. If the correction requirements are still not met, heating can be applied directly to both sides of the weld seam, while cooling the side with the structural component 3 with water for correction.

[0084] For the correction of deformation at the openings of doors and windows on the inner and outer walls, such as Figure 9 As shown, the four corners of the door and window openings 9 can be corrected by using a triangular-shaped heating water cooling method. The length and width of the triangular heating shape can be determined according to the deformation of the door and window edges, and this embodiment does not impose any limitations.

[0085] 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 straightening thin plates in a ship, wherein the thin plate comprises a plate body and a plurality of structural members welded at intervals to the inner surface of the plate body, the plurality of thin plates being connected to form a superstructure, characterized in that, The method for straightening thin plates on ships includes the following steps: The thin plates of the superstructure are straightened in a bottom-up order; On the back side of the plate where the structural member is provided, the plate is divided into several areas to be corrected by each pair of adjacent structural members; Each of the areas to be corrected is sequentially subjected to heat treatment; Two adjacent regions to be corrected in order are separated by at least one region to be corrected in position.

2. The method of claim 1, wherein The ship thin plate straightening method also includes: At the heating position, the heating starting point is located near the edge of the area to be corrected; In the heating direction, the structural member is heated in a long linear shape along its extension direction; In terms of heating sequence, the concave areas are heated first, followed by the convex areas.

3. The method of claim 2, wherein During repeated heating, the heating starting point is adjusted within a range of 10 to 20 mm away from the structural component in the area to be corrected.

4. The method for straightening thin plates of ships as described in claim 1, characterized in that, The method for straightening thin plates of ships also includes the following steps: The thin plates are divided into outer deck, inner deck, outer wall and inner wall according to the connection position, and are pyrotechnically corrected using different parameters.

5. The method for straightening thin plates of ships as described in claim 4, characterized in that, In the step of dividing the several thin plates into outer deck, inner deck, outer perimeter wall, and inner perimeter wall according to their connection positions, and performing pyrotechnic straightening on each according to different parameters, the pyrotechnic straightening of the outer deck includes: During heat correction, maintain a distance of 45mm to 55mm between the heating path and the spray cooling water, the heating temperature should be less than 900°C, the heating width should not exceed 30mm, and the heating depth should be 2 / 3 of the plate thickness.

6. The method of claim 4, wherein In the step of dividing the several thin plates into outer deck, inner deck, outer perimeter wall, and inner perimeter wall according to their connection positions, and performing pyrotechnic straightening on each using different parameters, the pyrotechnic straightening of the inner deck includes: During heating correction, the distance between the heating line and the nozzle cooling water should not exceed 100mm, the heating temperature should be 890°C to 910°C, and the heating width should not exceed 40mm.

7. The method of claim 6, wherein When one of the areas to be corrected has both concave and convex deformations, the pyrotechnic straightening of the inner deck also includes: First, heat the areas with alternating concave and convex surfaces, using short, linear heating paths, and then heat the convex areas.

8. The method of claim 4, wherein In the step of dividing the several thin plates into outer deck, inner deck, outer perimeter wall, and inner perimeter wall according to their connection positions, and performing fire-forming straightening on each using different parameters, the fire-forming straightening of the inner perimeter wall includes: During heating correction, maintain a distance of 45mm to 55mm between the heating line and the nozzle cooling water, a heating temperature of 690°C to 710°C, and a heating width of 25mm to 35mm.

9. The method of claim 4, wherein In the step of dividing the thin plates into outer deck, inner deck, outer wall and inner wall according to the connection position, and performing fire correction with different parameters, the fire correction of the outer wall includes: maintaining the distance between the heating line and the nozzle cooling water at 45mm to 55mm during heating correction, and the heating temperature at 940°C to 960°C.

10. The method of claim 4, wherein The step of straightening the thin plate of the superstructure in a bottom-up order specifically includes: First, straighten the first layer of thin plates, then straighten the inner deck, outer deck, inner wall, and outer wall in sequence. After the first layer is straightened, straighten the next layer in the same order.

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