Plated steel sheet, plated steel sheet manufacturing apparatus, and manufacturing method

Abstract

In one embodiment of the present invention, a coated steel sheet is provided, comprising: a first coated steel sheet region extending along a first direction and including a first steel sheet region and a first coated region; and a second coated steel sheet region extending along the first direction and including a second steel sheet region and a second coated region, the second coated steel sheet region including: a first end portion continuous with the first coated steel sheet region; a second end portion formed in a direction opposite to the first end portion; a pressing portion formed on the upper or lower surface of the second coated region, pressed inward along the second direction, and having a pressing depth; and a cutting portion disposed at the second end portion of the second coated steel sheet region and extending along the second direction, the width of the second coated steel sheet region being greater than the pressing depth.

Description

Technical Field

[0001] This invention relates to a coated steel sheet, a coated steel sheet manufacturing apparatus, and a manufacturing method. Background Technology

[0002] In the cutting process of galvanized steel sheets, a straight-shaped blade is used. To prevent corrosion of the cut surface when using this blade, current techniques include: employing modified blades that push the coating downwards and adhere sparingly to the cut surface during cutting, thus delaying corrosion; or arranging upper / lower blades along the vertical line of the steel sheet to push the coating downwards to the cut surface. However, while these techniques can improve the corrosion resistance of cut surfaces of sheet-like galvanized steel sheets, they are limited in their application to coil-like galvanized steel sheets. Furthermore, changing the blade shape from straight to round for cutting coil-like galvanized steel sheets results in a shorter blade life and a rougher, less smooth cut surface, thus promoting corrosion.

[0003] On the other hand, for the cut surfaces of galvanized steel sheets, the sacrificial corrosion protection of the coating plays a crucial role in corrosion prevention. Furthermore, the coating reacts with corrosive substances to produce corrosion products. These products flow to the cut surfaces of the galvanized steel sheet via water droplets or rainwater formed on the coating surface and accumulate in the corroded areas, thus also providing barrier-based corrosion protection.

[0004] The sacrificial and barrier corrosion protection of cut surfaces achieved through coating increases with the thinner the coated steel sheet and the thicker the coating. If the corrosion resistance of the cut surfaces of the coated steel sheet is improved, the lifespan of the component will also increase. However, depending on the application of the coated steel sheet, a certain thickness needs to be maintained to ensure rigidity. Therefore, it is not only impossible to reduce the thickness below a certain level, but also, due to limitations in the coating amount imposed by the manufacturing process of the coated steel sheet, it is difficult to achieve a coating amount exceeding a certain threshold. Summary of the Invention

[0005] (a) Technical problems to be solved The present invention is proposed to solve the above-mentioned problems, and its purpose is to provide a coated steel sheet, a coated steel sheet manufacturing apparatus and a manufacturing method, wherein by reducing the thickness of the coated steel sheet, the area of ​​the steel sheet exposed through the cut surface is minimized, thereby suppressing rusting of the cut surface.

[0006] (II) Technical Solution To achieve the above objectives, a coated steel sheet according to an embodiment of the present invention may include: a first coated steel sheet region extending along a first direction and including a first steel sheet region and a first coated region; and a second coated steel sheet region extending along the first direction and including a second steel sheet region and a second coated region, the second coated steel sheet region including: a first end continuous with the first coated steel sheet region; a second end formed in a direction opposite to the first end; a pressing portion formed on the upper or lower surface of the second coated region, pressed inward along a second direction, and having a pressing depth; and a cutting portion disposed at the second end of the second coated steel sheet region and extending along the second direction, the width of the second coated steel sheet region being greater than the pressing depth.

[0007] In an embodiment of the present invention, the pressing depth of the pressing portion may vary along the first direction.

[0008] In an embodiment of the present invention, the pressing depth of the pressing portion can gradually increase from the first end of the second coated steel plate region toward the second end along the first direction.

[0009] In an embodiment of the present invention, the press-in portion may be a shape that bends inward toward the second coated steel plate region.

[0010] In an embodiment of the present invention, the slope of the tangent of the press-in portion can change along the first direction between the first end and the second end of the second coated steel plate region.

[0011] In an embodiment of the present invention, the average slope of the tangent between the center portion between the first end and the second end of the second coated steel plate region and the second end is less than or equal to 45°.

[0012] In an embodiment of the present invention, the pressed portion may have a minimum radius of curvature at the second end of the second coated steel plate region and a maximum radius of curvature at the first end of the second coated steel plate region.

[0013] In an embodiment of the present invention, the minimum radius of curvature may be 0.25 mm.

[0014] In an embodiment of the present invention, the thickness of the second coated steel plate region may be 10% to 90% of the thickness of the first coated steel plate region.

[0015] In an embodiment of the present invention, the second plating area may have a first thickness at the first end of the second plating steel plate area and a second thickness less than or equal to the first thickness at the second end of the second plating steel plate area.

[0016] In an embodiment of the present invention, the plated steel sheet may further include: a third plated area extending along the second direction to cover at least a portion of the cut portion.

[0017] In an embodiment of the present invention, the thickness of the third plating region may be less than the thickness of the second plating region.

[0018] In an embodiment of the present invention, the plating amount of the third plating area may be less than the plating amount of the second plating area.

[0019] In an embodiment of the present invention, the density of the second plating region may be greater than the density of the first plating region.

[0020] In an embodiment of the present invention, the density of the second steel plate region may be greater than the density of the first steel plate region.

[0021] In embodiments of the present invention, the width of the press-in portion may be from 0.25 mm to 4 mm.

[0022] In an embodiment of the present invention, the second plated steel sheet region may include: a first pressing portion recessed from the upper surface of the second plated region to the lower side; and a second pressing portion disposed facing the first pressing portion and recessed from the lower surface of the second plated region to the upper side.

[0023] A method for manufacturing a coated steel sheet according to an embodiment of the present invention may include the following steps: supplying a coated steel sheet including a first coated steel sheet region, the first coated steel sheet region including a first coated region and a first steel sheet region; performing a pressing process on the coated steel sheet to form a second coated steel sheet region, the second coated steel sheet region extending along a first direction and including a second coated region and a second steel sheet region; and forming a cut portion extending along a second direction in the second coated steel sheet region.

[0024] In an embodiment of the present invention, during the step of forming the second coated steel plate region, a pressing portion may be formed, the pressing portion being recessed into the inner side of the second coated region along the second direction, and the width being greater than the pressing depth.

[0025] In an embodiment of the present invention, the pressing pressure applied to the second plating area can be 5 kg / cm. 2 Up to 300kg / cm 2 .

[0026] In an embodiment of the present invention, in the step of forming the cutting portion, the cutting portion may be formed to pass through the center of the pressing portion.

[0027] In an embodiment of the present invention, during the step of forming the cut portion, a third plating area may be further formed, the third plating area extending along the second direction and covering at least a portion of the cut portion.

[0028] (III) Beneficial Effects According to an embodiment of the present invention, after the galvanized steel sheet is press-fitted at the cutting target location to reduce its thickness, the press-fitted portion is then cut, thereby minimizing the area of ​​the steel sheet exposed to the outside due to the cutting process. Thus, by delaying the rusting time of the cut portion, the galvanized steel sheet can maintain improved corrosion resistance even after cutting.

[0029] Furthermore, during the pressing process, the inwardly curved pressing portion formed on the clad steel sheet prevents damage such as coating loss or peeling compared to existing pressing processes using sharp-shaped structures. Moreover, by applying pressure using a curved pressure section corresponding to the pressing portion during pressing, areas with drastically reduced thickness and coating amount within the pressing portion are prevented, thereby further improving the corrosion resistance of the clad steel sheet. Attached Figure Description

[0030] Figure 1 This is a perspective view showing a portion of a plated steel sheet according to an embodiment of the present invention.

[0031] Figure 2 This shows a side view. Figure 1 A cross-sectional view of the galvanized steel sheet.

[0032] Figure 3 This shows a side view. Figure 1 A cross-sectional view of the galvanized steel sheet.

[0033] Figure 4 This is a cross-sectional view showing a portion of a galvanized steel sheet as viewed from the side according to another embodiment of the invention.

[0034] Figure 5a This is a cross-sectional view showing a portion of a plated steel sheet before cutting, according to yet another embodiment of the present invention.

[0035] Figure 5b It shows the... Figure 5a A cross-sectional view of a galvanized steel sheet after it has been cut and processed.

[0036] Figure 6 The diagram schematically shows the appearance of a coated steel sheet before it is pressed into place by the coated steel sheet manufacturing apparatus according to the present invention.

[0037] Figure 7The diagram schematically illustrates a galvanized steel sheet manufacturing apparatus according to an embodiment of the present invention performing a pressing process on a galvanized steel sheet.

[0038] Figure 8 The diagram schematically illustrates a coated steel sheet manufacturing apparatus according to another embodiment of the present invention performing a pressing process on a coated steel sheet.

[0039] Figure 9 The pressing section of the pressing unit according to an embodiment of the present invention is shown. Figure 9 The enlarged view of the lower side shows the pressurization section according to another embodiment of the present invention.

[0040] Figure 10a The pressurization section of another pressurization unit of the present invention is shown.

[0041] Figure 10b The pressurization section of another pressurization unit of the present invention is shown.

[0042] Figure 11 It is a cross-sectional view showing the plated steel sheet after the pressing process is completed and before it is cut.

[0043] Figure 12 The diagram schematically shows the appearance of a galvanized steel sheet before it is pressed into place by an apparatus for manufacturing galvanized steel sheets according to yet another embodiment of the present invention.

[0044] Figure 13 schematically shown Figure 11 The pattern of a steel plate processing device pressing a galvanized steel plate.

[0045] Figure 14a The image shows a plated steel sheet before it is cut.

[0046] Figure 14b This shows a plated steel sheet with a cut section formed by cutting.

[0047] Figure 15 The diagram schematically illustrates the state of the coated steel sheet according to the present invention after the cutting process is completed and before the pressing process begins.

[0048] Figure 16 It is an enlarged cross-sectional view showing a portion of a galvanized steel sheet manufactured after cutting and pressing processes. Detailed Implementation

[0049] Hereinafter, preferred embodiments will be described in detail with reference to the accompanying drawings, enabling those skilled in the art to readily implement the present invention. However, in describing the preferred embodiments in detail, detailed descriptions of related well-known functions or configurations will be omitted if it is believed that such descriptions might obscure the essence of the invention. Furthermore, the same reference numerals are used throughout the drawings for parts that perform similar functions and effects. Additionally, in this specification, terms such as "upper," "upper part," "above," "lower," "lower part," "below," and "side" are based on the drawings and may actually vary depending on the arrangement direction of the components.

[0050] Furthermore, throughout the specification, when one part is "connected" to another, this includes not only "direct connection" but also "indirect connection" where other components are intervening. Additionally, when a component is "included," unless specifically stated otherwise, it means that other components may be included, rather than excluded.

[0051] Figure 1 This is a perspective view showing a portion of a plated steel sheet according to an embodiment of the present invention.

[0052] Reference Figure 1 According to one embodiment of the present invention (hereinafter, Embodiment 1), the plated steel sheet 10 may include a steel sheet 11 and a coating 12. The steel sheet 11 may have a plate shape.

[0053] As an example, the clad steel sheet 10 can be manufactured by forming a coating 12 on a steel sheet 11, pressing a portion of the coating 12, and then cutting it to a predetermined length. As another example, the clad steel sheet 10 can be manufactured by forming a coating 12 on a steel sheet 11, cutting the clad steel sheet 10 to a predetermined length, and then pressing the cut portion (hereinafter, the cut portion) 14. In this case, the clad steel sheet 10 can be cut to various lengths depending on its intended use.

[0054] The coating 12 can be formed on the steel plate 11. In this case, the coating 12 can improve the corrosion resistance and durability of the steel plate 11 by partially wrapping the outer surface of the steel plate 11.

[0055] For example, zinc can be used as the plating material to form coating 12. Alternatively, small amounts of aluminum and magnesium can be added to zinc to form coating 12. In this case, coating 12 can be configured to contain 10% to 15% aluminum, 4% to 6% magnesium, and 79% to 86% zinc, but is not limited thereto. On the other hand, coating 12 can be formed by electroplating or hot-dip galvanizing.

[0056] The coating 12 may include a first coating portion 12a covering the upper surface of the steel plate 11 and a second coating portion 12b covering the lower surface of the steel plate 11. Therefore, the coating 12 can be formed on both the upper and lower surfaces of the steel plate 11. According to an embodiment, the coating 12 may not be formed on the side surface 11a of the steel plate 11. According to another embodiment, the coating 12 may extend partially onto the side surface 11a of the steel plate 112, thereby forming a partial coating.

[0057] Figure 2 Showing a side view Figure 1 The appearance of the galvanized steel sheet.

[0058] Reference Figure 2 The galvanized steel sheet 10 may include a first galvanized steel sheet region A10 and a second galvanized steel sheet region A20.

[0059] The first coated steel plate area A10 may include the first steel plate area A11 and the first coated area A12.

[0060] The first steel plate region A11 may be a plate shape extending along the first direction B1 and having the same or similar thickness. In this case, the first steel plate region A11 may include a portion of a steel plate A21 whose thickness is reduced by pressing. In this case, the portion of the steel plate A21 with reduced thickness may be provided at the portion connected to the second steel plate region A21 described later.

[0061] The first plating area A12 is the area of ​​the plating layer 12 that is not directly subjected to pressing processing, and can be formed on the first steel plate area A11. More specifically, the first plating area A12 can cover the upper and lower surfaces of the first steel plate area A11. In this case, the first plating area A12 may not be formed on the two side surfaces 11a of the first steel plate area A11, or only a portion of it may be formed.

[0062] The second coated steel sheet region A20 is the region in the coated steel sheet 10 where the pressing process is performed, and it can be continuously provided with the first coated steel sheet region A10. More specifically, the first end E1 of the second coated steel sheet region A20 can be continuous with the first coated steel sheet region A10. Furthermore, the second end E2 of the second coated steel sheet region A20 can be formed in a region extending along a first direction B1 towards the opposite side of the first coated steel sheet region A10. Here, the first direction B1 is the width direction of the coated steel sheet 10, which can be a direction parallel to the Y-axis direction in the accompanying drawings. A cutting portion 14 is formed at the second end E2 of the second coated steel sheet region A20, which will be described later.

[0063] The second coated steel plate region A20 may include a second steel plate region A21 and a second coated region A22. The second coated region A22 may be formed on the upper and lower surfaces of the second steel plate region A21. In this case, the second coated regions A22 may not be formed on the two side surfaces 11a of the second steel plate region A21, or only a portion of them may be formed.

[0064] The second coated steel sheet region A20 may include a pressing portion 13 and a cutting portion 14. The pressing portion 13 can be formed by the pressing process described above. The pressing portion 13 may be recessed inward from one surface of the second coated region A22. The one surface of the second coated region A22 may be one of the upper surface and the lower surface of the second coated region A22. Therefore, the pressing portion 13 may be formed by pressing inward to a depth P1 along the second direction B2 on the upper and lower surfaces of the second coated region A22. Here, the second direction B2 is the thickness direction of the coated steel sheet 10, which may be a direction parallel to the Z-axis direction in the figure.

[0065] The pressing depth P1 can vary depending on the width direction (i.e., the first direction) B1 of the pressing portion 13. More specifically, the pressing depth P1 can gradually increase from the first end E1 of the second coated steel plate region A20 along the first direction B1 toward the second end E2. In this case, the pressing depth P1 of the pressing portion 13 can be minimum at the first end E1 and maximum at the second end E2.

[0066] As an example, the press-in portion 13 may have a shape that curves inward toward the second coated steel plate region A20. In this case, when viewed from the side direction (e.g., the YZ plane direction), the press-in portion 13 may extend in a curved shape along the first direction B1. At this time, the width L1 of the press-in portion 13 may be greater than the pressing depth P1. Therefore, the curved press-in portion 13 may have a minimum radius of curvature at the second end E2 of the second coated steel plate region A20 and a maximum radius of curvature at the first end E1 of the second coated steel plate region A20. For example, the minimum radius of curvature may be 0.25 mm, and in this case, the radius of curvature of the press-in portion 13 may be greater than or equal to 0.25 mm.

[0067] Because it is formed in a curved shape, the slope θ of the tangent TL of the pressing portion 13 can vary along the first direction B1. More specifically, the slope θ of the tangent TL can be minimized at the second end E2 of the second coated steel plate region A20 where the pressing depth P1 is the largest. At this time, the slope θ of the tangent TL can gradually increase along the first direction B1 toward the first end E1 of the second coated steel plate region A20. Therefore, the slope θ of the tangent TL can be maximized at the first end E1 of the second coated steel plate region A20 where the pressing depth P1 is the smallest. At this time, with the first direction B1 as a reference, the slope of the tangent TL at the center C' of the pressing portion 13 can have a value between the maximum slope and the minimum slope. In this case, the pressing portion 13 can be formed such that the average slope of the tangent TL from the second end E2 of the second coated steel plate region A20 to the center C' of the pressing portion 13 is less than or equal to 45°.

[0068] The second plated steel sheet region A20 may include two press-in portions 13. In this case, one of the two press-in portions 13 (hereinafter, the first press-in portion) 13a may be formed recessed from the upper surface of the second plated region A22 toward the lower side. The other one of the two press-in portions 13 (hereinafter, the second press-in portion) 13b may be formed recessed from the lower surface of the second plated region A22 toward the upper side. At this time, the first press-in portion 13a and the second press-in portion 13b may be arranged facing each other along the second direction B2.

[0069] On the other hand, for ease of explanation, the description will focus on the case where the first pressing part 13a and the second pressing part 13b are recessed in opposite directions but have the same shape and size, but the present invention is not limited thereto.

[0070] The cutting section 14 can cut the object CP of the plated steel sheet 10 (see reference). Figure 6 It is formed by cutting along the cutting direction. At this time, the cutting direction can be a direction parallel to the second direction B2.

[0071] As an example, the cutting section 14 can be modified after the pressing process is completed by adjusting the pressing sections 13AA and 13BB ( Figure 8 The cutting portion 14 is formed by cutting along the pre-cut pressing portions 13AA and 13BB. Figure 9 The cutting portion 14 is formed by cutting along the center C of the first pressing portion 13AA and the second pressing portion 13BB before cutting, and in a direction parallel to the second direction B2. Alternatively, if two pressing portions 13 are provided, the cutting portion 14 can be formed by cutting along the common center C of the first pressing portion 13AA and the second pressing portion 13BB before cutting, and in a direction parallel to the second direction B2. As described above, by performing the cutting process, the cutting portion 14 can be provided at the second end E2 of the second plated steel sheet region A20 in the plated steel sheet 10 after the cutting process is completed.

[0072] Furthermore, when viewed from the side (e.g., in the ZX plane direction) along the first direction B1, a steel plate 11 may be provided in the middle region 14a of the cut portion 14. Additionally, a plating layer 12 may be provided in the edge region 24b surrounding the middle region 14a of the cut portion 14. Through the middle region 14a of the cut portion 14, a portion of the second steel plate region A21 may be exposed to the outside.

[0073] As another example, the cutting portion 14 can be formed before the pressing portion 13. In this case, when the cutting process of the galvanized steel sheet 10 is completed, the pressing process can be performed with the formed cutting portion 14 as the center. Thus, the pressing portion 13 can be formed. At this time, the specific features of the pressing portion 13 and the cutting portion 14 are the same as or similar to those described above, so repeated descriptions will be omitted.

[0074] Figure 3 This shows a side view. Figure 1 A cross-sectional view of the galvanized steel sheet.

[0075] Reference Figure 3 The thickness of the second coated steel plate region A20 can be less than or equal to the thickness T1 of the first coated steel plate region A10. Since a pressing part 13 is formed in the second coated steel plate region A20 with a pressing depth P1 that varies along the first direction B1, the thickness of the second coated steel plate region A20 can also vary along the first direction B1.

[0076] More specifically, the second clad steel plate region A20 can have its maximum thickness at the first end E1. Furthermore, the thickness of the second clad steel plate region A20 gradually decreases along the first direction B1 towards the second end E2, thereby having a minimum thickness (2T2a+T3a) at the second end E2. In this case, the maximum thickness of the second clad steel plate region A20 can be the same as the thickness T1 of the first clad steel plate region A10. Therefore, between the first end E1 and the second end E2, the thickness of the second clad steel plate region A20 can be less than the thickness T1 of the first clad steel plate region A10. The thickness (i.e., the minimum thickness) of the second clad steel plate region A20 at the second end E2 can be 10% to 90% of the thickness T1 of the first clad steel plate region A10.

[0077] Furthermore, during the pressing process, the steel plate 11 can also be pressed in together with the plating layer 12, thereby reducing its thickness. In this case, the first steel plate region A11 can have the minimum thickness T3a at the second end E2 where the pressing depth P1 is the greatest. In this case, the second end E2 is the part where the cutting portion 14 is formed, and the thickness T3a of the first steel plate region A11 in the cutting portion 14 will be the minimum. As a result, the area of ​​the steel plate 11 exposed to the outside through the cutting portion 14 can be minimized.

[0078] The width of the second coated steel sheet region A20 can be greater than the pressing depth P1 of the pressing portion 13. In this case, the width of the second coated steel sheet region A20 can be the same as the width L1 of the pressing portion 13. Therefore, the pressing portion 13 can be in a form where the width L1 is greater than the pressing depth P1. For example, the width L1 of the pressing portion 13 can be from 0.25 mm to 4 mm.

[0079] As described above, since the pressing process is performed only on the second coated steel sheet region A20, the density of the second coated region A22 can be greater than the density of the first coated region A12. This may be because the pressing process is performed only on a portion of the coating 12 that has the same or similar thickness before the pressing process, namely the second coated region A22, by applying pressure in the vertical direction Z toward the inside of the coated steel sheet 10.

[0080] In addition, during the pressing process, since a portion of the steel plate 11 corresponding to the second steel plate region A21 is pressed together, the density of the second steel plate region A21 can be greater than the density of the first steel plate region A11.

[0081] The thickness of the second plating region A22 formed by the pressing process can be less than the thickness T2 of the first plating region A12 that was not pressed in. As described above, since the slope θ and radius of curvature of the tangent TL at the second end E2 of the second plating steel plate region A20 of the bent pressing portion 13 are the smallest, the second plating region A22 can maintain a predetermined thickness T2a at the second end E2. That is, since the pressing portion 13 is pressed in a bent form, damage or peeling of the plating layer 12 at the second end E2 of the second plating steel plate region A20 can be prevented during the pressing process.

[0082] For example, the thickness of the second plating region A22 can be the same or similar throughout the length direction (first direction) B1 of the second plating region A22, but the present invention is not limited thereto. As another example, the thickness of the second plating region A22 at the second end E2 (second thickness) can be less than the thickness at the first end E1 (first thickness). According to an embodiment, the second plating region A22 has the maximum thickness at the first end E1, and the thickness gradually decreases along the first direction B1 toward the second end E2, so that the thickness T2a at the second end E2 can be the minimum. At this time, the density of the second plating region A22 can be the maximum at the second end E2 with the minimum thickness, and the minimum density at the first end E1 with the maximum thickness.

[0083] Figure 4 This is a cross-sectional view showing a portion of a galvanized steel sheet as viewed from the side according to another embodiment of the invention.

[0084] Reference Figure 4 According to another embodiment of the present invention (hereinafter, Embodiment 2), the plated steel sheet 10A may include a first plated steel sheet region A10 and a second plated steel sheet region A20. Since their specific features are the same as or similar to those of Embodiment 1 described above, repeated descriptions will be omitted. In addition, the plated steel sheet 10A according to Embodiment 2 may further include a third plated region A30.

[0085] The third plating region A30 can be provided in the cutting portion 14. The third plating region A30 can be formed to cover at least a portion of the cutting portion 14. In this case, the third plating region A30 can be continuous with the second plating region A22 and extend along the second direction B2.

[0086] Since the pressing portions 13 are respectively formed at the upper and lower ends of the second coated steel sheet region A20, the coated steel sheet 10A can include two third coated regions A30. In this case, with reference to the second direction B2, the upper third coated region (hereinafter, the upper third coated region) A31 can be connected to the second coated region (hereinafter, the upper second coated region) A22 provided at the upper end of the second coated steel sheet region A20. More specifically, the upper end of the upper third coated region A31 can be connected to the upper second coated region A22, and the lower end of the upper third coated region A31 can extend downward along the second direction B2.

[0087] Furthermore, with reference to the second direction B2, the lower third plating area (hereinafter, the lower third plating area) A32 can be connected to the lower plating area (hereinafter, the lower second plating area) A22 located at the lower end of the second plating steel plate area A20. More specifically, the lower end of the lower third plating area A32 can be connected to the lower second plating area A22, and the upper end of the lower third plating area A32 can extend upward along the second direction B2.

[0088] As an example, the upper third plating region A31 and the lower third plating region A32 can be connected to each other. In this case, the lower end of the upper third plating region A31 and the upper end of the lower third plating region A32 can be at least partially continuous. As another example, the lower end of the upper third plating region A31 and the upper end of the lower third plating region A32 can also be spaced apart from each other.

[0089] As described above, the third plating region A30 can be formed during the cutting process of the plating sheet 10 by moving a portion of the plating component contained in the second plating region A22. Therefore, the plating amount of the second plating region A30 can be less than the plating amount of the second plating region A20. Furthermore, the thickness of the third plating region A30 can be less than the thickness of the second plating region A22. In this case, the thickness of the upper third plating region A31 can gradually decrease from its upper end to its lower end, but as another example, it can also be formed to have the same or similar thickness throughout in the second direction B2. Similarly, the thickness of the lower third plating region A32 can gradually decrease from its lower end to its upper end, but as another example, it can also be formed to have the same or similar thickness throughout in the second direction B2.

[0090] Figure 5a This is a cross-sectional view showing a portion of a plated steel sheet before cutting, according to yet another embodiment of the present invention. Additionally, Figure 5b It shows the... Figure 5a A cross-sectional view of a galvanized steel sheet after it has been cut and processed.

[0091] Reference Figure 5a and Figure 5b According to another embodiment of the present invention (hereinafter, Embodiment 4), the plated steel sheet 10B may include a first plated steel sheet region A10 and a second plated steel sheet region A20. In this case, the specific features of the first plated steel sheet region A10 are the same as or similar to those of Embodiment 1 described above, so repeated descriptions will be omitted, and the description will focus on the differences.

[0092] like Figure 5a As shown, after the pressing process is completed, the pressing portion 13AA can be formed only at the upper end of the galvanized steel sheet 10B. At this time, the pressing portion 13AA is a pressing portion before cutting, and can have a wider width 2L1 than the pressing portion 13 after cutting. In this case, the lower end of the galvanized steel sheet 10B can be a flat shape without the pressing process performed.

[0093] In the case of 10B plated steel sheet that has completed cutting and processing, such as Figure 5b As shown, the second plated steel sheet region A20 may include a press-in portion 13. In this case, since only one press-in portion 13 is formed, the cut portion 14A may have a thickness T3A different from that of Embodiment 1 or Embodiment 2. In addition, the area of ​​the second steel sheet region A21 exposed to the outside through the cut portion 14A may also be different from that of Embodiment 1 or Embodiment 2. However, in the case of the plated steel sheet 10A according to Embodiment 3, similarly, since the press-in portion 13 with an inwardly bent shape is formed in the second plated steel sheet region A20, the area of ​​the steel sheet 11 exposed to the outside is reduced after the cutting process, thereby delaying the rusting time of the cut portion 14A.

[0094] On the other hand, in the above embodiments, for ease of explanation, each region of the clad steel plates 10, 10A, and 10B is distinguished and referred to, but the first clad steel plate region A10 and the second clad steel plate region can represent each region of a single clad steel plate 10, 10A, and 10B.

[0095] Figure 6 The diagram schematically shows the appearance of a coated steel sheet before it is pressed into place by the coated steel sheet manufacturing apparatus according to the present invention. Figure 7 The diagram schematically illustrates a galvanized steel sheet manufacturing apparatus according to an embodiment of the present invention performing a pressing process on a galvanized steel sheet. Figure 8 The diagram schematically illustrates a coated steel sheet manufacturing apparatus according to another embodiment of the present invention performing a pressing process on a coated steel sheet. Figure 9 The pressing section of the pressing unit according to an embodiment of the present invention is shown. Figure 9 The enlarged view of the lower side shows the pressurization section according to another embodiment of the present invention. Figure 10a The pressurizing section of another pressing unit of the present invention is shown. Additionally, Figure 10b The pressurizing section of another pressing unit of the present invention is shown. Additionally, Figure 11 It is a cross-sectional view showing the plated steel sheet after the pressing process is completed and before it is cut.

[0096] Reference Figures 6 to 11 Before the cutting process of the galvanized steel sheet 10, the galvanized steel sheet manufacturing apparatus 20 can perform a pressing process on a portion of the galvanized steel sheet 10. This forms the pressing portion 13. Hereinafter, for ease of explanation, the description will focus on the case where the galvanized steel sheet 10 according to Example 1 is manufactured by the galvanized steel sheet manufacturing apparatus 20, but it is not limited thereto.

[0097] The plated steel sheet 10, which is the object of the pressing process, may include a steel sheet 11 and coatings 12a and 12b covering the outer surface of the steel sheet 11. As an example, the plated steel sheet 10 is a ternary plated steel sheet, in which case the coatings 12a and 12b may contain 10% to 15% aluminum, 4% to 6% magnesium, and 79% to 86% zinc, but are not limited thereto.

[0098] According to one embodiment of the present invention (hereinafter, Embodiment 1), the galvanized steel sheet manufacturing apparatus 20 may include a pair of pressing units 100, 200. Hereinafter, one of the pair of pressing units will be referred to as the first pressing unit 100, and the other of the pair of pressing units will be referred to as the second pressing unit 200.

[0099] The first pressing unit 100 and the second pressing unit 200 can be arranged facing each other. As an example, when pressing the galvanized steel sheet 10, the first pressing unit 100 and the second pressing unit 200 can be arranged symmetrically with respect to the galvanized steel sheet 10 as the center. In this case, the first pressing unit 100 can be arranged on the upper side of the galvanized steel sheet 10, and the second pressing unit 200 can be arranged on the lower side of the galvanized steel sheet 10.

[0100] At least one of the first pressing unit 100 and the second pressing unit 200 can be configured to be height-adjustable. As an example, both the first pressing unit 100 and the second pressing unit 200 can be height-adjustable. In this case, the pressing units 100 and 200 can be positioned closer to or further away from each other in the vertical direction shown in the figures, separated by the galvanized steel plate 10.

[0101] As another example, only one of the first pressing unit 100 and the second pressing unit 200 can be configured to be height-adjustable. In this case, one of the pressing units 100 and 200 is in a fixed state, while the other pressing unit 100 and 200 can be height-adjustable. For ease of explanation, the following description will focus on the case where both pressing units 100 and 200 can be height-adjustable.

[0102] The first pressing unit 100 may include a main body (hereinafter, the first main body) 110, a connecting part (hereinafter, the first connecting part) 120, and a pressurizing part (hereinafter, the first pressurizing part) 130.

[0103] The first body 110 is part of other configurations that mount and support the first pressing unit 100, and can be connected to the drive unit (not shown). The first body 110 can be raised and lowered along the first lifting direction D1 using the driving force received from the drive unit.

[0104] The first body 110 can have various forms. More specifically, the first body 110 can be a form that extends along a first direction A1. In this case, the first direction A1 can be a direction parallel to the bottom surface of the building on which the galvanized steel sheet manufacturing apparatuses 20 and 20A are installed (or, the left-right direction in the attached figure), but is not limited thereto. As an example, the first body 110 can be formed into a cylindrical shape that extends along the first direction A1.

[0105] The first connecting portion 120 can be attached to the first main body 110. In this case, the first connecting portion 120 can extend along a second direction A2, which is different from the extending direction of the first main body 110, i.e., the first direction A1. In the accompanying drawings, the second direction A2 is shown to be perpendicular to the first direction A1, but this is only one embodiment. Obviously, the second direction A2 can also be a diagonal line inclined at a predetermined angle relative to the first direction A1. However, for ease of explanation, the description will focus on the case where the second direction A2 is perpendicular to the first direction A1. In this case, the second direction A2 can be parallel to the aforementioned first lifting direction D1.

[0106] The first connecting portion 120 may have a length longer than the thickness of the first body 110. Therefore, both ends (upper and lower ends) of the first connecting portion 120 may protrude from the first body 110 with reference to a first lifting direction D1. More specifically, the first connecting portion 120 may protrude outward from the outer surface of the first body 110. Furthermore, the first connecting portion 120 may be formed to wrap around the outer surface of the first body 110 circumferentially. As an example, if the first body 110 is cylindrical, the first connecting portion 120 may be formed as a ring or a similar shape extending circumferentially around the outer surface of the first body 110.

[0107] During the press-fit process, the first pressing portion 130 can be a portion that directly applies pressure to the upper surface of the plated steel sheet 10. The first pressing portion 130 can be provided in the first connecting portion 120. In this case, the first pressing portion 130 can be in a form that protrudes outward from the outer surface of the first connecting portion 120. The end of the first pressing portion 130 that protrudes outward in this way is referred to as the first outer end portion 130a.

[0108] The first pressurizing portion 130 can cover the outer surface of the first connecting portion 120. More specifically, the first pressurizing portion 130 can extend circumferentially along the first connecting portion 120 to cover the outer surface of the first connecting portion 120. In this case, the first pressurizing portion 130 can extend circumferentially along the first connecting portion 120, with its two ends connected to each other in a ring shape. Therefore, the first outer end portion 130a can also protrude outward from the first connecting portion 120 and extend circumferentially along the first connecting portion 120.

[0109] As an example, the first pressurizing part 130 may be configured independently of the first connecting part 120 and fixedly coupled to the first connecting part 120. As another example, the first pressurizing part 130 may be a protruding form integrally formed with the first connecting part 120.

[0110] At least a portion of the first outer end portion 130a of the first pressurizing portion 130 may have a rounded shape. More specifically, the first outer end portion 130a may be a hemisphere with a circular cross-section. Therefore, the lower surface 131a of the first outer end portion 130a may be a shape that is bent as a whole with a constant curvature.

[0111] The width L2 of the first pressurizing part 130 can be smaller than the width of the first connecting part 120. In this case, the outer surface of the first connecting part 120 can be parallel to the longitudinal direction (first direction) A1 of the galvanized steel sheet 10. Therefore, when the galvanized steel sheet manufacturing apparatus 20 is viewed from the side, as... Figure 9 As shown, at the center of the outer surface of the first connecting portion 120 extending parallel to the first direction A1, the first outer hemispherical end portion 130a can be provided in a shape that protrudes outward. On the other hand, for example, the width L2 of the first pressure portion 130 can be 0.5 mm to 8 mm, but obviously, this can vary depending on the intended use of the coated steel plate 10.

[0112] As another embodiment, such as Figure 9 As exemplarily shown in the lower figure, the first pressurizing portion 130 may further include a protrusion 132a at the first outer end portion 130a. In this case, the protrusion 132a may protrude further outward from the outer surface 131a of the first outer end portion 130a. The protrusion 132a may be formed to extend circumferentially along the first pressurizing portion 130 to enclose the outer surface 131a of the first pressurizing portion 130. At this time, the protrusion 132a may have a hemispherical cross-section with a diameter smaller than the width L2 of the first pressurizing portion 130.

[0113] As described above, since the first pressing portion 130 has a multi-stage structure including a first outer end portion 130a and a protrusion 132a, the galvanized steel sheet 10 can be pressed to a deeper depth. This allows for a further reduction in the thickness T3 of the pressed portion of the galvanized steel sheet 10 (see Figure 10). Furthermore, the protrusion 132a can be formed with a narrower width than the first outer end portion 130a. As described above, by cutting the portion pressed in with a narrower width, the area of ​​the steel sheet 11 exposed to the outside due to the cutting process can be minimized.

[0114] Multiple first pressurizing portions 130 can be provided. In this case, multiple first connecting portions 120, each with a first pressurizing portion 130, can also be provided in the same number as the first pressurizing portions 130. The first connecting portions 120 and the first pressurizing portions 130 provided on the first connecting portions 120 can be spaced apart at predetermined intervals along the length of the first body 110. As an example, the distance between adjacent first pressurizing portions 130 can be the same. However, since the distance between the first pressurizing portions 130 corresponds to the length of the cut coated steel sheet 10, it can be changed according to the intended use of the coated steel sheet 10.

[0115] The second pressing unit 200 can be arranged opposite to the first pressing unit 100. Thus, when the galvanized steel sheet 10 is placed between the first pressing unit 100 and the second pressing unit 200, it can be pressed in by the first pressing unit 100 and the second pressing unit 200.

[0116] The second pressing unit 200 may include a main body (hereinafter, the second main body) 210, a connecting part (hereinafter, the second connecting part) 220 and a pressing part (hereinafter, the second pressing part) 230. Since their specific features are the same or similar to those of the first pressing unit 100 described above, repeated descriptions will be omitted, and the description will focus on the differences.

[0117] The second body 210 is a component of another configuration for mounting the second pressing unit 200, and can be connected to a drive unit (not shown) and operated to move up and down in the second lifting direction D2. The second body 210 may have the same or similar shape as the first body 110. For example, the second body 210 may have a cylindrical shape extending in the first direction A1 described above.

[0118] The second connecting portion 220 can be attached to the second body 210 and extends along a third direction A3, which is different from the first direction A1. As an example, the third direction A3 can be a direction perpendicular to the first direction A1. In this case, the third direction A3 can be a direction that is the same as or parallel to the second direction A2. The invention is not limited thereto, but the following description focuses on the case where the third direction A3 is the same as or parallel to the second direction A2.

[0119] During the press-fit process, the second pressing part 230 can be a part that directly applies pressure to the lower surface of the galvanized steel sheet 10. The second pressing part 230 can be provided in the second connecting part 220. In this case, the second pressing part 230 can be in a form that protrudes outward from the outer surface of the second connecting part 220. The end of the second pressing part 230 that protrudes outward in this way is referred to as the second outer end.

[0120] Since the second connecting portion 220 is formed to extend in the same direction as the first connecting portion 120, the second pressurizing portion 230 can be symmetrically arranged with the first pressurizing portion 130 along the second direction A2 or the third direction A3. In addition, when multiple second pressurizing portions 230 are provided, each second pressurizing portion 230 can be arranged one-to-one with one of the multiple first pressurizing portions 130 provided on the upper side.

[0121] Refer again Figure 6 and Figure 7 According to Embodiment 1, the galvanized steel sheet manufacturing apparatus 20 can be configured such that the first pressing unit 100 and the second pressing unit 200 are rotatable.

[0122] More specifically, the first body 110 of the first pressing unit 100 can rotate about a first rotation axis C1. At this time, the first rotation axis C1 can pass through the center of the first body 110 and extend parallel to the first direction A1. As the first body 110 rotates, the first connecting portion 120 and the first pressing portion 130 can also rotate together. Furthermore, the second body 210 of the second pressing unit 200 can rotate about a second rotation axis C2. At this time, the second rotation axis C2 can pass through the center of the second body 210 and extend parallel to the first direction A1. As the second body 210 rotates, the second connecting portion 220 and the second pressing portion 230 can also rotate together. At this time, the first pressing portion 130 and the second pressing portion 230 can be configured as a pressing roller.

[0123] In this configuration, the galvanized steel sheet 10 can be supplied between the rotating first pressing unit 100 and the second pressing unit 200. At this time, one end of the galvanized steel sheet 10, which is wound in a coil, can be unwound and supplied between the pressing units 100 and 200. The upper and lower ends of the supplied galvanized steel sheet 10 are pressed by the rotating first pressing unit 130 and the second pressing unit 230, thereby performing a pressing process.

[0124] As described above, during the pressing process, one surface (i.e., the upper surface) of the galvanized steel sheet 10 can be pressed downward by the first pressing part 130, while the other surface (i.e., the lower surface) of the galvanized steel sheet 10 can be pressed upward by the second pressing part 230. Thus, a pair of pressing parts 13 can be formed on the galvanized steel sheet 10. Since the first pressing part 130 and the second pressing part 230 are symmetrically arranged, the pair of pressing parts 13 can also be formed in symmetrical positions, with their centers C arranged on the same line.

[0125] Reference Figure 6 and Figure 8According to another embodiment of the present invention (hereinafter, Embodiment 2), the plated steel sheet manufacturing apparatus 20A may include a first pressing unit 100 and a second pressing unit 200. In this case, the features of the pressing units 100 and 200 are mostly the same as or similar to those of Embodiment 1 described above, and therefore the description will focus on the differences.

[0126] The arrangement of the first pressing unit 100 and the second pressing unit 200 relative to each other is the same as in Embodiment 1 described above. In this configuration, the pressing units 100 and 200 can be raised and lowered to move closer to or further away from each other. Before the first pressing unit 100 and the second pressing unit 200 begin to rise or fall towards each other, there are spacer spaces between the pressing units 100 and 200, and the galvanized steel sheet 10 can be supplied into these spacer spaces. At this time, the supplied galvanized steel sheet 10 can be in a flat sheet form. After supplying this galvanized steel sheet 10, the first pressing unit 100 can descend towards the upper surface of the galvanized steel sheet 10, while the second pressing unit 200 can rise towards the lower surface of the galvanized steel sheet 10.

[0127] As described above, when the first main body 110 descends, the first connecting portion 120 and the first pressurizing portion 130 can also descend together. Therefore, the outer surface 131a of the first outer end portion 130a of the first pressurizing portion 130 can contact the upper plating layer 12a of the plated steel sheet 10. In addition, as the second main body 210 rises, the second connecting portion 220 and the second pressurizing portion 230 can also rise together, so that the outer surface of the second outer end portion of the second pressurizing portion 230 contacts the lower plating layer 12b of the plated steel sheet 10.

[0128] Then, as Figure 8 As shown, the first main body 110 descends further, and the second main body 210 can rise further. Therefore, with the outer surface 131a of the first outer end 130a in contact with the upper plating layer 12a, the first pressure-applying part 130 can apply downward pressure to the plated steel sheet 10. Furthermore, with the outer surface of the second outer end in contact with the lower plating layer 12b, the second pressure-applying part 230 can apply upward pressure to the plated steel sheet 10.

[0129] As described above, since the coated steel sheet 10 is pressed in the vertical direction, the upper coating 12a can be pressed in to form an inwardly recessed groove-shaped pressed portion (upper pressed portion) 23, and the lower coating 12b can be pressed in to form an inwardly recessed groove-shaped pressed portion (lower pressed portion) 13.

[0130] As described above, during the pressing process, the upper surface of the galvanized steel sheet 10 is pressed downward by the first pressing part 130, and the lower surface of the galvanized steel sheet 10 is pressed upward by the second pressing part 230, thereby forming a pair of pressing parts 13. At this time, since the first pressing part 130 and the second pressing part 230 are symmetrically arranged, the pair of pressing parts 13 can also be formed in symmetrical positions, so that their centers C are arranged on the same line.

[0131] Figure 10a The pressurizing section of another pressing unit of the present invention is shown. Additionally, Figure 10b The pressurization section of another pressurization unit of the present invention is shown.

[0132] Reference Figure 10a When viewed from the side, the first outer end portion 130b of the first pressurizing portion 130 according to another embodiment of the present invention may have an elliptical cross-section. In this case, the width and protrusion distance of the first outer end portion 130b may differ from those of the first outer end portion 130a having a circular cross-section. For example, the width of the first outer end portion 130b having an elliptical cross-section may be greater than the width of the first outer end portion 130a having a circular cross-section. Furthermore, the first outer end portion 130b may be formed to have a protrusion distance that is shorter than or the same as that of the first outer end portion 130a.

[0133] Reference Figure 10b Viewed from the side, the first outer end portion 130c of the first pressurizing portion 130 according to another embodiment of the present invention may have a quadrilateral cross-section with rounded corners. The width and protrusion distance of this first outer end portion 130b may differ from the first outer end portions 130a and 130b described above. For example, the width of the first outer end portion 130c having a quadrilateral cross-section may be smaller than the width of the first outer end portions 130a and 130b, but is not limited thereto.

[0134] On the other hand, Figure 10a and Figure 10b In this paper, only the first pressurizing part 130 is shown, but the second pressurizing part 230 may also have the same form as the first pressurizing part 130. It is also obvious that pressurizing parts with different forms as described above may be integrated on a galvanized steel sheet manufacturing apparatus 20.

[0135] As described above, since the pressure-applying portions 130 and 230 are formed in a curved shape, or at least at their corners, pressure can be prevented from concentrating on a portion of the plating layers 12a and 12b. This prevents the plating layers 12a and 12b from being torn or falling off during the pressing process, for example, if the pressure-applying portions are sharp, thereby effectively suppressing rusting of the plated steel sheet 10 after cutting.

[0136] On the other hand, when the first and second pressurizing sections 230 press the coated steel sheet 10, a pressure within a predetermined range can be applied. For example, the pressure applied at the start of pressing can be 5 kg / cm². 2 Up to 300kg / cm 2 Within the range, preferably, it can be 5 kg / cm 2 Up to 50kg / cm 2 This pressure can be adjusted based on the physical properties of the coated steel plate 10, such as its thickness and stiffness, or the number of pressure-applying parts 130 and 230. For example, the applied pressure can also be increased when the number of pressure-applying parts 130 and 230 provided on the device 10, or when the thickness or stiffness of the coated steel plate 10 is increased.

[0137] On the other hand, the clad steel sheet manufacturing apparatus 20 may further include a control unit (not shown). The control unit can control the operation of the clad steel sheet manufacturing apparatus 20. In this case, for example, the control unit may be implemented in the form of a circuit board installed on the control computer of the clad steel sheet manufacturing apparatus 20, a computer chip installed on the circuit board, software built into the computer chip, or software built into the control computer.

[0138] The control unit controls the galvanized steel sheet manufacturing apparatus 20 as follows. First, the galvanized steel sheet 10, which is to be pressed in, can be supplied between the pressing units 100 and 200. At this time, the first pressing unit 100 and the second pressing unit 200 can be separated by a predetermined distance, so that the galvanized steel sheet 10 can be moved between them. Alternatively, the supply of the galvanized steel sheet 10 can be performed by a separate transfer device (not shown) such as a conveyor.

[0139] Then, the control unit can determine (calculate) the pressing pressure based on the physical properties of the supplied coated steel sheet 10 (e.g., thickness, stiffness, etc.). At this time, the physical properties of the coated steel sheet 10 can be values ​​that the operator has input into the control unit in advance, or they can be obtained by measurement using a sensor (not shown) installed on the device 10.

[0140] Then, the control unit can raise and lower the pressing units 100 and 200 to bring them closer to each other. More specifically, the control unit can lower the first pressing unit 100 toward the plated steel sheet 10 and raise the second pressing unit 200 toward the plated steel sheet 10. At this time, in the case of Embodiment 1, the control unit can rotate the pressing units 100 and 200.

[0141] As described above, during rotational operation, the first pressure-applying part 130 can contact the upper plating layer 12a, and the second pressure-applying part 230 can contact the lower plating layer 12b. Then, as the pressure-applying parts 130 and 230 continue to rotate, pressure can be applied to the plating layers 12a and 12b. As a result, a pair of press-in parts 13 can be formed symmetrically in the vertical direction on the upper and lower surfaces of the plated steel sheet 10.

[0142] On the other hand, in the case of Embodiment 2, after the first pressing part 130 contacts the upper plating layer 12a and the second pressing part 230 contacts the lower plating layer 12b, the control unit can further lower the first pressing unit 100 and further raise the second pressing unit 200. Thus, by applying pressure to the plated steel sheet 10 in the vertical direction using the pressure determined (calculated) as described above, a pair of pressing parts 13 can be formed.

[0143] Then, after forming the pressing portion 13 at a predetermined depth P1, the control unit can raise and lower the pressing units 100 and 200 to move them away from each other. The pressed-processed coated steel sheet 10 can then be transferred to the cutting device via a transfer device. The control unit can control the cutting device to cut the coated steel sheet 10 along the virtual center line C of the pair of pressing portions 13.

[0144] However, the present invention is not limited thereto, and the galvanized steel sheet manufacturing apparatus 20 may also be without a control unit. In this case, the galvanized steel sheet manufacturing apparatus 20 can be operated by the operator to press the galvanized steel sheet 10, and then the operator can use a cutting device to cut the galvanized steel sheet 10.

[0145] Refer again Figure 2 The coated steel sheet 10, which is press-fitted by the coated steel sheet manufacturing apparatus 20, 20A according to Embodiment 1 or Embodiment 2 of the present invention, can have press-fit portions 13 formed at the upper and lower ends of the coated steel sheet 10, 10A, respectively. At this time, as described above, the upper / lower press-fit portions 13 can be the same or similar in shape and size to each other.

[0146] The width L1 of the press-in portion 13 can be a dimension corresponding to the width L2 of the pressure portions 130 and 230. Therefore, the width of the press-in portion 13 can be smaller than the width of the connecting portions 120 and 220. For example, when the width L2 of the pressure portions 130 and 230 is 0.5 mm to 8 mm, the press-in portion 13 formed using the pressure portions 130 and 230 can also have a width L1 in the range of 0.5 mm to 8 mm.

[0147] The protrusion distance P2 of the pressure-applying portions 130 and 230 can be greater than the thickness T2 of the coatings 12a and 12b, but less than the total thickness T1 of the coated steel sheets 10 and 10A. Since a pair of pressing portions 13 are formed by these pressure-applying portions 130 and 230, the thickness T3 of the pressed-in coated steel sheets 10 and 10A can be processed to, for example, 10% to 90% of the thickness T1 before pressing.

[0148] Figure 12 The diagram schematically illustrates the appearance of a galvanized steel sheet manufacturing apparatus according to another embodiment of the present invention before pressing a galvanized steel sheet into place. Furthermore, Figure 13 schematically shown Figure 11 The pattern of a steel plate processing device pressing a galvanized steel plate.

[0149] Reference Figure 12 and Figure 13 According to another embodiment of the present invention (hereinafter, Embodiment 3), the galvanized steel sheet manufacturing apparatus 20B may include a compression unit 100 and a support 300.

[0150] The support portion 300 can be installed at the bottom or on the inner wall of the building where the clad steel sheet manufacturing apparatus 20B is installed. The support portion 300 can be fixedly installed at the aforementioned location. The support portion 300 can be a flat planar shape, such that its upper surface is parallel to the longitudinal direction of the clad steel sheet 10B or the longitudinal direction of the main body 110. The clad steel sheet 10B can be supported on the upper surface of this support portion 300.

[0151] The compression unit 100 can be positioned facing the support portion 300, with the plated steel sheet 10B in between. In this case, the compression unit 100 can be raised or lowered to move closer to or further away from the upper surface of the plated steel sheet 10B. As an example, during press-fitting, the compression unit 100 can be lowered to apply pressure to the upper plating layer 12a of the plated steel sheet 10B supported on the support portion 300. As another example, the main body 100 can be rotatably configured so that the plated steel sheet 10B supported on the support portion 300 can be press-fitted via the pressing portion 130, which rotates together with the main body 100.

[0152] By performing the pressing process as described above, the pressing portion 13 can be formed only at the upper end of the plated steel sheet 10B. Other specific features of the compression unit 100 and the pressure portion 130 provided in the pressing unit 100 are the same as or in detail described above, so repeated descriptions will be omitted.

[0153] Refer again Figure 5bThe galvanized steel sheet 10B, which undergoes pressing processing using the galvanized steel sheet manufacturing apparatus 20B according to Embodiment 3 of the present invention, can have a pressing portion 13 formed only at its upper end. In this case, the width L1 of the pressing portion 13 can be a dimension corresponding to the width L2 of the pressing portions 130 and 230. Furthermore, similar to the galvanized steel sheet 10 according to Embodiment 1, the protrusion distance P2 of the pressing portion 110 is greater than the thickness T2 of the coatings 12a and 12b, and less than the total thickness T1 of the galvanized steel sheet 10B.

[0154] On the other hand, the width L1 and depth P1 of the press-in portion 13 can vary based on the pressure applied to the clad steel sheet 10B. More specifically, as the applied pressure increases, the width L2 and depth P2 of the press-in portion 13 formed on the clad steel sheet 10B can both increase proportionally. Conversely, the distance between a pair of facing press-in portions 13, i.e., the thickness T3 of the press-processed clad steel sheet 10B, can decrease inversely proportionally as the applied pressure increases.

[0155] The galvanized steel sheet manufacturing apparatuses 20, 20A, and 20B may include a cutting device (not shown). The cutting device can adjust the length of the cut-target portion CP of the galvanized steel sheets 10, 10A, and 10B by cutting it. As an example, the cutting device can perform the cutting process by cutting the cut-target portion CP along the cutting direction using a cutting tool (not shown). As described above, the cutting direction can be a direction parallel to the second direction B2 or the vertical direction Z. Through this cutting process, the galvanized steel sheets 10, 10A, and 10B can be divided into at least two parts.

[0156] In the above-described manner, after the pressing-in process of the galvanized steel sheets 10, 10A, and 10B is completed by the galvanized steel sheet manufacturing apparatuses 20, 20A, and 20B, the cutting device (not shown) can cut the pressing-in portion 13 in the vertical direction. At this time, in order to minimize the area of ​​the steel sheet 11 exposed to the outside, the cutting can be performed at the position where the thickness of the pressing-in portion 13 is the smallest (for example, the center portion C of the pressing-in portion 13). The cut galvanized steel sheets 10, 10A, and 10B can be used for various manufacturing processes.

[0157] Refer again Figures 6 to 11 The method for manufacturing coated steel sheets 10, 10A, and 10B according to embodiments of the present invention using coated steel sheet manufacturing apparatuses 20, 20A, and 20B is as follows. Hereinafter, for ease of explanation, the description will focus on the coated steel sheet manufacturing apparatus 20 and the coated steel sheet 10 according to Embodiment 1.

[0158] First, the galvanized steel sheet 10 can be supplied to the galvanized steel sheet manufacturing apparatus 20. At this time, the supplied galvanized steel sheet 10 can be flat on both its upper and lower surfaces and have the same or similar thickness T1 overall. That is, the galvanized steel sheet 10 before processing begins can be in a form comprising only the first galvanized steel sheet region A10. This galvanized steel sheet 10 can be in a wound state before being supplied to the manufacturing apparatus 20. After the manufacturing process begins, one end of the wound galvanized steel sheet 10 can be unwound and supplied between the pressing units 100 and 200.

[0159] Then, a pressing process can be performed to form a pressing portion 13 on the clad steel sheet 10. At this time, the pressing portions 130 and 230, driven by the rotation of the main bodies 110 and 210, can apply pressure to the upper and lower surfaces of the clad steel sheet 10. The clad steel sheet 10 can be supplied after the pressing units 100 and 200 start rotating, or simultaneously with the start of rotation.

[0160] More specifically, the galvanized steel sheet 10 passes between the rotating pressing sections 130 and 230, thereby forming a first pressing section 13a at the upper end of the galvanized steel sheet 10 and a second pressing section 13b at the lower end of the galvanized steel sheet 10. At this time, the first pressing section 13a and the second pressing section 13b can be formed facing each other along the second direction B2. Through this pressing process, a first galvanized steel sheet region A10 and a second galvanized steel sheet region A20 that are continuous with each other along the width direction (first direction) B1 can be formed on the galvanized steel sheet 10. At this time, the second galvanized steel sheet region A20 may be in a state where the cut section 14 is not formed.

[0161] On the other hand, in the pressing process, the pressure (pressing pressure) applied to the coated steel sheet 10 by the pressing units 100 and 200 can be adjusted according to the shape of the coated steel sheet 10 to be manufactured. For example, the pressing pressure can be 5 kg / cm². 2 Up to 300kg / cm 2 The adjustment is possible within a certain range, but not limited to this. Based on this pressing pressure, the width L1 and pressing depth P1 of the pressing portion 13 can be changed. For example, when the pressure applied to the coated steel sheet 10 increases or decreases, the width L1 of the pressing portion 13 (or the width of the second coated steel sheet area) and the pressing depth P1 can be increased or decreased proportionally.

[0162] Furthermore, since the thickness T3 of the cut portion 14 formed by the cutting process described later is determined based on the thickness of the second plated steel plate region A20, the thickness T3 of the cut portion 14 can also vary based on the pressing pressure. For example, if the applied pressing pressure increases or decreases, the thickness T3 of the cut portion 14 can decrease or increase inversely. Therefore, the area of ​​the second steel plate region A21 exposed to the outside through the cut portion 14 can be determined.

[0163] Then, after the pressing process is completed, a cutting process can be performed to form a cut portion 14 on the plated steel sheet 10. During the cutting process, a cutting tool (not shown) can be used to simultaneously cut the first pressing portion 13a and the second pressing portion 13b, which are positioned facing each other. At this time, the cutting tool can cut the second plated steel sheet region A20 along a direction passing through the common center C of the pressing portions 13a and 13b and parallel to the thickness direction (second direction) B2 of the plated steel sheet 10. Thus, the cut portion 14 can be formed at the second end point E2 of the second plated steel sheet region A20.

[0164] On the other hand, during the cutting process, since the second plating area A20 is cut by the cutting tool, a portion of the plating material contained in the second plating area A20 moves onto the cutting portion 14, thereby forming a third plating area A30. This third plating area A30 has a shape that extends along the second direction B2, thereby covering at least a portion of the cutting portion 14.

[0165] Alternatively, even though there is no plating material on the cut portion 14 at the time of initial cutting, a portion of the plating material in the second plating region A20 may move onto the cut portion 14 due to sacrificing corrosion protection, thus forming a third plating region A30.

[0166] Then, the galvanized steel sheet 10 that has completed the cutting process can be transported according to its intended use for subsequent processes or manufacturing operations.

[0167] As described above, in the galvanized steel sheets 10, 10A, and 10B according to embodiments of the present invention, after pressing the material into the cut area to reduce its thickness, the pressed portion is then cut, thereby minimizing the area of ​​the steel sheet 11 exposed to the outside due to the cutting process. Thus, by delaying the rusting time at the cut portion, the galvanized steel sheets 10, 10A, and 10B can maintain improved corrosion resistance even after cutting.

[0168] Furthermore, during the pressing process, since the inwardly curved pressing portions 13 are formed on the coated steel sheets 10, 10A, and 10B, damage such as damage or peeling of the coating 12 can be prevented during the pressing process compared to existing pressing processes using sharp-shaped structures. Moreover, during the pressing process, pressure is applied using the curved pressure portions 130 and 230 corresponding to the pressing portions 13, preventing a sharp reduction in thickness and coating amount in the pressing portions 13, thereby further improving the corrosion resistance of the coated steel sheets 10, 10A, and 10B.

[0169] Figure 14a The image shows a plated steel sheet before it is cut. Figure 14b This shows a plated steel sheet with a cut section formed by cutting. Figure 15 The diagram schematically illustrates the state of the coated steel sheet according to the present invention after cutting and before pressing. Additionally, Figure 16 It is an enlarged cross-sectional view showing a portion of a galvanized steel sheet manufactured after cutting and pressing processes.

[0170] Reference Figures 14a to 16 According to another embodiment of the present invention, a method for manufacturing coated steel sheets 10, 10A, and 10B (hereinafter, the coated steel sheet manufacturing method) can be performed as follows. This coated steel sheet manufacturing method can be performed using coated steel sheet manufacturing apparatus 20, 20A, and 20B. Hereinafter, for ease of explanation, the description will focus on the coated steel sheet manufacturing apparatus 20 and the coated steel sheet 10 according to Embodiment 1.

[0171] First, the galvanized steel sheet 10 can be supplied to the galvanized steel sheet manufacturing apparatus 20. The specific method for supplying the galvanized steel sheet 10 is the same as or similar to the method described above, so a repetition will be omitted.

[0172] Then, a cutting process can be performed by a cutting device to form a cut portion 14 on the galvanized steel sheet 10. In the cutting process, a cutting tool (not shown) can be used to cut a portion (i.e., the cutting target portion) CP of the galvanized steel sheet 10. At this time, the cutting tool can cut the cutting target portion CP in a direction parallel to the thickness direction (second direction) B2 of the galvanized steel sheet 10.

[0173] Therefore, by forming the cutting section 14, multiple coated steel sheets 10 with adjustable (reduced) lengths can be manufactured. In the cutting process, at least one cutting target section CP of the coated steel sheet 10 is cut by a cutting device, thereby forming at least two cutting sections 14. For example, the cutting section 14 can be formed as two or more.

[0174] On the other hand, during the cutting process, since the plated steel sheet 10 is cut by a cutting tool, a portion of the plating material contained in the second plating region A20 can be moved onto the cutting section 14. As a result, a third plating region A30 can also be formed on the plated steel sheet 10. This third plating region A30 has a shape extending along the second direction B2, thereby covering at least a portion of the cutting section 14.

[0175] Alternatively, even though there is no plating material on the cut portion 14 at the time of initial cutting, a portion of the plating material in the second plating region A20 may move onto the cut portion 14 due to sacrificing corrosion protection, thus forming a third plating region A30.

[0176] Then, a pressing process can be performed to form a pressing portion 13 on the galvanized steel sheet 10. After the cutting process, the galvanized steel sheet 10 with the cutting portion 14 formed can pass between the rotating pressing portions 130 and 230. In this process, the pressing portions 130 and 230, driven by the rotation of the main bodies 110 and 210, can apply pressure to the upper and lower surfaces of the galvanized steel sheet 10. The pressing portions 130 and 230 can also apply pressure to the pressing target portion PP of the galvanized steel sheet 10.

[0177] The pressing-in portion PP is part of the upper and lower surfaces of the clad steel sheet 10, and may include the area containing the cutting portion 14. More specifically, two pressing-in portions PP may be arranged as a set, with one on each of the upper and lower surfaces of the clad steel sheet 10. The two pressing-in portions PP may be arranged opposite each other along the thickness direction (second direction) B2 of the clad steel sheet 10. In this case, the cutting portion 14 may be located at the common center C of the two pressing-in portions PP.

[0178] As described above, the two pressing-in target portions PP are pressed in by the pressing portions 130 and 230, thereby forming the pressing portion 13 on the galvanized steel sheet 10. More specifically, an upper pressing portion 13A can be formed at the upper end of the galvanized steel sheet 10, and a lower pressing portion 13B can be formed at the lower end of the galvanized steel sheet 10. Since the upper pressing portion 13A and the lower pressing portion 13B are formed on the pressing target portion PP, they can be formed facing each other along the second direction B2. At this time, the upper pressing portion 13A and the lower pressing portion 13B facing each other can be in a state of being cut by the cutting portion 14 passing through their center C. That is, the upper pressing portion 13A can include two first pressing portions 13a in a state of being cut from each other, and the lower pressing portion 13B can include two second pressing portions 13b in a state of being cut from each other.

[0179] Furthermore, multiple sets of press-in target portions PP can be provided corresponding to the number of cutting portions 14. These multiple sets of press-in target portions PP can be spaced apart at predetermined intervals along the length direction B1 of the coated steel sheet 10. Here, the predetermined interval can correspond to the interval between the multiple cutting portions 14. In this case, the multiple sets of press-in target portions PP can be pressed in simultaneously by the rotating pressing portions 130, 230. Therefore, multiple upper press-in portions 13A can be formed on the upper surface of the coated steel sheet 10, and multiple lower press-in portions 13B can be formed on the lower surface of the coated steel sheet 10, facing each other one-to-one with the upper press-in portions 13A. As described above, these multiple upper press-in portions 13A and multiple lower press-in portions 13B are respectively cut by the cutting portions 14.

[0180] Through this pressing process, a first coated steel plate region A10 and a second coated steel plate region A20 can be continuously formed on the coated steel plate 10 along the width direction (first direction) B1. On the other hand, in the pressing process, the coated steel plate 10 with the cutting portion 140 can be supplied to the pressing units 100 and 200 after they start rotating, or at the same time as the pressing units 100 and 200 start rotating.

[0181] Furthermore, during the pressing process, the pressure (pressing pressure) applied to the coated steel sheet 10 by the pressing units 100 and 200 can be adjusted according to the shape of the coated steel sheet 10 to be manufactured. For example, the pressing pressure can be 5 kg / cm². 2 Up to 300kg / cm 2 The adjustment is possible within a certain range, but not limited to this. Based on this pressing pressure, the width L1 and pressing depth P1 of the pressing portion 13 can be changed. For example, when the pressure applied to the coated steel sheet 10 increases or decreases, the width L1 of the pressing portion 13 (or the width of the second coated steel sheet area) and the pressing depth P1 can be increased or decreased proportionally.

[0182] Furthermore, since the thickness T3 of the cut portion 14 is determined based on the thickness of the second plated steel plate region A20, the thickness T3 of the cut portion 14 can also vary based on the pressing pressure. For example, if the applied pressing pressure increases or decreases, the thickness T3 of the cut portion 14 can decrease or increase inversely. Therefore, the area of ​​the second steel plate region A21 exposed to the outside through the cut portion 14 can be determined.

[0183] The galvanized steel sheet 10 can be manufactured by sequentially performing the cutting and pressing steps described above. The galvanized steel sheet 10 includes a first galvanized steel sheet region A10 and a second galvanized steel sheet region A20 having a pressing part 13 and a cutting part 14. As described above, the manufactured galvanized steel sheet 10 can be transported according to its intended use for subsequent processes or manufacturing operations.

[0184] As described above, the galvanized steel sheets 10, 10A, and 10B according to embodiments of the present invention are manufactured by reducing their thickness by cutting the cutting target portion CP at the cutting target location, and then pressing the pressing target portion PP including the cutting target portion CP. This minimizes the area of ​​the steel sheet 11 exposed to the outside due to the cutting process. Consequently, by delaying the rusting time at the cut portion, the galvanized steel sheets 10, 10A, and 10B can maintain improved corrosion resistance even after cutting.

[0185] Furthermore, during the pressing process, since the inwardly curved pressing portions 13 are formed on the coated steel sheets 10, 10A, and 10B, damage such as damage or peeling of the coating 12 can be prevented during the pressing process compared to existing pressing processes using sharp-shaped structures. Moreover, during the pressing process, pressure is applied using the curved pressure portions 130 and 230 corresponding to the pressing portions 13, preventing a sharp reduction in thickness and coating amount in the pressing portions 13, thereby further improving the corrosion resistance of the coated steel sheets 10, 10A, and 10B.

[0186] As described above, in the embodiments of the present invention, the coated steel sheets 10, 10A, and 10B are press-fitted at the cutting location before or after cutting to reduce the thickness. Therefore, even after cutting, the area of ​​the steel sheet 11 exposed to the outside can be minimized. Consequently, by delaying the rusting time at the cut portion, the coated steel sheets 10, 10A, and 10B can maintain improved corrosion resistance even after cutting.

[0187] Furthermore, during the pressing process, since the inwardly curved pressing portions 13 are formed on the coated steel sheets 10, 10A, and 10B, damage such as damage or peeling of the coating 12 can be prevented during the pressing process compared to existing pressing processes using sharp-shaped structures. Moreover, during the pressing process, pressure is applied using the curved pressure portions 130 and 230 corresponding to the pressing portions 13, preventing a sharp reduction in thickness and coating amount in the pressing portions 13, thereby further improving the corrosion resistance of the coated steel sheets 10, 10A, and 10B.

[0188] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical concept or essential features. Therefore, the above embodiments should be understood as exemplary in all respects and not limiting.

[0189] Industrial applicability This invention can be applied to industrially practical coated steel sheets, coated steel sheet manufacturing equipment, and manufacturing methods.

Claims

1. A galvanized steel sheet, comprising: The first clad steel plate area extends along a first direction and includes the first steel plate area and the first clad area; as well as The second coated steel plate area extends along the first direction and includes the second steel plate area and the second coated area. The second galvanized steel plate area includes: The first end is continuous with the first plated steel plate area; The second end is formed in the opposite direction to the first end; The pressed-in portion is formed by pressing inward along a second direction on the upper or lower surface of the second plating area, and has a pressing depth; and A cutting section is provided at the second end of the second coated steel plate area and extends along the second direction. The width of the second coated steel plate area is greater than the pressing depth.

2. The galvanized steel sheet according to claim 1, wherein, The pressing depth of the pressing part changes along the first direction.

3. The galvanized steel sheet according to claim 2, wherein, The pressing depth of the pressing portion gradually increases from the first end of the second coated steel plate region toward the second end along the first direction.

4. The galvanized steel sheet according to claim 1, wherein, The pressed portion has a shape that bends inward toward the area of ​​the second plated steel sheet.

5. The plated steel sheet according to claim 4, wherein, Between the first end and the second end of the second coated steel plate region, the slope of the tangent of the press-in portion changes along the first direction.

6. The plated steel sheet according to claim 5, wherein, Between the center of the second end and the second end of the second galvanized steel plate region, the average slope of the tangent is less than or equal to 45°.

7. The coated steel sheet according to claim 4, wherein, The pressed portion has a minimum radius of curvature at the second end of the second coated steel plate region and a maximum radius of curvature at the first end of the second coated steel plate region.

8. The galvanized steel sheet according to claim 7, wherein, The minimum radius of curvature is 0.25 mm.

9. The galvanized steel sheet according to claim 1, wherein, The thickness of the second coated steel plate area is 10% to 90% of the thickness of the first coated steel plate area.

10. The galvanized steel sheet according to claim 1, wherein, The second plating area has a first thickness at the first end of the second plating steel plate area and a second thickness at the second end of the second plating steel plate area that is less than or equal to the first thickness.

11. The galvanized steel sheet according to claim 1, further comprising: The third plating area extends along the second direction to cover at least a portion of the cut portion.

12. The galvanized steel sheet according to claim 11, wherein, The thickness of the third plating area is less than the thickness of the second plating area.

13. The galvanized steel sheet according to claim 11, wherein, The amount of plating in the third plating area is less than the amount of plating in the second plating area.

14. The galvanized steel sheet according to claim 1, wherein, The density of the second plating area is greater than the density of the first plating area.

15. The plated steel sheet according to claim 1, wherein, The density of the second steel plate region is greater than the density of the first steel plate region.

16. The galvanized steel sheet according to claim 1, wherein, The width of the press-in portion is 0.25 mm to 4 mm.

17. The galvanized steel sheet according to claim 1, wherein, The second galvanized steel plate area includes: The first pressing portion is recessed downward from the upper surface of the second plating area; and The second pressing part is disposed facing the first pressing part and is recessed upward from the lower surface of the second plating area.

18. A method for manufacturing galvanized steel sheet, comprising the following steps: The supply includes a coated steel sheet comprising a first coated steel sheet region, wherein the first coated steel sheet region includes a first coated area and a first steel sheet region; The galvanized steel sheet is pressed into shape to form a second galvanized steel sheet region, the second galvanized steel sheet region extending along a first direction and including a second galvanized region and a second steel sheet region; as well as A cut portion extending in a second direction is formed in the second coated steel plate area.

19. The method for manufacturing coated steel sheet according to claim 18, wherein, In the step of forming the second coated steel plate area A pressing portion is formed, which is recessed into the inner side of the second plating area along the second direction, and the width is greater than the pressing depth.

20. The method for manufacturing coated steel sheet according to claim 19, wherein, The pressing pressure applied to the second plating area is 5 kg / cm. 2 Up to 300kg / cm 2 .

21. The method for manufacturing coated steel sheet according to claim 20, wherein, In the step of forming the cut portion The cutting portion is formed at the center of the pressing portion.

22. The method for manufacturing coated steel sheet according to claim 20, wherein, In the step of forming the cut portion A third plating area is further formed, which extends along the second direction and covers at least a portion of the cut portion.

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