Patent Application
20240149394
The present disclosure relates to a method for producing a textured plated steel sheet, and an apparatus for producing a textured plated steel sheet.
Products such as electrical machinery and apparatuses, building materials, and automobiles are sometimes required to have corrosion resistance and a design property. Textured plated steel sheets are being studied as a material suitable for such applications. A textured plated steel sheet includes, on the surface thereof, a plating layer on the surface of which a texture typified by a hairline texture is formed.
Methods for producing a textured plated steel sheet are proposed, for example, in Japanese Patent Application Publication No. 2006-124824 (Patent Literature 1) and International Application Publication No. WO2008/054419 (Patent Literature 2).
Patent Literature 1 discloses forming a zinc plating layer on the surface of a steel sheet, and forming hairlines on the surface of the zinc plating layer by grinding the surface of the zinc plating layer using a belt sander (abrasive belt) ranging from about #60 to #320.
Patent Literature 2 proposes a method for polishing a metal alloy-plated steel sheet article. The polishing method disclosed in Patent Literature 2 is a method for polishing a metal alloy-plated steel sheet article to form a polished plated surface having a continuous and consistent stainless steel-like appearance, the method including: a) a step of providing a metal alloy-plated steel sheet article having a minimized spangle plating film; b) a step of embossing the minimized spangle plating film to form an intermediate metal alloy-plated steel sheet article having a plating film that is embossed with a textured pattern that provides the continuous and consistent stainless steel-like appearance when polished; and c) a step of polishing the plating film that is embossed with the textured pattern to produce the continuous and consistent stainless steel-like appearance.
In this connection, when a textured plated steel sheet is produced by grinding the surface of a plating layer, in some cases the thickness of the plating layer is insufficient, or the texture is not sufficiently formed and there is an appearance defect, and thus a product defect occurs. It is preferable that the cause of a product defect can be quickly identified. If the cause of a product defect can be quickly identified and the cause of the product defect eliminated, the occurrence of product defects can be suppressed.
However, in the methods for producing a textured plated steel sheet disclosed in the aforementioned Patent Literatures 1 and 2, no consideration is given to the occurrence of a product defect. Therefore, when producing textured plated steel sheets according to the methods disclosed in the aforementioned Patent Literatures 1 and 2, in some cases the occurrence of product defects cannot be suppressed.
An objective of the present disclosure is to provide a method for producing a textured plated steel sheet that can suppress the occurrence of product defects which are based on an insufficient thickness of a plating layer and an appearance defect, and also provide an apparatus for producing a textured plated steel sheet with which the cause of product defects which are based on an insufficient thickness of a plating layer and an appearance defect is easy to identify.
A method for producing a textured plated steel sheet according to the present disclosure includes:
An apparatus for producing a textured plated steel sheet according to the present disclosure includes:
The method for producing a textured plated steel sheet according to the present disclosure can suppress the occurrence of product defects which are based on an insufficient thickness of a plating layer and an appearance defect. The apparatus for producing a textured plated steel sheet according to the present disclosure easily identifies a cause of product defects which are based on an insufficient thickness of a plating layer and an appearance defect.
A method for producing a textured plated steel sheet, for example, includes a plating layer forming process, and a grinding process after the plating layer forming process. In the plating layer forming process, a plating layer is formed on a surface of a steel sheet to produce a plated steel sheet. The grinding process is performed after the plating layer forming process. In the grinding process, for example, the surface of the plating layer of the plated steel sheet is ground to form a texture on the surface of the plating layer.
Here, the texture is a pattern formed by unevenness on the surface of the plating layer. Examples of the texture include hairline texture and vibration texture. The hairline texture is a pattern formed by a large number of fine linear grooves. The vibration texture is a pattern formed by a large number of fine arcuate grooves.
After the plating layer of the textured plated steel sheet is formed on the surface of the steel sheet, the plating layer is ground. That is, on the textured plated steel sheet, a plating layer is arranged that has a final thickness which is the thickness of the plating layer after the plating layer is formed and ground.
The plating layer of the textured plated steel sheet increases the corrosion resistance of the textured plated steel sheet. If the final thickness of the plating layer is less than a certain value, that is, if there is an insufficient final thickness, the corrosion resistance of the textured plated steel sheet will decrease. Accordingly, when the final thickness of the plating layer is less than a certain value, it will result in a product defect.
On the other hand, in the grinding process, if the plating layer is sufficiently ground, the texture will be sufficiently formed. In this case, the design property of the textured plated steel sheet will be enhanced. The present inventors considered that when the plating layer is sufficiently ground, the final thickness of the plating layer becomes a certain value or less.
The present inventors considered that the final thickness of the plating layer can be used as an index that indicates the corrosion resistance and a design property of the textured plated steel sheet. The present inventors considered that if a reference range is provided for the final thickness of the plating layer, and the final thickness of the plating layer is within the reference range, it can be determined that the textured plated steel sheet has excellent corrosion resistance and an excellent design property.
Therefore, the present inventors set a reference range for the final thickness of the plating layer of a textured plated steel sheet. The present inventors considered that if the operating conditions are adjusted based on the final thickness of the plating layer, product defects which are based on an insufficient final thickness of the plating layer and an appearance defect can be suppressed.
However, in some cases product defects based on an insufficient final thickness of the plating layer and an appearance defect of a textured plated steel sheet could not be suppressed by only adjusting the operating conditions based on the final thickness of the plating layer. The present inventors investigated the reason for this. As a result, the present inventors obtained the following findings.
For example, a case will be assumed in which the final thickness of the plating layer is insufficient. In some cases the final thickness of the plating layer will be less than a reference range even if the plating amount of the plating layer that is formed in the plating layer forming process is increased in order to increase the final thickness of the plating layer. Such a case is one where the grinding amount of the plating layer that is ground in the grinding process is too much. On the other hand, in some cases if the grinding amount of the plating layer that is ground in the grinding process is decreased in order to increase the final thickness of the plating layer, the texture will not be sufficiently formed, which will result in an appearance defect. Such a case is one where the plating amount of the plating layer that is formed in the plating layer forming process is too small. In this case, it is necessary to increase the grinding amount of the plating layer that is ground in the grinding process, and at the same time to also increase the plating amount of the plating layer that is formed in the plating layer forming process.
For example, a case will be assumed in which a texture is not sufficiently formed, and an appearance defect occurs. In some cases, if the grinding amount of the plating layer that is ground in the grinding process is increased in order to sufficiently form a texture, the final thickness of the plating layer will be less than the reference range. Such a case is one where the plating amount of the plating layer that is formed in the plating layer forming process is too small. In this case, it is necessary to increase the grinding amount of the plating layer that is ground in the grinding process, and at the same time to also increase the plating amount of the plating layer that is formed in the plating layer forming process.
Based on the investigation described above, it was found that the final thickness of a plating layer cannot be used as an index that indicates the corrosion resistance and a design property of a textured plated steel sheet. From the investigation described above, it was found that the final thickness and appearance of a plating layer are influenced by the following two factors: (1) the plating amount of the plating layer formed in the plating layer forming process, and (2) the grinding amount of the plating layer that is ground in the grinding process. The present inventors found that by only measuring the final thickness of the plating layer, it is not possible to identify whether a product defect which is based on an insufficient final thickness of the plating layer and/or an appearance defect has occurred due to (1) and/or (2).
Therefore, the present inventors conducted studies regarding a method for solving this problem. Here, information relating to the thickness of a plating layer of a plated steel sheet at a time that is after the plating layer forming process and is before the grinding process is referred to as “first plating thickness information”. Information relating to the thickness of a plating layer of a plated steel sheet after the grinding process is referred to as “second plating thickness information”. The present inventors considered that if not just the second plating thickness information relating to the plating thickness after grinding, but also the first plating thickness information relating to the plating thickness before grinding can both be obtained, the cause of a product defect which is based on an insufficient final thickness of the plating layer and/or an appearance defect can be quickly identified. Further, the present inventors considered that if the operating conditions are adjusted based on both the first plating thickness information and the second plating thickness information, the occurrence of product defects which are based on a decrease in corrosion resistance due to an insufficient final thickness of a plating layer and also an appearance defect with respect to a textured plated steel sheet can be suppressed.
The present inventors also conducted studies regarding an apparatus for producing a textured plated steel sheet which easily identifies the cause of product defects which are based on an insufficient final thickness of a plating layer and an appearance defect. An apparatus for producing a textured plated steel sheet that is uses in the aforementioned method for producing a textured plated steel sheet includes, for example, a plating apparatus and a grinding apparatus. The plating apparatus forms a plating layer on a steel sheet surface to produce a plated steel sheet. The grinding apparatus is arranged downstream of the plating apparatus, and grinds the surface of the plating layer of the plated steel sheet to form a texture on the surface of the plating layer. The present inventors considered that it suffices that the apparatus for producing a textured plated steel sheet also includes a first plating thickness determining apparatus and a second plating thickness determining apparatus. The first plating thickness determining apparatus determines first plating thickness information relating to the thickness before grinding of the plating layer, and outputs the first plating thickness information. The second plating thickness determining apparatus is arranged downstream of the grinding apparatus, and determines second plating thickness information relating to the thickness of the plating layer that has been ground, and outputs the second plating thickness information. It is considered that if an apparatus for producing a textured plated steel sheet has the aforementioned configuration, it will be easy to identify whether the cause of a product defect that occurs is (1) the plating amount of the plating layer formed in the plating layer forming process, and/or (2) the grinding amount of the plating layer that is ground in the grinding process.
A method for producing a textured plated steel sheet of the present embodiment, which has been completed based on the above findings, is as follows.
[1]
A method for producing a textured plated steel sheet, including:
[2]
The method for producing a textured plated steel sheet according to [1], wherein,
[3]
The method for producing a textured plated steel sheet according to [2], wherein,
[4]
The method for producing a textured plated steel sheet according to any one of [1] to [3], wherein,
[5]
The method for producing a textured plated steel sheet according to any one of [1] to [4], wherein,
[6]
The method for producing a textured plated steel sheet according to any one of [1] to [5], wherein:
[7]
The method for producing a textured plated steel sheet according to any one of [1] to [5], wherein:
[8]
The method for producing a textured plated steel sheet according to any one of [1] to [7], further including:
[9]
The method for producing a textured plated steel sheet according to any one of [1] to [8], further including:
[10]
The method for producing a textured plated steel sheet according to [9], wherein:
[11]
The method for producing a textured plated steel sheet according to [9] or [10], wherein:
[12]
An apparatus for producing a textured plated steel sheet, including:
[13]
The apparatus for producing a textured plated steel sheet according to [12], further including:
[14]
The apparatus for producing a textured plated steel sheet according to [13], wherein the control unit:
[15]
The apparatus for producing a textured plated steel sheet according to [14], wherein the control unit:
[16]
The apparatus for producing a textured plated steel sheet according to any one of [12] to [15], further including:
[17]
The apparatus for producing a textured plated steel sheet according to any one of [12] to [16], further including:
[18]
The apparatus for producing a textured plated steel sheet according to [17], wherein:
[19]
The apparatus for producing a textured plated steel sheet according to [17] or [18], wherein the control unit:
Hereunder, the method for producing a textured plated steel sheet and the apparatus for producing a textured plated steel sheet of the present embodiment are described. The same reference numerals are assigned to the same or corresponding portions in the drawings, and the description of the portions is not repeated.
[Regarding Apparatus for Producing a Textured Plated Steel Sheet]
A straight line in
[Regarding Plating Apparatus]
The plating apparatus 2 performs hot-dip plating or electroplating to form a plating layer on the surface of a steel sheet to produce a plated steel sheet. The hot-dip plating is selected, for example, from the group consisting of hot-dip galvanizing and hot-dip aluminum plating. The electroplating is selected, for example, from the group consisting of electrogalvanizing, copper electroplating, and nickel electroplating. The plating apparatus 2 is not particularly limited as long as the plating apparatus 2 performs hot-dip plating or electroplating. Preferably, the plating apparatus 2 is a hot-dip galvanizing apparatus that performs hot-dip galvanizing, or is an electrogalvanizing apparatus that performs electrogalvanizing. Hereunder, a case where an electrogalvanizing apparatus is used and a case where a hot-dip galvanizing apparatus is used are described as examples.
[Electrogalvanizing Apparatus]
The electrogalvanizing apparatus 200 in
[Hot-Dip Galvanizing Apparatus]
The gas wiping apparatus 214 is arranged at a position that is above the liquid surface of the hot-dip galvanizing bath. The gas wiping apparatus 214 includes a pair of gas spraying apparatuses. The pair of gas spraying apparatuses have gas spraying nozzles which face each other. The steel sheet 6 passes between the pair of gas spraying nozzles of the gas wiping apparatus 214. The pair of gas spraying nozzles spray a wiping gas against the surface of the steel sheet 6 which is pulled up from the hot-dip galvanizing bath. By this means, some of the molten zinc that adhered to the surface of the steel sheet 6 is scraped off. The steel sheet 7 from which a part of the molten zinc on the surface was scraped off is conveyed to the skin pass mill 218 by the top roll 216 and the transfer rolls 217.
In the hot-dip galvanizing apparatus 210 illustrated in
[Regarding Grinding Apparatus]
The grinding apparatus 3 is arranged downstream of the plating apparatus 2, and grinds the surface of a plating layer of the plated steel sheet 7 to form a texture on the surface of the plating layer. Examples of the texture include a hairline texture and a vibration texture.
As one example, a case of forming a hairline texture will be described.
The grinding apparatus 3 in
[Regarding First Plating Thickness Determining Apparatus]
The first plating thickness determining apparatus 4 determines first plating thickness information relating to the thickness before grinding of the plating layer, and outputs the first plating thickness information. The first plating thickness determining apparatus 4 includes a screen, and the first plating thickness information may be output onto the screen.
The first plating thickness information is information relating to the thickness before grinding of the plating layer. The first plating thickness information, for example, may be a thickness (μm) of the plating layer before grinding, may be a plating amount (g/m2) of the plating layer before grinding, or may be plating conditions in the plating apparatus 2. The plating conditions in the plating apparatus 2 are, for example, a metal ion concentration in the plating solution, a line speed of the steel sheet into the plating solution, a width direction length of the steel sheet, a temperature and/or pH of the plating solution and the like. In a case where the plating apparatus 2 is the plating apparatus 2 that performs electroplating, the plating conditions may be a metal ion concentration in the plating solution, the line speed of the steel sheet into the plating solution, the width direction length of the steel sheet, the current density, the current efficiency, and/or the temperature of the plating solution. In a case where the plating apparatus 2 is the plating apparatus 2 that performs hot-dip plating, the plating conditions may be the line speed of the steel sheet into the plating solution, an impact pressure of a wiping gas, and/or a rolling reduction at the skin pass mill 218. That is, the term “first plating thickness information” includes the plating thickness before grinding and all information that can be used to estimate the plating thickness before grinding.
The first plating thickness determining apparatus 4 determines the first plating thickness information relating to the thickness before grinding of the plating layer. The first plating thickness information may be determined by measurement. Specifically, the thickness (μm) of the plating layer at a time that is after the plating layer is formed by the plating apparatus 2 and is before grinding of the plating layer is performed by the grinding apparatus 3 may be measured, or the plating amount (g/m2) of the plating layer before grinding may be measured, and the measured thickness (μm) or plating amount (g/m2) may be determined as the first plating thickness information. In this case, the first plating thickness determining apparatus 4 is, for example, a fluorescent X-ray film thickness meter. The first plating thickness information may be a plating condition at the plating apparatus 2. In the case of determining a plating condition as the first plating thickness information, the first plating thickness determining apparatus 4 may measure the plating condition. In this case, the first plating thickness determining apparatus 4 is, for example, a voltmeter, an ammeter, an ion meter, a thermometer, or a gas pressure meter.
The thickness (μm) of the plating layer before grinding or the plating amount (g/m2) of the plating layer before grinding may be calculated based on a plating condition at the plating apparatus 2, and determined as the first plating thickness information. The first plating thickness determining apparatus 4 measures the plating condition, and calculates the thickness (μm) of the plating layer before grinding or the plating amount (g/m2) of the plating layer before grinding based on the measured plating conditions, and outputs the calculation result. For example, the first plating thickness determining apparatus 4 may include a memory that stores a plating thickness determination table. In this case, the first plating thickness determining apparatus 4 may, for example, in the plating thickness determination table, identify a thickness (μm) of the plating layer before grinding or a plating amount (g/m2) of the plating layer before grinding that corresponds to a line speed of a steel sheet, a width direction length of a steel sheet, and a measured plating condition which were input in advance, and determine the identified thickness (μm) or plating amount (g/m2) as the first plating thickness information. For example, the first plating thickness determining apparatus 4 may calculate the thickness (μm) of the plating layer before grinding or the plating amount (g/m2) of the plating layer before grinding using, for example, a pre-stored calculation program based on a line speed of a steel sheet, a width direction length of a steel sheet, and a measured plating condition which were input in advance, and determine the calculated thickness (μm) or plating amount (g/m2) as the first plating thickness information.
[Regarding Second Plating Thickness Determining Apparatus]
The second plating thickness determining apparatus 5 is arranged downstream of the grinding apparatus 3, and determines second plating thickness information relating to the thickness of the plating layer that has been ground, and outputs the second plating thickness information. The second plating thickness determining apparatus 5 includes a screen, and the second plating thickness information may be output onto the screen.
The second plating thickness information, for example, may be a thickness (μm) of the plating layer after grinding, or may be a plating amount (g/m2) of the plating layer after grinding. The second plating thickness information is determined by measurement. Specifically, the thickness (μm) of the plating layer after grinding of the plating layer is performed by the grinding apparatus 3 may be measured, or the plating amount (g/m2) of the plating layer after grinding may be measured, and the measured thickness (μm) or plating amount (g/m2) may be determined as the second plating thickness information. In this case, the second plating thickness determining apparatus 5 is, for example, a fluorescent X-ray film thickness meter.
The aforementioned apparatus for producing a textured plated steel sheet 1 includes not only the second plating thickness determining apparatus 5, but also includes the first plating thickness determining apparatus 4. Therefore, in a case where product defects which are based on an insufficient thickness of a plating layer and an appearance defect occur, from among two factors which are (1) the plating amount of the plating layer formed in the plating layer forming process and (2) the grinding amount of the plating layer that has been ground in the grinding process, it is easy to identify which of the factors caused the product defect to occur.
[Method for Producing Textured Plated Steel Sheet]
A method for producing a textured plated steel sheet using the aforementioned apparatus for producing a textured plated steel sheet 1 will now be described. The method for producing a textured plated steel sheet of the present embodiment includes a plating layer forming process, a grinding process, a plating thickness determining process, and an adjusting process.
[Plating Layer Forming Process]
In the plating layer forming process, a plating layer is formed on the surface of the steel sheet 6 by an electroplating method or a hot-dip plating method to produce the plated steel sheet 7. In the case of producing the aforementioned textured plated steel sheet by an electroplating method, the plating apparatus 2 is, for example, the electrogalvanizing apparatus 200. In the case of producing the aforementioned textured plated steel sheet by a hot-dip plating method, the plating apparatus 2 is, for example, the hot-dip galvanizing apparatus 210.
[Electrogalvanizing Process]
As one example, a case in which a plating layer is formed on the surface of the steel sheet 6 by an electrogalvanizing process to produce the plated steel sheet 7 will be described. The electrogalvanizing process may be performed by a well-known method. In the present description, the term “electrogalvanizing process” also includes a zinc alloy electroplating process. It suffices to use a well-known plating solution as the plating solution used in the electrogalvanizing process. The electrogalvanizing solution is, for example, a sulfate bath, a chloride bath, a zincate bath, a cyanide bath, a pyrophosphate bath, a boric acid bath, a citrate bath, another complex bath, or a combination of these baths. The zinc alloy electroplating solution contains, for example, in addition to Zn ions, one or more kinds of single ions or complex ions selected from the group consisting of Fe, Ni, Co, Cr and C. Further, an appropriate organic addition agent or the like may be added to the plating solution in order to obtain a desired effect such as a leveling effect or an increase in hardness.
For example, a plating solution containing zinc sulfate heptahydrate: 200 to 400 g/L, and sodium sulfate: 15 to 100 g/L, and having a pH of 1.0 to 2.5 can be used as the plating solution that is used in the electrogalvanizing process.
In the electrogalvanizing process, a zinc ion concentration, a temperature, a pH, a line speed of the steel sheet 6, a current density and the like in the electrogalvanizing solution and the zinc alloy electroplating solution can be appropriately set. The zinc ion concentration in the plating solution is, for example, 0.8 to 1.5 mol/L. The temperature of the plating solution is, for example, 40 to 60° C. The line speed of the steel sheet 6 is, for example, 20 to 200 m/min. The current density is, for example, 10 to 200 A/dm2. The thickness of the plating layer formed by performing the electrogalvanizing process can be adjusted, for example, by adjusting the line speed of the steel sheet 6 into the plating solution and/or the current density when performing the electrogalvanizing process. By this means, a plating layer is formed on the surface of the steel sheet 6, and the plated steel sheet 7 can be produced.
[Hot-Dip Galvanizing Process]
As one example, a case where a plating layer is formed on the surface of the steel sheet 6 by a hot-dip galvanizing process to produce the plated steel sheet 7 will be described. The hot-dip galvanizing process may be performed by a well-known method. It suffices to use a well-known plating bath as the plating bath that is used in the hot-dip galvanizing process. For example, a plating bath containing Al with the balance being Zn and an impurity can be used as the hot-dip galvanizing bath. The impurity is, for example, Fe. The hot-dip galvanizing bath may include, in addition to Zn, Al, and Fe, one or more kinds of element selected from the group consisting of Mg, Si, Ca, Y, La, Ce, Sn, Bi, In, Cr, Ti, Ni, Co, V, Nb, Cu, Mn, Sr, Sb, Pb, and B.
In the hot-dip galvanizing process, the Al concentration, the Fe concentration, and the concentration of other elements in the hot-dip galvanizing bath, as well as the temperature, the pH, the line speed of the steel sheet 6, the impact pressure of wiping gas, and the rolling reduction at the skin pass mill 218 can be appropriately set. The Al concentration is, for example, 0.1 to 60.0% by mass. The Fe concentration is, for example, 0.01 to 0.5% by mass. In a case where the hot-dip galvanizing bath contains, in addition to Zn, Al, and Fe, one or more kinds of element selected from the group consisting of Mg, Si, Ca, Y, La, Ce, Sn, Bi, In, Cr, Ti, Ni, Co, V, Nb, Cu, Mn, Sr, Sb, Pb, and B, the content of these elements is, for example, 0.0 to 15.0% by mass in total. The temperature of the hot-dip galvanizing bath is for example, 430 to 630° C. The line speed of the steel sheet 6 is, for example, 60 to 150 m/min. The impact pressure of the wiping gas is, for example, 0 to 200 kPa. The rolling reduction at the skin pass mill 218 is, for example, 0 to 3.0%. The thickness of the plating layer that is formed by performing the hot-dip galvanizing process can be adjusted, for example, by adjusting the line speed of the steel sheet 6 into the plating solution, the impact pressure of the wiping gas, and/or the rolling reduction at the skin pass mill 218 when performing the hot-dip galvanizing process. By this means, a plating layer is formed on the surface of the steel sheet 6, and the plated steel sheet 7 can be produced.
[Grinding Process]
In the grinding process, the surface of the plating layer of the plated steel sheet 7 is ground to form a texture on the surface of the plating layer. The texture is, for example, a hairline texture. In the aforementioned apparatus for producing a textured plated steel sheet 1, the surface of the plating layer is ground by the grinding apparatus 3 having the abrasive belt 33 to form a hairline texture on the surface of the plating layer.
In the grinding process, it is possible to appropriately adjust the line speed of the plated steel sheet 7 to the grinding apparatus 3, the rotational speed of the contact rolls 32, and the rolling force with which the contact roll 32 presses against the plated steel sheet 7. The line speed of the plated steel sheet 7 to the grinding apparatus 3 is, for example, 20 to 200 m/min. The rotational speed of the contact rolls 32 is, for example, 10 to 1500 rpm. The rolling force with which the contact roll 32 presses against the plated steel sheet 7 is, for example, 0.01 to 0.10 MPa. The grinding amount of the plating layer that is ground in the grinding process can be adjusted by adjusting the rotational speed of the contact rolls 32, and the rolling force with which the contact roll 32 presses against the plated steel sheet 7. In a case where the grinding apparatus 3 includes a grinding brush, for example, the grinding amount can be adjusted by adjusting the rotational speed of the grinding brush, and/or the rolling force with which the grinding brush presses against the plated steel sheet 7.
[Plating Thickness Determining Process]
In the plating thickness determining process, first plating thickness information relating to the thickness of the plating layer of the plated steel sheet 7 at a time that is after the plating layer forming process and is before the grinding process, and second plating thickness information relating to the thickness of the plating layer of a plated steel sheet 8 after the grinding process are determined. The first plating thickness information may be determined by measuring the thickness of the plating layer of the plated steel sheet at a time that is after the plating layer forming process and is before the grinding process. The first plating thickness information may be a plating condition in the plating layer forming process. The first plating thickness information may be determined based on a plating condition in the plating layer forming process. The second plating thickness information may be determined by measuring the thickness of the plating layer of the plated steel sheet after the grinding process.
[Adjusting Process]
In the adjusting process, the plating amount of the plating layer formed in the plating layer forming process, and the grinding amount of the surface of the plating layer that is ground in the grinding process are adjusted based on the first and second plating thickness information.
For example, in a case where the first plating thickness information is more than a reference range and the second plating thickness information is more than a reference range, the plating amount of the plating layer formed in the plating layer forming process may be decreased and the grinding amount of the plating layer that is ground in the grinding process may be increased. In this case, the reduction of the plating amount of the plating layer that is formed in the plating layer forming process and the increase of the grinding amount of the plating layer that is ground in the grinding process may be performed at the same time. Alternatively, the first plating thickness information may be checked, and if the first plating thickness information is more than the reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be decreased while maintaining the grinding amount of the plating layer that is ground in the grinding process, and thereafter the second plating thickness information may be checked, and if the second plating thickness information is more than the reference range, the grinding amount of the plating layer that is ground in the grinding process may be increased while maintaining the plating amount of the plating layer that is formed in the plating layer forming process.
In a case where the plating apparatus 2 is the electrogalvanizing apparatus 200, for example, the plating amount of the plating layer that is formed in the plating layer forming process can be decreased by the following method. For example, the line speed (m/min) of the steel sheet 6 into the plating solution may be made faster. For example, the current density (A/dm2) may be lowered. Among these conditions, only either one of the conditions may be adjusted, or a combination of a plurality of the conditions may be adjusted. In a case where the plating apparatus 2 is the hot-dip galvanizing apparatus 210, for example, the plating amount of the plating layer that is formed in the plating layer forming process can be decreased by the following method. For example, the line speed (m/min) of the steel sheet 6 into the plating solution may be made faster. For example, the impact pressure of the wiping gas may be raised. For example, the rolling reduction at the skin pass mill 218 may be increased. Among these conditions, only any one of the conditions may be adjusted, or a combination of a plurality of the conditions may be adjusted.
In the case of increasing the grinding amount of the plating layer that is ground in the grinding process, for example, the line speed (m/min) of the plated steel sheet 7 into the grinding apparatus 3 may be made slower, the rotational speed (rpm) of the contact roll 32 may be made faster, or the rolling force (MPa) with which the contact roll 32 presses against the plated steel sheet 7 may be increased. In a case where the grinding apparatus 3 includes a grinding brush, the rotational speed of the grinding brush may be made faster, or the rolling force with which the grinding brush presses against the plated steel sheet 7 may be increased. Among these conditions, only any one of the conditions may be adjusted, or a combination of a plurality of the conditions may be adjusted.
For example, in a case where the first plating thickness information is more than the reference range and the second plating thickness information is less than the reference range, the plating amount of the plating layer formed in the plating layer forming process may be decreased and the grinding amount of the plating layer that is ground in the grinding process may be decreased. In this case, the reduction of the plating amount of the plating layer that is formed in the plating layer forming process and the reduction of the grinding amount of the plating layer that is ground in the grinding process may be performed at the same time. Alternatively, the first plating thickness information may be checked, and if the first plating thickness information is more than the reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be decreased while maintaining the grinding amount of the plating layer that is ground in the grinding process, and thereafter the second plating thickness information may be checked, and if the second plating thickness information is less than the reference range, the grinding amount of the plating layer that is ground in the grinding process may be decreased while maintaining the plating amount of the plating layer that is formed in the plating layer forming process.
In the case of decreasing the grinding amount of the plating layer that is ground in the grinding process, for example, the line speed (m/min) of the plated steel sheet 7 into the grinding apparatus 3 may be made faster, the rotational speed (rpm) of the contact roll 32 may be made slower, or the rolling force (MPa) with which the contact roll 32 presses against the plated steel sheet 7 may be lowered. In a case where the grinding apparatus 3 includes a grinding brush, the rotational speed of the grinding brush may be made slower, or the rolling force with which the grinding brush presses against the plated steel sheet 7 may be lowered. Among these conditions, only any one of the conditions may be adjusted, or a combination of a plurality of the conditions may be adjusted.
For example, in a case where the first plating thickness information is within a reference range and the second plating thickness information is more than a reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be maintained and the grinding amount of the plating layer that is ground in the grinding process may be increased.
For example, in a case where the first plating thickness information is within a reference range and the second plating thickness information is within a reference range, the plating amount of the plating layer that is formed in the plating layer forming process is maintained and the grinding amount of the plating layer that is ground in the grinding process is maintained.
For example, in a case where the first plating thickness information is within a reference range and the second plating thickness information is less than a reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be maintained and the grinding amount of the plating layer that is ground in the grinding process may be decreased.
For example, in a case where the first plating thickness information is less than a reference range and the second plating thickness information is more than a reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be increased and the grinding amount of the plating layer that is ground in the grinding process may be increased. In this case, the increasing of the plating amount of the plating layer that is formed in the plating layer forming process and the increasing of the grinding amount of the plating layer that is ground in the grinding process may be performed at the same time. Alternatively, the first plating thickness information may be checked, and if the first plating thickness information is less than the reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be increased while maintaining the grinding amount of the plating layer that is ground in the grinding process, and thereafter the second plating thickness information may be checked, and if the second plating thickness information is more than the reference range, the grinding amount of the plating layer that is ground in the grinding process may be increased while maintaining the plating amount of the plating layer that is formed in the plating layer forming process.
In a case where the plating apparatus 2 is the electrogalvanizing apparatus 200, for example, the plating amount of the plating layer that is formed in the plating layer forming process can be increased by the following method. For example, the line speed (m/min) of the steel sheet 6 into the plating solution may be made slower. For example, the current density (A/dm2) may be increased. Among these conditions, only either one of the conditions may be adjusted, or a combination of a plurality of the conditions may be adjusted. In a case where the plating apparatus 2 is the hot-dip galvanizing apparatus 210, for example, the plating amount of the plating layer that is formed in the plating layer forming process can be increased by the following method. For example, the line speed (m/min) of the steel sheet 6 into the plating solution may be made slower. For example, the impact pressure of the wiping gas may be lowered. For example, the rolling reduction at the skin pass mill 218 may be decreased. Among these conditions, only any one of the conditions may be adjusted, or a combination of a plurality of the conditions may be adjusted.
For example, in a case where the first plating thickness information is less than a reference range and the second plating thickness information is less than a reference range, the plating amount of the plating layer formed in the plating layer forming process may be increased and the grinding amount of the plating layer that is ground in the grinding process may be decreased. In this case, the increasing of the plating amount of the plating layer that is formed in the plating layer forming process and the decreasing of the grinding amount of the plating layer that is ground in the grinding process may be performed at the same time. Alternatively, the first plating thickness information may be checked, and if the first plating thickness information is less than the reference range, the plating amount of the plating layer that is formed in the plating layer forming process may be increased while maintaining the grinding amount of the plating layer that is ground in the grinding process, and thereafter the second plating thickness information may be checked, and if the second plating thickness information is less than the reference range, the grinding amount of the plating layer that is ground in the grinding process may be decreased while maintaining the plating amount of the plating layer that is formed in the plating layer forming process.
The method for producing a textured plated steel sheet of the present embodiment is performed using a continuous line-type apparatus for producing a textured plated steel sheet. Accordingly, coiling of the steel sheet and uncoiling of the steel sheet are not performed between the plating layer forming process and the grinding process. Further, in the method for producing a textured plated steel sheet of the present embodiment, in the adjusting process, the plating amount and the grinding amount are adjusted based on the first and second plating thickness information, with respect to the same steel sheet coil as the steel sheet coil from which the first and second plating thickness information were acquired.
The reference range of the first plating thickness information can be appropriately set, and is not particularly limited. For example, in a case where the first plating thickness information is a plating amount (g/m2), the reference range of the first plating thickness information may be, for example, 10 to 320 g/m2. In a case where the first plating thickness information is the current density (kA/m2) among the plating conditions at the plating apparatus 2, the reference range of the first plating thickness information may be, for example, 1 to 20 kA/m2. In a case where the first plating thickness information is the line speed (m/min) among the plating conditions at the plating apparatus 2, the reference range of the first plating thickness information may be, for example, 30 to 200 m/min. In a case where the first plating thickness information is the impact pressure (kPa) of the wiping gas among the plating conditions at the plating apparatus 2, the reference range of the first plating thickness information may be, for example, 0 to 200 kPa. In a case where the first plating thickness information is the rolling reduction at the skin pass mill 218 among the plating conditions at the plating apparatus 2, the reference range of the first plating thickness information may be, for example, 0 to 3.0%.
The reference range of the second plating thickness information can be appropriately set, and is not particularly limited. For example, in a case where the second plating thickness information is a plating amount (g/m2), the reference range of the second plating thickness information may be, for example, 5 to 300 g/m2.
As described above, in the method for producing a textured plated steel sheet of the present embodiment, in the plating thickness determining process, the first plating thickness information relating to the thickness of the plating layer before grinding is also determined, not just the second plating thickness information relating to the thickness of the plating layer after grinding, and furthermore, in the adjusting process, the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process are adjusted based on the first and second plating thickness information. By this means, in a case where a product defect occurs which is based on an insufficient thickness of the plating layer and/or an appearance defect, it is possible to quickly identify which factor(s) caused the product defect to occur from among two factors that are (1) the plating amount of the plating layer formed in the plating layer forming process, and (2) the grinding amount of the plating layer ground in the grinding process. In addition, by eliminating the cause of the product defect among the factors (1) and (2), a product defect such that the corrosion resistance decreases due to an insufficient thickness of the plating layer and/or a product defect such that an appearance defect occurs due to a texture not being sufficiently formed can be suppressed. Further, even in the case of a continuous line-type production apparatus, because the cause of a product defect can be quickly identified and fed back, the occurrence of product defects can be suppressed while also suppressing the occurrence of a decrease in the production speed.
[Regarding Control Unit]
The control unit 9 controls the plating apparatus 2 so as to adjust the plating amount of the plating layer to be formed on the surface of the steel sheet 6 by the plating apparatus 2, based on the first plating thickness information and the second plating thickness information, and controls the grinding apparatus 3 so as to adjust the grinding amount of the surface of the plating layer to be ground by the grinding apparatus 3, based on the first plating thickness information and the second plating thickness information. In a case where the apparatus for producing a textured plated steel sheet 1 includes the control unit 9, the apparatus for producing a textured plated steel sheet 1 more easily identifies the cause of product defects which are based on an insufficient thickness of a plating layer and an appearance defect. Therefore, it is easier to suppress the occurrence of a product defect such that the corrosion resistance decreases due to an insufficient thickness of a plating layer and/or a product defect such that an appearance defect occurs due to a texture not being sufficiently formed. When the apparatus for producing a textured plated steel sheet 1 includes the control unit 9, in addition to suppressing the occurrence of product defects, the apparatus for producing a textured plated steel sheet 1 can also facilitate suppressing unnecessary production costs.
Based on the first and second plating thickness information which is output from the first plating thickness determining apparatus 4 and the second plating thickness determining apparatus 5, the adjustment portion 91 determines the manner in which the plating apparatus 2 and the grinding apparatus 3 are to be controlled, and outputs the result. The plating apparatus control portion 92 controls the plating apparatus 2 based on the result determined by the adjustment portion 91. In a case where the plating apparatus 2 is the electrogalvanizing apparatus 200, the plating apparatus control portion 92, for example, controls the line speed (m/min) of the steel sheet 6 into the plating solution and/or the current density (A/dm2). In a case where the plating apparatus 2 is the hot-dip galvanizing apparatus 210, the plating apparatus control portion 92, for example, controls the line speed (m/min) of the steel sheet 6 into the plating solution, the impact pressure (kPa) of the wiping gas, and/or the rolling reduction (%) at the skin pass mill 218. By this means, the plating amount of the plating layer to be formed by the plating apparatus 2 is adjusted. The grinding apparatus control portion 93 controls the grinding apparatus 3 based on the result determined by the adjustment portion 91. In a case where the grinding apparatus 3 is the grinding apparatus 3 that includes the abrasive belt 33, the grinding apparatus control portion 93, for example, controls the line speed (m/min) of the plated steel sheet 7 to the grinding apparatus 3, the rotational speed (rpm) of the contact rolls 32, and the rolling force (MPa) with which the contact roll 32 presses against the plated steel sheet 7. In a case where the grinding apparatus 3 is the grinding apparatus 3 that includes a grinding brush, the grinding apparatus control portion 93, for example, controls the rotational speed of the grinding brush, and the rolling force with which the grinding brush presses against the plated steel sheet 7. By this means, the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3 is adjusted.
[Regarding Operations of Apparatus for Producing a Textured Plated Steel Sheet 1]
The operations of the apparatus for producing a textured plated steel sheet 1 having the configuration described above will now be described.
Referring to
The adjustment portion 91 of the control unit 9 determines grinding amount information that is information relating to a grinding amount at the grinding apparatus 3, based on the obtained first plating thickness information and second plating thickness information (S3). For example, in a case where the first and second plating thickness information are each a thickness (μm) of the plating layer, the adjustment portion 91 determines the grinding amount information (μm) by subtracting the second plating thickness information (μm) that is the thickness of the plating layer after grinding from the first plating thickness information (μm) that is the thickness of the plating layer before grinding. The same applies in a case where the first and second plating thickness information are each a plating amount (g/m2).
In a case where the first plating thickness information is a plating condition at the plating apparatus 2, the adjustment portion 91 of the control unit 9 may calculate the thickness (μm) before grinding of the plating layer or the plating amount (g/m2) before grinding of the plating layer based on the plating condition at the plating apparatus 2. The grinding amount information may be determined by subtracting a measured second plating thickness (μm) or a measured second plating amount (g/m2) from a calculated first plating thickness (μm) or a calculated first plating amount (g/m2).
The operations after the grinding amount information is determined (S3) are performed according to any one of patterns 1 to 9.
[Case of Patterns 1 to 3]
The adjustment portion 91 of the control unit 9 determines whether the second plating thickness information is within a reference range (S4 in
[Case of Pattern 1]
If the grinding amount information is more than the reference range (“more than reference range” in S5 in
In a case where the second plating thickness information is more than the reference range and the grinding amount information is more than the reference range, the plating amount of the plating layer that is formed by the plating apparatus 2 is too large, and in addition, the plating layer is being ground more than necessary by the grinding apparatus 3, and therefore there is an unnecessary increase in cost. Therefore, when taking the cost into consideration, it is preferable to change the operating conditions to decrease the plating amount of the plating layer that is formed by the plating apparatus 3 and to also decrease the grinding amount of the plating layer that is ground by the grinding apparatus 2.
According to pattern 1, instructions are issued so as to control the plating apparatus 2 so as to decrease the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to decrease the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 1, the plating apparatus control portion 92 controls the plating apparatus 2 so as to decrease the plating amount of the plating layer that is formed by the plating apparatus 2. Upon receiving the instructions according to pattern 1, the grinding apparatus control portion 93 controls the grinding apparatus 3 so as to decrease the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Pattern 2]
In a case where the grinding amount information is less than the reference range (“less than reference range” in S5 of
In a case where the second plating thickness information is more than the reference range and the grinding amount information is less than the reference range, because the surface of the plating layer is not being sufficiently ground by the grinding apparatus 3, a sufficient texture is not being formed on the surface of the plating layer, which results in an appearance defect. In this case, because the second plating thickness information is more than the reference range, it is known that a product defect is occurring which is caused by the grinding amount of the plating layer ground by the grinding apparatus 3. In this case, it is necessary to change the operating conditions so as to increase the grinding amount of the plating layer that is ground by the grinding apparatus 3 and form a sufficient texture on the surface of the plating layer.
According to pattern 2, instructions are issued so as to control the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to increase the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 2, the grinding apparatus control portion 93 controls the plating apparatus 2 so as to maintain the plating amount of the plating layer formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to increase the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Pattern 3]
In a case where the grinding amount information is within the reference range (“within reference range” in S5 of
In a case where the second plating thickness information is more than the reference range and the grinding amount information is within the reference range, because the plating amount of the plating layer that is formed by the plating apparatus 2 is too large, there is an unnecessary increase in cost. Therefore, when taking the cost into consideration, it is preferable to change the operating conditions so as to decrease the plating amount of the plating layer that is formed by the plating apparatus 2.
According to pattern 3, instructions are issued so as to control the plating apparatus 2 so as to decrease the plating amount of the plating layer formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to maintain the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 3, the plating apparatus control portion 92 controls the plating apparatus 2 so as to decrease the plating amount of the plating layer that is formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to maintain the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Patterns 4 to 6]
The adjustment portion 91 of the control unit 9 determines whether the second plating thickness information is within a reference range (S4 in
[Case of Pattern 4]
If the grinding amount information is more than the reference range (“more than reference range” in S9 in
In a case where the second plating thickness information is less than the reference range and the grinding amount information is more than the reference range, since the second plating thickness information is less than the reference range, the corrosion resistance of the textured plated steel sheet will decrease due to an insufficient final thickness of the plating layer, which will result in a product defect. Further, in this case, because the grinding amount information is more than the reference range, it is known that a product defect is occurring that is caused by the grinding amount of the plating layer that has been ground by the grinding apparatus 3. In this case, it is necessary to change the operating conditions so as to decrease the grinding amount of the plating layer that is ground by the grinding apparatus 3.
According to pattern 4, instructions are issued so as to control the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to decrease the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 4, the grinding apparatus control portion 93 controls the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to decrease the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Pattern 5]
In a case where the grinding amount information is less than the reference range (“less than reference range” in S9 of
In a case where the second plating thickness information is less than the reference range and the grinding amount information is less than the reference range, since the second plating thickness information is less than the reference range, the corrosion resistance of the textured plated steel sheet will decrease due to an insufficient final thickness of the plating layer, which will result in a product defect. In this case, in addition, since the grinding amount information is less than the reference range, the surface of the plating layer is not sufficiently ground by the grinding apparatus 3, and therefore a sufficient texture is not being formed on the surface of the plating layer, which results in an appearance defect. Further, since the second plating thickness information is less than the reference range, it is known that a product defect is occurring that is caused by both the plating amount of the plating layer that is formed by the plating apparatus 2 and the grinding amount of the plating layer that is ground by the grinding apparatus 3. In this case, it is necessary to change the operating conditions to increase the plating amount of the plating layer that is formed by the plating apparatus 2, and to increase the grinding amount of the plating layer that is ground by the grinding apparatus 3.
According to pattern 5, instructions are issued so as to control the plating apparatus 2 so as to increase the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to increase the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 5, the plating apparatus control portion 92 controls the plating apparatus 2 so as to increase the plating amount of the plating layer that is formed by the plating apparatus 2. Upon receiving the instructions according to pattern 5, the grinding apparatus control portion 93 controls the grinding apparatus 3 so as to increase the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Pattern 6]
In a case where the grinding amount information is within the reference range (“within reference range” in S9 in
In a case where the second plating thickness information is less than the reference range and the grinding amount information is within the reference range, since the second plating thickness information is less than the reference range, the corrosion resistance of the textured plated steel sheet will decrease due to an insufficient final thickness of the plating layer, which will result in a product defect. In this case, in addition, because the grinding amount information is within the reference range, it is known that the plating amount of the plating layer that is formed by the plating apparatus 2 is insufficient. In this case, it is necessary to change the operating conditions so as to increase the plating amount of the plating layer that is formed by the plating apparatus 2.
According to pattern 6, instructions are issued so as to control the plating apparatus 2 so as to increase the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to maintain the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 6, the plating apparatus control portion 92 controls the plating apparatus 2 so as to increase the plating amount of the plating layer that is formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to maintain the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Patterns 7 to 9]
The adjustment portion 91 of the control unit 9 determines whether the second plating thickness information is within a reference range (S4 in
[Case of Pattern 7]
In a case where the grinding amount information is more than the reference range (“more than reference range” in S13 in
In a case where the second plating thickness information is within the reference range and the grinding amount information is more than the reference range, the surface of the plating layer is being grinded by more than the necessary amount by the grinding apparatus 3. Consequently, there is an unnecessary increase in cost. Therefore, when taking the cost into consideration, it is preferable to decrease the grinding amount of the plating layer that is ground by the grinding apparatus 3.
According to pattern 7, instructions are issued so as to control the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to decrease the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 7, the grinding apparatus control portion 93 controls the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to decrease the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Pattern 8]
In a case where the grinding amount information is less than the reference range (“less than reference range” in S13 in
In a case where the second plating thickness information is within the reference range and the grinding amount information is less than the reference range, since the grinding amount information is less than the reference range, the surface of the plating layer is not being sufficiently ground by the grinding apparatus 3, and hence a sufficient texture is not formed on the surface of the plating layer, which results in an appearance defect. Further, in this case, since the second plating thickness information is within the reference range, it is known that a product defect is occurring that is caused by the grinding amount of the plating layer that is ground by the grinding apparatus 3. In this case, it is necessary to increase the grinding amount of the plating layer that is ground by the grinding apparatus 3.
According to pattern 8, instructions are issued so as to control the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to increase the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 8, the grinding apparatus control portion 93 controls the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to increase the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
[Case of Pattern 9]
In a case where the grinding amount information is within the reference range (“within reference range” in S13 in
In a case where the second plating thickness information is within the reference range and the grinding amount information is within the reference range, it is known that a product defect which is based on either an insufficient final thickness of the plating layer or an appearance defect is not occurring, and in addition, that the cost is also being appropriately maintained. In this case, it suffices to maintain the operating conditions.
According to pattern 9, instructions are issued so as to control the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and so as to control the grinding apparatus 3 so as to maintain the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3. Upon receiving the instructions according to pattern 9, the plating apparatus control portion 92 controls the plating apparatus 2 so as to maintain the plating amount of the plating layer that is formed by the plating apparatus 2, and controls the grinding apparatus 3 so as to maintain the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3.
By performing the operations described above, the apparatus for producing a textured plated steel sheet 1 of the present embodiment produces a textured plated steel sheet 8 while using the control unit 9 to control the plating apparatus 2 so as to adjust the plating amount of the plating layer that is formed on the surface of the steel sheet 6 by the plating apparatus 2 and to control the grinding apparatus 3 so as to adjust the grinding amount of the surface of the plating layer that is ground by the grinding apparatus 3, based on the first plating thickness information and the second plating thickness information. Thus, it is even easier to identify the cause of product defects which are based on an insufficient thickness of a plating layer and an appearance defect. In this case, it is even easier to suppress the occurrence of a product defect such that the corrosion resistance decreases due to an insufficient thickness of a plating layer and/or a product defect such that an appearance defect occurs due to the texture not being sufficiently formed. In a case where the control unit 9 is provided, the apparatus for producing a textured plated steel sheet 1 can also easily suppress production costs in addition to suppressing the occurrence of product defects.
[Method for Producing Textured Plated Steel Sheet]
A method for producing a textured plated steel sheet that includes the use of the control unit 9 of the present embodiment is the same as in the first embodiment except that the apparatus for producing a textured plated steel sheet that includes the control unit 9 is used.
Although the control unit 9 is used in the second embodiment, a configuration may also be adopted in which, without using the control unit 9, the grinding amount information that is information relating to the grinding amount at the grinding apparatus is determined based on the first plating thickness information and the second plating thickness information, and the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process are adjusted based on the second plating thickness information and the grinding amount information. An apparatus for producing a textured plated steel sheet 1 that is used in the third embodiment is the same as in the first embodiment.
[Method for Producing Textured Plated Steel Sheet]
A method for producing a textured plated steel sheet according to the third embodiment includes a plating layer forming process, a grinding process, a plating thickness determining process, and an adjusting process. The processes other than the adjusting process are the same as in the first embodiment. In the third embodiment, in the adjusting process, the grinding amount information that is information relating to a grinding amount at the grinding apparatus is determined, and the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process are adjusted based on the second plating thickness information and the grinding amount information.
[Adjusting Process]
In the adjusting process, the grinding amount information is determined based on the first plating thickness and the second plating thickness. The method for determining the grinding amount information is the same as in the second embodiment, except that the control unit 9 is not used. In the adjusting process, based on the second plating thickness information and the grinding amount information, the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process are adjusted based on the following patterns 1 to 9.
[Pattern 1]
In a case where the second plating thickness information is more than the reference range and the grinding amount information is more than the reference range, adjusting is performed so as to decrease the plating amount of the plating layer that is formed in the plating layer forming process and to decrease the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for decreasing the plating amount of the plating layer that is formed in the plating layer forming process, and the adjustment method for decreasing the grinding amount of the surface of the plating layer that is ground in the grinding process are the same as in the first embodiment.
[Pattern 2]
In a case where the second plating thickness information is more than the reference range and the grinding amount information is less than the reference range, adjusting is performed so as to maintain the plating amount of the plating layer that is formed in the plating layer forming process and to increase the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for increasing the grinding amount of the surface of the plating layer that is ground in the grinding process is the same as in the first embodiment.
[Pattern 3]
In a case where the second plating thickness information is more than the reference range and the grinding amount information is within the reference range, adjusting is performed so as to decrease the plating amount of the plating layer that is formed in the plating layer forming process and to maintain the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for decreasing the plating amount of the plating layer that is formed in the plating layer forming process is the same as in the first embodiment.
[Pattern 4]
In a case where the second plating thickness information is less than the reference range and the grinding amount information is more than the reference range, adjusting is performed so as to maintain the plating amount of the plating layer that is formed in the plating layer forming process and to decrease the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for decreasing the grinding amount of the surface of the plating layer that is ground in the grinding process is the same as in the first embodiment.
[Pattern 5]
In a case where the second plating thickness information is less than the reference range and the grinding amount information is less than the reference range, adjusting is performed so as to increase the plating amount of the plating layer that is formed in the plating layer forming process and to increase the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for increasing the plating amount of the plating layer that is formed in the plating layer forming process, and the adjustment method for increasing the grinding amount of the surface of the plating layer that is ground in the grinding process are the same as in the first embodiment.
[Pattern 6]
In a case where the second plating thickness information is less than the reference range and the grinding amount information is within the reference range, adjusting is performed so as to increase the plating amount of the plating layer that is formed in the plating layer forming process and to maintain the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for increasing the plating amount of the plating layer that is formed in the plating layer forming process is the same as in the first embodiment.
[Pattern 7]
In a case where the second plating thickness information is within the reference range and the grinding amount information is more than the reference range, adjusting is performed so as to maintain the plating amount of the plating layer that is formed in the plating layer forming process and to decrease the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for decreasing the grinding amount of the surface of the plating layer that is ground in the grinding process is the same as in the first embodiment.
[Pattern 8]
In a case where the second plating thickness information is within the reference range and the grinding amount information is less than the reference range, adjusting is performed so as to maintain the plating amount of the plating layer that is formed in the plating layer forming process and to increase the grinding amount of the surface of the plating layer that is ground in the grinding process. The adjustment method for increasing the grinding amount of the surface of the plating layer that is ground in the grinding process is the same as in the first embodiment.
[Pattern 9]
In a case where the second plating thickness information is within the reference range and the grinding amount information is within the reference range, adjusting is performed so as to maintain the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process. Specifically, the plating conditions in the plating layer forming process and the grinding conditions in the grinding process are maintained.
According to the production processes described above, in addition to suppressing the occurrence of product defects, the production cost can also be suppressed.
The apparatus for producing a textured plated steel sheet 1 may also include a coating film forming apparatus, in addition to the plating apparatus 2, the grinding apparatus 3, the first plating thickness determining apparatus 4, and the second plating thickness determining apparatus 5. The coating film forming apparatus is arranged downstream of the grinding apparatus 3, and forms a coating film on the surface of the plating layer that has been ground.
[Method for Producing Textured Plated Steel Sheet]
In the case of forming a coating film, the method for producing a textured plated steel sheet includes a coating film forming process in addition to the plating layer forming process, the grinding process, the plating thickness determining process, and the adjusting process.
[Coating Film Forming Process]
A well-known method may be used as the method for forming a coating film. In the case of forming an organic coating film, a coating material constituting an organic coating is prepared. The prepared coating material is applied onto the plating layer by a spray method, a roll coater method, a curtain coater method, or a dip and lift method or the like. Thereafter, the coating material on the plating layer is subjected to natural drying or to baking to form an organic coating film. The drying temperature, drying time, baking temperature, and baking time can be adjusted as appropriate.
In the case of forming an inorganic coating film as a coating film, a chemical agent for an inorganic coating film is applied onto the plating layer by a roll coater method, a dip ringer method, a spray ringer method, an electrolytic method, or the like. The chemical agent applied onto the plating layer is subjected to natural drying or to baking to form an inorganic coating film. The drying temperature, drying time, baking temperature, and baking time can be adjusted as appropriate.
The other production processes in the fourth embodiment are the same as in the first embodiment.
The apparatus for producing a textured plated steel sheet 1 may include one or a plurality of gloss meters in addition to the plating apparatus 2, the grinding apparatus 3, the first plating thickness determining apparatus 4, and the second plating thickness determining apparatus 5. Each gloss meter is arranged downstream of the grinding apparatus 3, and evaluates the appearance of the surface of the plated steel sheet having the plating layer that has been ground.
The gloss meters may be two gloss meters which are a gloss meter that measures a glossiness of the surface of the plated steel sheet in the longitudinal direction of the plated steel sheet, and a gloss meter that measures a glossiness of the surface of the plated steel sheet in the sheet width direction of the plated steel sheet. In this case, the appearance of the surface of the plated steel sheet having the plating layer that has been ground can be evaluated with greater accuracy.
[Method for Producing Textured Plated Steel Sheet]
In the case of evaluating the appearance of the surface of a plated steel sheet having a plating layer that has been ground, the method for producing a textured plated steel sheet includes an appearance evaluating process in addition to the plating layer forming process, the grinding process, the plating thickness determining process, and the adjusting process. In the appearance evaluating process, the appearance of the plated steel sheet after the grinding process is evaluated based on a glossiness.
[Appearance Evaluating Process]
In the appearance evaluating process, the appearance of the plated steel sheet after the grinding process is evaluated based on a glossiness. In the appearance evaluating process, the appearance of the plated steel sheet may be evaluated based on two glossinesses, namely, a glossiness of the surface of the plated steel sheet measured in the longitudinal direction of the plated steel sheet, and a glossiness of the surface of the plated steel sheet measured in the sheet width direction of the plated steel sheet.
[Adjusting Process]
In the method for producing a textured plated steel sheet of the present embodiment, in the adjusting process, the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process are adjusted based on the first plating thickness information, the second plating thickness information, and the glossiness of the surface of the plated steel sheet after the grinding process.
In a case where the appearance is evaluated based on the glossiness, the appearance of the plated steel sheet can be evaluated with greater accuracy compared to a case of estimating the appearance based on the first plating thickness information and the second plating thickness information. Therefore, in the case of evaluating the appearance of the plated steel sheet based on a glossiness, a stricter condition can be set with respect to a standard for the appearance of the plated steel sheet. However, in this case, a situation may occur in which, even though the first plating thickness information and the second plating thickness information are each within the relevant reference range, based on the appearance evaluation of the plated steel sheet that is based on the glossiness it is determined that the texture is not sufficiently formed and an appearance defect has occurred. In this case, the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process may be adjusted.
For example, in a case where the first plating thickness information and the second plating thickness information are within the reference range, respectively, and a texture is not sufficiently formed and the appearance evaluation of the plated steel sheet that is based on the glossiness is that the appearance is not good, the grinding amount of the plating layer that is ground in the grinding process may be increased while maintaining the plating amount of the plating layer that is formed in the plating layer forming process. A method for increasing the grinding amount of the plating layer that is ground in the grinding process is the same as in the first embodiment.
At such time, in a case where, although the second plating thickness information is within the reference range, the second plating thickness information is close to the lower limit value of the reference range or the like, if it is expected that the second plating thickness information will become less than the reference range if the grinding amount of the plating layer that is ground in the grinding process is increased while maintaining the plating amount of the plating layer that is formed in the plating layer forming process, the plating amount of the plating layer that is formed in the plating layer forming process may be increased and the grinding amount of the plating layer that is ground in the grinding process may be increased. A method for increasing the plating amount of the plating layer that is formed in the plating layer forming process is the same as in the first embodiment.
Alternatively, an operation table that includes plating conditions in the plating layer forming process which correspond to glossiness, and grinding conditions in the grinding process which correspond to glossiness may be created, and the plating amount of the plating layer that is formed in the plating layer forming process and the grinding amount of the surface of the plating layer that is ground in the grinding process may be adjusted based on a measured glossiness.
The other production processes in the fifth embodiment are the same as in the first embodiment.
Embodiments of the present disclosure have been described above. However, the foregoing embodiments are merely examples for implementing the present disclosure. Accordingly, the present disclosure is not limited to the above embodiments, and the above embodiments can be appropriately modified and implemented within a range that does not deviate from the gist of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-045928 | Mar 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/008176 | 2/28/2022 | WO |
