Continuous hot galvanizing process for steel strip

Abstract

The invention discloses a continuous hot galvanizing process for a steel strip, which relates to the technical field of hot galvanizing and comprises the following steps: carrying out rust removal pretreatment on the steel strip; carrying out heating pretreatment on the tested steel strip and obtaining preheating parameters; using a preferable immersion plating method to obtain preferable preheating time and preferable preheating temperature; the derusted steel strip is galvanized on the basis of the optimal preheating time and the optimal preheating temperature, and the galvanized derusted steel strip is cooled and passivated; the method is used for solving the problems that in an existing steel strip hot galvanizing process, the thickness of a zinc layer on the surface of a steel strip cannot be effectively controlled during galvanizing based on pretreatment data and galvanizing data of the steel strip, the surface of the zinc layer is rough or pulverized due to the fact that an alloy layer is too thick, and consequently the zinc layer is prone to being broken or the bonding strength of the zinc layer is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of hot-dip galvanizing, in particular to a continuous hot-dip galvanizing process for a steel strip. Background Art

[0002] Hot-dip galvanizing is a process in which steel parts are immersed in molten zinc liquid to form a zinc alloy coating with good adhesion on the surface of the steel products through the reaction and diffusion between iron and zinc. This method can not only effectively prevent the corrosion of steel, but also provide a uniform and highly adhesive coating with the advantage of long service life; hot-dip galvanizing is widely used in various metal structural facilities and is an effective way to prevent metal corrosion. Its advantages include uniform coating, strong adhesion, long service life, etc. It is one of the most effective means to delay environmental corrosion of steel materials.

[0003] Existing methods for hot-dip galvanizing of steel strips are usually used to improve the surface quality of galvanized steel strips and to prevent the occurrence of missed plating. For example, after cleaning the pre-galvanized steel strips, the PVD vacuum nickel plating unit is first used to pre-nickel plate the steel strips, and then the pre-nickel plated steel strips are annealed before galvanizing, thereby avoiding missed plating during the galvanizing process. Although this improved method can improve the surface quality of the steel strip after galvanizing and the galvanizing completeness, it is unable to effectively control the thickness of the zinc layer on the surface of the steel strip during galvanizing based on the pretreatment data and galvanizing data of the steel strips. There may be problems such as roughness or powderization of the zinc layer due to the excessive thickness of the alloy layer, which makes the zinc layer easy to break or reduces the bonding strength of the zinc layer. For example, in a patent application with publication number CN105112914A, a continuous hot-dip galvanizing device and a continuous hot-dip galvanizing method are disclosed. This scheme is to pass By using the PVD vacuum nickel plating unit to pre-nickel-plate the steel strip, the problem of selective external oxidation of alloy elements in the steel during the annealing process and deterioration of the wettability of the steel strip is effectively avoided, and the phenomenon of missed plating during the galvanizing of high-strength steel strip is avoided, thereby improving the surface quality of the high-strength galvanized steel strip. Other improvements for hot-dip galvanizing are usually improvements in impurity removal before galvanizing the steel strip, such as pushing impurities floating on the surface of the zinc liquid to a position away from the steel strip through vibration to avoid defects on the surface of the hot-dip galvanized sheet due to slag sticking, ash sticking and missed plating. This improvement method still cannot effectively control the thickness of the zinc layer on the surface of the steel strip during galvanizing based on the pretreatment data and galvanizing data of the steel strip. There may be problems such as roughness or powderization of the zinc layer due to excessive thickness of the alloy layer, which makes the zinc layer easy to break or reduces the bonding strength of the zinc layer. In view of this, it is necessary to improve the existing hot-dip galvanizing process for steel strip. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the prior art to at least a certain extent, and proposes a continuous hot-dip galvanizing process for steel strip to solve the problem in the existing hot-dip galvanizing process for steel strip that it is impossible to effectively control the thickness of the zinc layer on the surface of the steel strip during galvanizing based on the pretreatment data and galvanizing data of the steel strip, and that the surface of the zinc layer may be rough or powdered due to the excessive thickness of the alloy layer, thereby making the zinc layer easy to break or reducing the bonding strength of the zinc layer.

[0005] To achieve the above object, the present application provides a continuous hot-dip galvanizing process for a steel strip, comprising the following steps: Performing rust removal pretreatment on the galvanized steel strip, and recording the rust removal pretreatment steel strip as a rust removal steel strip; Performing heat pretreatment on the steel strip that can be tested, obtaining preheating parameters based on the duration of the heat pretreatment and the temperature of the heat pretreatment, and recording the steel strip after the preheat treatment as a pretreated steel strip; Immersing the pretreated steel strip in molten zinc solution, using an optimal immersion plating method to obtain an optimal preheating time and an optimal preheating temperature; The derusted steel strip is galvanized based on the preferred preheating time and the preferred preheating temperature, and the galvanized derusted steel strip is cooled and passivated.

[0006] Further, the galvanized steel strip is subjected to rust removal pretreatment, and the rust removal pretreatment steel strip is recorded as a rust removal steel strip, including: The rust removal pretreatment is performed on the galvanized steel strip, and the rust removal pretreatment includes: immersing the galvanized steel strip in an alkaline electrolyte based on an electrolytic degreasing method, and passing direct current into the alkaline electrolyte until the electrolytic degreasing is completed; Use clean water to clean the electrolytically degreased steel strip. When the degreaser on the surface of the galvanized steel strip is completely removed, put the steel strip into a dilute hydrochloric acid solution for rust removal. When bubbles are generated on the surface of the steel strip to be galvanized in the dilute hydrochloric acid solution, the number of bubbles on the surface of the steel strip to be galvanized is obtained in real time, and when the number of bubbles in real time decreases, a corrosion inhibitor is added to the dilute hydrochloric acid solution until there are no bubbles on the surface of the steel strip to be galvanized; The steel strip that has been rust-removed is cleaned with clean water, and the moisture on the surface of the steel strip is dried. The steel strip at this time is recorded as a rust-removed steel strip.

[0007] Furthermore, the steel strip capable of being tested is subjected to a heating pretreatment, and the preheating parameters are obtained based on the duration of the heating pretreatment and the temperature of the heating pretreatment, including: The maximum temperature at which the steel strip can be heated is recorded as the maximum preheating temperature; a plane rectangular coordinate system is established and recorded as a preheating segmented coordinate system, wherein the unit of the X-axis of the preheating segmented coordinate system is time, and the unit of the Y-axis is temperature; the rust-removed steel strip is heated, and a corresponding curve is drawn in the preheating segmented coordinate system based on the heating time and the temperature of the surface of the rust-removed steel strip, which is recorded as a preheating temperature curve; The maximum number of steel strips that can be tested is recorded as k; the maximum value of the horizontal axis in the preheating temperature curve is recorded as X max , the maximum value of the ordinate in the preheating temperature curve is recorded as Y max .

[0008] Further, the steel strip capable of being tested is subjected to a heating pretreatment, and obtaining the preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment further includes: Set the X axis from 0 to X max The interval is divided into k equal parts and recorded from left to right as horizontal interval HQ1 to horizontal interval HQ k ; For any horizontal interval HQ: record the point with the largest slope in the preheating temperature curve in the horizontal interval HQ as the horizontal fastest segmentation point; obtain the horizontal fastest segmentation point in each horizontal interval HQ; Set the Y axis from 0 to Y max The interval is divided into k parts, and recorded from bottom to top as vertical interval ZQ1 to vertical interval ZQ k ; For any longitudinal interval ZQ: record the point with the largest slope in the preheating temperature curve in the longitudinal interval ZQ as the longitudinal fastest dividing point; obtain the longitudinal fastest dividing point in each longitudinal interval ZQ.

[0009] Further, the steel strip capable of being tested is subjected to a heating pretreatment, and obtaining the preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment further includes: Sequentially for horizontal intervals HQ1 to HQ k The fastest transverse segmentation points in are processed by mean elimination; the mean elimination process is as follows: obtain the fastest longitudinal segmentation point with the smallest difference in ordinate with the fastest transverse segmentation point, and record it as the mean elimination point of the fastest transverse segmentation point; record (X0, Y0) as the mean segmentation point, and eliminate the fastest transverse segmentation point and its corresponding mean elimination point from all the fastest transverse segmentation points and all the fastest longitudinal segmentation points, where X0 is the mean of the abscissa of the fastest transverse segmentation point and the abscissa of the mean elimination point of the fastest transverse segmentation point, and Y0 is the mean of the ordinate of the fastest transverse segmentation point and the ordinate of the mean elimination point of the fastest transverse segmentation point; Get all mean split points after mean elimination.

[0010] Further, the steel strip capable of being tested is subjected to a heating pretreatment, and obtaining the preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment further includes: Obtain k steel strips that can be tested, and record the horizontal coordinates and vertical coordinates corresponding to all mean split points as the preheating parameters of each steel strip; The steel strip is heated based on the preheating parameters of each steel strip, and the heated steel strip is recorded as a pretreated steel strip.

[0011] Further, the pretreated steel strip is immersed in molten zinc solution, and the preferred preheating time and the preferred preheating temperature are obtained by using the preferred immersion plating method, which comprises: For any pretreated steel strip: immerse the pretreated steel strip in molten zinc liquid, and start timing after the pretreated steel strip is immersed in the molten zinc liquid. When zinc ash is generated on the surface of the zinc tank, the time point recorded at this time is recorded as the galvanizing reaction point; when the zinc ash on the surface of the zinc tank stops generating, the time point recorded at this time is recorded as the galvanizing end point, and the pretreated steel strip is taken out of the zinc liquid, and the coating thickness on the surface of the pretreated steel strip at this time is recorded as the zinc layer thickness, wherein the zinc tank is used to store molten zinc liquid; Obtain the galvanizing reaction point, galvanizing end point and zinc layer thickness corresponding to all pretreated steel strips.

[0012] Further, the preferred immersion plating method comprises: For any pretreated steel strip, the value corresponding to the galvanizing end point of the pretreated steel strip minus the time corresponding to the galvanizing reaction point is recorded as the galvanizing time; the time corresponding to the galvanizing reaction point is recorded as the start time, and the value of the galvanizing time divided by the start time is recorded as the galvanizing reaction ratio; A plane rectangular coordinate system is established, which is recorded as the comprehensive screening coordinate system, wherein the X-axis and the Y-axis of the comprehensive screening coordinate system are both constant axes; an equilateral triangle is drawn with the coordinate origin as the center in the comprehensive screening coordinate system, which is recorded as the screening triangle; the three vertices of the screening triangle are recorded as the thickness vertex, the ratio vertex and the time vertex respectively; the standard range of the zinc layer thickness is obtained based on the galvanizing standard, and when the zinc layer thickness of the pretreated steel strip is within the standard range of the zinc layer thickness, the thickness parameter is set to 0; when the zinc layer thickness of the pretreated steel strip is outside the standard range of the zinc layer thickness, the thickness parameter is set to the minimum value of the difference between the zinc layer thickness and the standard range of the zinc layer thickness.

[0013] Further, the preferred immersion plating method also includes: A ray is made from the coordinate origin as the endpoint in the direction of the thickness vertex, and the point whose length with the coordinate origin is the thickness parameter in the ray is recorded as the thickness screening point; a ray is made from the coordinate origin as the endpoint in the direction of the ratio vertex, and the point whose length with the coordinate origin is the galvanizing reaction ratio in the ray is recorded as the ratio screening point; a ray is made from the coordinate origin as the endpoint in the direction of the time vertex, and the point whose length with the coordinate origin is the total plating time in the ray is recorded as the time screening point, wherein the total plating time is the sum of the horizontal coordinate corresponding to the preheating parameter of the pretreated steel strip and the time corresponding to the galvanizing end point, and the unit of the total plating time is hour; The area of ​​the triangle formed by the thickness screening point, the ratio screening point and the time screening point is recorded as the screening parameter of the pretreated steel strip; The screening parameters of all pretreated steel strips are obtained, and the pretreated steel strip with the smallest screening parameters is recorded as the preferred treated steel strip; the horizontal coordinate and the vertical coordinate in the preheating parameters of the preferred treated steel strip are recorded as the preferred preheating time and the preferred preheating temperature, respectively.

[0014] Further, the rust-removed steel strip is galvanized based on the preferred preheating time and the preferred preheating temperature, and the galvanized rust-removed steel strip is cooled and passivated, including: Based on the preferred preheating time and the preferred preheating temperature, the rust-removed steel strip is preheated before being immersed in the molten zinc liquid; when the rust-removed steel strip is heated to the preferred preheating temperature at the preferred preheating time, the rust-removed steel strip is immersed in the molten zinc liquid until zinc ash on the surface of the zinc tank stops being generated, and the rust-removed steel strip is taken out from the zinc liquid; The rust-removed steel strip taken out from the zinc liquid is placed in cooling water for cooling treatment; The rust-removed steel strip taken out from the cooling water is immersed in the passivation liquid for passivation treatment.

[0015] Beneficial effects of the present invention: the present invention first performs rust removal pretreatment on the steel strip to be galvanized, and records the steel strip that has undergone rust removal pretreatment as a rust-removed steel strip; then performs heat pretreatment on the steel strip that can be tested, obtains preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment, and records the steel strip that has undergone the preheating treatment as a pretreated steel strip. The advantage of this is that by performing heat pretreatment on the steel strip that can be tested and obtaining preheating parameters, a variety of preheating conditions that can be used to preheat the steel strip before galvanizing can be obtained, which is helpful in selecting preheating conditions that can plate a zinc layer of a specified thickness from a variety of preheating conditions in subsequent analysis, thereby improving the galvanizing efficiency and controlling the zinc layer thickness on the surface of the steel strip during galvanizing based on the pretreatment data and the galvanizing data of the steel strip, thereby preventing problems with the zinc layer strength caused by an excessively thick zinc layer; The present invention also immerses the pretreated steel strip into molten zinc liquid, and uses an optimal immersion plating method to obtain an optimal preheating time and an optimal preheating temperature; finally, the rust-removed steel strip is galvanized based on the optimal preheating time and the optimal preheating temperature, and the galvanized rust-removed steel strip is cooled and passivated. The advantage of this is that by obtaining the optimal preheating time and the optimal preheating temperature, a zinc layer of a compliant thickness can be plated during galvanizing, while ensuring that the galvanizing efficiency and the total galvanizing time are both optimal, so as to improve the overall galvanizing efficiency while controlling the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a flow chart of the steps of the method of the present invention; Figure 2 A schematic diagram of obtaining the mean segmentation point of the present invention; Figure 3 It is a schematic diagram of obtaining the screening parameters of the present invention; Figure 4 It is a schematic structural diagram of the electronic device of the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1, first aspect, please refer to Figure 1 As shown, the present application provides a continuous hot-dip galvanizing process for steel strip, comprising the following steps: Step S1, performing rust removal pretreatment on the galvanized steel strip, and recording the rust-removed steel strip as the rust-removed steel strip; Step S1 includes: Step S101, performing rust removal pretreatment on the galvanized steel strip, the rust removal pretreatment includes: immersing the galvanized steel strip in an alkaline electrolyte based on an electrolytic degreasing method, and passing direct current into the alkaline electrolyte until the electrolytic degreasing is completed; In the specific implementation process, the steel strip can be degreased according to the degreasing method that can be realized in the actual process. Through the degreasing treatment, the impurities on the surface of the steel strip can be decomposed to ensure that the surface of the steel strip is cleaner during the subsequent galvanizing, and to prevent the problem of uneven zinc layer after galvanizing and weak zinc layer bonding due to surface impurities; Step S102, using clean water to wash the steel strip that has been electrolytically degreased, and when the degreasing agent on the surface of the steel strip to be galvanized is completely removed, the steel strip is placed in a dilute hydrochloric acid solution for rust removal; Step S103, when bubbles are generated on the inner surface of the steel strip to be galvanized in the dilute hydrochloric acid solution, the number of bubbles on the surface of the steel strip to be galvanized is obtained in real time, and when the real-time number of bubbles decreases, a corrosion inhibitor is added to the dilute hydrochloric acid solution until there are no bubbles on the surface of the steel strip to be galvanized; In the specific implementation process, in actual application, the number of bubbles in the video can be extracted by video recording using existing image recognition technology. The image recognition technology uses existing contour extraction technology to obtain the number of bubbles through the number of contour extraction, so as to achieve the purpose of obtaining the number of bubbles on the surface of the steel strip to be galvanized in real time. When there are no bubbles on the surface of the steel strip to be galvanized, it means that the rust removal treatment has been completed, and the steel strip can be taken out of the dilute hydrochloric acid solution; by adding a corrosion inhibitor, the steel strip can be prevented from being placed in the dilute hydrochloric acid solution for too long, which may cause the steel strip to be corroded; Step S104, using clean water to clean the steel strip after the rust removal treatment, and drying the moisture on the surface of the steel strip, and the steel strip at this time is recorded as the rust-removed steel strip.

[0019] Step S2, performing heat pretreatment on the steel strip that can be tested, obtaining preheating parameters based on the duration of the heat pretreatment and the temperature of the heat pretreatment, and recording the steel strip after the preheat treatment as the pretreated steel strip; Step S2 includes: step S201, recording the maximum temperature at which the steel strip can be heated as the maximum preheating temperature; establishing a plane rectangular coordinate system and recording it as a preheating segmented coordinate system, wherein the unit of the X-axis of the preheating segmented coordinate system is time, and the unit of the Y-axis is temperature; heating the rust-removed steel strip, and drawing a corresponding curve in the preheating segmented coordinate system based on the heating time and the temperature of the surface of the rust-removed steel strip, recording it as a preheating temperature curve; In the specific implementation process, for example, during a data analysis, the preheating temperature curve obtained is as follows: Figure 2 As shown, the maximum number of steel strips that can be tested at the same time is 4. Figure 2 In the figure, curve YW is the preheating temperature curve, and all the dotted lines parallel to the X-axis and the Y-axis are used to divide the temperature from 0 to X. max and 0 to Y max The straight line, and Xmax is X max , Ymax is Y max; For the horizontal interval HQ2 formed by XX1 and XX2, through analysis, it can be obtained that point ZZ1 is the horizontal fastest dividing point of the horizontal interval HQ2, and for the longitudinal interval ZQ2 formed by YY1 and YY2, through analysis, it can be obtained that point ZZ2 is the longitudinal fastest dividing point of the longitudinal interval ZQ2; based on subsequent analysis, the longitudinal fastest dividing point with the smallest difference in ordinate with the horizontal fastest dividing point of the horizontal interval HQ2 is the longitudinal fastest dividing point of the longitudinal interval ZQ2, then the abscissa of the mean dividing point can be the average of the abscissas of point ZZ1 and point ZZ2, and the ordinate of the mean dividing point can be the average of the ordinates of point ZZ1 and point ZZ2; Step S202, the maximum number of steel strips that can be tested is recorded as k; the maximum value of the horizontal axis in the preheating temperature curve is recorded as X max , the maximum value of the ordinate in the preheating temperature curve is recorded as Y max ; Step S203: set the X axis from 0 to X max The interval is divided into k equal parts and recorded from left to right as horizontal interval HQ1 to horizontal interval HQ k ; For any horizontal interval HQ: record the point with the largest slope in the preheating temperature curve in the horizontal interval HQ as the horizontal fastest segmentation point; obtain the horizontal fastest segmentation point in each horizontal interval HQ; Step S204: set the Y axis from 0 to Y max The interval is divided into k parts, and recorded from bottom to top as vertical interval ZQ1 to vertical interval ZQ k ; For any longitudinal interval ZQ: record the point with the largest slope in the preheating temperature curve in the longitudinal interval ZQ as the longitudinal fastest segmentation point; obtain the longitudinal fastest segmentation point in each longitudinal interval ZQ; Step S205: sequentially perform the following operations on the horizontal intervals HQ1 to HQ k The fastest transverse segmentation points in are processed by mean elimination; the mean elimination process is as follows: obtain the fastest longitudinal segmentation point with the smallest difference in ordinate with the fastest transverse segmentation point, and record it as the mean elimination point of the fastest transverse segmentation point; record (X0, Y0) as the mean segmentation point, and eliminate the fastest transverse segmentation point and its corresponding mean elimination point from all the fastest transverse segmentation points and all the fastest longitudinal segmentation points, where X0 is the mean of the abscissa of the fastest transverse segmentation point and the abscissa of the mean elimination point of the fastest transverse segmentation point, and Y0 is the mean of the ordinate of the fastest transverse segmentation point and the ordinate of the mean elimination point of the fastest transverse segmentation point; In the specific implementation process, by obtaining the mean segmentation point, it is possible to obtain multiple critical points at which the temperature of the steel strip changes greatly when it is preheated, as reflected by the preheating temperature curve, so as to help screen out the most suitable preheating temperature for galvanizing from multiple critical points with large temperature changes in subsequent analysis, so as to use the preheated steel strip for galvanizing to improve the galvanizing efficiency; and the purpose of obtaining the critical point with large temperature change is to ensure that the screened temperature is the temperature at which the steel strip can quickly absorb heat in the zinc liquid after being preheated, so as to increase the heating rate of the steel strip after being placed in the zinc liquid, thereby improving the galvanizing efficiency; Step S206, obtaining all mean segmentation points obtained after mean elimination processing; Step S207, obtaining k steel strips that can be tested, and recording the horizontal coordinates and vertical coordinates corresponding to all mean value segmentation points as the preheating parameters of each steel strip; Step S208, heating the steel strips based on the preheating parameters of each steel strip, and recording the heated steel strips as pretreated steel strips.

[0020] Step S3, immersing the pretreated steel strip in molten zinc liquid, and using the preferred immersion plating method to obtain the preferred preheating time and the preferred preheating temperature; Step S3 includes: Step S301, for any pretreated steel strip: immersing the pretreated steel strip in molten zinc liquid, and starting the timing after the pretreated steel strip is immersed in the molten zinc liquid, when zinc ash is generated on the surface of the zinc tank, the time point recorded at this time is recorded as the galvanizing reaction point; when the zinc ash on the surface of the zinc tank stops generating, the time point recorded at this time is recorded as the galvanizing end point, and the pretreated steel strip is taken out of the zinc liquid, and the coating thickness on the surface of the pretreated steel strip at this time is recorded as the zinc layer thickness, wherein the zinc tank is used to store molten zinc liquid; Step S302, obtaining the galvanizing reaction point, galvanizing end point and zinc layer thickness corresponding to all pretreated steel strips.

[0021] Step S303, preferably the immersion plating method is as follows: Step S3031, for any pretreated steel strip, the value corresponding to the galvanizing end point of the pretreated steel strip minus the time corresponding to the galvanizing reaction point is recorded as the galvanizing time; the time corresponding to the galvanizing reaction point is recorded as the start time, and the value of the galvanizing time divided by the start time is recorded as the galvanizing reaction ratio; In the specific implementation process, for example, in a data processing, the time corresponding to the galvanizing end point is 3 minutes, and the time of the galvanizing reaction point is 2 minutes. Then, by calculation, it can be obtained that the galvanizing time is 1 minute, the start time is 2 minutes, and the galvanizing reaction ratio is 0.5. By obtaining the galvanizing reaction ratio, the ratio of the time when the steel strip reacts with the zinc liquid in the zinc liquid to the time before the reaction with the zinc liquid can be obtained. The smaller the galvanizing reaction ratio is, the less time the steel strip reacts with the zinc liquid in the zinc liquid, and the faster the reaction rate is. Step S3032, establish a plane rectangular coordinate system, recorded as a comprehensive screening coordinate system, wherein the X-axis and the Y-axis of the comprehensive screening coordinate system are both constant axes; draw an equilateral triangle with the coordinate origin as the center in the comprehensive screening coordinate system, recorded as a screening triangle; record the three vertices of the screening triangle as the thickness vertex, the ratio vertex and the time vertex respectively; obtain the standard range of zinc layer thickness based on the galvanizing standard, and when the zinc layer thickness of the pretreated steel strip is within the standard range of zinc layer thickness, set the thickness parameter to 0; when the zinc layer thickness of the pretreated steel strip is outside the standard range of zinc layer thickness, set the thickness parameter to the minimum value of the difference between the zinc layer thickness and the standard range of zinc layer thickness; Step S3033, draw a ray with the coordinate origin as the endpoint in the direction of the thickness vertex, and record the point whose length with the coordinate origin is the thickness parameter in the ray as the thickness screening point; draw a ray with the coordinate origin as the endpoint in the direction of the ratio vertex, and record the point whose length with the coordinate origin is the galvanizing reaction ratio in the ray as the ratio screening point; draw a ray with the coordinate origin as the endpoint in the direction of the time vertex, and record the point whose length with the coordinate origin is the total plating time in the ray as the time screening point, wherein the total plating time is the sum of the horizontal coordinate corresponding to the preheating parameter of the pretreated steel strip and the time corresponding to the galvanizing end point, and the unit of the total plating time is hour; In the specific implementation process, for example, during a data processing, the comprehensive screening coordinate system obtained is as follows Figure 3 As shown, the triangle formed by DD1, DD2 and DD3 is a screening triangle. Through data processing, it is obtained that the thickness screening point, the ratio screening point and the time screening point are the points corresponding to the points DD4, DD5 and DD6 respectively. Then the area of ​​the triangle formed by the points DD4, DD5 and DD6 can be recorded as the screening parameter of the pre-treated steel strip; the screening parameter obtained by the above processing is a screening parameter obtained by combining whether the thickness meets the specifications, the galvanizing efficiency and the total galvanizing time. The smaller the screening parameter, the more efficient and compliant the galvanizing method corresponding to the screening parameter is. Step S3034, recording the area of ​​the triangle formed by the thickness screening point, the ratio screening point and the time screening point as the screening parameter of the pre-treated steel strip; Step S3035, obtaining the screening parameters of all pretreated steel strips, and recording the pretreated steel strip with the smallest screening parameters as the preferred treated steel strip; recording the horizontal coordinate and the vertical coordinate in the preheating parameters of the preferred treated steel strip as the preferred preheating time and the preferred preheating temperature, respectively.

[0022] Step S4, galvanizing the rust-removed steel strip based on the preferred preheating time and the preferred preheating temperature, and cooling and passivating the galvanized rust-removed steel strip; Step S4 includes: Step S401, preheating the rust-removed steel strip before immersing it in molten zinc liquid based on the preferred preheating time and the preferred preheating temperature; when the rust-removed steel strip is heated to the preferred preheating temperature at the preferred preheating time, immersing the rust-removed steel strip in the molten zinc liquid until zinc ash on the surface of the zinc tank stops being generated, and taking the rust-removed steel strip out of the zinc liquid; Step S402, placing the rust-removed steel strip taken out from the zinc liquid into cooling water for cooling treatment; Step S403, the rust-removed steel strip taken out from the cooling water is immersed in a passivation solution for passivation treatment.

[0023] Example 2, please refer to Figure 4 As shown, Figure 4 The structural schematic diagram of an electronic device is illustrated, and the electronic device may include: a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus. The memory stores computer-readable instructions, and the processor can call the instructions in the memory. When the computer-readable instructions are executed by the processor, the steps in a continuous hot-dip galvanizing process for steel strip are executed to achieve the following functions: first, the rust removal pretreatment is performed on the steel strip to be galvanized, and the steel strip subjected to the rust removal pretreatment is recorded as the rust removal steel strip; then, the steel strip capable of being tested is subjected to heat pretreatment, and the preheating parameters are obtained based on the duration of the heat pretreatment and the temperature of the heat pretreatment, and the steel strip subjected to the preheating treatment is recorded as the pretreated steel strip; the pretreated steel strip is also immersed in molten zinc liquid, and the preferred preheating time and the preferred preheating temperature are obtained by using the preferred immersion plating method; finally, the rust removal steel strip is subjected to galvanizing based on the preferred preheating time and the preferred preheating temperature, and the galvanized rust removal steel strip is subjected to cooling treatment and passivation treatment.

[0024] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0025] Embodiment 3, the present application also provides a computer-readable storage medium, the present application provides a storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps in the above continuous hot-dip galvanizing process for steel strip are executed to achieve the following functions: first, the steel strip to be galvanized is pretreated for rust removal, and the steel strip pretreated for rust removal is recorded as a rust-removed steel strip; then, the steel strip that can be tested is pretreated for heat treatment, and preheating parameters are obtained based on the duration of the heating pretreatment and the temperature of the heating pretreatment, and the steel strip after the preheating treatment is recorded as a pretreated steel strip; the pretreated steel strip is also immersed in molten zinc liquid, and an optimal preheating time and an optimal preheating temperature are obtained by using an optimal immersion plating method; finally, the rust-removed steel strip is galvanized based on the optimal preheating time and the optimal preheating temperature, and the galvanized rust-removed steel strip is cooled and passivated.

[0026] Through the description of the above implementation methods, the embodiments of the present invention can be provided as methods, systems or computer program products. Based on such an understanding, the above technical solutions can be essentially or partly contributed to the prior art in the form of software products, which can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and include several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0027] In the embodiments provided in the present application, it should be understood that the disclosed system or method can be implemented in other ways. The embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or units can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of systems, modules and units can be electrical, mechanical or other forms.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A continuous hot-dip galvanizing process for steel strip, characterized in that: The steps include: The galvanized steel strip is subjected to rust removal pretreatment, and the rust removal pretreatment steel strip is recorded as a rust removal steel strip; Performing heat pretreatment on the steel strip that can be tested, obtaining preheating parameters based on the duration of the heat pretreatment and the temperature of the heat pretreatment, and recording the steel strip after the preheat treatment as a pretreated steel strip; Immersing the pretreated steel strip in molten zinc solution, using an optimal immersion plating method to obtain an optimal preheating time and an optimal preheating temperature; The derusted steel strip is galvanized based on the preferred preheating time and the preferred preheating temperature, and the galvanized derusted steel strip is cooled and passivated.

2. A continuous hot-dip galvanizing process for steel strip according to claim 1, characterized in that: The galvanized steel strip is subjected to rust removal pretreatment, and the rust removal pretreatment steel strip is recorded as rust removal steel strip, including: The rust removal pretreatment is performed on the galvanized steel strip, and the rust removal pretreatment includes: immersing the galvanized steel strip in an alkaline electrolyte based on an electrolytic degreasing method, and passing direct current into the alkaline electrolyte until the electrolytic degreasing is completed; Use clean water to clean the electrolytically degreased steel strip. When the degreaser on the surface of the galvanized steel strip is completely removed, put the steel strip into a dilute hydrochloric acid solution for rust removal. When bubbles are generated on the surface of the steel strip to be galvanized in the dilute hydrochloric acid solution, the number of bubbles on the surface of the steel strip to be galvanized is obtained in real time, and when the number of bubbles in real time decreases, a corrosion inhibitor is added to the dilute hydrochloric acid solution until there are no bubbles on the surface of the steel strip to be galvanized; The steel strip that has been rust-removed is cleaned with clean water, and the moisture on the surface of the steel strip is dried. The steel strip at this time is recorded as a rust-removed steel strip.

3. A continuous hot-dip galvanizing process for steel strip according to claim 2, characterized in that: The steel strip capable of being tested is subjected to heat pretreatment, and the preheating parameters are obtained based on the duration of the heating pretreatment and the temperature of the heating pretreatment, including: The maximum temperature at which the steel strip can be heated is recorded as the maximum preheating temperature; a plane rectangular coordinate system is established and recorded as a preheating segmented coordinate system, wherein the unit of the X-axis of the preheating segmented coordinate system is time, and the unit of the Y-axis is temperature; the rust-removed steel strip is heated, and a corresponding curve is drawn in the preheating segmented coordinate system based on the heating time and the temperature of the surface of the rust-removed steel strip, which is recorded as a preheating temperature curve; The maximum number of steel strips that can be tested is recorded as k; the maximum value of the horizontal axis in the preheating temperature curve is recorded as X max , the maximum value of the ordinate in the preheating temperature curve is recorded as Y max .

4. A continuous hot-dip galvanizing process for steel strip according to claim 3, characterized in that: Performing heat pretreatment on the steel strip capable of being tested, and obtaining preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment further includes: Set the X axis from 0 to X max The interval is divided into k equal parts and recorded from left to right as horizontal interval HQ1 to horizontal interval HQ k ; For any horizontal interval HQ: record the point with the largest slope in the preheating temperature curve in the horizontal interval HQ as the horizontal fastest segmentation point; obtain the horizontal fastest segmentation point in each horizontal interval HQ; Set the Y axis from 0 to Y max The interval is divided into k parts, and recorded from bottom to top as vertical interval ZQ1 to vertical interval ZQ k ; For any longitudinal interval ZQ: record the point with the largest slope in the preheating temperature curve in the longitudinal interval ZQ as the longitudinal fastest dividing point; obtain the longitudinal fastest dividing point in each longitudinal interval ZQ.

5. A continuous hot-dip galvanizing process for steel strip according to claim 4, characterized in that: Performing heat pretreatment on the steel strip capable of being tested, and obtaining preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment further includes: Sequentially for horizontal intervals HQ1 to HQ k The fastest transverse segmentation points in are processed by mean elimination; the mean elimination process is as follows: obtain the fastest longitudinal segmentation point with the smallest difference in ordinate with the fastest transverse segmentation point, and record it as the mean elimination point of the fastest transverse segmentation point; record (X0, Y0) as the mean segmentation point, and eliminate the fastest transverse segmentation point and its corresponding mean elimination point from all the fastest transverse segmentation points and all the fastest longitudinal segmentation points, where X0 is the mean of the abscissa of the fastest transverse segmentation point and the abscissa of the mean elimination point of the fastest transverse segmentation point, and Y0 is the mean of the ordinate of the fastest transverse segmentation point and the ordinate of the mean elimination point of the fastest transverse segmentation point; Get all mean split points after mean elimination.

6. A continuous hot-dip galvanizing process for steel strip according to claim 5, characterized in that: Performing heat pretreatment on the steel strip capable of being tested, and obtaining preheating parameters based on the duration of the heating pretreatment and the temperature of the heating pretreatment further includes: Obtain k steel strips that can be tested, and record the horizontal coordinates and vertical coordinates corresponding to all mean split points as the preheating parameters of each steel strip; The steel strip is heated based on the preheating parameters of each steel strip, and the heated steel strip is recorded as a pretreated steel strip.

7. A continuous hot-dip galvanizing process for steel strip according to claim 6, characterized in that: The pretreated steel strip is immersed in molten zinc liquid, and the preferred preheating time and the preferred preheating temperature are obtained by the preferred immersion plating method, including: For any pretreated steel strip: immerse the pretreated steel strip in molten zinc liquid, and start timing after the pretreated steel strip is immersed in the molten zinc liquid. When zinc ash is generated on the surface of the zinc tank, the time point recorded at this time is recorded as the galvanizing reaction point; when the zinc ash on the surface of the zinc tank stops generating, the time point recorded at this time is recorded as the galvanizing end point, and the pretreated steel strip is taken out of the zinc liquid, and the coating thickness on the surface of the pretreated steel strip at this time is recorded as the zinc layer thickness, wherein the zinc tank is used to store molten zinc liquid; Obtain the galvanizing reaction point, galvanizing end point and zinc layer thickness corresponding to all pretreated steel strips.

8. A continuous hot-dip galvanizing process for steel strip according to claim 7, characterized in that: Preferred immersion plating methods include: For any pretreated steel strip, the value corresponding to the galvanizing end point of the pretreated steel strip minus the time corresponding to the galvanizing reaction point is recorded as the galvanizing time; the time corresponding to the galvanizing reaction point is recorded as the start time, and the value of the galvanizing time divided by the start time is recorded as the galvanizing reaction ratio; A plane rectangular coordinate system is established, which is recorded as the comprehensive screening coordinate system, wherein the X-axis and the Y-axis of the comprehensive screening coordinate system are both constant axes; an equilateral triangle is drawn with the coordinate origin as the center in the comprehensive screening coordinate system, which is recorded as the screening triangle; the three vertices of the screening triangle are recorded as the thickness vertex, the ratio vertex and the time vertex respectively; the standard range of the zinc layer thickness is obtained based on the galvanizing standard, and when the zinc layer thickness of the pretreated steel strip is within the standard range of the zinc layer thickness, the thickness parameter is set to 0; when the zinc layer thickness of the pretreated steel strip is outside the standard range of the zinc layer thickness, the thickness parameter is set to the minimum value of the difference between the zinc layer thickness and the standard range of the zinc layer thickness.

9. A continuous hot-dip galvanizing process for steel strip according to claim 8, characterized in that: Preferably, the immersion plating method further comprises: A ray is made from the coordinate origin as the endpoint in the direction of the thickness vertex, and the point whose length with the coordinate origin is the thickness parameter in the ray is recorded as the thickness screening point; a ray is made from the coordinate origin as the endpoint in the direction of the ratio vertex, and the point whose length with the coordinate origin is the galvanizing reaction ratio in the ray is recorded as the ratio screening point; a ray is made from the coordinate origin as the endpoint in the direction of the time vertex, and the point whose length with the coordinate origin is the total plating time in the ray is recorded as the time screening point, wherein the total plating time is the sum of the horizontal coordinate corresponding to the preheating parameter of the pretreated steel strip and the time corresponding to the galvanizing end point, and the unit of the total plating time is hour; The area of ​​the triangle formed by the thickness screening point, the ratio screening point and the time screening point is recorded as the screening parameter of the pretreated steel strip; The screening parameters of all pretreated steel strips are obtained, and the pretreated steel strip with the smallest screening parameters is recorded as the preferred treated steel strip; the horizontal coordinate and the vertical coordinate in the preheating parameters of the preferred treated steel strip are recorded as the preferred preheating time and the preferred preheating temperature, respectively.

10. A continuous hot-dip galvanizing process for steel strip according to claim 9, characterized in that: The rust-free steel strip is galvanized based on the preferred preheating time and the preferred preheating temperature, and the galvanized rust-free steel strip is cooled and passivated, including: Based on the preferred preheating time and the preferred preheating temperature, the rust-removed steel strip is preheated before being immersed in the molten zinc liquid; when the rust-removed steel strip is heated to the preferred preheating temperature at the preferred preheating time, the rust-removed steel strip is immersed in the molten zinc liquid until zinc ash on the surface of the zinc tank stops being generated, and the rust-removed steel strip is taken out from the zinc liquid; The rust-removed steel strip taken out from the zinc liquid is placed in cooling water for cooling treatment; The rust-removed steel strip taken out from the cooling water is immersed in the passivation liquid for passivation treatment.

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