A high quality 35W270 silicon steel sheet cold rolling process

Abstract

The present application relates to the field of silicon steel rolling technology, and specifically to a high-quality 35W270 silicon steel sheet cold rolling process, which includes: obtaining ultrasonic echo signals of non-oriented silicon steel; obtaining stress characteristic factors through the irregular characteristics of the ultrasonic echo signals of silicon steel sheets in the time domain and the energy difference characteristics in the frequency domain; obtaining the degree of stress concentration according to the stress concentration conditions in the areas with similar characteristics of the ultrasonic echo signals in the cold rolling section of the non-oriented silicon steel sheets, and obtaining the cold rolling speed adjustment factor through the trend characteristics of the degree of stress concentration; evaluating the trend of stress concentration changes in the non-oriented silicon steel sheets through the cold rolling speed adjustment factor, and adjusting the cold rolling speed of the silicon steel sheets based on this, and subjecting the cold-rolled silicon steel sheets to new energy silicon steel annealing coating to obtain 35W270 silicon steel sheets. The present application aims to analyze the stress concentration of non-oriented silicon steel sheets and provide scientific data support for optimizing the rolling speed of the cold rolling process of silicon steel sheets.

Description

Technical Field

[0001] The present application relates to the technical field of silicon steel rolling, and in particular to a high-quality 35W270 silicon steel plate cold rolling process. Background Art

[0002] 35W270 silicon steel plate is a high-performance non-oriented silicon steel sheet with high magnetic properties and low loss. It belongs to silicon steel laminates for high-end motors. Among them, 35W represents non-oriented new energy motor silicon steel with a thickness of 0.35mm, and 270 represents the standard value of iron loss of the silicon steel sheet is 2.7W / kg (low frequency 50Hz). With the future development trend of energy conservation and environmental protection, high magnetic properties and low loss silicon steel for motors has become the mainstream direction of industrial development. 35W270 silicon steel has the advantages of high saturation flux density, high magnetic induction intensity, low loss, excellent mechanical properties and fatigue resistance, etc., and is widely used in the field of drive motor magnetic conductive materials.

[0003] Due to the uneven chemical composition inside the silicon steel sheet or the uneven thickness of the silicon steel sheet caused by the previous process, the residual stress inside the silicon steel sheet will be high or concentrated, which makes the 35W270 silicon steel sheet easy to deform or even break during the cold rolling process, greatly affecting the magnetic conductivity and yield rate of the silicon steel sheet; however, the existing technology lacks accurate analysis of the increasing trend of stress concentration caused by the uneven chemical composition or inconsistent thickness of the silicon steel sheet, and it is difficult to determine whether the cold rolling speed needs to be adjusted. Summary of the invention

[0004] In view of the above, it is necessary to provide a high-quality 35W270 silicon steel sheet cold rolling process to solve the above problems.

[0005] An embodiment of the present application provides a high-quality 35W270 silicon steel sheet cold rolling process, the process comprising:

[0006] The silicon steel sheet after normalized pickling is cold rolled, and the specific process is as follows:

[0007] S1: Acquire ultrasonic echo signals of each cold rolling position in a preset cold rolling section of a silicon steel sheet to be cold rolled;

[0008] S2: For each cold rolling section, the peaks and troughs of the ultrasonic echo signal at each cold rolling position are extracted, and the signal irregularity of each cold rolling position is obtained according to the difference in the distribution of the peaks and troughs between each cold rolling position and all the cold rolling positions within its local range and the difference in the ultrasonic echo time interval; the energy difference of each cold rolling position is obtained by combining the difference between the corresponding energy of the fundamental frequency signal and the remaining frequency components of the ultrasonic echo signal at each cold rolling position in the frequency domain; the result of fusing the energy difference of each cold rolling position and the signal irregularity is used as the stress characteristic factor of each cold rolling position;

[0009] S3: clustering the stress characteristic factors of all cold rolling positions in each cold rolling section, and obtaining the stress concentration degree of each cluster based on the distribution characteristics of the stress characteristic factors in each cluster; and obtaining the cold rolling speed adjustment factor of each cold rolling section according to the distribution of the stress concentration degrees of all clusters in each cold rolling section;

[0010] S4: adjusting the cold rolling speed of the rolling mill based on the cold rolling speed adjustment factor of each cold rolling section;

[0011] Wherein, the rolling mill can be a six-roller small-roller diameter six-roller continuous rolling mill or a 20-roller rolling mill;

[0012] The silicon steel sheet after cold rolling is subjected to new energy silicon steel annealing coating to obtain 35W270 silicon steel sheet.

[0013] The signal irregularity degree of each cold rolling position is obtained as follows:

[0014] For each cold rolling section, all the peaks and troughs in the ultrasonic echo signal at each cold rolling position are combined into a peak sequence at each cold rolling position;

[0015] A local neighborhood is preset for each cold rolling position, and the distance measurement between each cold rolling position and the peak sequence of all cold rolling positions in its local neighborhood is fused to obtain a first difference; the difference between the ultrasonic echo time intervals of each cold rolling position and all cold rolling positions in its local neighborhood is fused to obtain a second difference; based on the first difference and the second difference, the signal irregularity degree of each cold rolling position is obtained, wherein the signal irregularity degree is positively correlated with the first difference and the second difference.

[0016] The specific process of obtaining the energy difference of each cold rolling position is as follows:

[0017] The difference between the corresponding energy of the fundamental frequency signal and the remaining frequency components of the ultrasonic echo signal of each cold rolling position in the frequency domain is recorded as the energy difference factor of each cold rolling position; the difference between the energy difference factors of each cold rolling position and all the cold rolling positions in its local neighborhood is fused as the energy difference of each cold rolling position.

[0018] The stress concentration degree of each cluster is obtained as follows:

[0019] Based on the difference in stress characteristic factors between the cluster center and the remaining cold rolling positions in each cluster, combined with the degree of disorder of all stress characteristic factors in the cluster, the stress aggregation degree of each cluster is obtained.

[0020] Wherein, obtaining the cold rolling speed adjustment factor of each cold rolling section includes:

[0021] The stress concentration degree of all clusters in each cold rolling section is arranged in the order of the distance between the cluster center and the rolling mill from far to near to form a stress concentration sequence for each cold rolling section;

[0022] The cold rolling speed adjustment factor in the pth cold rolling section is recorded as , the formula is: ;in, is the total number of clusters of non-oriented silicon steel sheets in the pth cold rolling section; is the difference between the xth data and the x+1th data in the stress concentration sequence of the pth cold rolling section; is the maximum distance between the cluster center of the pth cold rolling section cluster and the rolling mill; norm[] is the normalization function, and e is a natural constant.

[0023] Wherein, the adjusting of the cold rolling speed of the rolling mill comprises:

[0024] When the cold rolling speed adjustment factor is less than the preset adjustment threshold, there is no need to adjust the cold rolling speed of the rolling mill, and the cold rolling speed is 120m / min; otherwise, the cold rolling speed of the rolling mill is reduced by a preset amplitude.

[0025] The cold rolling parameters of the six-roller small-roller six-roller continuous rolling are as follows: the reduction rates of the No. 1 to No. 6 rolling mills are set to 37.8%, 33.6%, 31.6%, 30.8%, 28.9%, and 21.9% respectively; the roughness of the intermediate rolls of the rolling mill stand is The roughness of the working rolls of the 1st to 6th rolling mill stands are 、 , , , , .

[0026] The cold rolling parameters of the 20-roll mill are as follows: the roughness of the working rolls in passes 1-5 is , the roughness of the finished product is ; Surface roughness of the first middle, second middle and support rollers .

[0027] The emulsion spraying process of the six-roller small-roller six-roller continuous rolling mill is as follows: the spacing between the emulsion nozzles on each rolling mill is 60 mm, the emulsion is sprayed at a pressure of 0.7 MPa, the total emulsion flow rate is 50,000 L / min, and the emulsion temperature is 50-55 °C. 5℃, concentration in emulsion 3%~5% + high concentration in emulsion 10%.

[0028] The emulsion injection treatment process of the 20-roll mill is as follows: the total emulsion flow rate is 10,000 L / min, the emulsion temperature is 50-55°C ± 5°C, and the concentration in the emulsion is 3%-5%.

[0029] This application has at least the following beneficial effects:

[0030] The present application obtains the signal irregularity through the time domain characteristics of the ultrasonic echo signal of the silicon steel plate, constructs the stress characteristic factor in combination with the frequency domain energy difference characteristics, comprehensively analyzes the difference in ultrasonic echo signal characteristics caused by the uneven chemical composition inside the non-oriented silicon steel plate or the uneven thickness of the silicon steel plate, and more accurately reflects the stress distribution characteristics of each cold rolling position of the non-oriented silicon steel plate; obtains the stress concentration degree according to the stress concentration condition in the area with similar ultrasonic echo signal characteristics in the cold rolling section of the non-oriented silicon steel plate, obtains the cold rolling speed adjustment factor through the stress concentration degree change trend characteristics, and further analyzes the stress concentration degree change trend of the non-oriented silicon steel plate along the reverse direction of rolling on the basis of the division of the stress distribution characteristics of the non-oriented silicon steel plate, which more accurately reflects the stress concentration change of the non-oriented silicon steel plate. Based on this, the cold rolling speed of the silicon steel plate is adjusted, which can avoid the drawbacks that the stress concentration trend of the non-oriented silicon steel plate gradually increases and the cold rolling speed is too fast, resulting in excessive shear force on the silicon steel plate product, and the stress release is too fast, causing the silicon steel plate to deform or break, and provides scientific data support for optimizing the rolling speed of the cold rolling process of the silicon steel plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A flow chart of a high-quality 35W270 silicon steel sheet cold rolling process provided for this application;

[0032] Figure 2 Schematic diagram of the original ultrasonic echo signal of the silicon steel plate provided in this application and the ultrasonic echo signal after wavelet denoising;

[0033] Figure 3 A time domain waveform diagram of an ultrasonic echo signal at the mth cold rolling position in a cold rolling section of a silicon steel sheet provided in the present application;

[0034] Figure 4 A time domain waveform diagram of an ultrasonic echo signal at the nth cold rolling position in a cold rolling section of a silicon steel sheet provided in the present application;

[0035] Figure 5 This is a schematic diagram of the signal peaks and troughs obtained after the ultrasonic echo signal provided in this application is processed by the AMPD algorithm. DETAILED DESCRIPTION

[0036] In the description of the embodiments of the present application, words such as "exemplary", "or", "for example" and the like are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "or", "for example" and the like is intended to present related concepts in a concrete manner.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0038] It should also be noted that the terms "first" and "second" in this application and its drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. The method disclosed in the embodiments of the present application or the method shown in the flow chart includes one or more steps for implementing the method. Without departing from the scope of protection of this application, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0040] The present application embodiment proposes a high-quality 35W270 silicon steel plate cold rolling process, which is applied to the silicon steel rolling technology field. Figure 1 , the process comprises:

[0041] The silicon steel sheet after normalized pickling is cold rolled, and the specific process is as follows:

[0042] S1: Acquire ultrasonic echo signals of each cold rolling position in a preset cold rolling section of a silicon steel sheet to be cold rolled.

[0043] This application uses a SCADA (Supervisory Control and Data Acquisition) system to monitor and control the cold rolling process of non-oriented silicon steel 35W270 in real time. Place the 35W270 silicon steel sheet to be cold rolled after normalizing and pickling flat on the conveyor belt to ensure that the surface of the silicon steel sheet is clean and free of oil and water stains. Then apply an appropriate ultrasonic coupling agent on the surface of the silicon steel sheet. The purpose of using the ultrasonic coupling agent is to reduce the air gap between the ultrasonic probe and the silicon steel sheet sample and improve the transmission efficiency of the ultrasonic signal. Take the preset length as a cold rolling section. In this embodiment, the preset length is 60m, and the implementer can choose it according to the actual situation. Use an ultrasonic detector to obtain the ultrasonic echo signal at each cold rolling position of the silicon steel sheet. The specific acquisition method is as follows:

[0044] An ultrasonic probe is used to scan the 35W270 silicon steel sheet in the opposite direction of rolling direction (RD) at a vertical angle and in a surface scanning manner to obtain ultrasonic echo signals at each cold rolling position in any cold rolling section, and the interval between the time when the ultrasonic probe transmits the ultrasonic signal and the time when the ultrasonic probe receives the ultrasonic echo is taken as the ultrasonic echo time interval. In order to prevent the acquired ultrasonic echo signal from being seriously interfered by the external environmental noise, the wavelet transform method is used to denoise the acquired ultrasonic echo signal. Since the wavelet transform method is a well-known technology, the specific acquisition process will not be described in detail.

[0045] Among them, the schematic diagram of the original ultrasonic echo signal of the silicon steel plate and the ultrasonic echo signal after wavelet denoising is as follows: Figure 2 As shown, the ordinate is the amplitude of the ultrasonic echo signal in the time domain, and the abscissa is time.

[0046] S2: For each cold rolling section, the peaks and troughs of the ultrasonic echo signal at each cold rolling position are extracted, and the signal irregularity of each cold rolling position is obtained according to the difference in peak and trough distribution between each cold rolling position and all cold rolling positions within its local range and the difference in ultrasonic echo time interval; the energy difference of each cold rolling position is obtained by combining the difference between the corresponding energy of the fundamental frequency signal and the remaining frequency components of the ultrasonic echo signal at each cold rolling position in the frequency domain; the result of fusing the energy difference of each cold rolling position and the signal irregularity is used as the stress characteristic factor of each cold rolling position.

[0047] In silicon steel sheets after normalized pickling, the inhomogeneity of the internal chemical composition of the material may lead to differences in the thermal expansion coefficients at different cold rolling positions. Different stresses are generated during the cooling process of the silicon steel sheet. Specifically, in the ultrasonic echo signal of the silicon steel sheet, the inhomogeneity of the chemical composition makes the ultrasonic signal impedance of the material different, which in turn affects the propagation speed of the ultrasonic wave in the material; it also causes the amplitude of the reflected waveform corresponding to the ultrasonic echo signal at different cold rolling positions to be irregular.

[0048] Among them, the time domain waveform diagram of the ultrasonic echo signal at the mth and nth cold rolling positions in the cold rolling section of the silicon steel sheet is as follows: Figure 3 , 4 As shown in the figure, the vertical axis of the two figures is the amplitude of the ultrasonic echo signal in the time domain, and the horizontal axis is the time ( s), it can be seen that the ultrasonic echo signals at different positions have irregular amplitudes and amplitude differences due to the uneven chemical composition.

[0049] For each cold rolling section, all the peaks and troughs in the ultrasonic echo signal at each cold rolling position are combined into a peak sequence at each cold rolling position.

[0050] Specifically, in this embodiment, any cold rolling section is taken as an example for subsequent processing, and the ultrasonic echo signals at each cold rolling position are respectively used as input. The peak detection algorithm obtains all the peaks and troughs in the ultrasonic echo signal at each cold rolling position, and takes the sequence composed of all the peaks and troughs of the ultrasonic echo signal in time sequence as the peak sequence of the ultrasonic echo signal.

[0051] Among them, the schematic diagram of the signal peaks and troughs obtained after the ultrasonic echo signal is processed by the AMPD algorithm is as follows: Figure 5 shown.

[0052] A local neighborhood is preset for each cold rolling position, and the distance measurement between each cold rolling position and the peak sequence of all cold rolling positions in its local neighborhood is fused to obtain a first difference; the difference between the ultrasonic echo time intervals of each cold rolling position and all cold rolling positions in its local neighborhood is fused to obtain a second difference; based on the first difference and the second difference, the signal irregularity degree of each cold rolling position is obtained, wherein the signal irregularity degree is positively correlated with the first difference and the second difference.

[0053] It should be noted that a positive correlation means that as one variable increases, the other variable also increases; a negative correlation means that as one variable increases, the other variable decreases.

[0054] In the process of obtaining the signal irregularity of this embodiment, each cold rolling position is taken as the center and the size is The area is recorded as the local neighborhood of each cold rolling position; the distance measurement between sequences is measured by dynamic time warping (DTW); the difference between variables is measured by the calculation method of the absolute value of the difference, and multiple variables can be fused by addition and multiplication methods, that is, the first difference is specifically the cumulative sum of the DTW distances between each cold rolling position and the peak sequences of all cold rolling positions in its local neighborhood; the second difference is specifically the cumulative sum of the absolute values ​​of the differences between the ultrasonic echo time intervals of each cold rolling position and all cold rolling positions in its local neighborhood; the signal irregularity is specifically the product of the normalized value of the first difference and the normalized value of the second difference; wherein, the normalization method uses the sigmoid function for normalization.

[0055] It should be understood that when the difference in ultrasonic signal propagation caused by insufficient chemical composition inside the silicon steel plate is more significant, the reflected waveform of the ultrasonic echo signal is more irregular, the difference in ultrasonic echo time intervals is greater, and the degree of irregularity of the signal waveform at different cold rolling positions of the silicon steel plate is greater, that is, the distance measurement between the corresponding peak sequences at different cold rolling positions is greater, and the difference between the corresponding ultrasonic echo time intervals at different cold rolling positions is greater.

[0056] Under normal circumstances, in silicon steel sheets after normalizing and pickling, the thickness difference of silicon steel sheets may also lead to uneven stress distribution inside the material, which is specifically manifested in the ultrasonic echo signal of the silicon steel sheets: the greater the thickness difference at different cold-rolled positions of the silicon steel sheets, the more obvious the scattering phenomenon and energy attenuation of the ultrasonic signal in the material.

[0057] The difference between the corresponding energy of the fundamental frequency signal and the remaining frequency components of the ultrasonic echo signal of each cold rolling position in the frequency domain is recorded as the energy difference factor of each cold rolling position; the difference between the energy difference factors of each cold rolling position and all the cold rolling positions in its local neighborhood is fused as the energy difference of each cold rolling position.

[0058] In the process of acquiring the energy difference of this embodiment, the accumulated value of the difference between the fundamental frequency signal of the ultrasonic echo signal of each cold rolling position and the corresponding energy of the remaining frequency components in the frequency domain is used as the energy difference factor of each cold rolling position; the energy difference of each cold rolling position is specifically the accumulated sum of the absolute values ​​of the differences between the energy difference factors of each cold rolling position and each cold rolling position in its local neighborhood.

[0059] It should be understood that when the stress distribution difference of the silicon steel plate is more significant due to the uneven thickness, the scattering phenomenon and energy attenuation of the ultrasonic echo signal in the material at different cold rolling positions are more obviously different, and the signal difference is stronger, that is, the difference between the fundamental frequency signal of the ultrasonic echo signal at different cold rolling positions and the cumulative result of the energy difference corresponding to all other frequency components is greater.

[0060] When the internal stress distribution of the silicon steel plate is more significantly different due to uneven internal chemical composition or uneven thickness, the cold rolling speed parameters of the silicon steel plate should be adjusted in time to avoid the cold rolling speed being too fast, which may cause the deformation energy storage of the silicon steel plate to be released too quickly during the cold rolling process, resulting in cold rolling deformation or fracture of the silicon steel plate.

[0061] Based on this, the energy difference of each cold rolling position and the signal irregularity are fused as the stress characteristic factor of each cold rolling position.

[0062] In this embodiment, the normalized value of the product of the energy difference of each cold rolling position and the signal irregularity degree is used as the stress characteristic factor of each cold rolling position, wherein the normalization method adopts the sigmoid function.

[0063] It should be understood that when the stress distribution condition of the silicon steel sheet at any cold rolling position is more significantly different from that of the surrounding area due to uneven internal chemical composition or uneven thickness, the stress characteristics at the cold rolling position are more obvious, that is, the irregularity of the ultrasonic echo signal is stronger, and the energy attenuation difference of the ultrasonic echo signal is greater.

[0064] S3: Cluster the stress characteristic factors of all cold rolling positions in each cold rolling section, and obtain the stress concentration degree of each cluster based on the distribution characteristics of the stress characteristic factors in each cluster; according to the distribution of the stress concentration degree of all clusters in each cold rolling section, obtain the cold rolling speed adjustment factor of each cold rolling section.

[0065] The stress characteristic factor at each cold rolling position alone cannot reflect the stress concentration level inside the silicon steel sheet, and thus cannot provide scientific data support for the subsequent cold rolling speed adjustment. Generally, in the stress concentration area of ​​the silicon steel sheet to be cold rolled, the distribution of its internal chemical composition and the thickness consistency of the material are usually related.

[0066] The stress characteristic factors of all cold rolling positions in each cold rolling section are clustered. Based on the difference in stress characteristic factors between the cluster center and the remaining cold rolling positions in each cluster and the degree of disorder of all stress characteristic factors in the cluster, the stress aggregation degree of each cluster is obtained.

[0067] Based on the above analysis, the stress characteristic factors at all cold rolling positions in any cold rolling section are taken as input, and the K-mediods clustering algorithm is used to obtain all cluster clusters and cluster centers in the cold rolling section of the silicon steel plate. In this embodiment, the number of cluster centers is set to 10; it should be noted that the larger the number of cluster centers, the more detailed the division of stress distribution characteristics, but at the same time it will increase the risk of over-division of cluster clusters and increase the amount of calculation. The implementer can set the number of cluster centers according to the actual situation; the absolute value of the difference between the stress characteristic factors of any two cold rolling positions is taken as the metric distance between the silicon steel plate areas corresponding to the any two cold rolling positions. Since the K-mediods clustering algorithm is a well-known technology, the specific acquisition process will not be described in detail.

[0068] In the calculation of the degree of stress concentration in this embodiment, the absolute value of the difference is used to measure the difference between the stress characteristic factors, and the Shannon entropy is used to measure the degree of disorder of the stress characteristic factors in each cluster. That is, the degree of stress concentration is specifically: for each cluster, the absolute value of the difference between the stress characteristic factors of the cluster center and all other cold rolling positions is summed, and the sum is multiplied by the Shannon entropy of all stress characteristic factors in the cluster, and the inverse is obtained to obtain the degree of stress concentration of each cluster.

[0069] It should be understood that when the degree of internal stress concentration of the silicon steel sheet in the cold rolling section is more significant, the consistency of the ultrasonic echo signal characteristics at each cold rolling position within the region is stronger, the difference between the regional stress characteristics of the silicon steel sheet at each cold rolling position within the cluster and the cluster center is more blurred, and the regional stress characteristics of the silicon steel sheet at each cold rolling position within the cluster are more stable, that is, the degree of confusion of the corresponding stress characteristic factors at all cold rolling positions within the cluster is smaller, and the difference between the corresponding stress characteristic factors at the cluster center and all other cold rolling positions in the cluster is smaller.

[0070] For the non-oriented silicon steel sheet after normalized pickling, the stronger the stress concentration trend is along the opposite direction of the silicon steel sheet RD, the more serious the stress concentration of the non-oriented silicon steel sheet is. In the subsequent cold rolling process, the cold rolling speed should be optimized to avoid excessive shear force of the silicon steel sheet caused by too fast cold rolling speed. The rapid release of stress causes deformation and fracture of the silicon steel sheet during the cold rolling process, affecting the performance and yield rate of the silicon steel sheet.

[0071] Therefore, the stress concentration degrees of all clusters in the cold rolling section of non-oriented silicon steel sheets are arranged in the order of the distance between the cluster center and the rolling mill from far to near to form a stress concentration sequence of non-oriented silicon steel sheets in the cold rolling section.

[0072] According to the distribution of stress concentration sequence elements in each cold rolling section, the cold rolling speed adjustment factor of each cold rolling section is obtained, and its formula is as follows: ;in, is the cold rolling speed adjustment factor of the non-oriented silicon steel sheet in the pth cold rolling section; is the total number of clusters of non-oriented silicon steel sheets in the pth cold rolling section; is the difference between the xth data and the x+1th data in the stress concentration sequence corresponding to the pth cold rolling section; is the maximum distance between the cluster center of the pth cold rolling section cluster and the rolling mill; norm[] is the normalization function, so that The value range of is between [0,1], and e is a natural constant.

[0073] It should be understood that when the internal stress concentration trend of the non-oriented silicon steel sheet in the reverse direction of RD is more significant, it means that the internal stress concentration degree of the non-oriented silicon steel sheet in the subsequent cold rolling process becomes more obvious, and the distance interval between the stress concentration areas becomes smaller, that is, the cumulative result of the difference between the stress concentration degree of all data in the stress concentration sequence corresponding to the cold rolling section and the corresponding stress concentration degree of the previous data is larger, and the cumulative result of the difference in the horizontal coordinate distance between each cluster in the reverse direction of RD of the non-oriented silicon steel sheet and the corresponding cluster center of the previous cluster in the cold rolling section is smaller. At this time, the cold rolling speed of the non-oriented silicon steel sheet in the subsequent cold rolling process should be adjusted in time to avoid excessive shear force on the silicon steel sheet product due to the gradually increasing stress concentration trend of the silicon steel sheet and the excessively fast cold rolling speed, which may cause deformation or fracture due to excessive stress release, affecting the performance and yield rate of the silicon steel sheet.

[0074] S4: adjusting the cold rolling speed of the rolling mill based on the cold rolling speed adjustment factor of each cold rolling section.

[0075] An adjustment threshold T is set, and the cold rolling speed adjustment factor of each cold rolling section is obtained through the data statistical analysis module in the SCADA system. In this application, the preset thickness of the non-oriented silicon steel sheet after cold rolling is 0.35 mm, and the non-oriented silicon steel sheet is cold rolled using a six-roll continuous rolling mill or a 20-roll Sendkimier rolling mill.

[0076] (1) When the cold rolling speed adjustment factor corresponding to the cold rolling section of the non-oriented silicon steel sheet is less than the adjustment threshold T, the trend of increasing stress concentration due to uneven internal chemical composition or inconsistent thickness in the cold rolling section corresponding to the non-oriented silicon steel sheet is not obvious, and there is no need to adjust the cold rolling speed. The specific cold rolling parameters of the non-oriented silicon steel sheet are:

[0077] Example 1 uses six-roller small-roller six-roller continuous rolling for cold rolling:

[0078] The reduction rates of rolling mills No. 1 to No. 6 are set to 37.8%, 33.6%, 31.6%, 30.8%, 28.9%, and 21.9% respectively; the roughness of the intermediate rolls of the rolling mill stands is , 1 The roughness of the working rolls of the No. 6 rolling mill stand is 、 , , , , 。

[0079] The cold rolling speed of non-oriented silicon steel products is set at 120m / min;

[0080] The emulsion spraying treatment process of the six-roller small-roller diameter six-roller continuous rolling mill is as follows: the emulsion nozzles DT and DB on each rolling mill directly spray lubricate the steel strip and working rolls, the spacing between each nozzle is 60mm, the emulsion is sprayed at a pressure of 0.7Mpa, the total emulsion flow rate is 50000L / min, and the emulsion temperature is 50~55℃ 5℃, concentration in emulsion 3%~5% + high concentration in emulsion 10%.

[0081] Example 2: Cold rolling treatment was performed using a 20-roller Sendkimier mill:

[0082] The basic parameters for setting the emulsion system of the 20-roller Sendkimer mill are: 1-5 pass working roll roughness: , finished product pass roughness ; Surface roughness of the first middle, second middle and support rollers .

[0083] The cold rolling speed of non-oriented silicon steel products is set at 120m / min;

[0084] The emulsion injection treatment process of the 20-roll mill is set as follows: total emulsion flow rate: 10000L / min, emulsion temperature: 50-55℃±5℃, and emulsion concentration 3%~5%.

[0085] (2) When the cold rolling speed adjustment factor is greater than or equal to the cold rolling speed adjustment threshold T, the stress concentration degree in the corresponding cold rolling section due to the uneven internal chemical composition or inconsistent thickness is more obvious, and the cold rolling speed of the non-oriented silicon steel sheet needs to be adjusted. The specific cold rolling parameters are:

[0086] During the cold rolling process of non-oriented silicon steel sheets, the reduction rate of each rolling mill, the roughness of the frame working rolls and the related parameters of the emulsion injection treatment remain unchanged, and the cold rolling speed is reduced to Um / min. The purpose of reducing the cold rolling speed of the non-oriented silicon steel sheets is to reduce the shear force on the non-oriented silicon steel sheets during the cold rolling process, and at the same time slow down the release rate of the internal stress of the non-oriented silicon steel sheets, so as to avoid the internal stress of the silicon steel sheets being released too quickly, resulting in deformation and fracture of the silicon steel sheets during the cold rolling process.

[0087] In the present application, the cold rolling speed adjustment threshold T is taken as 0.6, and the cold rolling speed adjustment parameter U is 20. The larger the cold rolling speed adjustment threshold is, the stricter the cold rolling process requirements for non-oriented silicon steel products are. The implementer can set the cold rolling speed adjustment threshold and the cold rolling speed adjustment parameter value according to the actual situation.

[0088] Finally, the cold-rolled silicon steel sheet is subjected to new energy silicon steel annealing coating to obtain a 35W270 silicon steel sheet.

[0089] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0090] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. 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. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A high-quality 35W270 silicon steel sheet cold rolling process, characterized in that: The process includes: The silicon steel sheet after normalized pickling is cold rolled, and the specific process is as follows: S1: Acquire ultrasonic echo signals of each cold rolling position in a preset cold rolling section of a silicon steel sheet to be cold rolled; S2: For each cold rolling section, the peaks and troughs of the ultrasonic echo signal at each cold rolling position are extracted, and the signal irregularity of each cold rolling position is obtained according to the difference in the distribution of the peaks and troughs between each cold rolling position and all the cold rolling positions within its local range and the difference in the ultrasonic echo time interval; the energy difference of each cold rolling position is obtained by combining the difference between the corresponding energy of the fundamental frequency signal and the remaining frequency components of the ultrasonic echo signal at each cold rolling position in the frequency domain; the result of fusing the energy difference of each cold rolling position and the signal irregularity is used as the stress characteristic factor of each cold rolling position; S3: clustering the stress characteristic factors of all cold rolling positions in each cold rolling section, and obtaining the stress concentration degree of each cluster based on the distribution characteristics of the stress characteristic factors in each cluster; and obtaining the cold rolling speed adjustment factor of each cold rolling section according to the distribution of the stress concentration degrees of all clusters in each cold rolling section; S4: adjusting the cold rolling speed of the rolling mill based on the cold rolling speed adjustment factor of each cold rolling section; Wherein, the rolling mill is a six-roller small-roller-diameter six-roller continuous rolling mill or a 20-roller rolling mill; The cold-rolled silicon steel sheet is subjected to new energy silicon steel annealing coating to obtain a 35W270 silicon steel sheet; The step of obtaining the cold rolling speed adjustment factor of each cold rolling section includes: The stress concentration degree of all clusters in each cold rolling section is arranged in the order of the distance between the cluster center and the rolling mill from far to near to form a stress concentration sequence for each cold rolling section; The cold rolling speed adjustment factor in the pth cold rolling section is recorded as , the formula is: ;in, is the total number of clusters of non-oriented silicon steel sheets in the pth cold rolling section; is the difference between the xth data and the x+1th data in the stress concentration sequence of the pth cold rolling section; is the maximum distance between the cluster center of the pth cold rolling section cluster and the rolling mill; norm[] is the normalization function, and e is a natural constant.

2. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The signal irregularity degree of each cold rolling position is obtained as follows: For each cold rolling section, all the peaks and troughs in the ultrasonic echo signal at each cold rolling position are combined into a peak sequence at each cold rolling position; A local neighborhood is preset for each cold rolling position, and the distance measurement between each cold rolling position and the peak sequence of all cold rolling positions in its local neighborhood is fused to obtain a first difference; the difference between the ultrasonic echo time intervals of each cold rolling position and all cold rolling positions in its local neighborhood is fused to obtain a second difference; based on the first difference and the second difference, the signal irregularity degree of each cold rolling position is obtained, wherein the signal irregularity degree is positively correlated with the first difference and the second difference.

3. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The specific process of obtaining the energy difference of each cold rolling position is: The difference between the corresponding energy of the fundamental frequency signal and the remaining frequency components of the ultrasonic echo signal of each cold rolling position in the frequency domain is recorded as the energy difference factor of each cold rolling position; the difference between the energy difference factors of each cold rolling position and all the cold rolling positions in its local neighborhood is fused as the energy difference of each cold rolling position.

4. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The stress concentration degree of each cluster is obtained as follows: Based on the difference in stress characteristic factors between the cluster center and the remaining cold rolling positions in each cluster, combined with the degree of disorder of all stress characteristic factors in the cluster, the stress aggregation degree of each cluster is obtained.

5. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The step of adjusting the cold rolling speed of the rolling mill comprises: When the cold rolling speed adjustment factor is less than the preset adjustment threshold, there is no need to adjust the cold rolling speed of the rolling mill, and the cold rolling speed is 120m / min; otherwise, the cold rolling speed of the rolling mill is reduced by a preset amplitude.

6. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The cold rolling parameters of the six-roller small-roller six-roller continuous rolling are: the reduction rates of the No. 1 to No. 6 rolling mills are set to 37.8%, 33.6%, 31.6%, 30.8%, 28.9%, and 21.9% respectively; the roughness of the middle roll of the rolling mill stand is The roughness of the working rolls of the 1st to 6th rolling mill stands are 、 , , , , .

7. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The cold rolling parameters of the 20-roll mill are: the roughness of the working rolls in the 1st to 5th passes is , the roughness of the finished product is ; Surface roughness of the first middle, second middle and support rollers .

8. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The emulsion spraying process of the six-roller small-roller six-roller continuous rolling mill is as follows: the spacing between the emulsion nozzles on each rolling mill is 60 mm, the emulsion is sprayed at a pressure of 0.7 MPa, the total emulsion flow rate is 50,000 L / min, and the emulsion temperature is 50-55°C. 5℃, concentration in emulsion 3%~5% + high concentration in emulsion 10%.

9. A high-quality 35W270 silicon steel sheet cold rolling process as claimed in claim 1, characterized in that: The emulsion injection treatment process of the 20-roll mill is as follows: the total emulsion flow rate is 10000 L / min, the emulsion temperature is 50-55°C ± 5°C, and the concentration in the emulsion is 3%-5%.

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