Feedforward gauge control method for continuous hot rolling mill based on work roll vibration test analysis

Abstract

To provide a feed-forward plate thickness control method for a hot continuous mill, which can improve performance of plate thickness control under a vibration condition of a rolling work roll and improving accuracy of plate thickness control of a band plate.SOLUTION: The feed-forward plate thickness control method for the hot continuous mill based on work roll vibration test analysis acquires vibration acceleration data by an acceleration sensor disposed in a rolling work roll, acquires vibration displacement data of the rolling work roll in a rolling step through noise reduction and integration of a primitive signal, acquires a fluctuation value of a plate thickness of a band plate at a mill exit when the mill vibrates on the basis of a relationship between the vibration displacement of the work roll and the plate thickness of the band plate at the mill exit, calculates a roll gap adjustment amount, and executes plate thickness control.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the technical field of automatic thickness control of a metal strip rolling mill, and in particular to a feedforward thickness control method for a continuous hot rolling mill based on work roll vibration test analysis. [Background technology]

[0002] With the development of industries such as aerospace, defense, shipping, automobiles, and bridge construction, the precision of thickness of metal strip is one of the most important quality indicators for strip products, and the requirements for its precision are becoming more stringent in downstream production.

[0003] Generally, the automatic thickness control system of a hot continuous rolling mill includes three thickness control methods, namely, feedforward automatic gain control (AGC), pressure AGC, and monitor AGC, as well as other compensation methods. Among them, the normal feedforward AGC control method of a hot continuous rolling mill unit is mainly the plasticity coefficient feedforward AGC, which is measured according to the hardness distribution at the entrance stand of the strip, and adjusts the roll gap of the downstream stand to correct the thickness deviation caused by the hardness change of the supplied material, thereby improving the accuracy of the overall thickness control.

[0004] However, the feedforward AGC has its own defects, and the control effect depends on the calculation accuracy of the strip plasticity coefficient, so it cannot directly reflect the thickness variation of the strip steel at the outlet of the upstream stand, and it cannot adjust the roll gap at the downstream stand. As the rolling specifications of strip become thinner and thinner, and the strength of strip becomes higher, serious vibration problems occur in the strip rolling mill, which greatly affect the thickness accuracy of the strip. Therefore, in the existing feedforward thickness AGC control method of the hot continuous rolling mill unit, the strip thickness at the inlet of each stand cannot meet the preset thickness standard of the rolling process, and the thickness accuracy of the product does not meet the requirements, and even the steel strip is broken or piled up during the production process, which causes production accidents that endanger the safety of equipment and personnel.

[0005] In the prior art, process information may be measured online using measuring devices such as an inlet thickness gauge and an inlet rolling speed sensor, but this method does not allow the installed equipment to measure the thickness variation of the strip between stands. In addition, a thickness gauge may be installed between each stand to measure the thickness variation of the strip between stands, but the thickness variation measured by this method has a time delay and cannot timely and accurately reflect the thickness variation when the rolling work roll vibrates, so that the downstream stand cannot timely adjust the thickness variation, which causes thickness defects in the strip product. In addition, the thickness gauge is expensive and difficult to maintain, which brings high usage and maintenance costs to manufacturers. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the technical problem that it is not possible to control the thickness fluctuation of rolled strip steel in a continuous hot rolling mill unit at low cost in the conventional technology, and has an object to provide a feedforward plate thickness control method for a continuous hot rolling mill based on work roll vibration test analysis. [Means for solving the problem]

[0007] The technical means of the present invention are as follows:

[0008] A method for feedforward plate thickness control of a hot continuous rolling mill based on a work roll vibration test analysis according to one aspect of the present invention includes the following steps: Acquiring an original vibration acceleration signal of the rolling work roll in a rolling process by an acceleration sensor disposed on a bearing stand of the rolling work roll; performing noise reduction processing on the original vibration acceleration signal of the rolling work roll to obtain a noise-reduced vibration acceleration signal of the rolling work roll; Obtaining a vibration displacement signal of the rolling work roll by numerical integration; Obtaining a fluctuation signal of the thickness of the strip at the exit of the rolling mill based on a relationship between the vibration displacement signal of the rolling work roll and the thickness of the strip at the exit of the rolling mill; The method includes calculating a roll gap adjustment amount for the next stand based on fluctuation data of the thickness of the strip at the strip outlet of the previous stand, and adjusting the roll gap using a rolling mill reduction control system based on the calculated roll gap adjustment amount, thereby controlling the strip thickness.

[0009] Furthermore, acquiring a vibration acceleration signal of the rolling work roll during the rolling process includes attaching an acceleration sensor with a magnetic base vertically to a bearing stand of the rolling work roll before the rolling process is started, and acquiring an original vertical vibration acceleration signal of the rolling work roll when the rolling process is started.

[0010] Furthermore, performing noise reduction processing on the vibration acceleration signal of the rolling work roll and obtaining the vibration acceleration signal after noise reduction of the rolling work roll includes performing noise reduction processing on the vibration acceleration signal of the rolling work roll using a wavelet analysis method. The original vibration acceleration signal of the rolling work roll is subjected to wavelet transformation, that is, a wavelet base is selected to determine a wavelet decomposition layer N, and the signal is subjected to N-layer wavelet decomposition; The high frequency wavelet coefficients are subjected to threshold processing, and one appropriate threshold is reserved. If the wavelet coefficient is greater than the threshold, it is determined that it is controlled by the vibration acceleration signal of the rolling work roll, and if it is less than the threshold, it is determined that it is controlled by noise. The low frequency wavelet coefficients are reserved, and noise reduction processing is performed for each of the high frequency coefficients of the first to Nth layers using a hard threshold method; An inverse transformation is performed to reconstruct the vibration acceleration signal of the actual rolling work roll, that is, the low-frequency coefficients obtained by wavelet decomposition and the high-frequency coefficients of the first to Nth layers after threshold noise reduction processing are inverse wavelet transformed and reconstructed to obtain the vibration acceleration signal of the actual rolling work roll after noise reduction.

[0011] Furthermore, obtaining a vibration displacement signal of the rolling work roll using a second-order integral technique includes the steps of: Using the trapezoidal integration method, the actual vibration acceleration signal of the rolling work roll after noise reduction is subjected to first-order integration processing according to the following formula to obtain the vibration velocity signal of the rolling work roll:

number

number

[0012] Furthermore, acquiring fluctuation data of the thickness of the strip at the exit of the rolling mill based on the relationship between the vibration displacement signal of the rolling work roll and the thickness of the strip at the exit of the rolling mill includes the following steps: According to the rebound equation of the rolling mill, the thickness value of the strip at the exit of the rolling mill in the rolling process is calculated according to the following formula: h=S p +s(t) Here, h is the thickness value of the strip at the exit of the rolling mill in the rolling process, and S p is the roll gap value when the rolling mill is loaded, s(t) is the vibration displacement of the rolling work roll, The roll gap of the rolling mill under load is calculated by the following formula: S p=S′+P / C′ where S′ is the roll gap of the rolling mill when no load is applied, P is the preset rolling force of the rolling mill, and C′ is the total stiffness of the base of the rolling mill. Based on the set value of the strip thickness at the exit of the rolling mill and the strip thickness value in the actual rolling operation, the fluctuation amount of the strip thickness in the actual rolling process is calculated according to the following formula: Δh=h 0 -h Here, Δh is the amount of variation in the thickness of the strip in the actual rolling process, and h 0 is the set thickness value of the strip at the exit of the rolling mill, and h is the thickness value of the strip in actual rolling operation.

[0013] Further, the method of calculating the roll gap adjustment amount of the next stand based on the fluctuation signal of the strip thickness at the strip outlet of the previous stand, and adjusting the roll gap by the rolling control system of the rolling mill according to the calculated roll gap adjustment amount to control the strip thickness includes the following steps: Based on the amount of fluctuation in the thickness of the strip during the actual rolling operation of the rolling mill, the roll gap adjustment amount is calculated according to the following formula: ΔS=Δh Q / C′ Here, ΔS is the roll gap adjustment amount, Δh is the fluctuation value of the strip thickness, Q is the plasticity coefficient of the strip, and C′ is the total rigidity of the base of the rolling mill. According to the distance between the roll gaps of the rolling mills of the continuous rolling mill unit and the moving speed of the strip, calculate the time delay amount of the roll gap adjustment by the rolling mill control system according to the following formula: Δt=L / V where Δt is the time delay of the roll gap adjustment by the rolling mill, L is the distance between the roll gaps of the rolling mills of the continuous rolling mill unit, and V is the motion speed of the strip between the stands; After a time delay of Δt, the roll gap adjustment is performed by the rolling mill reduction system. Effect of the Invention

[0014] The present invention has the following advantages over the prior art.

[0015] In the present invention, the method of work roll vibration test analysis is used to calculate the thickness fluctuation value of the strip at the exit of the previous stand in actual rolling operation, and the calculated value is used to calculate the feedforward AGC in the next stand. By using such a feedforward thickness control method for a hot continuous rolling mill based on the work roll vibration test analysis, the numerical value of the thickness fluctuation of the strip between each stand when the rolling work roll vibrates is obtained, and this numerical value is used in the control process of the feedforward AGC. Therefore, the present invention can largely eliminate the influence of the thickness fluctuation of the strip when the rolling mill vibrates on the thickness deviation of the product strip, and ensure the quality of the strip product without adding any equipment, and is of positive significance in improving the product thickness accuracy in the longitudinal direction of the full-wrap strip and ensuring rolling stability. [Brief description of the drawings]

[0016] In order to more clearly describe the technical means of the embodiments of the present invention or the prior art, the drawings in the description of the embodiments or the prior art will be briefly described below. The following drawings relate to the embodiments of the present invention, and it is obvious that those skilled in the art can derive other drawings based on these drawings without creative labor.

[0017] [Figure 1] 1 is a flowchart of a feedforward thickness control method for a hot continuous rolling mill based on a work roll vibration test analysis in an embodiment of the present invention. [Diagram 2] FIG. 4 is a schematic diagram showing an original vibration acceleration signal of a rolling work roll before noise reduction in an embodiment of the present invention. [Diagram 3] FIG. 4 is a schematic diagram showing an actual vibration acceleration signal of a rolling work roll after noise reduction in an embodiment of the present invention. [Figure 4] FIG. 4 is a diagram showing a vibration displacement signal of a rolling work roll in an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In order to make the technical means of the present invention clearer, the technical means in the embodiments of the present invention will be described clearly and completely below with reference to the drawings in the embodiments of the present invention, and it goes without saying that the described embodiments are not all the embodiments but only some of the embodiments of the present invention. Any other embodiments that a person skilled in the art can obtain based on the embodiments of the present invention without any creative effort shall be included in the scope of protection of the present invention.

[0019] In addition, the terms "first", "second", and the like in the present specification and claims, and in the drawings described above, are intended to distinguish between similar objects, and are not intended to describe a particular order or priority. It should be understood that the data so used can be interchanged with one another under appropriate circumstances, so that the embodiments of the present invention described herein can be practiced in orders other than those shown or described herein. Furthermore, the terms "comprise" and "have" and variations thereof are intended to cover non-exclusive inclusions, e.g., a process, method, system, product, or apparatus that includes a series of steps or units need not be limited to the steps or units expressly described, but may include other steps or units not expressly described or inherent to other processes, methods, products, or apparatus.

[0020] As shown in FIG. 1, the present invention provides a feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis, which includes the following steps:

[0021] Step 1: An acceleration sensor is disposed on the bearing stand of the rolling work roll, and the acceleration sensor is used to obtain the original vibration acceleration signal of the rolling work roll during the rolling process.

[0022] Specifically, a uniaxial acceleration sensor with a magnetic base is attached to the vertical position of the bearing stand of the rolling work roll before the rolling process starts. When the rolling process starts, the acceleration sensor and the vibration signal acquisition unit acquire the original vibration acceleration signal A(t) of the rolling work roll. The acceleration sensor is an ICP uniaxial acceleration sensor with a sensitivity of 250. The sampling frequency of the vibration signal acquisition unit is 1000 Hz. The original vibration acceleration signal is shown in Figure 2.

[0023] Step 2: The original vibration acceleration signal of the rolling work roll is subjected to noise reduction processing, and the actual vibration acceleration signal a(t) after noise reduction of the rolling work roll is obtained.

[0024] Step 2 specifically includes the following steps:

[0025] Step 2.1: Use wavelet analysis method to perform wavelet decomposition of the original vibration acceleration signal of the rolling work roll, select the “db4” wavelet basis, and the decomposition layer is 5 layers, that is, the original vibration acceleration signal is subjected to 5-layer wavelet decomposition.

[0026] Step 2.2: Threshold the wavelet coefficients of the high frequency part, and select the threshold as 0.3 according to the following formula:

number

number

[0027] If the wavelet coefficient is larger than the threshold, it is determined that it is controlled by the vibration acceleration signal of the rolling work roll, and if it is smaller than the threshold, it is determined that it is controlled by noise.The low-frequency wavelet coefficients are reserved, and noise reduction processing is performed for each of the high-frequency coefficients of the first to fifth layers using the hard threshold method.

[0028] Step 2.3: Perform inverse transformation and reconstruct the actual vibration acceleration signal of the rolling work roll, that is, the low-frequency coefficients obtained by wavelet decomposition and the high-frequency coefficients of the first to fifth layers after the noise reduction process of the hard threshold are inverse wavelet transformed and reconstructed to obtain the actual vibration acceleration signal of the rolling work roll after noise reduction. The actual acceleration signal is shown in Figure 3.

[0029] Step 3: Using the integral method, obtain the vibration displacement data of the rolling work roll.

[0030] Step 3 specifically includes the following steps:

[0031] Step 3.1: The actual rolling work roll vibration acceleration signal after noise reduction is subjected to first-order integration processing using the trapezoidal integration method, and the vibration velocity signal of the rolling work roll is obtained, as shown in Figure 4, and the calculation formula is as follows:

number

[0032] Step 3.2: Using the trapezoidal integral method, the vibration velocity signal of the rolling work roll is subjected to first-order integral processing to obtain the rolling work roll vibration displacement signal, and the calculation formula is as follows:

number

[0033] Step 4: Based on the relationship between the vibration displacement data of the rolling work rolls and the thickness of the strip at the exit of the rolling mill, thickness fluctuation data of the strip at the exit of the rolling mill is obtained.

[0034] Step 4 specifically includes the following steps:

[0035] Step 4.1: According to the rolling mill bounce equation, the thickness value of the strip when the rolling work roll vibrates is obtained, and the calculation formula is as follows: h=S p +x(t) Here, h is the thickness value of the strip in the actual rolling operation, and S p is the roll gap value when the rolling mill is under load, and x(t) is the vibration displacement of the rolling work roll.

[0036] Among them, the roll gap S of the rolling mill under load p is calculated according to the following formula: S p =S′+P / C′ where S' is the roll gap of the rolling mill when no load is applied, P is the preset rolling force of the rolling mill, and C' is the total stiffness of the base of the rolling mill.

[0037] Step 4.2: The strip thickness setting value h set by the rolling mill control system 0 Based on the thickness h in the actual rolling operation obtained in step 4.1, the fluctuation value Δh of the thickness of the strip in the actual rolling operation is calculated, and the calculation formula is as follows: Δh=h 0 -h Here, Δh is the amount of variation in the thickness of the strip during actual rolling operation, and h 0is the set thickness value of the strip at the exit of the rolling mill, and h is the thickness value of the strip in actual rolling operation.

[0038] Step 5: Based on the fluctuation data of the strip thickness at the strip outlet of the previous stand, the roll gap adjustment amount for the next stand is calculated, and the roll gap is adjusted by the rolling mill's reduction control system in accordance with the calculated roll gap adjustment amount, thereby controlling the strip thickness.

[0039] Step 5 specifically includes the following steps:

[0040] Step 5.1: Based on the variation in strip thickness during the actual operation of the rolling mill, calculate the roll gap adjustment amount according to the following formula: ΔS=Δh Q / C′ Here, ΔS is the roll gap adjustment amount, Δh is the amount of variation in the strip thickness, Q is the plasticity coefficient of the strip, and C′ is the total rigidity of the base of the rolling mill.

[0041] Step 5.2: According to the distance between the roll gaps of the rolling mill units and the moving speed of the strip, calculate the time delay amount of the roll gap adjustment by the rolling mill control system according to the following formula: Δt=L / V where Δt is the time delay of the roll gap adjustment by the rolling mill, L is the distance between the roll gaps of the rolling mill units, and V is the motion speed of the strip between the stands.

[0042] Step 5.3: After a time delay of Δt, the roll gap adjustment is performed by the rolling mill reduction system to remove the thickness difference.

[0043] In the above embodiment, the method of work roll vibration test analysis is used to calculate the thickness fluctuation value of the strip at the exit of the previous stand during actual rolling operation, and the calculated fluctuation value is used to calculate the feedforward AGC for the next stand. By using such a feedforward thickness control method for a hot continuous rolling mill based on the work roll vibration test analysis, the thickness fluctuation value of the strip between each stand when the rolling work rolls vibrate is obtained, and the fluctuation value is used in the control process of the feedforward AGC, so that the present invention can largely eliminate the influence of the thickness fluctuation when the rolling mill vibrates on the thickness deviation of the product strip, and ensure the quality of the strip product without adding any equipment, and is of positive significance in improving the product thickness accuracy in the longitudinal direction of the full-wrap strip and ensuring rolling stability.

[0044] Finally, it should be noted that the above embodiments are merely illustrative of the technical means of the present invention, and are not intended to limit the technical means. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art will understand that the technical means described in the above embodiments may be modified or some or all of the technical features therein may be equivalently replaced, and even if such modifications or replacements are made, the essence of the corresponding technical means will not depart from the scope of the technical means in the embodiments of the present invention.

[0045] (Additional Note) (Appendix 1) Acquiring an original vibration acceleration signal of the rolling work roll in a rolling process by an acceleration sensor disposed on a bearing stand of the rolling work roll; performing noise reduction processing on the original vibration acceleration signal of the rolling work roll to obtain a noise-reduced vibration acceleration signal of the rolling work roll; Numerical integration of the noise-reduced vibration acceleration signal to obtain a vibration displacement signal of the rolling work roll; Obtaining fluctuation data of the thickness of the strip at the exit of the rolling mill based on a relationship between the vibration displacement signal of the rolling work roll and the thickness of the strip at the exit of the rolling mill; a roll gap adjustment amount for a next stand based on fluctuation data of the thickness of the strip at an exit of the rolling mill of a previous stand, and a roll gap adjustment by a reduction control system of the rolling mill in accordance with the calculated roll gap adjustment amount, thereby controlling the thickness.

[0046] (Appendix 2) Obtaining the original vibration acceleration signal of the rolling work roll in the rolling process includes: 2. A feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis according to claim 1, comprising attaching an acceleration sensor with a magnetic base in a vertical direction to the rolling work roll before the rolling process is started, and collecting an original vertical vibration acceleration signal of the rolling work roll using the acceleration sensor when the rolling process is started.

[0047] (Appendix 3) The feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis described in Appendix 1, characterized in that the acceleration sensor is an ICP uniaxial acceleration sensor and has a sensitivity of 250.

[0048] (Appendix 4) The noise reduction processing of the original vibration acceleration signal of the rolling work roll to obtain a vibration acceleration signal after noise reduction of the rolling work roll is performed. 2. A feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis according to claim 1, comprising: performing noise reduction processing on a vibration acceleration signal of a rolling work roll using a wavelet analysis method.

[0049] (Appendix 5) The noise reduction processing of the vibration acceleration signal of the rolling work roll using the wavelet analysis method is Selecting one wavelet base for the original vibration acceleration signal of the rolling work roll, determining one wavelet decomposition layer N, and performing wavelet transformation on the original vibration acceleration signal through N-layer wavelet decomposition; Threshold the high-frequency wavelet coefficients, reserve one threshold value, and when the wavelet coefficient is greater than the threshold value, it is controlled by the vibration acceleration signal of the rolling work roll, and when the wavelet coefficient is less than the threshold value, it is controlled by noise. Reserve the low-frequency wavelet coefficients, and use a hard threshold method to perform noise reduction processing for each of the first to Nth layers of high-frequency coefficients; and reconstructing the low-frequency coefficients obtained by wavelet decomposition and the high-frequency coefficients of the first to Nth layers after threshold noise reduction processing by inverse wavelet transform to obtain a vibration acceleration signal of an actual rolling work roll after noise reduction.

[0050] (Appendix 6) Numerical integration of the noise-reduced vibration acceleration signal to obtain a vibration displacement signal of the rolling work roll, performing a first-order integration process on the vibration acceleration signal of the rolling work roll after the noise reduction by a trapezoidal integration method to obtain a vibration velocity signal of the rolling work roll; and performing primary integration processing on the vibration velocity signal of the rolling work roll to obtain a vibration displacement signal of the rolling work roll.

[0051] (Appendix 7) Acquiring fluctuation data of the thickness of the strip at the exit of the rolling mill based on the relationship between the vibration displacement signal of the rolling work roll and the thickness of the strip at the exit of the rolling mill includes the following steps: According to the rolling mill bounce equation, the thickness value of the strip at the exit of the rolling mill in the rolling process is obtained, and the thickness value of the strip at the exit of the rolling mill in the rolling process is calculated according to the following formula: h=S p +s(t) Here, h is the thickness value of the strip at the exit of the rolling mill in the rolling process, and S p is the roll gap value when the rolling mill is loaded, s(t) is the vibration displacement of the rolling work roll, The roll gap of the rolling mill under load is calculated by the following formula: S p =S′+P / C′ where S′ is the roll gap of the rolling mill when no load is applied, P is the preset rolling force of the rolling mill, and C′ is the total stiffness of the base of the rolling mill. Based on the set value of the strip thickness at the exit of the rolling mill and the thickness value in the actual rolling operation, the fluctuation amount of the strip thickness in the actual rolling process is calculated according to the following formula: Δh=h 0 -h Here, Δh is the amount of variation in the thickness of the strip during actual rolling operation, and h 0 is a set thickness value of the strip at the exit of the rolling mill, and h is a thickness value of the strip in actual rolling operation.

[0052] (Appendix 8) Calculating the roll gap adjustment amount of the next stand based on the fluctuation data of the thickness of the strip at the exit of the rolling mill of the previous stand, and performing the roll gap adjustment by the rolling control system of the rolling mill in accordance with the calculated roll gap adjustment amount includes the following steps: Based on the amount of fluctuation in the thickness of the strip during the actual rolling operation of the rolling mill, the roll gap adjustment amount is calculated according to the following formula: ΔS=Δh Q / C′ Here, ΔS is the roll gap adjustment amount, Δh is the fluctuation value of the strip thickness, Q is the plasticity coefficient of the strip, and C′ is the total rigidity of the base of the rolling mill. According to the distance between the roll gaps of the rolling mills of the continuous rolling mill unit and the moving speed of the strip, calculate the time delay amount of the roll gap adjustment by the rolling mill control system according to the following formula: Δt=L / V where Δt is the time delay of the roll gap adjustment by the rolling mill, L is the distance between the roll gaps of the continuous rolling mill unit, and V is the motion speed of the strip between the stands. 2. A feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis as described in Appendix 1, characterized in that after a time delay of Δt, a roll gap adjustment is performed by a rolling mill reduction system.

Claims

1. Acquiring an original vibration acceleration signal of the rolling work roll in a rolling process by an acceleration sensor disposed on a bearing stand of the rolling work roll; performing noise reduction processing on the original vibration acceleration signal of the rolling work roll to obtain a noise-reduced vibration acceleration signal of the rolling work roll; Numerical integration of the noise-reduced vibration acceleration signal to obtain a vibration displacement signal of the rolling work roll; Obtaining fluctuation data of the thickness of the strip at the exit of the rolling mill based on a relationship between the vibration displacement signal of the rolling work roll and the thickness of the strip at the exit of the rolling mill; Calculating a roll gap adjustment amount for the next stand based on fluctuation data of the thickness of the strip at the exit of the rolling mill of the previous stand, and performing roll gap adjustment by a rolling control system of the rolling mill according to the calculated roll gap adjustment amount to control the thickness of the strip. Obtaining fluctuation data of the thickness of the strip at the exit of the rolling mill based on the relationship between the vibration displacement signal of the rolling work roll and the thickness of the strip at the exit of the rolling mill includes the following steps: According to the rolling mill bounce equation, the thickness value of the strip at the exit of the rolling mill in the rolling process is obtained, and the thickness value of the strip at the exit of the rolling mill in the rolling process is calculated according to the following formula: h = S p + s (t) Here, h is the thickness value of the strip at the exit of the rolling mill in the rolling process, S p is the roll gap value under load of the rolling mill, and s(t) is the vibration displacement of the rolling work roll. The roll gap of the rolling mill under load is calculated by the following formula: S p =S'+P / C' where S′ is the roll gap of the rolling mill when no load is applied, P is the preset rolling force of the rolling mill, and C′ is the total stiffness of the base of the rolling mill. Based on the set thickness value of the strip at the exit of the rolling mill and the thickness value in the actual rolling operation, the fluctuation amount of the strip thickness in the actual rolling process is calculated according to the following formula: Δh=h 0 −h Here, Δh is the amount of fluctuation in the thickness of the strip during actual rolling operation, h 0 is the set thickness value of the strip at the exit of the rolling mill, and h is the thickness value of the strip during actual rolling operation. Calculating a roll gap adjustment amount of a next stand based on fluctuation data of the thickness of the strip at the exit of the rolling mill of the previous stand, and performing roll gap adjustment by a rolling control system of the rolling mill in accordance with the calculated roll gap adjustment amount includes the following steps: Based on the amount of fluctuation in the thickness of the strip during the actual rolling operation of the rolling mill, the roll gap adjustment amount is calculated according to the following formula: ΔS=Δh·Q / C′ Here, ΔS is the roll gap adjustment amount, Δh is the fluctuation value of the strip thickness, Q is the plasticity coefficient of the strip, and C′ is the total rigidity of the base of the rolling mill. According to the distance between the roll gaps of the rolling mills of the continuous rolling mill unit and the moving speed of the strip, calculate the time delay amount of the roll gap adjustment by the rolling mill control system according to the following formula: Δt=L / V where Δt is the time delay of the roll gap adjustment by the rolling mill, L is the distance between the roll gaps of the continuous rolling mill unit, and V is the motion speed of the strip between the stands. A feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis, characterized in that after a time delay of Δt, roll gap adjustment is performed by the rolling mill reduction system.

2. Obtaining the original vibration acceleration signal of the rolling work roll in the rolling process includes:

2. The feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis according to claim 1, further comprising: before the rolling process is started, an acceleration sensor with a magnetic base is attached in a vertical direction of the rolling work roll; and when the rolling process is started, the acceleration sensor collects an original vertical vibration acceleration signal of the rolling work roll.

3. The feedforward thickness control method for a hot continuous rolling mill based on work roll vibration test analysis according to claim 1, characterized in that the acceleration sensor is an ICP one-axis acceleration sensor with a sensitivity of 250.

4. The noise reduction processing of the original vibration acceleration signal of the rolling work roll to obtain a vibration acceleration signal after noise reduction of the rolling work roll is performed.

2. The method for feedforward thickness control of a hot continuous rolling mill based on analysis of work roll vibration tests according to claim 1, further comprising: using wavelet analysis to reduce noise in the vibration acceleration signal of the rolling work roll.

5. The noise reduction processing of the vibration acceleration signal of the rolling work roll using the wavelet analysis method is Selecting one wavelet basis for the original vibration acceleration signal of the rolling work roll, determining one wavelet decomposition layer N, and performing wavelet transformation on the original vibration acceleration signal through N-layer wavelet decomposition; Threshold the high-frequency wavelet coefficients, reserve one threshold value, and when the wavelet coefficient is greater than the threshold value, it is controlled by the vibration acceleration signal of the rolling work roll, and when the wavelet coefficient is less than the threshold value, it is controlled by noise. Reserve the low-frequency wavelet coefficients, and use a hard threshold method to perform noise reduction processing for each of the first to Nth layers of high-frequency coefficients; and reconstructing the low-frequency coefficients obtained by the wavelet decomposition and the high-frequency coefficients of the first to Nth layers after the threshold noise reduction process by inverse wavelet transform to obtain the vibration acceleration signal of the actual rolling work roll after noise reduction.

6. Numerical integration of the noise-reduced vibration acceleration signal to obtain a vibration displacement signal of the rolling work roll, performing a first-order integration process on the vibration acceleration signal of the rolling work roll after the noise reduction by a trapezoidal integration method to obtain a vibration velocity signal of the rolling work roll; and performing first-order integration processing on the vibration velocity signal of the rolling work roll to obtain a vibration displacement signal of the rolling work roll.

Images