A method for automatic thickness control of asynchronously rolled ultra-thin metal strips

Abstract

The present application discloses a method for automatic thickness control of asynchronously rolled ultra-thin metal strips, which is completed by a rolling mill mechanical device and a rolling mill control system. The method combines the two modes of roll gap adjustment and speed ratio adjustment to realize the automatic thickness control function of asynchronously rolled ultra-thin metal strips. The roll gap adjustment mode is used when the pressure is sensitive to the rolling force, and the speed ratio adjustment mode is used when it is not sensitive, which is conducive to improving the thickness accuracy and yield rate of the ultra-thin strips and reducing the requirements for operators.

Description

Technical Field

[0001] The present application relates to metal thin strip processing, and in particular to a method for automatically controlling the thickness of an asynchronously rolled ultra-thin metal strip. Background Art

[0002] In recent years, with the development of industries such as aerospace, biomedicine, 5G, electric vehicles, and micro-electromechanical systems, the market demand for high-quality, low-cost ultra-thin metal strips has risen sharply. Due to the minimum rollable thickness phenomenon in the traditional synchronous rolling process, ultra-thin metal strips of high-strength materials are mostly rolled using multi-roll mills with small working roll diameters and high roll stiffness, such as the Sendzimir mill. Multi-roll mills are complex equipment, require large initial investments, are difficult to maintain, and have low overall production efficiency, making the cost of producing ultra-thin metal strips too high to meet market needs.

[0003] Different from traditional synchronous rolling, asynchronous rolling has different upper and lower working roll speeds. In addition to the front slip zone and the back slip zone, there is also a third stress state zone in the rolling deformation zone: the rolling zone. The existence of the rolling zone allows asynchronous rolling to break through the minimum rollable thickness limit of traditional synchronous rolling, and the required equipment is simple, low cost, and easy to maintain. It is a potential technology for producing ultra-thin metal strips with high efficiency and low cost.

[0004] The traditional synchronous rolling automatic thickness control means is usually only to adjust the roll gap, but due to the minimum rollable thickness phenomenon of synchronous rolling, when the thickness of the rolled piece is very thin, the effect of adjusting the roll gap is often very poor. Asynchronous rolling can break through the minimum rollable thickness limit of traditional synchronous rolling, and the means of controlling the reduction include adjusting the speed ratio in addition to adjusting the roll gap. However, there are many asynchronous rolling process parameters, such as speed ratio, rolling force, front and rear tension, deformation resistance of rolled piece, configuration of rolling deformation zone and proportion of each zone, and the parameters are coupled with each other and difficult to adjust. The existing asynchronous rolling technology cannot realize automatic thickness control, which makes its product thickness accuracy poor and has high requirements on operators, limiting the application of asynchronous rolling technology. Summary of the invention

[0005] The purpose of the present invention is to provide a method for automatic thickness control of asynchronously rolled ultra-thin metal strips, which can realize the function of automatically controlling the thickness of rolled pieces during asynchronous rolling of ultra-thin metal strips, improve the thickness accuracy of ultra-thin strip products, and reduce the requirements for operators.

[0006] To achieve the above object, the present invention provides the following technical solutions.

[0007] The embodiment of the present application discloses a method for automatically controlling the thickness of an asynchronously rolled ultra-thin metal strip, which is accomplished by a rolling mill mechanical device and a rolling mill control system.

[0008] The rolling mill mechanical device includes a first reel, a first steering roller, a first speed measuring roller, a second steering roller, a first thickness gauge, a memorial arch, a second thickness gauge, a third steering roller, a second speed measuring roller, a fourth steering roller, and a second reel, which are arranged in sequence along the rolling direction of the rolled piece. An upper working roller and a lower working roller correspondingly acting on the top surface and the bottom surface of the rolled piece are arranged in the memorial arch. An upper support roller and a lower support roller are arranged above the upper working roller and below the lower working roller, respectively. A pressing hydraulic cylinder is arranged above the upper support roller, and the pressing hydraulic cylinder acts on the upper support roller and drives the upper working roller to adjust the The roll gap distance between the upper working roll and the lower working roll, the upper working roll is driven by a first main motor, and the lower working roll is driven by a second main motor, the first main motor and the second main motor are respectively located on both sides of the arch and are controlled separately, the linear speed ratio of the upper working roll and the lower working roll is adjusted by controlling the speed of the first main motor and the second main motor, the first reel is driven by a first winding motor, and the second reel is driven by a second winding motor, the first main motor, the second main motor, the first winding motor, and the second winding motor are all reversible motors,

[0009] The rolling mill control system includes measuring sensors, an operating table, an industrial computer, a control cabinet, a PLC and a four-quadrant frequency converter. The measuring sensors include a rolling force sensor for measuring the rolling force of the pressing hydraulic cylinder, a first tension force sensor and a second tension force sensor for measuring the entrance tension and exit tension of the rolled piece, a first main motor speed encoder and a second main motor speed encoder for measuring and controlling the rotation speeds of the first main motor and the second main motor, a first winding motor speed encoder and a second winding motor speed encoder for measuring and controlling the rotation speeds of the first winding motor and the second winding motor, a first rolling speed encoder and a second rolling speed encoder for measuring the entrance and exit speeds of the rolled piece, and the first thickness gauge and the second thickness gauge for measuring the entrance and exit thickness of the rolled piece.

[0010] The method for automatic thickness control of asynchronously rolled ultra-thin metal strip comprises the following steps in sequence:

[0011] S1 Set basic rolling parameters, including reference rolling force , Base speed ratio , Maximum rolling force , thickness control accuracy , Exit thickness correction factor , Allowable value of rolling force sensitivity coefficient , Rolling force sensitivity coefficient calculation cumulative time And the thickness of the rolled piece at each pass , Target outlet thickness , front tension and back tension;

[0012] S2 adopts the roll gap adjustment mode. Press the roll gap adjustment mode button to start. At this time, the speed ratio Increase to base speed ratio The thickness of the rolled piece can be automatically controlled by adjusting the hydraulic cylinder. When rolling in the left direction, the lower working roll is a fast roll with a different speed ratio. is the ratio of the linear speed of the lower working roll to the linear speed of the upper working roll; when rolling in the right direction, the upper working roll is a fast roll, and the speed ratio is the ratio of the linear speed of the upper working roll to the linear speed of the lower working roll;

[0013] S3 Measurement and correction of the thickness of rolled products at the exit , the thickness of rolled product at the outlet By formula The result is obtained by real-time calculation, where the thickness of the rolled piece at the entrance is , Target outlet thickness and outlet thickness correction factor is the set value, the measured value of the thickness at the exit of the rolled piece , rolling stock entrance speed and exit speed It is the real-time measurement value. When rolling in right direction, The second thickness gauge measures in real time. and The results are measured in real time by the first rolling speed encoder and the second rolling speed encoder respectively; when rolling in the left direction, The first thickness gauge measures the thickness in real time. and The values ​​are respectively obtained by real-time measurement by the second rolling speed measuring encoder and the first rolling speed measuring encoder;

[0014] S4 Real-time comparison of target outlet thickness value With measured value , automatically adjust the hydraulic cylinder to adjust the roll gap, realize automatic thickness control, and change the outlet thickness of the rolled piece measured and corrected in step S3 and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and When the hydraulic cylinder is pressed down, the roll gap is reduced; when and When the hydraulic cylinder is lifted, the roller gap increases; when When the hydraulic cylinder is pressed down, it does not move and the roll gap remains unchanged;

[0015] S5 real-time measurement of rolling forces And calculate the rolling force sensitivity coefficient , comparing the rolling force measurements With maximum rolling force and compare the calculated values ​​of rolling force sensitivity coefficient and allowable value , determine whether to switch to the thickness automatic control mode, rolling force sensitivity coefficient The calculation formula is , where Calculate the cumulative time for the rolling force sensitivity coefficient Internal rolling force The added value, Calculate the cumulative time for the rolling force sensitivity coefficient Internal rolled product outlet thickness The reduction value of rolling force sensitivity coefficient Characterize the pressing effect of roll gap adjustment, The larger the value, the more obvious the pressure is when the roll gap is reduced. and When , return to step S3 and continue to use the roller gap adjustment mode; when or When , the switching mode indicator light comes on, switching to the speed ratio adjustment mode;

[0016] S6 adopts variable speed ratio adjustment mode, rolling force Automatically reduce to the reference rolling force The rolling mill realizes automatic thickness control by adjusting the speed ratio. When rolling in the left direction, the lower working roll is a fast roll and the speed ratio is is the ratio of the linear speed of the lower working roll to the linear speed of the upper working roll; when rolling in the right direction, the upper working roll is a fast roll, and the speed ratio is the ratio of the linear speed of the upper working roll to the linear speed of the lower working roll;

[0017] S7 Measurement and correction of the exit thickness of rolled products , the specific operation is the same as step S3;

[0018] S8 real-time comparison of target outlet thickness value With measured value , automatically adjust the speed ratio, realize automatic thickness control, and convert the thickness of the rolled product measured and corrected in step S7 into and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and When the speed of the fast roller is increased, the speed ratio increases; when and When the fast roller speed is reduced, the speed ratio is reduced; when When the speed ratio between the first main motor and the second main motor remains unchanged, the speed ratio remains unchanged;

[0019] S9 repeats step S7 and step S8 until the rolled piece is thinned to a target thickness allowable range.

[0020] Preferably, in the above-mentioned method for automatic thickness control of asynchronously rolled ultra-thin metal strip, the first main motor drives the upper working roll through the first main reducer and the first coupling in sequence, the second main motor drives the lower working roll through the second main reducer and the second coupling in sequence, the first winding motor drives the first reel through the first winding reducer, and the second winding motor drives the second reel through the second winding reducer.

[0021] Preferably, in the above-mentioned method for automatic thickness control of asynchronously rolled ultra-thin metal strip, the first steering roller, the first speed measuring roller, the second steering roller, the third steering roller, the second speed measuring roller, and the fourth steering roller are all hollow rollers with the same diameter and are all passive rollers, which are dragged by the friction force exerted by the rolled piece.

[0022] Preferably, in the above-mentioned method for automatic thickness control of asynchronously rolled ultra-thin metal strip, the center height of the first speed measuring roller is higher than the top heights of the first steering roller and the second steering roller, the center distance between the first steering roller and the second steering roller is less than 2 times the diameter of the first speed measuring roller, the rolled piece passes through the bottom of the first steering roller, the top of the first speed measuring roller and the bottom of the second steering roller in sequence, and forms a wrap angle greater than 180° on the first speed measuring roller; the center height of the second speed measuring roller is higher than the top heights of the third steering roller and the fourth steering roller, the center distance between the third steering roller and the fourth steering roller is less than 2 times the diameter of the second speed measuring roller, the rolled piece passes through the bottom of the third steering roller, the top of the second speed measuring roller and the bottom of the fourth steering roller in sequence, and forms a wrap angle greater than 180° on the second speed measuring roller.

[0023] Preferably, in the above-mentioned method for automatic thickness control of asynchronously rolled ultra-thin metal strip, the rolling force sensor is located below the pressing hydraulic cylinder, the first tension force sensor is located below the first speed measuring roller, the second tension force sensor is located below the second speed measuring roller, the first main motor speed encoder is installed on the rotor shaft of the first main motor, the second main motor speed encoder is installed on the rotor shaft of the second main motor, the first winding motor speed encoder is installed on the rotor shaft of the first winding motor, the second winding motor speed encoder is installed on the rotor shaft of the second winding motor, the first rolling speed encoder is installed on one side of the first speed measuring roller, and the second rolling speed encoder is installed on one side of the second speed measuring roller.

[0024] Preferably, in the above-mentioned method for automatic thickness control of asynchronously rolled metal ultra-thin strips, the industrial computer is equipped with a control system human-machine interface configured with WinCC, and the human-machine interface has the thickness of each pass of the rolled piece at the entrance. Input domain, target outlet thickness Input field, front tension input field and back tension input field, reference rolling force Input domain, base speed ratio Input field, maximum rolling force Input domain, thickness control accuracy Input domain, outlet thickness correction factor Input domain, allowable value of rolling force sensitivity coefficient Input domain, rolling force sensitivity coefficient calculation cumulative time Input field and PID parameter input field.

[0025] Preferably, in the above-mentioned method for automatic thickness control of asynchronously rolled ultra-thin metal strips, the operating console is provided with a rolling direction bidirectional adjustment switch, a roll gap adjustment mode button, a speed ratio adjustment mode button and a switching mode indicator light.

[0026] Preferably, in the above-mentioned method for automatic control of the thickness of asynchronously rolled ultra-thin metal strip, the four-quadrant inverter is located inside the control cabinet, including a rectifier unit, a common DC bus, a first inverter, a second inverter, a third inverter and a fourth inverter, and the first inverter, the second inverter and the third inverter respectively drive the first main motor, the second main motor, the first winding motor and the second winding motor.

[0027] Compared with the prior art, the advantage of the present invention is that the automatic thickness control function of the asynchronously rolled ultra-thin metal strip is realized by combining the roll gap adjustment mode and the speed ratio adjustment mode. When the thickness of the rolled piece is relatively large and the pressure is sensitive to the increase of the rolling force, the roll gap adjustment mode is adopted; when the thickness of the rolled piece is small and the pressure is not sensitive to the increase of the rolling force, the speed ratio adjustment mode is adopted. It avoids the problems of single thickness automatic control means (only roll gap adjustment mode) in traditional synchronous rolling, the pressure is not sensitive to the roll gap adjustment when the thickness of the rolled piece is thin, and the whole rolling process requires multiple annealing to reduce the deformation resistance of the rolled piece. At the same time, it also avoids the problem of excessive requirements on the main motor and the main reducer caused by the unbalanced load distribution of the fast and slow working rolls in asynchronous rolling when the thickness of the rolled piece is large, and is conducive to giving play to the efficiency advantage of asynchronous rolling in the production process of ultra-thin metal strips. The present invention combines the advantages of roll gap adjustment and speed ratio adjustment, avoids their disadvantages, improves the thickness accuracy, yield rate and production efficiency of ultra-thin metal strips, and reduces the requirements for operators and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of an automatic thickness control device system for asynchronously rolling ultra-thin metal strips in a specific embodiment of the present invention;

[0030] Figure 2 The figure is a schematic top view of a rolling mill mechanical device in a specific embodiment of the present invention;

[0031] Figure 3 The figure shows a schematic front view of a rolling mill mechanical device in a specific embodiment of the present invention;

[0032] Figure 4 Shown is a schematic diagram of a four-quadrant frequency converter in a specific embodiment of the present invention;

[0033] Figure 5 Shown is a flow chart of a method for automatic thickness control of asynchronously rolled ultra-thin metal strips in a specific embodiment of the present invention.

[0034] In the figure: 1, rolling mill mechanical device; 2, industrial computer; 3, operating table; 4, PLC; 5, control cabinet; 6, first coiling reducer; 7, first coiling motor; 8, first coiling motor speed encoder; 9, first rolling speed measuring encoder; 10, first main reducer; 11, first main motor speed encoder; 12, first main motor; 13, second rolling speed measuring encoder; 14, second coiling motor; 15, second coiling motor speed encoder; 16, second coiling reducer; 17, second coupling; 18, second main reducer; 19, second main motor; 20, second main motor speed encoder; 21, first coupling; 22, first reel; 23, rolled piece; 24, The first steering roller; 25, the first speed measuring roller; 26, the second steering roller; 27, the first tension measuring force sensor; 28, the first thickness gauge; 29, the upper support roller; 30, the rolling force measuring force sensor; 31, the hydraulic cylinder; 32, the arch; 33, the upper working roller; 34, the lower working roller; 35, the lower support roller; 36, the second thickness gauge; 37, the second tension measuring force sensor; 38, the third steering roller; 39, the second speed measuring roller; 40, the fourth steering roller; 41, the second reel; 42, the rectifier unit; 43, the four-quadrant inverter; 44, the shared DC bus; 45, the first inverter; 46, the second inverter; 47, the third inverter; 48, the fourth inverter. DETAILED DESCRIPTION

[0035] The following will describe the technical solutions in the embodiments of the present invention in detail in conjunction with the drawings 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.

[0036] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Combination Figure 1-5 As shown, the rolling mill mechanical device 1 of the asynchronous rolling metal ultra-thin strip thickness automatic control device system comprises a first reel 22, a first steering roller 24, a first speed measuring roller 25, a second steering roller 26, a first thickness gauge 28, an arch 32, a second thickness gauge 36, a third steering roller 38, a second speed measuring roller 39, a fourth steering roller 40, and a second reel 41, which are arranged in sequence along the rolling direction of the workpiece 23. The arch 32 is provided with an upper working roller 33 and a lower working roller 34 corresponding to the top and bottom surfaces of the workpiece 23. The upper working roller 33 An upper support roller 29 and a lower support roller 35 are respectively arranged above and below the lower working roller 34. A pressing hydraulic cylinder 31 is arranged above the upper support roller 29. The pressing hydraulic cylinder 31 acts on the upper support roller 29 and drives the upper working roller 33 to adjust the roller gap distance between the upper working roller 33 and the lower working roller 34. The upper working roller 33 is driven by the first main motor 12, the lower working roller 34 is driven by the second main motor 19, the first reel 22 is driven by the first winding motor 7, and the second reel 41 is driven by the second winding motor 14.

[0039] The rolling mill control system includes a rolling force sensor 30 for measuring the rolling force of the hydraulic cylinder 31, a first tension force sensor 27 and a second tension force sensor 37 for measuring the entrance tension and exit tension of the rolled piece 23, a first main motor speed encoder 11 and a second main motor speed encoder 20 for measuring and controlling the rotation speeds of the first main motor 12 and the second main motor 19, a first winding motor speed encoder 8 and a second winding motor speed encoder 15 for measuring and controlling the rotation speeds of the first winding motor 7 and the second winding motor 14, a first rolling speed encoder 9 and a second rolling speed encoder 13 for measuring the entrance and exit speeds of the rolled piece 23, and a first thickness gauge 28 and a second thickness gauge 36 for measuring the entrance and exit thicknesses of the rolled piece 23.

[0040] The first main motor 12, the second main motor 19, the first winding motor 7, and the second winding motor 14 are all reversible motors. The first main motor 12 drives the upper working roll 33 through the first main reducer 10 and the first coupling 21 in sequence, the second main motor 19 drives the lower working roll 34 through the second main reducer 18 and the second coupling 17 in sequence, the first winding motor 7 drives the first reel 22 through the first winding reducer 6, and the second winding motor 14 drives the second reel 41 through the second winding reducer 16. The first steering roller 24, the first speed measuring roller 25, the second steering roller 26, the third steering roller 38, the second speed measuring roller 39, and the fourth steering roller 40 are all hollow rollers with the same diameter and are all passive rollers, which are dragged by the friction force applied by the rolled piece 23. The center height of the first speed measuring roller 25 is higher than the top heights of the first steering roller 24 and the second steering roller 26, and the center distance between the first steering roller 24 and the second steering roller 26 is less than twice the diameter of the first speed measuring roller 25. The rolled piece 23 passes through the bottom of the first steering roller 24, the top of the first speed measuring roller 25 and the bottom of the second steering roller 26 in sequence, and forms a wrap angle greater than 180° on the first speed measuring roller 25; the center height of the second speed measuring roller 39 is higher than the top heights of the third steering roller 38 and the fourth steering roller 40, and the center distance between the third steering roller 38 and the fourth steering roller 40 is less than twice the diameter of the second speed measuring roller 39. The rolled piece 23 passes through the bottom of the third steering roller 38, the top of the second speed measuring roller 39 and the bottom of the fourth steering roller 40 in sequence, and forms a wrap angle greater than 180° on the second speed measuring roller 39. The force sensor 30 for measuring the rolling force is located below the pressing hydraulic cylinder 31, the first tension measuring force sensor 27 is located below the first speed measuring roller 25, the second tension measuring force sensor 37 is located below the second speed measuring roller 39, the first main motor speed encoder 11 is installed on the rotor shaft of the first main motor 12, the second main motor speed encoder 20 is installed on the rotor shaft of the second main motor 19, the first winding motor speed encoder 8 is installed on the rotor shaft of the first winding motor 7, the second winding motor speed encoder 15 is installed on the rotor shaft of the second winding motor 14, the first rolling speed encoder 9 is installed on one side of the first speed measuring roller 25, and the second rolling speed encoder 13 is installed on one side of the second speed measuring roller 39.

[0041] The two main motor speed encoders are used to measure and control the linear speed of the upper and lower working rolls, control the speed ratio, and adjust the pressure reduction. The measurement calculation formula is: , where is the linear speed of the working roll (m / min), is the main motor speed (rpm), is the working roll diameter (mm), The reduction ratio of the main reducer.

[0042] The two winding motor speed encoders are used to measure the winding motor speed, calculate the coil diameter, and control the winding and unwinding tension; the two rolling speed encoders are used to measure the entry and exit speeds of the rolled piece, calculate the coil diameter and reduction rate, and control the tension and reduction; the two thickness gauges are used to measure the entry and exit thickness of the rolled piece and control the reduction.

[0043] It also includes an industrial computer 2, an operation console 3, a PLC 4, and a control cabinet 5. The operation console 3 is provided with a rolling direction bidirectional adjustment switch, a roll gap adjustment mode button and an indicator light, and a speed ratio adjustment mode button and an indicator light. It also includes a four-quadrant frequency converter 43. The four-quadrant frequency converter 43 is located inside the control cabinet 5 and includes a rectifier unit 42, a common DC bus 44, a first inverter 45, a second inverter 46, a third inverter 47, and a fourth inverter 48. The first inverter 45, the second inverter 46, and the third inverter 47 drive the first main motor 12, the second main motor 19, the first winding motor 7, and the second winding motor 14, respectively.

[0044] Industrial computer 2 is equipped with a WinCC-configured control system human-machine interface, on which the thickness of the rolled piece at each pass is displayed. Input domain, target outlet thickness Input field, front tension input field and back tension input field, reference rolling force Input domain, base speed ratio Input field, maximum rolling force Input domain, thickness control accuracy Input domain, outlet thickness correction factor Input domain, allowable value of rolling force sensitivity coefficient Input domain, rolling force sensitivity coefficient calculation cumulative time Input field and PID parameter input field.

[0045] The following will use specific values ​​as an example:

[0046] The upper limit of the rolling force sensor is 150t, the maximum limit of the speed ratio is 2.0, the material of the rolled piece is 430 stainless steel, the thickness is 150μm, and the width is 100.0mm.

[0047] The method for automatic thickness control of asynchronously rolled ultra-thin metal strips comprises:

[0048] Step 1: Set the following basic rolling parameters, benchmark rolling force , Base speed ratio , Maximum rolling force , thickness control accuracy , Exit thickness correction factor , Allowable value of rolling force sensitivity coefficient , Rolling force sensitivity coefficient calculation cumulative time , Entrance thickness of 4-pass rolled product The target outlet thickness is 150, 100, 75 and 60 μm respectively. 100, 75, 60 and 50 μm respectively;

[0049] Step 2: Press the roll gap adjustment mode button. At this time, the thickness automatic control mode of the rolling mill is the roll gap adjustment mode, and the speed ratio , turn the rolling direction adjustment two-way switch to left rolling, start the rolling mill, at this time the lower working roll is a fast roll, and the linear speed of the lower working roll is 1.1 times that of the upper working roll;

[0050] Step 3: The first thickness gauge measures the thickness of the rolled piece at the exit in real time The second rolling speed encoder and the first rolling speed encoder measure in real time and calculate the rolling stock entrance speed through PLC and industrial computer. and exit speed , combined with the set entry thickness of the rolled piece , Target outlet thickness and outlet thickness correction factor , according to the formula Real-time calculation of the corrected thickness of the rolled product at the exit ;

[0051] Step 4: Correct the thickness of the rolled product and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and ,Right now When , press the hydraulic cylinder down; when and ,Right now When the hydraulic cylinder is pressed down, it is lifted up, and the hydraulic cylinder is pressed down by and The absolute value of the difference Relationship control to ensure ;

[0052] Step 5: Measure the rolling force using a force sensor to measure the rolling force in real time , the industrial computer is measured by historical and corrected Calculate the rolling force sensitivity coefficient and calculate the cumulative time Inside and The increase in the rolling force sensitivity coefficient is further calculated. , comparing the rolling force measurements With maximum rolling force and compare the calculated values ​​of rolling force sensitivity coefficient and allowable value ,Discover and , return to step three;

[0053] Turn the rolling direction adjustment two-way switch to right rolling and start the rolling mill. At this time, the upper working roll is a fast roll, and the linear speed of the upper working roll is 1.1 times that of the lower working roll. The second thickness gauge measures the thickness of the rolled piece at the exit in real time. The first rolling speed encoder and the second rolling speed encoder measure and calculate the rolling stock entrance speed in real time. and exit speed , combined with the set second pass entry thickness , Target outlet thickness and outlet thickness correction factor , according to the formula Real-time calculation of the corrected thickness of the rolled product at the exit , the corrected and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and ,Right now When , press the hydraulic cylinder down; when and ,Right now When the hydraulic cylinder is pressed down, it is lifted;

[0054] Continue to use the rolling force sensor to measure the rolling force in real time , the industrial computer is measured by historical and corrected Calculation of rolling force sensitivity coefficient Comparison of rolling force measurements With maximum rolling force and compare the calculated values ​​of rolling force sensitivity coefficient and allowable value ,Discover ,but , the switch mode indicator light turns on;

[0055] Step 6: Turn the rolling direction adjustment two-way switch to left rolling, the thickness automatic control mode automatically switches to the speed ratio adjustment mode, and the rolling force Automatically reduce to the reference rolling force , start the rolling mill, at this time the upper working roll is a slow roll and the lower working roll is a fast roll;

[0056] Step 7: The first thickness gauge measures the thickness of the rolled piece at the exit in real time The second rolling speed encoder and the first rolling speed encoder measure in real time and calculate the rolling stock entrance speed through PLC and industrial computer. and exit speed , combined with the set entry thickness of the rolled piece , Target outlet thickness and outlet thickness correction factor , according to the formula Real-time calculation of the corrected thickness of the rolled product at the exit ;

[0057] Step 8: Correct the thickness of the rolled product and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and ,Right now When , increase the speed of the second main motor; when and ,Right now When the speed of the lower fast roller is reduced, the speed ratio of the two main motors changes by and The absolute value of the difference Relationship control to ensure ;

[0058] Step 9: Repeat steps 7 and 8 until the rolled piece is thinned to the target thickness. .

[0059] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0060] The above is only a specific implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for automatic thickness control of asynchronously rolled ultra-thin metal strips, characterized in that: This is accomplished through the mill mechanical device and the mill control system. The rolling mill mechanical device includes a first reel, a first steering roller, a first speed measuring roller, a second steering roller, a first thickness gauge, a memorial arch, a second thickness gauge, a third steering roller, a second speed measuring roller, a fourth steering roller, and a second reel, which are arranged in sequence along the rolling direction of the rolled piece. An upper working roller and a lower working roller correspondingly acting on the top surface and the bottom surface of the rolled piece are arranged in the memorial arch. An upper support roller and a lower support roller are arranged above the upper working roller and below the lower working roller, respectively. A pressing hydraulic cylinder is arranged above the upper support roller, and the pressing hydraulic cylinder acts on the upper support roller and drives the upper working roller to adjust the The roll gap distance between the upper working roll and the lower working roll, the upper working roll is driven by a first main motor, and the lower working roll is driven by a second main motor, the first main motor and the second main motor are respectively located on both sides of the arch and are controlled separately, the linear speed ratio of the upper working roll and the lower working roll is adjusted by controlling the speed of the first main motor and the second main motor, the first reel is driven by a first winding motor, and the second reel is driven by a second winding motor, the first main motor, the second main motor, the first winding motor, and the second winding motor are all reversible motors, The rolling mill control system includes measuring sensors, an operating table, an industrial computer, a control cabinet, a PLC and a four-quadrant frequency converter. The measuring sensors include a rolling force sensor for measuring the rolling force of the pressing hydraulic cylinder, a first tension force sensor and a second tension force sensor for measuring the entrance tension and exit tension of the rolled piece, a first main motor speed encoder and a second main motor speed encoder for measuring and controlling the rotation speeds of the first main motor and the second main motor, a first winding motor speed encoder and a second winding motor speed encoder for measuring and controlling the rotation speeds of the first winding motor and the second winding motor, a first rolling speed encoder and a second rolling speed encoder for measuring the entrance and exit speeds of the rolled piece, and the first thickness gauge and the second thickness gauge for measuring the entrance and exit thickness of the rolled piece. The functions of the first main motor speed encoder and the second main motor speed encoder are to measure and control the linear speed of the upper working roll and the lower working roll, control the speed ratio, and adjust the pressing amount. The measurement calculation formula is: , where is the linear speed of the working roll (m / min), is the main motor speed (rpm), is the working roll diameter (mm), is the reduction ratio of the main reducer, The method for automatic thickness control of asynchronously rolled ultra-thin metal strip comprises the following steps in sequence: S1 Set basic rolling parameters, including reference rolling force , Base speed ratio , Maximum rolling force , thickness control accuracy , Exit thickness correction factor , Allowable value of rolling force sensitivity coefficient , Rolling force sensitivity coefficient calculation cumulative time And the thickness of the rolled piece at each pass , Target outlet thickness , front tension and back tension; S2 adopts the roll gap adjustment mode. Press the roll gap adjustment mode button to start. At this time, the speed ratio Increase to base speed ratio The thickness of the rolled piece can be automatically controlled by adjusting the hydraulic cylinder. When rolling in the left direction, the lower working roll is a fast roll with a different speed ratio. is the ratio of the linear speed of the lower working roll to the linear speed of the upper working roll; when rolling in the right direction, the upper working roll is a fast roll, and the speed ratio is the ratio of the linear speed of the upper working roll to the linear speed of the lower working roll; S3 Measurement and correction of the thickness of the rolled product at the exit , the thickness of rolled product at the outlet By formula The result is obtained by real-time calculation, where the thickness of the rolled piece at the entrance is , Target outlet thickness and outlet thickness correction factor is the set value, the measured value of the thickness at the exit of the rolled piece , rolling stock entrance speed and exit speed It is the real-time measurement value. When rolling in right direction, The second thickness gauge measures in real time. and The results are measured in real time by the first rolling speed encoder and the second rolling speed encoder respectively; when rolling in the left direction, The first thickness gauge measures the thickness in real time. and The values ​​are respectively obtained by real-time measurement by the second rolling speed measuring encoder and the first rolling speed measuring encoder; S4 Real-time comparison of target outlet thickness value With measured value , automatically adjust the hydraulic cylinder to adjust the roll gap, realize automatic thickness control, and change the outlet thickness of the rolled piece measured and corrected in step S3 and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and When the hydraulic cylinder is pressed down, the roll gap is reduced; when and When the hydraulic cylinder is lifted, the roller gap increases; when When the hydraulic cylinder is pressed down, it does not move and the roll gap remains unchanged; S5 real-time measurement of rolling forces And calculate the rolling force sensitivity coefficient , comparing the rolling force measurements With maximum rolling force and compare the calculated values ​​of rolling force sensitivity coefficient and allowable value , determine whether to switch to the thickness automatic control mode, rolling force sensitivity coefficient The calculation formula is , where Calculate the cumulative time for the rolling force sensitivity coefficient Internal rolling force The added value, Calculate the cumulative time for the rolling force sensitivity coefficient Internal rolled product outlet thickness The reduction value of rolling force sensitivity coefficient Characterize the pressing effect of roll gap adjustment, The larger the value, the more obvious the pressure is when the roll gap is reduced. and When , return to step S3 and continue to use the roller gap adjustment mode; when or When , the switching mode indicator light comes on, switching to the speed ratio adjustment mode; S6 adopts variable speed ratio adjustment mode, rolling force Automatically reduce to the reference rolling force The rolling mill realizes automatic thickness control by adjusting the speed ratio. When rolling in the left direction, the lower working roll is a fast roll and the speed ratio is is the ratio of the linear speed of the lower working roll to the linear speed of the upper working roll; when rolling in the right direction, the upper working roll is a fast roll, and the speed ratio is the ratio of the linear speed of the upper working roll to the linear speed of the lower working roll; S7 Measurement and correction of the exit thickness of rolled products , the specific operation is the same as step S3; S8 real-time comparison of target outlet thickness value With measured value , automatically adjust the speed ratio, realize automatic thickness control, and convert the thickness of the rolled product measured and corrected in step S7 into and target outlet thickness Absolute value of difference and thickness control accuracy For comparison, and When the speed of the fast roller is increased, the speed ratio increases; when and When the fast roller speed is reduced, the speed ratio is reduced; when When , the speed ratio between the first main motor and the second main motor remains unchanged, and the speed ratio remains unchanged; S9 repeats step S7 and step S8 until the rolled piece is thinned to a target thickness allowable range.

2. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The first main motor drives the upper working roll through the first main reducer and the first coupling in sequence, the second main motor drives the lower working roll through the second main reducer and the second coupling in sequence, the first winding motor drives the first reel through the first winding reducer, and the second winding motor drives the second reel through the second winding reducer.

3. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The first steering roller, the first speed measuring roller, the second steering roller, the third steering roller, the second speed measuring roller and the fourth steering roller are all hollow rollers with the same diameter and are all passive rollers, which are dragged by the friction force applied by the rolled piece.

4. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The center height of the first speed measuring roller is higher than the top heights of the first steering roller and the second steering roller, the center distance between the first steering roller and the second steering roller is less than 2 times the diameter of the first speed measuring roller, the rolled piece passes through the bottom of the first steering roller, the top of the first speed measuring roller and the bottom of the second steering roller in sequence, and forms a wrap angle greater than 180° on the first speed measuring roller; the center height of the second speed measuring roller is higher than the top heights of the third steering roller and the fourth steering roller, the center distance between the third steering roller and the fourth steering roller is less than 2 times the diameter of the second speed measuring roller, the rolled piece passes through the bottom of the third steering roller, the top of the second speed measuring roller and the bottom of the fourth steering roller in sequence, and forms a wrap angle greater than 180° on the second speed measuring roller.

5. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The rolling force measuring force sensor is located below the pressing hydraulic cylinder, the first tension measuring force sensor is located below the first speed measuring roller, the second tension measuring force sensor is located below the second speed measuring roller, the first main motor speed encoder is installed on the rotor shaft of the first main motor, the second main motor speed encoder is installed on the rotor shaft of the second main motor, the first winding motor speed encoder is installed on the rotor shaft of the first winding motor, the second winding motor speed encoder is installed on the rotor shaft of the second winding motor, the first rolling speed measuring encoder is installed on one side of the first speed measuring roller, and the second rolling speed measuring encoder is installed on one side of the second speed measuring roller.

6. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The industrial computer is equipped with a WinCC configuration control system human-machine interface, on which the thickness of the entry of each pass of the rolled piece is displayed. Input domain, target outlet thickness Input field, front tension input field and back tension input field, reference rolling force Input domain, base speed ratio Input field, maximum rolling force Input domain, thickness control accuracy Input domain, outlet thickness correction factor Input domain, allowable value of rolling force sensitivity coefficient Input domain, rolling force sensitivity coefficient calculation cumulative time Input field and PID parameter input field.

7. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The operating table is provided with a rolling direction bidirectional adjustment switch, a roll gap adjustment mode button, a speed ratio adjustment mode button and a switching mode indicator light.

8. The method for automatic thickness control of asynchronously rolled ultra-thin metal strip according to claim 1, characterized in that: The four-quadrant inverter is located inside the control cabinet, and includes a rectifier unit, a shared DC bus, a first inverter, a second inverter, a third inverter and a fourth inverter. The first inverter, the second inverter and the third inverter respectively drive the first main motor, the second main motor, the first winding motor and the second winding motor.

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