Camber control device for a continuous rolling mill

Abstract

Provided is a camber control device for a continuous rolling mill, capable of reducing a camber in a tip part of a rolling material and suppressing the occurrence of telescoping of a steel strip coil. In this invention, a tip camber measurement unit calculates a tip camber measurement value at a rolling material tip part on the basis of a meandering amount of the rolling material detected by a meandering amount detector. A camber rectification leveling computation unit calculates a camber rectification leveling amount on the basis of the tip camber measurement value. A tip leveling setting unit sets a tip leveling control length and a tip leveling correction amount for reducing the tip camber for a reduction leveling device of each rolling stand. A reduction leveling control unit adjusts the reduction leveling device to a tip-leveling-correction-amount-added position before the rolling material enters the each rolling stand and adjusts the position of the reduction leveling device in such a manner that the tip leveling correction amount gradually decreases after the rolling length at the each rolling stand has reached the tip leveling control length.

Description

Technical Field

[0001] The present disclosure relates to a caster control device for a continuous rolling mill such as a hot finish rolling mill, and more particularly to a continuous rolling mill including a plurality of rolling stands each having a roll gap leveling device.

Background Art

[0002] When rolling a rolled material with a continuous rolling mill, the phenomenon that the rolled material deviates from the center position in the width direction of the rolling roll and moves in either the left or right (drive side and working side) direction is called snake-like movement. On the other hand, a rolled material having a curved shape in the width direction is called a camber. It is known that a large camber is likely to occur locally near the tip or the tail end of the rolled material. The camber remaining in the steel strip after rolling causes a winding deviation called telescoping in the steel strip coil after winding. The telescoping of the steel strip coil may lead to an accident during coil transportation. In addition, the large camber at the tip and tail end of the rolled material may collide with the side guides between the rolling stands or the side guide on the inlet side of the coiler, resulting in a threading trouble. When such troubles occur, accident handling, equipment repair work, etc. occur, and productivity decreases. Therefore, it is necessary to suppress the camber.

[0003] Here, the camber is the difference in the amount of reduction in the left and right in the rolling process, expressed as the difference in elongation in the rolling direction. The causes of the difference in the amount of reduction in the left and right include adjustment deviation of roll gap leveling, difference in rolling reaction force due to the temperature difference between the left and right of the rolled material, uneven wear of the rolling rolls, or the difference in the plate thickness of the base material between the left and right.

[0004] In order to suppress camber, it is necessary to appropriately adjust the left - right opening between the upper and lower rolling rolls using a roll gap leveling device. In order to correct local camber such as at the tip, it is necessary to accurately measure the camber shape at each position in the longitudinal direction of the rolled material. However, measuring the camber shape over the entire length of the rolled material is technically difficult, and many control methods using the measurement results of the amount of meandering have been proposed instead of the camber shape. Since the roughing mill can repeatedly perform measurement and adjustment of roll gap leveling, many proposals for control methods applied to the roughing mill have been made, but camber also occurs in the finishing mill. In particular, camber often remains in the portions corresponding to the vicinity of the tip and the tail end where there is no restraint of tension.

[0005] In Patent Document 1, in order to suppress the occurrence of telescoping of the steel strip coil, based on the amount of meandering detected by meandering detectors installed on the exit side and the entrance side of the final rolling stand, the roll gap leveling of the final rolling stand is controlled so that the amount of meandering falls within a predetermined range. The method described in Patent Document 1 is so - called feedback control based on the detected value of the amount of meandering. Also, in Patent Document 2, the length and amount of curvature of the camber are detected by a shape detector provided on the entrance side of the finishing mill, and based on the detected values, the leveling correction amount of the rolling stand of the finishing mill is set.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, the coiler amount detector on the outlet side of the finishing rolling mill is usually installed at a distance of about 15 m from the final rolling stand. In the feedback control as described in Patent Document 1, it is impossible to control the coiler amount and camber of the rolled material at a length of the rolled material tip within the distance.

[0008] Also, according to the method of adjusting the position of the roll gap leveling based on the camber detected on the inlet side of the finishing rolling mill as described in Patent Document 2, even if it is possible to reduce the camber created by the roughing mill, it is impossible to suppress the camber caused by factors (hardness) inherent in the finishing rolling mill, such as the adjustment deviation of the roll gap leveling of each rolling stand of the finishing rolling mill. Also, although the roll gap leveling of each rolling stand seems to be adjusted and maintained at a constant roll gap leveling position during rolling, simply adjusting the roll gap leveling position in this way cannot provide the same straightening effect over the entire length of the rolled material and correct the local bending at the tip, and thus cannot improve the yield.

[0009] The present disclosure has been made to solve the above-described problems, and an object thereof is to provide a camber control device for a continuous rolling mill that can reduce the camber of the tip of a rolled material and suppress the occurrence of telescoping in a steel strip coil when rolling the rolled material with a continuous rolling mill.

Means for Solving the Problems

[0010] The first aspect relates to a camber control device for a continuous rolling mill. The continuous rolling mill includes a plurality of rolling stands having roll gap leveling devices. The camber control device includes a snake amount detector that detects the amount of snake of the rolled material, a tip camber measurement unit that calculates a tip camber measurement value at the tip of the rolled material based on the amount of snake detected by the snake amount detector, a camber correction leveling calculation unit that calculates a camber correction leveling amount, which is the amount of roll gap leveling necessary to reduce the tip camber at each rolling stand, based on the tip camber measurement value calculated by the tip camber measurement unit, a tip leveling setting unit that sets a tip leveling correction amount and a tip leveling control length, which are set values for reducing the tip camber, for the roll gap leveling device of each rolling stand, and a roll gap leveling control unit that adjusts the roll gap leveling device to a position where the tip leveling correction amount is added before the rolled material enters each rolling stand, and adjusts the position of the roll gap leveling device so that the tip leveling correction amount gradually decreases after the rolling length at each rolling stand reaches the tip leveling control length.

[0011] In addition to the first aspect, the second aspect further has the following features. The snake amount detector is arranged on the outlet side of the final rolling stand. The camber correction leveling calculation unit calculates the camber correction leveling amount based on the tip camber measurement value on the outlet side of the final rolling stand. The camber control device further includes a tip leveling learning unit that learns and updates the tip leveling correction amount applied to the rolling of the subsequent rolled materials based on the camber correction leveling amount. The tip leveling setting unit sets the latest value updated by the tip leveling learning unit as the tip leveling correction amount.

[0012] In addition to the first aspect, the third aspect further has the following features. The snake amount detector includes a first snake amount detector disposed on the outlet side of the final rolling stand and at least one second snake amount detector disposed between any two rolling stands. The camber correction leveling calculation unit calculates the camber correction leveling amount based on the leading edge camber measurement value at the outlet side of the final rolling stand and the leading edge camber measurement value between the rolling stands for the rolling stand upstream of the second snake amount detector. The camber correction leveling calculation unit calculates the camber correction leveling amount based on the leading edge camber measurement value at the outlet side of the final rolling stand for the rolling stand downstream of the second snake amount detector. The camber control device further includes a leading edge leveling learning unit that learns and updates the leading edge leveling correction amount applied to the rolling of the subsequent rolled material based on the camber correction leveling amount. The leading edge leveling setting unit sets the latest value updated by the leading edge leveling learning unit as the leading edge leveling correction amount.

[0013] In addition to the first aspect, the fourth aspect further has the following features. At least one snake amount detector is disposed between any two rolling stands. After the measurement over the rolling length required for calculating the leading edge camber measurement value is completed by the snake amount detector, each process of the leading edge camber measurement unit, the camber correction leveling calculation unit, and the leading edge leveling setting unit is immediately executed. The camber correction leveling calculation unit calculates the camber correction leveling amount for each rolling stand downstream of the snake amount detector based on the leading edge camber measurement value in the snake amount detector. The leading edge leveling setting unit sets the leading edge leveling correction amount and the leading edge leveling control length for the roll gap leveling device of each rolling stand downstream of the snake amount detector in the rolling of the current rolled material based on the camber correction leveling amount.

Advantages of the Invention

[0014] According to the present disclosure, in a continuous rolling mill equipped with at least one meandering amount detector, it is possible to reduce the local camber at the tip of the rolled material and suppress the telescoping of the steel strip coil wound by the coiler. In addition, during threading of the tip, it is possible to avoid troubles in which the tip of the rolled material curved toward the side guide collides with the side guide.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted.

[0017] [Continuous Rolling Mill] FIG. 1 is a diagram showing a configuration example of a continuous rolling mill to which the camber control device according to the present disclosure is applied. The continuous rolling mill 1 is a multi-stage rolling mill including a plurality of rolling stands F1, F2, ···, Fn. n is a natural number of 2 or more. The rolled material M is steel or other metal material. The rolled material M is hot-rolled to a predetermined plate thickness while moving from the left side to the right side in the figure. The rolled material M rolled into a plate shape is wound by a winder (not shown) to form a steel strip coil.

[0018] Each rolling stand Fi (1 ≤ i ≤ n) includes two upper and lower work rolls Rw and two upper and lower backup rolls Rb respectively arranged on the outer sides in the vertical direction of the work roll Rw. A rolling reduction device (not shown) is provided on the working side and the driving side of the backup roll Rb respectively, and the gap between the upper and lower work rolls Rw can be adjusted. Each rolling stand Fi further includes a rolling reduction leveling device Vi (1 ≤ i ≤ n), which can adjust the parallelism of both the working side and the driving side, or one side of the upper and lower work rolls Rw by the rolling reduction device, and change the difference between the working side and the driving side of the gap between the upper and lower work rolls Rw. Note that the rolling reduction leveling device Vi makes the upper and lower work rolls Rw contact each other, and when the rolling reduction devices on the working side and the driving side are tightened by a certain amount, the position where the loads detected by the load cells on the working side and the driving side are substantially equal is set as the zero reference of the rolling reduction leveling device Vi.

[0019] The continuous rolling mill 1 has at least one camber amount detector Di between the stands of the rolling stands F1, F2, ···, Fn or on the outlet side of the final rolling stand. The camber amount detector Di includes a first camber amount detector Dn arranged on the outlet side of the final rolling stand Fn and a second camber amount detector D3 arranged between the stands of the rolling stands F3 and F4. Each camber amount detector Di (1 ≤ i ≤ n) is installed at a distance LDi downstream of the rolling stand Fi. The camber amount detector Di may be either an optical or a contact type detector, which detects the left and right end positions of the rolled material M and outputs the deviation of the center position of the rolled material M from the center position of the rolling mill, determined from the left and right end positions of the rolled material M, as the camber amount.

[0020] The continuous rolling mill 1 is provided with a setup device 2 and a camber control device 3. The setup device 2 outputs various setup values necessary for the camber control device 3, specifically, the plate thickness of the rolled material M, the influence coefficient, and the tip leveling control length of the final rolling stand Fn, etc. at each rolling stand Fi, to the camber control device 3 before the start of rolling of the rolled material.

[0021] Based on the setup values acquired from the setup device 2 and the snake amount detected by the snake amount detector Di, the camber control device 3 calculates the reduction leveling setting values for each rolling stand Fi and adjusts the reduction leveling device Vi.

[0022] Embodiment 1. Figure 2 is a block diagram showing the configuration of the camber control device 3 according to Embodiment 1. The camber control device 3 includes a tip camber measurement unit 31, a camber correction leveling calculation unit 32, a tip leveling learning unit 33, a tip leveling setting unit 34, and a reduction leveling control unit 35. Hereinafter, the functions constituting the camber control device 3 will be described in detail.

[0023] Before the start of rolling, the camber control device 3 executes the tip leveling setting unit 34. Based on the setup values of the next rolled material acquired from the setup device 2 and the learning values acquired from the tip leveling learning unit 33, the tip leveling setting unit 34 determines the "tip leveling correction amount" and the "tip leveling control length" for each rolling stand Fi. The tip leveling control length is the length of the tip of the rolled material for which the tip camber is to be controlled. The tip leveling control length L at the final rolling stand Fn CMB,N Any length can be set, for example, it is set within the range of 15 m to 20 m. The tip leveling control length L at each rolling stand Fi CMB,i As shown in the following formula (1), it is determined by the plate thickness ratio (h CMB,N / h i / h N ) of the outlet side plate thickness hi of each rolling stand Fi with respect to the tip leveling control length L at the final rolling stand Fn.

[0024]

Number

[0025] The tip leveling setting unit 34 determines the latest learned value obtained from the tip leveling learning unit 33 as the tip leveling correction amount. The tip leveling setting unit 34 sets the tip leveling correction amount and the tip leveling control length to the roll gap leveling control unit 35 at a specified timing before the rolled material M enters each rolling stand Fi.

[0026] The roll gap leveling control unit 35 has a tracking function for calculating the rolling length in each rolling stand Fi, and operates the roll gap leveling device Vi based on the tip leveling correction amount and the tip leveling control length set by the tip leveling setting unit 34.

[0027] Figure 3 is a diagram for explaining the operation of the roll gap leveling device Vi by the roll gap leveling control unit 35. When the tip leveling correction amount and the tip leveling control length are set by the tip leveling setting unit 34, the roll gap leveling device Vi is adjusted to the position obtained by adding the tip leveling correction amount. When the rolling distance of the rolling stand Fi reaches the tip leveling control length, the position of the roll gap leveling device Vi is adjusted so that the added tip leveling correction amount gradually decreases.

[0028] After the measurement of the tip of the rolled material at the snaking amount detector Dn on the outlet side of the final rolling stand Fn is completed, the camber control device 3 sequentially performs the processes of the tip camber measurement unit 31, the camber correction leveling calculation unit 32, and the tip leveling learning unit 33 as described below.

[0029] The tip camber measurement unit 31 is provided with snaking amount detectors D at each of the spaces between the rolling stands and on the outlet side of the final rolling stand Fn iIn this case, the amount of meandering at the tip of the rolled material is measured. Each amount of meandering is obtained by collecting the detected values during the period in which the tip of the rolled material passes through a length specified by the tip leveling control length after reaching the meandering amount detector Di. Next, the tip camber measurement unit 31 calculates the tip camber measurement value of the rolled material M using the measurement data of the amount of meandering. The size of the tip camber is defined as the average value of the curvature when the change in the amount of meandering near the tip of the rolled material is approximated by a curve. As one method for obtaining the curvature of the tip camber using the measured meandering amount data, a method can be used in which an approximate polynomial is obtained from the relationship obtained by plotting the measured meandering amount data with the measurement position on the X-axis and the amount of meandering on the Y-axis, and calculated by the method shown in the following formula (2). The following formula (2) gives the curvature for each measurement position. Therefore, when the approximate polynomial is of the third degree or higher, the average value of the curvatures calculated for each measurement position is calculated. When the approximate polynomial is of the second degree, a unique curvature is calculated, and the result becomes the average curvature.

[0030]

Number

[0031] The crown correction leveling calculation unit 32 calculates the correction amount of the roll gap leveling required to correct the head crown. FIG. 4 is a diagram for explaining the processing by the crown correction leveling calculation unit 32. First, the crown correction leveling calculation unit 32 determines the estimated value of the head crown at each rolling stand using the head crown measurement values at the inlet and outlet of the final rolling stand calculated by the head crown measurement unit 31. If there is no loop detector between any rolling stands, the estimated value of the head crown at each rolling stand is set to be the same as the head crown measurement value at the outlet of the final rolling stand Fn. If there is a loop detector between any rolling stands and the head crown measurement value can be obtained, the estimated value of the head crown at the rolling stand upstream of the loop detector is calculated by apportioning the head crown measurement value at the outlet of the final rolling stand and the head crown measurement value at the loop detector between rolling stands as shown in the following formula (3). The head crown at the rolling stand downstream of the loop detector is set to be equal to the head crown measurement value at the outlet of the final rolling stand.

[0032]

Number

[0033] Next, the crown correction leveling calculation unit 32 calculates the crown correction leveling amount for each rolling stand using the estimated value of the head crown at each rolling stand and the influence coefficient as shown in the following formula (4).

[0034]

Number

[0035] The tip leveling learning unit 33 updates the tip leveling correction amount for each rolling stand based on the camber correction leveling amount calculated by the camber correction leveling calculation unit 32 as shown in the following formula (5). "OLD value" is a value determined based on the results before the current rolled material, and is stored in a hierarchical table classified by conditions such as the steel type, size, heating furnace number, and rolling stand number of the rolled material M. The hierarchical table is stored in the memory 30c described later. "NEW value" is a value updated based on the results of the current rolled material, and the updated latest tip leveling correction amount is overwritten and stored in the hierarchical table.

[0036] [Number]

[0037] As described above, according to the present embodiment, by adaptively correcting the set value of the roll gap leveling device for all rolling stands based on the tip camber measurement value on the outlet side of the final rolling stand Fn and the tip camber measurement value at the intermediate rolling stand, the tip camber can be reduced.

[0038] Embodiment 2. FIG. 5 is a block diagram showing the configuration of the camber control device according to Embodiment 2. In the present embodiment, the tip camber measurement unit 31 is different from the first embodiment in that, immediately after the measurement of the meandering amount in the range of the material length given as the tip leveling control length of the tip of the rolled material by the meandering amount detector D3 between the rolling stands F3 and F4 is completed, the tip camber measurement value is calculated immediately. Immediately after the processing of the tip camber measurement unit 31 is completed, the processing of the camber correction leveling calculation unit 32 is performed.

[0039] FIG. 6 is a diagram for explaining the processing by the camber correction leveling calculation unit 32. The camber correction leveling calculation unit 32 determines the estimated value of the tip camber at each rolling stand on the downstream side of the snake amount detector to be equal to the measured value of the tip camber. Next, as shown in the above formula (4), the camber correction leveling calculation unit 32 calculates the camber correction leveling amount of each rolling stand on the downstream side of the snake amount detector using the estimated value of the tip camber and the influence coefficient. Immediately after the processing of the camber correction leveling calculation unit 32 is completed, the tip leveling setting unit 34 is implemented.

[0040] The tip leveling setting unit 34 determines the tip leveling correction amount and the tip leveling control length to be set for the roll gap leveling device of each rolling stand on the downstream side of the snake amount detector Di based on the camber correction leveling amount.

[0041] Similar to the first embodiment (see FIG. 3), the roll gap leveling control unit 35 operates the roll gap leveling device Vi of each rolling stand according to the tip leveling correction amount and the tip leveling control length set from the tip leveling setting unit 34.

[0042] As described above, according to the present embodiment, by measuring the tip camber while the tip of the rolled material passes through the continuous rolling mill 1 and adjusting the roll gap leveling of the remaining rolling stands, the tip camber of the rolled material M on the outlet side of the final rolling stand Fn can be reduced.

[0043] Although not limited to the specific structure of the camber control device 3 in the above-described Embodiments 1 and 2, it may be, for example, as follows. FIG. 7 is a diagram showing an example of the hardware configuration of a processing circuit included in the camber control device 3. The functions of the camber control device 3 can be realized by the processing circuit 30 shown in FIG. 7. This processing circuit 30 may be dedicated hardware 30a. This processing circuit may include a processor 30b and a memory 30c. This processing circuit may be partly formed as dedicated hardware 30a and further include a processor 30b and a memory 30c. The example of FIG. 7 is such that part of the processing circuit is formed as dedicated hardware 30a and the processing circuit also includes a processor 30b and a memory 30c.

[0044] At least part of the processing circuit may be at least one piece of dedicated hardware 30a. In this case, the processing circuit corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel-programmed processor, an ASIC, an FPGA, or a combination thereof.

[0045] The processing circuit may include at least one processor 30b and at least one memory 30c. In this case, each function of the camber control device 3 is realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in the memory 30c. The processor 30b reads and executes the programs stored in the memory 30c to realize the functions of each part.

[0046] The processor 30b is also called a CPU (Central Processing Unit), a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, or a DSP. The memory 30c corresponds to, for example, a non-volatile or volatile semiconductor memory such as a RAM, a ROM, a flash memory, an EPROM, or an EEPROM.

[0047] In this way, the processing circuit can implement each function of the camber control device 3 by hardware, software, firmware, or a combination thereof.

[0048] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and can be implemented with various modifications without departing from the spirit of the present invention. The configuration of the continuous rolling mill is not limited to the example shown in FIG. 1, and the present invention can be applied to continuous rolling mills with various modified configurations. Also, when referring to numbers such as the number, quantity, amount, range, etc. of each element in the above-described embodiments, unless specifically specified or clearly specified by the principle, the present invention is not limited to the mentioned number. Further, the structures and the like described in the above-described embodiments are not necessarily essential to the present invention, unless specifically specified or clearly specified by the principle.

Explanation of Reference Numerals

[0049] 1... Finishing rolling mill (continuous rolling mill), 3... Camber control device, Vi... Roll gap leveling device, Fi... Rolling stand, M... Rolled material, Di... Snaking amount detector, Dn... First snaking amount detector, D3... Second snaking amount detector, 31... Tip camber measurement unit, 32... Camber correction leveling calculation unit, 33... Tip leveling learning unit, 34... Tip leveling setting unit, 35... Roll gap leveling control unit

Claims

1. A camber control device for a continuous rolling mill, in the case where the continuous rolling mill includes a plurality of rolling stands having a roll gap leveling device, a snake amount detector for detecting the snake amount of the rolled material, a tip camber measurement unit that calculates a tip camber measurement value at the tip of the rolled material based on the snake amount detected by the snake amount detector, a camber correction leveling calculation unit that calculates a camber correction leveling amount, which is the roll gap leveling amount necessary to reduce the tip camber at each rolling stand, based on the tip camber measurement value calculated by the tip camber measurement unit, a tip leveling setting unit that sets a tip leveling correction amount, which is a set value for reducing the tip camber, and a tip leveling control length, which is the length of the tip of the rolled material for controlling the tip camber, for the roll gap leveling device of each rolling stand, before the rolled material enters each rolling stand, the roll gap leveling device is adjusted to a position where the tip leveling correction amount is added, and after the rolling length at each rolling stand reaches the tip leveling control length, the position of the roll gap leveling device is adjusted so that the tip leveling correction amount of the rolling stand gradually decreases, the snake amount detector is disposed on the outlet side of the final rolling stand, the camber correction leveling calculation unit uses the tip camber measurement value on the outlet side of the final rolling stand as the tip camber estimated value of each rolling stand, and calculates the camber correction leveling amount based on this tip camber estimated value and the influence coefficient of each rolling stand, the camber control device further includes a tip leveling learning unit that learns and updates the tip leveling correction amount applied to the rolling of the subsequent rolled materials based on the camber correction leveling amount, the tip leveling setting unit is characterized in that it sets the latest value updated by the tip leveling learning unit as the tip leveling correction amount. A camber control device for a continuous rolling mill.

2. A camber control device for a continuous rolling mill, in the case where the continuous rolling mill includes a plurality of rolling stands having a roll gap leveling device, a snake amount detector for detecting the snake amount of the rolled material, a tip camber measurement unit that calculates a tip camber measurement value at the tip of the rolled material based on the snake amount detected by the snake amount detector, a camber correction leveling calculation unit that calculates a camber correction leveling amount, which is the roll gap leveling amount necessary to reduce the tip camber at each rolling stand, based on the tip camber measurement value calculated by the tip camber measurement unit, a tip leveling setting unit that sets a tip leveling correction amount, which is a set value for reducing the tip camber, and a tip leveling control length, which is the length of the tip of the rolled material for controlling the tip camber, for the roll gap leveling device of each rolling stand, before the rolled material enters each rolling stand, the roll gap leveling device is adjusted to a position where the tip leveling correction amount is added, and after the rolling length at each rolling stand reaches the tip leveling control length, the position of the roll gap leveling device is adjusted so that the tip leveling correction amount of the rolling stand gradually decreases, and the snake amount detector includes a first snake amount detector disposed on the outlet side of the final rolling stand and at least one second snake amount detector disposed between any of the rolling stands, the camber correction leveling calculation unit, for the rolling stands upstream of the second snake amount detector, determines a tip camber estimated value based on the tip camber measurement value at the outlet side of the final rolling stand and the tip camber measurement value between the rolling stands, and calculates a camber correction leveling amount based on the tip camber estimated value and the influence coefficient of each rolling stand, Regarding the rolling stand downstream of the second snaking amount detector, the tip camber measurement value at the outlet side of the final rolling stand is used as the tip camber estimated value, and the camber correction leveling amount is calculated based on this tip camber estimated value and the influence coefficient of each rolling stand. It is provided with a tip leveling learning unit that learns and updates the tip leveling correction amount applied to the rolling of the subsequent rolled materials based on the camber correction leveling amount. The tip leveling setting unit is characterized in that it sets the latest value updated by the tip leveling learning unit as the tip leveling correction amount in the camber control device of the continuous rolling mill.

3. A camber control device for a continuous rolling mill, In the case where the continuous rolling mill includes a plurality of rolling stands having a roll gap leveling device, At least one snaking amount detector arranged between any two rolling stands for detecting the snaking amount of the rolled material, After the measurement over the rolling length required for calculating the tip camber measurement value is completed by the snaking amount detector, based on the snaking amount detected by the snaking amount detector, a tip camber measurement unit that immediately calculates the tip camber measurement value at the tip of the rolled material, Based on the tip camber measurement value calculated by the tip camber measurement unit, a camber correction leveling calculation unit that calculates the camber correction leveling amount, which is the amount of roll gap leveling required to reduce the tip camber at each rolling stand downstream of the snaking amount detector, For the roll gap leveling devices of each rolling stand downstream of the snaking amount detector, a tip leveling setting unit that sets the tip leveling correction amount, which is the set value for reducing the tip camber, and the tip leveling control length, which is the length of the tip of the rolled material for controlling the tip camber, Before the rolling material enters each rolling stand on the downstream side of the serpentine amount detector, the roll gap leveling device of the rolling stand is adjusted to a position where the tip leveling correction amount is added. After the rolling length in each rolling stand on the downstream side of the serpentine amount detector reaches the tip leveling control length, a roll gap leveling control unit that adjusts the position of the roll gap leveling device so that the tip leveling correction amount of the rolling stand gradually decreases. The camber correction leveling calculation unit uses the tip camber measurement value in the serpentine amount detector as the tip camber estimated value, and based on this tip camber estimated value and the influence coefficient of each rolling stand, calculates the camber correction leveling amount of each rolling stand on the downstream side of the serpentine amount detector. A camber control device for a continuous rolling mill characterized by the above.

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