JP2006110550A - Method and apparatus for controlling rolling - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that it is difficult to control the amount of edge drop to the amount of target edge drop while maintaining the surface quality because the amount of final edge drop is not detected until the rolling at the final time ends in the case a material to be rolled which becomes one product by using one rolling mill is rolled a plurality of times with the same rolling mill. <P>SOLUTION: The amount of target edge drop is set for each rolling of rolling which is performed a plurality of times, the operation for controlling the edge drop so that the surface quality is affected is regulated and the target shape of every rolling is corrected so as to reduce the range of the amount of edge drop where is uncontrollable by regulation as much as possible. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rolling control method and a rolling control device.

  Conventionally, there is a technique of rolling a material to be rolled using a rolling mill, rolling the rolled material again using the same rolling mill, and obtaining a product with a set plate thickness by repeating this. .

  On the other hand, in recent years, the accuracy of control in the vicinity of the end of the rolled product in the sheet width direction (hereinafter referred to as edge drop control) is required, and in the apparatus of the above technique, a sheet width direction thickness gauge is provided on the outlet side. Based on this measured value, a technique for correcting the roll shift position of the rolling mill has been devised. Such a technique is known, for example, in Japanese Patent Laid-Open No. 04-294808.

Japanese Patent Laid-Open No. 04-294808

  Since the edge drop of the material to be rolled is easy to control when the plate thickness is thick and soft, the tandem rolling mill is controlled by shifting the roll of the rolling mill installed on the entry side. The control result can be detected when the rolled material after the roll shift has reached the position of the exit edge drop detecting means, so that if the edge drop amount deviates from a preset target, the control is further performed by performing further control. Edge drop amount.

  However, as described above, when the work to obtain a predetermined plate thickness by rolling the same rolled material a plurality of times with the same rolling mill is performed, the final edge drop amount is reduced until the final rolling is completed. It is unknown. It is difficult to control by roll shifting when the material to be rolled is finally rolled because the material to be rolled many times is thin and hard. For this reason, it is necessary to control the sheet within a short number of times in a plurality of rolling operations in which the plate is thick and soft, but since the sheet is further rolled until it becomes the final product after controlling to a certain target edge drop value. There is a problem that the final edge drop value is different from the target edge drop value.

  Also, when rolling in the middle of multiple rounds that will be the final product and controlling the roll to the target edge drop, depending on the shift direction, the surface quality of the material to be rolled may be a problem. is there. The work roll is worn due to friction with the material to be rolled, but is particularly worn at the edge of the plate. For this reason, if the roll position that has been worn greatly because it was at the end of the plate until now enters the plate width of the material to be rolled due to roll shift, the surface is damaged, which causes a problem in surface quality.

  An object of the present invention is to provide a rolling control method or a rolling control apparatus capable of improving accuracy in edge drop control.

  In order to achieve the above object, in the present invention, the material to be rolled is rolled with a rolling roll (first rolling), and further, the material to be rolled again with the rolling roll is rolled (second rolling). For each of the first rolling to the second rolling, a target value related to the plate thickness in the vicinity of the end portion in the plate width direction was set. Each of the multiple rollings is referred to as a pass, the first rolling is one pass, the second is two passes, and so on, and the final rolling is referred to as the final pass.

  In order to achieve the above object, in the present invention, the material to be rolled is rolled with a rolling mill (first rolling), and the material to be rolled again with the same rolling mill is rolled (second rolling). Further, in the rolling method in which the material to be rolled in the second rolling is again rolled with the same rolling mill (third rolling), and this is repeated until the final rolling, from the first rolling to the final For each of the rolling operations, a target value related to the plate thickness in the vicinity of the end in the plate width direction was set.

  Preferably, it is configured to have a target edge drop setting unit for each pass that gives a database of edge drop amounts in each pass and an edge drop target value in each pass estimated from the results of similar rolled material that has been rolled in the past. To do.

  Preferably, it is configured to have a target edge drop correction means for each pass for correcting the target edge drop amount of each pass based on the rolling results and optimizing the target edge drop amount during the subsequent rolling of the material to be rolled. To do.

  Preferably, the apparatus includes a target edge drop correction unit that corrects the target edge drop amount set by the target edge drop setting unit for each path so that the target edge drop amount can be removed within a range in which the movement of the roll shift is not restricted.

  Preferably, it is configured to have a shift restricting means for restricting the movement of the roll shift, which is a means for correcting the edge drop from the viewpoint of maintaining the surface quality of the material to be rolled, according to the setting of the target edge drop correcting means. The deviation between the target edge drop amount and the edge drop amount measurement value set by using the above means is removed by edge drop control. At this time, restriction by the shift restricting means is applied in the shift direction of the roll.

  In the present invention, the control accuracy in the vicinity of the end in the plate width direction can be improved. In particular, it becomes possible to produce a material to be rolled excellent in surface quality.

  Hereinafter, the example of the present invention is described about the case where a material to be rolled is rolled a plurality of times using a single stand reverse rolling mill as shown in FIG.

  The single stand reverse rolling mill includes a rolling mill 1, a left tension reel 2 installed on the left side thereof, and a right tension reel 3 installed on the right side.

  The configuration of the rolling mill 1 will be described with reference to FIG.

From the axial direction, the upper and lower work rolls 111 and 112 (hereinafter, the upper and lower work rolls 111 and 112 are collectively referred to as the work roll 11), the upper and lower intermediate rolls 121,
122 (hereinafter, the upper and lower intermediate rolls 121 and 122 are collectively referred to as the intermediate roll 12) and upper and lower backup rolls 131 and 132 (hereinafter, the upper and lower backup rolls 131 and 132 are collectively referred to as the backup roll 13). . Upper and lower work rolls 111,
112 has a taper in the opposite position in the sheet width direction of the material to be rolled up and down, and is configured such that the edge of the sheet that can be subjected to edge drop control is upside down with respect to the material 15 to be rolled. Similarly, the upper and lower intermediate rolls 121 and 122 are also configured so that the plate ends that can be edge-dropped vertically are reversed.

  Returning to FIG. 1 again, the case where the material to be rolled 15 is rolled from the right side to the left side of the rolling mill will be described as an example. First, the coiled material 15 inserted into the right tension reel 3 is rolled by the rolling mill 1 and taken up by the left tension reel 2 (this is called the first pass). If the material 15 to be rolled that has been inserted into the right tension reel has been wound up to the left side, the material is rolled from the left tension reel 2 toward the right tension reel 3 and wound around the left tension reel 2. The rolled material is rolled again until it is wound up by the right tension reel 3 (this is called the second pass). When there is no longer any material to be rolled that has been wound around the left tension reel 2, the material is rolled again from the right tension reel 3 toward the left tension reel 2 (this is called the third pass). Each time the material to be rolled 15 is rolled by a rolling mill, the material to be rolled 15 becomes thinner, and a predetermined plate thickness can be obtained by repeating this rolling operation. The rolling from the last left or right tension reel to the right or left tension reel to obtain a predetermined plate thickness is called the final pass. The plate thickness of the material 15 to be rolled gradually decreases with each pass. In this embodiment, the material to be rolled 15 unwound from the right tension reel 3 is rolled by the rolling mill 1 and then wound by the left tension reel as the first pass, and subsequently rolled up to the fifth pass (= 5 passes). Consider the case where the eye is the final pass.

  The shift method of the tapered work roll 11 will be described with reference to FIG. 3 as an example of the definition of the edge drop and the control method thereof. The rolled material 15 after rolling does not have a constant plate thickness in the plate width direction, and the plate thickness largely decreases particularly near the plate end. This region is referred to as edge drop, and control is performed so as to reduce edge drop as much as possible from the viewpoint of improving product yield, and this is referred to as edge drop control. The edge drop amount is defined as an edge drop measurement point as an inner point (for example, 10 mm from the plate end) by a certain length from the plate end in the plate width direction, and the plate thickness at that position and the plate thickness direction center plate thickness (or , The thickness of the plate 100 mm from the plate edge may be used). Although there is another definition method, in the present embodiment, description will be made according to this method.

  As an example of means for controlling the amount of edge drop, as shown in FIG. 3 (b), an enlarged view of the work roll 111 in FIG. A case of shifting in the roll axis direction) will be described. At the end of the roll where the diameter of the roll is small, the force to crush the material to be rolled becomes small, so the plate thickness becomes thick. Using this, when the work roll 11 is shifted inward (in the center direction in the plate width direction), the plate thickness distribution becomes like a one-dot chain line and the edge drop amount decreases. On the other hand, when the work roll 11 is shifted outward (in the plate width direction plate end direction), the plate thickness distribution becomes like a two-dot chain line, and the edge drop amount increases.

Returning to FIG. 1, the outline of edge drop control will be described. In addition, after outline description, it demonstrates using FIGS. The target edge drop amount setting device 31 for each path sets a target edge drop amount E _n ′ corresponding to each path (n indicates the number of paths. For example, n = 1 for one path and n for two paths. = 2). On the other hand, the target edge drop amount correcting device 32 for each path sets a target edge drop correction value ΔE ₁ ′ _n for correcting the target edge drop amount E _n ′ based on learning of the past edge drop control. This value is input to each path edge drop amount setting device 31, and accordingly, the command value E _n ′ + ΔE ₁ ′ _n is output from the target edge drop amount setting device 31 for each path.

On the other hand, the target edge drop amount correction device 33 sets the target edge drop amount correction value ΔE ₂ ′ _n based on the detection output of the left edge drop detection device 4 (or the right edge drop detection device 5). The target edge drop amount correction value ΔE ₂ ′ _n is added by the adder 41 and output as the target edge drop amount E _n ′ + ΔE ₁ ′ _n + ΔE ₂ ′ _n .

The target edge drop amount E _n ′ + ΔE ₁ ′ _n + ΔE ₂ ′ _n and the edge drop amount detection value E detected by the left edge drop detection device 4 (or the right edge drop detection device 5) are subtracted from each other by the subtractor 42. , Edge drop deviation amount (E _n ′ + ΔE ₁ ′ _n + ΔE ₂ ′ _n ) −E is obtained. The edge drop control device 30 calculates the shift amount δ _n of the work roll 11 based on the deviation amount (E _n ′ + ΔE ₁ ′ _n + ΔE ₂ ′ _n ) −E.

On the other hand, the target edge drop amount correction device 33 outputs a shift permission / inhibition command for limiting the shift of the work roll 33. The shift restricting device 34 outputs the shift amount δ _n from the edge drop control device 30 as it is based on the shift permission / inhibition command output from the target edge drop amount correcting device 33 or restricts the shift amount device to the work roll shift device. 20 is output.

  The work roll shift device 20, the edge drop control device 30, the target edge drop amount correction device 33, the target edge drop amount setting device 31 for each pass, and the target edge drop amount correction device 32 for each pass are input by one computer. The software may be configured to operate as output software, and the devices constituting each group may operate as one computer by being divided into groups.

  The target edge drop amount setting device 31 for each path will be described.

FIG. 3 shows a target edge drop amount (final target edge drop amount) as a product on a material to be rolled in a single stand reverse rolling mill. The target edge drop amount E _n ′ is indicated by a one-dot chain line as an amount of deviation from the plate thickness direction center portion plate thickness. When the edge drop control is to be performed, the final target edge drop amount and the target edge drop amount E _n ′ for each path to achieve it are required as shown in FIG. A target edge drop amount E _n ′ is set by the target edge drop setting device 31 for each path.

Details of the target edge drop setting device 31 for each path will be described. As shown in FIG. 5, the target edge drop setting device 31 for each path includes a target edge drop amount database 311 and a database search device 312. In the target edge drop amount database 311, the material to be rolled is determined as products A, B,. . . As a target edge drop amount data, a table of target edge drop amounts in each pass (a target edge drop amount E _n ′ from the first pass to the fifth pass is stored) is created for each product. Store in advance. If the product type is given by the switch input from the operator of the rolling mill, the data in the target edge drop amount database 311 is searched by the database search device 312, and the target edge drop amount 333 (E) for each pass for the corresponding product type. _n ′) can be obtained.

  For example, for the product A, the target edge drop amount setting table 333 for the product A is selected, and target values for the first to fifth passes are selected.

  Next, the target edge drop amount correction device 32 for each path will be described.

As described above, since the edge drop control is more effective when the rolled material is thicker and softer, the case of edge drop in 1 pass and 2 passes is considered. If the material to be rolled has an edge drop amount for each pass similar to the target edge drop setting device 31 for each pass, the final target edge drop amount is obtained as shown in FIG. However, if the edge of the plate is softer than expected, the edge drop amount is large and not the final target edge drop amount. This is due to the material of the material to be rolled and the state of the work roll, but it may be the same when the material of the same product type is rolled next, so in this case the target edge drop amount for each pass Need to be corrected. The target edge drop correction device 32 for each path obtains a target edge drop amount correction amount ΔE ₁ ′ _n as a value for correcting the target edge drop amount E _n ′.

  As shown in FIG. 5, the target edge drop correction device 32 for each path includes a target edge drop correction amount calculation device 321 and a database search device 322.

In the target edge drop correction device 32 for each path, each path target edge drop amount necessary for obtaining the final target edge drop amount is obtained from the edge drop amount result (learning of the past edge drop control) of each path as the target edge. Based on this, the drop correction amount calculation device 321 calculates an edge drop amount correction amount ΔE ₁ ′ _n for correcting each target edge drop amount E _n ′. The database search device 322 searches the database to be corrected (for example, selects the target edge drop amount setting table 333 for product A), and corrects each path target edge drop amount in the target edge drop amount database 311 (target). The value in the edge drop amount database is rewritten to the value of target edge drop amount E _n ′ + edge drop correction amount ΔE ₁ ′ _n ).

  FIG. 6 shows an example of correcting the target edge drop amount for each path. Since edge drop control is performed only for the first pass and the second pass, the deviation between the final target edge drop amount and the actual edge drop amount is added to the target edge drop amounts for the first pass and the second pass. Since the third and fourth passes have no edge drop control, the target edge drop amount is corrected in consideration of the natural attenuation. By performing edge drop control so that the corrected target edge drop amount is obtained in the first pass and the second pass, the final target edge drop amount can be obtained in the fifth pass.

  Next, the target edge drop amount correction device 33 will be described. First, the concept of edge drop correction will be described, and then a specific configuration will be described.

  Until now, edge drop control has been limited to the first pass and the second pass. This is because the thicker and softer the plate is, the easier it is to control, but the control effect is small for the third to fifth passes, but the control effect by roll shift can be obtained. The problem with the surface quality is when the work roll portion worn at the end of the plate enters the width of the material to be rolled. Thereafter, edge drop control for shifting the work roll is performed to avoid a problem in surface quality.

  The target edge drop amount correction device 33 functions to perform edge drop control under the constraint that the outside shift of the work roll is possible even after the third pass. Since the edge drop amount increases by shifting the work roll to the outside, it is possible to increase the small edge drop amount. Therefore, if the target edge drop amount is set to be small, it is possible to cope with the case where the edge drop amount becomes large due to variations in material characteristics for each coil of the material to be rolled.

  Therefore, in the target edge drop correction device 33, as shown in FIG. 7A, the target edge drop amounts for the first pass and the second pass are set to be smaller (thick plate thickness).

That is, the edge drop correction amounts ΔE ₂ ′ ₁ and ΔE ₂ ′ ₂ are set to negative values.

The edge drop correction amount ΔE ₂ ′ _n is calculated according to the material of the material to be rolled.

When the material to be rolled is harder than expected and the edge plate thickness is thick (edge drop amount is small), as shown in FIG. 7B, edge drop correction amounts ΔE ₂ ′ ₃ , ΔE ₂ ′ By increasing ₄ , the edge drop control is performed to shift the work roll to the outside, and the plate thickness is reduced (edge drop amount is increased). Edge drop control is performed by the edge drop control device 30. The edge drop control device 30 outputs a work roll shift command using the edge drop amount results measured by the left edge drop detection device 4 and the right edge drop detection device 5. When rolling from the right tension reel 3 toward the left tension reel 2, the result of rolling by the rolling mill can be measured by the left edge drop detection device 4. To control edge drop. The work roll shift command from the edge drop control device 30 is regulated by the shift regulation device 34 and output to the work roll shift device 20, and the work roll shift is performed. In the shift restriction device 34, only the outer shift from the edge drop control device 30 is performed, and the inner shift in which the surface quality is deteriorated is prohibited.

  On the other hand, when the edge plate thickness is thin (edge drop amount is large), the edge drop correction amount is set to zero as shown in FIG. Leave it to. In this way, by correcting the target edge drop amount, correction can be made while maintaining the surface quality even if the actual edge drop amount actually deviates from the target edge drop amount for each pass to some extent.

  As described above, in this embodiment, a single repurse rolling mill that rolls the material to be rolled from the right tension reel 3 to the left tension reel 2 and then rolls from the left tension reel 2 to the right tension reel 3 with a single rolling mill. However, the present invention is also applicable to a case where rolling is performed a plurality of times by a one-way type rolling mill that repeats rolling from the left tension reel 2 to the right tension reel 3, for example.

  In addition to the feedback control performed using the edge drop amount record in the left edge drop detection device 4 during rolling from the right tension reel 3 to the left tension reel 2, the edge drop amount record in the right edge drop detection device 5 is used. Feedforward control can be performed.

  Further, this method can be applied even when the edge drop detection devices 4 and 5 are only on the right side or the left side.

  In addition, this method can roll not only a single rolling mill but also a tandem rolling mill in which a plurality of rolling mills are arranged in series, and the material to be rolled is rolled multiple times by the rolling mill. Applicable to the case.

The block diagram of an edge drop control apparatus. The block diagram of a rolling mill. Explanatory drawing of the control using the definition and edge shift of an edge drop. FIG. 5 is a relationship diagram between an actual edge drop amount and a target edge drop amount for each path. Explanatory drawing of the target edge drop amount for each path. The operation | movement figure of target edge drop amount correction | amendment for every path | pass. The operation | movement figure of target edge drop amount correction | amendment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 ... Work roll shift apparatus, 30 ... Edge drop control apparatus, 31 ... Target edge drop amount setting apparatus for every right path, 32 ... Each path target edge drop amount correction apparatus, 33 ... Target edge drop amount correction apparatus, 34 ... Shift regulation apparatus.

Claims (15)

  A method of rolling a material to be rolled with a rolling roll as a first rolling, and rolling the material to be rolled again with the rolling roll as a second rolling, the first rolling and the second rolling. A rolling control method for setting a target value related to a plate thickness in the vicinity of the end portion in the plate width direction for each, and controlling the rolling rolls so as to approach the respective target values.   The rolling control method according to claim 1, wherein past rolling information is stored, and the target value is obtained based on the stored information.   In claim 1, the target value is obtained by receiving an output from a detecting means for detecting a plate thickness in the vicinity of the end portion in the plate width direction of the material to be rolled or a plate thickness in the vicinity of the end portion in the plate width direction after being rolled. Rolling control method to be corrected.   The rolling control method according to claim 1, wherein the inward shift of the rolling roll is limited.   5. The rolling control method according to claim 1, wherein the rolling includes single stand reverse rolling.   6. The rolling control method according to claim 1, wherein the rolling includes one-way single stand rolling.   7. The rolling control method according to claim 1, wherein the rolling includes tandem rolling.   In the rolling control method for rolling a material to be rolled a plurality of times with the rolling mill and obtaining a product with a predetermined plate thickness using a rolling mill, the end in the sheet width direction which is a target in each rolling when rolling a plurality of times A rolling control method characterized in that control is performed by setting a target value related to a plate thickness in the vicinity.   The material to be rolled is rolled as a first rolling with a rolling mill, the material to be rolled with the first rolling again with the same rolling mill is rolled as a second rolling, and the second rolling is performed again with the same rolling mill. In the rolling control method in which the rolled material is rolled and this is repeated until the final rolling, the target value relating to the plate thickness in the vicinity of the end in the width direction of the plate is measured for each of the first rolling to the final rolling. A rolling control method configured to set   A first means for rolling the material to be rolled as a first rolling with a rolling roll, a second means for rolling the material to be rolled again with the rolling roll as a second rolling, and the first rolling And a means for setting a target value related to the plate thickness in the vicinity of the end in the sheet width direction for each of the second rollings, and a means for controlling the rolling rolls so as to approach the respective target values. Control device.   The rolling control device according to claim 10, further comprising storage means for storing past rolling information, and obtaining the target value based on the stored information.   The target value according to claim 10, receiving an output from a detection means for detecting a plate thickness in the vicinity of the end portion in the plate width direction of the material to be rolled or a plate thickness in the vicinity of the end portion in the plate width direction after being rolled. A rolling control device comprising means for correcting   11. The rolling control device according to claim 10, further comprising means for restricting the inward shift of the rolling roll.   In the rolling control device that uses a rolling mill to roll the material to be rolled a plurality of times with the rolling mill and obtains a product with a predetermined plate thickness, the end in the plate width direction that is the target in each rolling when rolling a plurality of times A rolling control apparatus that performs control by setting a target value related to a plate thickness in the vicinity. The material to be rolled is rolled as a first rolling by a rolling mill, the material to be rolled that has been first rolled again by the same rolling mill is rolled as a second rolling, and further the second rolling is performed again by the same rolling mill. In the rolling control apparatus that rolls the material to be rolled and repeats this until the final rolling, the target value related to the plate thickness in the vicinity of the end in the sheet width direction for each of the first rolling to the final rolling. A rolling control device configured to set

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