JPH01271003A - Method for controlling camber of sheet stock - Google Patents

Abstract

PURPOSE:To accurately adjust a camber to a target value by obtaining operating information such as an elongation percentage of a sheet stock, etc., finding a camber of the stock based on the information, and controlling the camber by a control means to adjust the camber to a target value. CONSTITUTION:A camber calculating device 28 finds a longitudinal and a lateral cambers generated on a sheet stock 10 and calculates deviations dL, dC between a longitudinal and a lateral target cambers from a parameter setter 26 for camber calculation and respective calculated camber values. The deviation values are inputted to an automatic camber control arithmetic unit 30 to find a drafting position corrective amount S and a tension corrective value t of a movable auxiliary roll 20. The corrective amount S(S) and tensile corrective value t(S) are inputted to a cross controller 32; the S(S) and t(S) are adjusted and transferred to a drafting position controller 34 and a tension controller 36. The controller 34 controls a drafting position of the roll 20 and the controller 36 controls a torque of a tension reel 22 so as to control a tension of the stock 10 based on the transferred control signals.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for controlling warpage of a sheet material, and in particular, a method for controlling warp of a sheet material suitable for controlling a cold rolled steel sheet that is rolled or temper-rolled so that it has a target warpage. Regarding.

[Conventional technology]

In the process of manufacturing plate materials such as steel materials, shape quality is one of the quality control items of the plate materials. This shape quality includes the flatness of the plate material, and things related to this flatness include defects in flatness shape and warped shape. Examples of defects in the flatness shape include elongation of the ends of the plate material 10 in the width direction as shown in FIG.
As shown in B), there are cases in which the plate material 10 has partial undulations, such as medium elongation where the central portion of the plate material 10 is elongated. Further, the warped shape includes a warped shape in which the plate material 10 is warped in the rolling direction (longitudinal direction) as shown in FIG. There is a warped shape in which the number 10 is warped (1982, Thin Plate Manual published by the Japan Iron and Steel Institute). Warped shapes of flatness become a problem if they exceed the allowable range. For example, if warped tinplate material occurs, it can cause printing defects or sheet defects in the can manufacturing process. . However, since the warpage of the sheet material becomes latent due to the tension applied to the sheet material during rolling or temper rolling, it has traditionally been difficult to quantitatively detect warpage during rolling. Quantitative data on warpage itself could only be obtained experimentally. Therefore, the conventional method of measuring warpage is to cut out a sample plate from the plate material after rolling, and then, while the sample plate is suspended, a worker, etc., measures the warp direction as shown in Figure 3. The warpage value d for a unit length of was measured using a length meter or the like, and based on the measurement results, qualitative knowledge regarding warpage was obtained through operational experience. Then, in order to make the board material have a desired warpage, the warpage is controlled based on this qualitative knowledge.

[Problem B that the invention attempts to solve]

However, as mentioned above, the warpage qualitatively found through measurements by workers etc. does not necessarily mean that the sample board accurately reflects the warp of the actual board as a whole. Because it is something that can be determined, there is a problem with accuracy. Regarding the technology for measuring the warpage of sheet materials, in order to measure the warpage in the width direction under tension, a laser beam is reflected on the steel sheet and the reflected light is received by an image sensor.
A laser-marked line method for detecting warpage has been published (Tetsu to Hagane, Vol. 69, No. 5, 1983); however, this technique measures warpage under no tension. Therefore, it is not a technique that can measure warpage when tension is generated in the plate material, such as during rolling.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional problems, and
It is an object of the present invention to provide a method for controlling the warpage of a plate material, which can quantitatively grasp the warpage of the plate material during rolling and accurately control the warp of the plate material to a target value.

[Means to solve the problem]

In a method for controlling warp of a plate, the present invention obtains operational information such as the elongation rate, tension, and rolling load of the plate when rolling the plate under predetermined rolling conditions, and based on the rolling conditions and the obtained operational information. , determine the warpage of the plate material using a predetermined mathematical model, and based on the determined warp, calculate the predetermined warp I1.
The above object has been achieved by controlling the warpage of the plate material using 11 means so that the warpage is as desired.

[Operation and effects of the invention]

During rolling, tension is applied to the steel plate and warpage becomes latent, so it is difficult to directly measure warpage during rolling. Therefore, as a result of various studies, the inventors determined that the sheet material could be I decided to look for warpage. Next, the mathematical model will be explained. In this case, the warpage value d per unit length L in the warp direction shown in FIG. 3 above is used as the index value that quantitatively expresses the warpage of the plate material. Here, as a mathematical model for warpage, the mathematical model fN for calculating the longitudinal warpage dL of the plate material is expressed as the following equation (1):
Mathematical model fc for calculating warp dc in the width direction of the plate material
is shown in the following equation (2). dL=f L(h, W, SD, D, R, e, t. F, ΔC)...(1) d c=f c(h, W, SD, D, R, e, t
. F, ΔC) ... (2) However, h, W, SD, and D are the thickness of the plate to be rolled,
These are the plate width, steel type, and warpage evaluation value in the previous process. Also, R
is the diameter of the rolling roll, e is the measured elongation value, t is the measured tension value, f is the measured rolling load value, and ΔC is the operator's correction value based on sample measurement, etc. Based on these equations (1) and (2), the rolling conditions such as plate thickness, plate width, steel type, etc. and operational information actually measured during rolling (e.g., elongation, tension, rolling load) are calculated based on the plate material during rolling. It is possible to calculate the warpage in the longitudinal direction and the width direction of As described above, the warpages dL and dc obtained from equations (1) and (2) and the target values of warpage in the longitudinal direction and width direction of the plate material CIt- The difference ΔdL, Δdc from o, (lco) is calculated by the following formula (
3) and (4), and in order to eliminate this difference, use a predetermined warp control means, such as tension control using a tension reel as shown in FIG. Correct the warpage of the board so that it matches the target warpage. Δd L=d L−d ,, (3) Δd
c = d c d co = 14) As described above, the present invention makes it possible to control the warping of plate materials during rolling, which was conventionally controlled based on the measurement results after rolling and the experience of the operator. As a result, the excellent effect of significantly improving the quality of the plate material can be obtained. Note that when longitudinal warpage and width direction warpage are corrected, mutual interference usually occurs between them. If this mutual interference occurs, accurate warpage control cannot be guaranteed, so it is necessary to eliminate mutual control interference. On the other hand, the difference in warpage ΔdL, Δd. Each correction amount Δd expressed as a transfer function to correct
If L (S) and Δd c (S ) are considered as shown in the following equation (5), and the tension correction value Δt of the plate material and the position correction amount ΔS of the auxiliary roll reduction are determined from this equation (5), the plate material can be accurately adjusted. warpage can be controlled. ...(5) However, g+ t (S), Q 12 (S), Q
21 (S) and +122 (S) are matrix elements when expressing the correction value Δt and the correction amount ΔS as a transfer function. In this way, by using equation (5) or by other well-known methods of controlling longitudinal and widthwise warping while making them non-interfering, it is possible to simultaneously control warpage in the lengthwise and widthwise directions of the board. .

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. This embodiment is a warpage control system for controlling the warpage of a plate material 10 such as a steel plate that is rolled in a four-stage temper rolling mill as shown in FIG. As shown in the figure, the temper rolling mill includes upper and lower work rolls 1 for rolling the plate material lO by pressing it from above and below.
2A, 12B, upper and lower backup rolls 14A, 14B for applying rolling force to the plate material 10 via the work rolls 12A, 12B, a payoff reel 16 for unwinding the plate material 10, and a rolled plate material 10. A fixed auxiliary roll 18 is fixedly provided on the line to control the warpage of the roll, a movable auxiliary roll 20 whose rolling position is controlled, and the plate material 10 is wound in the exit direction of the movable auxiliary roll 20. A tension reel 22 for controlling the tension is provided. In addition, the reference numeral 24 in the figure indicates the plate material 1.
This is a guide roll for supporting 0. The warp control system controls the rolling position of the movable auxiliary roll 20 and the tension i! of the plate material by the tension reel 22!
1IIv4 to control warping of the plate material 10. As shown in FIG. 1, this system includes a warpage calculation parameter setter 26 for setting parameters used for calculating warpage and target values for warpage, and a warpage calculation parameter setter 26 for setting parameters used to calculate warpage and target values for warpage, and a A warpage calculation device 28 calculates warpage from operational information such as elongation, tension, and rolling load (hereinafter referred to as process data), and calculates the amount of warpage (warpage correction amount ΔdL) of the plate material 10 to be controlled from the calculated warpage.
A warp automatic control calculation device 30 for determining S), Δdc(S)), and a cross for controlling warpage in the longitudinal direction and warp in the width direction so that they do not interfere with each other based on the determined warp correction amount. A controller 32, a roll-down position control device 34 for controlling the roll-down position of the control movable auxiliary roll 20 based on control signals from the automatic warpage control calculation device 30 and the cross controller 32, and a roll-down position control device 34 for controlling the roll-down position of the control movable auxiliary roll 20 based on the control signals of the automatic warpage control calculation device 30 and the cross controller 32; A tension control device 36 is provided for controlling the tension of the plate material 10 on the exit side of the rolling mill by changing the torque of the rolling mill. The effects of the embodiment will be explained below. In the warpage control system for the plate material 10 shown in FIG.
In order to obtain Lo and dco, first, the warp currently occurring in the plate material 10 is calculated by the warp calculation device 28. That is, in the warp calculation device 28, the measured elongation rate e,
In addition to inputting process data such as the measured tension value t and the measured rolling load value F, the calculation parameters include the plate thickness h, plate width W, steel type SD, pre-process warpage evaluation value D, rolling roll diameter R, etc. Enter rolling conditions. These input data,
Based on these parameters, calculations are performed using the mathematical model of equations (1) and (2) above, and the warp dL in the longitudinal direction and the warp dc in the width direction of the plate material 10 during rolling are determined. Next, the target value dLo of warpage in the longitudinal direction and the width direction inputted from the warpage calculation parameter setting device 26, the deviation ΔdL between Ico and the calculated values dL and da of each warp,
Δda is calculated using equations (3) and (4) above. Deviations of warpage ΔdL, Δdc determined as above
is input to the automatic warpage control calculation device 30. In the calculation device 30, the reduction position correction amount ΔS of the movable auxiliary roll 20 and the tension correction value Δt to be corrected are calculated in advance, which are necessary to eliminate the warp deviation amounts ΔdL and Δda and bring the warp to the target value. It is calculated using equation (5). Then, the determined rolling position correction amount ΔS (S) and tension correction value Δt
(s) is input to the cross controller 32. The cross controller 32 adjusts the input reduction position correction amount ΔS (S) and tension correction value Δt(S) so as to simultaneously and independently control the warp in the longitudinal direction and the warp in the width direction of the plate material 10. It is transmitted to the lowering position control device 34 and the tension control device 36. Based on the transmitted control signal, the roll-down position control device 34 controls the roll-down position of the movable auxiliary roll 20, and the tension control device 36 controls the roll-down position of the tension reel 22.
The tension of the plate material 10 is controlled by controlling the torque of the plate material 10. In this way, since the cross controller 32 is used to independently control the warpage in the longitudinal direction and the width direction, there is no mutual interference in the correction of warp control, and the warp can be controlled independently and accurately at the same time. I can do it. As described above, it is possible to accurately control the warpage of the plate material in both the longitudinal and width directions during rolling, and it is possible to achieve a significant improvement in the quality of the plate material. In addition, in the above-mentioned example, the plate material to be rolled is exemplified as one undergoing leg rolling, but the type of rolling in which the present invention is carried out is not limited to temper rolling, and any other type of rolling may be used. The present invention can also be implemented in rolling, and warpage of the plate material can be controlled with high accuracy. That is, in the embodiment described above, the rolling position of the movable auxiliary roll as the warp I11# means is used simultaneously with the leg device 34 and the tension control device 36 that controls the tension on the exit side of the rolling mill by the tension reel 22 to quickly and accurately control the plate material. 10 warpage was controlled. However, the means for pressing the warpage M of the plate material 10 is not limited to using these devices at the same time, and any one of the control means may be used as appropriate depending on the operating conditions. The present invention is not limited to the device having such a configuration, and warpage control means having other configurations may also be used. Furthermore, the reduction position control device 3
4, only the rolling position of the movable auxiliary roll 20 is controlled, but the rolling position of the fixed auxiliary roll 18 may also be controllable to control the warp of the plate material.
In this case, the warpage can be controlled from above and below, resulting in improved responsiveness.

[Brief explanation of the drawing]

FIG. 1 is a roll arrangement diagram including a block diagram showing the overall configuration of a four-high skin pass rolling mill and warpage control system according to an embodiment of the present invention, and FIGS. 2(A) and (B) are plate material Perspective views showing examples of flatness and shape defects that occur in Figures 3 (A) and (B).
) is a perspective view showing an example of a warped shape of a plate material. 10... Plate material (steel plate, etc.), 12A, 12B... Upper and lower work rolls, 14A,
14. B...Top and bottom backup rolls, 18...
・Fixed auxiliary roll, 20... Movable auxiliary roll, 22... Tension reel, 26... Parameter setting device for warpage calculation, 28... Warp calculation device, 30... Warp automatic IIJ control calculation device 2... Cross controller, 34... Auxiliary roll reduction position control device, 36...
Tension control device.

Claims (1)

[Claims] (1) When rolling a plate material under predetermined rolling conditions, operational information such as the elongation rate, tension, and rolling load of the plate material is obtained, and based on the rolling conditions and the obtained operational information, a predetermined mathematical model is used. A method for controlling warpage of a plate material, characterized in that the warp of the plate material is determined, and based on the determined warp, the warp of the board material is controlled by a predetermined warp control means so that the warp becomes a target warpage.