JPS6390312A - Sheet width controller - Google Patents

Abstract

PURPOSE:To stabilize sheet thickness and width regardless of measurement noise and to improve accuracy by calculating the sheet width from stored load value at a front stage vertical rolling mill and horizontal rolling mill for the metallic material and the stored width value of a rolled sheet and subjecting the width at a rear stage vertical rolling mill to approximate value control. CONSTITUTION:The metallic material 1 is rolled by the front stage vertical rolling mill and horizontal rolling mill 4, 5 and is further rolled by the rear stage vertical rolling mill and horizontal rolling mill 2a, 3a. the width of the metallic material emitted from the vertical rolling mill 5 is detected by a width gage 9 and is stored in an inlet side width memory device 22a. The values detected by load meters 6, 7 of the rolling mills 4, 5 are stored in both rolling load memory devices 22b, 22c. The stored values are put into an inlet side width calculator 40 which in turn makes the approximate value control of the width at the rolling mill 2a by operating a vertical roll correction position calculator 23a and a vertical roll position controller 25. The abnormal width part is controlled by the approximate value, by which the thickness and width of the sheet are stably controlled with the high accuracy in spite of noise inclusion.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to an automatic plate width of a hot rolling mill that passes a metal material heated to a high temperature between rotating rolls to form a plate material of a predetermined width. This relates to a control device.

[Conventional technology]

FIG. 2 is a block configuration diagram showing a conventional sheet width control device disclosed in, for example, Japanese Patent Publication No. 50-24907. In the figure, 1 is a metal material, 2 is a vertical roll of a roughing mill, and 3
Horizontal roll of Fi rough rolling mill, 9.10 is plate width gauge, 22F
i board width pattern determination storage device, 23II'i vertical roll position calculation device, 25 vertical roll position control device, 26 setting device, 27 required board width calculation device before rolling, 28 learning device,
30 is a roll position measuring device, 32 is a required strip width pattern calculation device before rolling, 33 is a width correction amount calculation device, and 34 is a vertical roll jump amount calculation device.

Next, the operation will be explained. For the metal material 1, the target sheet width Bs at the outlet side of the horizontal rolls 3 of the roughing mill is set by the setting device 26. The required plate width pattern before rolling Bs is determined from 9, Bs by the required plate width pattern calculation device 32 before rolling.
o is calculated. On the other hand, a strip width meter 9 installed on the inlet side of the vertical rolls 20 of the rough rolling mill actually measures the strip width pattern B' before rolling and stores it in the strip width pattern determination storage device 22. From the difference between this measured value and the required plate width pattern Bao before rolling, the width correction amount calculation device 33 calculates ΔBn=B−Bso.
Calculate the width correction amount ΔBn. Once the width correction amount is determined, this correction amount △Bn and the plate thickness Bs set by the setting device 26
Then, the amount of jump of the vertical roll 2 is calculated as a function of the deformation resistance. Here, the deformation resistance is the material of metal material 1,
It is determined by temperature etc. The amount of jump of the vertical roll is the amount of movement of the vertical roll when the slab is caught in the vertical roll 2 from the set position before the slab is caught in the vertical roll 2 and rolled. This varies depending on the amount of wear on the bearings that support the shaft of the vertical roll 2, the amount of elastic deformation of the entire vertical roll device, etc.

When the vertical roll jump amount ΔS is calculated, the vertical roll position Bc is calculated by subtracting the jump amount ΔS from the pre-rolling required strip width pattern Bso as Bc=Bso−ΔS.

The corresponding vertical roll position Be calculated by the method described above is used at the timing when the part of the metal material 1 whose width before rolling is stored in the sheet width pattern determination storage device 22 is rolled by the vertical rolls 2. Then, the vertical roll position is controlled by the vertical roll position control device 25, and the target board width B8 is obtained over the entire length of the board.

[Problem that the invention seeks to solve]

Since the conventional strip width control device is configured as described above, the strip width pattern before rolling, which is actually measured by the strip width gauge 9 installed on the entry side of the vertical roll 2, is an important input for control. However, when actually measuring the board width using the photoelectric board width meter that is currently widely used, noise may occur as shown by the arrow in Figure 3 due to steam rising from the line and water spray coming from the descaler. are often mixed in. This noise on the actual measured value of the entrance side board width of the vertical roll 2 directly affects the position of the vertical roll 2, which is the manipulated variable, and has the problem of causing large local changes in the finished board width. .

This invention was made to solve the above-mentioned problems, and even if noise is mixed into the measured value of the width of the board on the entrance side of the vertical roll, the position of the vertical roll 2 can be set without adversely affecting the width of the finished product. The purpose of this study is to obtain a board width control device that uses the following methods.

[Means for solving problems]

The strip width control device according to the present invention calculates the actual rolling load value when the width is rolled down in the vertical rolling mill in the previous stage upstream of the vertical roll entry side strip width gage, and the actual rolling load value when the horizontal rolling is carried out in the horizontal rolling mill in the previous stage. The actual plate thickness is approximated by the plate thickness calculation device based on the calculated value, and based on the calculation result, the roll position of the subsequent vertical rolling mill is corrected by the vertical roll position control device.

[Effect]

The actual measured value of the entrance side strip width to the vertical rolls, which is the input signal for strip width control in this invention, is expressed as a simulated actual value using the rolling load for width reduction and the rolling load for horizontal reduction in the preceding rolling mill. This simulated actual measurement value replaces the abnormal portion of the above-mentioned actual measurement value with noise, and acts to control the position of the vertical roll.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is a metal material to be rolled, 2a is a rear vertical rolling mill which is the operating end for strip width control, 3a is a rear horizontal rolling mill, 4 is a front vertical rolling mill, and 5 is a front horizontal rolling mill. , 6 is a vertical rolling load cell that measures the unbalanced load in the vertical rolling mill 4 in the previous stage, 7 is a horizontal rolling load cell that measures the horizontal rolling load in the horizontal rolling mill 5 in the previous stage, and 9 is a vertical rolling mill in the latter stage. 2a is a board width meter installed on the entry side of the board, 22a is an entry side board width storage device that stores the actual measurement value of the board width on the entry side of the vertical rolling mill by the board width meter 9, and 22b is a width reduction at the vertical rolling mill 5 in the previous stage. a front-stage vertical rolling load storage device that stores the vertical rolling load measured by the vertical rolling load meter 6 at the time;
Similarly, 22c is a front horizontal rolling load storage device that stores the load of the front horizontal rolling, 23a is a calculation device for correcting the vertical roll position of the Fi vertical rolling mill 2a, 25 is a Fi vertical roll position control device, 40 is each storage device 22m, This is an inlet side plate width device that calculates the input side plate width of the rear vertical rolling mill used for control from the actual values of 22b and 22c.

Next, the operation will be explained.

When the metal material 1 is width-rolled by the vertical rolling mill 4 in the previous stage,
The width rolling load actually measured by the vertical rolling load meter 6 is stored in the first stage vertical rolling load storage device 22b.

Furthermore, when the product is subsequently horizontally rolled by the horizontal rolling mill 5 in the previous stage, the horizontal rolling load actually measured by the horizontal rolling load meter 7 is stored in the horizontal rolling load storage device 22cK in the previous stage. Incidentally, when each of the preceding rolling mills 4 and 5 is a reversible rolling mill and rolling is performed a plurality of times, the actual measurement value at the time of the final pass of rolling is stored. When the rolling in the preceding rolling mills 4 and 5 is completed, the metal material IFi is transported to the subsequent rolling mills 2a and 3a. At this time, the board width is actually measured by the board width gauge 9 and stored in the entry side board width storage device 22a.

Now, as mentioned above, the actual value of the sheet width is often contaminated with noise due to water spray, steam, etc. from the descaler. It may lead to Therefore, the following processing is performed in the entry side board width calculation device 40.

In general, fluctuations in the longitudinal direction of the sheet width after rolling a metal material in a rolling mill can be determined by fluctuations in the sheet width in the longitudinal direction of the material at the tsuba entering the rolling mill and temperature changes if the settings of the vertical rolling mill are not changed during rolling. Fluctuations are the cause. That is, each rolling mill 4 in the previous stage,
There is a strong correlation between the board width and temperature at the input side of the board 5 and the board width measured at the exit side, that is, the board width meter 9. Further, the width of the entrance plate of the vertical rolling mill 4 in the previous stage has a strong correlation with the vertical rolling load thereof. This is because, when the settings of the vertical rolling mill 4 are constant, changes in the vertical rolling load are mainly brought about by changes in the entrance plate width. Similarly, it can be said that the longitudinal temperature of the metal material 1 has a strong correlation with the rolling load of the horizontal rolling mill 5, since it is thought that the load change of the horizontal rolling mill is mainly caused by the temperature change in the longitudinal direction. After all, it is considered that the actual value of the strip width stored in the entry side strip width storage device 22aK can be expressed by the vertical rolling load and horizontal rolling load stored in each of the storage devices 22b and 22e, respectively.

Now, let FEi be the actual value of the pressure regulating load. Actual value of horizontal rolling load for FRi Wi is the actual value of board width shall be. Further, the subscript l indicates each storage device 22a, 22b.

22c represents the first actual value in the longitudinal direction. However, it is assumed that the first actual values of the vertical rolling load, the horizontal rolling load, and the plate width are measured values for the same portion of the metal material 1, taking into account the elongation in the longitudinal direction due to rolling.

Now, regarding the actual values obtained by sampling N pieces over the entire length in the longitudinal direction, Wl=ao+al・FEi+a2・FRl−(1
Thinking about 1. That is, a simulated plate width actually measured value Wif is created in which the plate width is expressed by a linear equation of vertical rolling load and horizontal rolling load. In order to determine this parameter a o - a 2 f,
For example, a(1""'a2 may be obtained by solving the equation using the method of least squares.

In formula (2), the symbol for the sum is the sum of N actual values of the plate width, excluding abnormal l (the number of such l is M).

The determination that the actual value is abnormal may be made, for example, based on the deviation from the average value, or may be determined based on the deviation from the (1-1)th actual value. In this way, the parameters a0 to a
2 f is determined, and Wi, which simulates the width of the inlet side of the vertical rolling mill 2a in the subsequent stage, is determined by equation (1). As a result, if the actual value Wt of the plate width is abnormal, it can be changed to Wt
Create a Wt replaced by , and use it as the input side plate width for control. The above calculations are performed by the entrance plate width calculation device 40.

As input of this input side plate width Wlt, the vertical roll correction position calculation device I 23 a calculates the vertical roll correction position for obtaining a desired plate width over the entire length of the metal material on the exit side of the horizontal rolling mill 3a in the subsequent stage. In the vertical roll position control device 25, the part of the metal material 1 stored in the entry side strip width storage device 22a and calculated by the entry side strip width calculation device 40 is adjusted in accordance with the timing of width rolling in the subsequent vertical rolling mill 2a. , controls the position of the vertical roll.

〔Effect of the invention〕

As described above, according to the present invention, the vertical rolling load and horizontal rolling load of each of the preceding stage rolling mills approximate the strip width at the entrance of the subsequent vertical rolling mill, and the abnormal portion of the actual measurement of the strip width is determined by the approximation value. Since the structure is configured such that the plate width can be replaced with the plate width, it is possible to control the thickness width with high accuracy even if the actual worksite environment is bad and noise is mixed into the plate width actual value.

[Brief explanation of the drawing]

The first factor is a block diagram showing a strip width control device according to an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional strip width control device, and FIG. 3 is noise mixed into the actual measurement value of the strip thickness. FIG. 1 is a metal material to be rolled, 2a is a vertical rolling mill in the latter stage, 3 &
is the rear horizontal rolling mill, 4 is the front vertical rolling mill, 5 is the front horizontal rolling mill, 6 is the vertical rolling load cell, 7 is the horizontal rolling load cell,
9 is a board width gauge, 22a is an entry side board width storage device, 22b is a front stage vertical rolling load storage device, 22cr/i front stage horizontal rolling load storage device, 23ati vertical roll correction position calculation device, 25 is a vertical roll position control device , 40 is an entry side plate width calculation device. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Patent applicant: Mitsubishi Machine Co., Ltd. Agent: Patent attorney 1) Hiroshi Sawa: (2 others) - Figure 2

Claims (1)

[Claims] A downstream vertical rolling mill and a horizontal rolling mill for metal materials, a plate thickness gauge installed on the entrance side of the downstream vertical rolling mill, and a preceding vertical rolling mill and horizontal rolling machine installed on the input side of the plate thickness gauge. Then, the actual plate width measured by the vertical rolling load meter and horizontal rolling load meter installed in the vertical rolling mill and horizontal rolling mill in the previous stage, and the plate thickness gauge mentioned above, is calculated by the horizontal rolling load meter and the vertical rolling load. a plate thickness calculation device that performs approximate calculations based on the horizontal rolling load and vertical rolling load that were actually measured by a meter, and corrects the actual plate thickness value using the approximate values; A strip width control device comprising a vertical roll position correction device for correcting the roll position of the vertical rolling mill in the latter stage.