JPH03133510A - Rolling control device - Google Patents

Abstract

PURPOSE:To obtain a rolled stock of good plate thickness accuracy by improving the accuracy in the load prediction for a rolled stock of immediately after changing a work roll couple. CONSTITUTION:A corrected prediction load value Pi<m> for a rolled stock 12 is found by multiplying a prediction load value PiCAL and a load correction coefficient alphaiP for the rolled stock 12. A roll gap Si corresponding to the found correction prediction load value Pi<m> is calculated and outputted to a roll gap setting means 6 and so the state of the outer peripheral face of the work roll couple of immediately after changing the work roll couple of a rolling mill F1 can be expressed quantitatively and also the accuracy in the load prediction for the rolled stock of immediately after changing the work roll is improved by modelling by including the transient state as well from the state of mill scale not being formed on the outer peripheral face of the roll couple of immedi ately after changing the work roll couple up to the steady state of mill scale being formed uniformly on the outer peripheral face of the work roll couple. Consequently the rolled stack of good plate thickness accuracy can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention generally relates to a rolling control device, and more particularly to a rolling control device suitable for hot rolling of rolled materials such as steel or non-ferrous metal materials.

(Prior art) In general, in hot strip rolling in which rolled materials such as steel are rolled in a heated state, work rolls (also called work rolls) that constitute a rolling mill are used. One cycle is defined as the period from the time a new item is replaced until the time it is replaced with a new item. And in this one cycle,
A lot organization and a coffin schedule, which will be described later, are established, and the rolled material is subjected to hot strip rolling based on these lot organization and coffin schedule. In the above-mentioned lot organization, rolled materials of the same target thickness, width, and steel type (hardness) are
A collection of about 0 (or 20 in some cases) is set as 10 points. In addition, the above-mentioned coffin schedule is, for example, a rolling mill other than a mill with a special structure such as a work roll shift mill (i.e., a rolling mill), in which the wear of the work and rolls due to the implementation of the rolling process is
This is used to prevent deterioration of the quality of the rolled material, such as damage to the rolled material. FIG. 3 shows an example of the above-mentioned coffin schedule. In FIG. 3, section A is a rolling process in which a black crust (i.e., an oxide film) is almost evenly formed on the outer circumferential surface of a pair of work rolls. On the other hand, section B shows the steady state of the rolling process after the skin has been formed approximately uniformly on the outer circumferential surface of the pair of work rolls.

The above-mentioned section A also shows the rolling process of several coils (the "coil" here refers to the rolled material) immediately after the pair of work rolls is replaced with a new one. The rolling of these several coils was carried out in such a way that the condition of the outer peripheral surface of the work roll pair immediately after being replaced was such that suitable rolling could be carried out in the steady state of the rolling process (i.e., the black crust was approximately evenly distributed on the outer peripheral surface of the work roll pair). Therefore, these few coils are also referred to as "leveling material". Therefore, in the above-mentioned steady state of the rolling process, a black crust can be formed approximately evenly on the outer circumferential surface of the work roll pair on these several coils called "leveling material", and this makes it possible to form a black crust on the outer peripheral surface of the work roll pair during the steady state of the rolling process described above. Generally, materials and dimensions are selected that allow stable rolling with fewer problems.

Although the above-mentioned several coils are called "leveling materials," the improvement in the thickness accuracy of these several coils during the transient state of the rolling process is due to the rolling process shown in section B in Figure 3. It cannot be ignored and is extremely important in order to achieve good and stable rolling in the steady state of the process. Therefore, in the setting calculations necessary to roll several coils of the "conditioning material", short-term (from one coil to the next) learning is required in adaptive control when replacing a pair of work rolls. Countermeasures have been taken, such as clearing the term to the initial value, or using a separate long-term (from one loft to the next lot) learning term for several coils immediately after replacing the work roll pair. There is.

(Problem to be Solved by the Invention) Conventionally, the method of holding and classifying the learning terms in the adaptive control used to perform the above-mentioned setting calculations has been limited to general materials that are not "conditioned materials" in the steady state of the rolling process. By adopting a different method of holding and classifying the learning items from those used when rolling coil materials in general, Since we were trying to improve the plate thickness accuracy of the coil material immediately after the work roll was replaced, which is the "breaking-in material," for example, the predicted load value of the first coil immediately after the work roll was replaced and this first coil. If a large difference occurs between the actual load value and the thickness of the first coil deviates significantly from the target thickness value,
Along with this, there is a problem in that the thickness of the next second coil also deviates significantly from the target thickness value again. Therefore, the above method cannot be said to be an effective countermeasure.

The reason why it is difficult to say that the above method is an effective countermeasure is that it does not physically take into account the factors that cause the actual load value on the coil immediately after the work roll is replaced to not match the predicted load value on the coil. No black scale (i.e., oxide film) is formed on the outer circumferential surface of the work roll pair immediately after replacement, and as a result, sticking and frictional problems occur at the interface between the work roll pair and the plate (i.e., the rolled material). I'm in such a state
It is thought that this increases the actual load value for the coil. When the actual load value for the coil increases in this manner, the predicted load for the coil deviates, thereby deteriorating the accuracy of the plate thickness of the coil.

In order to eliminate such problems, as the first few coils are rolled immediately after the work roll pair is replaced as a "leveling material", a black crust is gradually generated on the outer peripheral surface of the work roll pair. We derived a method (model) that can express the transient state in which the actual load value on the coil decreases due to the generation of this black crust and settles to a steady state in the rolling process, and based on this derived method (model), All that is required is to correct the pre-71-11 load on the coil.

However, in reality, it is quite difficult to quantitatively express the state of the outer circumferential surface of the work roll pair immediately after the work roll pair is replaced, and to model this including the transient situation of the outer circumferential surface of the work roll pair. It would be better if the problem could be solved using adaptive control expedients, but in reality, adaptive control expedients are insufficient.

As is clear from the above content, in the conventional method,
The biggest problem lies in the lack of success in modeling to physically accurately represent the rolling state immediately after work roll replacement.

Therefore, the present invention has been made to solve the above problems, and its purpose is to improve the accuracy of the loader nj for the coil immediately after replacing the work roll, and thereby
i. It is an object of the present invention to provide a rolling control device that can obtain a rolled material with good plate thickness accuracy.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, a first aspect of the present invention provides a strip rolling mill each provided with a plurality of stands to perform hot strip rolling on a given rolled material. The rolling control device includes a roll gap setting means for setting a roll gap defined by a pair of work rolls of each of the rolling mills, and input and output thickness data Hi of the rolling material in the rolling mill given from the outside. Thickness value hi Day 1 In the evening, the rotational speed value of the work roll pair Rj data, the material temperature value Ti data of the rolled material and the rolled material] Predicted load CA for one year of rolling based on the material information m of the rolled material
Predicted load value calculating means for calculating and outputting L heavy chain PiCAL, and roughness value R of the work roll pair given from the outside.
a1 data, number N of rolled material in a state where no oxide film is formed on the outer circumferential surface of the work roll pair after replacing the work roll pair, data, and the T
means for determining and outputting a corrected predicted load value Pi for the rolled material by multiplying the front handle AL by a load correction coefficient for correcting the measured load chain P based on the f data; calculating the roll gap value S1 by calculating the roll gap value Si;
The configuration is equipped with the following.

Moreover, in order to achieve the above object, the second invention of the present invention includes:
In a rolling control device for controlling each strip rolling mill provided with a plurality of stands in order to perform hot strip rolling on a given rolled material, a roll gap defined by a pair of work rolls of each of the rolling mills is set. A roll gap setting means, input thickness value H1 data, and output thickness value hi of the rolled material in the rolling mill given from the outside.
data, rotational speed value of the pair of work rolls, Rai data, material temperature value T1 data of the rolled material, and material information m of the rolled material R'i data of the rolled material, which is determined and outputted as a deformation resistance value. Operation 1 Calculation means, the H1 data given from the outside, and the h
1 data and the roll radius R data of the work roll pair, a contact arc length value hi between the work roll pair and the rolled material is determined and output]; The roughness value Rai data, the Hi data, the previous al
hi data, Rai data, Ti data 1
1 1 and the above L
' Based on the data, find the rolling force function Qm, 1
a rolling force function calculation means for outputting the R′i data, the contact arc length value hi, and the rolling force function +11;
1Qm, and means for calculating and outputting a corrected predicted load value P〒 for the rolled material by multiplying the board width B of the rolled material given from the outside by 1Qm, and the corrected r-measured load value A roll gap value S corresponding to pm was calculated, and the roll gear value Si was calculated to obtain the roll gap calculation means.

(Function) According to the first aspect of the present invention described above, the predicted load value PC for the rolled material determined by the predicted load value calculation means
AL is the formula used to determine this predicted load value P9AL (for example, pressure F force function Q
1 etc.) is a formula in which various coefficients are adjusted for rolled material in a steady state, not a conditioned material. ) does not represent.

On the other hand, the load correction coefficient α obtained by the load correction coefficient calculation means is obtained by taking into account the amount, type, density, etc. of the oxide film (i.e., black scale) attached to the outer peripheral surface of the work roll pair. Therefore, this load correction coefficient α,
is naturally determined in consideration of the state of the outer circumferential surface of the work roll pair immediately after the work roll pair is replaced. Therefore, the load value P to be output after calculating CAL, and the load correction coefficient α?
The corrected P7111I load value tp CAL Pl for the rolled material obtained from Therefore, it is possible to accurately predict the load on the rolled material immediately after the work roll pair is replaced, and to obtain a rolled material with good plate thickness accuracy.

Further, according to the second aspect of the present invention described above, the R'i data, the contact arc length value hi, and the externally given 1111
1 data of the plate width B of the rolled material, and further the roughness value R of the pair of work rolls given from the outside, data, H9at 1 data, h, data, R data, Ti data and 1j
1 and the rolling force function Q obtained based on the hi data.

l
Since the modifier 41 load value P for the rolled material is determined by multiplying by pl, the load on the rolled material immediately after the work roll is replaced can be accurately calculated as in the first invention. It is possible to predict and obtain rolled material with good plate thickness accuracy.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a rolling control device according to an embodiment of the present invention.

A rolling control device according to an embodiment of the present invention controls rolling mills F and -FN of N stands provided for hot strip rolling. That is, the rolling control device according to this embodiment controls the rolling mills F1 to Fo of each stand.
(In Fig. 1, only the i-th strip rolling mill F is shown for convenience of illustration.) Including the gap setting device 6 provided for each strip rolling mill F, the gap calculation device 5, the multiplier 4, and the pren1 load calculation device. 2 and a correction formula calculator 3, and one host computer 1 that outputs various data to the predicted load calculator 2 and the correction formula calculator 3 provided for each stand.

Each of the rolling mills F1 to Fn has an inter-way configuration, and as is clear with reference to the mouth strip rolling mill F shown in FIG. 1, they are arranged facing each other in the vertical direction. The pair of work rolls 11a, 11.llb are used to support the load applied to the rolled material 12 by the pair of work rolls 11a, llb. It is equipped with backup rolls 13a, 13b, etc. for backing up b. Gap setting device 6
According to the role gap information given externally,
The roll gap defined by the work rolls lla, llb is variably adjusted.

The host computer 1 determines the input thickness value H1, the output thickness value 3, and the roll speed (work roll 11a) of the rolled material 12 in the first strip rolling mill F1 based on a preset program and various data.

11b (rotational speed) value, VR5, material temperature (i.e., temperature of the rolled material 12)) value Ti, and material information (here, "material" refers to the material of the rolled material 12) m are determined by arithmetic processing, Each of these calculated values is output to a load calculator 2 that calculates and outputs the calculated values. The host computer 1 also controls the work rolls in the tffi strip rolling mill F.
Roughness value Rai data of b, rolling number NT data of the rolled material 12 in a state where no black crust is generated on the outer peripheral surface of the pair of work rolls immediately after replacement of the work rolls are determined by arithmetic processing, These determined values and the Ti data determined by the arithmetic processing are outputted to the modified computing unit 3.

The predicted load calculator 2 calculates the input thickness @H1, the output thickness value 1, and the material temperature 1 of the rolled material 12 in the first strip rolling mill F, which are output from the host computer 1.
1 value T, roll speed value vI? 1. After receiving the material information m,
■ Based on each of these pieces of information, the predicted 6J weight value P of rolled material 12 is
Calculate CAL, and output the calculated predicted load value p CAL.

The modified formula calculator 3 uses the 1 output from the host computer 1.
Work roll 11a in strip rolling mill F
, 1.1b roughness value Rai data, 1 rolling number NT data of the rolled material 12 in a state where no black crust is generated on the outer peripheral surface of the work roll pair immediately after work rolls lla and llb are replaced, the above T1 Upon receiving the data, the load value p is calculated and output based on each of these data.The load correction coefficient α? for correcting the CAL is calculated. Find the load correction coefficient α? It is designed to output .

A multiplier 4 receives the predicted load value PCAL outputted from the load calculation unit 2 which calculates and outputs it, and the load correction coefficient α2 outputted from the correction formula calculation unit 3, and calculates the predicted load value PCAL.
- Predicted load value P, recorded weight correction coefficient α? Multiply by 1

1, the corrected predicted load p on the rolled material 12 is
m is calculated, and this calculated load correction coefficient α? It is designed to output 1.

The gap calculator 5 calculates the roll 1 gap S to be set based on the corrected predicted load pm output from the multiplier 4, and calculates the calculated roll gear knob S,
By controlling the gap setter 6 based on the value of the work roll 1 in the first strip rolling mill F,
．． 1a, 11. The roll gap defined by b is set at S9. After the roll gap is set to the Sl, hot strip rolling of the rolled material 12 is performed.

Next, the operation of the rolling control device having the above configuration will be explained.

In the above (114 formation), the predicted load value p C for the rolled material 12 obtained by the predicted load calculator 2 described above
Generally, the value of AL can be expressed as follows, if the tension of the rolled material 12 is ignored. Here, K, [kg-ma
-2]+111 is the deformation resistance (hardness of the material) of the material constituting the rolled material 12, L, [:mm:l is the projected arc length of contact between the rolled material 12 and the pair of workpiece holes 11a and llb , B (mm)
is the plate width of the rolled material 12, Q, (dimension number 1) is the number of rolling edges.Here, the unit of the load value p CAL calculated and output is given by [TOM].

The rolling force function Q,1 is a formula expressing the rolling state h
i In the case of hot strip rolling according to the present invention, the equation of Sims (Slms) etc. is often used, but in any case, the equation of the rolling force function Q is: 1 The outer peripheral surface of the work rolls lla, llb This formula is effective when rolling is performed continuously in a steady state of the rolling process (as shown in section B in FIG. 3) where black crust is generated on the top. Therefore, the formula is not configured to correspond to the state of the outer circumferential surface immediately after the replacement of work rolls lla and llb (that is, a transitional situation in the rolling process), but the work roll 11a.

Good load pre-C1 for several coils (transient state of rolling process shown in section A in Fig. 3) immediately after replacement of 11b.
It cannot be said that it gives accuracy. Therefore, the upper computer 1
The work roll 11a in the i-th strip rolling mill F1 outputted from the i-th strip rolling mill F1.

Roughness value R of 11b, data, number N□ of rolled material 12 in a state where no black crust is generated on the outer circumferential surface of the work roll pair immediately after work roll 11a11 1 l b replacement data, material temperature value Ti The data is read into the correction formula calculator 3, and the load correction coefficient α? Calculate. The calculation of the load correction coefficient α2 by the correction formula calculator 3 is performed using, for example, equation (2) described below.

Here, Z, [no dimension] is the learning term up to the time of replacing the previous work rolls lla and llb, and a [μml] is the initial roll roughness value RaiCμm
], b, CK) are the coefficients of material temperature l T CH3, nR''T are the indexes for the initial roll roughness R, material temperature Ti, respectively.
l No dimensions], N [no dimensions],
Until the outer peripheral surfaces of work rolls lla and llb reach a steady state immediately after replacement (i.e., work rolls lla and llb
, is the number of coils during the period from a state in which the melasma does not form a bone tube at all to a state in which the melasma is almost completely attached to the outer peripheral surface of the tube (transient state). The number of coils is usually 3~
Although the number is approximately 5, it is also possible to use different numerical values for each type of steel, for example. In addition, as already explained, NT [no dimension] is the number of rolled materials 12 in a state where no black crust is generated on the outer circumferential surface of the pair of work rolls immediately after the work rolls lla and 'llb are replaced. Ah, between this N and the above N, the relationship NT≦Nc or T C holds true.

Generally, the value of hiNT or N is a number somewhat larger than 1 determined by the modified formula calculator 3. As the value of α? -Equation 1 converges to (2,)%. As the value of N changes to approach the value of Nc, the condition of the outer peripheral surfaces of the work rolls lla and 11b gradually changes to the steady state of the rolling process (Fig. 3, ) as shown in section B) and go <
(ap-1).

Furthermore, the expected load correction coefficient α? output from the load calculator 2 which calculates and outputs ? and is read into the multiplier 4,
In the multiplier 4, the read p CAL and α? The corrected predicted load calculation is performed by multiplying by the equation (3) described below.

The multiplier 4 executes the calculation shown in equation (3) above to obtain the hi work roll 11a.

Immediately after the replacement of coil 11b, the accuracy of predicting the load on the coil (i.e., rolling) 12) is clearly improved. That is, in the load prediction calculation, the work rolls lla, l
This is because it is equivalent to considering the state of the outer circumferential surface of the work rolls lla and 1.1b immediately after the replacement of the work rolls lb.

The value of the corrected predicted load PiCAL obtained by the multiplier 4 is read into the gap calculator 5, and the gap calculator 5 calculates the roll gap S to be set based on the read corrected predicted load value pif+.
Have them count by 1. Based on the roll gap S1 determined by the gap calculator 5, the gap setting device 6 sets the roll gap defined by the work rolls lla and llb in the i-th strip rolling mill Fi to the above S1,
Hot strip rolling is then carried out.

The reason why the correction calculation is performed by the multiplier 4, etc. described above is that it is obvious that in the range of NT≦Nc.If hiN1-No, the setting calculation for the next rolled material 12 is performed using Zol as the initial learning term, and then Thereafter, short-term learning is repeated in the usual manner, and the above-mentioned setting calculations are performed.

In this embodiment, the load correction coefficient α? When calculating, equation (2) is used, but this does not mean that the load correction coefficient αp is calculated only by equation (2). Therefore, the correction formula is not limited to (2) above. For example, the same effect as in this example can be obtained by creating an experimental formula by identifying parameters from various performance data and using this experimental formula. That's what you get.

As explained above, according to an embodiment according to the present invention,
Compared to the case of using a rolling control device according to the prior art, the accuracy is better and a product with a stable plate thickness can be obtained. Here, differences in effect between an embodiment according to the present invention and the prior art will be explained with reference to FIG.

Fig. 4 shows the actual plate thickness value of the rolled material 12 at the tip end thickness deviation Δh stand (the number of rolled materials 12).
FIG. In Figure 4, -・-
indicates the result of the plate thickness deviation Δh of the rolled material 12 according to the conventional method, and --Δ-- is a symbol indicating the effect according to an embodiment of the present invention.

As is clear from FIG. 4, in general, the rolling CT load P ((CTON): actual measured value) immediately after the replacement of the work rolls 1.1a and 1-1b is different from the normal predicted value pCAL. It tends to be higher than that. Tsumahi
When the roll gap defined by work rolls lla and llb is set based on p CAL, the thickness hA0T of the rolled material 12 is learned using the direct cutting learning term ZBP in which work rolls lla and llb are replaced if it becomes thicker than the target value. Therefore, the plate thickness h of the rolled material 12 of the two-mouth rolled material is
ACT becomes thinner. Thereafter, the plate thickness may become unstable during rolling (a) over several coils.

On the other hand, in an embodiment according to the present invention, when predicting the load on the single-port coil immediately after the work rolls lla and 11b are replaced, the correction 1EllR number, α? Is α?
〉1 and hip ACT≧P〒 is obtained.

1 1]
Furthermore, after the work rolls lla and llb are replaced, for the second wood coil (rolling mill 12), as a result of the first wood rolling, the work rolls lla and 11b are
Actual rolling load ACT due to black scale attached to the outer peripheral surface of
In order to follow p(2)P, α, (N-2 grain +
+T, and good plate thickness accuracy can be obtained. Thereafter, load prediction calculations are performed using the formula αp(NT)≧1 up to N, -No (No: number of rolling mills 12 in an unsteady state), and as a result, good plate thickness accuracy can be continuously obtained. It will be done.

Furthermore, N after one exchange of work rolls lla, llb. Up to this point, the load deviation for Nc is learned at the timing when the rolling of the rolled material 12 progresses in an unsteady state, and the Zoi
When replacing the work rolls 1.1a and llb next time, the work rolls 11. After replacing a and llb, the effect of hi learning becomes clearer by using it for load prediction calculation of the rolled material 12 with the first grain.

FIG. 2 is a block diagram showing the configuration of a rolling control device according to another embodiment of the present invention.

A rolling control device according to another embodiment of the present invention, like the rolling control device according to the previous embodiment, controls an N-stand rolling mill provided for hot strip rolling. In FIG. 2, the host computer 1 calculates the thickness value Hl of the rolled material 12 in the i-th strip rolling mill F, and the output thickness value of the rolled material 12 in the i-th strip rolling mill F, based on the preset program and various data. h1, the material temperature value T+ of the rolled material 12, the rotational speed value VR1 of the work rolls lla and llb, and the material information m are determined by arithmetic processing, and these six determined values are output to the deformation resistance calculator 7. The host computer 1 also calculates the roll radius R1 of the work rolls 11a and Ilb by arithmetic processing, and connects this calculated value with the Hi, h and data obtained by the arithmetic processing to a touch arc length calculator. Output to 8. The host computer 1 also determines the thickness B of the rolled material 12 through arithmetic processing, and outputs this determined value to the multiplier 10.

The host computer 1 further includes a work role 11a.

1, the roughness R of 1b is determined, and the obtained 1 The Hi, h obtained by the value and the arithmetic processing.

1 Each data of Ti and Rai is sent to the pressure reduction function calculator 9. It is designed to be output.

The deformation resistance calculator 7 receives H output from the host computer 1,
The average deformation resistance k is determined based on each data of , h, , Ti, VRl, and m, and this determined -1i
1 output the uniformly deformable resistance k to the multiplier 10. The contact arc 1 length calculator 8 receives Hl output from the host computer 1.

The contact arc length thus obtained is outputted to the multiplier 10 and the rolling force function calculator 9, respectively. Pressure horn function calculator 9
is Hl output from the host computer 1.

The rolling blade function Q1'' is determined based on the respective data of h, , Ti, Rai, and Ra, and the determined rolling force function Q0p+
output pi to the multiplier 10;

Multiplier] 0 is the average deformation resistance k output from the deformation resistance calculator 7, the contact arc length 1 output from the contact arc length calculator 8 or 1, and the rolled material output from the host computer 1. 12, the plate width B and the positive value P of the rolling force function calculator are determined, and the calculated load correction value P is output to the cap calculator 5.

The gap calculator 5 calculates the roll gap S to be set based on the CI heavy correction value pln output from the multiplier 10;
The gap setting device 6 sets the roll gap defined by the work roll lla llb to the roll gap S, based on the roll gap S, determined by the gear calculation device 5.

After the roll gap defined by the work rolls lla and llb is set to 81 in this way, hot strip rolling is performed in the i-th strip rolling mill F.

Rolling force function Qm by the rolling force function calculator 9.

In the calculation of l, the roll roughness Ra1 of work rolls lla and llb, material temperature value T1, work rolls 11a and l
By determining the rolling reduction function Qpi in consideration of the rolling number NT of the rolled material 12 after the replacement of the lb, it is possible to obtain the same effect as in the embodiment described above.

As explained above, according to another embodiment of the present invention, when the rolling force function calculator 9 calculates the rolling blade function Q, the work roll 11a.

p] Roll roughness R1 of 11b, material temperature value T1. Since we decided to consider the rolling number NT of the rolled material 12 after replacing the work rolls lla and llb, the work roll l
It has become possible to physically and intuitively variably adjust the roll gap defined by la and llb.

〔Effect of the invention〕

As explained above, according to the first aspect of the present invention, the predicted load value PCAL for the rolled material and the load correction positive coefficient α? The corrected predicted load value pm for the rolled material is obtained by multiplying by According to the second aspect of the present invention, the deformation resistance value K, the contact arc length value hi, and the externally applied workpiece ml are
+ The rolling function Qm obtained on the basis of the above calculation is multiplied by 1 to obtain the corrected predicted load value pH1 for the rolled material, and the 0-ru gap value S corresponding to the obtained corrected predicted load value pif+ is calculated. Since the roll gap value Si was calculated as described above, it is possible to quantitatively express the state of the outer circumferential surface of the work roll pair immediately after the work roll pair is replaced, and also to express the condition of the outer circumferential surface of the work roll pair immediately after the work roll pair is replaced. To model including the transient situation from a state in which no black crust is generated on the outer circumferential surface of the pair of work rolls to a steady state in which black crust is generated approximately evenly on the outer circumferential surface of this pair of work rolls. As a result, it is possible to provide a rolling control device that improves the accuracy of the load prediction rule for a rolled material immediately after work roll replacement, and thereby can obtain a rolled material with excellent plate thickness accuracy.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a rolling control device according to one embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of a rolling control device according to another embodiment of the present invention, and FIG. FIG. 4 is a diagram showing an example of a coffin schedule according to the present invention, and FIG. 4 is a diagram showing a change in plate thickness deviation of a rolled material showing the difference in effectiveness between the present invention and the prior art. 2... Predicted load calculator, 3... Correction formula calculator, 4°10... Multiplier, 5... Gap calculator, 6... Gap setting device, 7... Deformation resistance calculator, 8 ... Contact arc length calculator, 9... Rolling force function calculator, lla, llb.
・Figure 1

Claims (1)

[Scope of Claims] 1. A rolling control device that controls a rolling mill of each stand provided with a plurality of stands to perform hot strip rolling on a given rolled material, comprising: a work roll of each of the rolling mills; roll gap setting means for setting a roll gap defined by a pair of work rolls; input thickness value H_i data, output thickness value h_i data of the rolled material in the rolling mill, and rotational speed value V_R_i data of the work roll pair given from the outside; , a predicted load value calculation means for calculating and outputting a predicted load value P_i^C^A^L for the rolled material based on the material temperature value T_i data of the rolled material and the material information m of the rolled material; Roughness value R_a of the work roll pair
The predicted load value P_i^C based on the _i data, the rolling number N_T data of the rolled material in a state where no oxide film is formed on the outer peripheral surface of the work roll pair after replacing the work roll pair, and the T_i data. ^A^
load correction coefficient calculating means for calculating and outputting a load correction coefficient α_i^P for correcting L; and the predicted load value P_i.
The corrected predicted load value P_i^m for the rolled material is calculated by multiplying ^C^A^L by the load modification coefficient α_i^P.
means for determining and outputting the corrected predicted load value P_i^
A rolling control device comprising: roll gap calculation means for calculating a roll gap value S_i according to m and outputting it to the roll gap setting means. 2. In a rolling control device that controls a rolling mill of each stand provided with a plurality of stands to perform hot strip rolling on a given rolled material, a roll defined by a pair of work rolls of each of the rolling mills. roll gap setting means for setting a gap; input thickness value H_i data, exit thickness value h_i data of the rolled material in the rolling mill, rotation speed value V_R_i data of the work roll pair, and material of the rolled material given from the outside; a deformation resistance value calculation means that calculates and outputs a deformation resistance value k_m_i of the rolled material based on the temperature value T_i data and material information m of the rolled material; and the H_i data, the h_i data, and the work roll given from the outside. Contact arc length value L'_ of the work roll pair and the rolled material based on the roll radius R'_i data of the pair
a contact arc length value calculating means for calculating and outputting i; and a roughness value R_a of the pair of work rolls given from the outside.
_i data, the H_i data, the h_i data,
The R'_i data, the T_i data and the L'_
a rolling force function calculating means for calculating and outputting a rolling force function Q_p_i^m based on i data; Means for calculating and outputting a corrected predicted load value P_i^m for the rolled material by multiplying the plate width B data of the rolled material, and calculating a roll gap value S_i according to the corrected predicted load value P_i^m. A rolling control device comprising: roll gap calculation means for outputting the calculated value to the roll gap setting means.