JPS6243808B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a division control device that divides a material to be divided into a plurality of parts according to a predetermined physical quantity such as length or weight.

Prior to a detailed description of the present invention, the situation in billet rolling equipment where this type of split control device is most often used will be described.

FIG. 1 shows a typical layout of this billet rolling facility. After the material to be rolled 1 is rolled by a group of rolling stands 2, it is divided into several pieces by a shearer 3, and then charged into a heating furnace 4 for the next step. Furthermore, this rolled material 1 is extruded to the next processing step by an extractor 5.

The length of the rolled material 3 cut by the shearing machine 3 after cutting is subject to two physical constraints based on the heating furnace 4 and the extractor 5. That is, 1. The length after cutting has the maximum length Lmax determined by the heating furnace 4.

2 The length after cutting has a minimum length Lmin that can be sufficiently extruded by the extractor 5.

Therefore, if the length after cutting is L, then Lmin≦L≦Lmax ……(1) The following conditional expression holds true.

In order to satisfy this conditional expression, the head end or the tail end of the rolled material 1 is cut by the shearing machine 3, but there are also constraints on this cutting. That is, if the length is too long or if it is too short, it will remain in the path of the material 3 to be rolled, which will cause problems in the operation of the rolling equipment. There is also an upper limit and a lower limit for the cutting length of the head end or tail end.

Therefore, if we set head end cut length = Lh and tail end cut length = Lt, the following equations hold: Lemin≦Lh≦Lemax ……(2) Lemin≦Lt≦Lemax ……(3). Here, Lemin and Lemax
are the maximum and minimum values that constrain the head and tail cut lengths, respectively.

On the other hand, if the total length of the rolled material 1 after rolling is set as Lo, the following equation holds true.

Here, L ₁ , L ₂ , ...Ln are the first time,
2nd, ...indicates the nth cutting length, all of which are (1)
It is determined as a value that satisfies the constraint condition shown in the formula. That is, instead of formula (1), it is possible to set Lmin≦Li≦Lmax (5).

As stated above, all of equations (2), (3), (4), and (5) must be satisfied in order for the cutting control of the billet rolling equipment to be performed satisfactorily.

In other words, this division is used to select the cutting length Li so that all of formulas (2), (3), (4), and (5) are satisfied for the given total length Lo of the rolled material 1. It is a function of the control device.

However, the total length Lo is known after the rolling of the material to be rolled 1 is completed, and before that, it is necessary to use predicted values measured by various methods. This predicted value is naturally accompanied by a length prediction error, so when the predicted value is used to determine the cutting length Li and the head and tail cutting lengths Lh and Lt, the above errors will accumulate at the end, and eventually Given conditional expressions (2), (3),
There is a risk that conditions (4) and (5) may not be satisfied.

Conventionally, there is no reliable division control device of this type, and the operator manually sets the tip cutting length Lh and the tail cutting length Lt, and the division control device simply calculates the above Lh and Lt from the predicted length values. All that was required was to set the value obtained by dividing the value subtracted by equal parts as the cutting length Li.

If the predicted value of the total length Lo after rolling of the rolled material 1 is Lo ₁ , then in the conventional division control device, the cutting length, except for the final one, is Li=Lo ₁ −Lh−Lt/n ……(6 ) However, i=1, 2,...n-1 The final one is It is shown in

Now, if we let ε be the error that the predicted length value Lo ₁ has with respect to the true length Lo, it is shown as Lo ₁ = Lo + ε ...(8), so we can replace equation (8) with equations (6) and (7). ), Li=Lo-Lh-Lt/n+ε/n...(9) where i=1,2,...n-1 Ln=Lo-Lh-Lt/n-n-1 /nε...(10).

By the way, the division length shown in equations (9) and (10)
Both Li and Ln must satisfy equation (5), but equation (10) is clearly more affected by the error ε and is a stricter condition, so only equation (10) will be considered. By substituting equation (10) into equation (5) and sorting it out, we get n・Lminn+Lh+Lt+(n-1)ε≦Lo ≦n・Lmax+Lh+Lt+(n-1)ε ...(11). As for the error ε, only the maximum absolute value E can be defined. That is, −E≦ε≦E (12). Hereinafter, this E will be referred to as the "maximum error".

Therefore, in order for the formula (11) to always hold, n.Lmin+Lh+Lt+(n-1)E≦Lo ≦n.Lmax+Lh+Lt-(n-1)E (13). Unless formula (13) holds true, there is no guarantee that the cutting length initially cut according to formula (6) is truly appropriate.

The basic principle of the conventional division control device is to simply divide the predicted value into equal parts to determine the cutting length, so that (n-1) times as many errors are accumulated in the final cutting length. For this reason, there is often no guarantee that the initially determined cutting length is appropriate. Furthermore, when predicted values with small errors are obtained during the rolling process, it is difficult to utilize these predicted values organically and systematically. Furthermore, even if division cutting is actually possible by adjusting the weight of the rolled material before rolling, there are various drawbacks, such as when it is determined that it is not possible in terms of control.

The present invention was proposed in order to eliminate the drawbacks of the conventional methods described above, and instead of simply dividing the predicted value into equal parts, the present invention examines the possible range at that time for each cut and determines the optimal cutting length. This system is characterized by widening the range in which cutting can be controlled compared to conventional equipment by systematically introducing predicted values with smaller errors obtained during the rolling process. .

An embodiment in which the apparatus of the present invention is applied to dividing a rolled material will be described below with reference to the drawings. As shown in Fig. 2, after rolling, the rolled material 1 having a total length Lo is divided into head end cutting length Lh, 3-division lengths L ₁ , L ₂ and L ₃ , and tail end cutting length Lt. . The head end cutting length Lh is determined by the operator, and the tail end cutting length Lt is set by the control device. This Lh
It will become clear from the following explanation that the method for determining and Lt is merely for convenience and has no relation to the basic principle of the present invention.

FIG. 3 is a block diagram showing an embodiment of the present invention, in which 1 and 3 are the aforementioned rolled material and shearing machine, 11 is a weighing machine for measuring the weight of the rolled material 1 before rolling, and 12 is a This is a length predictor that predicts the length Lo after rolling from the weight side. This length predictor 12
The first cutting length setting device 13 sets the cutting length L ₁ according to the predicted length Lo ₁ of the cutting length. The shearing machine control device 14 first cuts the head end cutting length Lh according to the operator's setting, and then the setting device 13 sends the cut length Lh.
Cut the rolled material 1 according to the value of _L1 .

Prior to the second cutting, the material to be rolled 1 passes through the first stand 15 in the group of rolling stands.
Pulse transmitter 16 attached to stand 15
counts the total number of pulses while the material to be rolled 1 is on the stand 15, and uses this counted value to calculate the length estimator 1.
7 outputs the length predicted value Lo ₂ , which has an even smaller error than that obtained by the predictor 12, to the second cutting length setter 18.

The setting device 18 determines the second cutting length L 2 based on the output signal L ₁ of the setting device 13 and the signal Lo ₂ from the predictor 17, and determines the second cutting length L ₂ by the shear control device 14 in the same way as the first cutting. The rolled material 1 is cut according to the cutting length _L2 .

Prior to the third cutting, the material to be rolled 1 passes through the final stand 19 in the group of rolling stands. A pulse transmitter 20 attached to the stand 19 counts the total number of pulses while the material to be rolled 1 is on this stand, and this count allows the length predictor 21 to have a much greater error than the predictor 17. The smaller length predicted value Lo ₃ is input to the third cutting length setting device 22. This setting device 22 determines the third cutting length L ₃ based on the output signals L ₁ and L ₂ of the setting devices 13 and 18 and the length prediction value Lo ₃ from the predictor 21,
Similarly to the first and second cutting, the shear control device 14 cuts the rolled material 1 according to the cutting length _L3 .
cut. The tail end cutting length Lt is defined as the remaining length after all cutting is completed.

Here, it is assumed that the length Lo of the rolled material 1 after rolling satisfies various physical conditional expressions for being able to be divided and cut. That is, in Fig. 2, Lo=Lh+L ₁ +L ₂ +L ₃ +Lt (14), but equation (5) holds for L ₁ , L ₂ and L ₃ , and Lmin≦L ₁ ≦Lmax ... …(15) Lmin≦L ₂ ≦Lmax …(16) Lmin≦L ₃ ≦Lmax …(17). Also, since the above equation (3) holds true for Lt, equations (3), (15), (16), and (17) can be added to equation (14).
By substituting the formula, we obtain 3・Lmin+Lemin≦Lo−Lh≦3・Lmax+Lemax (18). Since Lmin, Lmax, Lemin and Lemax are known quantities determined by the equipment, and Lh is a known quantity set by the operator, the range of Lo is clear from equation (18). If this conditional expression (18) is compared with the conditional expression (13) associated with a conventional control device, it is clear that the conditional expression (18) is extremely lenient. Conditional expression (18) is realized by adjusting the weight of the material 1 to be rolled before rolling.

In other words, in order to derive equation (13), which is a condition associated with conventional control devices, the value obtained by subtracting the head end cut length Lh and tail end cut length Lt from the predicted length value is divided into equal parts as described above. It is a prerequisite to do so.

That is, the predicted length is already required when setting the cutting length. Equation (13) indicates the condition that the true length Lo must satisfy in order to always satisfy the cutting condition, and in the case of three divisions as in the embodiment of the present invention, that is, n = 3 ... (13A ) to equation (13), 3Lmin+Lh+Lt+2E≦Lo≦3Lmax +Lh+Lt−2E ∴3・Lmin+Lt+2・E≦Lo−Lh ≦3・Lmax+Lt−2・E …(13B)

On the other hand, for the present invention, the above equation (18) is obtained. Compared to this equation (18), in the equation (13B), the allowable range for Lo-Lh is stricter because the upper and lower limits are narrowed by the error term 2·E.

This will be investigated using actual numbers. In equation (30) below, a real value example is presented,
Substituting equation (30) into equation (18) yields 45.1m≦Lo−Lh≦54.6m (18A).

On the other hand, if we use the length predicted from the weight of the rolled material 1 before rolling as the error value E in the above formula (13B), then E = E ₁ , so according to the formula (13B), 49m + Lt ≦Lo−Lh≦50m＋Lt ……(13C).

On the other hand, referring to equations (3) and (30) above,
The above formula (13C) always holds true only when 49.6m≦Lo−Lh≦49.9m (13D) is satisfied.

From the above explanation, it is clear that the conditional expression (18) is extremely relaxed when compared with the conditional expression (13) accompanying the conventional control device. The reason why the conditional expression shown in equation (18) is extremely loose is that in equation (13), the error-related term "E" included due to the functional relationship of the control device is
This is because it is removed in equation (18).

Next, a procedure for sequentially determining the cutting length according to the error of each predicted value, which is a feature of the present invention, will be described. In the present invention, attention is paid to the remaining length of the rolled material 1 after cutting, and each cutting length is determined so that the remaining length always satisfies the existing physical conditional expressions.

The procedure for setting the cutting length determined by the first cutting length setting device 13 shown in FIG. 3 will now be described in detail. The first cutting length L ₁ is expressed by the following formula.

Lo−Lh=L ₁ +L _R1 ……(19) However, Lo is the true total length of rolled material 1 after rolling, Lh
As described above, is defined as the head end cutting length set by the operator, and _L1 is defined as the first cutting length. Furthermore, L _R1 is the remaining length after cutting the first cutting length, and as shown in FIG. 2, L _R1 = L ₂ + L ₃ + Lt (20).

Here, the conditions for the first cutting to be completed will be investigated. For this purpose, it is assumed that the absolute value of the error in the predicted value obtained by the length predictor 12 is the maximum _E1 . In this case, Lmin≦L ₁ ≦Lmax ...(16) Restated, and substituting equations (16), (17), and (3) into equation (20), 2・Lmin＋Lemin≦L _R1 ≦2・Lmax＋Lemax ...(21 ) In the same way as formula (13) was obtained from formula (12), Lo ₁ −Lh−E ₁ ≦Lo−Lh≦Lo ₁ −Lh＋E ₁ ……(22) Furthermore, 3・Lmin＋Lemin≦Lo−Lh ≦3・Lmax＋Lemax ……(18) Obtain the four conditional expressions listed above.

By rearranging equation (19) with respect to L ₁ and substituting equation (21), the following equation is obtained.

Lo−Lh−(2・Lmax+Lemax)≦L ₁ ≦Lo−Lh−(2・Lmin+Lemin) ……(23) Lo ₁ which is the predicted value from equations (15), (18), (22) and (23) Figure 4 is obtained by determining the existence range of Lo-Lh and _L1 for -Lh. In Fig. 4, a hatched area A surrounded by a thick line indicates the range where Lo-Lh exists for a given Lo ₁ -Lh, and a hatched area B surrounded by a thick line indicates the range where Lo-Lh exists for a given Lo 1 -Lh. The thick line part B ₁ connected to it,
B ₂ indicates the range in which L ₁ exists for a given Lo ₁ −Lh. Here, X ₁ , X ₂ , Y ₁ and Y ₂ in the figure are X ₁ = 3・Lmin+Lemin+E ₁ …(24) X ₂ =2・Lmax+Lmin+Lemax−E ₁ …(25) Y ₁ =Lmax+2・Lmin+Lemin+E ₁ … ...(26) Y ₂ = 3・Lmax+Lemax−E ₁ ...(27) Defined as follows. Naturally, unless X ₂ ≧X ₁ or Y ₂ ≧Y ₁ (28), the solution L ₁ does not exist. From equation (28), E ₁ ≦(Lmax−Lmin) +1/2・(Lemax−Lemin) ……(29) is obtained. Equation (29) shows that the solution L ₁ does not exist when the error E ₁ is too large. Equation (29) was obtained from the above-mentioned equation (28), which was found graphically as a condition for the existence of the dotted range B in Figure 4, but here, (22), ( 23) We will explain the procedure for analytically finding both equations. In the simultaneous inequalities (22) and (23), the conditions for the existence of solution _L1 are determined by focusing on Lo−Lh having the range shown in equation (22).

That is, Then, the above equation (22) becomes [Lo−Lh]min≦Lo−Lh≦[Lo−Lh]max
...(22B) is transformed.

Since the solution L ₁ shown in equation (23) exists for Lo−Lh having the range shown in equation (22B), [Lo−Lh]max−(2・Lmax+Lemax) ≦[Lo −Lh〕min−(2・Lmin＋Lemin)
...(23A) must hold. From this equation (23A), 1/2 ([Lo-Lh] max - [Lo-Lh] min) ≦ (Lmax - Lmin) + 1/2 · (Lemax - Lemin) is obtained, and in addition to the above (22A) By substituting the equation, the above-mentioned equation (29) can be obtained as a condition for the existence of solution _L1 .

If the error E ₁ is large and does not satisfy equation (29), equation (23A) will no longer hold, and in equation (23), the value on the right side will not necessarily be larger than the value on the left, so the solution L ₁ ceases to exist. However, in the example of actual values, and is usually satisfied.

As mentioned above, the first cutting length setting device 1
3, L ₁ may be determined from the possible range shown in FIG. Apart from the thick solid line part where L ₁ can only be determined uniquely, in the part indicated by range B, for example, by taking the average of the upper and lower limits,
A method is adopted that statistically develops subsequent cutting control advantageously.

The procedure for determining the first cutting length setting value _L1 in the setter 13 has been described above with reference to FIG.

Next, the procedure for setting the second cutting length _L2 determined by the setting device 13 will be described. This procedure is completely the same as that in the setting device 13. That is, Lo−Lh−L ₁ =L ₂ +L _R2 ……(31) L _R2 =L ₃ +Lt ……(32) Lmin≦L ₂ ≦Lmax …(16) Reposted Lmin+Lemin≦L _R2 ≦Lmax+Lemax ……( 33) Lo ₂ −Lh−L ₁ −E ₂ ≦Lo−Lh−L ₁ ≦Lo ₂ −Lh−L ₁ +E ₂ ……(34) 2・Lmin＋Lemin≦Lo−Lh−L ₁ =L _R1 ≦2・Lmax+Lemax ...(21) Reposted Lo−Lh−L ₁ −(Lmax+Lemax)≦L ₂ ≦Lo−Lh−L ₁ −(Lmin+Lemin) ),
(15), (21), (22), (18), and (23), respectively. Here, L _R2 is the remaining length after cutting the second cutting length, Lo ₂ is the predicted value of the total length obtained by the length predictor 17, and E ₂ is the absolute maximum error value of the predicted value Lo ₂ . be. (16),
The predicted value is calculated by equations (21), (34) and (35).
When the existence range of Lo-Lh-L ₁ and L ₂ is determined for Lo ₂ -Lh-L ₁ , FIG. 5 is obtained. However, in Figure 5, It is. Therefore, corresponding to equation (29), regarding the error E ₂ , under the condition that E ₂ ≦ 1/2 (Lmax − Lmin) + (Lemax − Lemin) ... (37), the predicted value Lo ₂ For −Lh−L ₁ , the true value Lo shown by range C within the thick line in the figure
According to -Lh- _L1 , a possible range of _L2 is obtained as the thick line range D in the figure and the thick line parts _C1 and _C2 connected thereto. The determination of L ₂ within this range is the same procedure as the determination of L ₁ above. An example of the value of the error E ₂ is E ₂ =1.0m (38), so by referring to equation (30), it can be seen that equation (37) is usually satisfied.

Finally, the procedure for setting the cutting length _L3 determined by the setting device 22 shown in FIG. 3 will be described.
This procedure is also completely the same as that in the setting device 13. That is, Lo−Lh−L ₁ −L ₂ =L ₃ +Lt ……(39) Lmin≦L ₃ ≦Lmax ……(17) Reprinted Lemin≦Lt≦Lemax ……(3) Reprinted Lo ₃ −Lh−L ₁ −L ₂ −E ₃ ≦Lo−Lh−L ₁ −L ₂ ≦Lo ₃ −Lh−L ₁ −L ₂ ＋E ₃ ……(40) Lmin＋Lemin≦Lo−Lh−L ₁ −L ₂ ＝L _R2 ≦Lmax＋Lemax ...(33) Reposted Lo−Lh−L ₁ −L ₂ −Lemax≦L ₃ ≦Lo−Lh−L ₁ −L ₂ =Lemin ...Equations (41) are expressed as (19), ( 15),
(21), (22), (18), and (23), respectively. Here Lo ₃ is length predictor 21
The predicted value of the total length obtained by _E3 is the absolute maximum error value of the predicted value _Lo2 . (17), (33),
(39) and (40), the predicted value Lo ₃
−Lh−L ₁ −L ₂ , Lo−Lh−L ₁ −L ₂ and
Figure 6 is obtained by finding the range of existence of L ₃ .

However, in Figure 6 It is. Therefore, regarding the error E ₃ for equation (29), the predicted value under the condition that E ₂ ≦ 1/2 (Lemax − Lemin) ...(43) is the predicted value Lo ₃ −Lh−L ₁ −L ₂
, the true value Lo shown by the thick line range E in the figure
According to -Lh-L ₁ -L ₂ , a possible range of L ₃ is obtained as the range F within the thick line in the figure and the thick line portion F ₁ ;F ₂ connected thereto. Unlike L ₁ and L ₂ , there are no constraints on determining L ₃ within this range, so it can be arbitrarily selected. Therefore, if possible, L ₃ =
A decision such as selecting L ₂ is taken. An example of the error E ₃ is E ₃ =0.2m (44). Therefore, referring to equation (30), it can be seen that equation (43) is usually satisfied.

The features of the present invention described above with respect to the embodiment shown in FIG. 3 are that the physical conditions are satisfied before the start of cutting. Assuming that, for each cut inductively, 2・Lmin+Lemin≦L _R1 ≦2・Lmax+Lemax ...(21) Restated Lmin+Lemin≦L _R1 ≦Lmax+Lemin
...(33) Reposted Lemin≦Lt≦Lemax ...(3) As shown again, the purpose is to determine the cutting value so that a condition completely symmetrical to equation (18) holds after each cut. In other words, by cutting so that the remaining length after each cut can be cut without fail, it is possible to smoothly introduce a new total length predicted value with few errors, and to use the information of this new predicted value without wasting it. It is characterized by

In the above embodiments, the overall length Lo is estimated from the weight of the material to be rolled before rolling, but it is clear that the present invention can be carried out by any method.

In the above embodiment, the cranial and caudal cuts are
Although the accompanying example has been described, it is equally applicable even if one or both of these are not accompanied.

Furthermore, in the above embodiment, one predicted value was accompanied by one cut, but even if one predicted value is accompanied by multiple cuts, the length between the plurality of cuts is If the mutual relationship is known, the present invention is similarly applicable.

The present invention is applicable not only to the shear control of the above-mentioned rolling equipment, but also to all equipment having the same mathematical structure.

Sequentially divide the entire amount Wo such as length and weight into n pieces
When dividing into W ₁ W ₂ . . . W _o , each component Wi (i=1, 2, . . . , n) to be divided has its own upper and lower limit values. i.e. Wimin≦Wi≦Wimax ……(46) When the division is expressed by two equations,
It is clear that the present invention is applied when m remaining amount predicted values Wo ₁ , Wo _{2 .} . . , Wom are sequentially given to the overall amount Wo. In this case, the remaining amount after each division maintains the lower and upper limits allowed for the remaining amount, regardless of the prediction error of the predicted remaining amount, i.e. The respective division amounts are set as follows. However, in the above, m and n are integers of 1 or more, Wo,
Wo ₁ , Wo ₂ , …Wom and W ₁ , W ₂ …Wn,
Wimax is a positive number, and Wimin is 0 or a positive number.

Also, for example, if there is an error between the actual value of the shear length and the set value of the shearing machine control device 14 shown in FIG.
It is also easy to incorporate this error into the prediction error to determine the set value.

As described above, when dividing the total amount sequentially, the division control device of the present invention takes into account the remaining amount determined by the aforementioned division so that it can be re-divided, so that the predictions that are sequentially introduced to the total amount are Values can be used without wastage, and there is an effect that the restrictive conditions that exist on the total amount can be relaxed compared to conventional divided control devices.

[Brief explanation of the drawing]

Fig. 1 is a layout diagram of a billet rolling facility to which the split control device of the present invention is most typically applied; FIGS. 4 to 6 are block diagrams showing one embodiment of the invention division control device, and are explanatory diagrams showing the first to third cutting situations by the invention division control device. 1... Material to be rolled, 2... Rolling stand group, 3...
...Shearing machine, 4...Heating furnace, 5...Extraction machine, 11...
... Weighing machine, 12 ... Length predictor, 13, 18, 2
2... Cutting length setting device, 15, 19... Rolling stand, 16, 20... Pulse oscillator, 17, 21
...Length predictor, 14...Shearing machine control device. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] 1. In a division control device that divides a material to be divided into a plurality of parts according to a predetermined physical quantity, a prediction device that sequentially predicts the physical quantity of the material to be divided after division in each division process, and a predicted value of this prediction device. A dividing control device comprising: a dividing amount setting device for setting a dividing amount according to a dividing amount; and a dividing device for dividing the material according to a setting value of the dividing amount setting device.