JPH01154812A - Meandering control device for continuous rolling mill - Google Patents

Abstract

PURPOSE:To accurately and effectively control the meandering value just under the part of a roll by computing to estimate the condition of the meandering phenomena through a difference value between the positions of the rolling reduction and a difference value between rolling loads at both ends of the rolling roll and by using the obtained wedge value for computing the latter stage of the meandering value. CONSTITUTION:A difference of rolling reaction forces between both ends of one pair of the rolling rolls 2, 2 justerposed facing each other and difference between roll clearances are detected, and the internal state of the meandering phenomena is estimated using these detected values and modeling equation at an arithmetic section 19 for estimating quantity of state. Based on this estimated result, a controlled variable is calculated on a meandering value control and arithmetic section 16 to control said roll clearance. Together with this, the wedge values of both ends of a stock 1 to be rolled obtained by said arithmetic section 19 of the quantity of state, are transferred to a meandering value arithmetic unit 21 of the latter stage stand through a data transferring device 20. At this time, said wedge values are substituted into the meandering phenomena model to obtain the meandering value. Based on this meandering value, at the time when said arithmetic point on the upstream stand arrives at this stand the difference between the roll clearances is controlled through the meandering value control and arithmetic section 16 to control the meandering value.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention provides a continuous method for suppressing and controlling the meandering of the rolled material when the rolled material is sequentially passed between rolling rolls of a plurality of rolling mills. This invention relates to a meandering control device for a rolling mill.

[Conventional technology]

FIG. 4 is a block diagram showing a conventional meandering control device disclosed in, for example, Japanese Unexamined Patent Publication No. 55-88914. In the figure, %1 indicates a material to be rolled, and 2 indicates rolling rolls that sandwich the material to be rolled 1 from above and below. , 3 is a reinforcement roll, 4 is a roll chock, 5,
6 is a rolling load detector, 7.8 is a rolling position detector, 9,1
0 is a hydraulic cylinder, 11.12 is a reduction position controller, 13
14 is an arithmetic unit that receives the detected values Pv and Pd from the rolling load detectors 5 and 6 as inputs; 14 is an arithmetic unit that receives the detected values Sw and Sd from the rolling position detectors 7 and 8; 15 is an arithmetic unit 13 16 is a meandering control arithmetic unit that inputs the estimated meandering amount ya from the arithmetic unit 15.

Next, the operation of the meandering control device will be explained. Detection values Pw and Pd from the rolling load detectors 5 and 6 at both ends of the rolled material 1 rolled between the rolling rolls 2.2 and detection values Sw and Sd from the rolling position detectors 7 and 8. Using the calculators 13 and 14, the load difference signal δP and the lowering position difference signal δS
After calculating the meandering estimated amount yc, the arithmetic unit 15 which receives both signals as input is outputted.

The meandering # control unit 16 inputs the meandering estimated amount yc, and
The rolling position difference adjustment amount δS''' is determined and outputted, and this rolling position difference adjustment amount δS'' is supplied to two sets of rolling position control systems consisting of a hydraulic cylinder 9°10 and a rolling position controller 11.12. The meandering of the rolled material 1 is controlled by adjusting the rolling position difference (also referred to as leveling amount) at both ends of the roll.

Further, FIG. 5 is a block diagram showing another example of the conventional meandering control device disclosed in the above-mentioned publication, and the same parts as in FIG. 4 are given the same reference numerals. In FIG. 5, 17 is a position detector for the rolled material 1, and 18 is a meandering amount detector.

Next, the operation of the meandering control device shown in FIG. 5 will be explained.

The position and meandering amount of the rolled material 1 rolled between the rolling rolls 2 and 2 are detected by a position detector 17 and a meandering amount detector 18, respectively, and the output of the rain detector is detected as the meandering amount y.
c is inputted to the meandering control calculating section 16, and the rolling down position difference is adjusted using the rolling down position difference adjustment amount δS'' outputted from the meandering control calculating section 16 in the same manner as in the example in FIG.

In any of the meandering control devices described above, in order to improve the control effect, the reduction position difference adjustment amount δS1 is determined by a proportional amount and a time differential amount of the meandering amount yc or the estimated meandering amount yc. That is, a (proportional and sufficient differential) control calculation is performed.

[Problem that the invention seeks to solve]

Since the meandering control device of a conventional continuous rolling mill has one or more configurations, the meandering control device shown in FIG. If not, an error will occur in the calculation of the estimated meandering amount yc by adding the detected load difference value and the detected value of the lowered position difference.

Further, according to the meandering control device shown in FIG. 5, since the meandering amount detector is installed at a point separated from the rolling roll by a certain distance or more, it is impossible to detect the meandering amount directly below the rolling roll.

In other words, when the meandering amount detector 18 is installed on the downstream side of the rolling rolls, as shown in FIG. Even if meandering occurs, meandering cannot be detected until the tip of the rolled material reaches the state shown in (■) or later, and there is a time delay before meandering is detected.

In addition, when the meandering amount detector 18 is installed on the upstream side of the rolling roll, as shown in FIG. However, there are still some parts that cannot be detected.

Furthermore, considering that in normal rolling operations, meandering occurs most frequently at the tip and tail ends of the rolled material 1, it is anticipated that there will be cases where sufficient meandering control cannot be implemented. was there.

Figure 8 is a model showing the temporal change in meandering described in "Theory and Practice of Sheet Rolling" published by the Japan Iron and Steel Institute, September 1, 1980, page 244. In Figure 8,
K is the deflection spring constant of the housing, chock, etc., KF
is the flat spring constant between the rolls, k is the flat spring constant of the work roll in the roll bite, 1□ is the distance between the left and right load points,
b is the width of the material to be rolled, h is the outlet side plate thickness, H is the inlet side plate thickness, P is the rolling reaction force, IQ is the roll body length, yc is the meandering amount, ■ is the rolling speed, and S is Laplace.

According to the above model, the factors that determine the meandering phenomenon of the rolled material are the rolling position difference signal δS and the difference between the left and right ends of the entrance plate thickness change (the amount of wedge per entry side plate) δH, and as a result, the It is explained that meandering yc occurs in the rolled material, inducing a rolling load difference δP between both ends of the roll.

Considering the principle of this meandering occurrence, it is clear that the meandering amount 'JQ cannot be accurately estimated only from the detected rolling position difference δS and the rolling load difference δP.

That is, if there is a change in the amount of wedging in the entrance side plate thickness, the calculated value of the estimated meandering amount will include a considerable error. Moreover, one of the main causes of meandering in rolled material is
It is a well-known fact that the difference in thickness between both ends of the entry side has an effect, and there has been a problem in that conventional meandering control devices cannot exhibit sufficient effects.

This invention was made to solve the above-mentioned problems, and even if there is a change in the amount of wedging in the entrance side thickness, the invention always detects the accurate amount of meandering directly under the rolling rolls, and the detection results can be used. An object of the present invention is to obtain a meandering control device that can effectively suppress and control meandering phenomena in all rolling stands of a continuous rolling mill.

[Means for solving problems]

The meandering control device according to the present invention uses a linear model equation that describes the meandering phenomenon in addition to the difference δS and the rolling load difference δP to determine the meandering level at both ends of the rolling roll that can be detected in a normal rolling mill. A state quantity estimation calculation unit that performs state estimation calculations, and a plate thickness difference between both ends of the strip on the exit side of the rolling mill of the material to be rolled obtained as a calculation result from this state estimation calculation unit are sent to the meandering amount calculation unit of the next rolling stand. and a data transfer device provided between the rolling stands to supply the data.

[Effect]

The state quantity estimation calculation unit in this invention estimates and calculates the internal state quantity related to the meandering phenomenon using a model formula expressing the meandering phenomenon in addition to the rolling position difference and the rolling load difference at both ends of the rolling roll. As a result, the entrance side plate thickness wedge amount can be calculated accurately, and by transferring the calculation result to the next rolling stand, it is possible to accurately calculate the meandering amount in the next rolling stand.

【Example〕

An embodiment of the present invention will be described below with reference to the drawings. The same parts with the same reference numerals as in FIG. 4 above indicate the configuration of the most upstream stand of the continuous rolling mill, and in FIG.
19 is a load difference signal δ supplied from the calculators 13 and 14;
This is a calculation unit that performs arithmetic processing based on the meandering position difference signal δS and the meandering estimated amount ya and the meandering degree state quantity.

The state quantity estimation calculation unit 19 uses the well-known theory of state observers based on the block diagram of FIG. 2, which is an equivalent transformation of the model block of FIG. 8 that explains the meandering phenomenon.
It is possible to reduce any initial estimated error amount to zero within an arbitrary time.

The reason why the state quantity estimation calculation unit 19 can perform the above calculation is that the model equation governing the meandering phenomenon can be described as follows. That is, the above equations (2) and (3) are generally expressed as follows.

−x = A x + b u −=
(2)'ty=cx+du...(3)'In addition, in FIG. 2, the relationship between the parameters is Qh=TachiLah...(6)6P.

The meandering control calculation unit 16 inputs the estimated meandering amount 3'O from the state quantity estimation calculation unit 19 and the meandering change differential amount ÷ C2 input side plate thickness wedge amount δH, determines and outputs the reduction position difference adjustment amount δS'', and outputs this. The rolling position difference adjustment amount δS'' is supplied to two sets of rolling position control systems to adjust the rolling position difference at both ends of the rolling rolls, thereby controlling the meandering of the rolled material 1.

In addition, the state quantity estimation calculation unit 19 calculates and outputs the exit side plate thickness wedge amount δh of the stand (hereinafter referred to as the i-th stand) from the model equation, and outputs this output side plate thickness wedge amount δh of the next stand. (hereinafter referred to as the i+1st stand).

Assuming that the entrance side plate thickness wedge amount of the i+1 stand is known, it is possible to accurately estimate the amount of meandering without requiring complicated calculations, and its configuration is shown in FIG. 3.

In FIG. 3, 20 is a data transfer device between stands, and this data transfer device 20 is an output plate thickness wedge amount δh output from the state quantity estimation calculation unit 19 of the i-th stand.
, is sequentially memorized, the length of the rolled material sent out on the exit side of the i-th stand is measured, and when the point reaches directly under the i+1-th stand, this is set as the estimated meandering amount W of the i-th stand.
Output to 21.

The arrival at the next stand is determined as follows.

That is, using a pulse oscillator (not shown) attached to the rolling roll of the i-th stand, and taking into account the advance rate of the material to be rolled, the feed length is measured using the following formula, Q = πD X- X (Hf) ・=
(15) R However.

D: Roll diameter N: Pulse count number Np: Number of pulses per revolution of the pulse oscillator: Advance rate When this length Ω becomes equal to the distance between the stands, the next stand is reached.

In the (i+1)th stand, the state estimation calculation unit 19 required in the jth stand is not used, and the lowering position difference signal δSl+I at the (i+1)th stand is used.
*Using the load difference signal δPI+1 at both ends of the rolling roll and the transferred inlet thickness wedge amount δH1,, the estimated meandering amount 3'CI+1+its time differential value ycl+t is determined.

The following is calculated by the meandering amount calculation device 21 in the same way as for the i-th stand) 'Cl+1+ polyel+1+ δH1÷1
The reduction position difference adjustment amount δSl+1''' is determined by guiding the (i+1)th stand to the meandering control calculation unit 16. (Here, the subscript i+1 indicates that the capacity corresponds to the (i+1) stand. ) Below, the above configuration is
, i+1 . . . i + n stands of a continuous rolling mill.

In the above embodiment, a hydraulic lowering device using hydraulic pressure is assumed as the lowering position control device 11 and 12 which input the control output signal for meandering control, but the lowering position control device 11
．． 12 may be an electric rolling down device using an electric motor, or a roll pending force control device that controls the roll pending force at both ends of the rolling roll in addition to the rolling down position control device may have the same effect as the above embodiment. play.

〔Effect of the invention〕

As described above, according to the present invention, in addition to the rolling position difference and the rolling load difference at both ends of the roll, a model equation describing the meandering phenomenon is used to perform calculations for estimating the meandering phenomenon state,
The structure is such that the plate thickness difference (wedge amount) between both ends of the rolled material determined at the upstream stand is sequentially transferred to the downstream stand and used for calculating the meandering amount at the downstream stand.
Without installing a meandering detector, and even when there is a change in the wedging amount in the entrance plate thickness, the amount of meandering directly below the roll can be accurately determined, effectively suppressing the meandering phenomenon in all stands of a continuous rolling mill. It has the effect of being controllable.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the most upstream stand showing a meandering control device for a continuous rolling mill according to an embodiment of the present invention, FIG. 2 is a block diagram illustrating the meandering phenomenon used in this invention, and FIG. 3 is a block diagram of the present invention. Figures 4 and 5 are block diagrams of a stand to which a conventional meandering control device is applied, and Figures 6 and 7 are a block diagram showing a meandering control device for a continuous rolling mill. FIG. 8 is an explanatory diagram illustrating that the amount of meandering directly below cannot be detected, and FIG. 8 is a model diagram showing temporal changes in meandering including the rolling mill. 1 is a rolled material, 2 is a rolling roll, 19 is a state quantity estimation calculation unit, 20 is a data transfer device, and 21 is a meandering amount calculation device. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Patent applicant: Mitsubishi Electric Corporation and Nino 1: Flea 50-1. LO> 3rd YatM Tando
Figure 5

Claims (1)

[Claims] A function that detects the difference in rolling reaction force between both ends of a pair of rolling rolls arranged in parallel and oppositely, and the difference in the gap between the upper and lower rolls at both ends, and controls the meandering of the rolled material by adjusting the amount of the difference in the gap between the upper and lower rolls at both ends. In a meandering control device for a continuous rolling mill having a large number of stands, the internal state quantity related to the meandering phenomenon is estimated using the rolling reaction force difference, the upper and lower roll gap difference, and a model equation expressing the meandering phenomenon. When the state quantity estimation calculation unit provided in the most upstream stand so as to adjust the difference in the gap between the upper and lower rolls at both ends of the rolling rolls of the stand based on the estimation result, and the calculation point of the state quantity estimation calculation unit reach directly below the downstream stand. The amount of plate thickness difference between both ends of the rolled material at the exit side of the most upstream stand obtained from the state quantity estimation calculation unit is applied to the downstream stand as the known plate thickness difference between both ends of the rolled material at the entry side of the downstream stand. a data transfer device provided between the stands so as to transfer the data; and a most upstream stand for substituting the thickness difference between both ends of the rolled material from the upstream stand supplied through the data transfer device into the meandering phenomenon model. A meandering control device for a continuous rolling mill, comprising: a meandering amount calculation device provided in each downstream stand except for the meandering amount calculation device.