SU1502147A1 - Automatic system for controlling per cent reduction of the billet being rolled - Google Patents

Abstract

This invention relates to the automation of temper mills and is intended to automatically control the relative reduction of the rolled strip. The goal is to improve the quality of the strip by increasing speed and control accuracy. The goal is achieved by introducing a parametrically calculated initial coefficient into the self-adjusting system and parametric compensation of input disturbances. The initial transfer coefficient is calculated from the cage pressure, reduction and strip thickness signals and is entered at the beginning of the rolling of each strip. Subsequently, the coefficient is corrected according to the ratio of deviation of reduction from the task before and after the regulating pulse. The effect of disturbances on the adaptation process is taken into account by introducing a compensating signal calculated from the values of the pressure in the cage, the reduction and the magnitude of the displacement of the pressure screws. 2 Il.

Description

The invention relates to the automation of rolling production, namely, to the automation of the training mills of rolling mills.

The purpose of the invention is to improve the quality of the band by increasing the speed and accuracy of the adjustment.

FIG. 1 is a block diagram of an automatic control system for relative crimping of a rolled strip; in fig. 2 - a regulating impulse formation unit,

The system consists of impulse sensors 1 and 2 of the strip speed, a reduction meter 3, a comparison unit 4.

node 5 averaging unit 6 forming a control pulse, system 7 control push screws, storage node 8, nodes 9 and 10 comparison, divider 11, functional converter 12, multiplier 13, storage node 14, switch 15, storage node 16, unit 17 control , node 18 for determining the start of a roll, element 19 OR, pressure meter 20, divider 21, adder 22, functional converter 23, memory node 24, comparison nodes 25 and 26, divider 27.

SP

about to

3,150

A reduction meter 3 connected by inputs to the outputs of the pulse sensors I and 2 strip speeds, through the comparison node 4, the second input of which is the reduction reference input, is connected to the first input of the averaging node 5, the second input of which is connected to the output of the speed I pulse sensor. the first output of the averaging unit 5 is connected to the first input of the regulating impulse formation unit 6 and to one of the inputs of the control unit 17, the other input of which is connected to the first output of the regulating impulse generating unit 6, the first output - the third output m input node 6, the storage node 8 is connected to the first output of the first node of the averaging node 5, and the second to the first output of the regulating pulse forming unit 6, the comparison node 9 is connected to the first output of the averaging node 5 and the output of the storage node 8, and output Comparison node 10 with one of the inputs of the divider 11, the other input of which is connected to the output of the knowledgeable node 8, the output of the divider 1 through the functional converter 12 is connected to one of the inputs of the multiplier 13, the other input of which is connected to the output of the 3-node node 16 and the fourth input of the regulating impulse formation unit 6, the memorizing unit 14 is connected with the outputs of the multiplier 13 and the second output of the control unit 17, and the output through the switch 15 with one of the inputs of the storage unit 16, the input node 18 connected to the output of the pulse strip speed sensor 1, and the output to one of the inputs of the switch 15 and to the input of the element OR 19, the other input of which is connected to the third output of the control unit 17, and the output to the input of the adder 22, the second input of which is . the input for signal feeding is the thickness of the strip, and the output through the functional converter 23 is connected to the corresponding input of the switch 15, the storage node 24 is connected by the first and second inputs to the output of the pressure gauge 20 and the first output of the regulation shaping node 6, respectively. the first input of the comparison unit 25, the second input of which is connected to

0 5 0 5 0 5 0 5

the pressure gauge 20 moves and the output goes through the comparison node 26 with the third output of the control pulse generation unit 6, the output is connected to one of the inputs of the divider 27, the second input of which is connected to the output of the divider 21, and the output is connected to the second input of the comparison node 10.

The control pulse generation unit 6 (Fig. 2) consists of a comparison unit 28, a key 29, a relay amplifier 30 with a dead zone, keys 31 and 32, a reset generator 33 (for example, a one-shot), a block for calculating the movement of pressure screws (for example, an integrator ) and multiplier 35.

The control unit 17 can be performed, for example, on the basis of a series-connected RS flip-flop and two one-vibrators, the R- and S- inputs of the trigger being the device inputs, and the outputs of the trigger and the one-vibrators being the first, second and third outputs of the device.

As a node 18 for determining the start of a roll, a sequentially included frequency meter and comparator can be used, for example, built on the basis of KP1I08 PP1 and K554SAZ chips, with the input of the frequency meter being the input of node 18, and the output of the comparator - output. One of the inputs of the comparator is connected to the output of the frequency meter, the other is supplied with a reference voltage.

The system works as follows.

The signals from the pulse sensors 1 and 2 of the speed of the band (Fig. I) are fed to the input of the meter 3 relative reduction, the output of which produces a signal proportional to the relative compression of the band. This signal at comparison node 4 is compared with the relative reduction setting signal. The compression mismatch signal is fed from the output of the comparison node 4 to the first input of the averaging node 5. At the first output of node 5, a signal of 6 G is formed, which is the same as the average mismatch value of the compression for the constant path of the band, calculated from the number of pulses received from the pulse sensor 1 of the band speed, to the second input of the node 5 of averaging.

coefficient calculation

Memory

proportional to the ratio em to determine the value

JP T

letting

51

When reaching a path equal to the averaging put, a signal is generated at the second output of the averaging node 5 allowing the formation of a control pulse. The averaged error signal goes to the first input of the regulating impulse formation unit 6, where when this signal exceeds the set insensitivity zone and if there is an enable signal from the second output of the averaging node 5, as well as in the absence of the inhibitory signal coming from the first signal - the stroke of the control unit 16, a control pulse is generated.

The regulating impulse acts on the control screw drive system 7, which at the same time moves in the direction of decreasing the error. The signal at the first output of the averaging unit 5 during the action of the regulating pulse remains constant.

After the end of the movement of the pressure devices by a signal coming from the second output of the node 6 to the third input of the node 5 of averaging, the installation of the node 5 to the initial state is performed.

The duration of the regulating impulse is determined by the average discrepancy of compression and the established coefficient of the model, which starts at the fourth input of the regulating impulse formation unit 6 from the output of the storage unit 16.

The meter 20, the divider 21, the adder 22, the converter 23 is intended for parametric output

F

3dC between the pressure in the cage and compression during training is ste. foamy character with an indicator practically independent of the properties of the rolled strip. The outcome of this 3 P go-private derivative

one

n,

(one)

Where

K is the coefficient depending on the parameters of the mill stand.

7

dd

To calculate the coefficient

The measured reduction signal is used, which allows determining the coefficient before turning on the controller, since the approximate equality of the specified and measured reduction is achieved only when the controller is operating.

A functional transducer 23 having a hyperbolic characteristic transforms the coefficient

3d “- in the inverse coefficient,

Charger d

At the beginning of the coil rolling, when the mill is accelerated, the frequency at the output of the sensor 1 increases, and the output signal of the frequency meter at node 18 reaches the level of the comparator operation equal to the reference voltage. By a signal from the output of the roll start determination unit 18, the switch 15 connects the output of the functional converter 23 to the output of the storage unit 16 and, through the OR element 19, acts on the storage unit 16, translating it to the recording state. The parametrically calculated coefficient recorded in the storage node 16 is the initial coefficient of the model.

According to the results of testing the resulting mismatch, the regulator makes an adjustment of the model coefficient. After the initial portion of the rolled roll is finished, the switch 15 switches by a signal from the output of the node 18, and the corrected model coefficient arrives at the input of the storage node 16.

The adjustment of the model coefficient is performed on the g-elements as follows.

When working off in the i-th cycle of misalignment &Jj; the pressure screws move a distance ud equal to

y

Ad

(2)

At the same time, the change is actually about the reduction on the strip, which is determined by the sum of the changes of reduction caused by the regulating and disturbing effects,

The change in reduction caused by the regulatory action is determined by the true K03 (tjf |) HnMCHTOM stap K.

(3)

 U per

U dK

st

Changes in the strip stiffness are caused by changes in the chemical composition or impaired annealing technology and are relatively slow, and therefore practically do not cause a reduction in the reduction during the time of the mismatch and the subsequent measurement and averaging. In this case, the main disturbing effect can be considered as the change in the input thickness, which allows the resultant change in crimping (D to determine the outcome from the change in pressure in the adhesive tape P. R

The change in pressure in the cage, arising as a result of the adjustment, can be calculated as the product of the elastic modulus of the cage Kj by the amount of displacement of the pressure screws A d.

The change in pressure caused by the change in input thickness, taking into account the fact that the stiffness of the strip is K;

/ iP,

eosm

& P - K; & d.

(BUT)

ER

given that the derivative

P is proportional to y change

ABOUT

compression caused by this disturbance is equal to

& p - to; d

r / g

(five)

The total change in reduction is determined from the formulas- (3,4,5)

AG.-H-- MK, ... (6) 0

From the ratio of the formulas: (3) and (6) we obtain

from 5

0

five

0

five

0

After the end of the regulating pulse and the subsequent cycle of measurement and averaging, a signal jju, is generated at the first output of the node 5 of averaging.

The signal & &g;, is compared at node 9 of the comparison. From the resulting difference & - Lou; + | in comparison node 10, the change in crimping caused by the change in input thickness, calculated in accordance with formula (5) on elements 24-27, is subtracted.

The change in pressure U, P is calculated at comparison node 25, as the pressure difference in the i and i + 1 measurements. At the comparison node 26, a signal is subtracted from the signal P proportional to the movement of the pressure screws 9d formed at the third output of the node 6 (the output of the pressure screws calculating movement block 34 in FIG. 2).

In the divider 27, the output signal of the comparator node 26 is divided by the value of P / y.

Lou signals; and &y; - & y ts ,,, enter the inputs of the divider 11, the output of which forms the ratio of the coefficients of the mill and the model

KO.

The signal in the functional converter 12 is converted to

TO

  - where - m1

coefficient coefficient between K, and K "; , which allows in the process of adaptation to approach K asymptotically. The coefficient of the model, recorded in the i-M cycle in the storage node 16, is multiplied in multiplier 13

1 L Ifi

on signal

TO

and corrected

h; -H; -

LR -

rtu

4fl

. (7)

During the formation of the regulating pulse by the node 6, the storage nodes 8 and 24 are transferred to the recording mode and the values of the LL average discrepancy are recorded in them; and pressures that exist prior to the start of testing the mismatch. The control unit 17 is switched to ready mode at this time.

The coefficient Kd. is recorded in the storage node 14, and then rewritten into the storage node 16.

The storage units 14 and 16 are controlled by the control unit 17.

At the end of the a + 1 averaging cycle, a signal is generated at the second output of node 5 of the averaging, which acts on control block 17, and signals that periodically store memory nodes 14 (directly) and 16 appear sequentially at the second and third outputs of the output (through OR 19 ) in the recording state. At the time of the formation of these signals at the first output of the control unit 17, a signal is generated that prohibits the formation of a control pulse for the recording time,

Thus, the coefficient of the model is initially determined parametrically and then adjusted for changes in input thickness.

Claims (1)

The present invention allows to precisely work out the resulting mismatch per one control pulse, practically throughout the entire rolled strip and, therefore, compared with the known systems for controlling the relative bandwidth, it has higher speed and accuracy, which ultimately leads to an increase in the quality of the strip. Invention Formula A system for automatically controlling the relative crimping of the rolled strip, comprising impulse velocity sensors of the strip, a reduction gauge connected to them, the output of which through the first comparison node is connected to the first input of the averaging node, the second input of which is connected to the output of the first pulse sensor, the first output of the averaging node connected to the first inputs of the first storage node, the second comparison node and the regulating pulse forming node connected to the tap control system by the first output with screws, with the second input of the first storage node and with the first input of the control unit, the second output with the third input of the averaging node, the second output of which is connected to the second input of the control pulse shaping unit and the second input of the control unit whose first output is connected to the third input of the regulating pulse formation unit, the first input of the first divider is connected to the second input of the second comparison node and to the output of the first storage node, and the output is connected to the first through a functional converter the input of the multiplier, the second input of which is connected to the output of the third power node and the fourth input of the node of the regulating unit five 0 five 0 five 0 five 0 five pulse, and the output of the multiplier is connected to the first input of the second malignant well, the second input of which is connected to the second output of the control unit, the second input of the first comparison node is designed to reduce the quality of the band due to the increase in speed and accuracy of regulation, it additionally contains a switch, a roll start determination unit, a 1-SHI element, a pressure meter, QTa pofi and third dividers, an adder, a second function-converter, a hard memory node, the third one, the fourth and fifth comparison nodes, the first input of the third comparison node is connected to the output of the second comparison node, the second input - to the output of the second divider, the output - to the second input of the first divider, the first input of the second divider is connected to the code of the fourth comparison node, the first input of which connected to the third output of the regulating pulse formation unit, the second to the output of the fifth comparison node, the first input of which is connected to the output of the fourth storage node; the first input of the second is connected to the first exit of the formation node regulating pulse, the second input is connected to the second input of the first comparison node, to the output of the pressure meter and to the first input of the third divider, the second input of which is connected to the output of the compression meter, and the output to the second input of the second divider, the second input of which is an input for supplying a signal The thickness of the strip, and the output of the adder through the second functional converter is connected to the first input of the switch, the second input of which is connected to the output of the second memory node, the output is The first input of the third storage node, the third input of the switch is connected to the output of the roll start detection node, the input of which is connected to the output of the first pulse strip speed sensor, the first input of the ILM element is connected to the output of the roll start detection node, the second input is connected to the third output of the control unit, and the output - with the second of the third storage node.