SU692648A1 - Arrangement for automatic accurate arresting or reversible rolling mill with coilers - Google Patents

Description

The invention relates to the field of electric drive control of reversible rolling mills and is intended for use in automatic stop rolling mills with coilers for rolling ferrous and non-ferrous metals, in particular cold rolling reversing mills.

A device for automatic exact stopping of cold rolling mills is known, which contains pulse angle sensors: rotation of winders, strip length measuring unit on the winder, decoder, unit for measuring the rotational speed of the stand rolls, comparison unit, output converter, controlled motor. The command to start the deceleration of the mills at the end of each pass is formed as a function of the length of the remainder of the strip on the unwinding reel and the frequency of rotation of the stand.

This device does not take into account the rate at which the metal enters the cage and, consequently, its compression. In the presence of crimping, the signal for deceleration is given prematurely, and the remainder of the strip on the unwinding reel at the time of the start of deceleration

more is needed, which leads to an increase in mill retardation and decreases in output metal. - -: -.

A device is known for an automatic, accurate, remaining rolling mill containing pulse sensors for the angle of rotation of the winders, a strip length measuring unit, a block

0 code-analog converter measuring the remainder of the strip on 4) winding coiler during deceleration, blocking measurement of rotation frequency of unwinding coiler and rolls

5 stands, an analog multiplication unit for speeds, including a calculated deceleration path, a comparison unit, an output transducer, and a controllable motor.

0

The closest to the invention in terms of economic essence and the achieved result is a device for aV: Somatic exact stop of the reversing mill, containing pulse angle sensors of winders, strip length measuring unit, decoder, unwinding winder rotation frequency measuring unit, comparator unit, output 0

oh converter, controlled., drive. In its structure, the device contains only the elements of the destructive action, which increases its accuracy. This, as well as the presence in the device of the measuring unit of rotational speed of the unwinding winder Partially eliminates the above mentioned disadvantages.

A significant disadvantage of this device is that they only allow for the reduction of the maximum rolling speed. When the rolling speed is different from the maximum, the signal to slow down the pack enters prematurely, which leads to an increase in braking time, a decrease in the output of the metal. This disadvantage is due to the fact that there is no element in the device that takes into account the actual rolling speed.

The aim of the invention is to eliminate this drawback by making the choice of the moment of the beginning of the deceleration of the mill, taking into account the reduction of the metal at any rolling speed for more | th production by shortening the retardation time and increasing the yield of the metal

The stated objective is achieved by the addition of a rotational speed measurement unit to the device.

the stand and the block for the hour rotation. Fire is proportional to the required: braking path, connected to the unit. compare.

Determining the required starting point for slowing down the mill. In dependence on the remainder of the strip on the unwinding winder and the ratio of the rotational speed of the stand and the unwinding winder, reduces the stopping time, which reduces the productivity of the mill. A reduction in the amount of metal rolled by the monogram during the retardation period also contributes to increased productivity, since the latter is usually substandard. ,

1The rotation frequency ratio block is made up of a series of schemes for comparing the signals of the angular velocity of the stand and the unwinding winder, which realize

expression

..

DGR

fa

TDe C -. the required length of the remainder of the strip on the unwinding coiler.

B is the diameter of the work rolls cage m;

 - average for the period of slowing down the diameter of the roll on the unwinding winder, m; tJ - the frequency of rotation of the rolls of the cage at the initial moment

braking, 1 / cr o - rotational speed of the unwinding winder at the initial moment of braking, 1 / s; a - acceleration

stands, m / s. The degree of accuracy of the expression implementation is determined by the number of comparison circuits.

Fig. 1 shows a block diagram of a device for an automatic exact stop system of a mill with a rotation frequency ratio block in the form of a series of comparison circuits; in fig. 2 - frequency ratio block.

The device contains sensors 1 and 2 pulses of rotation angle of the winders, the outputs of which are connected to the input of the unit 3 Length measurement, the output of which is connected to the decoder 4, the output; The latter is connected to the input of the comparator unit 5, the output of the rotation frequency block is connected to another input of the block 5, the first 5 inputs of which are connected to the output of the rotation speed roll block 7, and the second input - to the rotation frequency block 8 of the winder. The output of the comparison unit 5 is connected to the input of the output converter 9, the output of which is connected to the engine 10 of the stand.

The device works as follows. .,. . . measurement of the rotation angle of the winders

5 is produced by means of sensors. 1 and 2 pulses. After the next pass, pulses are recorded in block 3 of the length measurement, the number of which is proportional to the angle of rotation

0 reeling, winder. In the skip trace, the number of pulses, proportional to the angle of rotation of the unwinding Winder, is read from the previously recorded number.

5 The length of the strip on the unwinding unit at the beginning of the deceleration is determined by the selected discreteness. The decoder 4 in block 5 is compared with the required length of the remainder

strip, which is determined by block 6 depending on the ratio of the frequencies of rotation of the rolls of the stand and the unwinding winder, controlled respectively by blocks

5 7 and 8. At the moment of equality block 5

comparison through the output converter 9 forms a command to slow down and stop the engine 10 of the stand.

The rotation speed ratio unit 6 (see Fig. 2) contains the logic elements 11 of the functions AND, the first input of each logic element is connected to the unit 7 for measuring the rotational speed of the stand rolls, the second input is for the unit 8 for measuring the rotational speed of the unwinding winder. The outputs of all logic elements are connected to the comparison unit 5.

Each logic element 11 is activated only at a certain ratio of the frequencies of rotation of the rolls of the stand and the unwinding winder. Logic elements located in the same horizontal row operate at the same frequency of rotation of the rolls of the stand controlled by block 7, but at different values of the rotation frequency of the unwinding winder controlled by the block 8. The logic elements located in the same vertical row work at one the frequency of rotation of the unwinding winder, but with different values of the frequency of rotation of the rolls of the stand.

When any of the logic elements 11 is triggered, a signal appears at the input of the comparator unit 5, which corresponds to the required, taking into account the reduction, the length of the strip at the unwinding of the coiler to the beginning of the deceleration. The number of elements And is determined by the required accuracy of measuring the Length of the remainder of the strip.

This device allows simple and reliable means to increase the efficiency of the automatic exact stop system by reducing the braking time of the mill. This reduces the rolling time of one coil and, in addition, increases the amount of metal rolled at a steady rate, which improves the quality and yield of the product.

The device without significant costs and time can be implemented on existing mills.

Claims (3)

1. Device for automatic accurate stopping of the reversing rolling mill with winders, the coil of the sensors of the angle of rotation of the winders, the length measuring unit, the decoder, the comparator, the measuring unit of the rotational speed, the unwinding winder, the output converter, the controlled motor, and the h: You can do it because, in order to reduce the time of slowing down and increase the yield of the metal by: 66i, the moment of the start of braking of the mill, taking into account the reduction of the metal at any speed niiokaTKH, it additionally contains a block Measurements frequency B1) ascheni roll stand and the unit ratio of the rotational frequency, the first input of which is connected to the frequency measuring unit yyhOdom rotation 0 rolls of the stand, and the second input is connected to the unit for measuring the rotational speed of the razmatyyEEL winder, and the output is connected to the second input of the comparison unit. - :: - five 2 ,. The software device of claim 1, about t l.Ich a yu e so that the block ratio of rotational frequencies is made in the form of a matrix of logical elements I. 3. The device according to A.1, about tl item that output h a, 50 ua e with the measurement unit for Ann is connected to the third input of the comparator unit, and the rotation frequency ratio block contains the arithmetic code adder numbers . . FS / g / srig.e