RU1795919C - Device for diagnosing condition of rolling mill equipment - Google Patents

Description

The following calculations of the autocorrelation functions and the spectral density functions of the rolled profile and finished strip profiles, as well as the current waveforms of the coiler, showed that the portion of the vibrations of the mill equipment from tension fluctuations during rolling is 30-30%, and the proportion of the longitudinal variation in the thickness of the rolled coils the longitudinal thickness variation of the finished strip is about 10-20%.

The purpose of the invention is to expand the boundaries and increase the accuracy of diagnostics on cold rolling sheet mills by taking into account the influence of disturbances from fluctuations in tension and thickness of the rolled strip.

A known formula for calculating the natural frequency of an oscillatory system.

,

utekv REKV where gpkv t - body weight (system);

Req 0.4 R (P-force applied to the system) - system compliance.

This goal is achieved in that in a device containing a unit for measuring vibration parameters, a unit for determining a diagnostic situation, a bandpass filter unit, a rolling speed sensor, a threshold unit for blocking, a rolling speed level coding unit, a setpoint input unit, first and second switches, a harmonic signal converter potential, a comparison unit, indication and registration units, a coding unit for the product of the thickness of the rolled strip by the tension and a decoder, from which Ator enters proximate vibration signal parameters.

In FIG. 2 is a block diagram of an apparatus for diagnosing equipment condition of a strip rolling mill; in FIG. 3 is a structural diagram of a decoder.

The device comprises a rolling speed sensor 1, a threshold element block 2, a vibration parameter measuring unit 3, a rolling speed level coding unit 4, a diagnostic situation determination unit 5, a key 6, a bandpass filter unit 7, a coding unit 8 for the product of the thickness of the rolled strip by the tension, a decoder 9, a setting input unit 10, a second switch 11, a first switch 12, a harmonic signal to potential converter 13, a comparison unit 14, an indication unit 15, a registration unit 16.

The output of the rolling speed sensor 1 through the threshold element block 2 is connected to the inputs of the rolling speed coding block 4, the outputs of which are connected to the inputs of the decoder 9, the outputs of the coding block 8 of the product of the thickness of the rolled strip by the tension are connected to the other inputs. An example of a structural diagram of a decoder 9 at three levels of coding of the rolling speed and two levels of coding of the product of the thickness of the rolled strip by the tension is shown in FIG. 3. The decoder is a set of AND gates, the number of which is equal to the product of the number of levels of coding of the rolling speed and the number of coding levels of the product of the thickness of the rolled strip by tension. Moreover, each output of the rolling speed level coding unit 4 is connected to the first inputs of two logical elements AND, each output of the encoding unit 8 of the product of the rolled strip thickness and tension is connected to the second inputs of three logical elements I. The outputs of the logical elements And, which are the outputs of the decoder 9 are connected to the control inputs of the switch 12 of the bandpass filter unit and the switch 11 of the input setpoint unit, to the information inputs of which the outputs of the setpoint input unit 10 are connected. The output of the vibration parameter measuring unit 3 is connected to the information input of the key 6, to the control input of which the output of the diagnostic situation determination unit 5 is connected. The output of the key 6 is connected to the input of block 7

bandpass filters, the outputs of which are connected to the input of the information inputs of the switch 12, the output of which is through the harmonic signal converter 13 to the potential at the first input of the comparison unit 14. The output of the switch 11 is connected to the second input of the comparison unit 14. In addition, the information input of the registration unit 16 is connected to the output of the harmonic signal converter 13, and the input of the display unit 15 and the control input of the registration unit 16 are connected to the output of the comparison unit 14.

The device operates as follows. zom.

From the output of the vibration parameter measuring unit 3, the signal is supplied to the information input of the key 6. If there is an enable signal from the control input key 6 from the block 5 to determine the diagnostic situation (for example, if there is

band in the mill stand) the signal from the output of key b goes to the input of the bandpass filter block. The bandpass filter unit 7 selects a spectrum of frequencies whose amplitudes characterize the deviation of the state of the equipment from the operating mode and consists of a set of bandpass filters tuned to those characteristic of a given mill at a given rolling speed. The value of the rolling speed at each time point is determined by the rolling speed sensor 1. The signal of the rolling speed sensor 1 is supplied to the inputs of the block 2 of threshold elements. The number of threshold elements is determined by the number of selected rolling speed ranges, and each is tuned to a specific voltage with a dead band set. In this case, the entire range of possible rolling speed values is covered. The signals of the threshold elements, received at the input of the block of coding of the rolling speed levels, after the logical conversion, go to the inputs of the decoder 9. The logic of the conversion of the signals of the decoder 9 is shown in the correspondence table of the inputs - outputs of the block 9, where A, B, C, D, D are the inputs and E, F, 3, K, L, M are the outputs. At the other input of the decoder 9, a signal is received from the coding unit 8 of the product of the thickness of the rolled strip by the tension. The thickness of the rolled strip and the tension during rolling are selected in accordance with the rolling conditions in each pass, and the number of coding levels is determined by the condition that the entire possible range of the product of the thickness of the rolled strip by the tension possible on this rolling mill is covered. The signals from the two inputs are logically multiplied by the element And, and the output signal is supplied to the control inputs of the switches 11 and 12. The switches consist of a set of keys, the number of which is equal to the product of the number of coding levels of the rolling speed and the number of coding levels of the product of the thickness of the rolled strip by the tension.

The output signals of the decoder 9, arriving at the control inputs of the switches 11 and 12, switch the passage through the switch 12 of the corresponding frequency of the harmonic signal, and through the switch 11 - setting the acceptable signal level specified by the settings input unit 10.

The signal from the output of the switch 12 after converting the harmonic signal into a potential converter 13 is fed to the first input of the comparison unit 14,

the second input of which receives the setpoint signal from the output of the switch 11.

In the comparison unit 14, the set value of the allowable signal value from the setpoint input unit 10 and the vibration signal value of the converter 13 are compared, and when the set value is exceeded, the excess signal is displayed in the display unit 15. By the same signal, the signal value is recorded in the block 16 registration, which is received from the Converter 13 to the information input of the block 16. ...

. When the speed or the rolling mode changes (for example, when the thickness of the rolled strip or (and the tension) changes at the first input of the comparison unit 14, the vibration converted to a potential signal at a frequency corresponding to the new speed value appears

rolling and the product of the thickness of the rolled strip under tension. At this time, at the second input of the comparison unit 14, the signal value corresponds to the permissible vibration level in these ranges of rolling speeds and the product of the thickness of the rolled strip by the tension.

Claims (1)

SUMMARY OF THE INVENTION A device for diagnosing a condition of equipment of a rolling mill, comprising a vibration parameter measuring unit, a diagnostic situation determination unit, a bandpass filter unit, a rolling speed sensor, a threshold element unit, a rolling speed level coding unit, a setpoint input unit, two switches, a harmonic converter signal to the potential, the comparison unit, the display and registration blocks, and the diagnostic situation determination unit is connected to the control input key Block measurement parameters vibration is connected to the key information input, the key output is connected to the input of the bandpass filter block, the rolling speed sensor is connected to the inputs of the threshold element block, the outputs of which are connected to the inputs of the rolling speed level coding block, the control inputs of the first and second switches are interconnected, information inputs the first switch is connected to the outputs of the bandpass filter block, the control inputs of the second switch are connected to the outputs of the setpoint block, the output of the first switch is single to the input of the harmonic signal to potential converter, the output of which is connected to the first input of the comparison unit and the information input of the registration unit, the output of the second switch is connected to the second input of the comparison unit, the output of which is connected to the input of the display unit and the control input of the registration unit, characterized in which, in order to expand the boundaries and improve the accuracy of diagnosis by taking into account ABOUT 5ft 10 20 30 40 50 60 70 80 F.fo FIG. I the influence of fluctuations in the tension and thickness of the rolled strip, it is equipped with a coding unit for the product of the thickness of the rolled strip and the decoder, the inputs of which are connected to the outputs of the block for coding the speed levels and the coding unit for the product of the thickness of the rolled strip and the outputs to the control switch inputs .. and i. i l Fie.Z