SU978963A1 - Apparatus for stabilizing stand load ratio at die rolling - Google Patents

Description

The invention relates to the processing of metals by pressure by longitudinal periodic rolling. . Closest to the descriptive control device is the speed of the setting rollers of the periodic 1 M rolling mill, which contains systems for automatically controlling the speeds of the rolls of the setting and working stands, which include an actuator and speed sensors and drive currents, logical elements AND, NOT, keys, adder, and proportional unit drive currents, a memory device, wherein the unit for proportioning the currents with its inputs through the second and third keys is connected with the sensors of the drives of the drives of the rollers and. to the cells, the first key is connected to the current accumulator of the rollers through a memory device, the control inputs of the first and second keys are connected to the outputs of the first and second logic elements AND, and their first inputs are connected to the switch directly and through the element NOT. The drawback of the device is that the stabilization of load ratios (speeds) of the driving and working stands for the square and beam sections is characterized by significant regulatory actions that are required to be performed in fairly short periods of time. At a speed of 2 m / s, the rolling time of a square will be on average 0.3 s for the beam part — 0.6 s. The motor of the working stand has an electromechanical time constant of O, 8 s, and an electromagnetic one, O, 4 s. Therefore, even the use of an automatic control system for the speed of both the working and master stands does not allow for the timely adjustment of the load ratio. The setting of a certain average value of the velocity aggravates the influence of disturbances during the rolling of the beam part. In addition, the dynamic currents flowing through the adjustment of the rotation frequency of the ropik drive complicate the measurement of its static load, which reflects the rolling moment. Therefore, the initial load information is degraded, which is necessary to stabilize the state of the metal between the cells. In addition, the current load values are influenced by various beat disturbances with a significant random component. The aim of the invention is to increase the accuracy of the length stabilization period (and when the load of the working cell changes .. ../.-. - i. The goal is achieved by. that a device for automatic control of the speed of the master rollers of a periodical rolling mill, containing systems for automatically controlling the speeds of the rolls, respectively, of the master and working stands, having in its composition actuators of speeds and currents of the drive, logic elements AND, NOT, keys, adders, drive current proportional unit, memory, switching unit, block for determining rolling of the beam part of the roll, and the unit proportional currents with their inputs connected with current sensors of drives of rollers and stands, the first key is connected to the current accumulator of the rollers through a memory device, the control inputs of the first and second keys are connected with the outputs of the first and second logic elements AND and their first inputs are connected to the switch directly and through the NOT element, additionally contains serially connected averaging block for adjusting the magnitude of the roller drive current and a load tendency analyzer with two information and control outputs, and the input of the averaging block for the correction is connected to the output of the current proportioning block, the information output of the analyzer is connected with the input of the first key, and the control one is connected with the second input of the first logical element I, In order to increase the accuracy of one hundred ilizatsii period length, preferably at bolschoy x reduction, the device further comprises associated with second inputs of the second and third AND gates block the beam part determining the rolling of roll. FIG. Figure 1 shows a block diagram of a device for stabilizing the cess of loading of the stands during periodic rolling; FIG. 2 is a block diagram of the propelling unit; in fig. 3 is an averaging block diagram. The device contains a system of 1 automatic control of the speed of the driving and working stands. System 1 includes a speed master 2, totalizers 3, 4 speeds and currents, speed regulators 5, 6, drive 7, current and speed sensors 8, 9, drive current proportioning unit 10, drive block averaging current equalizer 11 , analyzer 12 tendencies for changing load correction, first key 13, memory 14, first logical element 15, second logical element 16, element 17, block 18 commutators for correction and information channels, rolling sensor 19 for beam section of profile, second key 20 Block 10 is proportional neither its own inputs are connected via the key 2O with the sensor drive current sensor 8 and through the third key to the working stand current sensor, and the output through the averaging unit 11 is connected to the analyzer 12 of the trend of the change correction load of the master stand, whose information output through the key 13 and the memory device 14 is connected to the adder 5, and the logical element AND 15 inputs are connected to the control output of the analyzer 12 and the output of the switching unit 18, and the output to the control input of the key 13, the second element. AND 16, as well as the third ( on the black These are not shown) with their inputs connected with the rolling sensor 19 of the beam section of the profile and, through element 17, NOT with the switching unit 18, and the output with the control input of the key 2O. The unit 1O proportional loadings of the drives of the stand and the rollers, which calculates the value of the correction current of the master rollers, and consists of the most important 21,. an adder 22, a setting unit 23 of a predetermined ratio of drives, current sensors of a setting driver 8 and a worker 241, keys 20 and 25. The first input of the multiplication unit 21 receives a signal from the setting unit 23, and the second input receives the output signal of the key 25, information the input of which is associated with a sensor 24 current drive rolls. The output of the multiplication unit is fed to the first input of the adder 22, the second input of which receives a signal from the key 2O, whose information input is connected to the sensor 8 current of the driving rollers, and the control input of the key 2O receives a signal from the logical element 16. the control signal is generated by a similar circuit of the main drive of the rolls. The output signal of the current correction of the driving rollers of the adder 22 is the output signal of the block 1O. During the rolling process, the rolling sensor 19 of the beam part using logic circuits opens the keys 20 and 25 for 6 seconds, and at the output of the unit U, during rolling of one string, with a interval of 0.3 seconds, 14.15 / values appear amendments, which corresponds to the number of beam sections. During the rolling of a single beam section, which is relatively short (about 1 m), the currents of the first stand and the rollers practically do not change with, but between the adjacent beam sections on the same roll and the rolls such deviations are significant. The output signal of block 10 is fed to the input of averaging unit 11, which consists of a set value block 26, coefficients " Jr and 1 - -, multiplication blocks 27 and 28, adder 29 and memory 30. The first input of multiplier 27 receives a signal block 1O, to the second input - from the block .26, and the output is fed to the first Yohod of the adder 29. To the first input of the multiplying unit 28, the output signal of the AOR memory is received, to the second input - the signal from the block 26 and the output to the second input is the sum of a torus 29, the code of which is connected to the memory troystvom LP whose output signal corresponds to the entire vkodu unit 11, When applied to i. At a signal step Oz P-t, the first input of the multiplication unit 27 multiplied by qf is fed to the first input of the adder 29, and the second input is the value obtained at the output of the adder 4 at the preceding step -1 and multiplied by ua / J-T which is stored in the DA unit. For the next i + 1-th step, the D L Pi value obtained at the 1-st step is multiplied by 1-TC and determines the process history. The value of 0.62 when rolling the Rizhsk axis indicates a relatively low level of interference when rolling one rod. Thus, block 6 calculates the average value of the po3 edit current when rolling one rod containing 14–15 times. The -Jf value is in the range of 0.55-0.75 for the entire assortment. The device works as follows. When metal enters the cage of the pressing rollers, the automatic speed control system 1 provides the feed mode with the speed set by the setting device 2 and the load mode (current), which is provided by speed controllers 5, 6 and information current from the sensors 8. and speeds of royik . When the workpiece is fed into the working stand, a similar regulation of the parameters of speed and current of the main drive takes place at the square rolling section. When rolling a beam part with large reductions, the load current of the main drive through a hard metal and sharply increases: the load current of the rollers, the load proportioning unit 10 calculates the value of the correction current of the drive rollers, which is averaged by the block 11 both during rolling of one multiplicity and between adjacent multiplicities, and the analyzer 12 calculates the tendency of the load ratio between the working and master stands. The inputs of block 10 receive signals about a predetermined ratio of loads of the drives () and loads of the drives of the stand jj and the rollers Зр, when no control action is taken on the drives. This is provided by the key 20, the element AND 16 and the element NOT 17. The signal for the measurement occurs according to the resolution from the rolling sensor 19 of the beam part, as the conditions are. Rolling is characterized by significant instability and the effect of disturbances is greatest. At the output of the unit Yu, the correction of the load of the rollers is determined from the relation: A (}. Averaging is performed on each beam section of the roll (14-15 sections in total on one rod). The analyzer 12 determines the intensity of change of the correction, for example, by an iterative procedure, when the process history and its updating with a certain weighting factor -.ft are taken into account. Then for the -1 -th period: Vr-VA -p pip. - Aactivation of the correction for / l-that where Df is the period; 3f i-average correction value for i -1 periods of history - the new value of the correction for the i-th p In the period, the averaged recorded value is fed to the information input of the key 13, and to the control one — the signal from the commutation unit 18. When the signal from block 18 is supplied, the contents of block 12 are written to the memory 14. The rate of change of the averaged correction for the time interval is also calculated. / l. If the obtained value is very small or very large, there is no signal at the output control, information from block 12 through key 13 is not received in memory 14. Minimum value of the rate of change of the correction composition It is 5 a / s and the maximum is no more than 50 a / s. When the signal from the switch 18 unit to the second input of the logic element 15 is faded, the information output of the unit 12 is copied to the storage device 14. The cage of the drive rollers is corrected as the task in the drive current control loop has changed. noija will not be provided for a given roller load. At the same time, the measurement circuit of the drive currents is disabled (the key 20 is not included); The sensor 19 for the presence of rolling of the beam part is implemented as a force sensor with detection of the moments of increase and decrease of forces. It can be implemented in the full threshold scheme. The device allows increasing the storage in the driver stand. The magnitude of the backpressure, selected for rolling a given profile dimension, is adjustable and is ensured constant during rolling of the beam section of the profile. Maintaining a constant load ratio ensures that the state of the metal between the master and the working cells is constant, and therefore noBbniiae with stabilization accuracy dLin short to Stabilize load ratios just for beam sections of periodic profiles 1FIVODIT to a certain destabilization of this ratio in the square rolling sections, Due to the fact that the influence of disturbances on Quodrate is much less than on the beam part (identical to the deformation conditions in the working and master cage), this system allows can improve the accuracy of the length of the periods. Regulatory effects can be applied both to the master and to the working stand. In the latter case, the control range is expanded, but an automatic control system of the speed of the rolls of the working stand is provided. The stabilization of the dyn multiplications allows one to get rid of the marriage due to non-observance of length tolerances. This eliminates the need to rebuild the saws for hot cutting. Formula of the invention 1. A device for stabilizing the ratio of loads of the stands during periodic rolling, which contains systems for automatically controlling the speeds of the rolls of the setting and working stands, which include the setting devices, adders, regulators, speeds, currents, speed sensors, and drive currents , the drive current proportional unit, memory, device, keys, logic gates, AND, NOT, switching unit, the current proportional unit entering the inputs through the second and third keys connected to the sensor The current drives the rollers and the cage, the first key is connected to the current adder of the rollers through a storage device, the control inputs of the first and second keys are connected to the outputs of the first and second logic elements AND, and their first inputs are connected to the commutator directly and through the element NOT , characterized in that, in order to stabilize the length of the period with varying load on the drive of the working stand, it additionally contains a series of averaged means for correcting the value of the drive roller current and a trend analyzer and changing the ratio of loads with two outputs - information and control, the input of the averaging block of the correction is connected to the outputs of the current proportional block, the information output of the analyzer is connected to the input of the first key, and the control input of the first logical element I. 2. A device according to claim 1, in which case, in order to increase

the accuracy of stabilizing the dtpl of the period, predominantly with large shrinkings, it additionally contains associated with the second inputs of the second and third logic elements AND a block of definition 5 for rolling the beam part of the roll,

3, the device according to claim 1, characterized in that the drive current proportioning unit comprises drives of current ratio associated with the inputs of the multiplier unit O set the load ratio and through the first key a drive current sensor, the output of the multiplier unit connected to the first input of the adder, the second input of which the second key is connected, c5. roller current sensor.

4. The device according to claim 1, wherein the averaging unit of the correction current magnitude of the drive roller drive contains the first multiplication unit, the output of which is connected to the first input of the adder, its output through the storage device and the first input of the second multiplication unit is with the second input of the adder, and the second inputs of the multiplication units are connected to the block of constant coefficients.

Sources of information taken into account in the examination 1. USSR author's certificate in application No. 2912276, cl. In 21 837/00, 1980.

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Claims (4)

Claim 1. A device for stabilizing the ratio of the load of stands during periodic rolling, containing systems for automatically controlling the speed of the rolls, respectively, the master and the working stand, which include master devices, adders, regulators, speeds, currents, speed sensors and drive currents, a unit for proportionalizing drive currents, storage , device, keys, logical elements AND, NOT, (switching unit, and the unit for proportioning the currents with inputs through the second and third keys is connected to the current sensors of the drives ro ikov and stand, the first key through the storage device is connected to the adder of the current rollers, the control inputs of the first and second keys are connected to the outputs of the first and second logical elements And, and their first inputs are connected to the switch directly and through the element NOT, characterized in that, in order to stabilize the period length with a changing load on the drive of the working stand, it additionally contains a series-connected unit for averaging the corrections of the current value of the drive of the rollers and an analyzer of a trend in the ratio loads with two outlets - and the control information, the input of the averaging correction unit coupled to the outputs of the proportioning currents analyzer data output connected to the input of the first switch, and the control output - to a second input of the first logic element I. 2. The device according to π. 1, the fact that, in order to increase the accuracy of stabilization of the period length, mainly with large reductions, it additionally contains associated with,. the second inputs of the second and third "logical elements AND block determining the rolling of the beam part of the roll, 3. The device pop. 1, characterized in that the proportionalization unit of the drive currents comprises a load balancer connected to the inputs of the multiplication unit and a current sensor of the drive of the rolls through the first key, the output of the multiplication unit being connected to the first input of the adder, the second input of which is connected through the second key, s! current sensor rollers. 4. The device according to π. 1, characterized in that the averaging unit for adjusting the magnitude of the current of the drive of the rollers contains a first multiplication unit, output 5 of which is connected to the first input of the adder, its output through the storage device and the first input of the second multiplication unit - with the second input of the adder, and the second inputs of the blocks multiplications are connected with a block of constant coefficients.