SU576129A1 - Strip thickness control system - Google Patents

Description

(54) NOLOS THICKNESS REGULATION SYSTEM

one

The invention is different from the field of automation of the process of rolling a strip, more precisely to devices for automatically maintaining a constant thickness of rolled metal and can be used in devices for the manufacture of a product by rolling between rolls.

A system is known for adjusting the thickness of a strip irokatyvnaya on a continuous mill-COLD COLOR.

The known system for adjusting the strip thickness contains a coarse thickness regulator, the output of which is connected to the engine, coupled with the pressure mechanism of the rolls of the first stand, the device for limiting the interstand tension of the strip, the inputs of which are connected to strain gauges installed between the mill stands, and the outputs with engines connected to the pressure mechanisms of the rolls and subsequent mill stands and with the first inputs of the corresponding control circuits, roll motors connected to the outputs of the control circuits, tachogenerators, kinemat cally associated with the motor of the rolls, and micrometers, the first of which is arranged between the first and second stand of the mill and connected to the input of the coarse regulator tolschiiy and second micrometer mounted on the outlet of the last mill stand and is connected to one input of a comparison circuit.

The coarse adjustment of the strip thickness is carried out by the pressure screws of the first stand according to a micrometer signal set at the exit of this stand.

A fine adjustment of the thickness of the hair occurs by changing the tension of the strip in the area between the last two cells but a micrometer signal set at the output of the last cell.

The signal of this micrometer, proportional to the thickness of the strip, is fed to the input of a precise strip thickness regulator, where it is compared with a given value.

Depending on the sign and size of the signal

The errors are proportional to the speeds of the engines of the main drives of the mill, which leads to an increase or decrease in the tension of the strip between the last stands of the mill and, accordingly, to a decrease or increase in the thickness of the hair.

The disadvantage of this adjustment system is the strip out of the mill having a longitudinal thickness variation beyond the tolerances in sections longer than the transorting path.

The purpose of the invention is to improve the accuracy of reglirovaniyaolos, rolled on a continuous cold rolling mill. The goal is achieved by the fact that a comparison circuit is additionally introduced into the control system, the first input of which is connected to the output of the adjustable trip block, and the second to the output of the tachogenerator of the last stand; an amplifier whose input is connected to the output of a single comparing circuit, its first output is connected to the second inputs of the speed control motors of the stands of the stand, preceding the last stand, and its second output is connected to the second input of the engine speed control circuit of the last stand of the mill, and the integrating amplifier, the input of which is connected to the output of the comparison circuit, and the output to the tachogenerator of the last stand of the mill, as well as by the fact that one of the inputs of the adjustable throwing unit is connected to the tachogenerator with a trace; Twa izmenepn sekundgyugo volume.

The drawing shows a block diagram of a system for regulating a thick strip rolled on a continuous, four-cell mill, and cold rolling mill.

The strip adjustment system contains: a coarse regulator of thickness 1, the output of which is connected to the engine 2, connected to the loading mechanism of 3 rolls 4 of the first mill stand, device 5 of the end section of the interstand tension strip, the inputs of which are connected with strain gauges 6 installed between the stands of the mill , and the outputs - with the engines 7 connected to the pressure mechanisms 8 of the rolls 9 of the subsequent stands of the mill and with the first inputs of the respective control circuits 10, the speed of the motors 11 of the rolls 9, tachoherators 12, of the engines II of the rolls 9, mnkrol1etry 13 n 14, the first of which ustanovlep between the first and second cage Etap nodklyuchen and to the input of the coarse regulator 1 tolschnny and second micrometer ustanovlep H; I mill output and is connected to one of the inputs of circuit 15 sravieni.

The strip thickness control system also includes a device 16 for measuring the seculate volume at the mill inlet, a variable drive unit 17, the first and second inputs of which are connected to the outputs of the device for measuring its volume and other inputs corresponding to tachogerators of the 12 mill stand roll motors preceded by 1 Lastly, an additional circuit 18, the nerve input of which is connected to the output of the adjustable delay unit 17, the second input to the tachogenerator of the 12 double rolls of the empty cage stapler, amplifier 19, whose input is equipped with the output of the circuit compared to 18, and the nerve output to the second inputs of the control circuits 10, the speed of the roll mill engines of the mill stand and the second output to the second input of the engine speed control 10 and an integrated installer 20, the input of which is connected to the output of circuit 15, and the output to the tachogenerator of the 12-hour stand.

The device 16 for measuring the second volume at the mill input includes the following

rollers 21, tachoheperator 22, kinematically connected with follower rollers 21, micrometer 23 and unit of conciliation 24, nerve input of multiplication unit 24 is connected to micrometer 23, and the second input is connected to output of tacho generator 22. The bar also shows unwinder 25 and winder 26 .

The condition for the presence of second volumes of metal at the mill inlet and outlet, taking into account the fact that the broadening bands at the inlet and outlet are almost odiakov, has the form

V, H, V.H Q,

where vq and yao

-speed n thickness of the metal at the entrance to the flocks;

1/5 and I, - the speed and thickness of the metal leaving the mill; Q is the second volume of metal. Due to the fact that the second volume of metal entering the last stand of the etaia within the limits of the speed of this stand does not depend on it, the thickness of the strip pa of the mill output is inversely normal to the speed and is expressed by

H, -.

 V h

Given the measured second metal volume,) as an example due to a change in the thickness of the rolled strip, the Q value will be incremented and will become equal to Q + AQ. At a constant speed of the metal coming out of the mill, its thickness will not increase.

W.,

U :,

In order to maintain the thickness of the strip at the mill outlet, it is necessary to maintain a constant ratio of its volume to the last stand and the speed of the metal exit from this stand, i.e.

, „: Const,

where Yadts is the specified value of the strip thickness at the output of the stack.

The system for adjusting the thickness of the nose works as follows.

The Q value, proportional to the second metal volume at the mill outlet, is measured with the help of follower rollers 21 and associated tachogenerator 22, as well as with a micrometer 23 installed between decoiler 25 and the first mill stand.

The output of the tachogenerator 22 and the micrometer 23 are multiplied by a block of 24 signals, and the output of which is acted upon by a signal, which is ironion Q.

B) A single signal from multiplier 24 supplies an adjustable delay unit 17, supported by the voltage of tacho generator 22, to determine the transport delay from the micrometer 23 installed at the entrance to the mill to the first stand.

and the tachometer stress 12 of all the stands, except the last, for determining the transport delays in the sections between the stands.

An adjustable lag unit 17 delays the signal of the second volume of metal by the time of transport lag from the micrometer 23 installed at the mill entrance to the last mill stand.

The output signal of the adjustable delay unit 17 is compared by comparison circuit 18 with the voltage of the tacho generator 12 of the last stand of the mill and their difference is fed to the amplifier 19.

The output signal at the first output of the amplifier 19 acts on the speed control mechanisms 10 of the stands engine preceding the last, and the output signal on the second output of the amplifier 19 affects the speed control circuit 10 of the last stand in the direction that maintains the ratio of the second volume of metal entering the last stand of the camp, to its speed.

In this case, the amplifier 19 performs sequential regulation of the speeds of the stands preceding the last, i.e., the ratio of the speeds of these stands during the adjustment process remains unchanged.

To adjust the thickness of the strip at the exit of the mill with a given value, the gear ratio of the tachogenerator 12 of the last stand is corrected with an integrating amplifier 20, the output voltage of which operates in the excitation circuit of the tachogenerator 12 of the last stand.

The input signal of the integrating amplifier 20 is the deviation of the strip thickness at the mill input from the set value Yadz, obtained by comparing this value with the actual thickness Nd of the strip at the mill output, measured with a micrometer 14 installed between the last mill stand and the coiler 26.

Thus, due to the introduction of an additional comparison circuit and an integrating amplifier, as well as the introduction of these inter-element connections, the proposed system allows an increase in the accuracy of the strip thickness control.

Claims (2)

1. A system for adjusting the strip thickness, containing a coarse thickness regulator, the output of which is connected to the engine of the first roll stand mechanism, a device for limiting interstand tension of the strip, the inputs of which are connected to strain gauges installed between the mill stands and the outputs mechanisms by rolls of subsequent stands of the mill and with the first inputs of the corresponding control circuits for the motors of the rolls, the roll motors, connected to the outputs of the control circuits, tachogenerators, kinematically connected with roll motors, micrometers, the first of which is installed by the first and second mill stand and connected to the input of the coarse thickness regulator, and the second micrometer is installed at the output of the last mill stand and connected to one of the inputs of the comparison circuit, a second volume measuring device at the mill entrance, containing followers, a tachogenerator kinematically connected with followers, a micrometer and a multiplication unit, the first input of the multiply unit connected to the micrometer, and the second to the output tachogenerator and the second output of the device, and an adjustable lag unit, the first input of which is connected to the output of the multiplication unit of the second volume measuring device at the mill input, the other outputs, respectively, with tachogenerators of the stands with ana, predschestvuyuschih latter, characterized in that, for the purpose of accuracy the Enhance controlling the thickness of the strip, an additional comparison circuit is introduced into the system, the first input of which is connected to the output of the adjustable delay unit, and the second to the output of the tacho generator of the last stand, the amplifier whose input is connected to the output of the additional comparison circuit, its first output is connected to the second inputs the speed control circuits of the mill stands of the mill that stand before the last stand, and its second output, with the second input of the speed control circuit of the main motor of the last stand, and the integrating amplifier in od which is connected to the output of the comparison circuit and output to the tachogenerator last mill stand. 2. The control system of p. 1 differs from the fact that, in order to account for the transport delay on the way from the device for measuring the second volume to the first stand The mill, one of the inputs of the adjustable lag unit, is connected to the tachogenerator of the follower rollers of the second volume measuring device. Information sources, taken into account in the examination 1. Kleshko O. B. “Automatic control of strip thickness during rolling, ed. Metallurgists, .M., 1966. p. 36-39, fig. sixteen.