JP3669820B2 - Tandem rolling mill speed control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a speed control device for a tandem rolling mill that constitutes a rolling facility such as steel, and in particular, in a facility that continuously joins rolled material pieces vertically on the entry side of the rolling stand and continuously rolls the rolling stand, the manual speed of the rolling stand. The present invention relates to a speed control device for a rolling mill provided with correction means.
[0002]
[Prior art]
FIG. 7 shows a stand arrangement of a tandem rolling mill and a general speed control system of an electric motor that drives each stand. Here, as an example, a rolling mill composed of four rolling stands F1, F2, F3, and F4 arranged in tandem will be described, and the description will be made on the assumption that the stand F4 is a final stand from which the final rolled product P is discharged. . In order to operate and stop the electric motors M1, M2, M3, and M4 that individually drive the rolling stands F1, F2, F3, and F4 in synchronism as a whole, the master speed calculation device 10 includes the rolling stands F1, F2, F3, and F3. The master speed Sm of the whole rolling mill is given to the speed control device of F4. Stand speed setting devices 21, 22, 23, 24 for determining the speed ratio between the rolling stands output stand speed ratios Ss1, Ss2, Ss3, Ss4 predetermined for each rolling material, and multipliers 31, 32, At 33 and 34, the target speeds Ns1, Ns2, Ns3 and Ns4 of the own stand are determined by multiplication with the master speed Sm. The stand speed correction devices 41, 42, and 43 are provided in the three stands F1 to F3 excluding the final stand F4, and the above-described target speeds Ns1, Ns2, and Ns3 are input as the first input amounts. The second input amount of each stand speed correction device 41, 42, 43 is input from the speed correction amount calculation devices 61, 62, 63. The motors M1, M2, and M3 are speed-controlled through speed control devices 51, 52, and 53 based on the speed reference output from the stand speed correction devices 41, 42, and 43. The speed of the motor M4 of the final stand F4 is controlled by the speed controller 54 with the target speed Ns4 output from the multiplier 34 as a speed reference.
[0003]
Speed correction amount calculation devices 61, 62, and 63 that give second input amounts to the stand speed correction devices 41, 42, and 43 are a manual correction amount output device 2, a limiter 3, an automatic correction amount output device 4, a limiter 5, and It consists of an adder 6. The adder 6 of the speed correction amount calculation devices 61 and 62 is a three-input type, and the manual correction amount from the manual correction amount output device 2 is input to the first input terminal through the limiter 3 and is input to the second input terminal. The automatic correction amount from the automatic correction amount output device 4 is input through the limiter 5, and the output correction amounts of the speed correction amount calculation devices 62 and 63 of the next stage (adjacent downstream) are respectively input to the third input terminal as feedback amounts. Entered. The adder 6 of the speed correction amount calculation device 63 is a two-input type, and the manual correction amount from the manual correction amount output device 2 is input to the first input terminal through the limiter 3 and is automatically input to the second input terminal. The automatic correction amount from the correction amount output device 4 is input through the limiter 5. The automatic correction amount output device 4 outputs a correction amount calculated through an automatic control system such as AGC (automatic plate thickness control) or looper control.
[0004]
FIG. 8 is a block diagram selectively showing a speed control system belonging to the intermediate rolling stand F2 among the speed control systems of the tandem rolling mill of FIG. The description of the basic operation of the apparatus shown in FIG. 8 is omitted because it is the same as that shown in FIG. 7, and the manual correction amount output apparatus 2 will be mainly described here.
[0005]
The internal block diagram of the manual correction amount output device 2 shown in FIG. 8 shows a specific example, and outputs a positive or negative speed correction amount Mn according to the operation time of the manual correction operator 2a. When the manual correction operator 2a performs notch operation on the speed increasing side, the speed increasing contact 2aa is closed, the positive unit manual correction amount ΔV is read from the storage device 2b, and is supplied to the manual correction amount calculating device 2e via the adding unit 2d. . Similarly, when the manual correction operation unit 2a is notched to the deceleration side, the deceleration contact 2ad is closed, the negative unit manual correction amount −ΔV is read from the storage device 2c, and is supplied to the manual correction amount calculation device 2e via the addition unit 2d. give. The manual correction amount calculation device 2e receives the acceleration unit manual correction amount ΔV or the deceleration unit manual correction amount −ΔV while the material to be rolled is caught in its own stand (hereinafter referred to as “load on”). Then, this is integrated over time to obtain a manual correction amount Mn for the own stand, which is set as a manual speed correction amount Mnx through the limiter 3 and is set as a speed correction amount Sc from the speed correction amount calculation device 62 through the adder 6, and the stand speed correction. The device 42 is given as a second input quantity.
[0006]
The manual correction amount calculation device 2e resets the manual correction amount Mn to zero in a stepwise manner in preparation for rolling of the next material to be rolled when the material to be rolled comes out of the stand (becomes load-off). Has no influence on the material to be rolled since the load is off.
[0007]
FIG. 9 shows an example of a change state of the manual correction amount Mn by the manual correction operation during normal rolling. FIG. 9 shows that the manual correction amount Mn is formed by time integration in the positive or negative direction during the acceleration or deceleration operation by manual correction, and when the manual correction operation is canceled, the manual correction amount Mn is constant. It is shown to hold a value. As shown in the figure, the manual correction amount Mn does not exceed the limit value Slm indicated by the broken line, and is reset to zero every time material is lost, that is, every load-off.
[0008]
[Problems to be solved by the invention]
The problems of the above-described conventional rolling mill speed control device will be described with reference to FIG. In recent years, a technique has been established in which a material to be rolled is joined to a plurality of material pieces and continuously rolled as a long product before entering the rolling mill. FIG. 10 shows a continuous rolling of such a material to be rolled. It is the figure which showed the change of the manual correction amount Mn in the case.
[0009]
In the case of continuous rolling, since the material is continuously caught in the rolling stand, the manual correction amount cannot be reset to zero between materials, and manual correction is performed by continuing the rolling process for a long time. It shows that the quantity Mn can exceed the limit value Slm. Time To is the time when the manual correction amount Mn reaches the limit value Slm. Conventionally, zero reset is not performed because of the idea that if the manual correction amount Mn is zero-reset stepwise at the timing when the joint point passes, a rapid change in speed occurs and clearly affects the front and rear materials. .
[0010]
Therefore, in the case of continuous rolling, the manual correction amount Mn reaches a limit value in some of the materials to be rolled, leading to a situation where the function of manual speed correction cannot be fully exhibited.
[0011]
An object of the present invention is to provide a speed control device for a tandem rolling mill capable of always performing manual speed correction without the manual speed correction amount reaching a limit value even in continuous rolling.
[0012]
[Means for Solving the Problems]
In order to solve the above-mentioned object, the invention according to claim 1 is a speed control device for a tandem rolling mill that rolls a material to be rolled formed by joining a plurality of material pieces to be rolled vertically through a rolling stand having a tandem arrangement. The first means for automatically setting the speed reference of each rolling stand, and while the material to be rolled is bitten in the rolling mill for the rolling stand excluding the final rolling stand, the time reference with respect to the speed reference is performed manually. A second means for adding a positive or negative correction amount that increases as time elapses, and a third means for zero-clearing the correction amount at a predetermined rate at the timing at which the joining point of the rolled material pieces passes through the rolling stand to be corrected. It is characterized by comprising.
[0013]
The invention according to claim 2 is a speed control device for a tandem rolling mill that rolls a rolled material formed by joining a plurality of rolled material pieces vertically in a tandem rolling stand. While the material to be rolled is caught in the rolling mill for the first stand for automatic setting and the rolling stand excluding the final rolling stand, the positive or negative value increases with time with respect to the speed reference by manual operation. A second means for adding a correction amount; and a third means for clearing the correction amount to zero at a predetermined rate at a timing when a predetermined time has elapsed from the time when the manual operation for correcting the speed reference is stopped. It is characterized by that.
[0014]
The invention according to claim 3 is a speed control device of a tandem rolling mill that rolls a rolled material formed by joining a plurality of rolled material pieces vertically in a tandem-arranged rolling stand. While the material to be rolled is caught in the rolling mill for the first stand for automatic setting and the rolling stand excluding the final rolling stand, the positive or negative value increases with time with respect to the speed reference by manual operation. The second means for adding the correction amount, the third means for zero-clearing the correction amount stepwise at the timing when the joining point of the rolled material pieces passes through the rolling stand to be corrected, and the timing at which the joining point passes And a fourth means for adding, to the speed reference, a speed change corresponding to the correction amount output by the second means until just before.
[0015]
The invention according to claim 4 is a speed control device for a tandem rolling mill that rolls a material to be rolled formed by joining a plurality of material pieces to be rolled vertically through a rolling stand having a tandem arrangement. While the material to be rolled is caught in the rolling mill for the first stand for automatic setting and the rolling stand excluding the final rolling stand, the positive or negative value increases with time with respect to the speed reference by manual operation. A second means for adding a correction amount; a third means for zero-clearing the correction amount in a stepwise manner at a timing when a predetermined time has elapsed from the time when the manual operation for correcting the speed reference is stopped; and a correction amount And a fourth means for adding, to the speed reference, a speed change corresponding to the correction amount output until the last time when the second means is cleared to zero. It is intended.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
[0017]
<Embodiment 1>
FIG. 1 is a block diagram showing an embodiment of a speed control apparatus according to claim 1. In FIG. 1, the same or similar components as those in FIGS. 7 to 8 are denoted by the same reference numerals, and redundant description thereof is omitted. Here, only the speed control system belonging to the rolling stand F2 is shown. 1 is characterized in that a manual correction amount output device 20 having a manual correction amount clear device 2f is provided instead of the manual correction amount output device 2 of FIG.
[0018]
The manual correction amount clearing device 2f inputs the joint point passing signal 2g and the manual correction amount Mn that are activated when the joint point of the material to be rolled passes through the rolling stand F2, and the rate clear is performed at the timing of passing the joint point. The amount ΔC1 is given to the manual correction amount calculation device 2e. The manual correction amount calculation device 2e clears the manual correction amount Mn to zero at a rate corresponding to the rate clear amount ΔC1. The joining point passing signal 2g is a tracking device that estimates the passing point of the rolling stand by tracking the joining portion by, for example, integrating the traveling speed of the material with time starting from a time point representing the joining timing obtained by the joining processing device. Can be obtained.
[0019]
The manual correction amount calculation device 2e in the apparatus of FIG. 1 receives an acceleration unit manual correction amount ΔV or a deceleration unit manual correction amount −ΔV from the storage device 2b or the storage device 2c while the load of the own stand is on. Then, this is integrated, a manual correction amount Mn for the own stand is obtained and output, and the manual speed correction amount Mnx is given to the stand speed correction device 42 via the limiter 3 to perform manual speed correction.
[0020]
FIG. 2 shows a change state of the manual correction amount Mn during continuous rolling by the apparatus of FIG. As can be seen from FIG. 2, the operational feature of the apparatus of FIG. 1 is that the manual correction amount Mn is zero-cleared by the rate clear amount ΔC1 every time the junction is passed. By performing the zero clear process in this way, the manual correction amount Mn does not reach the limit value Slm even during continuous rolling. In addition, since the manual correction amount Mn is zero-cleared at a predetermined rate, the rolling mill speed does not change suddenly, the influence on the rolling material is small, and the manual correction function can be fully utilized.
[0021]
In the embodiment shown in FIG. 1, the unit correction amount ΔV or −ΔV is read from the storage device 2b or 2c by operating the manual correction operating device 2a to the speed increasing side or the speed reducing side. The unit correction amount of the manual correction operation device 2a and the storage devices 2b and 2c is output in units of several steps according to the operation angle of the manual operation device or continuously changed according to the operation angle. May be output. This modification is also applicable to each embodiment described below.
[0022]
<Embodiment 2>
The second embodiment is an embodiment of the invention according to claim 2. In the second embodiment, as shown in FIG. 3, a signal indicating that a manual correction operation is in progress, that is, a falling of the manual correction operation in-progress signal 2h is used instead of the junction passing signal 2g input to the manual correction clear device 2f in FIG. It is what is used. The manual correction operation in-progress signal 2h can be obtained through a contact that closes when the manual correction operation device 2a is operated in the speed increasing direction or the speed decreasing direction.
[0023]
According to the second embodiment, as in the case of the first embodiment, the manual correction amount calculating device 2e can increase the unit manual correction amount ΔV for acceleration or the unit manual correction amount for deceleration— When ΔV is inputted from the storage device 2b or the storage device 2c, it is integrated, and a manual correction amount Mn for the own stand is obtained and outputted, and the manual speed correction amount Mnx is given to the stand speed correction device 42 via the limiter 3. Perform manual speed correction.
[0024]
On the other hand, the manual correction clearing device 2f inputs the manual correction operation in-progress signal 2h and the manual correction amount Mn, sets ΔC1 = 0 for the time during which the manual correction operation in-progress signal 2h is active, and the manual correction operation in-progress signal 2h is inactive. At the timing of activation, the rate clear amount ΔCl is given to the manual correction amount calculation device 2e, and the manual correction amount Mn is zero-cleared at a rate as in FIG.
[0025]
Thus, even in the embodiment of FIG. 3, the manual correction amount Mn does not reach the limit value Slm during continuous rolling, and the manual correction amount Mn is zero-cleared at a predetermined rate, so that the rolling mill speed changes rapidly. Therefore, the manual correction function during continuous rolling can be fully utilized.
[0026]
<Embodiment 3>
FIG. 4 shows how the manual correction amount Mn changes during continuous rolling according to the third embodiment. As can be seen from FIG. 4, the manual correction amount Mn is zero-cleared by a predetermined rate clear amount ΔC1 from the time when a certain time Td has passed since the time when manual operation is no longer performed. By doing so, the manual correction amount Mn does not reach the limit value Slm even during continuous rolling. In addition, since the manual correction amount Mn is zero-cleared at a rate, the influence on the rolling material is small.
[0027]
<Embodiment 4>
FIG. 5 shows an embodiment according to the third aspect of the present invention. 5 uses the manual correction amount output device 2 that does not include the manual correction clear device 2f shown in FIGS. 1 and 2, and the input method of the zero clear signal to the manual correction amount calculation device 2e is different. This is because a set speed correction device 22 a is interposed between the stand speed setting device 22 and the multiplier 32. The manual correction amount calculation device 2e receives the joint point passing signal 2g, and clears the manual correction amount Mnx to zero in steps by passing the joint point. In addition to the output speed ratio for each material given from the stand speed setting device 22, the set speed correction device 22 a has a manual correction amount Mnx output from the manual correction amount calculation device 2 e via the limiter 3, and a junction passing signal. 2g is input, the speed ratio is corrected with a speed correction amount corresponding to the manual correction amount Mnx that has been output by the manual correction amount calculation device 2e until the time of passing through the junction point, and the manual correction amount Mnx is stepped. A speed ratio that does not change the final speed of the stand even if it becomes zero is obtained and output.
[0028]
Specifically, an arithmetic expression for obtaining the speed ratio at this time will be examined next.
The final speed reference Vrx of the stand uses the output speed reference Vr of the multiplier 32, the manual correction amount Mnx, the automatic correction amount Lpx output from the limiter 5, and the speed correction amount Scx of the downstream stand,
Vrx = Vr (1 + Mnx + Lpx + Scx) (1)
It is represented by Here, it is assumed that there is no direct correlation between the speeds Lpx and Scx related to correction. Immediately before the junction passes, using the master speed Sm and the stand speed ratio Ss2,
Vr = Sm · Ss2 (2)
Therefore, the final speed reference Vrx is
Vrx = Sm · Ss2 (1 + Mnx) (3)
It is represented by
[0029]
According to the present embodiment, even if the manual correction amount Mnx is zero-cleared stepwise by passing through the junction point, in order not to change the final speed by setting the stand speed ratio correction amount Ss2x, The following equation must hold:
[0030]
Sm · Ss2x = Sm · Ss2 (1 + Mnx) (4)
Therefore, Ss2x corrected by passing through the junction is
Ss2x = Ss2 (1 + Mnx) (5)
It is expressed.
[0031]
As is apparent from the above description, according to the present embodiment, even during continuous rolling, the manual correction amount is reset to zero for each material without changing the final speed reference output for driving the electric motor. Even in the case of continuous rolling, the manual correction amount does not exceed the limit value Slm, and the manual correction function during continuous rolling can be fully utilized.
[0032]
<Embodiment 5>
The fifth embodiment is an embodiment of the invention according to claim 4. As shown in FIG. 6, the fifth embodiment uses the manual correction in-operation signal 2h described in FIG. 3 instead of the junction passing signal 2g in the fourth embodiment shown in FIG.
[0033]
In the fifth embodiment, the manual correction is cleared to zero as in the fourth embodiment. However, the timing for correcting the stand speed ratio is that the joint point is passed in the fourth embodiment. This means that a certain time Td has elapsed after stopping.
[0034]
Manual correction is stopped, and the manual correction amount is reset to zero at a certain time, and the speed correction equivalent to the manual correction amount that has been output is corrected to the stand setting speed. By doing so, the manual correction amount can be reset to zero for each material without changing the final speed reference output for driving the motor, so even if multiple pieces of material are joined and rolled continuously, The correction amount does not exceed the limit value, and the manual correction function during continuous rolling can be fully utilized.
[0035]
【The invention's effect】
As apparent from the above description, according to the present invention, the manual speed correction amount is once cleared to zero for each piece of material to be rolled even during continuous rolling, so the speed correction amount is limited during continuous rolling. The value is not applied, and manual speed correction can always be performed during continuous rolling.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of the invention according to claim 1;
FIG. 2 is a diagram showing a pattern of change in manual correction amount in the apparatus of FIG.
FIG. 3 is a block diagram showing an embodiment of the invention according to claim 2;
FIG. 4 is a diagram showing a pattern example of a manual correction amount change in the embodiment of the invention according to claim 2;
FIG. 5 is a block diagram showing an embodiment of the invention according to claim 3;
FIG. 6 is a block diagram showing an embodiment of the invention according to claim 4;
FIG. 7 is a block diagram showing a stand arrangement and a speed control system of a general tandem rolling mill.
8 is a block diagram showing a more detailed speed control system of a specific rolling stand in the apparatus of FIG.
FIG. 9 is a diagram showing a pattern of change in manual correction amount in normal rolling according to the prior art.
FIG. 10 is a diagram showing a pattern of change in manual correction amount in continuous rolling according to the prior art.
[Explanation of symbols]
F1, F2, F3, F4 Rolling stand M1, M2, M3, M4 Electric motor 2 Manual correction amount output device 2a Manual correction operation device 2aa Speed increasing contact 2ad Speed reducing contact 2b Storage device 2c Storage device 2d Adder 2e Manual correction amount Calculation device 2f Manual correction clear device 2g Joint point passing signal 2h Manual correction operation in-progress signal 3 Limiter 4 Automatic correction amount output device 5 Limiter 10 Master speed calculation devices 21, 22, 23, 24 Stand speed setting devices 31, 32, 33, 34 Multiplier 41, 42, 43 Stand speed correction device 22a Set speed correction device 51, 52, 53, 54 Speed control device 61, 62, 63 Speed correction amount calculation device

Claims (4)

In a speed control device of a tandem rolling mill that rolls a rolled material formed by joining a plurality of rolled material pieces vertically long through a rolling stand having a tandem arrangement,
A first means for automatically setting a speed reference for each rolling stand;
A second means for adding a positive or negative correction amount that increases with the passage of time to the speed reference by a manual operation while a material to be rolled is caught in a rolling mill for a rolling stand other than the final rolling stand. When,
A speed control device for a tandem rolling mill, comprising: a third means for zero-clearing the correction amount at a predetermined rate at a timing when a joining point of the rolled material pieces passes through a rolling stand to be corrected. In a speed control device of a tandem rolling mill that rolls a rolled material formed by joining a plurality of rolled material pieces vertically long through a rolling stand having a tandem arrangement,
A first means for automatically setting a speed reference for each rolling stand;
A second means for adding a positive or negative correction amount that increases with the passage of time to the speed reference by a manual operation while a material to be rolled is caught in a rolling mill for a rolling stand other than the final rolling stand. When,
Tandem rolling comprising: third means for zero-clearing the correction amount at a predetermined rate at a timing when a predetermined time has elapsed from the time when the manual operation for correcting the speed reference is stopped Machine speed control device. In a speed control device of a tandem rolling mill that rolls a rolled material formed by joining a plurality of rolled material pieces vertically long through a rolling stand having a tandem arrangement,
A first means for automatically setting a speed reference for each rolling stand;
A second means for adding a positive or negative correction amount that increases with the passage of time to the speed reference by a manual operation while a material to be rolled is caught in a rolling mill for a rolling stand other than the final rolling stand. When,
A third means for zero-clearing the correction amount stepwise at the timing when the joining point of the rolled material pieces passes through the rolling stand to be corrected;
A tandem rolling mill comprising: a fourth means for adding a speed change corresponding to the correction amount output by the second means until immediately before the joining point passes to the speed reference. Speed control device. In a speed control device of a tandem rolling mill that rolls a rolled material formed by joining a plurality of rolled material pieces vertically long through a rolling stand having a tandem arrangement,
A first means for automatically setting a speed reference for each rolling stand;
A second means for adding a positive or negative correction amount that increases with the passage of time to the speed reference by a manual operation while a material to be rolled is caught in a rolling mill for a rolling stand other than the final rolling stand. When,
A third means for zero-clearing the correction amount in a stepwise manner at a timing when a predetermined time has elapsed from the time when the manual operation for correcting the speed reference is stopped;
A tandem rolling mill comprising: a fourth means for adding, to the speed reference, a speed change corresponding to the correction amount that the second means outputs until immediately before the correction amount is cleared to zero. Speed control device.

Images