JPS6010808B2 - Shape control device for reversible rolling mill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shape control device for a reversible rolling mill, and more particularly to a shape control device for improving the planar shape of a rolled material using a reversible rolling mill and a rolling device.

The method of improving the planar shape of a rolled material using a reversible rolling mill (hereinafter referred to as a mill) and a rolling device is performed through complex control such as hydraulic rolling and process controller control.

In particular, in the rolling method for improving the planar shape, the mill requires a lower rolling speed than the normal rolling speed, and a stepwise rotational speed on the order of 1 rpm.

In addition, in the rolling speed control device (ASR) of a mill motor, droop (Droop) is used to provide drooping characteristics (DrMp) due to ball vibration and control system protection, rolling technology, etc.
) is equipped with a circuit. In reversible rolling mills, 1 to 5% is added to the drooping characteristics to protect the electrical and mechanical properties of the motor, etc.
The formula is as follows. Dr's p (%) = Tshako Mai m B is the rotation speed of the mill motor, C is the movement of the rolled material (metal), and at C, C,,C3
is metal out and C2 is metal in.

While the rolled material is being bitten by the mill in this way, as shown in B, the designated speed Qrpm cannot be maintained and it drops by Δrpm. This △rpm is △■m=third grade ≧XT■rpm

Here, Δrpm is the decreasing rotational speed at a certain load, and Toprmp is the rated maximum rotational speed of the mill motor. This △rpm is the load current (=load torque) and D
It changes depending on rｽp(%). DrMp (%) is currently constant at a certain value and cannot be changed arbitrarily during operation.In addition, the speed changes depending on the torque (crab flow).Therefore, the plate thickness changes in the cross section of the rolled material in the rolling direction. After this, the material to be rolled is rolled with 900 rotations to perform planar shape (control) rolling to improve the planar shape (to make it rectangular) of the rolled material after rolling. Control) When performing rolling, there is a drawback that the effect deteriorates due to changes in mill speed.The purpose of the present invention is to develop a reversible rolling mill that can improve the shape of all rolled materials in reduction control and ultra-low distance rolling. The purpose of the present invention is to provide a shape control device.

The present invention is a rolling control that improves the planar shape of a rolled material using a reversible rolling mill and a rolling device. The ultra-low distance setting is performed step by step in the far speed control circuit, and furthermore, the droop characteristic control circuit in the rolling speed control circuit sets a constant droop characteristic based on the predicted torque and rotational speed command according to the rolled material. In addition, on the side of the rolling device, commands for lowering, stopping, and raising the rolling device are outputted from the rolling control circuit to a rolling speed control circuit that drives the rolling motor of the rolling device.

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

FIG. 2 shows the configuration of a reversible rolling mill to which the shape control device for a reversible rolling mill of the present invention is applied.

In the figure, a mill 1 is rotated by a mill motor 2, and by this rotation, a rolled material carried in from a table 3 is rolled and then sent to a table 4. The mill 1 is provided with a rolling down device 5, and the rolling down device 5 is driven by the rotation of the rolling down motor 6, thereby giving the mill 1 a rolling motion. The rolling operation of the rolling down device 5 is detected by a load cell 7 attached to the rolling down device 5. FIG. 3 shows an embodiment of the shape control device for a reversing rolling mill of the present invention applied to the reversing rolling mill.

In the figure, the drive of the mill motor 2 is controlled by a speed control device 10. Rolling speed control device 1 is composed of a speed controller 11, a current controller 12, a voltage controller 13, a thyristor gate control circuit 14, and a thyristor control circuit 15. A reference voltage is input to this rolling speed control device 1 from a reference voltage control unit 20. The reference voltage control unit 20 has a normal/switch command 21 as an operating condition signal contact 2.
2 and extremely low speed setting circuit 3.
A very low speed setting signal from 0 is inputted via the operating condition signal contact 23. The rear point 22 is a normally open contact, and the contact 23 is a normally open contact. The operating condition signal contacts 22 and 23 are contacts that turn on or off depending on the establishment of the operating condition signal 24, and the operating condition signal 24 here is a tentative name for an operating condition signal for performing shape control.

That is, the components of the operating condition signal 24 include, for example:
A mode selection signal for rolling only a few passes on one rolled material, a rolling setting completion signal in the rolling device, a signal established by normal and turned-on condition signals in each electrical equipment, and other various conditions. There is. The ultra-low distance speed setting circuit 30 is provided to set the speed of the mill motor 2.

That is, in the extremely low distance speed setting circuit 30, the extremely low distance speed setting device 31 is provided to create a rotation speed command as a rear point signal using a push button (PB) or a program controller. A stepwise rotational speed command is generated based on a combination of 5-point commands of 2, 4, 8, 1 & Pm.
The output of this extremely low distance setting device 31 is input to a D/A (digital analog) converter 32.
consists of a variable resistor. A constant voltage output from a DC constant voltage control amplifier 33 is input to this D/A converter 32 . A positive voltage is input to the input terminal of the amplifier 33 via the mill motor forward rotation command contact 34F, and a negative voltage is input via the mill motor reverse rotation command contact 34R. Therefore, a voltage whose polarity differs depending on the direction of rotation is inputted from the amplifier 33 to the ○/A converter 32, and from the D/A converter 32, the voltage is outputted according to the rotational speed (rpm) specified by the ultra-low speed setting device 31. A reference voltage is input to the polarity inversion amplifier 35. The reference voltage whose polarity is inverted and amplified by the polarity inverted amplification amplifier 35 is applied to the reference voltage control unit 20 via the variable resistor 36. The above is the speed control device 10 and the extremely low distance speed setting circuit 30.
However, a drooping characteristic control circuit 40 is added to the rolling speed control device 10.

The drooping characteristic control circuit 40 includes a logic converter 41 and a D/A
It is composed of a convertible variable resistance unit 42. That is, the predicted torque signal 43, rotational speed command signal 44, and operating condition signal 24 are input to the logic converter 41, and the logic converter 41 converts the Droop according to the rolled material from each signal.
The quantity is logically converted and given to the D/A conversion type variable resistance unit 42 as a contact signal. In the D/A conversion type variable resistance unit 42, a resistance selection corresponding to the input signal is made and inputted to the speed controller 11 as a "Droop width setting." To specifically explain the setting of the Droop amount,
The input voltage corresponding to the designated rotational speed from the reference voltage control unit 20 of the speed controller 11 is V, the input voltage for the output voltage is V2, the output voltage of the speed controller amplifier 11 is V3, and 0/A conversion is performed. The rated resistance of the variable resistance unit 42 is R, and this . If the setting resistance is R2, the input voltage V2 for Droop is V2=V3×R2/R
．． ...'3', and the current controller 12 is V
Since the current can be controlled to 2.25% of the rated current at the input of DrO.

P (%) is Droop (%) = Mamoru x Hirokari.

By varying the setting resistor R2, the input voltage V2 changes, and as a result, the Dr plate p (%) changes.

Therefore, if the circuit of this embodiment is used, the resistance value can be changed by the D/A conversion type variable resistance unit 42 in order to keep Δrpm constant according to the rotational speed command and torque, and the D/A conversion type variable resistance unit 42 can change the resistance value.
rMp (%) can be variably controlled, therefore, △
The rpm can be kept constant. Specifically, the drooping characteristic control circuit 40' is composed of a circuit as shown in FIG.

That is, the logic converter 41 is a band circuit 41 1, 41
It consists of a plurality of AND circuits such as 2, 413, etc., and each AND circuit 411, 412, 413 receives a predicted torque signal 43, a rotational speed command signal 44, and an operating condition signal 45 from a processor (not shown). D/A
The variable resistance unit 42 is the speed controller 11
A plurality of contacts 421, 422 connected between the input and output terminals of
, 423 and variable resistors 461, 462, 463, . That is, by the droop characteristic control circuit 40, the Droop curve is controlled by the predicted torque signal 43 from the block controller.
Variable resistances 461, 462, 4 for drooping characteristics are determined by each combination of rotational speed command signal 44 and operating condition signal 45.
63... is selected and determined. Next, the reduction device 5
To explain the control, the rolling down motor 6 is driven and controlled by a rolling down speed control device 50.

This speed control device 5 has the same configuration as the speed control device 10 described above. This rolling speed control bag counterfeit 501 is connected to a rolling control circuit 60 in order to input a rolling control command to the rolling speed control device 50. This reduction control circuit 60
includes the load cell 7, from which a metal-in signal 7A and a metal-out signal 7B are output. One of the metal-in signals 7A is input to an AND circuit 61, and the AND circuit 61 generates a pulse output together with the metal-in signal 7A by the establishment of a pulse 62A from a pulse oscillator 62 connected to the mill motor 2.
This pulse output 61A is input to the counter 63. The counter 63 is composed of two setting counters, setting 1 corresponds to the end point of the downward movement of the rolling device 5, and setting 2 corresponds to the starting point of the upward movement of the rolling device 5.Each setting corresponds to the rolling material when the shape rolling mode is selected. It is set accordingly. This counter 63 generates output signals 63A, 63B,
Moreover, it is reset by the metal-out signal 7B from the load cell 7. Output signal 63A is output until setting 1 steps up, and output signal 63A is output until setting 1 steps up.
3B is a signal that is output until setting 2 steps up. The AND circuit 64 is the lowering device 5
The output signal 63A, the metallization signal 7A from the load cell 7, and the operating condition signal 24 are input to this AND circuit 64.

A descending command 69A is output when all of these signals are established. Further, an AND circuit 66 is provided to output an ascending command signal for the lowering device 5, and this AND circuit 66 receives the output signal 63B of the counter 63, the metal out signal 78 from the load cell 7, and the operating condition signal 24. It has been entered.

The ascending command 69B is output when all of these signals are established. An OR circuit 67 is connected to the AND circuit 64.
Further, an OR circuit 68 is connected to the AND circuit 66 . The OR circuit 67 outputs a descending command signal 69A based on the manual descending command 67A or the output 64A of the AND circuit 64, while the OR circuit 68 outputs a rising command signal 69B based on the hand sardine command 68A or the output 66A of the AND circuit 66. It is now output. The shape control operation will be explained based on the above configuration.

In the case of normal rolling, the mill motor 2 is normally operated by turning off the operating condition signal contact 23 by the /c command 21, and applying the reference voltage (Ref) to the speed control device 1 via the reference voltage control unit 20. It is done by

Next, in the case of shape control rolling mode selection, the operating condition signal contact 22 is turned off and the operating condition signal contact 23 is turned on, so that the reference voltage control unit 20 is disconnected from the normal notch command 22.

In this case, the speed of the mill motor 2 is set by the output of the extremely low speed setting circuit 30. The DC constant voltage control amplifier 33 has a forward rotation command saddle point 34.
Positive voltage is input through F, and reverse command contact 34R
A negative voltage is inputted through the D/A converter 32, and the output voltage whose polarity differs depending on the direction of rotation is inputted to the variable resistor that constitutes the D/A converter 32.

This D/A converter 32 outputs a reference voltage corresponding to the specified rotational speed (rpm) based on the combination of 5-point commands of 1, 2, 4, 8, and 16 rpm from the extremely low speed setting device 31. This reference voltage is output, and after being polarized and amplified by an amplifier 35, it is inputted to a reference voltage control unit 201 via a variable resistor 36. Based on the output of the control unit 20, a control drive output is input from the speed control circuit 10 to the mill motor 2, and the mill motor 2 is rotated.
In the drooping characteristic control circuit 4, the logic converter 41
The predicted torque signal 43, the rotational speed command signal 44, and the operating condition signal 24 are input to the logic converter 41, and a Dr skin p amount output corresponding to the rolled material is generated as a logic conversion output. It is input to unit 42. In this resistance unit 42, a resistance selection corresponding to the input signal is made and inputted to the speed controller 11 of the speed control circuit 10 as the Dr skin p setting. next,
The control pattern of the rolling device 5 will be explained based on FIG.
4 is input to the AND circuit 66 together with the logic converter 41.

The counter 63 is set to 1 (
(descent end point) and setting 2 (ascent start point) are set in advance according to the rolled material.

B indicates a metal-in signal 7A and a metal-out signal 7B, where the metal-in signal 7A is output from the load cell 7 when the rolled material is bitten by the mill 1', and the metal-out signal 7B indicates that the rolled material has come off the mill 1'. This is the signal for the case.

C indicates the lowering and rising of the lowering device 5, C, is lowering, C2
is an increase.

That is, the lowering of the lowering device 5 is performed at the same time as the count step of the counter 63 as shown in FIG. Up (step
up), the counter 63 is reset.
The details of this downward and upward movement are as follows.The input pulse 61A of the counter 63 is output from the AND circuit 61, and the output pulse 61A of the AND circuit 61 is combined with the generated pulse 62A of the pulse generator 62 and the load cell 7. It is generated when the metalin signal 7A is established.

The counter 63 counts this. Descending command signal 69A output from AND circuit 64 via OR circuit 67
is output based on the metalin signal 7A, the conditions before the explanation 1 of the counter 63 does not step up, and the establishment of the operating condition signal 24. This output descending command signal 6
9A is input to the speed control device 5, and as a result, the rolling down motor 6 is driven and the rolling down device 7 starts to descend. Then, the setting 1 of the counter 63 steps up (ste
pup), the AND condition of the AND circuit 64 is not satisfied, and the lowering motor 6 is stopped. Next, when the setting 2 of the counter 63 steps up, the AND condition of this signal 63B, the operating condition signal 24, and the non-metal-out condition signal is established, and an increase command signal is sent from the AND circuit 66 via the OR circuit 68. 698
is input to the rolling speed control device 50.

As a result, the rolling down motor 6 is rotated and the rolling down device 7 is raised, and this raising is stopped when the AND condition of the AND circuit 66 is not satisfied by the metal out signal 7B. Note that the counter 63 is reset for both settings 1 and 2 using the metal out signal 7B.

The mill motor 2 normally follows the notch command when the metal is out due to the completion of rolling.

As explained above, since the extremely low far speed setting circuit 31 makes it possible to generate the reference voltage output corresponding to the rotational speed in units of lrpm, when flat shape rolling is performed, the minimum motor speed setting for the secondary mill is Below the notch and lrp
It can meet speed requirements in m units.

This is a significant improvement in this embodiment, whereas in the conventional circuit, the reference voltage at the maximum notch is about 20% of the maximum notch. In addition, in the droop characteristic control circuit 4, after logic conversion based on the predicted torque and rotational speed command according to the rolled material, the Droop
By changing the variable resistance unit 42 for constant drooping characteristics during extremely low distance rolling, a predetermined downward slope and upward slope can be obtained for the rolling direction cross section of the material to be rolled at the set rolling speed and rolling speed. After imparting the target plate thickness cross-sectional change, the material to be rolled is turned and rolled by nine pins, thereby achieving the effect of forming the target rectangular planar shape.

In other words, variation in load during metallization (high load → light load)
If this happens, the Δrpm decreases by Δrpm compared to when the load is high, causing speed fluctuations, and as shown by the broken line in FIG. 5, the predetermined descending and ascending points cannot be obtained.

For this reason, the reduction by the rolling device varies with respect to the rolling mill, making it impossible to sufficiently control the shape and making it impossible to improve the planar shape. Moreover, since the Shoshita control is a control that inputs the pulses of the pulse oscillator 62 to the counter 63,
If the mill motor speed fluctuates, no improvements in planar shape will be made. Therefore, in this embodiment, by keeping △rpm constant even when the load fluctuates, the desired reduction pattern (timing control of lowering and raising) shown in FIG. 5 is obtained. .

For example, when the speed command during extremely low speed rolling is 1 ratio pm, Dr.
oop3%, Top rpmlo pm, load current 100
Assuming %, △ target m = 3rd grade fist XT.

p■mX member Mitdenrei=Zhi.

xloo summary = 3pm However, the rated current shall be 100%.

From the above formula, the rolling speed at this time is 1 ratio pm - 3 pm = 7
rpm.

Under the above conditions, when only the load current becomes 200%, △rpm
It becomes a rough pm.

And the rolling speed is 1pm-&Pm=4rpm,
The speed changes even with the same speed command. Therefore, as a method of keeping Δrpm constant, the load torque is predicted and inputted to the logic.

In the above case, the load is predicted to be 200%, so it is difficult to try to keep 3pm (△rpm) constant.
This becomes possible by setting loop to 1.5%.

As a result, in this embodiment, as shown in FIG. 5, the rising and falling points of the rolling reduction do not deviate as shown by the broken lines, and shape control can be performed according to a predetermined pattern, thereby improving the planar shape. Furthermore, the lowering control circuit 6 performs control using a counter 63, and in combination with the load cell 7, the lowering end point and rising start point of the lowering device 5 can be arbitrarily set, making it possible to set a relatively simple The configuration makes it possible to improve the planar shape.

Incidentally, the raising and lowering operations of the rolling down device 5 are performed at the maximum speed of the rolling down motor 6, and the effect thereof has been verified through experiments.

As explained above, according to the present invention, the target planar shape can be improved in accordance with any rolled material, and the shape effect can be increased with a simple configuration.

[Brief explanation of drawings]

FIG. 1 is a time chart showing drooping characteristics, FIG. 2 is a configuration explanatory diagram of a rolling machine to which the present invention is applied, and FIG. 3 is a block diagram showing an embodiment of a shape control device for a reversible rolling machine of the present invention. FIG. 4 is a circuit diagram showing a specific configuration of the drooping characteristic control circuit, and FIG. 5 is a time chart showing the operation pattern of the drooping control circuit. 1... Mill, 2... Motor for mill, 5...
・・Down device, 6...・Down motor, 10, 50...
... Speed control circuit, 30 ... Very low distance speed setting circuit, 40 ... Drooping characteristic control circuit, 60 ...
...pressure control circuit, 62...''pulse oscillator. Fig. 1 Fig. 2 Fig. 5 Fig. 3 Fig. 4

Claims (1)

[Claims] 1. A rolling speed control circuit that drives a rolling mill motor, and is connected to this rolling speed control circuit via an operating condition signal contact that is switched during shape control rolling, and sets extremely low rolling speed in stages during shape control rolling. an extremely low speed setting circuit; a drooping characteristic control circuit that is added to the speed control circuit and keeps the drooping characteristics constant based on the predicted torque and rotational speed according to the rolled material; and a rolling speed control circuit that drives the rolling motor of the rolling device. and a pulse oscillator that generates pulses in response to the rotation of the rolling mill motor, which is connected to the rolling speed control circuit and into which the output pulses of the pulse oscillator are input, and the number of pulse counts can be set arbitrarily. 1st and 2nd
When the rolling of the rolled material starts, a descending command signal is output for the rolling device, and when the pulse count reaches the first set value, the output of the descending command signal is stopped, and the second set value is set. 1. A shape control device for a reversible rolling mill, comprising a rolling control circuit that outputs a raising command signal for a rolling device when a pulse count reaches , and controlling the shape according to the material to be rolled.