JP5501838B2 - Rolling control method and rolling control apparatus - Google Patents

Description

  The present invention relates to a rolling control technique, and more particularly to a control technique in a case where a material to be rolled having a non-uniform radius is wound or wound.

  In a rolling mill, a plate-shaped material to be rolled is wound into a cylindrical coil for storage or transportation. When rolling the rolled material in a coil shape with a rolling mill, the rolled material is unwound and rolled with a rolling mill to reduce the plate thickness, and the rolled material is wound again and wound into a coil shape. To do. As a device for this, a mechanical device called a tension reel is usually used.

  When the material to be rolled is wound in a coil shape, the material to be rolled is wound around a cylindrical mechanical device (reel main body) of a tension reel, but the material to be rolled is placed on the tip of the material to be rolled. Therefore, when the material to be rolled is wound in a coil shape, a step corresponding to the plate thickness occurs at the tip. When the tension reel cylindrical machine (reel body) has a radius of about 300 mm and the plate pressure of the material to be rolled is about 3 mm, the coil radius varies by 1%.

  In addition, as a method of winding the material to be rolled around the tension reel body, a method is used in which a groove is cut in the plate width direction in the cylindrical portion and the tip of the material to be rolled is inserted and wound there. In that case, although it depends on the shape of the groove in the plate width direction, a radius variation occurs in the rolled material coil.

  Since rolling or unwinding of the material to be rolled is performed by rotating the cylindrical portion of the tension reel, if the radial dimension of the coil changes, the winding and unwinding speed of the material to be rolled will change by the amount of radial fluctuation. become.

  In the rolling mill, a law called “mass flow rule” is established: “Roller entry-side rolled material speed × Roller entry-side sheet thickness = Roller delivery-side rolled material speed × Roller exit-side sheet thickness”. According to this, even if the entry side plate thickness is constant, if the entry side rolled material speed fluctuates due to reel radius fluctuation, the rolling mill outlet side plate thickness also fluctuates, and the product accuracy of the rolled material deteriorates.

  For this reason, conventionally, reel eccentricity control has been performed to suppress coil radius fluctuations (referred to as reel eccentricity because of fluctuations in the radial dimensions of the tension reel). As a method for controlling the eccentricity of the reel, the speed fluctuation caused by the fluctuation in the radius of the reel is predicted from the fluctuation in the thickness of the exit side of the rolling mill or the tension fluctuation on the exit side of the rolling mill. A method of suppressing the thickness variation or a method of suppressing the tension variation and the exit side plate thickness variation by changing the speed of the material to be rolled by operating the electric current of the electric motor that drives the tension reel (Patent Documents 1 and 2). .

  In the method of changing the roll gap of the rolling mill, there is a problem that the tension fluctuation increases, and the effect of suppressing the outlet side plate thickness is also small due to the tension fluctuation. Further, the method of changing the electric current of the electric motor that drives the tension reel is limited to localization of the reel radius variation (about 10 to 30 degrees in angle). There was a problem that the fluctuation could not be suppressed and it was not practical.

Japanese Patent Laid-Open No. 10-277618 JP 2000-84615 A

  As described above, there are a method of operating the roll gap and a method of operating the electric current of the electric motor that drives the tension reel as a control method for removing the plate pressure fluctuation due to the reel eccentricity of the rolling mill.

  In the method of changing the roll gap of the rolling mill, the tension fluctuation increases as a rolling phenomenon, so that there is a problem in operation stability. In addition, there is a problem that the effect of suppressing the outlet side plate thickness is small due to tension fluctuation.

  Further, the method of changing the electric current of the electric motor that drives the tension reel is limited to localization of the reel radius variation (about 10 to 30 degrees in angle). There is a problem that the fluctuation cannot be suppressed and it is not practical.

  The plate speed fluctuation of the material to be rolled due to the eccentricity of the reel needs to be suppressed by changing the reel rotation speed, but the tension reel has a large moment of inertia, and it takes time from the drive current change of the motor to the reel speed fluctuation. Since there is a delay, it is difficult to suppress plate speed fluctuation. Moreover, the plate | board speed fluctuation | variation of the generate | occur | produced material to be rolled turns into a board | substrate thickness fluctuation | variation from a mass flow fixed law, and it is difficult to suppress this.

  The present invention has been made in view of these problems, and a rolling control technique capable of effectively absorbing the plate speed fluctuation of the material to be rolled due to the reel eccentricity and minimizing the influence on the outlet side plate thickness. It is to provide.

  In order to solve the above problems, the present invention employs the following means.

  In a control device of a rolling mill comprising a rolling mill and a tension reel that winds or unwinds the material to be rolled on at least one of the entrance side and the exit side of the rolling mill, the material to be rolled between the rolling mill and the tension reel Equipped with a reel eccentricity removal roll that applies pressing force, and adjusts the pressing force applied to the reel eccentricity removal roll based on the deviation from the reference position of the reel eccentricity removal roll and the tension setting value set on the tension reel And the fluctuation | variation of the tension | tensile_strength to the said to-be-rolled material accompanying the fluctuation | variation of the unwinding of the said to-be-rolled material or winding speed which generate | occur | produces with eccentricity of the to-be-rolled material wound by the said tension reel is suppressed.

  Since the present invention has the above-described configuration, it is possible to effectively absorb the plate speed fluctuation of the material to be rolled due to the eccentricity of the reel and minimize the influence on the outlet side plate thickness.

It is a figure explaining a reel eccentricity suppression control apparatus. It is a figure explaining the single stand rolling mill which is the application object of this invention. It is a figure explaining the method of winding a to-be-rolled material around a tension reel. It is a figure explaining the to-be-rolled material speed fluctuation | variation by reel eccentricity. It is a figure explaining the fluctuation | variation of the to-be-rolled material length between a tension reel and a rolling mill. It is a figure explaining tension variation control operation by reel eccentricity. It is a figure which shows the detail of a reel eccentricity removal control apparatus. It is a figure explaining the detail of a pressing pressure adjustment apparatus. It is a figure which shows the example which has arrange | positioned the roll eccentric removal apparatus between the rolling stands in a tandem rolling mill.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a diagram illustrating a single stand rolling mill to which the present invention is applied.

  The single stand rolling mill includes an entry side TR (a tension reel is abbreviated as TR) 2 on the entry side and an exit side TR3 on the exit side with respect to the rolling direction of the rolling mill 1. In rolling, the material to be rolled that has been unwound from the entry side TR2 is rolled by the rolling mill 1 and then taken up by the exit side TR3. The rolling mill 1 is provided with a roll gap control device 7 for controlling the sheet thickness of the material to be rolled by changing the roll gap and a mill speed control device 4 for controlling the speed of the rolling mill 1.

  The entry-side TR2 and the exit-side TR3 are driven by an electric motor, and an input-side TR control device 5 and an output-side TR control device 6 are installed as devices for driving the electric motor and the electric motor.

  During rolling, a speed command from the rolling speed setting device 10 is output to the mill speed control device 4, and the mill speed control device 4 performs control to keep the speed of the rolling mill 1 constant.

  On the entry side and the exit side of the rolling mill 1, rolling is performed stably and efficiently by applying tension to the material to be rolled. It is the entry side tension setting device 11 and the exit side tension setting device 12 that calculate the necessary tension.

  The input side tension setting unit 11 calculated by the input side tension setting device 11 and the output of the input side tension control unit 13 receiving the difference between the input side tension setting value and the measured value of the input side tension meter 8 are input side It is given to the entry side TR control device 5 via the tension current conversion device 15, and the entry side TR control device 5 controls the motor current to give the given current, and gives a predetermined tension to the material to be rolled.

  Further, the output of the output side tension control unit 14 that receives the output side tension setting value calculated by the output side tension setting device 12 and the difference between the output side tension setting value and the measured value of the output side tension meter 9 is as follows: It is given to the outgoing side TR control device 6 via the outgoing side tension current converter 16, and the outgoing side TR control device 6 controls the electric motor current to give the given current and gives a predetermined tension to the material to be rolled.

  The tension current converters 15 and 16 calculate a current set value (motor torque set value) such that the tension set value can be obtained based on a control model representing a TR control device including a TR mechanical system. Since the control model includes an error, the input side tension control is performed using the actual tension measured by the inlet side tension meter 8 and the outlet side tension meter 9 installed on the inlet side and the outlet side of the rolling mill 1. 13 and the output side tension control 14, the tension set value is corrected and applied to the tension current converters 15 and 16 to correct the current values set in the input side TR control device 5 and the output side TR control device 6.

In addition, since the plate | board thickness of a material to be rolled is important on product quality, plate | board thickness control is implemented. In the sheet thickness control, the sheet thickness on the exit side of the rolling mill 1 is detected by the sheet thickness meter 17 on the exit side, and the exit side thickness control device 18 is based on the detected sheet thickness via the roll gap control device 7. As described above, in the single stand rolling mill, the tension control by TR used for winding and unwinding is performed by constant torque control that makes the torque generated by the electric motor constant. . That is, control is performed to make the tension applied to the material to be rolled constant by correcting the motor current command using the actual tension detected by the tension meter. Since the motor torque is obtained from the motor current, the constant current control may be used instead of the constant torque control.

  FIG. 3 is a diagram illustrating a method of winding a material to be rolled around TR. There are two methods as shown in FIGS. 3 (a) and 3 (b).

  Fig.3 (a) is a figure which shows the example which winds a to-be-rolled material as it is to the cylindrical part of TR. In this case, the material to be rolled increases by one sheet between point A and point B. For this reason, this portion is a portion where the reel radius changes. FIG. 3B is a diagram showing an example in which the tip biting groove of the material to be rolled is mechanically installed in the TR width direction. In this case, as shown in the figure, after putting the tip of the material to be rolled into the groove for biting the tip, the reel is rotated to wind up the material to be rolled. For this reason, the reel radius changes between point C and point D.

  3A and 3B, the reel radius changes regardless of which winding method is used. Therefore, when the reel is rotated at a constant rotation speed, the speed of the material to be rolled varies.

  Further, it can be seen that, regardless of the winding method, the amount of change in the reel radius changes depending on the thickness of the material to be rolled and the state of the tip. Accordingly, it is difficult to control the reel eccentricity by geometrically obtaining the reel radius variation and changing the reel rotation speed.

  FIG. 4 is a diagram for explaining the material speed fluctuation due to the reel eccentricity. Here, as an ideal state, as shown in FIG. 4, it is assumed that the reel radius changes in the range of the reel angle β and the reel peripheral speed (circumferential speed) changes in a triangular shape.

  FIG. 5 is a diagram for explaining the variation in the length of the material to be rolled between the tension reel and the rolling mill. Considering the rolling mill entry side, as shown in FIG. 5, the length of the sheet from the reel to the rolling mill (the length of the material to be rolled from point E to point F) changes as shown in FIG. 5 (c). To do.

  When the plate length between the tension reel and the rolling mill changes, the tension between the tension reel and the rolling mill changes. When the tension fluctuates, the entry side TR that performs the constant torque control changes the speed accordingly to suppress the tension fluctuation and return the reel-to-roller plate length to the original length. For this reason, the reel speed also fluctuates, and the strip thickness on the delivery side of the rolling mill fluctuates according to the constant mass flow rule.

  FIG. 6 is a diagram for explaining a tension fluctuation suppressing operation due to reel eccentricity. As shown in FIG. 6A, a reel eccentricity removing roll 21 for applying a pressing force by a hydraulic cylinder 22 is installed on a material to be rolled between the entry side reel and the rolling mill.

  The pressing force set for the hydraulic cylinder 22 is changed according to the entry side tension setting. When the reel radius does not change, the cylinder position is a fixed position. When the reel radius changes due to the eccentricity of the reel, the length between the reel and the rolling mill changes, and appears as entry side tension fluctuation. Since the reel eccentricity removing roll 21 is pressed against the material to be rolled at a constant pressure, when the entry side tension varies, the position changes accordingly. When the reel diameter changes due to the eccentricity of the reel, the entry side tension is loosened. Therefore, the reel eccentricity removing roll 21 moves in the direction of pushing the material to be rolled, and the length between the reel and the rolling mill is increased. Thus, fluctuations in the entrance side tension of the rolling mill are suppressed, and fluctuations in the exit side plate thickness are also suppressed.

  When the reel rotates to a portion where there is no change in the reel radius, the pressing pressure of the reel eccentricity removing roll 21 is changed, and the position is moved in the direction of decreasing the entry side tension. At this time, the input side tension fluctuation is suppressed by the torque-constant control of the input side TR. Further, the pressing pressure is changed so that the position of the reel eccentricity removal roll 21 is changed at a rate at which the entry side TR can be controlled or the exit side plate thickness variation is allowed.

  That is, as shown in FIG. 6 (d), in the vicinity of the grip mark position where the reel radius fluctuation is large due to the reel eccentricity, the reel eccentricity removal roll position is greatly operated to change the inlet side tension fluctuation and the outlet side plate thickness fluctuation. Suppressing, and then gradually returning the changed position to the original position, thereby generating a reel speed change by constant torque control of the entry side TR, thereby suppressing entry side tension and exit side plate thickness fluctuations.

  FIG. 1 is a diagram illustrating a reel eccentricity suppression control device. As shown in FIG. 1, a reel eccentric removal roll 21 and a hydraulic cylinder 22 for adjusting the pressing pressure thereof are provided between the rolling mill 1 and the entry side TR2. A pressure adjusting valve 24 for adjusting the hydraulic pressure supplied from the hydraulic source 23 and the hydraulic source to the hydraulic cylinder 22 is also provided. In addition, as the sensor, an entry side tension meter 25 is provided, and a tension result 36 is taken in. The rolling schedule setting device 35 outputs the tension setting 34 on the rolling mill entry side based on the product information of the material to be rolled.

  The reel eccentricity control device 31 uses the actual track position 37 of the reel eccentricity removal roll 21 based on the given tension setting 34, and tension setting-1 for the entry side TR control device 5 and tension setting-2 for the pressing pressure adjustment device 30. Set.

  FIG. 7 is a diagram showing details of the reel eccentricity removal control device 31. As shown in FIG. 7, the tension set value 34 is output as it is as the first tension set value 32 for the ingress TR control device 2.

  Also, the sum of the tension set value 34 and the value obtained by integrating the conversion gain G (converting the position into tension) with respect to the value obtained by limiting and limiting the deviation between the actual position 37 of the reel eccentricity removal roll and the reference position by the limiter. Is the second tension setting 33.

  FIG. 8 is a diagram illustrating details of the pressing pressure adjusting device 30. As shown in FIG. 8, the value obtained by multiplying the deviation between the second tension setting value from the reel eccentricity removal control device 31 and the actual tension value 36 by an integral gain and the sum of the second tension setting value 33 is converted. A gain command (converting tension into pressure) is integrated to create a pressure command for the pressure regulating valve 24. The ingress TR control device 5 receives a current command obtained by converting the first tension set value from the reel eccentricity removal control device 31 into a current command by the tension-current conversion device 15, and performs constant current control.

  In addition, since the position of the reel eccentricity removing roll 21 changes according to the actual tension of the material to be rolled, it is strictly necessary to correct the pressure command according to the actual position. However, since the reel diameter changes according to the rolling state (the reel diameter changes every reel rotation since the material to be rolled is taken up and unwound), it is difficult to correct geometrically. For this reason, in the present invention, correction is performed by performing integral control using the actual tension so that the actual tension matches the set tension.

  In the above example, the method of removing the influence of the reel eccentricity of the tension reel on the entry side of the rolling mill on the entry side tension and the thickness of the exit side plate has been described. The influence on the tension and the outlet side plate thickness can be removed by the same method.

  In the above example, the method of removing the influence of the eccentricity of the reels on the entrance and exit sides of the single stand rolling mill has been described. Similarly, tension reels are installed on the entrance and exit sides of the tandem mill. It can be applied even if

  FIG. 9 is a diagram showing an example in which a roll eccentricity removing device is arranged between rolling stands in a tandem rolling mill. As shown in FIG. 9, a roll eccentric removal roll 21 'and a hydraulic cylinder 22' for adjusting the pressing pressure thereof are provided between the #i rolling stand and the # i + 1 rolling stand. Further, as the sensor, an input side tension meter 25 'is provided, and a tension result 36' is captured. The roll eccentricity control device 31 ′ uses the actual track position 37 of the reel eccentricity removal roll 21 based on the given tension setting, and tension setting-1 for the #i rolling stand and tension setting for the pressing pressure adjustment device 30 ′. -2 is set.

  Thus, by providing the same configuration as the reel eccentricity removing device between the rolling stands of the tandem rolling mill, the influence of the roll eccentricity of the rolling stand in the tandem rolling mill can be removed.

1 Rolling machine 2 Entry side TR (tension reel)
3 Outgoing TR (Tension Reel)
4 Mill Speed Control Device 5 Input Side TR Control Device 6 Output Side TR Control Device 7 Roll Gap Control Device 8 Input Tension Meter 9 Output Side Tensiometer 10 Rolling Speed Setting Device 11 Input Side Tension Setting Device 12 Output Side Tension Setting Device 13 Input Side tension control unit 14 Delivery side tension control unit 15 Delivery side tension-current conversion device 16 Delivery side tension-current conversion device 17 Delivery side pressure gauge 18 Delivery side plate thickness control device
DESCRIPTION OF SYMBOLS 21 Reel eccentric removal roll 22 Hydraulic cylinder 23 Hydraulic source 24 Pressure adjustment valve 25 Incoming tension meter 26 Position detector 30 Pressing pressure adjustment apparatus 31 Reel eccentric removal apparatus 35 Rolling schedule setting apparatus

Claims (8)

In a control device for a rolling mill comprising a rolling mill and a tension reel that unwinds or winds the material to be rolled on at least one of the entry side and the exit side of the rolling mill,
A reel eccentric removal roll that applies a pressing force to the material to be rolled between the rolling mill and the tension reel,
The pressing force applied to the reel eccentricity removing roll is adjusted based on the deviation from the reference position of the reel eccentricity removing roll and the tension setting value set on the tension reel, and the target wound around the tension reel is adjusted. A control apparatus for a rolling mill, characterized by suppressing a fluctuation in tension applied to the material to be rolled due to a change in unwinding or winding speed of the material to be rolled, which occurs with the eccentricity of the rolled material. In the control apparatus of the rolling mill of Claim 1,
A rolling mill control apparatus, wherein a tension target value for a tension reel provided on an entry side and an exit side of the rolling mill and a tension target value for the reel eccentricity removal roll are different from each other. In the control apparatus of the rolling mill of Claim 1,
The rolling mill control device according to claim 1, wherein the rolling mill is a single stand rolling mill. In a control device for a rolling mill comprising a tandem rolling mill constituted by a plurality of rolling stands and a tension reel for unwinding or winding the material to be rolled on at least one of the entry side or the exit side of the rolling mill,
A reel eccentric removal roll that applies a pressing force to the material to be rolled between the tandem rolling mill and the tension reel,
The pressing force applied to the reel eccentricity removing roll is adjusted based on the deviation from the reference position of the reel eccentricity removing roll and the tension setting value set on the tension reel, and the target wound around the tension reel is adjusted. A control apparatus for a rolling mill, characterized by suppressing a fluctuation in tension applied to the material to be rolled due to a change in unwinding or winding speed of the material to be rolled, which occurs with the eccentricity of the rolled material. In the control apparatus of the rolling mill of Claim 4,
A roll for adjusting the plate length between the stands is provided between adjacent rolling stands, and the tension applied to the material to be rolled due to the plate speed fluctuation of the material to be rolled is adjusted by adjusting the pressing force applied to the roll. A control device for a rolling mill characterized in that In a control method of a rolling mill provided with a rolling reel and a tension reel that winds or unwinds the material to be rolled on at least one of the entry side or the exit side of the rolling mill,
A pressing force applied to a reel eccentricity removing roll that applies a pressing force to a material to be rolled between the rolling mill and a tension reel, a deviation from a reference position of the reel eccentricity removing roll, and a tension setting value set in the tension reel The tension fluctuations to the material to be rolled due to the unwinding of the material to be rolled or the fluctuation of the winding speed generated with the eccentricity of the material to be rolled wound on the tension roll A control method for a rolling mill, characterized by suppressing the rolling mill. In the control method of the rolling mill according to claim 6,
A rolling mill control method, wherein a tension target value for a tension reel provided on an entry side and an exit side of the rolling mill and a tension target value for the reel eccentricity removal roll are different from each other. In the control method of the rolling mill according to claim 6,
A rolling mill control method, wherein the rolling mill is a single stand rolling mill.

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