JPH04361813A - Method for controlling biting speed of rolled stock in rolling line - Google Patents

Abstract

PURPOSE:To improve quality of a rolled stock by correcting a high set value for converging an amount of impact drop through a measured value of variation of a load torque. CONSTITUTION:An estimated amount of impact drop when each rolling mill bites a rolled stock and a high set value to converge it are set in a biting speed control of the rolled stock of a rolling line, the high set amount is corrected based on the measured value of variation of a load torque, a command value of the number of rotation is corrected when the rolled stock is bitten into each rolling mill corresponding to it. The difference between the high set amount and the amount of impact drop at the actual biting time can be inhibited automatically, bad effects given by the impact drop to the size and shape of the rolled stock are removed and high precision and high quality rolling can be actualized.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the biting speed of a rolled material in consideration of impact drops that occur when the rolled material is bitten in a rolling mill.

0002

[Prior Art] Generally, when a rolled material is bitten in a rolling mill, an impact drop as shown in FIG. After being bitten, a certain amount of recovery time will be required. The impact drop amount is expressed as the area between the rotation speed drop amount and the recovery time, that is, the area of the shaded portion in FIG.

[0003] Such impact drops have a negative effect on the rolled material, so in order to quickly resolve them, conventionally, when the rolled material is bitten, the rotational speed of the rolling mill is increased as shown in Fig. 4. A rotation speed command is given to the drive motor of the rolling mill so that the rolling rotation speed is set high and gradually reaches a predetermined rolling rotation speed.

0004

[Problem to be solved by the invention] However, conventionally,
The high setting amount (area of the shaded hatched area in Figure 3) due to the high setting rotation speed for impact drop compensation was manually set based on the operator's intuition and experience, so the high setting amount and the actual There was a difference between the impact drop amount at the time of biting, and it was undeniable that the tension and compressive force due to this difference had a negative effect on the dimensions and shape of the rolled material.

[0005] Here, when the higher setting amount>the impact drop amount, a tension force acts on the rolled material, while when the higher setting amount<the impact drop amount, a compressive force acts on the rolled material. The actual behavior of the motor rotation speed for each case of high setting amount > impact drop amount, high setting amount < impact drop amount, and high setting amount = impact drop amount is shown in Figures 5 (a), (b), and (c), respectively. show.

[0006] Furthermore, when loop control is performed on a rolling line, the amount of loop accumulation due to the impact drop when the rolled material is bitten is [(length of the rolled material itself located between the guide rolls) - (straight line between the guide rolls)] However, in this case as well, if there is a difference between the amount of loop accumulation corresponding to the loop height set by the operator and the amount of loop accumulation due to impact drop, this difference will increase the dimension of the rolled material. It was undeniable that this had a negative effect on the shape.

[0007] The present invention aims to solve these problems, and it is possible to reliably eliminate the adverse effects of impact drops on the dimensions and shape of the rolled material, thereby realizing high-precision and high-quality rolling. An object of the present invention is to provide a method for controlling the rolling material biting speed in a rolling line.

[0008]

[Means for Solving the Problems] In order to achieve the above object, the rolling material biting speed control method (claim 1) in a rolling line of the present invention provides: The drop amount and the initial value of the higher set amount to converge the estimated impact drop amount in each rolling mill are set in advance, and for the first rolled material, the first
Based on the ratio of the estimated impact drop amount of the rolling mill and the measured impact drop amount, the initial value of the higher setting amount in each rolling mill after the second rolling mill is corrected, and the rotation speed at the time of biting the rolled material in each rolling mill is adjusted. For the n-th rolled material, after determining the higher setting amount for each rolling mill based on the actual measured value of the impact drop amount for the n-1th rolled material, Based on the ratio of the impact drop amount of the first rolling mill and the impact drop amount actually measured for the n-th rolled material, the higher setting amount of each rolling mill after the second rolling mill is corrected and the rolling to each rolling mill is performed. It is characterized by changing the rotation speed command value when material is bitten. The estimated impact drop amount and the measured impact drop amount are the amount of rotational speed drop or the amount of change in load torque at the time of biting of the rolled material in each rolling mill (Claim 2).

[0009] Furthermore, the method (claim 3) of controlling the rolling material biting speed in a rolling line of the present invention includes: (1) setting in advance an estimated impact drop amount and loop height when rolling material is biting in each rolling mill; For the first rolled material,
Based on the ratio between the estimated impact drop amount of the rolling mill and the measured impact drop amount, the estimated impact drop amount at each rolling mill after the second rolling mill is corrected, and the estimated impact drop amount after the correction is calculated from the second rolling mill onwards. Based on the loop height of each rolling mill in The rotational speed command value during biting was output, and for the n-th rolled material, the estimated impact drop amount for each rolling mill was newly determined based on the measured impact drop amount for the n-1th rolled material. Then, based on the ratio between the new estimated impact drop amount of the first rolling mill and the measured impact drop amount, the new estimated impact drop amount of each rolling mill after the second rolling mill is corrected, and the revised estimate is calculated. Based on the impact drop amount and the loop height of each rolling mill after the second rolling mill, a higher set amount is determined to converge the estimated impact drop amount after the correction, and based on the higher set amount, the second rolling It is characterized by outputting a rotation speed command value for each rolling mill subsequent to the rolling mill when the rolled material is bitten. The estimated impact drop amount and the measured impact drop amount are the amount of rotational speed drop or the amount of change in load torque at the time of biting of the rolled material in each rolling mill (Claim 4).

0010

[Operation] In the above-mentioned control method of the present invention (claims 1 and 2), the high setting amount is adjusted as needed based on the actual measured value of the impact drop amount, and the rotation when the rolled material is bitten in each rolling mill is adjusted accordingly. Since the numerical command value is changed, the difference between the high setting amount and the actual impact drop amount during biting is automatically suppressed.

[0011] Furthermore, the control method of the present invention (claims 3 and 4)
Since the amount of loop accumulation that occurs when the rolled material is bitten is determined by the impact drop amount, in order to produce the amount of loop accumulation that corresponds to the preset loop height when the rolled material is bitten, this impact drop amount must be adjusted. All you have to do is control. In order to control the amount of impact drop,
The estimated impact drop amount is corrected based on the measured value of the impact drop amount, and the estimated impact drop amount - higher setting amount is taken as the apparent impact drop amount.In order to control this apparent impact drop amount, the higher setting amount is adjusted at any time. is determined, and the difference between the amount of loop accumulation corresponding to a preset loop height and the amount of loop accumulation due to impact drop is automatically suppressed.

0012

[Example] Hereinafter, embodiments of the present invention will be explained with reference to the drawings. Fig. 1 explains the procedure of the rolling material biting speed control method (claims 1 and 2) in a rolling line as a first embodiment of the present invention. In FIG. 1, 1 is a rolled material, 2 is a rolling mill (stand; indicated as std in the figure) for rolling this rolled material 1, and 3 is a device that drives this rolling mill 2. 4 is a pulse generator (PLG) that detects the rotation speed of this motor 3, 5-1 to 5
-N is a motor control device for controlling the operation of the motor 3 of each of the N rolling mills 2; 6 is a storage unit that stores master data obtained by calculation etc. in advance as a table; In this example, the load torque of each rolling mill 2 according to the steel type, material temperature, pass schedule, etc., and the estimated impact drop amount of each rolling mill 2 (amount of rotational speed drop or load torque change amount when rolled material is bitten) , an initial value of a higher set amount (higher set rotation speed) for converging the estimated impact drop amount in each rolling mill, etc. are stored as master data.

Further, 7 is a load torque calculation unit that calculates and actually measures the load torque of each motor 3 as an actual measured value of impact drop amount (it may also be a rotational speed detection unit that detects the amount of rotational speed drop as an actual measured value of impact drop amount). ,
8 is a divider that calculates the ratio between the estimated impact drop amount of the first rolling mill 2 and the measured impact drop amount, and 9 is a higher setting of the ratio from this divider 8 and each rolling mill 2 after the second rolling mill 2. A multiplier 10 corrects each initial value of the higher setting amount by multiplying the initial value of the higher setting amount by the initial value of the higher setting amount.
This is a higher set rotation speed calculation unit that calculates and changes the rotation speed command value when the rolled material is bitten, and outputs it to each motor control device 5-2 to 5-N.

Now, the procedure of the method of this embodiment will be explained below with reference to FIG. An initial value of a higher setting amount for converging is preset in the storage unit 6 by the operator.

For the first rolled material 1, during rolling, the load torque calculation section 7 obtains the load torque change amount as the actual measurement value of the impact drop amount in the first rolling mill 2, and the actual measurement value and the 1 and the estimated impact drop amount of rolling mill 2 is determined by a divider 8. The obtained ratio is applied to each rolling mill 2 after the second rolling mill by a multiplier 9.
The initial value of the high setting amount is multiplied by the initial value of the high setting amount, and the initial value of the high setting amount is corrected. Based on the corrected high setting amount, the high setting rotation speed calculation unit 10 calculates the number of rolling mills from the second to the Nth rolling mills. The rotational speed command value when the rolled material is bit into 2 is corrected/changed and outputted to each motor control device 5-2 to 5-N.

[0016] The second and subsequent rolling materials 1, for example n (n≧2
) Regarding the actual rolled material, first, based on the actual measurement value of the impact drop amount for the rolled material 2 up to the n-1th roll, the higher setting amount ( (higher setting rotation speed) (set according to lot). At this time, the average value of the amount of rotational speed drop or the amount of change in load torque from the first to (n-1)th rotation may be used.

[0017] Then, almost like the first case, n-
The impact drop amount of the first rolling mill 2 up to the first rolling mill,
The ratio to the impact drop amount (in this example, the amount of change in load torque) actually measured for the n-th rolled material 1 is determined by the load torque calculation unit 7 and the divider 8, and the ratio and
The high setting amount is corrected by multiplying the high setting amount in each rolling mill 2 after the second rolling mill in the multiplier 9, and based on this corrected high setting amount, the high setting rotation speed calculating section In step 10, the rotational speed command value when biting the rolled material to each of the second to Nth rolling mills 2 is corrected/changed (correction for each material).
, is output to each motor control device 5-2 to 5-N.

As described above, according to the control method of the first embodiment of the present invention, the high setting amount is corrected at any time based on the actual measured value of the load torque change amount, and each high setting amount is adjusted according to the corrected high setting amount. Since the rotation speed command value for the rolling material biting to the motor control device 3 of the rolling mill 2 is corrected and changed, the difference between the higher setting amount and the actual impact drop amount when biting is suppressed automatically. As a result, the negative influence of impact drops on the dimensions and shape of the rolled material is reliably removed, making it possible to achieve high-precision and high-quality rolling.

Next, a method for controlling the biting speed of rolled material (claims 3 and 4) as a second embodiment of the present invention will be explained. FIG. 2 is a schematic explanatory diagram for explaining the steps of the method. , since the same reference numerals as those already described indicate the same parts, the explanation thereof will be omitted.

In FIG. 2, reference numeral 6A denotes a storage section that stores master data obtained through calculations etc. in advance as a table. The load torque of the mill 2, the estimated impact drop amount of each rolling mill 2 (amount of rotation speed drop or amount of change in load torque when rolling material is bitten), loop height, etc. are stored as master data. 9A
is a multiplier that corrects each estimated impact drop amount by multiplying the ratio from the divider 8 by the estimated impact drop amount in each rolling mill 2 after the second rolling mill, and 11 is a multiplier according to steps S1 to S5 as described later. A higher set rotation speed calculation unit 11a is a subtracter that constitutes the higher set rotation speed calculation unit 11, which calculates a higher set rotation speed based on the loop height and the estimated impact drop amount.

The procedure of the method of the second embodiment of the present invention will be explained below with reference to FIG. 2. First, the estimated impact drop amount and loop height at the time of biting of the rolled material in each rolling mill 2 are stored by the operator It is set in advance in section 6A.

[0022] In the high set rotation speed calculating section 11, the amount of loop accumulation is calculated based on the loop height set in step S1 (step S2), and the apparent impact drop amount S3 is calculated ( Step S3)
. Then, by calculating the difference between the estimated impact drop amount and the apparent impact drop amount using the subtractor 11a, a higher set amount is determined (step S4), and based on this higher set amount, the A higher set rotation speed is calculated (step S5).

Regarding the first rolled material 1, during rolling, the load torque calculation section 7 obtains the load torque change amount as the actual measurement value of the impact drop amount in the first rolling mill 2, and calculates the amount of change in the load torque by the load torque calculating section 7, and calculates the amount of change in the load torque from the first rolling mill 2. The ratio with the estimated impact drop amount of the machine 2 is determined by the divider 8. The obtained ratio is multiplied by the loop-controlled estimated impact drop amount of the stand in each rolling mill 2 after the second rolling mill to correct each estimated impact drop amount. The estimated impact drop amount after correction is inputted to the higher setting rotation speed calculation unit 11 together with the preset loop height, and the estimated impact drop amount after correction is converged according to the same procedure as steps S1 to S5 described above. Based on the high setting amount, the rotational speed command value when biting the rolled material to each of the second to Nth rolling mills 2 is corrected and changed, and each motor control device 5 -2~5
-N is output.

[0024] The second and subsequent rolling materials 1, for example n (n≧2
) Regarding the actual rolled material, first, the estimated impact drop amount in each rolling mill 2 is calculated based on the actual measurement value of the impact drop amount for the rolled material 2 up to the n-1th roll, and the amount of rotational speed drop or load torque change. A new decision will be made. At this time, the average value of the amount of rotational speed drop or the amount of change in load torque from the first to (n-1)th rotation may be used.

[0025] Then, in almost the same way as the first case, the first
The ratio between the new estimated impact drop amount of the rolling mill 2 and the actually measured impact drop amount (in this example, the amount of change in load torque) for the n-th rolled material 1 is calculated by the load torque calculation unit 7 and the divider 8. The estimated impact drop amount is corrected by multiplying the ratio by the new estimated impact drop amount in each rolling mill 2 after the second rolling mill 2, and the estimated impact drop amount is corrected. Based on the amount and the preset loop height, the rotation speed command value at the time of biting the rolled material into each of the second to Nth rolling mills 2 is corrected or changed in the higher set rotation speed calculation section 11. , is output to each motor control device 5-2 to 5-N.

As described above, according to the control method of the second embodiment of the present invention, the estimated impact drop amount is corrected based on the measured value of the impact drop amount, and the estimated impact drop amount - the higher set amount is changed from the apparent As the impact drop amount, by determining a higher set amount at any time to control this apparent impact drop amount, the amount of loop accumulation corresponding to the preset loop height and the amount of loop accumulation due to impact drop can be determined. As in the first embodiment, the negative influence of impact drops on the dimensions and shape of the rolled material is reliably eliminated, and high precision and high quality rolling can be achieved.

[0027]

As described in detail above, according to the method for controlling the rolling material biting speed in a rolling line of the present invention (claims 1 and 2), the higher setting amount is set based on the actual measured value of the amount of change in load torque. The system is configured to modify and change the rotational speed command value for each rolling mill when the rolled material is bitten in accordance with the corrected high setting amount, so that the impact of the high setting amount and the actual biting can be adjusted. This has the effect of automatically suppressing the difference between the drop amount and reliably eliminating the adverse effect that impact drops have on the dimensions and shape of the rolled material, thereby realizing high-precision, high-quality rolling.

Further, according to the rolling material biting speed control method in a rolling line of the present invention (claims 3 and 4), the estimated impact drop amount is corrected based on the actually measured value of the impact drop amount, and the estimated impact drop amount is - The higher setting amount is the apparent impact drop amount, and in order to control this apparent impact drop amount, the higher setting amount is determined at any time, so the loop accumulation corresponding to the preset loop height The difference between the amount of loops accumulated due to impact drops and the amount of loops accumulated due to impact drops can be automatically suppressed, and the negative effects of impact drops on the dimensions and shape of rolled materials can be reliably removed, resulting in high-precision, high-quality rolling. There is.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram for explaining the procedure of a rolling material biting speed control method in a rolling line as a first embodiment of the present invention.

FIG. 2 is a schematic explanatory diagram for explaining the procedure of a rolling material biting speed control method in a rolling line as a second embodiment of the present invention.

FIG. 3 is a graph for explaining an impact drop.

FIG. 4 is a graph for explaining a high setting amount.

FIGS. 5(a) to 5(c) are graphs showing the actual behavior of the motor rotation speed according to a high setting amount.

[Explanation of symbols]

1 Rolled material 2 Rolling machine 3 Motor 4 Pulse generators 5-1 to 5-N Motor control device 6, 6A
Storage unit 7 Load torque calculation unit (rotation speed drop detection unit) 8
Divider 9, 9A Multiplier 10, 11 High setting rotation speed calculating section 11a
subtractor

Claims (4)

[Claims] 1. A method for controlling the biting speed of rolled material in a rolling line consisting of a plurality of rolling mills, comprising: an estimated impact drop amount when biting the rolled material in each of the rolling mills;
Presetting an initial value of a high setting amount for converging the estimated impact drop amount in each of the rolling mills,
Regarding the first rolled material, based on the ratio of the estimated impact drop amount of the first rolling mill of the rolling line and the measured impact drop amount, The initial value of the set amount is corrected, and the rotation speed command value when biting the rolled material to each rolling mill after the second rolling mill is changed, and for the nth (n≧2) rolled material, After determining the higher set amount for each of the rolling mills based on the measured value of the impact drop amount for the rolled material up to the Based on the ratio with the impact drop amount actually measured for the rolled material, the higher setting amount in each rolling mill after the second rolling mill of the rolling line is corrected, and the rolling to each rolling mill after the second rolling mill is adjusted. A method for controlling the speed of rolling material biting in a rolling line, characterized by changing a rotational speed command value at the time of material biting. 2. The estimated impact drop amount and the measured impact drop amount are set as the amount of rotational speed drop or the amount of load torque change at the time of biting of the rolled material in each of the rolling mills. A method for controlling the biting speed of rolled material in the rolling line described above. 3. In a method for controlling the rolling material biting speed in a rolling line consisting of a plurality of rolling mills, an estimated impact drop amount and loop height at the time of rolling material biting in each of the rolling mills are set in advance, and the first Regarding the rolled material, based on the ratio of the estimated impact drop amount of the first rolling mill of the rolling line and the measured impact drop amount,
Correcting the estimated impact drop amount in each rolling mill after the second rolling mill of the rolling line, and based on the corrected estimated impact drop amount and the loop height of each rolling mill after the second rolling mill. , determine a higher set amount for converging the estimated impact drop amount after the correction, and based on the higher set amount, set a rotation speed command value at the time of biting of the rolled material to each rolling mill after the second rolling mill. and output n(n
≧2) For the main rolled material, after newly determining the estimated impact drop amount in each of the above-mentioned rolling mills based on the actual impact drop amount measurements for the (n-1)th rolled material, the first rolling mill Based on the ratio of the new estimated impact drop amount and the measured impact drop amount, the new estimated impact drop amount in each rolling mill after the second rolling mill is corrected, and the estimated impact drop amount after the correction is Based on the loop height of each rolling mill after the second rolling mill, determining a higher setting amount for converging the estimated impact drop amount after correction,
A method for controlling a rolling material biting speed in a rolling line, comprising outputting a rotation speed command value for rolling material biting to each rolling mill after the second rolling mill based on the higher setting amount. 4. The estimated impact drop amount and the measured impact drop amount are set as an amount of rotational speed drop or a change in load torque at the time of biting of the rolled material in each of the rolling mills. A method for controlling the biting speed of rolled material in the rolling line described above.