JPH0510166B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a rolling control device, and particularly to a rolling control device for rolling a billet by a group of rolling mills equipped with slotted rolls to produce a steel bar or wire rod product of a predetermined size and shape. The present invention relates to a rolling control device suitable for improving the dimensional accuracy of steel bars and wire rods by taking into account the configuration of a rolling mill group and the deformation state within the roll bite.

[Technical background of the invention and its problems]

Generally, steel bars and wire rod products are formed by continuous rolling using rolling mills equipped with slotted rolls. This groove rolling mill is a tandem mill consisting of many types of grooves, and the typical groove types are diamond groove, square hole, hexagonal hole, oval hole, and round hole. etc. are known. Such a groove rolling mill forms a steel bar or wire rod as a final product by sequentially passing a billet as a rolled material through a group of rolling mills equipped with various groove shapes.

In this case, rolling using slotted rolls mainly involves three-dimensional deformation, and since the rolling is performed in a direction perpendicular to the rolled material one after another, rolling using grooved rolls mainly involves two-dimensional deformation. However, it cannot be said that sufficient theory has been established to accurately calculate various rolling characteristic values including plastic deformation of rolled materials. For this reason, this is an area of rolling technology that requires further improvement in accuracy in the calculation and control of rolling settings.

As mentioned earlier, rolling with grooved rolls mainly involves three-dimensional deformation within the roll bite, and simultaneously the dimension in the rolling direction and the direction perpendicular to the rolling direction (hereinafter referred to as the width direction) are must be considered. However, in the rolling of steel bars and wire rods equipped with grooved rolls, the mill configuration is complicated, such as horizontal stands and vertical stands are arranged alternately, and the grooves on the rolling rolls built into the rolling stands are complicated. Due to the complexity of the shape itself, the actual situation is that active dimensional control with a higher level of control than in rolling plate materials is hardly performed. Therefore, there is a need for improvement in terms of product quality.

In addition, even when implementing the conventional concept of AGC (automatic gain control) using simple reduction control or tension control,
Although it is naturally possible to control dimensions in the rolling direction to the same degree as for sheet materials, the dimension in the width direction is a rolling process that mainly involves three-dimensional deformation, and considering that there is a large metal flow in the width direction as well as in the rolling direction, it is not necessarily guaranteed. Not as long. In other words, when dimensional control in the rolling direction is carried out, the dimension in the width direction varies depending on the amount of reduction, roll gap, and tension, and this is where the difficulty of guaranteeing the dimensional accuracy of rolling mills that manufacture steel bars and wire rod products arises. There is a need for some improvement.

[Purpose of the invention]

Therefore, an object of the present invention is to eliminate the drawbacks of the above-mentioned prior art, to control the dimensions in the width direction as well as in the rolling direction of steel bars and wire rods at the same time and at the same level, and to improve the precision of dimensional control in rolling steel bars and wire rods. The purpose of the present invention is to provide an improved rolling control device.

[Summary of the invention]

In order to achieve the above object, the present invention comprises: a first stand that rolls a material to be rolled in a first direction; a second stand that is adjacent to the upstream side of the stand that rolls a material in a second direction;
Further, a rolling means is provided with a third stand adjacent to the upstream side thereof and rolls in the first direction; a dimension control means for controlling the dimension of the material to be rolled in the first direction by the first stand to a target value; a second dimension control means for controlling the dimension of the rolled material in a second direction by the second stand to a target value; and a second dimension control means for controlling the rear tension of the first stand to the target value by controlling the speed of the second stand. By the first tension control means and the first control correction amount in the first dimension control means,
a first calculation means for correcting the tension target of the first tension control means; a second tension control means for controlling the rear tension of the second stand to a target value by controlling the speed of the third stand; and a second calculation means for correcting the tension target value of the second tension control means based on the control correction amount of the second dimension control means and the second control correction amount of the second dimension control means. A rolling control device is provided.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a rolling control device according to an embodiment of the present invention. The figure shows a three-stand configuration in which stand #i is a horizontal stand, stand #i-1 adjacent to it is a vertical stand, and stand #i-2 in front of it is a horizontal stand. In FIG. 1, the lowering devices 1 and 11 act on stand #i and stand #i-1, respectively. On the other hand, the automatic reduction direction dimension control devices 2 and 12 act on the #i stand and #i-1 stand, respectively, to automatically control the respective reduction direction dimensions. The calculation devices 3 and 13 each calculate the amount of correction of the tension target value. Drive motor 14, 24
drive stand #i-1 and stand #i-2, respectively. Speed control devices 15 and 25 control the rotational speeds of drive motors 14 and 24, respectively. The rotation speed calculating devices 16 and 26 calculate the roll rotation speed of each stand in order to realize a desired inter-stand tension value.

In Figure 1, Ti stands for stand #i and stand #i.
Setting tension value between -1, Ti-1 is stand #i-
1 and stand #i-2, 〓Si and 〓Si-1 are the reduction position target value correction amounts for stand #i and stand #i-1, respectively, 〓Ti and 〓Ti-1 are respectively for stand # i and the rear tension value correction amount of stand #i-1.

In this configuration, a method for controlling the effect of the stand #i in the exit side rolling direction and width direction simultaneously will be described next.

Control of the dimension in the rolling direction of stand #i is carried out by an automatic dimension control device 2 in the rolling direction and a rolling device 1. This control system is similar to the well-known AGC. As mentioned above, in the rolling of steel bars and wire rods, the metal flow in the width direction is large, but the dimension in the width direction also needs to be controlled at the same time. The roll target position correction amount Si due to the control of the dimension in the rolling direction of stand #i is input to the rolling device 1 and simultaneously input to the tension target value correction amount calculating device 3, 〓Ti=〓i〓Si... (1) The following calculation is performed. In equation (1), 〓Ti
is the correction amount of the tension setting target value Ti between stand #i and stand #i-1, and 〓 is a coefficient. (1)
By correcting the set tension value Ti by the tension correction amount 〓Ti in the formula, the dimensional variation in the width direction of the exit side of stand #i that is inevitably caused by 〓Si is offset. As a result, both the dimensions of the exit side of stand #i in the rolling direction and the width direction are controlled simultaneously. Specifically, the tension correction amount Ti determined by the tension target value correction amount arithmetic unit 3 is added to the tension setting value Ti by the adder 17, and the tension correction amount Ti is added to the tension setting value Ti by the adder 17 and the tension correction amount Ti is determined by the tension target value correction amount arithmetic unit 3.
The rotational speed calculation device 16 of FIG. The rotational speed calculation device 16 is connected to stand #i and stand #i-.
1, that is, the rear tension of stand #i is
The rotational speed of the drive motor 14 is controlled by the speed control device 15 so that Ti+=Ti. Thus,
Although the exit dimension of stand #i is controlled, the tension setting value 〓Ti or Ti+〓Ti for canceling the width direction dimensional variation of stand #i has a rolling limit value. Therefore, in order to precisely control the dimensions of the exit side of stand #i in the rolling direction and the width direction, it is necessary that the entrance side dimensions of stand #i fall within the control range. In stand #i-1, the material to be rolled on the entry side of #i is rolled down in the width direction. Control of the dimension in the rolling direction of stand #i-1 is carried out by an automatic dimension control device 12 in the rolling direction and a rolling device 11. Roll target position correction amount at this time〓Si−1
is input to the tension target value correction amount calculation device 13 of stand #i-1. In the tension target value correction amount calculating device 13, the target position correction amount of stand #i-1〓The tension conveyor correction amount carried out to guarantee the dimensional accuracy of the exit side of Si-1 and stand #i〓
Ti, that is, for stand #i-1, in order to offset the variation in the width direction dimension on the exit side of stand #i-1 due to both the forward tension target value correction amount〓Ti-1=〓i-1〓Si- 1-〓i-1〓Ti
...(2) The following calculation is performed. In equation (2), 〓Ti-1 is stand #i-1 and stand #i
-2 is the amount of modification of the tension setting value Ti-1, and 〓i-1 and 〓i-1 are coefficients. By correcting the tension setting value Ti-1 by the amount of correction in equation (2) Ti-1, the amount of rear tension correction for Si-1 and #i
The width direction dimension of the exit side of stand #i-1, that is, the dimension in the non-rolling direction, which inevitably occurs due to Ti, is controlled so that the variation in the dimension, which is the dimension in the rolling direction for stand #i, is offset, and therefore , dimensional control in the rolling direction and the width direction is also performed at the same time in stand #i-1. Specifically, the correction amount Ti-1 determined by equation (2) is added to the tension setting value Ti-1, and then input to the rotational speed calculation device 26 of stand #i-2, The drive motor 24 of stand #i-2 is controlled by the speed control device 25 so that the tension between stand #i-1 and stand #i-2, that is, the rear tension of stand #i-1, becomes Ti-1+=Ti-1.
The rotation speed will be controlled.

In addition, in the above embodiment, a three-stand configuration was used as an example, and an example was shown in which the automatic reduction direction dimension control device was installed in two stands, stand #i and stand #i-2, but stand #i-2 Alternatively, similar control can be achieved by installing a similar dimension control system upstream of stand #i-2. On the other hand, similar control can be applied when stand #i is the final stand.

FIG. 2 shows that in the configuration of FIG. 1, instead of inputting the correction amount 〓Ti to the tension target value correction amount calculation device 13, the roll target position correction amount 〓Si of stand #i is
FIG. 12 is a block diagram illustrating a case where .

〔Effect of the invention〕

As described above, according to the present invention, in the continuous rolling of steel bars and wire rods, the deformation characteristics caused by the grooved rolls incorporated in the stands are taken into account, and the deformation characteristics that occur inevitably due to dimensional control in the rolling direction and tension fluctuations between the stands are taken into account. It is possible to obtain a rolling control method and device that can offset dimensional fluctuations in the width direction, improve the dimensional accuracy of rolled products such as steel bars and wire rods, and ensure quality. Further, according to the present invention,
In order to control the tension between the stands, the speed of the stand on the upstream side is corrected, so at least the speed of the i-stand does not need to be changed. This has the effect of simplifying the configuration of the control system.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a rolling control device according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a modification of the present invention. 1, 11... Reduction device, 2, 12... Automatic reduction direction dimension control device, 3, 13... Arithmetic device, 1
6, 26...Rotation speed calculation device.

Claims (1)

[Claims] 1. A first stand that rolls the material to be rolled in a first direction, a second stand that is adjacent to the upstream side of the stand that rolls the material in the second direction, and a third stand that is adjacent to the upstream side of the stand that rolls the material in the first direction. a rolling means arranged with;
a first dimension control means for controlling a dimension of a rolled material in a first direction by the first stand to a target value; and a second dimension control means for controlling a dimension of a material to be rolled in a second direction by the second stand to a target value. a first tension control means for controlling the rear tension of the first stand to a target value by controlling the speed of the second stand; and a first control correction amount in the first dimension control means. , a first calculation means for correcting the tension target value of the first tension control means, and a second tension control means for controlling the rear tension of the second stand to the target value by controlling the speed of the third stand. 1st
and a second calculation means for correcting the tension target value of the second tension control means based on the control correction amount of the second dimension control means and the second control correction amount of the second dimension control means. Rolling control device.