JPH0780506A - Row of steel strip rolling mills and operating method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] It relates to the strip rolling mill train and the operating method of the rolling mill train. More specifically, it enables efficient switching between precision rolling for adjusting the dimensions and regular rolling other than the precision rolling. . [Structure] In a strip rolling mill train, the main body of one rolling mill after rolling at least one stand for rolling rolled material into a circular cross section can be freely recombined, and a two-roll rolling mill and at least two three rolling mills are provided. A steel strip rolling mill row configured to be replaceable with a block type rolling mill consisting of roll rolling mills. And a method for operating the rolling mill train, in which a two-roll rolling mill is used for precision rolling, a two-roll rolling mill for non-precision rolling, or a block-type rolling mill consisting of at least two three-roll rolling mills.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip rolling mill and a strip rolling method, and more particularly to precision rolling with good dimensional and shape precision and appropriate non-precision rolling.

[0002]

2. Description of the Related Art Conventionally, a steel bar, which is a representative of a strip rolling equipment,
In a wire rod rolling facility, after heating a steel slab, a row of rough rolling mills, a row of intermediate rolling mills, and a row of each finishing rolling mill are sequentially rolled to obtain finished products. At that time, in order to obtain a product having strict dimensional accuracy by rolling in accordance with a request from a user, for example, there is a method of carrying out by a three-roll rolling mill having a small width expansion during rolling. In addition, a method of controlling the rolling position of each rolling mill and the tension of each rolling mill in a two-roll type rolling mill train based on the data of the outlet side dimension and shape of the finishing rolling mill is a special application by the applicant. It is disclosed in Japanese Patent Publication No. 3-23242.

However, when performing precision rolling with a three-roll rolling mill or a two-roll rolling mill, (1) as shown in FIG. 6, for example, when a three-roll rolling mill is installed behind the finishing rolling mill row, Requires a new installation space. (2) Since the torque and speed of the 3-roll rolling mill must be changed according to the product diameter, the 3-roll rolling mill cannot handle a wide range of torque and speed. ) In the case of straight bar steel finished by either the row of rough rolling mills or the row of intermediate rolling mills, precision rolling with a three-roll rolling mill behind the finishing row requires precision rolling after a certain time after split cutting. Therefore, problems such as temperature drop of the material occur.

In order to address these problems, when rolling a rolled product having strict size and shape accuracy, the unit type sizing mill consisting of a horizontal stand and a vertical stand must be replaced with a two-roll rolling mill for rolling. It is disclosed in JP-A-63-40601.

Further, when rolling products other than rolled products having strict dimensional accuracy, rolling of products of different sizes by the three-roll rolling method without changing the roll hole shape, that is, the same roll is used. Japanese Patent Publication No. 3-50601 filed by the applicant of the present invention discloses a method of rolling multi-sized products by adjusting the roll reduction.

As shown in FIG. 7, this method obtains a maximum diameter reduction rate of 15% by two-pass rolling with two 3-roll rolling mills. In the figure, 20 indicates a roll and 21 indicates a rolled material.

Further, a three-roll rolling machine which can be incorporated into a two-roll rolling machine was filed by the applicant of the present invention.
No. 3 (Fig. 8), and a rolling-down device for a three-roll rolling mill is disclosed in Japanese Utility Model Laid-Open No. 4-64407 filed by the present applicant (Fig. 9). In FIG. 8, 22 is the first three-roll rolling mill, and 23 is the second rolling mill.
Reference numeral 024 indicates a rolling roll.

The inventions disclosed in JP-B-3-50601, JP-A-4-200803, and JP-A-4-64407 relate to a three-roll rolling mill, but the rolling mill alone. The present invention relates to the elemental technology of the rolling method and apparatus, and does not disclose an entire system of a strip rolling mill train and an operating method using the rolling mill train.

[0009]

The above-mentioned prior art is not a proposal for improving productivity or for just-in-time delivery which has recently been requested by users.

In order to improve productivity and meet user's demands, the present invention eliminates or further develops the above-mentioned drawbacks of the prior art and makes full use of existing rolling lines to easily perform precision rolling and non-precision rolling. The present invention aims to complete an entire system of a rolling mill rolling mill train and a rolling mill train operating method capable of efficiently carrying out both of them.

[0011]

Means for Solving the Problems The present invention comprises (1) a combination of a pre-rolling mill that rolls into a circular cross section and a post-rolling mill that rolls into a circular cross-section through a rolling mill that continuously or non-circularly cross-section. Are arranged in at least one set, and a set of heated steel strips is selected according to the product size and finally finished-rolled to a strip steel product having a circular section by a post-rolling mill of the set. Among them, at least one main body of the latter stage rolling mill can be recombined, and a two-roll rolling mill and a block-type rolling mill composed of at least two three-roll rolling mills have an attachment part, a drive device joint part, etc. (2) A method of operating a strip rolling mill train as described in (1) above, in which the dimensions and shape of the rolled material are adjusted. Perform precision rolling Is a two-roll rolling mill that is a final rolling mill that performs final finishing rolling, and when performing normal rolling that does not adjust the size and shape of the rolled material, a two-roll rolling mill that is a final rolling mill that performs final finishing rolling is used. Or, a method of operating a row of strip rolling mills, characterized by incorporating a block-type rolling mill comprising at least two 3-roll rolling mills, (3)
A block type rolling mill composed of at least two three-roll rolling mills is incorporated in a latter-stage rolling mill for final finish rolling, and a rolling possible period of a steel strip product having the same size and shape specifications is provided twice or more per month. (2) The method for operating the strip rolling mill train described above.

[0012]

In general, as shown in FIG. 5, the strip rolling mill train includes a rough rolling mill train 2, an intermediate rolling mill train 3, and a finish rolling mill train 4, each having a plurality of stands. In the figure, 1 indicates a heating furnace and 5 indicates a dividing blade. FIG. 6 shows an example in which a sizing mill is separately installed in the conventional strip rolling equipment. In the figure, 6 indicates a 2-roll rolling stand.

Here, the designation of each rolling mill train refers to the small-diameter size for final finishing rolling in the finishing rolling mill train, which is conveniently divided and designated, and the large-diameter roll is rolled. In some cases, rolling may be completed in the row of rough rolling mills or the row of intermediate rolling mills to form the final product.

Further, in the case of obtaining a steel product having a circular cross section, the hole shape of the roll for the final rolling is naturally a shape for rolling the material into a circular cross section, and the roll set at the final stage of the rolling process is: Generally, the holes are rolled in a circular cross section, the holes are rolled in a non-circular cross section, and the holes are rolled into a final product having a circular cross section.

Usually, in a strip rolling mill train, since products of various diameter sizes are rolled on the same rolling line, a plurality of rolling mill trains arranged in the order of the hole type are arranged in the rolling mill train. There is.

In the first aspect of the present invention, of the above rolling mill set, the body of the rolling mill that performs the final finish rolling to obtain a bar steel product having a circular cross section can be freely recombined, and the mounting portion and the drive device joint portion can be interchanged. With a two-roll mill,
It is a strip steel rolling mill train in which a block type rolling mill composed of at least two three-roll rolling mills can be quickly replaced.

Here, the three-roll rolling mill is a rolling mill in which three rolling rolls are radially arranged at intervals of 120 degrees, and the block-type rolling mills are each shifted by 60 degrees on the rolling axis. It is composed of at least two three-roll rolling mills arranged. Further, the three-roll rolling mill is equipped with a rolling reduction mechanism.

Regarding the compatible mechanism of the rolling mill, for example, in the case of a block type rolling mill composed of two three-roll rolling mills, the invention described in Japanese Patent Laid-Open No. 4-200803 (FIG. 8) is adopted. The roll rolling mill has a rolling reduction mechanism realized by the invention (FIG. 9) described in, for example, Japanese Utility Model Laid-Open No. 4-64407.

A second aspect of the present invention is to carry out precision rolling for adjusting the size and shape of rolled material by the above-mentioned strip rolling mill, incorporating a conventional two-roll rolling mill stand into the finishing rolling mill, When performing normal rolling other than precision rolling, a conventional two-roll rolling mill or a block-type rolling mill composed of at least two or more three-roll rolling mills is incorporated into the finish rolling mill. Where at least 2
A normal rolling method other than precision rolling in a block-type rolling mill composed of three or more rolling mills is, for example,
The invention (Fig. 8) disclosed in Japanese Examined Patent Publication No. 3-50601 discloses that the material having a circular cross-section in the block-type stand is continuously passed through a rolling having a non-circular cross-section and the diameter reduction rate is 15% at the maximum. It is finished and rolled into a steel bar having a circular cross section.

According to the first and second inventions of the present invention described above, it is possible to extremely easily and quickly change the rolling size in the same rolling line, and productivity is improved, and at the same time, the third invention of the present application. By incorporating a block-type rolling mill consisting of at least two or more 3-roll rolling mills into the finishing rolling mill, and by allowing the rolling period of a steel strip product of the same size and shape specification to be twice or more per month, there is a demand from users. A strong just-in-time delivery is achieved.

[0021]

1 and 2 show a part of a rolling mill train centering on a rolling mill for final finishing rolling in a strip rolling mill train according to the present invention, in which the rolling mill is the center of the rolling mill. Is shown.

FIG. 1 shows an example in which a block type rolling mill composed of two 3-roll rolling mills is incorporated as a recombining rolling mill, and FIG. 2 is a 2-roll rolling mill as a recombining rolling mill. An intricate example is shown. In the figure, 7 is the stand immediately before the rearranging stand, 7'is the stand immediately after the rearranging stand, 10, 1
0'indicates a guidance device.

When precision rolling is not carried out by this reshuffling rolling mill, a block type rolling mill 8 composed of two 3-roll rolling mills is incorporated.

The rolling mill body 8 is fixed on a common sole plate 9.

FIG. 3 shows a front view of an example in which a block type rolling mill 8 composed of the two three-roll rolling mills is incorporated.

When performing precision rolling with a reshuffling rolling mill, 2
Block type rolling mill 8 consisting of three 3-roll rolling mills
Is pulled out from the sole plate 9 to the outside of the line, and the two-roll rolling mill 6 is incorporated into the line and fixed on the sole plate 9.

As described above, the two-roll rolling mill which can be replaced with the three-roll rolling mill block type rolling mill has a horizontal stand or a vertical stand, and has a structure compatible with the three-roll rolling mill block type stand 8. is there.

Needless to say, the rolling mill for precision rolling may be of a unit type having a horizontal stand and a vertical stand, as a matter of course, an appropriate type can be incorporated according to the precision rolling load.

FIG. 4 is a front view showing an example of the two-roll rolling mill. This figure shows the case where one 2-roll rolling mill 6 is incorporated, and the steel material rolled into an oval shape is subjected to precision rolling by a roll-hole type having a round shape.

This two-roll rolling mill 6 is a three-roll rolling block type rolling mill 8 with respect to the driving device and the sole plate.
Compatible with. That is, the sole plate 9, the guide device 10 such as the looper, and the drive device 11 of the 10 'are shared by the two-roll rolling mill and the three-roll rolling mill block rolling mill.

As for the 3-roll rolling block type rolling mill and the 2-roll rolling mill, an appropriate stand exchange system such as a crane lifting system and a rail exchange system can be adopted.

[0032]

As described in detail above, according to the present invention,
A two-roll rolling mill and a three-roll rolling mill equipped with a reduction adjusting mechanism for performing finish rolling and capable of rolling multi-sized products without changing rolls are configured to be replaceably incorporated into an existing rolling line. Therefore, the following excellent operational effects are achieved.

(1) It is possible to quickly switch between rolling by a three-roll rolling machine that rolls multi-size products without changing rolls and rolling of dimensional precision material by a two-roll rolling machine by changing the stand. It will be possible.

(2) The productivity is improved by swiftly changing the rolling size, and the just-in-time delivery to the user is achieved by rolling the steel products having the same size and shape specifications twice or more times a month. .

[Brief description of drawings]

FIG. 1 is a diagram showing a part of a rolling mill train centering on the rolling mill of an embodiment in which a main body of a rolling mill for final finish rolling in a strip rolling mill train according to the present invention is reconfigurable. The figure which shows the example which incorporated the block type rolling mill which consists of two 3-roll rolling mills as a replacement rolling mill.

FIG. 2 is a view showing a part of a rolling mill train centering on the rolling mill of the embodiment in which the main body of the rolling mill for final finish rolling in the rolling mill train according to the present invention is freely reconfigurable. The figure which shows the example which incorporated the 2-roll rolling mill as a replacement rolling mill.

FIG. 3 is a front view of a case where a block type rolling mill including the two three-roll rolling mills is incorporated.

FIG. 4 is a front view of the case where the two-roll rolling mill is incorporated.

FIG. 5 is a diagram showing an example of a conventional bar-rolling equipment line,
The figure which shows the example in which the sizing mill is not installed separately.

FIG. 6 is a diagram showing an example of a conventional bar-rolling equipment line,
The figure which shows the example in which the sizing mill is installed separately.

FIG. 7 is a diagram showing an example of Japanese Patent Publication No. 3-50601.

FIG. 8 is a diagram showing an embodiment of Japanese Patent Laid-Open No. 4-200803.

FIG. 9 is a diagram showing an example of Japanese Utility Model Laid-Open No. 4-64407.

[Explanation of symbols]

1 ... Heating furnace 2 ... Rough rolling mill row 3 ... Intermediate rolling mill row 4 ... Finishing rolling mill row 5 ... Dividing blade 6 ... 2 roll rolling mill stand 7 ... Stand just before recombining stand 7 '... Stand just after recombining stand 8 ... Block type stand composed of two 3-roll rolling mills 9 ... Sole plate 10, 10 '
Induction device 11 ... Drive device 20 ... Roll 21 ... Rolled material 22 ... First three-roll rolling machine 23 ... Second three-roll rolling machine 24 ... Rolling roll

Claims (3)

[Claims] 1. At least one set of a pre-rolling mill for rolling into a circular cross-section and at least one set of a post-rolling mill for rolling into a circular cross-section through a rolling mill for rolling continuously or non-circular in cross section is arranged, and a heating steel strip is provided. In the example of a strip rolling mill for final finishing rolling into a strip steel product having a circular cross section by the post-rolling mill of the set according to the product size, the main body of the post-rolling mill in at least one of the sets Can be recombined, and a two-roll rolling mill and a block-type rolling mill composed of at least two three-roll rolling mills can be exchanged by making the mounting portion and the drive device joint portion compatible with each other. A steel strip rolling mill train characterized by being present. 2. The method for operating a strip rolling mill train according to claim 1, wherein when performing precision rolling for adjusting the size and shape of rolled material, a two-roll rolling mill is used as a post-rolling mill for final finish rolling. When performing normal rolling in which the size and shape of the rolled material are not adjusted, the post-rolling mill for final finish rolling is a two-roll rolling mill or a block type composed of at least two three-roll rolling mills. A method for operating a row of rolling mills for rolling steel, characterized by incorporating a rolling mill. 3. A block-type rolling mill comprising at least two three-roll rolling mills is incorporated in a post-rolling mill for final finish rolling, and a rolling possible period for a steel strip product having the same size and shape specification is provided twice or more per month. 3. The method according to claim 2,
The method of operating the described row of steel strip rolling mills.