JP2004290979A - Rolling method for thick steel plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling method with which even in the case of setting a rolling-reduction schedule for completing the last pass at non-desirable stage in a reverse rolling mill, the lowering of operating ratio of the reverse rolling mill is restrained and the lowering of productivity of a thick steel plate can be restrained. <P>SOLUTION: In the case of setting the rolling-reduction schedule for completing the reverse-rolling at the desirable stage in the reverse rolling mill, the reverse-rolling is performed according to the set rolling-reduction schedule. Then, in the case of setting the rolling-reduction schedule for completing the reverse-rolling at the non-desirable stage in the reverse rolling mill, this rolling schedule supplements one pass at a step for broadside rolling. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００３２】
表１に示すように、連続鋳造法で製造した鋼スラブ１（厚さ ２１５ｍｍ）を長手方向（すなわち鋳込み方向）に平行にリバース圧延機に装入し、第１パスで板厚を １９９．６ｍｍとした。第１パスに要した時間は ２．２秒であった。次いで圧延ロールの間隔を調整（所要時間 ５．３秒）して第２パスを施し、板厚を １８４．２ｍｍとした。第２パスに要した時間は ２．６秒であった。これらの第１〜２パスが成形圧延である。
【００３３】
成形圧延の終了後（すなわち第２パスの終了後）、圧延ロールの間隔を調整し、かつ圧延材２を９０°回転して、長手方向に対して垂直な方向にリバース圧延機に装入し、第３パスを施した。この第２パスと第３パスのパス間の所要時間は、１４．９秒であった。第３パス終了後の板厚は １８３．１ｍｍ、第３パスに要した時間は １．１秒であった。表１では第３〜７パスが幅出圧延である。
【００３４】
表１中の第４パス以降の記載については、上記と同様にデータを示しているので、詳細な説明を省略する。
幅出圧延の終了後（すなわち第７パスの終了後）、圧延ロールの間隔を調整し、かつ圧延材２を再度９０°回転して、長手方向に平行にリバース圧延機に装入して、第８パスを施した。この第７パスと第８パスのパス間の所要時間は、１３．５秒であった。第８パス終了後の板厚は９５．４ｍｍ、第８パスに要した時間は ２．２秒であった。表１では第８〜１５パスが厚出圧延である。
【００３５】
このようにして発明例では第１５パスが終了すると、１３．１ｍｍの厚さに仕上げられた厚鋼板３はリバース圧延機の後面に排出された。このリバース圧延に要した時間は、表１に示す通り、合計 １２７．４秒であった。
一方、比較例１として、連続鋳造法で製造した鋼スラブ（厚さ２１５ｍｍ ）をリバース圧延機に装入して、図２に示すような３段階圧延を行ない、厚鋼板（厚さ１３．１ｍｍ）を製造した。その際、従来から適用されているスケジュール計算にしたがって圧下スケジュールを設定して、リバース圧延機の前面で厚出圧延を終了させた。
【００３６】
図２に示す比較例１の各パス終了後の板厚（ｍｍ），各パスの所要時間（秒），パス間の所要時間（秒）は表２に示す通りである。
【００３７】
【表２】

【００３８】
表２に示したパス終了後の板厚，パスに要する時間，パス間の所要時間は、表１と同様にデータを示しているので、詳細な説明を省略する。
表２では第１〜２パスが成形圧延、第３〜６パスが幅出圧延、第７〜１４パスが厚出圧延である。
このようにして比較例１では第１４パスが終了すると、１３．１ｍｍの厚さに仕上げられた厚鋼板３はリバース圧延機の前面に排出された。そこで第１４パスの終了後、ダミーパスを追加して、厚鋼板３をリバース圧延機の後面に排出した。この圧延に要した時間は、表２に示す通り、ダミーパスを含めて合計 １２８．９秒であった。
【００３９】
さらに、比較例２として、連続鋳造法で製造した鋼スラブ（厚さ２１５ｍｍ ）をリバース圧延機に装入して、図３に示すような３段階圧延を行ない、厚鋼板（厚さ１３．１ｍｍ）を製造した。なお図３の圧下スケジユールは、図２の厚下スケジュールに対して厚出圧延の段階で１パス追加して、リバース圧延機の後面で厚出圧延を終了させたものである。
【００４０】
図３に示す比較例２の各パス終了後の板厚（ｍｍ），各パスの所要時間（秒），パス間の所要時間（秒）は表３に示す通りである。
【００４１】
【表３】

【００４２】
表３に示したパス終了後の板厚，パスに要する時間，パス間の所要時間は、表１と同様にデータを示しているので、詳細な説明を省略する。
表３では第１〜２パスが成形圧延、第３〜６パスが幅出圧延、第７〜１５パスが厚出圧延である。
このようにして発明例では第１５パスが終了すると、１３．１ｍｍの厚さに仕上げられた厚鋼板３はリバース圧延機の後面に排出された。このリバース圧延に要した時間は、表３に示す通り、合計 １３０．３秒であった。
【００４３】
発明例と比較例１，２について、リバース圧延に要した時間を比べると、発明例は １２７．４秒であったのに対して、比較例１，２は １２８．９〜１３０．３ 秒であった。したがって本発明を適用することによって、常にリバース圧延機の後面で最終パスを終了させ、かつ鋼スラブから厚鋼板を製造するまでの所要時間を短縮できることが確かめられた。
【００４４】
【発明の効果】
本発明によれば、常にリバース圧延機の所望の面で最終パスを終了させることができる。特に後面で最終パスを終了させた場合は、鋼スラブから厚鋼板を製造するまでの所要時間を短縮できる。その結果、リバース圧延機の稼動率の低下を抑制し、厚鋼板の生産性の低下を抑制でき、しかもリバース圧延中の温度低下による圧延材の収縮を抑制して厚鋼板の寸法精度の向上も達成できる。
【図面の簡単な説明】
【図１】本発明の圧下スケジュールの例を模式的に示す図である。
【図２】従来の圧下スケジュールの例を模式的に示す図である。
【図３】圧下スケジュールの他の例を模式的に示す図である。
【符号の説明】
１ 鋼スラブ
２ 圧延材
３ 厚鋼板[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rolling method for manufacturing a thick steel plate by charging a steel slab into a reverse rolling mill.
[0002]
[Prior art]
When manufacturing a thick steel plate, after heating a steel slab serving as a material, rolling is repeatedly performed to perform reduction, thereby manufacturing a thick steel plate having a predetermined thickness.
That is, a high-temperature steel slab is first charged into a reverse rolling mill, reduced (also referred to as a pass), and discharged to the opposite side of the reverse rolling mill. Here, the charging side of the first pass in the reverse rolling mill is referred to as a front surface, and the discharge side of the first pass is referred to as a rear surface.
[0003]
Further, a steel slab subjected to a reduction is referred to as a rolled material in order to distinguish it from a steel slab as a material. Furthermore, what finished to predetermined | prescribed product dimensions by rolling is described as a thick steel plate.
When the steel slab is subjected to the first pass and discharged to the rear face of the reverse rolling mill, the interval between the rolling rolls is adjusted, the transport rollers are reversed, and the rolled material is charged from the rear face of the reverse rolling mill and the second pass is performed. The pressure is reduced. Next, after adjusting the interval between the rolling rolls, the conveying rollers are reversed, the rolled material is loaded from the front of the reverse rolling mill, and the third pass is reduced.
[0004]
In this way, the rolling is repeatedly performed to finish a steel plate having a predetermined product size, and is sent to a subsequent process.
The amount of reduction in each pass from the steel slab to the thick steel plate is set by calculation based on operation results and experimental results, and the series of reduction settings is called the reduction schedule or pass schedule . However, here, it is described as a rolling schedule.
[0005]
Regarding the setting of the rolling schedule, a method of calculating a schedule using a calculation formula of a load model (for example, see Patent Literature 1) and a method of performing a schedule calculation by predicting a plate shape (for example, see Patent Literature 2) have been proposed. ing. In plate rolling, rolling is performed by adjusting the interval between rolling rolls according to a rolling schedule set by a method suitable for the reverse rolling mill to be used.
[0006]
These multiple passes are divided into three stages according to the purpose. First, at the stage called forming rolling, slabs usually have thickness deviations such as traces on the surface, so make the slab thickness uniform before tent rolling, and increase the tentering accuracy in the subsequent tent rolling. Perform for purpose. In some cases, rolling is performed with a predetermined thickness difference in the length direction in the final pass to improve the planar shape.
[0007]
When the forming rolling is completed, the rolling material is rotated by 90 ° in a horizontal plane to obtain a predetermined rolling width, and the width rolling is performed to perform rolling in a direction perpendicular to the forming rolling. Also in this case, rolling may be performed with a predetermined thickness difference in the length direction in the final pass in order to improve the planar shape. When the tentering rolling is completed, finish rolling is performed in which the steel sheet is again rotated by 90 ° in a horizontal plane and rolled to a predetermined thickness.
[0008]
Usually, the three-stage rolling of the above-described forming rolling, width rolling, and thickness rolling is widely performed. However, depending on the material and dimensions of the steel slab, rolling may be performed in two stages.
In the two-stage rolling, forming rolling is omitted, and width rolling and thickness rolling are performed. That is, similarly to the three-stage rolling, in the width rolling, the steel slab is loaded into the reverse rolling mill in a direction perpendicular to the longitudinal direction of the steel slab, and in the thick rolling, the material is loaded into the reverse rolling mill in parallel with the longitudinal direction of the steel slab. And rolling is performed.
[0009]
In performing such three-stage or two-stage rolling, if rolling is performed according to a set rolling schedule, the final pass may be completed on the rear side of the reverse rolling mill or may be completed on the front side. .
When the final pass is completed, the steel plate is fed to a post-process (ie, a straightening machine called a leveler). Since this straightening machine is provided on the rear face of the reverse rolling mill, when a rolling schedule in which the final pass ends on the rear face of the reverse rolling mill is set, the steel plate can be normally fed to the straightening machine without any trouble.
[0010]
However, when a rolling schedule in which the final pass ends at the front of the reverse rolling mill is set, in order to feed the thick steel plate to the straightening machine, the steel sheet is passed from the front to the rear of the reverse rolling mill without rolling. There must be. This is called a dummy pass, in which the distance between the rolling rolls is made larger than the thickness of the thick steel plate, and the thick steel plate is passed without any reduction.
[0011]
If a dummy pass is added subsequent to the final pass in this way, a reduction in the operation rate of the reverse rolling mill, that is, a reduction in productivity of thick steel plates is caused.
In other words, the final pass in the plate rolling is a pass belonging to the step of the thick rolling, and as described above, is loaded into the reverse rolling mill in parallel with the longitudinal direction. At this time, since the thick steel plate is the longest in the process from the steel slab to the thick steel plate, the time required for passing the thick steel plate in the longitudinal direction becomes long. Further, the time required for increasing the interval between the rolling rolls is added, so that the dummy pass requires a long time. As a result, the operation rate of the reverse rolling mill is reduced, that is, the productivity of the steel plate is reduced.
[0012]
Moreover, since the thickness measuring device used for the automatic control of the reverse rolling mill is usually installed on the rear face of the reverse rolling mill, if the rolling schedule in which the final pass ends at the front face of the reverse rolling mill is set, The thickness control (monitoring AGC) that controls the roll interval by feeding back the difference between the measured value and the target value cannot be applied. As a result, there arises a problem that the dimensional accuracy of the thick steel plate is reduced.
[0013]
On the other hand, depending on the components and dimensions of the rolled material, the tip may be deformed during rolling. If the deformation is a warpage, transport on the line is possible, but depending on the degree of the warp, the straightening machine may not stop the line and stop the line. On the other hand, if the final pass is completed on the front side of the reverse rolling mill, even if a dummy pass is used, the straightening machine can be bitten from the rear end portion where there is no deformation, so that a line stop can be avoided.
[0014]
That is, both the rear surface and the front surface of the reverse rolling mill may be desired. However, there was a problem that rolling was not necessarily completed on a desired surface of the reverse rolling mill due to the rolling schedule.
[0015]
[Patent Document 1]
JP-A-59-10408 [Patent Document 2]
JP 2001-212607 A
[Problems to be solved by the invention]
The present invention solves the above-described problems, and when rolling and manufacturing a thick steel plate, even when a rolling schedule in which the final pass is completed on an undesirable surface of the reverse rolling mill is set, the reverse rolling mill is An object of the present invention is to provide a rolling method capable of suppressing a decrease in the operation rate and suppressing a decrease in productivity of a thick steel plate.
[0017]
In addition, by applying the rolling method of the present invention, it is possible to achieve an improvement in dimensional accuracy of a thick steel plate.
[0018]
[Means for Solving the Problems]
The present invention relates to a rolling method for producing a thick steel sheet by performing a three-stage rolling of forming rolling, tent rolling and bulging rolling, or a two-stage rolling of tent rolling and bulging rolling using a reverse rolling mill. If the rolling schedule in which the thickening rolling is completed on the desired surface of the rolling mill is set, reverse rolling is performed according to the set rolling schedule, and the rolling schedule in which the thickening rolling is completed on the undesired surface of the reverse rolling mill. Is set, this is a method of rolling a thick steel plate in which reverse rolling is completed on a desired surface of a reverse rolling mill by adding one pass at the stage of tentative rolling.
[0019]
In the above-mentioned invention, as a preferred mode for improving the thickness accuracy, it is preferable that a desired surface is a rear surface of the rolling mill.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described in detail when a desired surface is a rear surface.
In the present invention, the rolling schedule is set according to the schedule calculation conventionally applied in the reverse rolling mill to be used. As a result, when a rolling schedule in which the final pass of the thick rolling is completed on the rear surface of the reverse rolling mill is set, rolling is performed according to the rolling schedule. That is, since the thick steel plate is discharged to the rear surface after the end of the thick rolling, the thick steel plate can be fed to the straightening machine without any trouble.
[0021]
However, as a result of setting the reduction schedule according to the schedule calculation conventionally applied, as shown in FIG. 2, when the reduction schedule in which the final pass of the thickening rolling ends at the front of the reverse rolling mill is set, The steel sheet 3 is discharged to the front side, and the thick rolling is completed. FIG. 2 shows an example of rolling in which three-stage rolling of forming rolling, width rolling and thickness rolling is performed. In FIG. 2, forming rolling includes first and second passes (total 2 passes), tentering rolling includes third to sixth passes (total 4 passes), and thickening rolling includes 7-14 passes (total 8 passes).
[0022]
In FIG. 2, in order to feed the steel plate 3 discharged to the front of the reverse rolling mill to the straightening machine, a dummy pass shown by a dotted line must be added following the 14th pass (that is, the final pass). . In the dummy pass, the gap between the rolling rolls is larger than the thickness of the thick steel plate 3 to reduce the pressure. Therefore, it takes a long time to pass the thick steel plate 3 in the longitudinal direction in the dummy pass.
[0023]
Therefore, in the present invention, the drafting schedule is set according to the schedule calculation conventionally applied, and when the drafting schedule in which the final pass of the thickening rolling ends at the front of the reverse rolling mill is set, the tentative rolling is performed. Rolling is performed by adding one pass at the stage. FIG. 1 shows an example of the rolling schedule. That is, one pass is added to the rolling schedule of FIG. 2 set by the conventional schedule calculation at the stage of the tentative rolling. Therefore, in FIG. 1, forming rolling is performed in the first and second passes (total 2 passes), width rolling is performed in the third to seventh passes (total 5 passes), and thickening rolling is performed in the 7th to 15th passes (total 8 passes). Has become.
[0024]
In the tent rolling, the steel slab 1 is charged into a reverse rolling mill in a direction perpendicular to the longitudinal direction. Therefore, as shown in FIG. 1, the time required for one pass added at the stage of the tent rolling is shorter than the time required for the dummy pass added after the end of the thick rolling as shown in FIG. The rolled material 2 can be passed in time.
In addition, the manufacturing method of the steel slab 1 to which the present invention is applied is not limited to a specific technique, and the present invention can be applied to a steel slab 1 manufactured by a conventionally known continuous casting method, ingot making method, or the like without any trouble.
[0025]
When one pass is added at the tent rolling stage in this way, the rolling reduction of each pass of the tent rolling decreases. As a result, when the rolling reduction is too small, the operation of the reverse rolling mill is hindered. In other words, since the reverse rolling mill operates while measuring the rolling load using a load cell or the like, when the rolling reduction is small, the rolling load decreases, and an error occurs in the measurement of the rolling load or the measurement is difficult. It becomes. In such a case, tentative rolling is performed according to the rolling schedule set in the schedule calculation that has been conventionally applied, and a dummy pass is added after fining rolling is completed, and the rolled material is not subjected to rolling. Pass through 2.
[0026]
The time required for the dummy pass added after the end of the tent rolling is shorter than the time required for the dummy pass added after the end of the thick rolling as shown in FIG. Can be. After the completion of the dummy pass, the rolled material 2 is rotated by 90 ° to perform thick rolling.
As described above, when the present invention is applied when rolling is performed to manufacture the thick steel plate 3, the final pass is always completed at the rear surface of the reverse rolling mill, and until the thick steel plate 3 is manufactured from the steel slab 1. The required time can be reduced. As a result, a reduction in the operation rate of the reverse rolling mill can be suppressed, and a reduction in the productivity of the thick steel plate 3 can be suppressed. Further, the shrinkage of the rolled material 2 due to a temperature decrease during the reverse rolling is suppressed, and the dimensional accuracy of the thick steel plate 3 can be suppressed. Can also be improved.
[0027]
FIG. 1 and FIG. 2 show an example in which three-stage rolling of forming rolling, width rolling and thickness rolling is performed. However, depending on the material and dimensions of the steel slab 1, there is a case where the forming rolling is omitted and the two-stage rolling of the width rolling and the thickness rolling is performed. Also in the two-stage rolling, one pass is added to the rolling schedule in which the final pass is completed at the front of the reverse rolling mill in the tentative rolling stage, and rolling is performed.
[0028]
The functions and effects obtained by adding one pass at the tent-rolling stage in the two-stage rolling are the same as those of the one-pass added at the tent-rolling stage in the three-stage rolling described above, and therefore description thereof is omitted.
When the desired surface is the front surface, the “rear surface” may be replaced with the “front surface”.
[0029]
【Example】
A steel slab (215 mm thick) manufactured by the continuous casting method was charged into a reverse rolling mill to manufacture a thick steel plate (13.1 mm thick). At this time, when the rolling schedule was set in accordance with the conventionally applied schedule calculation, a rolling schedule in which the final pass was completed on the front surface of the reverse rolling mill as shown in FIG. 2 was set.
[0030]
Therefore, one pass was added at the stage of the tentering rolling, and the three-stage rolling as shown in FIG. 1 was performed, and the thick rolling was completed on the rear surface of the reverse rolling mill. This is an invention example.
Table 1 shows the plate thickness (mm) after each pass, the required time (seconds) of each pass, and the required time (seconds) between passes in the example of the invention shown in FIG.
[0031]
[Table 1]

[0032]
As shown in Table 1, a steel slab 1 (with a thickness of 215 mm) manufactured by a continuous casting method was charged into a reverse rolling mill in parallel with a longitudinal direction (that is, a casting direction), and a plate thickness was 199.6 mm in a first pass. And The time required for the first pass was 2.2 seconds. Next, the interval between the rolling rolls was adjusted (required time: 5.3 seconds), and a second pass was performed, so that the plate thickness was set to 184.2 mm. The time required for the second pass was 2.6 seconds. These first and second passes are forming rolling.
[0033]
After the forming and rolling (ie, after the completion of the second pass), the interval between the rolling rolls is adjusted, and the rolled material 2 is rotated by 90 ° and charged into a reverse rolling mill in a direction perpendicular to the longitudinal direction. And a third pass. The time required between the second pass and the third pass was 14.9 seconds. The thickness after the third pass was 183.1 mm, and the time required for the third pass was 1.1 seconds. In Table 1, the third to seventh passes are tent-rolling.
[0034]
Since the data after the fourth pass in Table 1 shows data in the same manner as described above, detailed description will be omitted.
After the end of the tent rolling (that is, after the end of the seventh pass), the interval between the rolling rolls is adjusted, and the rolled material 2 is again rotated by 90 ° and charged into a reverse rolling mill in parallel with the longitudinal direction. An eighth pass was performed. The time required between the seventh pass and the eighth pass was 13.5 seconds. The plate thickness after the completion of the eighth pass was 95.4 mm, and the time required for the eighth pass was 2.2 seconds. In Table 1, the 8th to 15th passes are thick rolling.
[0035]
Thus, in the invention example, when the fifteenth pass was completed, the thick steel plate 3 finished to a thickness of 13.1 mm was discharged to the rear surface of the reverse rolling mill. The time required for this reverse rolling was 127.4 seconds as shown in Table 1.
On the other hand, as Comparative Example 1, a steel slab (215 mm thick) manufactured by a continuous casting method was charged into a reverse rolling mill, and three-stage rolling was performed as shown in FIG. 2 to obtain a thick steel plate (13.1 mm thick). ) Manufactured. At this time, a rolling reduction schedule was set in accordance with a conventionally applied schedule calculation, and the thick rolling was completed at the front of the reverse rolling mill.
[0036]
Table 2 shows the plate thickness (mm) after each pass, the required time (sec) of each pass, and the required time (sec) between passes in Comparative Example 1 shown in FIG.
[0037]
[Table 2]

[0038]
The plate thickness after the pass shown in Table 2, the time required for the pass, and the time required between passes are shown in the same manner as in Table 1, and thus detailed description is omitted.
In Table 2, the first and second passes are forming rolling, the third to sixth passes are tent rolling, and the seventh to 14th passes are thick rolling.
When the fourteenth pass was completed in Comparative Example 1 in this way, the thick steel plate 3 finished to a thickness of 13.1 mm was discharged to the front of the reverse rolling mill. Therefore, after the end of the fourteenth pass, a dummy pass was added to discharge the thick steel plate 3 to the rear surface of the reverse rolling mill. The time required for this rolling was 128.9 seconds in total including the dummy pass, as shown in Table 2.
[0039]
Further, as Comparative Example 2, a steel slab (thickness: 215 mm 2) manufactured by a continuous casting method was charged into a reverse rolling mill, and three-stage rolling was performed as shown in FIG. ) Manufactured. The rolling schedule of FIG. 3 is obtained by adding one pass at the stage of the thickening rolling to the thickening schedule of FIG. 2 and finishing the thickening rolling at the rear surface of the reverse rolling mill.
[0040]
Table 3 shows the plate thickness (mm) after completion of each pass, the required time (seconds) of each pass, and the required time (seconds) between passes in Comparative Example 2 shown in FIG.
[0041]
[Table 3]

[0042]
The sheet thickness after the end of the pass, the time required for the pass, and the time required between passes shown in Table 3 are shown in the same manner as in Table 1, and thus detailed description is omitted.
In Table 3, the first and second passes are forming rolling, the third to sixth passes are tent rolling, and the seventh to fifteenth passes are thick rolling.
Thus, in the invention example, when the fifteenth pass was completed, the thick steel plate 3 finished to a thickness of 13.1 mm was discharged to the rear surface of the reverse rolling mill. The time required for this reverse rolling was 130.3 seconds as shown in Table 3.
[0043]
When the time required for the reverse rolling was compared between the invention example and the comparative examples 1 and 2, the invention example was 127.4 seconds, whereas the comparative examples 1 and 2 were 128.9 to 130.3 seconds. there were. Therefore, it has been confirmed that by applying the present invention, the final pass can always be completed at the rear surface of the reverse rolling mill, and the time required to produce a thick steel plate from a steel slab can be reduced.
[0044]
【The invention's effect】
According to the present invention, the final pass can always be completed on a desired surface of the reverse rolling mill. In particular, when the final pass is completed on the rear surface, the time required for manufacturing a thick steel plate from a steel slab can be reduced. As a result, a reduction in the operation rate of the reverse rolling mill can be suppressed, and a reduction in the productivity of the thick steel plate can be suppressed. Can be achieved.
[Brief description of the drawings]
FIG. 1 is a diagram schematically illustrating an example of a rolling schedule according to the present invention.
FIG. 2 is a diagram schematically illustrating an example of a conventional rolling schedule.
FIG. 3 is a diagram schematically showing another example of a rolling schedule.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Steel slab 2 Rolled material 3 Steel plate

Claims (2)

In a rolling method for producing a thick steel plate by performing a three-stage rolling of forming rolling, tent rolling and bulging rolling, or a two-stage rolling of tent rolling and bulging rolling using a reverse rolling mill, If the rolling schedule in which the thickening rolling is finished on the desired surface is set, rolling is performed according to the set rolling schedule, and the rolling schedule in which the thickening rolling is finished on the undesired surface of the reverse rolling mill is set. A method of rolling a thick steel plate, wherein the thick rolling is completed on a desired surface of the reverse rolling mill by adding one pass at the stage of the width rolling. 2. The method according to claim 1, wherein the desired surface is a rear surface of the reverse rolling mill and has a good thickness accuracy.

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