JPH11114603A - Reverse rolling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the efficiency of rolling by shortening the total non-rolling time at the time of automatically executing reciprocating rolling of plural passes to the rough rolled stock for wide flange shape using a reversing mill which is composed by combining a rough universal mill with an edger mill. SOLUTION: In a reverse rolling method in which the reciprocating rolling of the plural passes is executed to a rolled stock 15 by automatically repeating rolling, passing through the mill, stopping, starting and biting with the mill after completing mill-setting change in order using the reversing mill 10, the necessary time for changing mill setting and the length of the rolled stock 15 which are changed by the pass schedule of the rolled stock 15 are determined at every pass and, based on the obtained necessary time for changing the mill setting and length of the rolled stock 15, the acceleration/deceleration time or stopping time of the rolled stock 15 from passing through the mill till biting with the mill are controlled at every pass with a control controller 24 so that the total non-rolling time is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse rolling method for automatically performing reciprocating rolling in a plurality of passes on a rolled material, and for example, performing reciprocating rolling in a plurality of passes on a rough rolled H-beam using a reversing mill. The present invention relates to a reverse rolling method capable of shortening a non-rolling time and improving a rolling efficiency when automatically performing the rolling.

[0002]

2. Description of the Related Art FIG. 15 schematically shows an automatic intermediate rolling process of an H-section steel using a reversing mill constituted by a coarse universal mill 1 and an edger mill 2.

[0003] In this intermediate rolling step, starting, mill biting, acceleration, rolling speed maintenance,
Deceleration, mill removal and stop, standby during mill setting change, and startup (reverse rolling) after mill setting change are performed in order, and the following steps are repeated to perform reciprocating rolling in a plurality of passes, and Is rolled into an H-section intermediate rolled material having the following dimensions. In this specification,
The rolled material after the rough rolling is called an H-beam rough rolled material, and the rolled material after both the rough rolling and the intermediate rolling is called an H-beam intermediate rolled material.

FIGS. 16 to 19 are explanatory views showing an example of the above-described mill setting change. FIG. 16 is a longitudinal sectional view of the coarse universal mill 1.

[0005] The change of the mill setting is, as shown in FIG.
When performing, for example, 19 passes of reverse rolling on the roughly rolled steel 5, in the case of the vertical rolls 3 a and 3 b of the rough universal mill 1, the roll gap is divided into 1 to 19 times and the first pass:
a ₁ (mm), 2nd pass: a ₂ (mm), ..., 19th pass: a ₁₉ (m
m) means that a pass schedule that gradually narrows is set in advance, and the roll gap between the vertical rolls 3a and 3b is changed based on this pass schedule. The roll gap is similarly changed for the horizontal rolls 4a and 4b.

FIGS. 17 (a) to 17 (d) are front views showing the horizontal rolls 4a and 4b of the rough universal mill 1 and the horizontal rolls 6a and 6b of the edger mill 2 with the mill setting changed over time. 18 (a) to 18 (c) are perspective views showing the vertical rolls 3a and 3b of the coarse universal mill 1 in which the mill setting is changed over time. With reference to these drawings, the situation of the mill setting change will be described with time.

As shown in FIGS. 17 (a) and 17 (b), the horizontal rolls 4a, 4b and the horizontal rolls 6a, 6b, which are rotationally driven by the respective drive mechanisms M, M, have a predetermined roll gap. The rolled H-section steel 5 is rolled, and the rolled H-section steel 5 is stopped after passing through the edger mill 2 as shown in FIG. 17 (c). The roll gap between the horizontal rolls 6a and 6b is narrowed by the rolling mechanism M based on the pass schedule, and biting and reverse rolling are performed as shown in FIG. 17 (d).

On the other hand, as shown in FIG.
The vertical rolls 3a and 3b, which are driven to rotate, roll the H-shaped steel rough rolled material 5 with a predetermined roll gap,
After the rolled H-section steel rolled material 5 has passed through the rough universal mill 1 as shown in FIG. 18 (b), the roll gaps between the vertical rolls 3a and 3b are reduced based on the pass schedule. Biting and reverse rolling are performed as shown in FIG. 18 (c).

In the mill setting change, not only the roll gaps of the rough universal mill 1 and the edger mill 2 are changed, but also the gaps between the web guides and side guides for appropriately guiding the H-shaped steel rough rolled material 5 to the rolling rolls. Changes are also made. FIGS. 19A and 19B are explanatory views of the coarse universal mill 1 and the edger mill 2 both showing the web guide 7 and the side guide 8, and FIG. 19A is a front view and FIG. 19B is a top view.

As shown in FIG. 1, in the mill setting change, the horizontal rolls 4a, 4b and the vertical rolls 3a, 3b of the coarse universal mill 1 and the horizontal rolls 6a, 6b of the edger mill 2 are respectively set according to the pass schedule. And the gap between the web guide 7 and the side guide 8 is also narrowed.

However, in a normal rolling mill, the time required to change the roll gap between the rolling rolls is longer than the time required to change the gap between the web guide 7 and the side guide 8. Therefore, the time required for changing the mill settings is governed by the amount of change in the roll gap, the moving speed of each roll, etc.
There are lengths depending on the pass schedule. In the case of a normal reversing mill, the time required to change the mill settings is
The shortest was 1.5 seconds and the longest was 5.0 seconds.

In FIG. 16, the biting by reverse rolling must be performed after the mill setting change is completed in order to ensure proper biting of the rolled material. Also, a predetermined time is required for deceleration after the mill is removed, acceleration after startup, and the like.

[0013] Therefore, the non-rolling time from the mill removal of the rolled material to the biting of the mill in the reverse rolling (in the present specification, this is referred to as “reverse time”, and the sum of the reverse times in each pass is referred to as “total non-rolling time”). ) Is determined as the sum of the time required for accelerating and decelerating the rolled material (referred to as “acceleration / deceleration time” in this specification) and the stop time, and the time required for changing mill settings (this specification). In the above, it is referred to as "time required for mill setting change.") Conventionally, in consideration of safety, a fixed value (for example, 6.7 seconds) longer than the maximum time required for mill setting change was used regardless of the pass schedule.

[0014]

However, according to such a conventional reverse rolling method, the total non-rolling time cannot be reduced because the reverse time, which is not the time for directly rolling, cannot be reduced. Therefore, the rolling efficiency of the reversing mill had to be reduced.

That is, since the reverse time is set to a fixed value irrelevant to the pass schedule, in the pass in which the time required for changing the mill setting is short, the stop time of the H-shaped steel roughly rolled material is increased by that amount. This contributed to increasing the reverse time.

Further, the acceleration / deceleration of the rough-rolled H-section steel increases as the rolled material length increases with the progress of the pass schedule.
Since the number of table rollers with which the rough-rolled material comes into contact increases, the size becomes large. Therefore, although the acceleration / deceleration time of the H-shaped steel roughly rolled material naturally decreases with the progress of the pass schedule, since the reverse time is a fixed value, the reverse time is also increased from this point.

For this reason, the reverse time cannot be reduced by the sum of the excess of the acceleration / deceleration time and the stop time generated in each pass, which is a main cause of lowering the rolling efficiency of the reversing mill. .

Here, an object of the present invention is to provide a reversing
It is an object of the present invention to provide a reverse rolling method capable of improving the rolling efficiency of a mill. More specifically, for example, an H-section steel is formed by using a reversing mill composed of a combination of a coarse universal mill and an edger mill. An object of the present invention is to provide a reverse rolling method capable of shortening a total non-rolling time and improving a rolling efficiency when automatically performing reciprocating rolling in a plurality of passes on a rough rolled material.

[0019]

Means for Solving the Problems The inventors of the present invention intend to achieve the above object by shortening the above-mentioned reverse time to the minimum, and as a result of intensive studies, the following findings are listed. The findings were obtained, and the present invention was completed based on these findings.

Normally, reverse rolling is performed according to a pass schedule in which the rolling reduction is gradually reduced, but the time required for changing the mill settings gradually decreases due to the progress of such a pass schedule. The required mill setting change time can be obtained for each pass as a calculated value based on a pass schedule or a table value based on actual measurement before rolling is started.

As the sheet thickness decreases due to the progress of the pass schedule, the length of the rough rolled H-section steel gradually increases. As the length of the rolled material increases, the number of table rollers that come into contact with the roughly-rolled H-beam increases, and the total resistance or driving force received from all the table rollers with which the roughly-rolled H-beam contacts increases. The deceleration after disengagement and the acceleration to the required biting speed increase. The rolled material length can also be obtained for each pass as a calculated value based on a pass schedule or a table value based on actual measurement before rolling is started.

As described above, the reverse time is determined as the sum of the acceleration / deceleration time and the stop time of the rough rolled H-section steel so as to be longer than the time required for the mill setting change.
Therefore, these times are accurately obtained for each pass, and the acceleration / deceleration time in each pass and further the stop time are appropriately determined based on the required mill setting change time and the rolled material length obtained for each pass. As a result, the reverse time for each pass can be shortened, and preferably minimized. As a result, the total sum of the reverse times in each pass can be reduced or minimized, and the rolling efficiency of the entire reversing mill can be improved.

In the above-mentioned section, when the H-section rough rolled material is bitten into the rough universal mill after the mill is removed, the H-section rough rolled material is taken into consideration in consideration of shortening the reverse time and maintaining a predetermined biting speed. Control the acceleration / deceleration time of the material,
In the case where the H-section rough rolled material bites into the edger mill after leaving the mill, priority is given to shortening the reverse time, and the stop time of the H-section rough rolled material is controlled. -Desirable for improving the rolling efficiency of the entire mill.

Here, the gist of the present invention is to use a reversing mill to automatically and repeatedly repeat milling, mill removal, stoppage, start-up, and mill biting after completion of mill setting change. In the reverse rolling method in which reciprocating rolling of multiple passes is performed, the required mill setting change time and the length of the rolled material that change according to the pass schedule of the rolled material are obtained for each pass, and the calculated required mill setting change time and the rolled material length are obtained. So that the total non-rolling time is reduced,
For each pass, one or both of the acceleration / deceleration time and the stop time of the rolled material from the mill removal to the mill biting are controlled.

In the above-described reverse rolling method according to the present invention, the time required for changing the mill setting is obtained by calculation based on the pass schedule, and the length of the rolled material is obtained by actual measurement, thereby improving control accuracy and simplifying control. It is desirable from the viewpoint of chemical conversion.

In the reverse rolling method according to the present invention, when the mill biting is performed on the coarse universal mill, the acceleration / deceleration time is preferentially controlled to set the predetermined biting speed in the pass. When the mill biting is performed on the edger mill, the stop time is controlled preferentially to reduce the non-rolling time in the pass. It is desirable to improve the rolling efficiency.

Further, in the above-mentioned reverse rolling method according to the present invention, the mill setting change may be a vertical roll reduction setting change for a coarse universal mill, and a horizontal roll opening setting change may be performed for an edger mill. It is desirable to minimize the reverse time.

For example, when performing the reverse rolling method according to the present invention, first, a pass schedule is determined from dimensions of a rolled material before and after rolling, and a time required for mill setting change is calculated for each pass based on the pass schedule. And
Based on the calculated mill setting change required time for each pass and the rolled material length measured for each pass, as the reverse time in each pass is reduced, depending on the type of mill to be engaged, One or both of the acceleration / deceleration time and the stop time of the rolled material until the biting of the mill is controlled.

In the present invention, for example, the reversing mill is composed of one coarse universal mill ( _one U1 mill) or one edger mill and two coarse universal mills.
In the case of a combination with a base (U ₁ mill-E mill-U ₂ mil tandem arrangement), that is, when the rolled material that has passed through the mill is the coarse universal mill, the specified bite So that you can maintain speed
The acceleration / deceleration time of the rolled material is controlled with priority.

On the other hand, the reversing mill is a combination of one edger mill and one coarse universal mill (U ₁ mill-
(E tandem arrangement of the E-mill), that is, when the rolled material that has passed through the mill is the next universal mill that is a coarse universal mill, the rolled material is maintained in the same manner as described above so that the predetermined biting speed can be maintained. Is controlled preferentially, and when the rolled material that has passed through the mill is the next biting mill to be an edger mill, the stopped time of the rolled material is preferentially controlled so that the reverse time is reduced as much as possible.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the reverse rolling method according to the present invention will be described in detail with reference to the accompanying drawings. In the following description of the embodiment, it is assumed that the reversing mill includes one coarse universal mill and one edger mill.
The case where intermediate rolling is performed on a rough rolled H-section steel material is performed as an example.

FIG. 1 is an explanatory view schematically showing an example of a reversing mill automatic rolling step 10 constituted by a rough universal mill 11 and an edger mill 12.

In the reversing mill automatic rolling step 10 used in the present embodiment, a coarse universal mill 11 having horizontal rolls 14a, 14b and vertical rolls 13a, 13b, in which the roll gap can be changed, and a roll gap can be changed, And an edger mill 12 having horizontal rolls 16a and 16b are arranged in tandem to automatically perform reciprocating rolling in a plurality of passes on a rough rolled material 15 of an H-section steel.

The horizontal rolls 14a and 14b are connected to the first main motor 17
, And the vertical rolls 13 a and 13 b are driven by a vertical roll pressure reduction motor 18. Vertical roll reduction motor 18
Is connected to a PLG 18 'to detect the vertical roll reduction position and output it to the control controller 24 described later.

The horizontal rolls 16a and 16b are connected to the second main motor 19
, And connected to the second main motor 19
The rolled material length is measured by the controller 24
Is output to

The horizontal rolls 16a and 16b
The amount of reduction is adjusted by the reduction mechanism 22 driven by. The PLG 23 is connected to the horizontal reduction motor 21, and the horizontal roll opening is detected and output to the controller 24.

The detected value of the vertical roll reduction position from the PLG 18 ', the detected value of the rolled material length from the PLG 20, and the detected value of the horizontal roll opening from the PLG 23 are input to the controller 24. Automatic reversing mill rolling process
From the process computer 25 which performs the management of 10, the entire pass schedule determined by calculation from the sheet thickness before and after rolling is input.

The controller 24 performs control processing to minimize the reverse time by performing arithmetic processing and outputting the contents listed in (i) to (vi) based on these input data.

[0039] (i) from the detected value and the total pass schedule of the vertical roll pressing position, the vertical roll rolling set amount X _V of crude universal mill 11 calculates for each path.

[0040] (ii) based on the vertical roll rolling set amount X _V of each pass of the computation crude universal mill 11, as well as calculate the stop distance L ₂ of each pass, the vertical roll rolling set X of each pass _V is output to the vertical roll reduction drive device 18a, and the drive control of the vertical roll reduction motor 18 is performed for each pass.

Here, the stopping distance L ₂ indicates the minimum distance of each pass in which the H-shaped steel rough rolled material 15 at the time of biting can secure a predetermined biting speed. It is governed by the length of the rolled material 15, the acceleration / deceleration force of the table roller 26 described later, and the biting speed.

The (iii) The from the detected value S of the strip length, to calculate the stop distance L ₁ of each pass. Here, the stopping distance L ₁ indicates the minimum distance mill exit the H-shaped steel rough rolled material 15 may be stopped for each path, the length of the H-shaped steel rough rolled material 15, a table roller 26 to be described later Acceleration and deceleration forces and the speed at the time of mill removal.

[0043] From the (iv) a horizontal roll detection value for the opening and the total pass schedule, a horizontal roll opening setting amount X _H of Ejjamiru 12, as well as operation for each path, and outputs to the horizontal roll drive device 21a, The drive control of the horizontal reduction motor 21 is performed for each pass.

[0044] (v) calculating the stopping time T for each path from the horizontal roll opening setting amount X _H of the calculated Ejjamiru 12.

(Vi) From the calculated stop distance L ₁ , stop distance L ₂ and stop time T for each path and the total path schedule,
For each pass, the rolling speed, stopping distance (acceleration / deceleration time) and stopping time are calculated, and these are calculated by the first mill drive device 17.
a, the second mill drive device 19a, and further output to the table roller 26 that is installed on each of the upstream side and the downstream side of the reversing mill automatic rolling process 10 and drives the H-section steel rough rolled material 15, The drive control of the first main motor 17 and the second main motor 19 is performed, and the table rollers 26 are controlled.
Is performed. The first main motor 17, the second main motor 19 and the table roller 26 are controlled synchronously.

[0046] Specifically, the rolling speed is determined for each path based on the total pass schedule, the stopping distance (acceleration and deceleration time), the same value as the larger value among the stop distance L ₁ and stop distance L ₂ Is determined for the next pass before biting into the coarse universal mill, and the stop time is the stop time
Based on T, it is determined for the next pass before biting into the edger mill.

FIG. 2 shows an edger mill 12 in the reversing mill automatic rolling step 10 of this embodiment shown in FIG.
When the H-shaped steel rough rolled material 15 passes from the coarse universal mill 11 to the rough universal mill 11 (U1 side) and when the H-shaped steel rough rolled material 15 passes from the coarse universal mill 11 to the edger mill 12 (E side)
FIG. 4 is an explanatory diagram showing the contents of control by the controller 24 for (1) and (2). The control controller 24 controls the following contents for the U1 side and the E side.

(U1 side) (1) Rough universal mill based on all pass schedule
Capturing vertical roll rolling set amount X _V of 11 for each path. (2) From the vertical roll reduction amount X _V for each pass, the vertical roll reduction setting change required time T ₁ is set for each pass, T ₁ = a X _V
+ B (where a and b are constants).

(3) The acceleration time before the mill bites into the mill and the deceleration time after the mill leaves the mill are related to the length of the rolled material as illustrated in the graph of FIG. measured value
Based on S, the acceleration / deceleration time Ta is determined for each pass as Ta = γ ₂ / S.

(4) The stopping distance L _{2 for} each pass at which the H-shaped steel roughly-rolled material 15 can maintain a predetermined biting speed is represented by a vertical roll reduction set amount X _V and a graph in FIG. since in the exemplified relationship, the stop distance L ₂ in each pass, L ₂
= (CX _V + d) / 2 (where c and d are constants).

[0051] (5) based on the acceleration and deceleration time Ta calculated for each path and stop distance L _2, the acceleration and deceleration and stop times can be shortened reverse time can be ensured the biting speed required for each path After the determination, the drive control of the first main unit motor 17, the second main unit motor 19, and the table roller 26 is performed.

[0052] (E side) (1) based on the total pass schedule, taking a horizontal roll opening setting amount X _H of Ejjamiru 12 in each pass. (2) from the horizontal roll opening setting amount X _H of each pass, to calculate the horizontal roll set sorting time required for each path.

[0053] (3) mils stop time after omission, horizontal roll set for each pass because it is proportional to the horizontal roll opening setting amount X _H of Ejjamiru 12, calculated as illustrated graphically in FIG. 2 from the amount X _H, it calculates the stop time T after the H-shaped steel rough rolled material 15 has passed through the Ejjamiru 12 for each path.

(4) Based on the acceleration / deceleration time and the stop time calculated for each pass, the acceleration / deceleration time and the stop time that can reduce the reverse time are determined for each pass.
7. The drive control of the second main motor 19 and the table roller 26 is performed.

[0055] Incidentally, as exemplified by the three graphs in FIG. 2, the rolled material length S - acceleration and deceleration time Ta, the vertical roll rolling set amount X _V - stop distance L _2, and the horizontal roll opening setting amount X _H - For the basis for deriving the relationship of the downtime T,
It will be described later.

As described above, in the case where the mill to be meshed next is the coarse universal mill 11, the H-shaped steel rough rolled material 15 after the mill is removed by the controller 24 at an appropriate meshing speed. The drive of the first main motor 17, the second main motor 19, and the table roller 26 is controlled so as to be able to be engaged with the roller. When the next mill to be engaged is the edger mill 12, the reverse time is reduced. The drive control of the first main unit motor 17, the second main unit motor 19, and the table roller 26 is performed so as to be able to be performed.

In other words, the coarse universal mill 11 performs a large rolling reduction by setting a large amount of change in the roll gap as compared with the edger mill 12, so that the biting torque increases, so that the biting speed is surely increased. It is important to secure stable rolling. In particular, in the initial pass, since the length of the H-section steel rough rolled material 15 is short, the weight (unit weight) per table roller after passing through the coarse universal mill 11 is large, and the acceleration distance and the deceleration distance are small. long. Therefore, the acceleration / deceleration time must be set so that a sufficient acceleration distance is secured and the necessary biting speed is maintained.
(Acceleration / deceleration).

On the other hand, as compared with the coarse universal mill 11, the edger mill 12 has a smaller rolling load and a smaller amount of change in the roll gap because it uses a grooved roll to reduce the pressure at the tip of the flange, for example. Therefore, since the biting torque is reduced and the biting speed is also low, it is easy to secure the biting speed. Therefore, the stop time is controlled so that the reverse time can be reduced as much as possible.

In the present embodiment, the mill setting change of the coarse universal mill 11 is only the vertical roll reduction setting. However, among other items requiring setting change, the setting change is required from the viewpoint of stable operation. This is because the time required for setting the vertical roll reduction that must be completed is the longest. For example, for a web guide that does not directly contact the rough-rolled material 15 such as a web guide, the setting change is slightly delayed and the H-shape There is no problem even if it does not catch up with the milling of the rough rolled material 15,
This is because the reverse time can be shortened accordingly. For the same reason, the mill setting of the edger mill 12 is changed only to the horizontal roll opening.

As described above, according to the present embodiment, when the reversing mill 10 composed of the rough universal mill 11 and the edger mill 12 is used to perform the reverse rolling on the H-shaped steel roughly rolled material 15 a plurality of times. The controller 24
The mill setting change time is calculated for each pass based on the pass schedule, and based on the mill setting change time and the rolled material length actually measured at each pass, the mill removal time is reduced so that the reverse time is reduced. Rolled H-section steel after rolling
In order to control both the acceleration / deceleration time and the stop time of the H-shaped steel roughly rolled material 15 between the mill removal and the mill biting for each pass, the reverse time is minimized while performing stable rolling. Can be suppressed.

[0061]

Next, the reverse rolling method according to the present invention will be described in more detail with reference to the accompanying drawings and practical data.

FIG. 3 is an explanatory view schematically showing a reversing mill automatic rolling step 10 constituted by the coarse universal mill 11 and the edger mill 12 used in the present embodiment, and FIG.・ Mill automatic rolling process
FIG. 9 is a flowchart showing control contents of ten control controllers 24. This reversing mill automatic rolling process
10 is a reversing mill automatic rolling process 10 shown in FIGS.
Therefore, the same components are denoted by the same reference numerals in the drawings, and redundant description will be appropriately omitted. In the description of the present embodiment, the coarse universal mill 11
The rolling in which the H-shaped steel rough rolled material 15 travels from the to the edger mill 12 is referred to as an “odd pass”, and the reverse is referred to as an “even pass”.

[S10] In S10, H input from S140
A rough universal mill is activated by a stop signal for
11, the table start of the edger mill 12 is detected, and S20
Output to

[S20] At S20, the bite of the H-section steel rolled material 15 into each mill is detected and output to S21 and S30.

[S21-S23] Here, in S21, the start of measurement of the length S of the rough-rolled material 15 of the H-section steel is detected by the bite signal in S20, and the completion of measurement is detected in S22.
23 based on the length of the H-shaped steel rough rolled material 15 determined by the calculated stop distance L _1, is output to S26. Explaining this calculation of stopping distances L ₁ below.

(Calculation of Stop Distance L ₁ ) FIG. 5 is a diagram showing a rough rolled H-section steel roll by a table roller 30 driven by a drive unit 31.
FIG. 15 is an explanatory diagram showing a situation where 15 is conveyed. The H-section roughly rolled material 15 has a large total weight (unit weight) per table roller 30 during the initial pass, as shown by the solid line in FIG. However, as the path progresses, the unit weight of the table roller 30 gradually decreases because the total length increases, and the acceleration and deceleration of the H-shaped steel roughly rolled material 15 increase. Here, the acceleration / deceleration time of the H-section steel rough rolled material 15
Ta (seconds) is the GD ² of H-shaped steel rough rolled material 15 obtained by the following equation (1) changes.

[0067]

[Equation 1] Ta = ｛(GD _S ² + GD _A ² ) × N ² × 10 ^-3 )｝ / (365P) ・ ・ ・ ・ ・ (1) where G _S ² : GD of rough rolled H-section steel ^{2 (kg-m 2) GD} a 2: ^{motor, GD 2 (kg-m 2} ) of the table rollers and the like N: rotational speed (rpm) P: motor capacity (KW), where the H-shaped steel rough rolled material 15 GD ² is determined by weight, which is determined by length. Material weight W (kg)
Is determined by the type of steel, the unit weight W ₁ (kg / m) is calculated by measuring the length S of the rolled material on the edger mill 12 side in all passes.

[0068]

[Equation 2] W ₁ = W / S (kg / m) ... (2) where W is the material weight (kg) and S is the rolled material length (m)
It is.

The reason for measuring the length of the H-shaped steel roughly-rolled material 15 on the side of the edger mill 12 in the previous pass is to prevent a control delay due to the measurement of the current pass, and to measure the length of the current pass from the previous pass. This is because the H-section steel rough-rolled material 15 does not become short. From the unit weight W ₁ (kg / m) determined by the equation (2), the GD ² of the roughly rolled H-section steel 15 is determined by the following equation (3).

[0070]

GD _S ² = 365 × W ₁ × (V _K / n) ² (kg−m ² ) (3) where V _K is the biting speed (m / s) and n Indicates the number of rotations (rpm) of the table roller. By substituting equation (2) into equation (3), equation (4) is obtained.

[0071]

GD _S ² = 365 × W × (V _K / n) ² / S (kg−m ² ) (4) where the biting speed (V _K / n) ² is constant By simplifying equation (4), the following equation (5) is obtained.

[0072]

GD _S ² = γ ₁ / S (kg−m ² ) (5) Therefore, the acceleration / deceleration time Ta (second) of the rough rolled material 15 is
The relationship with the length S (m) of the roughly-rolled H-section steel 15 is approximated by the following equation (6).

[0073]

## EQU6 ## Ta = γ ₂ / S (second) (6) FIG. 6 shows the rolled material acceleration / deceleration time Ta expressed by the equation (6).
6 is a graph showing a relationship between the length of a rolled material and the length S of the rolled material.

[0074] For example, in (1) and (3), the slab weight, motor output, motor rotation speed, by substituting the table roller rotational speed or the like, GD _S ^2, Ta is obtained for each path, (6) The equation is specified specifically.

As shown in the graph of FIG. 6, the acceleration / deceleration time Ta (second) of the rough-rolled H-beam 15
If the control is performed between the maximum unit weight acceleration / deceleration time according to S (m) and the minimum unit weight acceleration / deceleration time, the standby time can be made zero.

Here, the stopping distance L ₁ (m) is L ₁ = V _K × Ta
/ 2 (m), substituting this equation into equation (6) gives L ₁ = V _K × γ ₂ / S / 2 (m), and the biting speed V _K (m
/ s) is constant, the stopping distance L ₁ (m) and the rolled material length S (m)
Is given by the following equation (7).

[0077]

Equation 7] _{L 1 = γ 3 / S /} 2 (m) ····· (7) 7, the (7) and the rolled material stop distance L ₁ represented by formula rolled material and length S 6 is a graph showing the relationship of.

[S24-S25] In S24, the time required to change the vertical roll reduction is calculated.
Is calculated stop distance L ₂ at 25, is output to S26. Less than,
The vertical roll rolling set replacement requires time and calculation of stopping distances L _2, it will be described.

(Calculation of vertical roll reduction setting change required time)
The opening amount setting under the vertical roll pressure is, for example, 60 mm → 30 mm in one pass to the next pass, and the set amount is 30 mm. Increase the opening of the coarse universal mill 11 under vertical roll pressure by 30.
If you try to change the mm, due to characteristics such as mill responsiveness,
The rolling speed changes stepwise as acceleration α, maximum speed v, deceleration β ₁ , deceleration β ₂ , deceleration β ₃ . FIG. 8 is a graph showing the vertical roll reduction speed over time when the opening degree of the vertical roll reduction of the coarse universal mill 11 is changed. In the graph shown in FIG. 8, α: acceleration rate (mm / s ² ), β ₁ :
Deceleration rate (mm / s ² ), β ₂ : deceleration rate (mm / s ² ), β ₃ : deceleration rate
(mm / s ^2), maximum speed: v (mm / s), X V: Vertical roll reduction set amount (mm), x _1: distance at the maximum speed operation (mm), deceleration 1, deceleration 2, deceleration 3 Each speed is v ₁ , v ₂ , v ₃ ,
Acceleration, maximum speed, deceleration 1, deceleration 2, the deceleration 3 of the time is _{t 1, t 2, t 3} , t 4, t 5 , respectively, the vertical rolls to completion (stop) from the mill set replacement start (start) The setting change required time T ₁ (second) is given by the following equation (8).

[0080]

T ₁ = t ₁ + t ₂ + t ₃ + t ₄ + t ₅ (8) where t ₁ = v / α, t ₂ = x ₁ / v, t ₃ = v ₁ / β ₁ , T ₄ = v ₂
/ β ₂ , t ₅ = v ₃ / β ₃ . Therefore, the vertical roll reduction amount X _V (mm) and the vertical roll setting change time T ₁
The relationship with (sec) is approximated to a substantially linear relationship by the following equation (9), using a and b as constants.

[0081]

## EQU9 ## T ₁ = a · X _V + b (9) FIG. 9 shows the vertical roll reduction amount X _V expressed by the equation (9) and the required time T _{1 for} changing the vertical roll setting. 6 is a graph showing a relationship with the graph.

As a result, the calculation software of the controller 24 is simplified. Note that the constants a and b may be appropriately set while matching the operating conditions. In a region where the maximum speed is not reached, the setting change time is short and the reverse time is longer than this, so that there is no problem in approximating a straight line by the equation (9).

[0083] (Stop distance calculation L ₂₎ stops in the vertical roll pressure settings replacement time calculated as described above T ₁ (sec) distance L ₂ (mm), i.e. H-beam during inclusive bite rough rolled material 15 There minimum distance L ₂ each pass which can maintain a predetermined biting rate, when the speed biting and V _k (m / s), may be smaller than the actual stopping distance L _1. FIG. 10 is a graph showing such a relationship.The relationship between the vertical roll reduction setting change time T ₁ (second) and the biting speed V _k (m / s) is given by the following equation (10). .

[0084]

Equation 10] _{L 2 = V k × T 1} /2 (m) ····· (10) , where the vertical roll rolling set replacement requires time, because given by equation (9), (10) By substituting equation (9) into equation (11), equation (11) is obtained.

[0085]

L ₂ = V _k × (a · X _V + b) / 2 (m) (11) Here, when this equation (11) is simplified, the rolled material stopping distance L ₂
(mm) and the vertical roll reduction amount V _k (mm)
It is given by equation (12).

[0086]

L ₂ = (c · X _V + d) / 2 (m) (12) where c and d are constants. FIG. 11 is a graph showing this relationship. As a result, the vertical roll reduction amount X _V
It can be calculated stop distance L ₂ on the basis of.

[0087] [S26] Then, in S26, is compared magnitudes of the stopping distance L ₁ and the stop distance L _2, a large value is output.
As a result, it is possible to prevent the stopping distance from being controlled so small that the predetermined biting speed cannot be maintained. Then, a large value is output based on the comparison result in S130 described later.

[S30] At S30, the acceleration of the rough rolled H-section steel 15 and the rolling at the rolling speed so as to reach the calculated acceleration time are detected and output to S40.

[S40] In S40, the deceleration of the rough-rolled H-section steel 15 is detected so as to reach the calculated deceleration time, and is output to S50.

[S50] At S50, it is detected that the rough rolled H-section steel 15 has come off the edger mill 12, and the steps S51 and S51 are performed.
The mill output is output to 60, and the rough rolled H-section steel 15
Deceleration is started.

[S51, S52] Here, in S51, the start of the mill setting change is detected by inputting the mill omission, and the completion of the horizontal roll opening setting change of the edger mill 12 is detected in S52, which will be described later. Is output to S90.

[S60] At S60, the stoppage of the roughly rolled H-section steel 15 is detected and output to S70. Here, in S61, the required time for changing the horizontal roll setting of the edger mill 12 is determined in S62.
Then, the stop time T is calculated as follows.

The required time T ₂ (second) for changing the horizontal roll opening of the edger mill 12 is expressed by X _H (m
m), it is calculated by the following equation (13) in the same manner as the vertical roll reduction.

[0094]

Equation 13] _{T 2 = e X H + f} ( s) ----- (13) where, e, f are constants.

In this embodiment, on the side of the edger mill 12, the stopping distance L ₃ (m), which is the distance at which the H-shaped steel roughly rolled material 15 actually stops, is a constant value.
The time t (second) from when the 15 leaves the edger mill 12 to stop, reverse start, and re-engage is also constant. Therefore, the stop time T (second) may be determined by the following equation (14).

[0096]

T = T ₂ −t (sec) (14) Similarly, by substituting equation (13) into equation (14), equation (15) is obtained.

[0097]

Equation 15] _{T = e X H + f -t} ( s) ...... (15) where, e, f are constants and t is also simplified since it is fixed, stop time T (sec ) And the horizontal roll opening amount X
The relationship with _H (mm) is given by equation (16).

[0098]

Equation 16] T = g X _H -h (s) ...... (16) where, g, h are constants.

[0099] Figure 12 is a graph showing the relationship between the horizontal roll opening setting amount X _H and stop time T by (16). By using the relationship shown in this graph, the optimal stop time
It is possible to determine the rolled material starting timing at which T can be obtained.

FIG. 13 is a graph showing the biting speed of the rolled material, the stopping distance, and the stopping time. Since the stopping distance L ₃ is constant, the reverse time t is also constant, and the horizontal roll opening set amount is set. by determining the stop time T in accordance with the X _H, it is possible to obtain an optimum stop time T.

[S70] Then, the stop time calculated in S62
T is output to S70. At S70, the control of the stop time of the H-section rough rolled material 15 is performed based on the stop time T, and the control is output to S80.

[S80] In S80, the start of the table of the edger mill 12 and the coarse universal mill 11 is detected by the start of the rough rolled material 15 of the H-section steel, and is output to S90.

[S90] In S90, activation of the table in S80 and S
When the horizontal roll opening degree change of the edger mill 12 of 52 is completed, the bite of the H-shaped steel rough rolled material 15 into each mill is detected and output to S100.
Is accelerated.

[S100] In S100, the acceleration of the rough rolled material 15 of the H-section steel, that is, the increase in the rolling speed and the rolling at the rolling speed are detected and output to S110.

[S110] At S110, the deceleration of the H-section steel rolled material 15, that is, the decrease of the rolling speed is detected, and the result is output to S120.

[S120] In S120, it is detected that the rough-rolled H-section material 15 has left the mill from the rough universal mill 11, and the missing mill is output to S130 and S121.

[S121] At S121, the start of the mill setting change is detected by the detection of the mill omission at S120, and the completion of the vertical roll setting change is detected at S122, which is output to S20.

[S130] In S130, the acceleration / deceleration time of the H-shaped steel rough rolled material 15 is controlled so that the stopping distance of the H-shaped steel rough rolled material 15 is optimized based on the comparison result from S26. Is minimized and output to S140.

[S140] In S140, the H-shaped steel roughly rolled material 15 is decelerated and stopped at the deceleration timing in S130, and a stop signal is output to Step 10. Thus, according to the present embodiment, the reverse time can be suppressed to the minimum.

The method of the present invention described in detail above and the conventional method described above (reverse time: fixed at 6.7 seconds) are described in JI.
Thirteen passes of reverse rolling were performed on a roughly rolled H-section steel of SH500 × 200, and the breakdown of each rolling time was compared. The results are shown graphically in FIG.

The reverse time of one pass is 6.7 in the conventional method.
Seconds, whereas the method of the present invention averages about 5.4 seconds.
Reduced for 1.3 seconds. As a result, the total non-rolling time, which is the total of the 13-pass reverse times, could be reduced by about 14 seconds, and the rolling efficiency could be improved. The improvement of the total non-rolling time by the improvement of the conventional method was at most about 1 second in the total of 13 passes, and the reduction of the total non-rolling time by the method of the present invention was such that the conventional method could not achieve it at all. From this fact,
It is clear that the method of the present invention has a remarkable effect over the conventional method.

[0112]

[Modification] In the embodiments and examples described in detail above, the case where the rolled material is a rough rolled H-beam is taken as an example, but the reverse rolling method according to the present invention is not limited to such an embodiment. However, the present invention is equally applicable to a rolled material that is rolled by a reverse rolling method that performs reciprocal rolling in a plurality of passes. As such a rolled material, for example, there is a hot-rolled thick steel plate.

In the embodiment and the examples, the time required for changing the mill setting is obtained by calculation based on the pass schedule, and the length of the rolled material is obtained by actual measurement. However, the reverse rolling method according to the present invention employs this method. The present invention is not limited to such an embodiment, and the mill setting change required time and the rolled material length may be obtained by calculation or actual measurement. In addition, in order to obtain the mill setting change required time by actual measurement, a table value for the same type and the same dimension may be created by actual measurement.

In the present embodiment and examples, the acceleration / deceleration time is controlled when the mill into which the H-shaped steel rough rolled material 15 bites next is a coarse universal mill, and the stop time is controlled when the mill is an edger mill. Was taken as an example,
These may be appropriately combined. For example, when the rough-rolled H-shaped material 15 subsequently bites into the coarse universal mill, the acceleration / deceleration time is controlled. However, if there is still room to reduce the reverse time, the stop time is also controlled. May be shortened.

[0115] Further, in the present embodiments and examples, taken as an example a case constituted reversing mill is the combination (U ₁ tandem arrangement of mill -E mils) of 1 group and the coarse universal mill 1 group Ejjamiru was but reverse rolling method according to the present invention is not limited to such embodiment, the coarse universal mill 1 group (U ₁ mil 1 group located) or in combination with 1 group and coarse universal mill 2 group Ejjamiru (U ₁ Mill-E mill-U ₂ mil tandem arrangement). In this case, since the mill into which the rolled material that has passed through the mill bites next is always a coarse universal mill, the control of the acceleration / deceleration time is performed prior to the control of the stop time.

[0116]

As described above in detail, according to the present invention, it is possible to improve the rolling efficiency of a reversing mill, and more specifically, it is constituted by a combination of a rough universal mill and an edger mill. Reversing
When the reciprocating rolling of the H-section steel rough rolled material was performed a plurality of times using a mill, the non-rolling time was shortened and the rolling efficiency was improved.

That is, according to the present invention, (1) quality improvement by improving product productivity and quality uniformity, (2) drastic reduction of power and cooling water consumption by shortening rolling time, and (3) operation It has become possible to control cost increase by fully automating and (4) only by software modification of the controller. The significance of the present invention having such an effect is extremely remarkable.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing an example of a reversing mill automatic rolling process including a rough universal mill and an edger mill.

FIG. 2 shows a case where a rough rolled H-shaped steel sheet passes from an edger mill to a coarse universal mill in the reversing mill automatic rolling process shown in FIG. 1 (U1 side); It is explanatory drawing which shows the control content by a control controller about the case where a rolled material passes (E side).

FIG. 3 is an explanatory view schematically showing a reversing mill automatic rolling step constituted by a coarse universal mill and an edger mill used in an example.

FIG. 4 is a flowchart showing control contents of a controller in a reversing mill automatic rolling process.

FIG. 5 is an explanatory diagram showing a situation in which a roughly rolled H-section steel is conveyed by a table roller driven by a driving device.

FIG. 6 is a graph showing a relationship between a rolled material acceleration / deceleration time Ta and a rolled material length S.

7 is a graph showing the relationship between a rolled material stop distance L ₁ between the rolled material length S.

FIG. 8 is a graph showing the vertical roll reduction speed V over time when the opening degree of the vertical roll reduction of the coarse universal mill is changed.

[9] and the vertical roll rolling set amount X _V, is a graph showing the relationship between the vertical roll set replacement requires time T _1.

FIG. 10 is a graph showing table speed over time.

FIG. 11: Rolled material stopping distance L ₂ and vertical roll reduction amount X
₆ is a graph showing a relationship with _V.

12 is a graph showing the relationship between the horizontal roll opening setting amount X _H and the stop time T.

FIG. 13 is a graph showing a biting speed of a rolled material, a stopping distance, and a stopping time.

FIG. 14 is a graph showing the results of Examples.

FIG. 15 is an explanatory view schematically showing an automatic intermediate rolling process of an H-section steel using a reversing mill constituted by a coarse universal mill and an edger mill.

FIG. 16 is a longitudinal sectional view of a coarse universal mill.

17 (a) to 17 (d) are front views showing a horizontal roll of a rough universal mill and a horizontal roll of an edger mill in which the mill setting is changed over time.

FIG. 18 (a) to FIG. 18 (c) are perspective views showing a vertical roll of a coarse universal mill in which mill setting is changed over time.

FIGS. 19A and 19B are explanatory views of a coarse universal mill and an edger mill showing both a web guide and a side guide, wherein FIG. 19A is a front view and FIG. 19B is a top view.

[Explanation of symbols]

 10 Reversing mill automatic rolling process 11 Coarse universal mill 12 Edger mill 13a, 13b Vertical roll 14a, 14b Horizontal roll 15 H-section steel rough rolled material 16a, 16b Horizontal roll 17 First main motor 19 Second main motor 24 Control controller 25 Process computer 26 Table roller

Claims (1)

[Claims] 1. A reverse rolling in which a reversing mill is used to automatically and repeatedly repeat rolling, mill removal, stop, start, and mill setting after completion of mill setting in order to perform reciprocating rolling in a plurality of passes on a rolled material. In the method, a mill setting change required time and a rolled material length that vary according to the pass schedule of the rolled material are determined for each pass, and based on the determined mill setting change required time and the rolled material length, total non-rolling is performed. In order to reduce the time, the acceleration / deceleration time and / or the stop time of the rolled material between the mill removal and the mill biting is set for each of the passes,
A reverse rolling method characterized by controlling.