JP3381576B2 - Method and apparatus for preventing meandering of tail end of rolled material in continuous rolling mill - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing meandering occurring at the tail end of a rolled material when the rolled material is continuously rolled by a continuous rolling mill train including a plurality of rolling mills .
And a device, and in particular, when hot-rolling a steel strip by a hot-rolling mill, a method for preventing the meandering that occurs when the tail end of the steel strip to be rolled out is slipped off, and <br / > Regarding equipment.

[0002]

2. Description of the Related Art When a rolled material is continuously rolled by a continuous rolling mill train composed of a plurality of rolling mills, particularly in continuous rolling of a steel strip in a hot finish rolling mill, the tail end of the rolled material is the final rolling. Since the binding force in the width direction is released at the moment of exiting the machine, it becomes easier to meander in one direction.

Depending on the state of the rolled material and the rolling mill, the sharp meandering of the rolled material tail end becomes so large that it collides with the side guide, and the rolled material tail end part is rolled in double or triple folding. A so-called "narrowing" phenomenon occurred when it was bitten into the machine, resulting in problems such as damage to the rolling rolls, deterioration of the surface properties of the product, and deterioration of productivity.

As a method for preventing such a meandering of the rolled material during rolling, generally, a difference load type meandering is used in which the difference between the rolling loads on the operating side and the driving side of the rolling mill is detected and the leveling of the rolling mill is controlled. Control method (hereinafter referred to as prior art 1
In addition, there is known a sensor type meandering control method (hereinafter referred to as prior art 2) in which the sensor detects the meandering behavior of the rolled material on the entrance side of the rolling mill and controls the leveling of the rolling mill.

Further, in Japanese Unexamined Patent Publication No. 62-40928, when a rolling material is continuously rolled by a continuous rolling mill train including a plurality of rolling mills, as shown in FIG. A method of providing a looper 6 and a pinch roll 7 and preventing the meandering by pressing the rolled material 3 with the looper roll 6a attached to the tip of the looper 6 and the pinch roll 7 is disclosed (hereinafter referred to as prior art 3). ing.

Further, Japanese Patent Laid-Open No. 8-10381 discloses that
As shown in FIG. 7, at least three horizontal rolls 1 and 2 are provided on the entrance side of the rolling mill 4, and the rolled material 3 is sandwiched by the horizontal rolls 1 and 2 at at least two locations to prevent meandering. (Hereinafter, referred to as Prior Art 4) is disclosed.

[0007]

The prior arts 1 and 2 have the following problems. (1) In a continuous hot finish rolling mill consisting of multiple rolling mills, the time from when the tail end of the steel strip passes through the rolling mill in the preceding stage of the final rolling mill to when it passes through the final rolling mill is When the plate thickness is 1.6 mm or less, it takes a short time of about 0.5 seconds, and it is impossible to respond to the control signal in such a short time. (2) When the planar shape of the tail end of the rolled material is asymmetric with respect to the width direction of the rolled material, it is not possible to accurately detect the meandering amount. (3) Since the leveling is positively changed, it has a great influence on the stripability of the rolling mill after the stand.

Prior art 3 has the following problems. (1) Since the pinch roll and the rolled material are only in line contact at one place, the restraining force in the width direction of the rolled material is weak,
Meandering cannot be completely prevented. (2) The rigidity for installing the device between rolling mills cannot be increased, and the leveling of the pinch rolls (holding rolls) may change depending on the shape of the trailing edge of the rolled material to promote the meandering of the rolled material. There is.

Prior art 4 has the following problems. (1) In rolling mills other than the final rolling mill, since the rotation of the rolled material on the rolling mill exit side is constrained by the next rolling mill, the meandering prevention effect is large, but the width-direction restraining force on the rolling mill exit side is large. The final rolling mill having a small value has a smaller meandering prevention effect than other rolling mills.

Therefore, an object of the present invention is to solve the above-mentioned problems, and when a rolling material is continuously rolled by a continuous rolling mill train including a plurality of rolling mills, the rolling material tail end is separated from the rolling mill. It is an object of the present invention to provide a method and a device for appropriately preventing the meandering that occurs when the bottom of a part is pulled out.

[0011]

The present invention has been made to solve the above-mentioned problems, and the invention described in claim 1 is a final rolling in a continuous rolling mill train including a plurality of rolling mills. to each of the inlet side and the outlet side of the machine, the roll is provided for clamping the rolled material from above and below, the
The roll consists of at least three horizontal rolls.
Then, use the 3 horizontal rolls to roll the rolled material 2 times.
It is characterized in that it is clamped at more than one place .

According to a second aspect of the present invention, the three horizontal lines are provided.
Of the rolls, at least one horizontal roll barrel length
Is shorter than the width of the rolled material .

The invention according to claim 3 is a plurality of rolling mills.
Of the final rolling mill in the continuous rolling mill train consisting of
The upper and lower rolls on each side
The rolled material from above and below
In the method of preventing the meandering of the tail end, the rolled material is
When passing through the upper and lower rolls of
Is the rolling load on the rolling mills upstream of the final rolling mill.
When the double-cut signal is generated, the upper roll and the front
Move each lower roll in the closing direction to
It is characterized by sandwiching the material.

In the apparatus of the present invention, as described above, the rolls for sandwiching the rolled material from the upper side and the lower side of each of the inlet side and the outlet side of the final rolling mill in the continuous rolling mill train including a plurality of rolling mills. Is provided, and the rolled material is sandwiched by the rolls in at least two places. As a result, the rolled material comes into surface contact with the horizontal rolls at at least two places, and as a result, the restraining force in the width direction of the rolled material is significantly increased. can do.

In the intermediate rolling mill of the continuous rolling mill train, the rotation of the rolled material caused by the asymmetric rolling is constrained by the rolling mills arranged before and after the rolling mill, and the moment generated thereby causes the rolling mill to rotate. An additional rolling direction stress distribution occurs at the roll bite inlet and outlet faces. This additional rolling direction stress distribution acts as a boundary condition and changes the rolling pressure distribution inside the roll bite, resulting in deformation of the rolling mill in a direction that corrects the meandering of the rolled material. Usually, the meandering of the rolled material does not become excessive in the steady part of the rolled material other than the leading end portion and the trailing end portion because the rolling material restraining effect by the front and rear rolling mills is large.

If a meandering prevention device consisting of at least three horizontal rolls for sandwiching the rolled material from above and below is arranged on the entrance side of the rolling mill excluding the final rolling mill, the meandering of the tail end of the rolled material is prevented. can do. However, since the rolled material on the exit side of the final rolling mill is only wound up by the down coiler on the downstream side, there is almost no rolling restraint effect on the rolled material, and the additional rolling direction stress for correcting the meandering described above. No distribution occurs.

Therefore, a meandering preventive device composed of an upper horizontal roll and a lower horizontal roll for sandwiching the rolled material from above and below is arranged on each of the inlet side and the outlet side of the final rolling mill, and the leading end of the rolled material is disposed. When the vehicle passes the anti-meandering device,
Alternatively, when the rolling load cutting signal is generated in the rolling mill upstream from the rolling mill, if the rolled material is clamped by the upper horizontal roll and the lower horizontal roll, the moment required for correcting the meandering in the final rolling mill is also obtained. Can be generated.

If the barrel length of at least one of the upper horizontal roll and the lower horizontal roll of the meandering prevention device is made narrower than the width of the rolled material, when the rolled material is held by the roll, the center of the plate width Since the part is pushed into the horizontal roll to be in a depressed state and the edge part of the horizontal roll is caught in the rolled material, the effect of suppressing the widthwise movement of the rolled material is increased.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a meandering preventing device for a tail end portion of a rolled material in a continuous rolling mill according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic side view showing a first embodiment of the device of the present invention, and FIG. 2 is a schematic plan view thereof. As shown in the drawings, the meandering preventive devices A and A'of the present invention are provided on each of the inlet side and the outlet side of the final rolling mill 4 in the continuous rolling mill train.
Is provided.

The meandering preventive devices A and A ′ sandwich one of the upper horizontal rolls 1 and 1 ′ arranged on the upper surface side of the rolled material 3 and the upper horizontal rolls 1 and 1 ′ so as to sandwich the rolled material 3. Thus, it is composed of two lower horizontal rolls 2 and 2'arranged on the lower surface side thereof. The upper horizontal rolls 1, 1'and the lower horizontal rolls 2, 2'are vertically movable by drive mechanisms 5, 5 ', and the barrel length of each roll is longer than the plate width of the rolled material 3. . The upper horizontal rolls 1, 1'and the lower horizontal rolls 2, 2'may be driven or not driven. Reference numeral 6 denotes a load cell attached to the upper horizontal rolls 1 and 1 ', which is effective when changing the setting of the pressing force.

Next, the operation of the device of the present invention will be described. The leading end of the rolled material 3 may be warped or warped, and in order to prevent the meandering prevention device from being damaged by this, the leading end of the rolled material 3 is provided on the exit side meandering prevention device. Before passing through A ′, the upper horizontal rolls 1 and 1 ′ and the lower horizontal rolls 2 and 2 ′ are retracted from the rolled material 3 by being opened and closed with respect to the rolled material 3.

The leading end of the rolled material 3 has an exit side meandering prevention device A '.
When the rolling load is cut off or when a rolling load cutting signal is generated in the rolling mill upstream of the rolling mill 4, the driving mechanism 5, 5 ′ is used to drive the upper horizontal rolls 1, 1 ′ and the lower horizontal rolls 2, 2 ′. ′ Are moved in the closing direction.
As a result, the rolled material 3 comes into surface contact with the upper horizontal rolls 1 and 1'and the lower horizontal rolls 2 and 2'at two places, and the restraining force in the width direction of the rolled material remarkably increases. The meandering of the ends is properly prevented.

Further, by sandwiching the rolled material 3 by the meandering preventive devices A and A'arranged on the inlet side and the outlet side of the rolling mill 4, respectively, an additional rolling direction stress can be generated, As a result, it is possible to prevent the meandering of the tail end portion of the rolled material due to the deformation of the rolling mill.

The surface roughness of each horizontal roll is preferably rough unless the rolled material is flawed, and the end of the horizontal roll through which the rolled material does not pass has an extremely increased coefficient of friction due to machining. This is more effective.

FIG. 3 is a schematic plan view showing an apparatus according to the second embodiment of the present invention. In the apparatus of the first embodiment described above, the barrel lengths of the upper horizontal rolls 1, 1'and the lower horizontal rolls 2, 2'are longer than the plate width of the rolled material 3, but in the apparatus of the second embodiment, , Meandering prevention devices A and A'provided on each of the inlet side and the outlet side of the final rolling mill 4.
The upper horizontal rolls 1, 1'of the lower horizontal rolls 1 and 2'are shorter than the strip width of the rolled material 3, and the lower horizontal rolls 2 and 2'are
It is longer than the plate width of the rolled material 3. Similar to the device of the first embodiment, each horizontal roll is movable in the vertical direction by the drive mechanism 5, 5 '.

It is desirable that the barrel ends of the upper horizontal rolls 1 and 1'be R-chamfered in order to prevent scratches on the surface of the rolled material when the rolled material is clamped. Further, the upper horizontal rolls 1 and 1'may be driven or not driven from the viewpoint of preventing meandering, but are driven and rotated in synchronization with the moving speed of the rolled material from the viewpoint of not causing surface flaws on the rolled material. Preferably.

As described above, before the leading end of the rolled material 3 passes through the exit side meandering prevention device A ', the horizontal rolls are retracted from the rolled material 3 in the state of being opened up and down. At the time when the leading end of the material 3 passes through the exit side meandering prevention device A ′, or when the rolling load cutting signal of the rolling mill upstream of the rolling mill 4 is generated, the drive mechanism 5,
The horizontal rolls are moved in the closing direction by 5 '.

As a result, the upper horizontal rolls 1 and 1 ′ having a barrel length shorter than the width of the rolled material plate arranged on the upper surface of the rolled material 3 and the two lower horizontal rolls disposed on the lower surface of the rolled material 3. 2 and 2 ', the rolled material 3 comes into surface contact at two places, and the upper horizontal rolls 1, 1'
Since the rolled material 3 is depressed in the central portion, the width-direction restraining force of the rolled material significantly increases. Therefore, it is possible to properly prevent the meandering of the tail end portion of the rolled material.

Further, since the rolled material 3 is sandwiched by the meandering preventive devices A and A ′ arranged on the inlet side and the outlet side of the rolling mill 4, additional rolling direction stress can be generated. As described above, it is possible to prevent the meandering of the tail end portion of the rolled material due to the deformation of the rolling mill.

FIG. 4 is a schematic plan view showing an apparatus according to the third embodiment of the present invention. In this embodiment, the barrel lengths of the upper horizontal rolls 1 and 1 ′ and the lower horizontal rolls 2 and 2 ′ of the meandering preventive devices A and A ′ provided on the inlet side and the outlet side of the final rolling mill 4 are Both are shorter than the strip width of the rolled material 3. Each horizontal roll has a drive mechanism 5,
As described above, it is possible to move vertically by 5 '.

The barrel ends of the upper horizontal rolls 1 and 1'and the lower horizontal rolls 2 and 2'are R-chamfered in order to prevent scratches on the surface of the rolled material when the rolled material is clamped. It is desirable to apply. Also,
Upper horizontal rolls 1,1 'and lower horizontal rolls 2,2'
From the viewpoint of preventing meandering, it may be driven rotation or non-driven rotation, but from the viewpoint of not causing surface flaws on the rolled material, it is preferable to rotate the driven material in synchronization with the moving speed of the rolled material.

As described above, before the leading end of the rolled material 3 passes through the exit side meandering preventive device A ', the horizontal rolls are retracted from the rolled material 3 while being opened vertically. When the leading end of the material 3 passes through the exit side meandering prevention device A ′ or when a rolling load cutting signal of a rolling mill upstream of the rolling mill 4 is generated, the drive mechanism 5,
The horizontal rolls are moved in the closing direction by 5 '.

As a result, the upper horizontal rolls 1 and 1 ', which are arranged on the upper surface of the rolled material 3 and have a barrel length shorter than the rolled material sheet width, and the two upper horizontal rolls 1 and 2 which also have a barrel length shorter than the rolled material sheet width. Rolled material 3 by lower horizontal rolls 2 and 2 '
Are in surface contact with each other at two places, and the upper horizontal rolls 1 and 1'and the lower horizontal rolls 2 and 2'are made of rolled material 3
Since it is in a state of being depressed in the central portion of, the width direction restraining force of the rolled material remarkably increases. Therefore, it is possible to properly prevent the meandering of the tail end portion of the rolled material.

Further, since the rolled material 3 is sandwiched by the meandering preventive devices A and A ′ arranged on the inlet side and the outlet side of the rolling mill 4, additional rolling direction stress can be generated. As described above, it is possible to prevent the meandering of the tail end portion of the rolled material due to the deformation of the rolling mill.

FIG. 5 intentionally shifts the parallelism of the rolling rolls in the final rolling mill to give a factor for causing meandering, and the upper horizontal rolls 1, 1'having a barrel length shorter than the strip width of the steel strip as a rolling material. The meandering preventive device of the third embodiment of the present invention including the lower horizontal rolls 2 and 2'is arranged, and the meandering amount when the steel strip is hot-finish rolled and the conventional mean shown in FIGS. It is the graph which showed the meandering amount when the meandering preventive device was arrange | positioned and the same steel strip as the above was hot-finished rolled by the same rolling schedule.

As is apparent from FIG. 5, the upper horizontal roll 1 of the present invention having a parrel length shorter than the width of the rolled material plate,
When a meandering preventive device consisting of 1'and lower horizontal rolls 2 and 2'is arranged and the rolled material is sandwiched, the meandering amount of the rolled material immediately before the final rolling mill is extremely reduced and is almost zero. Therefore, an excellent anti-meandering effect was obtained as compared with the case where the conventional anti-meandering device is arranged.

When the apparatus according to the present invention is used, even if the shape of the trailing end of the rolled material is asymmetrical extending to the driving side of the rolling mill, a folding accident does not occur, and from this point as well. It can be seen that the device of the present invention has a great effect of suppressing meandering. After the tail end of the rolled material has passed through the meandering prevention device arranged on the entrance side of the rolling mill, the meandering suppression effect does not work, but the meandering of the rolled material depends on the amount of meandering at that time. It is a phenomenon of expanding divergence system, and the meandering prevention device suppresses the meandering of the rolled material to the immediate vicinity of the roll bite entry side, so the tail end of the rolled material has passed through the meandering restraint device on the rolling machine entry side. It is possible to keep the amount of meandering afterwards extremely small.

[0038]

As described above, according to the present invention,
When continuously rolling a rolled material by a continuous rolling mill, it is possible to appropriately prevent the meandering that occurs when the rolled material leaves the rolling mill at the tail end of the rolled material, which is a useful industrial effect. Be brought.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a first embodiment of the device of the present invention.

FIG. 2 is a schematic plan view showing a first embodiment of the device of the present invention.

FIG. 3 is a schematic plan view showing a second embodiment of the device of the present invention.

FIG. 4 is a schematic plan view showing a third embodiment of the device of the present invention.

FIG. 5 is a graph showing a comparison of meandering amounts when a rolled material is hot finish-rolled by the apparatus of the present invention and the conventional apparatus.

FIG. 6 is a schematic side view showing a conventional meandering prevention device.

FIG. 7 is a schematic side view showing another conventional meandering prevention device.

[Explanation of symbols]

1 Upper horizontal roll 2 Lower horizontal roll 3 rolled material 4 rolling mill 5 Drive mechanism 6 looper 7 pinch rolls

Front Page Continuation (72) Inventor Shozo Higashi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nippon Kokan Co., Ltd. (56) Reference JP-A-10-118705 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) B21B 39/14 B21B 37/00

Claims (3)

(57) [Claims] To each 1. A final rolling mill inlet side and outlet side of the continuous rolling mill train comprising a plurality of rolling mill, rolls for clamping is provided a rolled material from above and below, the
The roll consists of at least three horizontal rolls.
Then, use the 3 horizontal rolls to roll the rolled material 2 times.
A meandering prevention device for a tail end portion of a rolled material in a continuous rolling mill, which is characterized in that it is held at more than one place . 2. At least one of the three horizontal rolls
The barrel length of one horizontal roll is smaller than the width of the rolled material.
The meandering prevention device for the tail end portion of a rolled material in a continuous rolling mill according to claim 1, characterized in that it is short . 3. A continuous rolling mill train comprising a plurality of rolling mills.
The upper rolls installed on the inlet and outlet sides of the final rolling mill.
Rolls and lower rolls roll the rolled material above and below
And to prevent the meandering of the tail end of the rolled material
And The rolled material is the upper roll and the lower roll on the exit side.
At the time of passing the rolling mill or above the final rolling mill.
At the time when the rolling load cut signal is generated in the current rolling mill
To close the upper roll and the lower roll respectively.
The rolled material is clamped by moving the rolled material in a direction.
Preventing meandering of the tail end of rolled material in continuous rolling mills
Law.