JP2023115952A - Pinch roll unit for thin-walled slab and apparatus and method for producing thin-walled slab - Google Patents

Abstract

To provide a pinch roll unit for a thin-walled slab capable of, even if a slab crown of a thin-walled slab changes in casting, maintaining the shape of the thin-walled slab constant and stabilizing casting while securing the controllability of meander with a pinch roll.SOLUTION: A pinch roll unit 40 for a thin-walled slab, for clamping a thin-walled slab 1 formed by continuous casting in a thickness direction and carrying the same, comprises: pinch rolls 41 for clamping the thin-walled slab 1; shape measuring means 43 that is provided further upstream in a transport direction F of the thin-walled slab 1 than the pinch rolls 41, for measuring the shape of the thin-walled slab 1 clamped by the pinch rolls 41; and pinch-roll deforming means 42 for deforming the pinch rolls 41. The pinch rolls 41 are deformed depending on the shape of the thin-walled slab 1 measured by the shape measuring means 43 so that the thin-walled slab 1 is clamped by the deformed pinch rolls 41.SELECTED DRAWING: Figure 2

Description

The present invention relates to a thin cast strip pinch roll unit that pinches and conveys a thin cast strip formed by continuous casting in the thickness direction, and a thin cast strip that is transported by the thin cast strip pinch roll unit. The present invention relates to a slab manufacturing apparatus and a thin cast slab manufacturing method.

As an apparatus for manufacturing a thin cast piece of metal, for example, as shown in Patent Documents 1 and 2, a pair of cooling rolls having a water-cooled structure inside and rotating in opposite directions are provided. Molten metal is supplied to the molten metal pool formed by the weir to form and grow a solidified shell on the peripheral surface of the cooling roll, and the solidified shells formed on the peripheral surfaces of the pair of cooling rolls are separated from each other at roll kiss points. A twin-roll continuous casting apparatus is provided for producing thin-walled slabs of a predetermined thickness by pressing. Such a twin roll type continuous casting apparatus is applied to various metals.

In the twin-roll continuous casting apparatus described above, the molten metal is continuously supplied from the tundish arranged above the chill roll to the molten metal pool through the submerged nozzle, and is cast on the outer peripheral surface of the rotating chill roll. Molten steel solidifies and grows to form a solidified shell, and the solidified shell formed on the outer peripheral surface of each chill roll is pressure-bonded at the roll kiss point to produce a thin cast slab.

Further, in Patent Document 3, a magnetic field generating device is arranged at the upper position of the tundish, and the molten steel surface is held in the direction of a pair of cooling rolls arranged in the vicinity of the central portion of the molten steel surface of the tundish. A method and apparatus for producing a thin-walled cast slab, in which a molten metal is brought into contact with the outer peripheral surface of a roll to grow a solidified shell, the solidified shells are pressed against each other at a roll-kiss point, and the obtained thin-walled slab is drawn upward. disclosed.

A thin cast piece continuously cast as described above is conveyed while being pinched in the thickness direction by pinch rolls.
Here, when meandering occurs during transportation of the thin cast slab, the thin cast slab cannot be stably transported, and casting may be stopped. In addition, the thin cast slab could not be wound in a good shape by the winding device, and the thin cast slab had to be rewound.
For this reason, various means have been proposed for controlling the meandering of the conveyed thin cast strip, as shown in Patent Documents 4 to 7 below.

In Patent Documents 4 to 6, according to the amount of meandering of the thin cast slab (the amount of offset from the conveying direction of the thin cast slab), the load on both ends of the pinch roll is varied to perform leveling, whereby the thin cast slab is leveled. There have been proposed means for suppressing the meandering of the .
Patent document 7 proposes means for suppressing meandering of thin cast slabs by shifting the parallelism of the rotating shafts of pinch rolls.
These meandering control technologies change the widthwise distribution of the pinch roll pressure applied to the thin cast slab, thereby applying a force in the thrust direction to the thin cast slab and guiding the slab in the direction opposite to the meandering direction to prevent meandering. I am canceling it.

JP-A-02-092438 JP 2017-087259 A JP-A-62-130750 JP-A-11-156504 JP-A-08-206790 Japanese Patent Publication No. 2003-522024 JP-A-08-215814

By the way, the cross-sectional shape of the thin cast slab perpendicular to the casting direction is generally convex, with the width central portion becoming thicker and the width becoming thinner toward the width end portions. The thickness curve from the center of the width to the width edge (hereafter referred to as the slab crown) and the thickness difference vary depending on the width and thickness of the thin slab, or the composition of the thin slab. can take Therefore, if the shape of the barrel of the pinch roll is set after assuming the shape of the slab crown in advance, it is possible to precisely design the control of the pressure distribution in the width direction, and the meandering can be controlled more stably and reliably. It becomes possible.

Here, in a thin cast slab formed by continuous casting, the slab crown may change during casting.
For example, at the beginning of casting, the mold (cooling rolls in a twin roll continuous casting machine) is not warm enough, and as the casting progresses and the mold gradually warms up, the shape changes due to the thermal expansion of the mold. , the slab crown may change accordingly.
Further, when the thickness of the cast plate is changed during casting, the heat flux of the mold changes, which may change the amount of thermal expansion of the mold and change the slab crown.

As described above, when the crown shape of a thin cast strip changes during casting, the width direction distribution of pressure changes every moment when meandering is controlled by the pinch rolls, and the meandering control is disturbed. I could have lost it.
In the following, the problem of the effect of pinch rolls on changes in slab crown will be described more specifically.

In the pinch rolls located closest to the mold, the temperature of the thin cast slab is higher and the thin cast slab is fragile and easily deformed, so the following phenomena occur more remarkably.
First, when the barrel shape of the pinch roll is set assuming the minimum value of the slab crown, when the slab crown takes the maximum value, the central part of the width of the thin slab is pressed excessively, It becomes difficult to apply a force in the thrust direction, and meandering controllability deteriorates. Furthermore, if the pressing force is excessively increased in order to control meandering, the width center of the thin cast slab is rolled and elongated, resulting in deterioration of the shape.
Conversely, if the barrel shape of the pinch roll is set assuming the maximum value of the slab crown, when the slab crown is at the minimum value, the width end of the thin slab will be pressed excessively, and the thin slab will be pushed to the end. As elongation, selvages are generated, which deteriorates the shape of the thin cast slab, and adversely affects the transportability after pinch rolls, meandering controllability, and coil windability.

The present invention has been made in view of the situation described above, and even if the slab crown of the thin slab changes during casting, the shape of the thin slab can be adjusted while ensuring the meandering controllability of the pinch rolls. It is an object of the present invention to provide a pinch roll unit for thin cast slabs, a thin cast slab manufacturing apparatus, and a thin cast slab manufacturing method capable of stabilizing casting by keeping constant.

In order to solve the above-described problems, a pinch roll unit for thin cast strips according to the present invention is a pinch roll unit for thin cast strips that pinches and conveys thin cast strips formed by continuous casting in the thickness direction. a pinch roll for pinching the thin cast piece; and a shape measuring means arranged upstream of the pinch roll in the conveying direction of the thin cast piece for measuring the shape of the thin cast piece pinched by the pinch rolls. and a pinch roll deforming means for deforming the pinch roll, the pinch roll is deformed according to the shape of the thin cast piece measured by the shape measuring means, and the deformed pinch roll It is characterized by sandwiching the thin cast piece.

According to the pinch roll unit for thin cast strips having the above-described configuration, the shape measuring means arranged upstream of the pinch rolls in the conveying direction of the thin cast strips measures the shape of the thin cast strips sandwiched between the pinch rolls. However, since the pinch roll deforming means is configured to deform the pinch rolls according to the measured shape of the thin cast slab, even if the slab crown of the thin cast slab changes during casting, The pinch rolls can be deformed in response to the changed billet crown shape.
Therefore, a part of the thin cast slab in the width direction is not locally strongly pressed, and the shape of the thin cast slab can be kept constant, and meandering control can be stably performed by the pinch rolls. It is possible to stably convey thin cast slabs.

Here, in the pinch roll unit for thin cast slabs of the present invention, the temperature of the thin cast slab sandwiched by the pinch rolls is measured, which is arranged upstream of the pinch rolls in the conveying direction of the thin cast slabs. Preferably, temperature measuring means are provided.
In this case, the temperature of the thin cast slab sandwiched between the pinch rolls can be measured, and the amount of deformation and pressing force of the pinch rolls can be adjusted in consideration of the strength of the thin cast slab. Deformation can be suppressed.

Further, in the pinch roll unit for thin cast strip of the present invention, the pinch roll deformation means may be a backup roll arranged on the back side of the pinch roll.
In this case, by bending the pinch rolls with the backup rolls, the pinch rolls can be deformed into a shape corresponding to the slab crown of the thin cast slab, and the thin cast slab can be stably conveyed. .

Further, in the pinch roll unit for thin cast strips of the present invention, the pinch roll deforming means may be outer diameter adjusting means disposed inside the pinch roll.
In this case, by adjusting the outer diameter of a part of the pinch rolls by the outer diameter adjusting means, it becomes possible to deform the pinch rolls into a shape corresponding to the slab crown of the thin cast slab, thereby stabilizing the thin cast slab. It is possible to transport

Further, in the pinch roll unit for thin cast strips of the present invention, a second shape for measuring the shape of the thin cast strip sandwiched between the pinch rolls is located downstream of the pinch rolls in the conveying direction of the thin cast strips. Measuring means may be provided.
In this case, the shape of the thin cast slab sandwiched between the pinch rolls is measured by the second shape measuring means, and the amount of deformation and the pressing force of the pinch rolls are adjusted according to the measurement result, whereby the thin cast slab is obtained. Deformation can be further suppressed.

Further, in the pinch roll unit for thin cast strips of the present invention, meandering detection means for detecting the amount of meandering of the thin cast strips is disposed on the upstream side of the pinch rolls in the conveying direction of the thin cast strips. good too.
In this case, the amount of meandering of the thin cast slab can be detected by the meandering detecting means, and the meandering control by the pinch rolls can be performed more stably.

A thin cast strip manufacturing apparatus of the present invention includes a continuous casting machine for continuously casting thin cast strips, and the pinch roll unit for thin cast strips described above. It is characterized in that the thin cast slab formed by the machine is sandwiched in the thickness direction and conveyed.
In the thin cast strip manufacturing apparatus having this configuration, the thin cast strip formed by the continuous casting machine is pinched and conveyed in the thickness direction by the thin cast strip pinch roll unit. Therefore, the meandering of the thin cast slab can be suppressed, and deformation of the thin cast slab can be suppressed, so that a high-quality thin cast slab with a stable shape can be produced.

Here, in the thin cast strip manufacturing apparatus of the present invention, the continuous casting machine supplies molten metal to a molten metal pool formed by a pair of rotating cooling rolls and a pair of side weirs, It is preferably a twin roll type continuous casting machine that forms and grows a solidified shell on the peripheral surface of the core to produce a thin cast slab.
In this case, it is possible to stably continuously cast thin cast slabs.

The thin cast strip manufacturing method of the present invention is characterized in that the thin cast strip formed by the continuous casting machine is pinched in the thickness direction by the thin cast strip pinch roll unit described above and conveyed.
In the thin cast strip manufacturing method having this configuration, the thin cast strip formed by the continuous casting machine is pinched and conveyed in the thickness direction by the thin cast strip pinch roll unit. Therefore, the meandering of the thin cast slab can be suppressed, and deformation of the thin cast slab can be suppressed, so that a high-quality thin cast slab with a stable shape can be produced.

Here, in the method for producing a thin cast strip of the present invention, the continuous casting machine supplies molten metal to a molten metal pool formed by a pair of rotating cooling rolls and a pair of side weirs. It is preferably a twin roll type continuous casting machine that forms and grows a solidified shell on the peripheral surface of the core to produce a thin cast slab.
In this case, it is possible to stably continuously cast thin cast slabs.

As described above, according to the present invention, even if the slab crown of the thin slab changes during casting, the shape of the thin slab can be kept constant while ensuring the meandering controllability of the pinch rolls. It is possible to provide a pinch roll unit for thin cast slabs that can be stabilized, an apparatus for manufacturing thin cast slabs, and a method for manufacturing thin cast slabs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic explanatory view of a thin cast piece manufacturing apparatus according to an embodiment of the present invention; FIG. 2 is a perspective explanatory view of the thin-wall cast piece manufacturing apparatus shown in FIG. 1 ; FIG. 2 is an enlarged explanatory view of the periphery of a cooling roll of the thin cast strip manufacturing apparatus shown in FIG. 1 ; BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing of the cross-sectional shape of the thin cast piece which is embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing of the pinch roll unit for thin cast strips which is embodiment of this invention. 6 is an explanatory view of pinch roll deforming means provided in the pinch roll unit for thin cast strip shown in FIG. 5. FIG. (Edited and written by Nippon Steel Corporation, "A book to understand iron and steel", November 10, 2004, Nippon Jitsugyo Publishing Co., Ltd., p.96) FIG. 4 is an explanatory diagram of the amount of bending of pinch rolls; FIG. 5 is an explanatory diagram of pinch roll deforming means provided in a pinch roll unit for thin cast strips, which is another embodiment of the present invention. FIG. 4 is an explanatory diagram of flatness in an example;

BEST MODE FOR CARRYING OUT THE INVENTION A pinch roll unit for thin cast strips, an apparatus for manufacturing thin cast strips, and a method for manufacturing thin cast strips, which are embodiments of the present invention, will be described below with reference to the accompanying drawings. In addition, this invention is not limited to the following embodiment.
Here, in the present embodiment, molten steel is used as the molten metal, and the thin cast slab 1 made of steel is manufactured. Further, in the present embodiment, the width of the thin cast piece 1 to be manufactured is in the range of 500 mm or more and 1500 mm or less, and the thickness is in the range of 1 mm or more and 5 mm or less.

As shown in FIGS. 1 and 2, a thin cast strip manufacturing apparatus 10 according to the present embodiment includes a continuous casting machine 20 for continuously casting a thin cast strip 1, and a thin cast strip 1 formed by the continuous casting machine 20. in the transport direction F.
The conveying unit 30 includes a thin cast strip pinch roll unit 40 that pinches and transports the thin cast strip 1 in the thickness direction, an in-line rolling mill 31, a looper 32, a coiler 33, a plurality of guide rolls 34, It has

As shown in FIG. 3, the continuous casting machine 20 includes a pair of cooling rolls 21, 21, side gates 25 disposed at the widthwise ends of the pair of cooling rolls 21, 21, and a pair of cooling rolls 21, 21. , 21 and side weirs 25, a tundish 28 for holding the molten steel 3 supplied to the molten steel pool portion 26, and an immersion nozzle 29 for supplying the molten steel 3 from the tundish 28 to the molten steel pool portion 26. It is considered to be a twin-roll continuous casting machine equipped with .

In this continuous casting machine 20, the molten steel 3 is cooled by contacting the cooling rolls 21, 21 rotating in the direction of rotation R, thereby forming solidified shells 5, 5 on the peripheral surfaces of the cooling rolls 21, 21. , and the solidified shells 5 formed on the pair of cooling rolls 21, 21 are pressed against each other at the roll kiss point, thereby casting a thin cast strip 1 having a predetermined thickness.
In the conveying section 30, the formed thin cast strip 1 is horizontally conveyed by the thin cast strip pinch roll unit 40, rolled to a predetermined thickness by the in-line rolling mill 31, and wound up by the coiler 33. be done.

As shown in FIG. 4, the thin cast slab 1 cast by the continuous casting machine 20 is generally thick at the center of the width and becomes thinner toward the ends of the width, thus presenting a convex shape. The thickness curve (slab crown) from the width center to the width end and the thickness difference can take various values depending on the width and thickness of the thin cast slab 1 or the composition of the thin cast slab.
In addition, the cross-sectional shape (slab crown) of the thin cast slab 1 may change during casting depending on the casting conditions and the like.

Therefore, in the thin cast strip pinch roll unit 40 of the present embodiment arranged in the conveying section 30, as shown in FIGS. Shape measuring means 43 arranged upstream of the pinch rolls 41, 41 in the conveying direction F of the thin cast strip 1 to measure the shape of the thin cast strip 1; 42, and the pinch rolls 41, 41 are deformed according to the shape (slab crown) of the thin cast strip 1 measured by the shape measuring means 43, and the deformed pinch rolls 41, 41 measure the thin cast strip. The slab 1 is sandwiched in the thickness direction.

In the present embodiment, as shown in FIGS. 2 and 5, the thin cast strip 1 sandwiched between the pinch rolls 41, 41 is located upstream of the pinch rolls 41, 41 in the conveying direction F of the thin cast strip 1. A temperature measuring means 44 is provided for measuring the temperature of .
In this embodiment, as shown in FIGS. 2 and 5, meandering detection means for detecting the amount of meandering of the thin cast strip 1 is provided upstream of the pinch rolls 41 and 41 in the conveying direction F of the thin cast strip 1. 45 are provided.
Furthermore, in this embodiment, as shown in FIG. A second shape measuring means 46 is provided for measuring.

Here, the shape measuring means 43 measures the shape of the conveyed thin cast piece 1. In this embodiment, the X-ray transmission mold plate extending in the width direction of the conveyed thin cast piece 1 is used. It is considered a thickness gauge.
By measuring the plate thickness in the width direction of the thin cast slab 1, the cross-sectional shape (slab crown) of the thin cast slab 1 can be measured. Further, by arranging the X-ray transmission plate thickness gauge to extend outside the width direction end of the thin cast strip 1, it is possible to detect meandering of the thin cast strip 1. That is, in this embodiment, the shape measuring means 43 also functions as the meandering detecting means 45 .

In this embodiment, the pinch roll deformation means 42 is a backup roll arranged on the back side of the pinch roll 41 .
As shown in FIG. 6, the pinch roll deformation means 42 is configured to deform the pinch roll 41 by bending the pinch roll 41 with a backup roll.
That is, in this embodiment, the amount of bending of the pinch rolls 41, 41 is adjusted by the backup rolls, which are the pinch roll deforming means 42, according to the shape of the thin cast strip 1 (the cast strip crown).
Here, the amount of bending is defined by the amount of deformation of the pinch rolls 41, 41 at the edge of the thin cast strip 1 before bending and after bending, as shown in FIG.

In this embodiment, the pinch rolls 41 do not need to be deformed so as to completely match the crown of the thin cast strip 1 .
Here, the amount of bending of the pinch rolls 41 is in the range of 10 μm to 150 μm when the width of the thin cast slab 1 is in the range of 500 mm to 1500 mm and the thickness is in the range of 1 mm to 5 mm. is preferred.

Further, in the present embodiment, as shown in FIGS. 2 and 5, the thin cast strip 1 sandwiched between the pinch rolls 41, 41 is located upstream of the pinch rolls 41, 41 in the conveying direction F of the thin cast strip 1. A temperature measuring means 44 for measuring the temperature of the pinch rolls 41, 41 is provided, and the deformation amount of the pinch rolls 41 and the pinch rolls 41, 41 is configured to adjust the pressing force of

In this embodiment, as shown in FIGS. 2 and 5, meandering detection means for detecting the amount of meandering of the thin cast strip 1 is provided upstream of the pinch rolls 41 and 41 in the conveying direction F of the thin cast strip 1. 45 is disposed, and the meandering of the thin cast strip 1 is controlled by controlling the operation of the pinch rolls 41, 41 according to the amount of meandering of the thin cast strip 1.
The meandering control method includes, for example, leveling control of the pinch rolls 41 and control of the cross angle of the pinch rolls.

Furthermore, in this embodiment, as shown in FIG. Since the second shape measuring means 46 is provided, the second shape measuring means 46 measures the shape of the thin cast slab 1 sandwiched between the pinch rolls 41, 41, and feeds back the measurement results. are configured to adjust the amount of deformation and the pressing force of the pinch rolls 41 , 41 .

In the thin cast strip pinch roll unit 40 of the present embodiment configured as described above, the shape measuring means 43 arranged upstream of the pinch rolls 41, 41 in the conveying direction F of the thin cast strip 1 measures the , the shape (slab crown) of the thin cast slab 1 sandwiched between the pinch rolls 41, 41 is measured, and the pinch roll deformation means 42 deforms the pinch rolls 41, 41 according to the measured shape of the thin cast slab 1. Therefore, even if the slab crown of the thin slab 1 changes during casting, the pinch rolls 41 can be deformed according to the changed slab crown shape.
Therefore, a part of the thin cast strip 1 in the width direction is not locally strongly pressed, and the shape of the thin cast strip 1 can be kept constant, and meandering control is stably performed by the pinch rolls 41. It is possible to stably convey the thin cast slab 1.

In this embodiment, the temperature measuring means 44 for measuring the temperature of the thin cast strip 1 sandwiched between the pinch rolls 41 is provided upstream of the pinch rolls 41 in the conveying direction F of the thin cast strip 1. , the temperature of the thin cast slab 1 sandwiched between the pinch rolls 41, 41 can be measured, and the deformation amount and pressing force of the pinch roll 41 can be adjusted in consideration of the strength of the thin cast slab 1, Deformation of the thin cast piece 1 can be suppressed.

Further, in the present embodiment, the pinch roll deformation means 42 is a backup roll arranged on the back side of the pinch roll 41. Therefore, by bending the pinch roll 41 with the backup roll, the pinch roll 41 is formed by thin casting. It becomes possible to deform the shape according to the slab crown of the slab 1, and the thin slab 1 can be conveyed stably.

Further, in the present embodiment, a second shape measuring means 46 for measuring the shape of the thin cast strip 1 sandwiched between the pinch rolls 41, 41 is provided downstream of the pinch rolls 41 in the conveying direction F of the thin cast strip 1. By adjusting the amount of deformation and the pressing force of the pinch rolls 41 according to the shape of the thin cast strip 1 measured by the second shape measuring means 46, the thin cast strip 1 can be further deformed. can be suppressed.

Further, in this embodiment, the shape measuring means 43 arranged upstream of the pinch rolls 41 in the conveying direction F of the thin cast strip 1 functions as a meandering detection means 45 for detecting the meandering amount of the thin cast strip 1. Therefore, the amount of meandering of the thin cast slab 1 can be detected by the meandering detector 45, and the pinch rolls 41 can control meandering, so that the thin cast slab 1 can be conveyed more stably. .

The thin cast strip manufacturing apparatus 10 of the present embodiment and the thin cast strip manufacturing method of the present embodiment include a continuous casting machine 20 and a thin cast strip pinch roll unit 40 of the present embodiment. Since the thin cast strip 1 formed by the continuous casting machine 20 is pinched and conveyed in the thickness direction by the thin cast strip pinch roll unit 40, meandering of the thin cast strip 1 is suppressed. In addition, deformation of the thin cast slab 1 can be suppressed, and a high-quality thin cast 1 with a stable shape can be manufactured.

Here, in the present embodiment, the continuous casting machine 20 supplies the molten steel 3 to the molten steel pool portion 26 formed by the pair of rotating cooling rolls 21, 21 and the pair of side weirs 25, and the cooling rolls 21, 21 Since it is a twin-roll continuous casting machine that forms and grows the solidified shells 5, 5 on the peripheral surface of the to manufacture the thin cast slab 1, it is possible to continuously cast the thin cast slab 1 stably. .

The pinch roll unit 40 for thin cast strips, the apparatus for manufacturing thin cast strips 10, and the method for manufacturing thin cast strips, which are embodiments of the present invention, have been specifically described above. It is not limited to this, and can be changed as appropriate without departing from the technical idea of the invention.
In the present embodiment, the twin-roll continuous casting machine shown in FIG. 3 is used as an example of the continuous casting machine, but the present invention is not limited to this, and any machine that continuously casts thin cast slabs may be used. .

Further, in the present embodiment, the pinch roll deforming means has been described by exemplifying the backup roll arranged on the back side of the pinch roll, but it is not limited to this. For example, as shown in FIG. 8, the pinch roll deforming means 42 may be outer diameter adjusting means 50 disposed inside the pinch roll 41 . The outer diameter adjusting means 50 includes a guide hole 51 having a tapered surface that gradually inclines radially inward from the width end portion toward the width center portion, and is inserted into the guide hole 51 so as to follow the tapered surface. cores 52, 52 respectively moving along. A central hydraulic chamber 53 is formed in the width center of the guide hole 51 (between the cores 52 and 52), and end hydraulic chambers 54, 54 are formed in width end portions of the guide hole 51. .
By adjusting the hydraulic pressures in the central hydraulic chamber 53 and the end hydraulic chambers 54, 54, the core 52 is moved in the width direction, thereby adjusting the outer diameter of the pinch roll 41 at the width center. It is said that

The results of experiments conducted to confirm the effects of the present invention will be described below. Thin cast slabs were manufactured using the apparatus for manufacturing thin cast slabs shown in FIGS.

The cooling roll had a width of 1000 mm, a diameter of 1200 mm, and an internal Cu sleeve water cooling type.
Four pinch roll units were provided, with a work roll diameter of 200 mm (internal water cooling) and a backup roll diameter of 400 mm. Both the work roll and the backup roll were flat. As the pinch roll unit closest to the continuous casting machine, the pinch roll unit 40 for thin cast slab described in the present embodiment was used.

Also, the casting conditions were set as follows.
Steel type: low carbon aluminum killed steel (0.05% by mass C-0.03% by mass Al)
Casting speed: 50 m/min Cast plate thickness: 3.5 mm
1 cast molten steel amount: 20t
Time from start of casting to steady state: 3 minutes Time from start of casting to end of casting (when casting is completed): 15 minutes Meandering control method: pinch roll, leveling control.

In the present invention example, the shape of the thin cast slab was measured, and the pinch rolls were deformed according to the slab crown of the thin cast slab. In the comparative example, no deformation of the pinch rolls was performed.
The obtained thin cast strip was recoiled after being completely wound, and the maximum flatness was evaluated for the entire length by a two-dimensional flatness meter as shown in FIG. Table 1 shows the evaluation results.

In the comparative example, since the pinch rolls were not deformed according to the shape of the thin cast slab, the meandering of the thin cast slab could not be sufficiently controlled. For this reason, at the time of casting 10 tons, the amount of meandering exceeded 70 mm and the edge of the thin cast slab came into contact with the housing of the in-line rolling mill, and casting was stopped. In addition, the thin cast slab exhibited medium elongation (wavy at the width center), and its maximum flatness was 4.8%.
In the present invention example, since the pinch rolls were deformed according to the shape of the thin cast slab, the meandering of the thin cast slab could be sufficiently controlled, and the meandering amount was 27 mm at maximum. In addition, the thin cast slab was slightly elongated (wavy at both ends), and its maximum flatness was 1.2%.

From the above experimental results, according to the present invention, even if the slab crown of the thin slab changes during casting, the shape of the thin slab can be kept constant while ensuring the meandering controllability of the pinch rolls. It was confirmed that it is possible to provide a pinch roll unit for thin cast slabs, a thin cast slab manufacturing apparatus, and a thin cast slab manufacturing method that can stabilize the .

1 thin cast slab 3 molten steel (molten metal)
5 solidified shell 10 thin cast slab manufacturing device 20 continuous casting machine 21 cooling roll 25 side weir 26 molten steel pool (molten metal pool)
40 pinch roll unit for thin cast slab 41 pinch roll 42 pinch roll deforming means 43 shape measuring means 44 temperature measuring means 45 meandering detecting means 46 second shape measuring means

Claims (10)

A pinch roll unit for thin cast strips that pinches and conveys thin cast strips formed by continuous casting in the thickness direction,
a pinch roll for sandwiching the thin cast piece;
a shape measuring means arranged upstream of the pinch rolls in the conveying direction of the thin cast slab for measuring the shape of the thin cast slab sandwiched between the pinch rolls;
and pinch roll deformation means for deforming the pinch roll,
A pinch roll unit for thin cast slab, characterized in that the pinch rolls are deformed according to the shape of the thin cast slab measured by the shape measuring means, and the thin cast slab is pinched by the deformed pinch rolls. . 2. The method according to claim 1, further comprising temperature measuring means arranged upstream of the pinch rolls in the conveying direction of the thin cast slab for measuring the temperature of the thin cast slab sandwiched between the pinch rolls. A pinch roll unit for thin-walled slabs as described. 3. The pinch roll unit for thin cast strip according to claim 1, wherein the pinch roll deforming means is a backup roll arranged on the back side of the pinch roll. 3. The pinch roll unit for thin cast strip according to claim 1, wherein said pinch roll deforming means is outer diameter adjusting means arranged inside said pinch roll. 2. A second shape measuring means for measuring the shape of the thin cast strip sandwiched between the pinch rolls is disposed downstream of the pinch rolls in the conveying direction of the thin cast strip. The pinch roll unit for thin cast strips according to any one of claims 1 to 4. 6. A meandering detector for detecting a meandering amount of the thin cast strip is disposed upstream of the pinch roll in the conveying direction of the thin cast strip. A pinch roll unit for thin cast slab according to item 1. A continuous casting machine that continuously casts thin-walled slabs, and a pinch roll unit for thin-walled slabs according to any one of claims 1 to 6,
An apparatus for producing a thin cast strip, wherein the thin cast strip formed by the continuous casting machine is pinched and conveyed in a thickness direction by the pinch roll unit for the thin cast strip. The continuous casting machine supplies molten metal to a molten metal pool formed by a pair of rotating cooling rolls and a pair of side weirs, and forms and grows a solidified shell on the peripheral surface of the cooling rolls to form a thin cast slab. 8. The apparatus for producing thin cast slabs according to claim 7, wherein the apparatus is a twin roll type continuous casting machine for producing . A thin cast strip, characterized in that a thin cast strip formed by a continuous casting machine is pinched in the thickness direction and conveyed by the pinch roll unit for thin cast strip according to any one of claims 1 to 6. How to make pieces. The continuous casting machine supplies molten metal to a molten metal pool formed by a pair of rotating cooling rolls and a pair of side weirs, and forms and grows a solidified shell on the peripheral surface of the cooling rolls to form a thin cast slab. 10. The method for producing a thin cast slab according to claim 9, wherein the twin roll type continuous casting machine produces

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