JPH05253650A - Twin roll type continuous casting apparatus - Google Patents

Abstract

PURPOSE:To prevent particularly, the flowing of molten metal near two side weir parts sandwiching rolls and the development and the stickness of solidified material around the side weirs. CONSTITUTION:In a casting apparatus 1, parting members 8, 9 having the width smaller than the whole width of the rolls 2, 3 and dipped into a molten metal pouring basin part 7 paralleled to the solidified starting lines (d), (e) are provided. By the parting members 8, 9, entrapment of scum into the outer peripheral surfaces 2a, 3a of the rolls is prevented and waving on the molten metal surface is reduced. As the end parts 8a, 9a of the parting members 8, 9 are bent in the reverse direction to the facing rolls 2, 3, the molten metal flow toward the side weir 4, 5 sides is deflected, and the flowing of high temp. molten metal toward the lower part of the side weir is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a twin roll type continuous casting apparatus for continuously casting a thin metal plate directly from a molten metal.

[0002]

2. Description of the Related Art In recent years, a casting method for continuously producing a thin plate from a molten metal such as molten steel has attracted attention, and a twin-roll continuous casting method is one of them. This is because a pair of rolls that rotate in opposite directions are arranged in parallel and opposite to each other with an appropriate gap, and two side dams (side dams) are pressed against both end faces of these rolls, and the rolls are placed above the gap. The outer peripheral surface and the side weir define a molten metal pool, and the molten metal in the pool is continuously supplied from a pouring device installed above the molten pool to rotate the molten metal in the pool. In this method, a solidified shell is generated while cooling on a surface to continuously cast a thin metal plate.

In this continuous casting method, if a large amount of scum (oxide of molten metal) generated on the surface of the molten metal pool is caught in the solidified shell, the surface properties of the thin metal sheet to be cast and the material itself are adversely affected. Since it will not affect the quality, it will significantly reduce its quality.
No. 24176 discloses a roll width direction (roll axis direction).
A continuous casting device is disclosed in which a pair of partition plates are immersed in the molten metal pool over the entire length thereof to prevent the flow of scum toward the outer peripheral surface of the roll on the molten metal surface.

[0004]

However, in the above continuous casting apparatus, since each partition plate is arranged in contact with the side weirs provided at both ends of the roll, solidified matter is generated around this contact portion. The solidified product interferes with and coalesces with the solidified shell on the roll surface, or the solidified product peels off and is wound into the slab, whereby a solidified shell with a uniform thickness can be generated along the entire width direction of the roll. However, it may cause so-called poor solidification.

Further, in a general twin-roll type continuous casting apparatus, the molten metal discharged from the molten metal nozzle of the pouring device usually moves toward the outer peripheral surface of the roll in the molten metal pool portion and then descends. In the above apparatus, since the partition plate is arranged in that direction, the flow changes to the side weir side along the partition plate, and this molten metal flow hits the side weir and flows downward. For this reason, at the end of the roll, the molten metal flow delays the formation and growth of the solidified shell compared to other parts, resulting in defective shapes and breakout at the end of the cast piece (a phenomenon in which the melt flows out of the cast piece due to poor solidification). There is a fear.

In view of the above problems, the present invention has an object to provide a continuous casting apparatus that prevents the scum from being caught and does not cause the above-mentioned poor solidification around the partition plate or the solidification delay at the end of the slab. To do.

[0007]

According to the present invention for the above object, a pair of rolls rotating in mutually opposite directions are arranged parallel to each other and side weirs are pressed against both end faces of the pair of rolls. In the twin roll type continuous casting device that defines the molten metal pool portion by the outer peripheral surface of the roll and the side dam and continuously casts the thin metal plate through the gap between the rolls, a width smaller than the entire width of the roll is set. A partition member having substantially the same as the contact line between the molten metal surface and the outer peripheral surface of each roll is immersed in the molten metal surface of the molten metal pool corresponding to each roll, and at the side dam side of the partition member. There is provided a twin-roll type continuous casting apparatus, characterized in that both ends of each are bent in the opposite direction to the corresponding rolls.

[0008]

Since the partition member has a width smaller than the entire width of the roll, it does not contact the side dam. Therefore, when the side weir and the partition member come into contact with each other, a solidified product is generated at the contact point and interferes with and coalesces with the solidified shell on the roll surface.
Alternatively, it is possible to prevent nonuniformity of the thickness of the solidified shell in the roll width direction, which is caused when the solidified product is peeled off and rolled into the slab. Further, since both ends of the partition member are bent in the opposite direction to the roll, the high-temperature molten metal flows toward the side dam side along the partition member are deflected by the bent parts and interfere with each other, and The downward flow of the molten metal is weakened, and the inhibition of solidified shell formation due to the high temperature molten metal flow can be prevented.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic appearance of a twin-roll type continuous casting apparatus 1 (hereinafter, abbreviated as casting apparatus 1) according to the present invention, and both ends of a pair of rolls 2 and 3 facing each other with a gap of a predetermined width. Fan-shaped side weirs 4 and 5 are pressed against the surface.

At the time of casting, the rolls 2 and 3 are rotationally driven in opposite directions as shown by arrows a and b in the figure by a drive mechanism (not shown), and the outer peripheral surfaces 2a and 3a of the rolls 2 and 3 and both sides thereof are driven. In the space defined by the weirs 4 and 5,
A molten metal (molten metal) 6 represented by stainless steel (for example, SUS304) is supplied from a pouring device (not shown) located above the molten metal as shown by an arrow c. 7 is formed.

According to the present embodiment in the casting apparatus 1 configured as described above, in the basin 7 is a partition member which is made of a refractory material and which blocks the flow of scum toward the outer peripheral surfaces 2a and 3a of the rolls. 8 and 9 are provided. The partition members 8 and 9 are supported by, for example, a pouring device located above the partition members 8 and 9. The partition members 8 and 9 have a width slightly smaller than the width of the rolls 2 and 3 as shown in the drawing, It is arranged so as to extend toward the molten metal surface 7a and be immersed in the molten metal pool 7 at its lower end. According to the present embodiment, the partition members 8 and 9 are sandwiched between the two partition members 8 and 9 in order to make the pouring port to the molten metal pool 7 as large as possible and to facilitate pouring. It is dipped with an inclination with respect to the molten metal surface 7a so that the spatial cross-sectional area gradually expands upward from the molten metal pool 7.

Further, in the partition members 8 and 9, the immersion lines 8'and 9'with the hot water pool portion 7 along the roll width direction are defined by the hot water surface 7a.
And the outer peripheral surfaces 2a and 3a of the rolls and the contact lines d and e (solidification start line) are arranged so as to be substantially parallel to each other with a gap 10 therebetween, and are further positioned on both side dams 4 and 5 in the width direction. Both ends 8a and 9a are bent and formed in the opposite direction to the corresponding rolls 2 and 3.

Partition members 8 and 9 configured as described above
The operation of will be described with reference to FIGS. 2 and 3. 2 is an external view of the pool part 7 of the casting apparatus 1 shown in FIG. 1 as seen from above, and FIG. 3 is a view showing the interior of the pool part near the end of the partition member. As shown in FIG. 2, the molten metal 6 poured into the space of the pool 7 sandwiched between the two partition members 8 and 9 is rotated by the rotation of the rolls 2 and 3 in the directions of arrows a and b, and the outer peripheral surface of the rolls is rotated. 2a, 3a, this flow collides with the partition members 8, 9 located in front of them, where the roll rotation axes A, B
It is deflected to the flow parallel to and toward both side weirs 4, 5.

However, the flow toward the side weirs 4, 5 is caused by both ends 8a, 9a of the partition members 8, 9 which are bent in the opposite direction to the corresponding rolls 2, 3.
It will be deflected to the side away from the corresponding rolls 2, 3. As a result, both end portions 8 of the two partition members 8 and 9 are
In the region sandwiched by a and 9a, the two deflected flows interfere with each other and the flow components are weakened, so that there is no so-called bent side as shown by the dotted arrow in FIG. The downward flow tendency of the high-temperature molten metal after the collision with the dam is weakened, and defects such as defective shape and breakout of the slab ends due to delay in solidification of both ends of the slab 11 are prevented.

Further, according to this embodiment, as is clear from FIG. 2, the width of the partition members 8 and 9 is smaller than the entire width of the rolls 2 and 3, so that the partition members 8 and 9 are provided on both side dams 4 and 5.
Since it is not supported on the basin 7 in a state of being in contact with, there is no possibility that a solidified product is generated or adhered to the ends of the partition members 8 and 9 and the surfaces of the side dams 4 and 5. ,
The generated solidified material comes into contact with or interferes with the solidified shell on the roll outer peripheral surfaces 2a and 3a, or the solidified material falls off and is caught between the rolls 2 and 3, and the thickness of the cast slab 11 becomes uneven; Coagulation failure such as does not occur.

When the partition members 8 and 9 are installed, the solidification start lines d and 3
Disturbance of e is reduced, a stable solidified shell generation line is formed, and the inclusion of scum on the molten metal surface is prevented.

[0017]

As described above, according to the present invention, in the twin roll type continuous casting apparatus, the partition member having a width smaller than the entire width of the roll is provided in the pool of the molten metal so that the end of the partition member is solidified. No matter is formed or solidified matter adheres. Further, since the end of the partition member is bent in the opposite direction to the corresponding roll, the inflow of high temperature molten metal into the side dam is prevented, and defects such as poor solidification and breakout due to solidification delay at the end of the cast slab are prevented. Can also be resolved.

[Brief description of drawings]

FIG. 1 is a schematic external perspective view of a twin roll type continuous casting apparatus according to the present invention.

FIG. 2 is a top view of the device of FIG.

FIG. 3 is a model diagram showing a molten metal flow around an end portion of a partition member.

[Explanation of symbols]

 1 ... Twin roll type continuous casting device 2, 3 ... Rolls 4, 5 ... Side weir 6 ... Molten metal (molten metal) 7 ... Hot water pool part 8, 9 ... Partition member 11 ... Metal thin plate

(72) Inventor Hideki Oka 3434, Shimada, Hikari City, Yamaguchi Prefecture, Shinko Nippon Steel Co., Ltd., Hikari Steel Works Co., Ltd. (72) Inventor, Yamada, 3434 Shimada, Hikari City, Yamaguchi Prefecture, Nippon Steel Hikari Steel Works (72) Inventor Takashi Arai 3434 Shimada, Hikari City, Yamaguchi Prefecture Nippon Steel Works Hikari Steel Works Co., Ltd.

Claims (1)

[Claims] 1. A pair of rolls (2), (3) that rotate in mutually opposite directions are arranged in parallel and face each other, and side dams (4), (5) are provided on both end faces of the pair of rolls (2), (3). ) Is pressure-welded, the molten metal pool (7) is defined by the outer peripheral surfaces of the rolls (2) and (3) and the side dams (4) and (5), and the thin metal plate is passed through the gap between the rolls. In a twin roll type continuous casting device for continuously casting, a partition having a width smaller than the entire width of the rolls (4) and (5) and extending substantially parallel to the contact line between the molten metal surface and the outer peripheral surface of each roll. Replace the members (8) and (9) with the rolls (2) and
Corresponding to (3), it is immersed in the molten metal surface of the basin (7), and both end portions (8a) and (9a) of the partition members (8) and (9) on the side dam side are corresponding rolls. (2),
A twin roll type continuous casting device characterized by being bent in the opposite direction to (3).