JPH0716767B2 - Method and apparatus for continuous casting of metal ribbon - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method and apparatus for continuously casting a metal ribbon without adhering a solidified material to a side weir that abuts against a cooling roll.

[Conventional technology]

There is a so-called twin roll type continuous casting device as a device for pouring molten metal such as molten steel onto the surface of a cooling roll and continuously casting the molten metal into a thin strip. As such a continuous casting apparatus, for example, as shown in JP-A-57-94456, one cooling roll and the other cooling roll can be moved in the same plane in the axial direction. It is known that a side weir is arranged and a side weir is provided from the side surface of one cooling roll to the peripheral surface of the other cooling roll.

In this type of continuous casting apparatus, the width of the molten metal pool formed between the pair of rolls can be adjusted to the desired strip width of the strip product by changing the amount of displacement of the cooling rolls. Therefore, products of various sizes can be manufactured by one device.

[Problems to be solved by the invention]

When a metal strip is manufactured using a continuous casting machine of this type, the molten metal solidifies on the surface of the side dam to form a shell. This solidified shell moves downward as the chill roll rotates, but receives a large rolling down force in the vicinity of the caching point and tries to spread laterally. Therefore, the side dam receives a force to be pushed out to the side, and the position of the side dam with respect to the cooling roll changes from the set value.

For example, on the side surface of the cooling roll, the gap between the side surface and the side weir expands, so that pouring into the gap causes a large casting burr and a dangerous state such as molten metal leak. Further, on the circumferential surface of the cooling roll, the side weir is laterally displaced, so that the width of the metal ribbon as a product becomes unstable.

In this regard, Japanese Patent Laid-Open No. 60-170559 discloses that the side weir that is in contact with the side surface of the cooling roll is swung. This proposal forms a molten metal pool by arranging a pair of cooling rolls without shifting in the axial direction and providing side weirs over the side surfaces of both cooling rolls for the purpose of producing a metal strip having a constant width. ing. Due to such a roll arrangement, the side weir can be horizontally swung to prevent the adhered matter from adhering.

However, in order to be able to adjust the width of the metal ribbon as a product, in a device of the type in which a side weir is provided between one cooling roll and the other cooling roll,
It is not possible to employ the vibration imparting mechanism as disclosed in JP-A-60-170559.

In addition, since the side weir shown in the publication is oscillated in the horizontal direction, it facilitates the pointing of molten metal to the gap between the cooling roll and the side weir, and the occurrence of casting burrs increases with casting time. Finally, it becomes difficult to secure stable casting for a long time.

Therefore, the present invention eliminates the influence of the solidification shell generated in the vicinity of the side weir in a continuous casting apparatus of a type in which a pair of cooling rolls is combined so that the plate width of the product can be freely adjusted, and under stable conditions. The purpose is to produce a metal ribbon.

[Means for solving problems]

In order to achieve the object, in order to achieve the object, the method for continuously casting a metal strip of the present invention is to perform rapid solidification of the molten metal supplied to the space between a pair of cooling rolls arranged in parallel to pass through a gap between the rolls to rapidly cool the metal strip When manufacturing the strip, the axial positions of the cooling rolls are shifted from each other, and a side weir is provided from the side surface of one cooling roll to the peripheral surface of the other cooling roll, which corresponds to the width of the target thin metal strip. A molten metal pool is formed, and the side dam is vibrated in the circumferential direction along the circumferential surface of the cooling roll.

Further, the apparatus for carrying out this method has a side surface shape along the peripheral surface of one cooling roll so as to face the other cooling roller so as to be movable in the axial direction on the same plane. The side weir is arranged from the side surface of one cooling roll to the peripheral surface of the other cooling roll, and a vibration applying mechanism for vibrating the side weir along the peripheral surface of the cooling roll is provided.

〔Example〕

Hereinafter, the features of the present invention will be specifically described by way of examples with reference to the drawings.

FIG. 1 is a perspective view showing a main part of a continuous casting apparatus used in this example.

In this continuous casting apparatus, one cooling roll 2 is arranged parallel to the other cooling roll 2 on the same plane. The other cooling roll 2 can be moved in its axial direction, whereby the distance L between the side surface 1a of the one cooling roll 1 and the side surface 2a of the other cooling roll 2 can be appropriately adjusted. Further, the cooling roll 2 is arranged so as to be close to and away from the cooling roll 1, whereby the gap d (see FIG. 2) between the cooling rolls 1 and 2 is adjusted.

Then, the side surfaces 1a, 2 of one of the cooling rolls 1 and 2 are divided so as to partition the sides of the upper space formed by the peripheral surfaces of the cooling rolls 1, 2.
Side weir 3 from a to the peripheral surfaces 1b and 2b of the other cooling roll
Is provided. This side weir 3 is a cooling roll 1,2
Surface portions that abut the side surfaces 1a and 2a, and end surfaces that abut the peripheral surface portions 1b and 2b. In this way, the cooling roll 1,
A space surrounded by the peripheral surfaces 1b, 2b of 2 and the side dam 3 is created, and a molten metal pool 4 is formed by pouring the molten metal into the space from above.

The molten metal pool 4 is cooled at the portions in contact with the cooling rolls 1 and 2, and becomes a solidified shell 5 as shown in FIG. The solidified shell 5 moves in the direction of the roll gap 6 by the rotation of the cooling rolls 1 and 2. In the process of this movement, the solidified shell 5 grows and is pressed by the cooling rolls 1 and 2 in the roll gap 6 to form an integral ribbon 7.

At this time, the widthwise end of the molten metal pool 4 is partitioned by the side weir 3, but heat is radiated through the side weir 3 to form a solidified shell in the portion facing the side weir 3. In this solidified shell, since the side dam 3 is vibrated along the circumferential direction of the cooling rolls 1 and 2, the slabs are not connected to each other, and the slab ruptures and breakouts due to tearing of the slab ends. Can be prevented. Furthermore, by swinging the vibration of the side weir in the circumferential direction of the cooling roll, the amount of water flowing into the gap between the side weir and the cooling roll is reduced compared to the conventional method (horizontal direction), and the increase of casting burr is suppressed. Enables long-term casting.

FIG. 3 is a diagram showing an example of a mechanism for imparting circumferential vibration to the side dam 3. The side weir 3 is pressed against the body surface and side surface of the cooling roll with a constant surface pressure by the hydraulic cylinders 7 and 8.

Further, the hydraulic cylinder 7 is connected to a vibrating device (not shown), and swings the side dam 3 in the roll circumferential direction.

The vibration applied to the side dam 3 is appropriately selected in relation to the casting speed, but normally, mechanical vibration having an amplitude of several mm and a frequency of 1 to 100 Hz can be adopted. Ultrasonic vibration is also effective as a similar effect.

〔The invention's effect〕

As described above, in the present invention, since the vibration along the circumferential surface direction of the cooling roll is applied to the side dam,
The solidified shell is prevented from sticking to the gap where the side dam contacts the peripheral surface and the side surface of the cooling roll. for that reason,
Since the gap between the side surface and the peripheral surface of the cooling roll and the side dam can be maintained at the set value, the casting burr becomes large due to the invasion of the molten metal into the gap, or the end of the cast metal ribbon is There are no drawbacks such as tearing off or leakage of hot water. In this way, according to the present invention, it becomes possible to manufacture a metal ribbon under stable conditions for a long time.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a continuous casting apparatus according to an embodiment of the present invention, FIG. 2 illustrates a state where a metal ribbon is manufactured from molten metal, and FIG. 3 is attached to the apparatus. An example of a vibration imparting mechanism is shown.

Claims (2)

[Claims] 1. When manufacturing a metal ribbon by rapidly solidifying molten metal supplied to a space between a pair of cooling rolls arranged in parallel and passing through a roll gap, the axial positions of the cooling rolls are mutually changed. And a side weir is provided from the side surface of one cooling roll to the peripheral surface of the other cooling roll to form a molten metal pool corresponding to the width of the target metal ribbon, and the side weir is provided on the peripheral surface of the cooling roll. A method of continuously casting a thin metal strip, which comprises vibrating in a circumferential direction along a line. 2. One of the cooling rolls faces the other cooling roll so as to be movable in the axial direction on the same plane,
A side dam having a side surface shape along the peripheral surface of the cooling roll is arranged from the side surface of one cooling roll to the peripheral surface of the other cooling roll, and the side dam is vibrated along the peripheral surface of the cooling roll. A continuous casting device for a thin metal strip, which is provided with a vibration imparting mechanism.