JPS58212844A - Continuous casting device for thin plate - Google Patents

Abstract

PURPOSE:To provide a titled device which can produce and supply a thin plate having high quality stably by disposing a water cooled roll of a small diameter diagonally above a water cooled roll with a caliber of a large diameter and forming a side dam to be stored therein with molten metal in the space enclosed of both water cooled rolls and the caliber. CONSTITUTION:Molten metal 15 is supplied continuously at a specified rate from a tundish 17 into the space formed of a side dam 14 and both water cooled rolls 11, 13 througs a charging nozzle 6. The sealing of the metal 15 on the side accomplished by the side dam 14 up to a line P (the bottom end line of the side dam) and by a caliber 12 after the line P. The solidified shells 9, 9' formed in contact with the rolls 11, 13 are rolled to one body to a thin plate 13 which is separated from the roll 11 by a knife edge 19. Pinch rolls 20 are driven in synchronization with the rolls 11, 13 to transfer the plate 13 to the next stage. Since the head of the molten metal is low and the static pressure of the molten metal is low in this method, there is no generation of bulging, hence the internal quality of the ingot formed by the same is good and the shape of the ingot is good as well.

Description

[Detailed description of the invention] The present invention relates to improvements in continuous thin plate casting equipment.

An outline of a conventional two-drum continuous caster casting apparatus will be explained with reference to FIG. This device consists of two water-cooled rolls 1.1' arranged in parallel with a gap corresponding to the thickness of the plate to be cast, side dams 2.2 arranged in contact with both sides of the rolls, and the rolls. 1.1' and the side dam 2.2, a pouring nozzle 4 for injecting molten metal 3 such as molten steel, a guide roll 6 for guiding the cast and rolled thin plate 5, and a guide roll 6 for guiding the thin plate 5. The main components include pinch rolls 7 for transportation, and the pouring nozzle 4 is connected to a tundish 8 to draw out the molten metal 3 in the tundish 8.

The two water-cooled rolls 1.1' are installed to face each other horizontally, and are driven to rotate in opposite directions (indicated by arrows) by a drive device (not shown).

This water-cooled roll 1.1' is made of copper, copper alloy, or steel, and has a built-in water-cooling mechanism, and has a fairly large diameter in order to obtain an appropriate contact area with the molten metal 6. There is. Said site dam 2.2 ke, fireproof,
Made of materials with excellent heat resistance, such as ceramics,
A molten metal filter is stored between the water-cooled roll 1.1' and the molten metal 6 is pressed against both ends of the roll to prevent leakage of the molten metal 6 to the outside. The guide roll 6 guides the manufactured thin plate 5 in a predetermined direction, and the pinch roll 7 is driven in synchronization with the water-cooled rolls 1 and 1' to transport the thin plate 5 to the next process.

The molten metal 3 is supplied to a tundish 8 and is continuously and quantitatively supplied between water-cooled rolls 1.1' via a pouring nozzle 4. In the pool of molten metal 3 formed by the water-cooled roll 1.1/ and the side dam 2.2, the molten metal 3 is
' is cooled and a solidified shell 9 is formed. The water-cooled rolls 1.1' rotate in different directions, and two solidified shells 9.1' are formed on the surface of each water-cooled roll.
9' are collected, rolled, integrated, and sent out as one thin plate 5. This thin plate 51 is guided by a guide roll 6 to a pinch roll 7, and pulled out by the pinch roll 7 at a predetermined speed. In this case, the thickness T of the thin plate 5 is the water-cooled roll 1.1
By adjusting this gap, the desired plate thickness can be obtained.The following are the drawbacks of this conventional device.

(1) Because the molten metal head is high, the static pressure of the molten metal increases, resulting in a bulging phenomenon in the slab, which causes internal cracks, segregation, and
It is easy for slab shape defects to occur.

(11) Solidified shell 9. ．． When integrating 9' by rolling,
Water-cooled roll 1.1' receives rolling reaction force, but roll 1.1'
' is a large-diameter roll with the same diameter, so the rolling reaction force is large (it becomes difficult to maintain the precision of the roll gap, the shape of the slab tends to be defective, and the roll structure becomes complicated.

1ii1 Molten metal is poured into the space surrounded by the water-cooled roll 1.1' and the side dam 2.2, but in this case, because the molten metal surface is narrow, the molten metal level fluctuates widely (and this causes slab surface defects (double skin). , swelling, hot water wrinkles).

The present invention is proposed to improve the above-mentioned drawbacks of the conventional apparatus, and an object of the present invention is to provide an apparatus that can stably manufacture and supply high-quality thin plates.

In conventional equipment, two water-cooled rolls of the same diameter are installed horizontally opposite each other, whereas in the present invention, a water-cooled roll (small diameter roll) is placed diagonally above a water-cooled roll with potash (large diameter roll). Because of this, the molten metal head is low (
molten metal static pressure is small) bulging phenomenon of slab does not occur.

Furthermore, since one of the water-cooled rolls has a small diameter, a slab with a good shape can be obtained with low rolling reaction force, and the roll structure is relatively simple.

Hereinafter, a specific example of the present invention will be explained in detail based on FIG. 2. FIG. 2 shows an outline of the continuous casting apparatus of the present invention. This device consists of a water-cooled roll 11 (large-diameter roll) with a caliber 12, a water-cooled roll 13 (small-diameter roll) provided diagonally above this roll with a gap corresponding to the thickness of the plate to be cast, and both water-cooled rolls 11. .1 and the space surrounded by the caliber 12 (a side dam 14 for storing the molten metal 15, a pouring nozzle 16 and a tundish 17 for injecting the molten metal 15 into the side dam 14, and a thin plate 18 that has been cast and rolled). The main components include a knife edge 19 that separates from the water-cooled roll 11 and supports the thin plate, a guide roll 10 that guides the thin plate 18, and a pinch roll 20 that transports the thin plate 18.

The two water-cooled rolls 11 and 13 are driven to rotate in opposite directions (arrow directions) K by a drive device (not shown). The water-cooled rolls 11 and 13 are made of copper, copper alloy, or steel, and have a built-in water-cooling mechanism. It is a large diameter roll. Further, the diameter of the water-cooled roll 16 installed obliquely above the water-cooled roll 11 is approximately A of the diameter of the water-cooled roll 11. Side dam 14 is made of a material with excellent fire resistance and heat resistance.
For example, it is made of ceramics, etc., as shown in Figure 2.
The top of the water-cooled roll 110 and the inside of the caliber 12 are in contact with the water-cooled roll 13, and are pressed against the roll etc. via a lubricating and sealing material in order to prevent the molten metal 15 from leaking to the outside. Molten metal 15 is continuously and quantitatively supplied from tundish 17 through pouring nozzle 16 into the space formed by side dam 14 and both water-cooled rolls 11.13. The sealing of the molten metal 15 on the side is performed by the side dam 14 up to the P line (the lower end line of the site 9 dam), and by the caliber 12 from the P line onward. Water-cooled roll 11,1
The solidified shells 9,9' formed in contact with the rollers 3 are rolled to form a thin plate 18, which is then separated from the water-cooled roll 11 by a knife 19. In addition, the pinch rolls 20 are driven in synchronization with the water-cooled rolls 11.13 to transport the sheet 18 to the next process.

The present invention has the following effects (advantages).

(1) Since the molten metal head is low and the molten metal static pressure is small, bulging does not occur. Therefore, the internal quality of the slab (internal cracks and segregation are unlikely to occur) is good, and the slab shape is good.

(The upper roll 21 (water-cooled roll 16) has a relatively small diameter, so the rolling reaction force is small. Therefore, it is easy to maintain the accuracy of the roll gap and the slab shape is good. Also, the roll structure is compared It is simple and easy to design and manufacture.

(3) Because the molten metal surface is wide, fluctuations in the molten metal surface are small, and slab surface defects (double film, slag, molten metal spots) do not occur.

(41 Since the upper roll (water-cooled roll 13) has a small diameter, the knife 19 enters deeply and supports the slab at an early stage, so that bulging does not occur.

As described above, a thin plate having a desired thickness and good properties can be stably supplied.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view of a conventional continuous casting apparatus, and FIG. 2 is a schematic vertical cross-sectional view of an apparatus according to an embodiment of the present invention. In FIG. 2, 11: large-diameter water-cooled roll with caliber, 13: small-diameter water-cooled roll, 16: nozzle, 17: tundish, 19: knife. Sub-agent Patent attorney Akira Ito (2 others)

Claims (1)

[Claims] Iron or metal is placed in a molten metal reservoir formed by two water-cooled rolls rotating in different directions, separated by a gap equivalent to the thickness of the metal strip to be cast, and a side dam covering the side ends of the pair of rolls. In a continuous casting device in which molten non-ferrous metal is poured and a solidified shell formed by contacting the surface of a water-cooled roll is rolled and integrated into a strip, one of the water-cooled rolls is a large-diameter roll with a caliber, and the other water-cooled roll is a large-diameter roll with a caliber. The roll is a small diameter roll,
A thin plate continuous casting apparatus characterized in that this is disposed diagonally above the large diameter roll.