JPS58188544A - Continuous casting device of metallic plate - Google Patents

Abstract

PURPOSE:To enable the continuous casting of a cast plate having good surface and internal quality by providing a vessel for molten metal, a molten metal well, and a spout for conducting the molten metal from the former to the latter and decreasing the fluctuation in the level of the molten metal surface in the molten metal wall. CONSTITUTION:A titled device consists of a pair of cooling rolls 1 which have mutually the same length and the same diameter, are horizontal and parallel in axial line and are in proximity to each other, a driving means for driving the rolls 1, a gate 6 provided to prevent the leakage of molten metal 9, a vessel 8 for molten metal, and a horizontal spout for conducting the metal 9 in the vessel 8 into a molten metal well 7. Said gate 6 is provided in proximity or contact with both axial ends on the respective outside circumferences of the rolls 1, and forms the well 7 cooperatively with the upper half parts on the outside circumferential surfaces of the rolls 1. The fluctuation in the level of the molten metal surface in the well 7 is decreased by the abovelmentioned device and a cast plate 9' having good surface and internal quality is obtained continuously.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a continuous metal plate casting apparatus that can continuously cast metal plates with sound surfaces and internal properties from molten metal such as molten steel.

For example, the following methods are conventionally known as methods for directly and continuously casting metal plates from molten metal.

(1) Twin roll system without weir: A pair of cooling rolls are installed so that their axes are horizontal and parallel to each other. Molten metal is ejected from a slit nozzle arranged parallel to the axial direction of both cooling rolls toward a portion where the outer peripheral surfaces of both cooling rolls are close to each other, and this is then sprayed onto the outer peripheral surfaces of both cooling rolls. The solidified shells thus obtained on the outer peripheral surfaces of both cooling rolls are pressed against each other by both cooling rolls.
The cast plate is continuously taken out from the roll gap between both cooling rolls.

(2) Fixed weir system: A pair of cooling rolls that have the same length and diameter, their axes are horizontal and parallel to each other, and are close to each other,
In order to prevent molten metal from leaking, a substantially cylindrical weir formed near or in contact with the upper end and both ends of the outer peripheral surface of each of the pair of cooling rolls is used to connect the pair of cooling rolls to each other. The molten metal injected into the base is brought into contact with the outer circumferential surfaces of both cooling rolls rotating in opposite directions and solidified, and the molten metal injected into the base is solidified from the roll gap between the two rotating cooling rolls. Remove the cast plate.

However, in the method (1) above, since the contact length between the outer circumferential surface of the cooling roll and the molten metal is short, metals such as aluminum and copper, which have a low melting point and high thermal conductivity, are used. Only metals that solidify in a very short time can be properly cast. Therefore, it is difficult to cast a metal plate made of a high melting point metal such as steel by the method (1) above.

The method (2) above has the following problems.

In other words, the so-called constant gap method, in which the roll gap is fixed, and the so-called constant gap method, in which the roll gap is fixed, and the roll gap method, in which the cast plate passing through the roll gap is held down at a constant pressure by the pair of cooling rolls, are used. There is a so-called constant pressure method that allows changing the pressure. However, when the constant pressure method is applied, the axis of the cooling roll moves horizontally, creating a gap between the weir and the outer circumferential surface of the cooling roll that exceeds the limit that does not substantially prevent molten metal from leaking. Molten metal poured into the base leaks and becomes a trench.

Therefore, this invention was made to solve the above-mentioned problems, and consists of a pair of cooling rolls that have the same length and the same diameter, whose axes are horizontal and parallel to each other, and which are close to each other. , a drive means for rotating the pair of cooling rolls at the same circumferential speed in opposite directions; and driving means for rotating the pair of cooling rolls in opposite directions at the same circumferential speed, and driving means that is close to or in contact with both axial ends of the outer circumferential surface of each of the pair of cooling rolls to prevent leakage of molten metal. a pair of weirs forming a molten metal reservoir in cooperation with the upper half of the outer circumferential surface of the pair of cooling rolls; a molten metal tank; At least 1
and a substantially horizontal gutter, the other end of which is fixed to the molten metal tank, for guiding the molten metal in the molten metal tank into the molten metal reservoir. .

Fig. 1 is a schematic plan view showing one aspect of the continuous casting apparatus for metal sheets according to the present invention, Fig. 2 is a schematic longitudinal sectional front view of the apparatus, and Fig. 3 shows a part of the apparatus. A schematic perspective view, and FIG. 4 is a sectional view of the cooling roll.

In the figure, reference numerals 1 denote a pair of cooling rolls that are close to each other, and the pair of cooling rolls 1 have the same length and diameter, and their axes are horizontal and parallel to each other. The pair of cooling rolls 1 are rotated by a driving means (not shown) in mutually opposite directions, that is, in a direction in which their respective outer peripheral surfaces descend in the portion where their respective outer peripheral surfaces are closest, at the same circumferential speed.

As shown in FIG. 4, the peripheral wall 1a of each of the pair of cooling rolls 1 is made of two metals (for example, copper or copper alloy) with high thermal conductivity, and a spiral is formed in the circumferential direction. A continuous coolant passage 2 is formed. A cooling medium such as water or a high boiling point heat medium is supplied from one end of the shaft (hollow shaft, but the middle is closed) 3 of the cooling roll 1.
It passes through the supply vibe 4 and is supplied to one end of the coolant passage 2 located at one end of the peripheral wall 1a, and then passes through it and reaches the other end of the cooling medium passage 2 located at the other end of the peripheral wall 1a. , from there it passes through a discharge pipe 5 and is discharged to the other end of the shaft 3. Therefore, the molten metal that has come into contact with the outer peripheral surface of the cooling roll 1 is solidified by exchanging heat with the cooling medium supplied into the cooling medium passage 2 of the peripheral wall 1a (cooled).

6 is at both ends in the axial direction of the outer circumferential surface of the pair of cooling rolls 1,
They are a pair of weirs that are close to each other to prevent molten metal from leaking, and each of the pair of weirs 6 is fixed to support means (not shown). In this way, the molten metal reservoir 7 is formed by the upper half of the outer peripheral surface of each of the pair of cooling rolls 1 and the pair of weirs 6. It is a molten metal tank having a sufficiently larger volume than the molten metal reservoir 7 for storing the molten metal 9, and 10 is a gutter arranged substantially horizontally, and one end of the gutter 10 is connected to the molten metal tank 8. The other end of the gutter 10 is fixed to the upper part of the gutter 10 so as to communicate with the inside thereof.
It is fixed to one of the weirs 6 so as to communicate with the molten metal reservoir 7.

Therefore, the molten metal 9 contained in the molten metal tank 8 is supplied into the molten metal reservoir 7 through the gutter 10.

Reference numeral 11 denotes a partition provided in the upper part of the molten metal tank 8 to prevent pollution from the fixed part of the gutter 10. This partition 11 allows the inside of the molten metal tank 8, which does not include the fixed part of the gutter 10, to
Molten metal 9 is supplied from the molten metal supply means, and
A refractory 12 having a predetermined volume enters into the molten metal 9 thus supplied in a manner that allows the amount of elevation to be adjusted.

With the above configuration, when the molten metal 9 is supplied from the molten metal supply means into the molten metal tank 8 with the flow rate controlled to be a predetermined flow rate, the molten metal 9 accommodated in the molten metal tank 8 is , and into the molten metal reservoir 7 through the gutter 1o. The molten metal 9 in the molten metal reservoir 7 is in contact with the outer peripheral surface of each of a pair of cooling rolls rotating in opposite directions at the same peripheral speed, and the molten metal 9 in contact with the outer peripheral surface is , solidified, and thus obtained on the outer circumferential surface of each of the pair of cooling rolls 1.As the cooling rolls 1 rotate, the pair of solidified shells are They are pressed together by the cooling rolls 1 and taken out from the roll gap as a cast plate 9'. At this time, since the volume of the molten metal tank 8 is sufficiently larger than the volume of the molten metal reservoir 7, even if the supply flow rate of the molten metal 9 from the molten metal supply means fluctuates,
Fluctuations in the height of the molten metal 9 in the molten metal reservoir 7 are small, and therefore the molten metal 9 on the outer peripheral surface of the cooling roll 1 is small.
A cast plate 9' having a stable solidification thickness and good internal quality is obtained (note that the molten metal 9 accommodated in the molten metal tank 8
By adjusting the amount of penetration of the refractory 12 into the
It is possible to suppress minute fluctuations in the level of the molten metal in the molten metal tank 8 (molten metal reservoir 7). Further, since the part (molten metal tank 8) to which the molten metal 9 is directly supplied from the molten metal supply means and the molten metal reservoir 7 are separated and connected by the gutter 10, the molten metal The surface roughness of the molten metal 9 in the reservoir 7 is extremely small. this is,
The partition 11 can further reduce the size. Therefore, a cast plate 9' with a good surface can be obtained.

As explained above, according to the present invention, a metal plate having a sound surface and internal quality can be continuously cast in an extremely stable manner.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing one aspect of the continuous casting apparatus for metal plates according to the present invention, FIG. 2 is a schematic longitudinal sectional front view of the same apparatus, and FIG. 3 is a schematic perspective view showing a part of the same apparatus. FIG. 4 is a sectional view of the cooling roll. 1... Cooling low nope 61. , Weir, 8... Molten metal tank, 10... Gutter. Applicant Nippon Kokan Co., Ltd. Agent Keitabe Tsutsumi and 1 other person Figure 1 Figure 3 Figure 4

Claims (1)

[Scope of Claims] A pair of cooling rolls that have the same length and the same diameter, whose axes are horizontal and parallel to each other, and are close to each other, and the pair of cooling rolls are moved in opposite directions at the same circumferential speed. a drive means for rotating the drum, and an F half portion of the outer circumferential surface of the pair of cooling rolls that is close to or in contact with both ends in the axial direction of the outer circumferential surface of each of the pair of cooling rolls to prevent molten metal from leaking. a pair of weirs that cooperate to form a molten metal reservoir; a molten metal tank; and at least one of the pair of weirs having one end connected to the molten metal tank.
and a substantially horizontal gutter having the other end fixed to the trough for guiding molten metal in the molten metal tank into the molten metal reservoir.