JP2977316B2 - Continuous casting method and apparatus for thin cast slab - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a twin-drum continuous method and apparatus for continuously casting thin cast slabs.

[0002]

2. Description of the Related Art A twin-drum system has been developed as one of the methods for continuously producing thin metal slabs. The apparatus will be described with reference to FIG.
And a pair of side weirs 2 and 2 disposed in pressure contact with the end face 2 thereof by a pressing device (not shown) to form a pool sump u, and the molten metal stored in the pool sump u is cooled by a cooling drum. The thin cast slab S is manufactured by rapid solidification by the rotation of 1,1.

In such a method, the side weirs are pressed against both end surfaces of a pair of cooling drums to seal the molten metal in the sump portion so as not to leak outside. In this sealing portion, the cooling drums are opposed to each other. It is important to close the contact surface because the end face of the cooling drum and the side weir are sliding at a relative speed, and maintain a preferable sealing surface depending on the abrasion state of both contact surfaces. In some cases, it will not be possible.

In the prior art, for example, Japanese Patent Application Laid-Open No. 63-248547 discloses a method in which a solid lubricant is applied to both end surfaces of the drum to reduce wear on the seal surface and prevent hot water on the seal surface. ing. Further, in this publication, as an example of supplying a liquid lubricant, a method is disclosed in which a seepage opening is provided in a side weir and rape oil is supplied from the seepage outlet via a supply hose.

[0005]

Originally, the pressure of the side weir in such a casting apparatus is adjusted by pressing means on both end faces of the drum in order to secure a sealing surface pressure at which no hot water is generated. In the case of a lubricant, the lubricant adhering to the drum end face is almost scraped off when it comes into contact with the side weir and cannot be used for lubrication, and the lubricant that has entered the gap between the drum end face and the side weir is the powder or granule. Since the amount was insufficient, the seal film thickness could not be ensured, so that the hot water could not be avoided.

Further, in the case of the above-mentioned liquid lubricant, there is a possibility that the seepage opening for supplying the lubricant is blocked by the end face of the drum and the lubricant is not supplied, so that breakout due to hot water may occur.

An object of the present invention is to provide a lubricating means which can maintain a lubricated state at all times by using a fluid lubricant.

[0008]

That is, a feature of the present invention is that a lubricating fluid is filled in a liquid storage space inside a side weir arranged in pressure contact with an end face of a cooling drum, and the lubricating fluid is provided to face the end face of the drum. In addition, the internal pressure of the lubricating fluid in the seal portion opening space communicating with the liquid storage space is increased, and thus the casting is performed while filling the press-contact gap between the end face of the cooling drum and the side weir with the lubricating fluid. Hereinafter, the present invention will be described in detail.

[0009]

The liquid storage space provided inside the side weir is filled with the lubricant in a molten state so as to have a preferable static pressure, so that an appropriate amount reaches the seal portion opening space via the respective supply liquid passages and the throttle portion. And accumulate. Since the opening space has an inclined surface that gradually reduces the gap between the opening space and the end surface in the direction in which the drum end surface moves, an internal pressure based on a wedge effect is generated in the lubricating fluid sandwiched between the opening space and the drum end surface. Then, a fluid lubrication state in which the drum end face and the side weir are separated from each other is entered, and the molten lubricant carried on the drum end face sufficiently fills the press contact gap between the side weir and the drum end face to maintain the lubrication state.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view of the apparatus of the present invention, in which a pair of side dams 4 and 4 are arranged on a pair of cooling drums 1 and 1 to form a pool basin u. A molten lubricant supply hole 6 is provided, which branches into a supply liquid passage 9.
Are provided in a desired number. The end of the supply liquid passage 9 opens to the drum end face 2 and communicates with the seal opening space 11. FIG. 2 is a sectional view taken along line AA of FIG. 1 and shows a connection structure of the supply hole 6, the supply liquid path 9, the throttle unit 10, and the opening space 11. The supply hole 6 forms a liquid storage space 8, and the throttle portion 10 limits the lubrication flow rate to an appropriate amount. FIG. 3 is an enlarged view of the connecting portion. An inclined surface 12 is formed so as to be connected to the opening end of the diaphragm unit 10. The inclined surface 12 is continuous with the contact surface 13 so as to gradually reduce the gap along the moving direction (arrow) of the end surface 2 of the cooling drum 1 and has a width not exceeding the width of the drum end surface 2. I have. Therefore, when the drum end face 2 and the contact surface 13 of the side weir 4 are in pressure contact with each other as shown in FIG. 4, the seal opening space 11 formed by the inclined face 12 communicates with the outside through the drum end face 2. It does not have a structure.

The position of the supply port 7 of the molten lubricant J is set as high as possible above the liquid storage space 8 in order to obtain a head of the molten lubricant J in the liquid storage space 8. Seal opening space 1
One alternative embodiment is shown in FIGS.

FIGS. 5 and 6 show examples in which a porous member 14 is buried in each opening space 11-1 of the throttle unit 10, and FIGS. The porous member 15 is buried in an opening space 11-2 common to the ends.

In such an apparatus, a fusible lubricant such as a vitreous agent, a molten salt agent, or the like is supplied to the lubricant supply port 7 in a solid state such as a granular material or a chip or in a molten state.
The reservoir space 8 is filled via the supply hole 6. Since the inside of the side weir 4 is normally maintained at a temperature of 1000 ° C. or higher by preheating or heating with a molten metal, the filled lubricant is always accumulated in the liquid storage space 8 in a molten state. The height of the accumulated liquid level is a head height that can secure a static pressure enough to overcome the molten metal pressure in the seal opening space 11.

As a result, the seal opening space 11 is filled with the liquid lubricant, an internal pressure is generated, and a fluid lubrication state in which the end face of the drum is separated from the side weir is obtained. A part of the liquid lubricant in the opening space 11 adheres to the drum end surface of the press contact portion that is rotating and sliding in such a state. When the cooling drum slides downward at a relative speed to the side weir in this manner, the liquid lubricant carried on the end face of the drum sufficiently fills the pressure gap between the side weir and the end face of the drum.

When the porous material is buried in the opening of the seal portion, the porous material is filled with the liquid lubricant and oozes out over a wide range, so that clogging does not occur and the supply of the lubricant is not stopped.

[0016]

As described above, according to the present invention, the lubricant in the molten state can be always supplied to the pressing surface between the drum end surface and the side weir forming the molten metal seal portion. By reducing the abrasion of the side weir and the end face of the drum and preventing the leakage of hot water from the pressure contact surface,
Stable long-time casting becomes possible.

[Brief description of the drawings]

FIG. 1 is a side view of the device of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partially enlarged view of FIG. 2;

FIG. 4 is a left side view of the side weir of FIG. 3;

FIG. 5 is a partial sectional view of another embodiment of the device of the present invention.

FIG. 6 is a left side view of FIG. 5;

FIG. 7 is a partial sectional view of another embodiment of the device of the present invention.

FIG. 8 is a left side view of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cooling drum 2 ... Drum end face 3 ... Drum shaft 4 ... Side weir 5 ... Pressing device 6 ... Supply hole 7 ... Supply port 8 ... Liquid storage space 9 ... Supply liquid passage 10 ... Narrowing part 11 ... Sealing part opening space 13 ... contact surfaces 14, 15 ... porous member S ... slab J ... lubricant u ... pool

Continuation of the front page (56) References JP-A-4-81250 (JP, A) JP-A-2-29749 (JP, A) JP-A-61-154738 (JP, A) (58) Fields studied (Int .Cl. ⁶ , DB name) B22D 11/06 330

Claims (4)

(57) [Claims] When a thin-walled slab is cast by a twin-drum continuous caster, a lubricating fluid is filled into a liquid storage space inside a side weir placed in pressure contact with an end face of a cooling drum, and the lubricating fluid is used to fill the end face of the drum. And the internal pressure of the lubricating fluid in the seal opening space communicating with the liquid storage space is increased, so that the lubricating fluid is filled in the press-contact gap between the end face of the cooling drum and the side weir. A continuous casting method for thin cast pieces, wherein casting is performed while performing casting. 2. A device for continuously casting thin cast slabs by a twin-drum continuous caster, wherein a lubricant supply hole is provided inside a side weir in pressure contact with an end face of the cooling drum to constitute a liquid storage space. A throttle portion that opens to face the end surface of the cooling drum is provided at an end of a supply liquid channel that branches off from the supply hole channel, and a seal portion opening space is further provided at an opening portion of the throttle portion. Continuous slab casting device. 3. The apparatus according to claim 2, wherein a porous member is buried in an opening space of the seal portion of the throttle portion. 4. The apparatus according to claim 2, wherein an opening end of the throttle section is communicated, and a porous member is buried in the communicated opening space.