JPH02241646A - Sealing method, sealing material and sealing device for molten steel in twin roll type continuous casting equipment - Google Patents

Abstract

PURPOSE:To prevent invasion of molten steel and solidified shell into a gap by supplying a sealing material at gap formed between roll end face and side weir near the outer circumference of mold roll. CONSTITUTION:In bending part 5a, the discharging holes 11 for supplying the sealing material into the gap (a) from each divided supplying pipe passage 10 are formed, for example, three holes 11 are formed, respectively. At the time of casting, the sealing material is supplied into the gap (a) between the roll end face 1a and the weir body 4 with a seal supplying device to prevent the invasion of the molten steel and the solidified shell into the gap (a). Further, the sealing material temp. is raised by receiving the heat from the molten steel, but as the generated carbide, etc., has lubricating function, wear of the weir body 4 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for sealing molten steel in twin-roll continuous casting equipment, a sealing material, and a sealing device.

BACKGROUND ART As equipment for continuous casting of thin steel sheets, there is a twin-roll type equipment that uses a pair of mold rolls (hereinafter simply referred to as rolls) to pull out a slab from between the two rolls. In this twin-roll type continuous casting equipment, as shown in FIG.
02, side weirs 103 are arranged at both ends of each roll 101. Conventionally, in order to prevent leakage of molten steel, this side weir 103 was installed on the roll 1.
It was being pressed with considerable force by the 01 side.

Problems to be Solved by the Invention However, according to the above-mentioned conventional configuration, as shown in FIG. Also roll 1
There was a problem that the corner portion of 01 was rounded, which adversely affected the sealing performance. In addition, as shown in FIG. 8, a gap is inevitably created between the two due to the influence of heat, and molten steel enters this gap, creating burrs 104 and causing deterioration of the shape of the slab, and the sliding part of the side weir 104. There was a problem in that it could cause destruction, causing casting to stop.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for sealing molten steel in twin-roll continuous casting equipment, a sealing material, and a sealing device that can solve the above-mentioned problems.

Means for Solving the Problems In order to solve the above problems, the method for sealing molten steel in twin roll continuous casting equipment of the present invention includes a pair of mold rolls, and two mold rolls arranged on both end faces of both mold rolls. A molten steel sealing method for preventing molten steel from entering between the mold rolls and a side weir forming a molten steel reservoir above the mold rolls, the method comprising: forming a molten steel seal between the roll end face near the outer periphery of each of the mold rolls and the side weir; This method supplies sealing material to the gap. Further, in the above sealing method, the sealing material is a powdered refractory material or a plastic powdered material mixed with an organic liquid and has fluidity. Furthermore, in order to resolve the above issues,
The molten steel sealing device in the twin-roll continuous casting equipment of the present invention is designed to remove gas generated from the sealing material supplied to the gap formed between the roll end face and the side weir near the outer periphery of each mold roll. porous member,
It is provided at a location opposite to the end face of the roll of the side weir.

Effect: According to the above sealing method, the sealing material is supplied to the gap formed between the roll end face and the side weir near the outer periphery of the mold roll during continuous casting.
Molten steel or solidified shells are prevented from entering the gaps. In addition, if a fluid material such as a powdered refractory material or a plastic powder mixed with an organic liquid is used as a sealing material, as the temperature rises, carbide with a lubricating function remains, causing wear on the weir body. At the same time, a part of it also enters the mechanical sliding area between the roll end face and the side weir, thereby preventing mutual wear. Further, since a porous member for releasing gas is provided at a location of the side weir facing the end face of the roll, no problem occurs even if gas is generated from the sealing material.

EXAMPLE Hereinafter, an example of the present invention will be explained based on FIGS. 1 to 5.

In Figures 1 to 3, reference numeral 1 denotes a pair of mold rolls (only one is shown in the drawings, hereinafter simply referred to as rolls) arranged parallel to each other, and a molten steel reservoir 2 is formed above between these rolls 1. Side weirs 3 for this purpose are arranged on both end faces of the roll 1. And each of these side weirs 3
The weir body 4 is made of a refractory material and has a substantially inverted trapezoidal shape, the support member 5 having an L-shaped cross section that supports the weir body 4 from the outside, and the support member 5 is pressed against the end face side of the roll 1. It is comprised of a suppression jack 6 for urging. A predetermined gap a (for example, in the range of 0.01 to 0-2 mm) is formed between the weir body 4 and the outer peripheral end surface 1a of the roll 1 (this part protrudes from the center on both sides). As shown, it is supported by the lower end bent portion 5a of the support member 5. Note that the adjustment of the gap a is performed by a push bolt 8 via a push piece 7 arranged between the weir body 4 and the support member 5. Further, the bent portion 5a of the support member 5 is made of metal (or may be made of ceramic having mechanical strength) and has an arc shape, and has a cooling water pipe 9 and a sealing material supply pipe inside. A channel 10 is formed. Furthermore, this sealing material supply pipe 1
For example, 0 is divided into three parts in the circumferential direction, and the bent part 5
For example, three discharge ports 11 are formed in the space a for supplying the sealing material to the gap a from each of the divided supply pipes 10a. Further, a sealing material supply device 12 is connected to each of the divided supply pipes 10a. This sealing material supply device 12 has a sealing material storage tank 13, a distributor 14 is interposed in the middle, and a connection connecting the storage tank 13 and the sealing material supply pipe 10, that is, each divided supply pipe 10a. a pipe 15, a variable displacement pump 16 interposed in the middle of the connecting pipe 15, and a pressurizing member made of a metal porous material interposed in the middle of the connecting pipe 15 between the distributor 14 and the pump 16; 117, this pressure member 17 and pump 16
and a control device 19 that adjusts the discharge amount and discharge pressure of the pump 16 via a pressure gauge 18 interposed in the connecting pipe 15 between the pump 16 and the pump 16. By the way, the sealing material used has a viscosity of ASTM 200 to 400, and is made by mixing, for example, a solid powder fireproof material (with a softening temperature of 800°C or higher) and an organic liquid. A material with good fluidity is used.

That is, the organic liquid contains a powdered refractory material with a particle size of about 1 to 20 μm, and the organic liquid contains
A substance that volatilizes to a small amount of char in the range of 20 to 700°C, such as rapeseed oil, is used. Further, as the powder refractory material, a carbonized compound, an aluminum oxide compound, or a nitrided compound (for example, BN) is used.

More specifically, as a solid powder refractory material, the particle size is 0.
．． SiO2 (fused silica) with a diameter of about 4 to 20 μm (average 1 to 2 μm) is used, and the kneading ratio of the solvent rapeseed oil and the powdered refractory material is 5 to 50% (for example, 25%) by weight.
), and by adjusting the material of the powder refractory material and the viscosity of the solvent, ASTM preparation 200-4 as mentioned above.
The liquid should be made into a liquid that can be pumped under pressure of about 0.00. Note that the solid powder refractory material is required not to melt at the temperature (maximum 800° C.) in the gap a.

By the way, the reason why the sealing material supply conduit 10 is divided into three parts is to prevent the discharge amount from varying among the discharge ports 11. In addition, the amount of sealing material consumed changes depending on the casting speed, that is, the consumption increases as the speed increases, and the amount of sealing material discharged as the roll 1 rotates also increases as it approaches the outlet of the slab. The respective discharge amounts can be adjusted, for example, by a distributor 15 depending on the divided supply pipe line 10a.

As described above, since the organic liquid has volatility, the roll 1 of the weir body 4 is used to discharge the volatilized gas.
At a location corresponding to the roll end surface 1a near the outer periphery,
A porous member 20 is arranged.

In the above configuration, during casting, the sealing material supply device 12 supplies the sealing material 21 to the gap a between the roll end surface 1a and the weir body 4 as shown in FIG. B is prevented from entering. In addition, the temperature of this sealing material 21 rises as it receives heat from the molten steel, but since carbides and the like that are generated with the rise in temperature have a lubricating function, wear of the weir body 4 is prevented.
Moreover, a part of it also enters the mechanical sliding area between the roll end surface 1a and the side weir 4, that is, the contact surface between the roll end surface 1a and the bending part 5a of the support member 5, forming a thin film that prevents each other from sliding. Wear is prevented. Furthermore, as the temperature rises, the powdered refractory material remains in the sealing material 21 and moves outward together with the solidified shell, so that the gap a is always replenished with new sealing material 21, making it reliable. A seal is performed.

Note that FIG. 5 shows the state of the sealing material 21. As shown in FIG.

In FIG. 5, 21a shows the remaining powder refractory material, 21b shows the sealing material in volatilization, and 21c shows the sealing material supplied from the outlet 11.

By the way, controlling the supply amount of the sealing material 21 is important.

That is, if the supply amount is large, the sealing material will enter the molten steel, and conversely, if the supply amount is small, the sealing effect will deteriorate. Therefore, in this example, the amount of sealing material supplied is controlled using the casting speed value as a coefficient, but since the amount of sealing material consumed varies depending on the temperature and the state of the solidified shell, it is necessary to The supply amount is controlled by the supply pressure via a pressure gauge 18 interposed in the middle of the connecting pipe 15. Note that the required supply pressure of the sealing material is a low pressure of about 0 to 0.2 kg/cJ, which is the static pressure of molten steel, and it is difficult to control the supply pressure.

For this reason, in the above configuration, the pressure that is generally easily controlled by the pressure member 17 interposed in the middle of the connecting pipe 15,
For example, the discharge pressure or discharge flow rate of the pump 16 is controlled by setting the pressure to 5 kg/cJ or more and measuring the pressure before that.

Note that the gas generated from the organic liquid of the sealing material is discharged to the outside from the porous member 20 disposed at the lower part of the weir body 4.

A specific example will be explained here.

500k molten steel equivalent to 5US304 (JIS standard)
70m at 30m/win (however, the slab width is 20m)
0 mm 1 slab thickness 4.5 ms) The results of casting are shown. However, the roll is water-cooled and its material is 13Cr-3.
It is Ni.

(2) In the case of the present invention, no wear occurred on the sliding parts of the side weir, that is, on the alumina-based porous member and the end face of the roll.

■In the case of the conventional example, abrasion of about 0.3 to 0.5 mm occurs at the sliding part of the side weir made of 5fiO3 with the end surface of the roll, and scratches with a depth of about 093■ are formed on the end surface of the roll. It was in need of revision.

By the way, in the above embodiment, the sealing material was explained as a mixture of a powdered fireproof material and an organic liquid, but for example, a mixture of a plastic powder material and an organic liquid may be used. carbide remains and the lubrication function improves.

Furthermore, in the above embodiments, the mechanical sliding portions of the roll and the side weir, that is, the roll end faces and the bent portions of the support member are slid. Alternatively, a gap may be provided over the entire surface.

Furthermore, in the above embodiment, the sealing material was supplied over almost the entire length of the sliding portion between the roll end face and the side weir, but for example, the sealing material was supplied only to the minimum necessary length range. You can do it like this. That is, the starting end of the supply of the sealing material to the gap a may be slightly above the level of the molten steel in the molten steel reservoir.

Furthermore, in the above embodiment, the sealing material supplied to the gap was not forcibly heated, but for example, a heating means was provided on the side weir side to forcibly heat the organic liquid solvent of the sealing material. It may also be allowed to volatilize.

Effects of the Invention As described above, according to the configuration of the present invention, the sealing material is supplied to the gap formed between the roll end face and the side weir near the outer periphery of the mold roll, so that molten steel and solidified shells are supplied to the gap. is prevented from entering. Additionally, if a fluid mixture of powdered refractory material or plastic powdered material with organic liquid is used as a sealing material, the rise in temperature will generate carbides that have a lubricating function, preventing wear on the weir body. Along with being
A part of it also enters the mechanical sliding area between the roll end face and the side weir to prevent mutual wear.

Further, since a porous member for releasing gas is provided at a location of the side weir facing the end face of the roll, no problem occurs even if gas is generated from the sealing material.

[Brief explanation of drawings]

Figures 1 to 5 show one embodiment of the present invention.
The figure is a side view of the main part of the side weir, Figure 2 is a sectional view taken along line I-I in Figure 1, Figure 3 is a view taken along the ■-■ arrow in Figure 2, and Figures 4 and 5 are the sealing material supply. 6 to 8 show a conventional example, and FIG. 6 is a schematic overall perspective view,
FIGS. 7 and 8 are sectional views of main parts during casting. 1... Roll, 2... Molten steel reservoir, 3... Side weir, 4... Weir body, 10... Seal material supply pipe line, 10a... Division supply pipe Channel, 11...Discharge port, 12...Seal material supply device, 16...Pump, 17...Pressure member, 18...Pressure gauge, 19
... Control device, 20 ... Porous member, 1 ... Sealing material.

Claims (1)

[Claims] 1. Molten steel that prevents molten steel from entering between a pair of mold rolls and side weirs that are arranged on both end faces of these mold rolls and form a molten steel reservoir above between both mold rolls. A sealing method for molten steel in a twin-roll continuous casting facility, characterized in that a sealing material is supplied to the gap formed between the roll end face and the side weir near the outer periphery of each of the mold rolls. . 2. The sealing material used in the method for sealing molten steel in twin-roll continuous casting equipment according to claim 1, characterized in that it has the fluidity of a powder refractory material or a plastic powder material mixed with an organic liquid. 3. In a twin roll type continuous casting equipment having a pair of mold rolls and side weirs arranged on both end faces of these mold rolls to form a molten steel reservoir above between both mold rolls, near the outer periphery of each of the mold rolls. A twin twin characterized in that a porous member for removing gas generated from the sealing material supplied to the gap formed between the roll end face and the side weir is provided at a location opposite to the roll end face of the side weir. Sealing device for roll type continuous casting equipment.