JPH09206892A - Side weir of apparatus for continuous production of sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to drastically reduce a casting cost by inserting parting materials between base members and ceramic members. SOLUTION: The twin-drum type apparatus for production of sheets is constituted by providing both end faces of a pair of cooling drums with side weirs, thereby forming a casting mold. When an example of the construction of such side gates is shown, monolithic refractories are housed into side weir cases and the base members 9 are implanted into these monolithic refractories. After the base members 9 are provided thereon with the parting materials 11, the ceramic plates 10 are adhered and fixed by adhesives 12. The parting materials 11 may not always be required to be disposed over the entire surface. An equally good practice is to bore the film-like parting materials 11 with holes at several points so that the adhesives 12 partly come into direct contact with the base members 9. As a result, the easy and rapid intermediate repair of the side weirs is made possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side weir of a twin drum type continuous thin plate casting apparatus.

[0002]

2. Description of the Related Art Recently, attention has been focused on a method for directly producing a thin plate having a thickness of about several mm close to a final shape from a molten metal such as molten steel. According to this continuous casting method, it is not necessary to carry out a multi-step hot rolling process as in the prior art, and rolling to a final shape may be light, so that the process and equipment can be simplified.

As one of such continuous casting methods, there is a twin drum method (a method of continuously casting with a pair of cooling drums) (JP-A-60-137562). FIG.
FIG. 4 is a perspective view for explaining the outline of this twin drum method. In this system, as shown in this figure, a pair of cooling drums 1a and 1b that rotate in opposite directions are horizontally arranged, and the cooling drums 1a and 1b and the side dams 2a and 2b are arranged.
The basin 3 is formed in the recess defined by b. Molten metal is poured into the pool 3 from a container such as a tundish via a pouring nozzle. The molten metal 4 contained in the molten metal pool 3 is cooled at the portions in contact with the cooling drums 1a and 1b and solidifies to form a solidified shell.

This solidified shell is composed of cooling drums 1a and 1b.
Along with the rotation of the cooling drums 1, the pair of cooling drums 1a and 1b move to the position closest to each other, that is, the so-called drum gap portion 6 while increasing its thickness,
The solidified shells formed on the surfaces of a and 1b are pressed together here to form the desired metal ribbon 5. In addition, 15 is an end surface of the cooling drum, and 16 is a sliding surface.

As can be seen in Japanese Utility Model Laid-Open No. 63-90548 and its specification, in such a thin plate continuous casting apparatus, the side dams 2a and 2b are generally heat insulating materials housed in a side dam case, The base member is planted in the material, and the ceramic plate is planted on the surface of the base member corresponding to the cooling drum.

At the time of casting, the side dam is pressed against the end surface of the cooling drum, and the ceramic plate is worn on the sliding surface of the cooling drum to eliminate the gap between the end surface of the cooling drum and the side dam to prevent leakage of molten steel. . In addition, JP-A-61
As disclosed in Japanese Patent Publication No. 266160, the side dam is generally subjected to vibration, which promotes wear of the ceramic plate.

Therefore, the continuous casting amount of the thin plate by the thin plate continuous casting apparatus is determined by the wear rate of the side dam ceramic plate due to the sliding on the end surface of the cooling drum, and when the wear of the ceramic plate reaches a certain amount, the entire side dam is replaced. Becomes However, in order to reduce the casting cost, it is desired to realize an intermediate repair method in which only the ceramic plate that is worn and worn is replaced and the other parts are reused.

[0008]

However, since the base member and the ceramic plate are usually bonded with an adhesive, it is not easy to peel the ceramic plate from the base member, and when the base member is peeled, the base member is bonded. The surface is damaged, and the adhesive remaining on the surface of the base member has to be removed, so that the burden on the intermediate repair is large. An object of the present invention is to solve such problems and to provide a side weir capable of easily performing an intermediate repair.

[0009]

The present invention relates to a side weir of a twin-drum type thin plate continuous casting apparatus in which a side weir is pressed against both end faces of a pair of cooling drums whose axes are arranged in parallel and horizontally to form a mold. A heat insulating amorphous refractory housed in the side dam case, a base member planted in the irregular refractory, and a base member planted in the base member so as to slide on the end surface of the cooling drum. In the side weir composed of the ceramic plate, the release material is inserted into the entire surface or a part of the space between the base member and the ceramic plate.

If there is a gap between the side surface of the ceramic plate and the release material, a castable is embedded in the gap, and at that time, depending on the difference in coefficient of thermal expansion between the base member and the ceramic plate. Then, the material of the castable to be embedded is selected so as to absorb the thermal expansion of the ceramics plate and restrain the ceramics plate by the compressive force.

In the side dam of the present invention, since the ceramic plate is adhered to the mold release material with the mold release material inserted between the base member and the ceramic plate, the ceramic plate can be easily peeled off from the base member after completion of continuous casting. In addition, the surface of the base member can be kept smooth even after the ceramic plate is peeled off. Therefore, the intermediate repair can be easily repeated.

Further, a certain gap is provided between the side surface of the ceramic plate and the release material, and a castable material of an appropriate material selected according to the difference in coefficient of thermal expansion between the base member and the ceramic plate is embedded therein. If the castable absorbs the thermal expansion of the ceramic plate and the ceramic plate is constrained by the compressive force, it is possible to prevent the ceramic plate from cracking due to thermal stress and the sliding of the ceramic plate during use. .

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 3 is a front view showing an example of the structure of the side weir. That is, the outside of the side dam 2a is covered with the side dam case 7, and the surface in contact with the end surface 15 of the cooling drum 1b is composed of the heat insulating material 8, the base member 9, and the ceramic plate 10 planted thereon. . Among these, the ceramic plate 10 is planted along the surface that slides on the cooling drum sliding surface 16, that is, the wear surface 20.

FIG. 1 is a sectional view showing an example of the structure of the side dam of the present invention. That is, after the release material 11 is provided on the base member 9, the ceramic plate 10 is adhered and fixed by the adhesive 12. The release material 11 does not necessarily have to be provided on the entire surface as shown in FIG. Alternatively, holes may be formed at several positions in the film-shaped release material 11 so that a part of the adhesive 12 directly contacts the base member 9.
However, the surface of the base member 9 is required to be smooth at the time of intermediate repair, and if the adhesive 12 still attached on the base member 9 remains, it is necessary to remove the adhesive, which results in a work cost. Since it becomes high, it is preferable that the contact area of the adhesive 12 with the base member 9 is as small as possible.

FIG. 2 is a sectional view showing another example of the structure of the side dam of the present invention. In this case, the ceramic plate 10
A constant gap is provided between the side surface 13 of the mold and the release agent 11, and the castable 14 is embedded therein, so that the ceramic plate 10 can be restrained while absorbing the thermal expansion of the ceramic plate 10 during preheating and casting. I have to. The material of the castable 14 used at that time is selected according to the difference in the coefficient of thermal expansion between the base member 9 and the ceramic plate 10 at the operating temperature so that such thermal expansion can be absorbed and the ceramic plate 10 can be restrained. There is a need to.

[0016]

EXAMPLES Next, details of the results of carrying out the work of “casting → intermediate repair → recasting” using the thin plate continuous casting apparatus as described above and the side weir whose structure is shown in detail in FIG. Describe.

The material of the water cooling drum used is SUS304,
The base material of the side dam is high alumina brick, the material of the ceramic plate is BN: 50%, AlN: 50%, the release agent is oil paper, and the surface pressure of the side dam pressed against the sliding surface of the water cooling drum is 3 kg / cm ^2. The sliding speed of the ceramic member with respect to the sliding surface of the water cooling drum was 60 m / min. First, when the side weir was preheated, the ceramic plate did not peel off or deteriorated due to the use of the mold release material, and the temperature rise was good. When preheating was completed, casting of SUS304 steel was started, and it was possible to smoothly perform casting without operating trouble such as leakage of molten metal.

At the stage of casting 500 tons, the wear amount of the ceramic plate reached the wear limit value, so casting was stopped.
When the side dam was cooled to near normal temperature, the ceramic plate was peeled off from the base member with a chisel, and the carbonized release material clearly separated the base member and the ceramic plate to which the adhesive was attached, All the ceramic plates could be peeled off from the base member easily and in a short time. Further, the release agent remaining on the base member could be removed by brushing, and thus the surface smoothness was also good.

A new ceramic plate was again bonded to the side member on the base member via oil paper, and the casting test was conducted again. It could be used without trouble both during preheating and during casting. The total cost of the side weirs when casting was performed twice could be reduced to 65% of the conventional value.

Then, using a vinyl film as a release material and a fused siliceous castable material,
A side weir as shown in detail in FIG. 2 was used under the same conditions as above. As a result, there were no problems during preheating and during casting, and intermediate repair and recasting could be carried out without problems. Regarding the release material, the method of placing or applying oil paper, vinyl film, grease, etc. on the base member is good, but the method of vinyl coating on the surface of the base member is also effective. To do.

[0021]

As described above, when the side weir of the present invention is used, the cerax plate can be easily peeled from the base member after being used once, and the surface of the base member can be kept smooth, so that the surface can be easily maintained. Moreover, the intermediate repair of the side weir can be performed quickly, and a significant reduction in casting cost can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing an example of a side dam structure of the present invention.

FIG. 2 is a cross-sectional explanatory view showing another example of the side dam structure of the present invention.

FIG. 3 is a front view schematically showing a side weir used in a twin drum continuous casting method.

FIG. 4 is a perspective view showing an outline of a twin drum method.

[Explanation of symbols]

1a, 1b: cooling drum, 2a, 2b: side weir,
3: Hot water pool, 4: Molten metal, 5: Metal ribbon,
6: Drum gap part, 7: Side weir case, 8:
Heat insulating agent, 9: base member, 10: ceramics plate,
11: Mold release material, 12: Adhesive material, 13: Ceramic plate side surface, 14: Castable, 15: Cooling drum end surface, 16: Cooling drum sliding surface, 20: Ceramic plate worn surface.

Claims (3)

[Claims] 1. A side weir of a twin-drum type thin plate continuous casting apparatus in which a side weir is pressed against both end faces of a pair of cooling drums whose axes are arranged in parallel and horizontally to form a mold, and which is housed in a side weir case. An irregular shaped refractory, a base member planted in the irregular shaped refractory, and a ceramics plate planted in the base member so as to slide on the end surface of the cooling drum. A side dam of a thin plate continuous casting apparatus, wherein a release material is inserted into the entire surface or a part of the space between the base member and the ceramic plate. 2. A side weir of a thin plate continuous casting apparatus according to claim 1, wherein castables are embedded in a gap existing between the side surface of the ceramic plate and the release material. 3. Absorbing the thermal expansion of the ceramic plate, which is selected according to the difference in thermal expansion coefficient between the base member and the ceramic plate,
3. A side weir of a thin plate continuous casting apparatus according to claim 2, wherein a castable material made of a material capable of restraining the ceramic plate by a compressive force is embedded.