JP3025135B2 - Side dam for twin-drum continuous casting and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side weir used in twin-drum continuous casting and a method for producing the same.

[0002]

2. Description of the Related Art In continuous casting of wide and thin cast slabs using, for example, a twin-drum continuous casting apparatus generally known in the art, as shown in FIG. 2, a pair of rotating cooling drums Ra and Rb are provided. The molten metal e is supplied from the inside of the tundish through the inner nozzle a and the outer nozzle b into the moving mold formed by the side weirs Sa and Sb abutting on both end surfaces of the drum, and the molten metal e is supplied to the moving mold at a predetermined level. While forming the pool portion p, it is cooled by a cooling drum to form a solidified shell, and the solidified shell is pressed and integrated in a gap formed at the closest portion of the pair of cooling drums to form a wide thin cast slab c. I am getting it.

The side weirs Sa and Sb are indispensable for sealing the molten metal e (hatched portion) between the cooling drums Ra and Rb as shown in FIG. The side weir is, for example,
As disclosed in Japanese Patent No. 90548, the configuration is as shown in FIG.

That is, the side weir 1 comprises a frame plate 2 and a bottom plate 3
A heat insulating refractory material 5 in a side weir case 4 consisting of
It comprises a base member implanted in the refractory material, a heater 8 built in the base member, and a ceramic plate layer 7 implanted in the base member. The transfer mold is formed by directly contacting both end faces.

During casting, it is necessary to prevent the molten metal from leaking from between the side weir and the end face of the rotating cooling drum. For this reason, especially, the ceramic layer slides in close contact with the end face of the cooling drum. It is necessary to have a surface which has a shape that is sufficiently compatible with both end surfaces of the drum, and has an appropriate lubricity in terms of material.

At the start of casting, it is customary to preheat the side weir before starting the casting in order to prevent the adhesion of metal to the side weir and reduce the thermal shock to the side weir. In this case, in order to stabilize the continuous casting operation, while suppressing the thermal deformation of the side dam as much as possible,
It is necessary to make this thermal deformation reproducible.

This side weir is conceptually formed by connecting a base member having a Y-shaped groove for implanting a ceramic layer on the surface layer and having a heater insertion hole therein to a side weir case comprising a frame plate and a bottom plate. Arranged through a heat insulating mortar, poured an irregular-shaped refractory into the surrounding area, cured and dried, then arranged a ceramic plate of similar shape to this in the Y-shaped groove of the base member and bonded using an adhesive. It is obtained by polishing the surface of a ceramic plate, and has a rigid body attached to the back side of a metal case.

[0008] The side weir obtained in this manner uses an amorphous refractory or an adhesive containing water. If water remains, there is a risk of explosion or destruction at the time of preheating or contact with the molten metal. Therefore, curing and drying are required. In particular, there is a concern that the side weir is deformed irregularly due to the drying step or preheating before the start of casting, which impairs the shape characteristics and loses the suitability as a side weir.

[0009]

SUMMARY OF THE INVENTION The present invention prevents thermal deformation of each part of a side weir during drying of a side weir or preheating before casting, and suppresses thermal deformation of a side weir. An object of the present invention is to provide a side weir for twin-drum continuous casting capable of imparting reproducible thermal deformation to the weir and a method of manufacturing the same.

[0010]

According to a first aspect of the present invention, there is provided a metal case in which a water-cooled stiffener is fixed to a back surface, a Y-shaped groove provided in the metal case and having a built-in heater and for implanting a ceramic plate. For a twin-drum continuous casting, comprising: a base member having: a refractory filled around the base member, and a ceramic plate planted on the base member so as to slide on the end face of the cooling drum. At the side weir, between the side plate of the metal case and the refractory ,
A double-drum continuous casting side weir characterized by being loaded with a shrinkable heat insulating material.

According to a second aspect of the present invention, when a base member having a built-in heater and a Y-shaped groove for implanting a ceramic plate is disposed in a metal case having a water-cooled stiffener fixed to the back surface, a metal member is provided by using a position fixing member. After forming the expansion allowance between the case and the base member, loading the shrinkable heat insulating material and inserting the rod-shaped body into the heater insertion hole, pouring the metal case and the base member into a constrained state, pouring in an amorphous refractory, and curing. A cooling medium is supplied to the water-cooled stiffening body, and heated and dried at a temperature of 350 ° C. or more while cooling. After heating and drying, a ceramic plate is implanted in the Y-groove for implantation of the base member, and a rod-shaped body is formed. A method for manufacturing a double-drum continuous side weir for continuous casting, comprising inserting a heater into a heater insertion hole formed by the method and fixing the heater.

According to a third aspect of the present invention, when the ceramic plate is implanted in the implantable Y-shaped groove of the base member after the heating and drying, a space is provided between the implanted Y-shaped groove and the ceramic plate. A double-drum continuous casting side weir characterized by polishing the surface of the ceramic plate to a roughness of 10 S or less after solidifying and bonding, pouring an adhesive with the base member and the ceramic plate in a constrained state, and solidifying and bonding. It is a manufacturing method.

[0013]

In the side weir the present invention, the side of the metal casing
Since the shrinkable heat insulating material is loaded between the plate and the refractory having the base member implanted therein , thermal expansion during drying and preheating can be absorbed and thermal deformation can be suppressed.

Further, when the base member is arranged in the metal case and the irregular refractory is poured, the position of the base member is fixed by the position fixing member and the base member is restrained by the position fixing member. When pouring fixed refractories,
The plant is securely implanted at a predetermined position without being lifted.

[0015] Further, after the amorphous refractory is poured between the metal case and the base member and cured, it is sufficiently heated and dried at a temperature of 350 ° C or more. No explosion or destruction.

Further, when the ceramic plate is implanted in the implant groove of the base member, a spacer is arranged between the base member and the ceramic plate and the adhesive is poured in a restrained state, so that the ceramic plate is securely positioned at a predetermined position. It is planted.

Further, since the water-cooled stiffener is dried while being cooled, there is an effect that the thermal deformation of the water-cooled stiffener can be suppressed and the side dam, particularly, the metal case can be suppressed from being deformed. can get.

In this way, thermal deformation of the side weir during drying and preheating of the side weir is minimized, its shape is ensured stably, and the sealing property of the molten metal in the movable mold is stably ensured. It can stabilize the continuous casting operation and produce high quality and homogeneous slabs.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in FIGS. 1 (a) to 1 (c). The side weir 9 of the present invention includes a metal case (SS41) 10, an irregular refractory (fused SiO ₂ ) 11 housed in the metal case, and a base member (high) implanted in the irregular refractory. Alumina)
12, the base member to the cooling drum Ra, and Y-shaped ceramic plate (Si ₃ N ₄ -BN-AlN quality) 13 as planted to the end face and the sliding of the Rb, embedded in the base member It consists of a heater 14 (SiC heating element), and a rigid body (S
S41) 16 is attached.

In the side weir according to the present invention, an irregular-shaped endurance in which the side plate 10a of the metal case 10 and the base member 12 are implanted.
Between the refractory 11 and the refractory, a shrinkable heat insulating material 22 having a shrinkage ratio of 30 to 50% for absorbing thermal expansion of the refractory is loaded.

A stiffener 16 is fastened to the bottom plate 10b of the metal case by a plurality of fastening bolts / nuts 18 and 18a via a plurality of connecting bosses 17. This stiffener 16
Has a built-in cooling medium flow passage 19 so that it can be cooled.
1 and used.

Next, an outline of a method of manufacturing the side weir 9 of the present invention will be described. (1) First, a bottom plate 10a serving as an outer shell of a side dam and a side plate 1
The stiffener 16 is attached to the metal case 10 made of Ob via a plurality of connection bosses 17.

(2) The side plate 10 is placed in the metal case 10 .
The base member 12 is disposed so as to have a space for filling the irregular-shaped refractory 11 with the base member 12a. An insertion hole 12b for the heater 14 is formed in the metal case 10 and the base member 12, through which a rod (not shown) having substantially the same diameter as the heater 14 is inserted. The positions of the metal case 10 and the base member 12 are fixed. In this case, it is filled with the side plate 10a of the metal case 10.
A void is formed between the irregular refractory 11 and the expansion allowance of 1 to 2 mm. The void has a shrinkage of 30 to 50%. 2 to 4 mm thick heat insulating material (for example, product name "Khao wool") 2
2 is loaded.

(3) The metal case 10 and the base member 12 are restrained using a restraining member and a fastener (not shown). This is to prevent the base member 12 from floating when the irregular-shaped refractory 11 is poured around. In this way, the metal case 10 and the base member 12 are restrained, and the refractory 11 is poured around the metal case 10 and the base member 12.
After curing for 8 hours, release the restraint.

(4) Drying at a temperature of about 350 ° C. to 500 ° C. for 12 to 24 hours in a drying furnace to remove moisture from the refractory portion. This is to prevent explosion or destruction of the refractory portion due to rapid evaporation of residual water during preheating or casting of the side weir. At the time of this drying, the cooling medium is supplied to and circulated through the cooling medium flow passage in the stiffening body 16 to cool the stiffening body. This is to prevent the stiffener from being thermally deformed during drying, and it is sufficient that the outer surface of the stiffener is about 20 to 50 ° C.

(5) Y-shaped groove 12 for planting base member 12
a, a ceramic plate 13 having a similar shape is attached to a ceramics bond (for example, trade name "Sumiceram") 2
5 and then dried at a temperature of about 110 to 150 ° C. and polished with a grinder. The ceramic plate has a similar shape to the Y-groove 12a for planting,
a, which is formed by sticking with an adhesive.

When the ceramic plate 13 is to be implanted in the base member 12, a 1 to 5 mm diameter tex 24 as a position fixing spacer is provided on the bottom surface of the implantation Y-shaped groove 12a.
Are arranged in a plurality of rows, filled with an adhesive (ceramic bond, for example, trade name "Sumiceram") 25, and a plurality of divided pieces 13a of the ceramic plate 13 are pressed and stuck thereon, and the Y-shaped ceramic plate 13 is attached. After the formation, a reinforcing adhesive (ceramic bond, for example, trade name "KSB-1") 26 is applied to the vicinity of the side surface boundary between the base member 12 and the ceramic plate 13 to reinforce it.
Dry at a temperature of about 10 to 150 ° C.

(6) The surface of the ceramic plate 13 is polished by a polishing device to finish the surface roughness to 10S or less. This is to reduce the sliding resistance with the cooling drum at the start of continuous casting, prevent a start-up trouble in the drive device of the cooling drum, and protect the smoothness of the drum end surface essential for the melt seal.

(7) The rod is pulled out from the heater insertion hole of the base member 12, and the heater 1 is inserted into the heater insertion hole 12b.
4 and is fixed to the metal case 10.

The thus obtained side weir 9 of the present invention is hardly deformed when the amorphous refractory 11 is dried, has a very good shape, is strong, and is connected to a stiffener. -The fixed state can be maintained well.

A pair of side dams to which the stiffeners 16 are connected and fixed as described above are respectively attached to the support 21, and the side dams are brought into contact with both end faces of the cooling drums Ra and Rb, and are preheated by the heater 14. When the value corresponding to the surface temperature of the ceramic plate reached 1470 ° C., the deformation of the side weir was observed, and almost no deformation was observed in the side weir. Therefore, casting was started and a wide thin cast piece having a width of 1200 mm and a thickness of 5 mm was continuously cast.

Conventionally, it has been confirmed that the side weir has been deformed clearly after preheating, and that the deformation has occurred in the left and right and up and down imbalances.
In some cases, the side weir lost its function in a short period of time, making it impossible to continue casting.However, in the embodiment of the present invention, it was possible to preheat to the set temperature in a short time, and it was also possible to prevent troubles related to the side weir during casting operation. In addition, it was possible to stably cast a slab having a good shape and fulfilling the function as a side weir for a long time.

In the present invention, when preheating the side weir, the thermal deformation of the side weir can be sufficiently suppressed. For example, if the measurement accuracy of the preheating temperature can be improved, the power supply to the heater and the input of the power during the preheating can be performed. The time can be patterned, and each time casting is started, the input power and the input pattern can be made substantially constant, and the side dam can be preheated more stably.

In addition, reproducible minute thermal deformation can be imparted to the side weir, and the sealing of the molten metal by the side weir can be stabilized. In addition, the maximum preheating temperature of the ceramic plate can be increased to 1550 ° C., which is near the limit,
It has become possible to enhance the preheating effect of the side dam.
Conventionally, thermal deformation of the side dam due to preheating was large and unstable, so that it was only possible to raise the temperature up to 1350 ° C. in view of safety, and the preheating effect was not sufficient.

As described above, in the present invention, when preheating the side weir, the thermal deformation of the side weir can be suppressed to a minimum, and it is possible to preheat to a considerably high temperature region in a short time and to preheat to a predetermined temperature. The variation in the time required for the casting has been greatly reduced, and continuous casting can be started as planned.

The present invention is not limited to the above-described embodiment. The side weir structure, materials, adhesives, and manufacturing conditions include cooling drum conditions (end face material, dimensions, shape, etc.) and side weir conditions. (Structure, dimensions, shape, combination of materials, preheating conditions, etc.), operating conditions of continuous casting (temperature, speed, dimensions, etc.) and the like can be appropriately changed within the scope of the claims of the present invention. .

[0037]

According to the side weir of the present invention, since the shrinkable heat insulating material is loaded between the side plate of the metal case and the refractory having the base member planted therein , the side dam is not required for drying and preheating. Absorbs thermal expansion of amorphous refractories and suppresses thermal deformation.

Further, when the base member is arranged in the metal case and the irregular refractory is poured, the position of the base member is fixed by the position fixing member and the base member is restrained by the position fixing member. When pouring fixed refractories,
The plant is securely implanted at a predetermined position without being lifted.
In addition, after the refractory is poured between the metal case and the base member and cured, it is sufficiently heated and dried at a temperature of 350 ° C or more, so that there is no residual water, and the refractory part explodes or breaks during preheating of the side dam or casting. I will not do it.

Further, when the ceramic plate is implanted in the implant groove of the base member, a spacer is arranged between the base member and the ceramic plate, and the adhesive is poured in a restrained state. It is planted. In addition, since the water-cooled stiffener is dried while being cooled, effects such as suppression of thermal deformation of the water-cooled stiffener during drying and suppression of deformation of the side dam, particularly the metal case, can be obtained.

In this way, thermal deformation of the side weir during drying and preheating of the side weir is minimized, its shape is stably ensured, and the sealing property of the molten metal in the movable mold is stably ensured. It can stabilize the continuous casting operation and produce high quality and homogeneous slabs.

More specifically, (1) the thermal deformation of the side weir during drying and preheating is reduced by half
The following can be suppressed. (2) The variation of the thermal deformation of the side dam every time the casting is started can be suppressed to 1/3 or less of the conventional one. (3) The shape of the side weir is good even at the time of casting, and the frequency of molten metal leakage can be reduced to 1% from 30% of the conventional case. (4) The preheating temperature can be increased, the amount of sliver produced on the side weir surface during casting can be greatly reduced, and the frequency of slab infiltration into the slab is reduced to 1/10 of the conventional rate. Can be. (5) The reproducibility of the preheating is improved, the casting can be started as planned, and the casting operation efficiency can be improved by about 30% as compared with the conventional case.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing an embodiment of the present invention, wherein FIG. 1 (a) is a front explanatory view of a side weir viewed from a pool part side, FIG. 1 (b) is a side sectional explanatory view of FIG. (C) The figure is Ba in the figure (a).
-Bb arrow sectional expansion explanatory drawing.

FIG. 2 is an elevation explanatory view showing an example of a continuous casting apparatus for a twin-drum wide thin cast slab that implements the present invention.

FIG. 3A is an explanatory plan view showing a state of a side weir arrangement in a twin-drum type continuous casting apparatus for a wide and thin cast slab that implements the present invention. (B) Drawing is a front explanatory view of (a) figure.

4A and 4B show an example of a side weir in a conventional twin-drum continuous casting apparatus, in which FIG. 4A is an explanatory front view as viewed from the pool portion side, and FIG. 4B is an arrow Aa-Ab in FIG. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Side weir 2 Frame plate 3 Bottom plate 4 Side weir case 5 Refractory 6 Base material 7 Ceramic layer 7a Central region (ceramic layer) 7b Peripheral region (ceramic layer) 8 Heater 9 Side weir 10 Metal case 10a Metal case side plate 10b Metal case Bottom plate 11 Irregular refractories 12 Base member 12a Y-shaped groove for planting 12b Heater insertion hole 13 Ceramic plate 13a Split piece (ceramic plate) 14 Heater 16 Stiffener 17 Connection boss 18, 18a Fastening bolt / nut 19 Cooling medium flow passage DESCRIPTION OF SYMBOLS 20 Support bolt / nut 21 Support 22 Shrinkable heat insulating material 23 Position fixing material 24 Spacer 25 Adhesive 26 Reinforcement adhesive a Inner nozzle b Outer nozzle c Cast piece e Melt M Meniscus p Pool hole Ra, Rb Cooling drum Sa , Sb side weir

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuo Shishita 1-1-1, Higashihama-cho, Yawatanishi-ku, Kitakyushu-city, Fukuoka Prefecture Inside Kurosaki Ceramics Co., Ltd. (72) Inventor Yasushi Tsutsui 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation (72) Inventor Yasuhiro Yamagami 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Headquarters (72) Inventor Mamoru Yamada 3434 Shimada, Hikari-shi, Yamaguchi Prefecture New Japan (72) Inventor Hideki Oka 3434 Shimada, Hikari-shi, Yamaguchi Prefecture Nippon Steel Corporation Hikari Works (56) Reference JP-A-62-176647 (JP, A) JP-A-7-68358 (JP, A) JP-A-7-68353 (JP, A) JP-A-7-60411 (JP, A) JP-A-7-60410 (JP, A) JP, U) Hira 3 101339 (JP, U) (58 ) investigated the field (Int.Cl. ^7, DB name) B22D 11/06 330

Claims (3)

(57) [Claims] 1. A metal case in which a water-cooled stiffener is fixed to the back surface, a base member having a built-in heater and having a Y-shaped groove for implanting a ceramic plate disposed in the metal case; In a twin-drum continuous casting side dam composed of a filled refractory material and a ceramic plate planted on a base member so as to slide on the end face of a cooling drum, a side plate of a metal case is not supported.
A double-drum type continuous casting side weir characterized by being provided with a shrinkable heat insulating material between a fixed refractory material. 2. When a base member having a heater insertion hole and a Y-shaped groove for implanting a ceramic plate is provided in a metal case having a water-cooled stiffener fixed to the rear surface, the metal case is fixed to the metal case by using a position fixing member. An expansion allowance is formed between the base members, and the shrinkable heat insulating material is loaded, a rod is inserted into the heater insertion hole, the metal case and the base member are restrained, an irregular refractory is poured, and after curing, water cooling is performed. Heating at a temperature of 350 ° C or higher while cooling by supplying a cooling medium to the stiffener
After drying, heating and drying, a ceramic plate is planted in the planting Y-shaped groove of the base member, and a heater is inserted and fixed in a heater insertion hole formed by a rod-shaped body, which is a twin-drum type. Manufacturing method of side weir for continuous casting. 3. The ceramic plate according to claim 2, wherein a ceramic plate is implanted in the implanted Y-shaped groove of the base member after heating and drying, wherein a spacer is provided between the implanted Y-shaped groove and the ceramic plate. Arranging the base member and the ceramic plate in a constrained state, pouring an adhesive, solidifying and bonding, and polishing the surface of the ceramic plate to a roughness of 10 S or less. .