JP3119974B2 - Twin drum type side dam for continuous casting and base member thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[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 prior art, as shown in FIG. 4, 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, the solidified shell is formed by cooling with a cooling drum, and the solidified shell is pressed and integrated at 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.

As shown in FIG. 5, the side dams Sa and Sb are indispensable for sealing the molten metal e (hatched portion) between the cooling drums Ra and Rb. Such side weirs are, 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 6 implanted in the refractory material, a heater 8 incorporated in the base member, and a ceramic plate 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 (ceramic plate) and the end face of the rotating cooling drum. For this reason, the ceramic plate is particularly in close contact with the end face of the cooling drum. It is necessary to have a surface which is sufficiently conformable to both end faces of the drum in terms of shape, and to have 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 shown in FIG. 6, in which a ceramic plate 7 is implanted on the surface layer.
Base member 6 having a U-shaped groove and a heater insertion hole therein
Is disposed on a side weir case 4 composed of a frame plate 2 and a bottom plate 3 via a heat-insulating refractory material 5, and an irregular refractory 5 a is poured into a peripheral portion thereof, and after curing and drying, the Y of the base member 6 is removed. A ceramic plate 7 having a similar shape to that of the ceramic plate 7 is provided in the groove, bonded by using an adhesive, and the surface of the ceramic plate is polished.

Conventionally, a fired refractory is used for the base member 6 forming the side weir 1, and in particular, from the viewpoint of reducing thermal deformation, the base member is not formed as an integral body.
It is generally obtained by combining several divided plates 6, 6a, 6b, 6c cut out from a fired refractory obtained by molding and firing (suppression of deformation by thermal stress absorption), and by machining and bonding. Was. For this reason, when manufacturing a base member composed of several divided plates, a considerably complicated process is required, and there is an increasing demand for improvement in terms of manufacturing cost, construction period, and the like.

The outline of the manufacturing process of this conventional base member is as follows. (1) A refractory material is kneaded with a binder, molded, dried, and fired. A fired refractory obtained is cut into a plate having a predetermined size. Is ground. (3) The divided plates are arranged to form a base member material, and a Y-shaped ceramic plate planting groove and a ruled line of the outer shape of the base member are drawn on the surface thereof. (4) A ceramic plate planting groove is formed in each of the divided plates by a grinder. (5) A heater insertion hole is formed in each divided plate by a drill. (6) The outer shape of each divided plate is adjusted by a grinder. (7) An adhesive is applied to the respective end surfaces of the divided plates, aligned, and bonded. In this case, it is dried in a fixed state using a fixing tool.

As described above, in order to obtain the base member,
A considerably complicated process is required, the construction period of the side weir is long, and the manufacturing cost of the side weir is high.

[0011]

SUMMARY OF THE INVENTION The present invention simplifies the manufacturing process of the base member constituting the side dam of the twin drum type continuous casting apparatus, shortens the manufacturing period of the side dam, and reduces the manufacturing cost of the side dam. It is intended to provide a side weir and a base member that can be achieved.

[0012]

The present invention is characterized in that a base member constituting a side dam of a twin-drum continuous casting apparatus is integrally molded by casting as a refractory material of an irregular shape. A base member in which a metal case, a heat insulating material, and an amorphous refractory are poured into a mold and integrally molded to form a heater insertion hole and a ceramic plate implant groove at the time of molding, and are disposed around the base member. A twin-drum type continuous refractory, comprising: a shaped refractory; a heater inserted into the heater insertion hole of the base member and fixed to the metal case; and a ceramic plate implanted in the ceramic implantation groove of the base member. Claim 2 is a casting side weir, wherein the base member provided in the metal case is made of a cast refractory similarly to an irregular refractory provided around the base member. After arranging the heating material, pour the amorphous refractory together with the mold, cure, remove the mold, use the other mold together with the rod, and arrange the rod-shaped body. After pouring and curing while forming the heater insertion hole and the ceramic plate installation groove, the mold is removed and dried, then the heater is inserted into the heater insertion hole formed in the base member and fixed to the metal case. A twin-drum type continuous casting side weir characterized by being constructed by implanting a ceramic plate in a groove.

According to a third aspect of the present invention, a base member provided on a metal case and an irregular refractory provided around the base member are provided.
A base member for a side dam of a block-shaped twin-drum continuous casting apparatus, which is made of a cast indefinite refractory of the same material, is formed integrally with a heater while forming a heater insertion hole and a ceramic plate implantation groove using a mold frame.

[0014]

In the present invention, the base member provided in the metal case can be cast as an irregular refractory into a mold and integrally molded.
The manufacturing period can be shortened, and the manufacturing cost of the side dam can be reduced. In addition, stable continuous casting can be performed for a long time without deterioration in the function as a side weir.

[0015]

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 implanted in the irregular refractory. (Al ₂ O ₃ -S
iC-C) 12 and a cooling drum R
a, Y-shaped ceramic plate (Si ₃ N ₄ -BN-AlN) 1 planted so as to slide on the end faces of a, Rb
3 and a heater (SiC heating element) 14 embedded in the base member.

The base member 12 used here is:
It is a refractory material of an irregular shape, which is cast into a mold and integrally molded. As shown in FIG. 2, a heater insertion hole 12a and a planting groove 12b for the ceramic plate 13 are formed.

FIG. 3 shows an example of a mold used when the base member 12 is cast and integrally molded. The mold includes an upper mold 15 and a lower mold 16.
A plurality of rods 17 for forming a large number of heater insertion holes 12a are provided, and a Y-shaped convex portion 15 for forming an implantation groove 12b of a Y-shaped ceramic plate 13 is provided on the upper die.
a is formed.

Therefore, the base member 12 is formed with a Y-shaped ceramic plate planting groove 12b by removing the mold after pouring the refractory for the base member into the mold through the pouring hole 18 and curing. The heater insertion hole 12a is formed by extracting the rod 17 after drying.

In the case of an amorphous refractory, the thermal conductivity is smaller than that of the fired brick, and the structure is coarse, so that the refractory is excellent in thermal stress absorption capacity, and has a property of not easily causing thermal deformation even in an integrated product. I have. The reason for integrally molding this base member with an irregular-shaped refractory in the present invention is also here.

The irregular-shaped refractory material for the base member used in the present invention is required to be excellent in crack resistance (low elasticity, low thermal expansion, high strength) and volume stability (low thermal expansion, high thermal conductivity). As a refractory material, Al ₂ O ₃ —SiC—C refractory material has high suitability, and as a binder, alumina cement has high suitability.

When a side weir is constructed using the base member obtained in this way, the steps after forming the base member are not so different from the conventional steps, but the outline thereof will be described. (1) A side plate 10a and a bottom plate 10b which are outer shells of the side weir 9
The base member 12 obtained by the present invention is disposed in a metal case 10 made of. The metal case 10 and the base member 1
2 is provided with a heater insertion hole, through which a pipe (not shown) having substantially the same diameter as this insertion hole is inserted, and a metal case 10 and a base are provided by disposing a position fixing member (not shown). The positional relationship of the member 12 is fixed. In this case, a space 19 serving as an expansion allowance is formed between the metal case 10 and the base member 12, and a fibrous refractory material having a shrinkage property (for example, trade name "Kaoh- ) Is loaded.

(2) The metal case 10 and the base member 12 are restrained by using a restraining member and a fastener (not shown). This is to prevent the base member 12 from being lifted or displaced when the irregular-shaped refractory 11 is poured around. In this way, the metal case and the base member are kept in a constrained state, the irregular-shaped refractory 11 is poured around the metal case, and after curing for 12 to 24 hours, the restraint is released.

(3) Drying in a drying furnace at a temperature of about 350 ° C. to 500 ° C. for 24 to 48 hours 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.

(4) Y-shaped planting groove 12 of base member 12
b, a ceramic plate having a similar shape to that of the ceramic plate is disposed, and a ceramic-based adhesive (for example, a trade name “Sumiceram”) is adhered and dried at a temperature of about 110 to 150 ° C. It has a shape similar to that of the groove 12b, is composed of a plurality of divided pieces, is adhered by a ceramic-based adhesive, and is formed in a Y-shape.

When the ceramic plate 13 is to be implanted in the base member 12, a plurality of rows of position fixing spacers (not shown) are arranged on the bottom surface of the implantation groove 12a, and an adhesive is filled. After a plurality of divided pieces of the ceramic plate 13 are pressed and adhered to form a Y-shaped ceramic plate, a ceramic reinforcing adhesive (for example,
A trade name “KSB-1]) is applied to reinforce, and dried at a temperature of about 110 ° C.

(5) 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, and to prevent a start-up trouble in the drive device of the cooling drum.

(6) Heater insertion hole 12 of base member 12
a, and the heater 1 is inserted into the heater insertion hole.
4 and is fixed to the metal case 10.

As described above, the side weirs (a pair) of the present invention obtained by using the base member integrally formed of the irregular refractory are respectively attached to the support (not shown), and the respective side weirs are cooled. Abutting on both end surfaces of the drums Ra and Rb, preheating is started by a heater, and casting is started.
A wide and thin cast slab having a thickness of 5 mm and a thickness of 5 mm was continuously cast at a casting speed of 30 m / min for about 350 tons.

Table 1 shows the component composition of the base member of the side weir used in the present invention, the results of preheating the side weir, and the characteristics evaluation after the start of casting.

[Table 1]

As shown in Table 1, the deformation of the side weir (base member) is very small at the time of preheating and after the start of casting, which is smaller than that of the conventional base member formed by dividing and bonding the base member. And there is no inferiority, and like this conventional example,
No cracking was observed, and it was in a state where continuous use was possible.

As described above, in this embodiment, the thermal deformation at the time of preheating is small, and it is possible to easily preheat to the set temperature.
Also, there was no trouble related to the side weir during the casting operation,
It has been confirmed that the function as a side weir can be achieved over a long period of time and a cast piece having a good shape can be stably cast.

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.), 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. .

For example, in this embodiment, a block-shaped base member 12 is formed by casting an irregular-shaped refractory for a base member into a mold formed by an upper die 15 and a lower die 16 and integrally molding the same.
Is used to form the side weir 9, but when constructing the side weir, the metal case 10 is used as a mold, and the mold (eg, the upper mold 15) is used in combination with the mold to directly form the irregular refractory. 1
1. Irregular refractories for the base member may be sequentially cast and molded.

In this case, the irregular-shaped refractory 11 to be disposed around the base member 12 is cast into a metal case 10 together with a mold, molded and cured (solidified) to some extent. Can be made to function as a part of a mold, and the other mold can be used in combination to directly cast and cast the irregular-shaped refractory for the base member.

Also, the same refractory material as the refractory material for the base member and the refractory material provided around the base member are made of the same refractory material, and are simultaneously poured in advance using a mold, integrally molded, and used in a block shape. Alternatively, the metal case and the mold may be used together and directly poured into the metal case to be integrally molded.

[0036]

According to the side weir of the present invention, the base member provided in the metal case is obtained by casting the base member as an irregular refractory into a mold (sometimes combined with a metal case) and integrally molding. The manufacturing period of the weir can be shortened, and the cost of manufacturing the side weir can be reduced. More specifically, the construction period of the side weir can be shortened by 3 to 5 days, and the cost of producing the side weir can be reduced to 1/3.
Can be reduced.

[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 portion side, and FIG. 1 (b) is a sectional view taken along arrow Aa-Ab of FIG. FIG.

FIG. 2 is an explanatory view showing an example of a base member integrally molded into a block shape according to the present invention, wherein FIG. 2 (a) is a front explanatory view as viewed from the pool side, and FIG. FIG.

3A and 3B are examples of a mold structure for manufacturing the block-shaped base member of the present invention shown in FIG. 2, wherein FIG. 3A is a partially sectional plan view, and FIG. (C) is a sectional view taken along the line Da-Db in FIG.

FIG. 4 is an elevational explanatory view showing an example of a continuous casting apparatus for a twin-drum wide thin cast slab that implements the present invention.

FIGS. 5A and 5B are explanatory views showing the arrangement of side dams in an example of a twin-drum type continuous casting apparatus for wide and thin cast slabs embodying the present invention, wherein FIG. 5A is a plan explanatory view and FIG. FIG.

6A and 6B show an example of a side weir in a conventional twin-drum continuous casting apparatus, in which FIG. 6A is an explanatory front view as viewed from the pool portion side, and FIG. 6B is an Ea-Eb arrow in FIG. FIG.

[Explanation of symbols]

 (Conventional) 1 side weir) 2 frame plate 3 bottom plate 4 side weir case 5 heat insulating refractory material 6 base material 6a, 6b, 6c, 6d (base member) divided plate 7 ceramic plate 8 heater (the present invention) 9 side weir 10 Metal case 10a (Metal case) Side plate 10b (Metal case) bottom plate 11 Irregular refractory 12 Base member 12a Y-shaped planting groove 12b Heater insertion hole 13 Ceramics plate 14 Heater 15 Upper die 15a Y-shaped convex part 16 Lower die 17 rod-shaped body 18 pouring hole 19 void 20 heat insulating sheet a inner nozzle b outer nozzle c slab e molten metal M meniscus p pool hole Ra, Rb Cooling drum Sa, Sb Side dam

Continued on the front page (72) Inventor Yasushi Tsutsui 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division (72) Inventor Akio Ishii 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel (72) Inventor Katsumi Kirihara 3434 Shimada, Oji, Hikari-shi, Yamaguchi Prefecture Inside Nippon Steel Corporation Hikari Works (56) References JP-A-3-207555 (JP, A) JP-A-62-176647 (JP, A) JP-A-7-68352 (JP, A) JP-A-7-68358 (JP, A) JP-A-7-60411 (JP, A) JP-A-7-60410 (JP, A) JP, A) JP-A-6-206774 (JP, A) JP-A-3-101339 (JP, U) JP-A-63-90548 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , (DB name) B22D 11/06 330

Claims (3)

(57) [Claims] 1. A base member in which a metal case, a heat insulating material, and an amorphous refractory are poured into a mold and integrally molded to form a heater insertion hole and a ceramic plate implant groove at the time of molding. It is characterized by comprising an irregular-shaped refractory disposed around, a heater inserted into the heater insertion hole of the base member and fixed to the metal case, and a ceramic plate implanted in the ceramic implantation groove of the base member. Side drum for twin drum type continuous casting. 2. A base member provided in a metal case is made of a cast refractory similarly to an amorphous refractory provided around the metal case, and after the heat insulating material is provided in the metal case, the irregular refractory is removed. After pouring and curing using a mold, remove the mold, place a rod using another mold together, and then form an irregular refractory for the base member into a heater insertion hole and a ceramic plate installation groove. After pouring and curing, the mold was removed and dried, then the heater was inserted into the heater insertion hole formed in the base member and fixed to the metal case, and the ceramic plate was implanted in the ceramic plate implant groove. A twin-drum continuous weir for continuous casting. 3. A base member disposed in a metal case and an irregular refractory disposed around the base member are made of a cast irregular refractory of the same material. A base member of a block-shaped twin-drum type continuous casting weir formed by casting while forming grooves.