JP2788208B2 - Twin-drum continuous casting machine - 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 casting apparatus for producing a thin strip directly from a molten metal, and more particularly to the occurrence of molten metal due to convex portions formed on both end faces of a cooling drum and wear of side dams. The present invention relates to a device that prevents the above.

[0002]

2. Description of the Related Art FIG. 1 is a perspective view showing an outline of a main part of a conventional twin-drum continuous casting apparatus. In FIG. 1, a pair of cooling drums 1, 1 and both end surfaces 1a,
A pool portion 4 is formed by a pair of side weirs 2 and 2 pressed against 1a by pressing devices 3 and 3. The molten metal R continuously supplied to the pool 4 is supplied to the cooling drum 1
The cooling drum 1 solidifies by cooling and is sent downward from between the pair of cooling drums 1 rotating in the direction of the arrow to form a thin strip-shaped slab S.

[0003] In such a twin-drum continuous casting apparatus, ingots are easily generated on the surface of the molten metal in the pool 4,
In particular, it is likely to occur at the end of the cooling drum or around the side weir remote from the pouring nozzle (not shown) located substantially at the center of the pool. When the generated metal is bitten by the peripheral edge of the cooling drum with the rotation of the cooling drum, a concave pressing deformation occurs at that portion. As a result, a convex deformation occurs on the drum end surface near the indentation deformation portion.

As shown in FIG. 2A, when a convex deformation (convex portion) m occurs on the cooling drum end surface 1a, the convex portion m is shown in FIG. As described above, when moving to the lower position of the side weir 2, the gap g between the cooling drum end face 1a and the side weir 2 is opened downward. As a result, the sealing performance is reduced, and molten steel leaks out from the gap g, thereby deteriorating the end shape of the slab. If the molten steel leak becomes severe, casting may not be continued.

In the twin drum type continuous casting apparatus, the side dams 2 are often swung along the cooling drum end faces 1a, 1a in order to prevent the ingot from sticking to the side dams 2, 2. In this case, in the above-described example, the wear of the side weir 2 progresses due to the convex portion m of the cooling drum end surface 1a, so that the molten steel leaks violently and the life of the side weir 2 is shortened.

[0006] As a device for peeling off the metal sticking to the end face of the cooling drum, a device for pressing a scraper disk made of carbon against the end face of the drum while rotating it is known, for example, from JP-A-5-161946.
However, this device can peel off the adhered metal, but cannot correct the protrusion.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a twin-drum continuous casting apparatus in which convex portions formed on both end surfaces of a cooling drum are corrected so as not to cause leakage of molten metal.

[0008]

According to the present invention, there is provided a twin-drum continuous casting apparatus comprising a pair of rotating cooling drums and a pair of side weirs slidingly contacting both end surfaces of the cooling drum. An apparatus for continuously casting thin ribbon-shaped slabs by supplying a molten metal to a basin section, wherein a drum end surface grinding device holding a grinding tool at a distance of 10 to 100 μm from the cooling drum end surface sliding with the side weir is provided. It is characterized by having been provided. In addition, the drum end surface grinding device is characterized by comprising a position control cylinder attached to a gantry via a load detector, and a grinding tool connected to a rod of the position control cylinder.

[0009]

The present inventor has found that when the height of the protrusions formed on both end faces of the cooling drum exceeds 100 μm, molten steel leaks from the gap between the end face of the drum and the side weir. If a drum end surface grinding device holding a grinding tool is provided at a distance of 10 to 100 μm from the end surface of the cooling drum that slides with the side weir, the convex portion is selectively removed by the grinding tool. At this time, if the position of the grinding tool is more than 100 μm from the end face of the cooling drum, the height of the convex portion cannot be suppressed to 100 μm or less. As a result, the molten metal leaks and the side dam is worn. On the other hand, the position of the grinding tool was
If the distance is less than m, the drum end face may be scraped off by a grinding tool and flawed due to the lateral runout caused by the rotation of the cooling drum.

Therefore, in order to efficiently prevent the molten metal from leaking and to suppress the wear of the side weir, it is necessary to provide the grinding tool at a distance of 10 to 100 μm from the end face of the cooling drum.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. The same members and parts as those of the conventional apparatus shown in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted. 3 is a side view showing a main part of the twin-drum continuous casting apparatus, FIG. 4 is a sectional view taken along line XX of FIG. 3, and FIG. 5 is an enlarged sectional view of the drum end surface grinding apparatus 5 of FIG.

The cooling drum end face 1a shown in FIG. 3 is plated with, for example, Ni, and the surface of the side weir 2 which comes into contact with the cooling drum end face 1a is fitted with a ceramic such as BN. A drum end surface grinding device 5 is disposed to face the sliding surface of the cooling drum end surface 1a with the side weir 2.

As shown in an enlarged sectional view in FIG. 5, the drum end surface grinding apparatus 5 has a hydraulic type position control cylinder 9 supported by a fixed holder 7 attached to a gantry 6 with a load detector 8 interposed therebetween. , Position control cylinder rod 9a
Is connected to the moving holder 10 via a grinding wheel rotating device 12 using an air motor. A grinding tool 11 using a grindstone is connected to and supported by the grindstone rotating device 12 via three gears 13. The grinding tool 11 is a grinding wheel rotating device 12
, And the gap with the drum end surface 1a can be adjusted in units of 1 μm by the position control cylinder 9. As the grinding tool 11, a file or a cutting tool can be used in addition to a grindstone. When a grindstone is used, for example, an Al ₂ O ₃ material can be used, and the particle size is about # 80. Is good.

Next, the operation of the present apparatus will be described. FIG.
The grinding tool 11 is gradually approached and brought into contact with the cooling drum end face 1a by the position control cylinder 9 shown in FIG.
At this time, the load detector 8 is the cooling drum end face 1 of the grinding tool 11.
The reaction force due to the contact with a is detected, and when the reaction force rises, the position control cylinder 9 is stopped. The stop position is set as a reference position of the grinding tool 11, and the grinding tool 11 is retracted from the reference position by 10 to 100 μm by the position control cylinder 9, so that the grinding tool 11 and the cooling drum end surface 1 a
Is adjusted to 10 to 100 μm.

The convex portion formed on the end face 1a of the cooling drum is shaved by a grinding tool 11 rotating in the same direction as the cooling drum so that the height thereof becomes 10 to 100 μm.
The grinding tool 11 is worn by shaving off the projections, but the amount of wear is relatively small, so that the grinding tool 1 is cast in about 60 minutes.
There is no need to adjust the position of (1). When casting for a long time, the position control cylinder 9 may be used if necessary.
The gap between the grinding tool 11 and the end surface 1a of the cooling drum is adjusted. In this embodiment, the grinding tool 11 is rotated, but may be fixed.

[0016]

In the twin-drum continuous casting apparatus according to the present invention, the drum end surface grinding device is disposed with a predetermined gap from both end surfaces of each cooling drum. Since the convex portion can be effectively removed during casting, it is possible to prevent the molten metal from leaking due to the convex portion and the defective shape of the end portion of the slab, and further suppress the wear of the side dam.

Further, the drum end surface grinding apparatus according to the present invention comprises:
The holder supports and supports the grindstone, grindstone rotating device, position control cylinder, and load detector.The load detector detects the reaction force due to the contact of the grinding wheel with the drum end surface, and the grindstone position at the time when the reaction force rises is set as the reference position. Since the grinding wheel is retracted by a predetermined distance from the reference position by the position control cylinder, it is easy to adjust the gap between the grinding wheel and the end face of the cooling drum.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a conventional twin-drum continuous casting apparatus.

FIG. 2 is an explanatory view showing a convex portion formed on an end face of a cooling drum.

FIG. 3 is a front view showing a main part of a twin-drum continuous casting apparatus according to one embodiment of the present invention.

4 is a sectional view taken along line XX of FIG. 3;

FIG. 5 is an enlarged one-side sectional view showing the grinding device of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cooling drum 2 ... Side weir 3 ... Pressing device 4 ... Pool part 5 ... Drum end surface grinding device 6 ... Stand 7 ... Fixed holder 8 ... Load detector 9 ... Position control cylinder 10 ... Moving holder 11 ... Grinding tool (grinding stone) 12) Grinding wheel rotating device (air motor) 13 ... Gear S ... Thin strip slab R ... Molten metal

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-6-292948 (JP, A) JP-A-6-591 (JP, A) JP-A-63-207453 (JP, A) 95150 (JP, U) Japanese Utility Model 60-136849 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) B22D 11/06 330 B22D 11/04 311

Claims (2)

(57) [Claims] 1. A molten metal is supplied to a pool formed by a pair of rotating cooling drums and a pair of side weirs that are in sliding contact with both end surfaces of the cooling drum to continuously cast strip-shaped slabs. A twin-drum continuous casting apparatus, further comprising a drum end surface grinding device which holds a grinding tool at a distance of 10 to 100 μm from an end surface of the cooling drum which slides on the side weir. 2. A position control cylinder mounted on a gantry via a load detector, wherein the drum end surface grinding device comprises:
2. The twin-drum continuous casting apparatus according to claim 1, wherein the apparatus is constituted by a grinding tool connected to a rod of the position control cylinder.