JPH0760409A - Twin drum type continuous casting apparatus for al or al alloy - Google Patents

Abstract

PURPOSE:To obtain a twin drum type continuous casting apparatus for Al or Al alloy, by which solidified floating crystal is not produced in a cast slab and the defect is hardly occurred. CONSTITUTION:In the twin drum type continuous casting apparatus for casting the cast slab 10 by pouring molten non-ferrous metal 12 containing the aluminum alloy into a space demarcated with one pair of water cooling rolls 11A, 11B arranged in parallel and rotated mutually in the reverse direction and a short side weirs in slidable contact with both end surfaces of the drums, a vibrating plate 17 which is vibrated by an electromagnet 19 whose tip part is dipped into the molten metal 12 in almost parallel to the roll surface and between a pouring nozzle 13 and the drum surface.

Description

Detailed Description of the Invention

The present invention relates to a twin drum continuous casting machine for Al or Al alloys.

[0002]

2. Description of the Related Art In a steel production line, continuous production of molten steel (hereinafter referred to as "molten metal") in order to improve productivity and uniformity of material when manufacturing steel billets and the like. Casting equipment is used.

FIG. 3 shows an example of a continuous casting technique in which solidified floating crystals are not generated and defects are less likely to occur in a product cast in a continuous casting apparatus according to the prior art (see JP-A-4-288948). As shown in the figure, the water cooling drum 01A, 0
A cover body 04 having immersion walls 03A and 03B which are immersed in the molten steel 02 at a predetermined gap on the surface of 1B is arranged so as to cover the entire molten steel surface 05.

The gap between the immersion wall portions 03A, 03B hanging from the cover body 04 and the water cooling drums 01A, 01B becomes narrower toward the upper upstream side of the water cooling drum.
Inclined surfaces 06A and 06B are formed on 3A and 03B to prevent a molten steel circulating flow from being generated in the space 07.

[0005]

However, in the prior art shown in FIG. 3 described above, the flow of molten steel into the space 07 is prevented, but between the water cooling drums 01A and 01B and the immersion walls 03A and 03B. Since the melt level is narrow, the melt level 05 is irregularly wound around the drum due to the contact between the melt level 05 and the water-cooling drums 01A and 01B, and the vibration of the melt level 05 becomes violent and irregular. There is a problem that surface cracks and the like occur as a result of the winding of the oxide film being intermittent and irregular.

That is, since it is difficult to completely prevent oxidation even in a vacuum or an inert gas atmosphere, a thin oxide film is formed on the molten metal surface 05 of Al or a non-ferrous alloy containing Al. This oxide film forms the water cooling drums 01A and 01B and the molten metal surface 05.
It is rolled up with the rotation of the drum at the contact portion with

In the case of the apparatus shown in FIG. 3 described above, since the gap between the immersion wall portions 03A and 03B and the water cooling drums 01A and 01B is extremely narrow, there is no violent vibration when the oxide film is entrained. It occurs regularly, and this is a slab 08
It causes irregular cracks on the surface.

[0008]

A twin-drum type continuous casting apparatus for Al or Al alloy according to the present invention for solving the above-mentioned problems is a pair of drums arranged in parallel with each other and rotating in opposite directions,
In a twin-drum type continuous casting device for injecting a molten metal of aluminum or a non-ferrous alloy containing aluminum into a space defined by a short side weir slidingly contacting both end faces of this drum and casting a thin plate, a pouring nozzle and a drum surface And a vibration plate whose tip portion is immersed in the molten metal substantially parallel to the surface of the drum.

In the above structure, a heat-resistant cloth is provided between the vibrating plate and the drum, the heat-resistant cloth having the tip portion immersed in the molten metal and being in contact with the surface of the drum.

[0010]

A vibrating plate which is partially immersed in the molten metal is provided and the vibrating plate is vibrated to forcibly generate a short-wave periodic wave on the molten metal surface. The strength and weakness of the contact between the drum surface and the molten metal are periodically repeated by this periodic wave, so that the adhesion of the oxide film generated on the molten metal surface to the slab becomes extremely fine, causing cracks in the cast thin plate. Never.

Further, since the heat resistant cloth is partially immersed in the molten metal and installed so as to come into contact with the drum surface, the flow of the oxide film on the surface portion of the molten metal surface into the cast piece is blocked by the heat resistant cloth. Further, since the molten metal comes into contact with the drum periodically at the tip of the heat-resistant cloth by the vibrating plate, a large oxide film is not generated, and it becomes fine, and the heat transfer from the slab to the drum accompanying the rotation of the drum occurs. Was performed uniformly, the growth of the solidified shell at the drum contact portion was uniform, and the occurrence of cracks in the cast thin plate and the surface appearance defect were prevented.

[0012]

EXAMPLES Preferred examples of the twin-drum type continuous casting apparatus for Al or Al alloy according to the present invention will be described below.

(Embodiment 1) FIG. 1 is a schematic sectional view of a twin-drum type continuous casting apparatus according to this embodiment. As shown in the figure, a pair of water-cooled drums 11A and 11B that are arranged in parallel with each other and rotate in opposite directions to produce the slab 10, and a molten metal 12 in a space formed on the opposing surfaces of the water-cooled drums 11A and 11B.
Tundish 14 for injecting water through the pouring nozzle 13
A seal cover 15 for covering the upper surface of the poured molten metal 12, gas seal means 16 provided at both ends of the seal cover 15 for introducing a seal gas, and provided on the back side of the seal cover 15. Between the pouring nozzle 13 and the water cooling drums 11A and 11B and the water cooling drum 1
The tip of the molten metal 12 is formed substantially parallel to the surfaces of 1A and 11B.
And a diaphragm 17 which is dipped in.

Here, in this embodiment, the water cooling drum 11 is used.
A and 11B have a diameter of 600 mm and a width of 600 mm, and the seal gap (d) in the gas sealing means is 2
mm, and the introduced seal gas is a mixed gas of N ₂ and 3% H ₂ . The gas seal means 16 for introducing the seal gas is equipped with a seal gas nozzle 16a for blowing the seal gas, a seal gas header 16b, and a seal gas conduit 16c.

Further, a ferromagnetic material 18 is attached to the vibrating plate 17 which is provided with its tip portion immersed in the molten metal 12, and is provided so as to face the ferromagnetic material 18.
The magnetic force from the electromagnet 19 which gives a vibration of 20 Hz acts efficiently.

The vibration from the vibrating plate 17 is propagated to the molten metal 12 and causes contact and separation with the water cooling drums 11A and 11B. As a result, the film adhering to the slab 10 is extremely miniaturized and thinned, so that the oxide film (or the nitride film) generated in the melting region is very little adhered to the slab 10, resulting in The piece 10 was not cracked and the surface appearance was not defective.

In the figure, reference numeral 21 is a filter, 22 is a gutter, 2
3 is a heat insulating material, and 24 is a brush wheel.

The seal gas to be introduced is N ₂ gas and 3
% Mixed gas with H ₂ gas, for example, CO ₂ gas, A
A gas for preventing oxidation such as a mixed gas of r gas and 3% H ₂ gas or pure Ar gas may be appropriately used.

(Embodiment 2) FIG. 2 is a schematic view of a twin-drum type continuous casting apparatus according to this embodiment.

In the apparatus according to this embodiment, the tip of the molten metal 12 is provided between the vibrating plates 17A, 17B and the water cooling drums 11A, 11B provided in the apparatus shown in FIG.
Heat-resistant cloths 31A and 31B are provided which are immersed in and contact the surfaces of the drums 11A and 11B.

Further, in this embodiment, the vibrating plate 17 is used.
Vibrator 32A, 32 as means for vibrating A, 17B
B is attached to the surfaces of the vibrating plates 17A and 17B, and the vibrator 32 is cooled by cooling water.

When casting the slab 10, the space of the seal gas was filled with a mixed gas of N ₂ and 3% H ₂ gas, and then the casting was started. After casting, the surface of the molten metal 12 is the vibration plate 1
The vibration plate was vibrated at 200 Hz when 7A, 17B and the heat-resistant cloths 31A, 31B were raised to the immersion height.

In this embodiment, the amount of the seal gas introduced is 100.
It was carried out at L / min, but by this, the rapid growth of the oxide film was suppressed and the film slab 10 formed on the surface of the molten metal 12
Flow into the surface of the vibrating plates 17A, 17B and heat resistant cloth 3
Double shielded by 1A and 31B. In addition, the area where a new oxide film or the like is newly formed is the heat-resistant cloth 31A, 31B.
And the surface of the drums 11A and 11B are extremely narrow. Moreover, since the vibrating plates 17A and 17B force the contact separation between the molten metal and the drum surface in a short cycle, the width of the newly formed film is extremely small.

As a result, the adhesion of the film generated in the molten region to the cast slab 10 becomes extremely small and becomes extremely fine, and the cast slab 10 is not cracked.

[0025]

As described above with reference to the embodiments, according to the twin drum type continuous casting apparatus according to the present invention, the film such as the oxide film attached to the slab is extremely miniaturized and thinned by the vibration. The distribution of the slab solidified shell thickness in the contact area with the drum is uniform and there is no cracking of the cast slab to be cast,
Further, the appearance of the surface becomes good.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a twin-drum type continuous casting apparatus according to a first embodiment.

FIG. 2 is a schematic view of a twin-drum type continuous casting device according to a second embodiment.

FIG. 3 is a schematic view of a twin-drum type continuous casting device according to a conventional technique.

[Explanation of symbols]

 10 Castings 11A, 11B Water-cooled drum 12 Molten metal 13 Pouring nozzle 14 Tundish 15 Seal cover 16 Sealing means 17, 17A, 17B Vibration plate 18 Ferromagnetic material 19 Electromagnet 31A, 31B Heat resistant cloth 32 Transducer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takashi Yamane 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture Mitsubishi Heavy Industries Ltd. Hiroshima Research Laboratory (72) Inventor Hideaki Takatani 4-chome, Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture 6-22 No. 22 Hiroshima Research Laboratory, Mitsubishi Heavy Industries, Ltd.

Claims (2)

[Claims] 1. A molten metal of aluminum or a non-ferrous alloy containing aluminum is placed in a space defined by a pair of drums arranged in parallel with each other and rotating in opposite directions, and a short side weir slidingly in contact with both end faces of the drum. In a twin-drum type continuous casting device for pouring and casting a thin plate, a vibrating plate is provided between the pouring nozzle and the drum surface, and the tip portion of which is immersed in the molten metal substantially parallel to the drum surface. Twin drum type continuous casting equipment for Al or Al alloy. 2. The twin-drum type continuous casting apparatus for Al or Al alloy according to claim 1, wherein the tip portion is immersed in the molten metal between the vibrating plate and the drum and is in contact with the surface of the drum. A twin-drum type continuous casting apparatus for Al or Al alloy, which is provided with the following heat resistant cloth.