JP4546748B2 - Continuous casting mold - Google Patents

Description

  The present invention relates to a continuous casting mold capable of changing the core installation level and thickness of an electromagnetic stirring device that electromagnetically stirs molten steel in a mold in a continuous casting facility for steel.

  Conventionally, non-metallic inclusions or gas contained in molten steel injected into a continuous casting mold is actively levitated and removed to obtain a slab with excellent surface quality. Continuous casting molds equipped with a stirring device are known. Since the magnetic stirrer is very expensive, in order to provide the magnetic stirrer at a low cost, it is common to install the core with the minimum height of the core and the upper end of the core aligned with the hot water surface. (See Patent Document 1).

  However, as the use of electromagnetic stirrers proceeds, there has been a demand to change the installation level of the electromagnetic stirrer depending on the cast steel type, casting speed, and the like. In addition, in order to increase the productivity of continuous casting equipment, a request has been made to increase the casting speed of 1 to 2 mm. However, when high-speed casting of about 3 m / min is performed, there is no flow due to an electromagnetic stirring device. However, since the molten metal surface is disturbed, it is necessary to lower the installation level of the electromagnetic stirrer during high-speed casting. Since they are fixed so as to coincide with each other, it is impossible to dispose only the electromagnetic stirring device at the lower position.

Then, the casting_mold | template for electromagnetic stirring apparatuses which can change the installation position of an electromagnetic stirring apparatus is proposed (refer patent document 2).
FIG. 6 is an explanatory view of a mold for an electromagnetic stirring device that can change the installation level of the conventional electromagnetic stirring device.

In FIG. 6, a molten steel cooling copper plate 2 is provided on the molten steel side outer surface of the mold cooling box 1, a molten water cooling copper plate 2 is provided with a cooling water channel 3, and a water supply chamber 4 for supplying and discharging water to the cooling water channel 3 and A drain chamber 5 is connected. The electromagnetic stirrer 3 provided with the core 4 for electromagnetically stirring the molten steel 8 is fixed to the mounting plate 12 provided on the anti-melting steel side and stored in the electromagnetic stirrer storage chamber 7. In this electromagnetic stirrer mold, the electromagnetic stirrer is installed between the mounting plate 12 of the electromagnetic stirrer and the mold cooling box 1 so that the installation level of the electromagnetic stirrer 3 can be changed in accordance with the cast steel type, casting speed and the like. Positioning spacers 13 are provided for setting the installation level in the vertical direction. When changing the level of the electromagnetic stirring device 3, the mounting plate 12 to which the electromagnetic stirring device 3 is attached is fixed to the positioning spacer 13 corresponding to the set installation level, and then fixed to the mold cooling box 1.
Japanese Utility Model Publication No. 58-49172 JP 2002-321040 A

  In order to change the level of the electromagnetic stirrer in the vertical direction, the mold with the electromagnetic stirrer needs to have different positioning spacers as many as the number of installation positions in the vertical direction. In addition, there is a problem that it takes time to mount and replace the electromagnetic stirrer on the positioning spacer.

  Accordingly, the present invention provides a continuous casting mold provided with an electromagnetic stirring device that can change the installation level and thickness of the core without requiring a separate member or electromagnetic stirring device for changing the installation level of the core. .

The present invention is a continuous casting mold for steel, in which a molten steel cooling copper plate is provided on the molten steel side outer surface, and the molten steel in the mold is electromagnetically stirred in a mold cooling box in which a cooling water channel is formed on the back side of the molten steel cooling copper plate. In a continuous casting mold provided with an electromagnetic stirrer storage chamber for storing an electromagnetic stirrer having a core for the core, the core comprises a split core divided into a plurality in the casting direction, the split core, The cores divided to change the installation level and thickness of the cores bound by integrally binding the split cores selected from the split cores, thereby changing the position of stirring in the mold It is characterized by being.

  In the present invention, it is possible to select the split core and change the installation level and thickness of the core. Therefore, it is not necessary to provide a reserve for the electromagnetic stirrer for each steel type slab, so that the equipment cost can be greatly reduced. Can do. Further, it is not necessary to replace the mold itself depending on the production type and steel type, and the time required for replacement can be shortened.

  FIG. 1 is a side sectional view of a continuous casting mold according to the present invention. In FIG. 1, a molten steel cooling copper plate 2 is provided on the molten steel side outer surface of the mold cooling box 1, a cooling water channel 3 is formed on the back side of the molten steel cooling copper plate 2, and a water supply chamber for supplying and discharging cooling water to the cooling water channel 3. 4 and a drain chamber 5 are provided. The mold cooling box 1 is provided with an electromagnetic stirring device storage chamber 7 for storing the electromagnetic stirring device 6. 8 is molten steel in a mold, 9 is a meniscus.

  FIG. 4 is a partial sectional view of the electromagnetic stirring device of the present invention, and FIG. 5 is a plan view of the electromagnetic stirring device of the present invention. 4 and 5, the electromagnetic stirrer is composed of a divided core 10 divided into a plurality of parts, and in FIG. 4, the first divided core 10a, the second divided core 10b, and the third divided core 10c divided into three parts are provided. The thickness of the upper first divided core 10a is set to 50 mm, the thickness of the intermediate second divided core 10b is set to 150 mm, and the thickness of the lower third divided core 10c is set to 50 mm. The divided cores 10a, 10b1, and 10c are combined according to the installation position of the core, and are bundled and integrated by a plurality of core binding members 11a, 11b, and 11c.

  Next, a method for changing the installation level and thickness of the core of the continuous casting mold provided with the divided core according to the present invention will be described with reference to FIGS.

  Generally, in continuous casting equipment, many types of steel are cast, and it is necessary to reduce the thrust that changes the position of agitation in the mold depending on the type of steel. As is clear from the following examples, the core depends on the casting speed and type of steel. In the present invention, it is possible to continuously cast various types and steel types by selecting the split core and changing the level and thickness.

  In FIG. 1, since there is no melt level fluctuation of the molten steel 8 in the mold at a casting speed of 1.5 m / min or less, the first divided core 10a divided into three parts is used in order to maximize the thrust of the electromagnetic stirring device 6. As shown in FIG. 4, the second divided core 10b and the third divided core 10c are united by core binding members 11a, 11b, and 11c to form a core, and the meniscus 9 in the mold and the upper first The molten steel 8 is electromagnetically stirred by being housed in the electromagnetic stirring device housing chamber 2 so that the upper surfaces of the one-divided cores 10a coincide.

  By adopting the core arrangement shown in the present embodiment, for example, the molten steel in the mold is actively agitated like medium carbon steel, the molten steel temperature is made uniform, the impurities in the molten steel are raised, Vertical cracking can be prevented.

  When the casting speed is 1.5 m / min to 2 m / min, as shown in FIG. 2, the meniscus 9 in the mold is installed so that the upper surfaces of the first divided cores 4 a coincide with each other. The split core 4b is used in an integrated manner.

  By selecting the first divided core 10a and the second divided 10b according to the present embodiment, the meniscus 9 can be actively stirred, so that the properties of the slab surface can be improved.

  When the casting speed is as fast as 2 m / min to 3 m / min, as shown in FIG. 3, the second divided core 10b and the third divided core 10c are used and used in a state lowered by 50 mm from the meniscus in the mold. To do. It is suitable for steel types that actively stir using the flow of molten steel discharged from a nozzle immersed in the mold.

It is side part sectional drawing of the casting_mold | template for continuous casting of 1st Example by this invention. FIG. 4 is a side sectional view of a mold showing a second embodiment of the present invention. FIG. 6 is a side sectional view of a mold showing a third embodiment of the present invention. It is a fragmentary sectional view of the electromagnetic stirring apparatus of this invention. It is a top view of the electromagnetic stirring apparatus of this invention. It is side part sectional drawing of the casting mold for continuous casting which uses the conventional electromagnetic stirring apparatus.

Explanation of symbols

1: Mold cooling box 2: Molten steel cooling copper plate 3: Cooling channel 4: Water supply chamber 5: Drainage chamber 6: Electromagnetic stirrer 7: Electromagnetic stirrer storage chamber 8: Molten steel in the mold 9: Meniscus 10: Split core 10a: First Divided core 10b: second divided core 10c: third divided cores 11a, 11b, 11c: core binding member 12: mounting plate 13: positioning spacer

Claims (1)

A mold for continuous casting of steel, which is provided with a molten steel cooling copper plate on the outer surface of the molten steel, and a core for electromagnetically stirring the molten steel in the mold in a mold cooling box in which a cooling water channel is formed on the back side of the molten steel cooling copper plate. In a continuous casting mold in which an electromagnetic stirrer storage chamber for storing an electromagnetic stirrer is provided, the core is composed of a split core divided into a plurality of parts in the casting direction, and the split core is formed of the split core. It is a core that is divided to change the installation level and thickness of the bundled core by integrally bundling the divided core selected from among them, thereby changing the position of stirring in the mold. Features a continuous casting mold.

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