JPS61212463A - Electromagnetic stirrer - Google Patents

Abstract

PURPOSE:To maintain the uniform temp. of a molten steel and to improve the quality of the molten steel from a columnar crystal to equiaxed crystal by contg. a cylindrical core formed with plural slots and plural coils into a cylindrical case having the inside peripheral surface conforming to the outside peripheral surface of casting mold thereby forming an electromagnetic stirrer. CONSTITUTION:The plural slots 10a are formed along the inside peripheral surface of the cylindrical core 10 and the coils 12 which generate rotating magnetic fields are provided into the respective slots 10a on the inside peripheral side of the core 10. Such cylindrical core 10 is contained into the cylindrical case 14 having the inside peripheral surface shaped to meet the outside peripheral surface of the casting mold 5 to form the electromagnetic stirrer 17. The molten steel 2 is poured into the mold 5 and thereafter the stirrer 17 is disposed to the outside periphery of the mold 5. AC current is then supplied to each coil 12 to generate the rotating magnetic fields. The molten steel 2 in the mold 5 is stirred by the rotating magnetic fields, by which the temp. of the molten steel 2 is made uniform and the columnar crystal is improved in quality to the equiaxed crystal.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to an electromagnetic stirring device for stirring molten metal (molten steel) poured into a mold during the ingot manufacturing process.

"Prior Art" As is well known, the manufacturing process of ingots, which are raw materials, such as rolling and forging, is as shown in FIGS. 3(a), (b), and (c). First, as shown in FIG. 3(a), the molten steel 2 produced by the converter I is transferred to the dollar 3, and then placed on the trolley 4 as shown in FIG. 3(b). The liquid is injected into a cylindrical mold 5 placed therein. Then, as shown in FIG. 3(c), the molten steel 2 solidifies in the mold 5 to form an ingot 6.

``Problems to be solved by the invention'' In recent years, continuous casting equipment has been equipped with electromagnetic stirring devices to improve the quality of columnar crystals produced during the solidification process of molten steel into equiaxed products. I'm raising it. However, in the above-mentioned manufacturing process of the ingot 6, no quality improvement treatment was performed until the molten steel 2 injected from the ladle 3 into the mold 5 solidified in the mold 5 to become the ingot 6. As a result, in the process of solidifying the molten steel 2, columnar crystals are generated, and the ingot 6 in which the columnar crystals are generated cracks during blooming, resulting in a poor yield.

The present invention was made in view of the above-mentioned circumstances, and in the process of manufacturing ingots, by stirring the molten steel poured into the mold, the temperature of the molten steel is made uniform and the columnar crystals are transformed into equiaxed crystals. The purpose is to provide an improved electromagnetic stirring device.

"Means for Solving the Problems" The present invention provides an electromagnetic stirring device for stirring molten metal poured into a cylindrical mold, which includes a cylindrical core having a plurality of slots formed along its inner circumferential surface. , a plurality of coils that are provided in the plurality of slots and generate a rotating magnetic field on the inner peripheral side of the core, and a cylinder that accommodates the core and the coil and has an inner peripheral surface shaped to correspond to the outer peripheral surface of the mold. It is characterized by having a case shaped like this.

"Operation" The rotating magnetic field generated by the coil stirs the molten steel injected into the mold, so the temperature of the molten steel becomes uniform and the quality of the columnar crystals is improved to uniform metal.

"Embodiments" Examples of the present invention will be described below with reference to the drawings.

FIGS. 1(A), 1(B), and 2 are diagrams showing the configuration of an embodiment of the present invention. In these figures, lO is a cylindrical core in which a plurality of slots lOa, 10a... are formed along the inner peripheral surface, and 12.12... are provided in each slot lOa, 10a... This is a coil that generates a rotating magnetic field on the inner peripheral side of the core IO.

These core 10 and coil 12 as a whole have approximately the same shape as the stator of the induction motor, and are a cylindrical case with an inner circumferential surface shaped to correspond to the outer circumferential surface of the mold 5! It is housed in 4. The case 14 consists of a water cooling jacket 1'4a that forms both upper and lower end surfaces and an inner peripheral surface, and a cover 14b that forms an outer peripheral surface.The cover 14b is provided with hanging ears 15, 15, . 14
A has a heat insulating material 1 interposed between it and the outer peripheral surface of the mold 5.
6.16 ... is provided. By the above,
An electromagnetic stirring device 17 is configured. And hanging ears 1
5. By attaching the lifting jig 18 to 15... and lifting this lifting jig I8 with a crane or the like,
It is possible to move the entire electromagnetic stirring device 17 having the above-described structure in vertical and horizontal directions.

In such a configuration, after the molten liquid 12 is poured into the mold 5 from the droplet 3, an electromagnetic stirring device 17 is placed on the outer periphery of the mold 5 as shown in FIG.
...supplies alternating current to generate a rotating magnetic field.

As a result, the molten steel 2 injected into the mold 5 is stirred by the rotating magnetic field, so that the temperature of the molten steel becomes uniform and the quality of columnar crystals is improved to equiaxed crystals.

"Effects of the Invention" As explained above, according to the present invention, in an electromagnetic stirring device that stirs molten metal poured into a cylindrical mold, a cylindrical mold with a plurality of slots formed along its inner circumferential surface is used. a core, a plurality of coils provided in the plurality of slots and generating a rotating magnetic field on the inner peripheral side of the core, and an inner peripheral surface that accommodates the core and the coils and has a shape corresponding to the outer peripheral surface of the mold. Since the molten steel injected into the mold is stirred by the rotating magnetic field generated by the coil, the temperature distribution of each part of the molten steel in the mold is made uniform, and the cylindrical case is The quality of the crystals is improved to equiaxed crystals, and as a result, cracks that occur during blooming of the ingot can be prevented and the yield can be improved.

[Brief explanation of the drawing]

Figures 1 (A) and (B) are a plan sectional view and a front sectional view showing the configuration of an embodiment of the present invention, and Figure 2 is a partially cutaway front view of the embodiment arranged around the outer periphery of a mold. , Figure 3 (a), (
B) and (C) are diagrams for explaining the ingot manufacturing process. 10...core, 12...coil,
14... Case, 14a...
Water cooling jacket, 14b...Cover.

Claims (1)

[Claims] An electromagnetic stirring device that stirs molten metal poured into a cylindrical mold includes a cylindrical core having a plurality of slots formed along its inner circumferential surface, and a cylindrical core provided in the plurality of slots and an inner periphery of the core. An electromagnetic stirrer comprising: a plurality of coils that generate a rotating magnetic field on one side; and a cylindrical case that houses the core and coils and has an inner circumferential surface shaped to correspond to the outer circumferential surface of the mold. Device.