KR20170046342A

KR20170046342A - Apparatus of continuous casting

Info

Publication number: KR20170046342A
Application number: KR1020150146534A
Authority: KR
Inventors: 조원재; 김경수; 박종현
Original assignee: 현대제철 주식회사
Priority date: 2015-10-21
Filing date: 2015-10-21
Publication date: 2017-05-02
Also published as: KR101748954B1

Abstract

In a continuous casting apparatus according to an embodiment of the present invention, the casting apparatus is disposed on a casting movement path of a continuous casting process, and is arranged so as to cover an area in which at least two co-existence of molten steel, Electromagnetic stirring apparatus; And a control device capable of transmitting a control signal to the electromagnetic stirring device so that the electromagnetic stirring device applies a predetermined electromagnetic field to the cast according to the coagulation profile interlocked with the fluctuating operating conditions of the continuous casting process, A continuous casting apparatus is provided.

Description

[0001] APPARATUS OF CONTINUOUS CASTING [0002]

The present invention relates to a continuous casting apparatus, and more particularly to a continuous casting apparatus having an EMS apparatus.

In general, the process of continuously solidifying molten steel treated with a desired component in a certain form is referred to as continuous casting. The continuous casting machine which continuously performs the continuous casting is produced in the steel making furnace, the molten steel transferred to the ladle is received in the turndish, and supplied to the mold for the continuous casting machine to produce the slab of a certain size.

The conventional continuous casting machine includes a casting mold having a desired shape by cooling the molten steel of the tundish primarily in the mold and cooling the casting piece while moving the casting mold connected to the mold and moving the casting mold do.

That is, the molten steel introduced in the tundish is formed into a slab, a slab, a billet, or a billet having a predetermined width and thickness in the mold. The molten steel is first cooled in the mold, And then cooled by the cooling water injected while moving along the stand, and is conveyed while maintaining the shape formed in the mold.

Related Prior Art Korean Patent Publication No. 2000-0013111 (published on March 23, 2000, entitled "Continuous Casting Method and Continuous Casting Apparatus Used therein") is available.

It is an object of the present invention to provide a continuous casting apparatus capable of controlling an internal structure.

A continuous casting apparatus according to one aspect of the present invention is disclosed. Wherein said continuous casting apparatus is disposed on a casting movement path of a continuous casting process and is arranged to cover an area in which at least two selected from molten steel, a solid-liquid coexisting zone and a solidifying shell coexist together; And a control device capable of transmitting a control signal to the electromagnetic stirring device so that the electromagnetic stirring device applies a predetermined electromagnetic field to the cast according to the coagulation profile interlocked with the fluctuating operating conditions of the continuous casting process.

The continuous casting apparatus may further include a computing device for calculating a coagulation solidification profile linked to the changed operating conditions of the continuous casting process.

In the continuous casting apparatus, the electromagnetic stirring apparatus may be arranged so as to cover an area in which molten steel, a solid-liquid coexisting zone and a solidification shell all coexist.

In the continuous casting apparatus, the electromagnetic stirring apparatus may be an F-EMS (Final Electromagnetic Stirrer) apparatus.

In the continuous casting apparatus, the control apparatus applies a relatively low electromagnetic field when the ratio of molten steel is relatively high and the ratio of the solid-liquid coexisting region is relatively low, and when the ratio of molten steel is relatively low and the ratio of high- It is possible to transmit a control signal to the electromagnetic stirring device, which applies a relatively high electromagnetic field.

In the continuous casting apparatus, the control apparatus applies a relatively low electromagnetic field in the case where the peripheral speed of the continuous casting process is relatively fast, and applies a relatively high electromagnetic field in the case where the peripheral speed of the continuous casting process is relatively slow. To the electromagnetic stirring device.

In the continuous casting apparatus, the variable operating conditions of the continuous casting process may include at least one selected from the group consisting of a peripheral speed, a steel grade, a cooling rate, a number of cooling nozzles and an arrangement.

According to the embodiment of the present invention, it is possible to provide a continuous casting apparatus capable of controlling the internal structure according to the fluctuating operating conditions of the continuous casting process. Of course, the scope of the present invention is not limited by these effects.

1 is a view showing a part of a continuous casting apparatus according to an embodiment of the present invention.
2 is a conceptual diagram illustrating components of a continuous casting apparatus according to an embodiment of the present invention.
3 is a diagram illustrating the relative positions of an electromagnetic stirring apparatus and a coagulation profile interlocked in accordance with the variable operating conditions of a continuous casting process in a continuous casting apparatus according to an embodiment of the present invention.
FIG. 4 is a graph showing the amount of internal molten steel according to the circumferential conditions in the continuous casting apparatus according to an embodiment of the present invention, according to each casting position.
FIG. 5 is a graph showing the thickness of the solidified shell according to the circumferential conditions in the continuous casting apparatus according to an embodiment of the present invention, according to each casting position.
FIG. 6 is a graph showing the size of an applied electromagnetic field according to circumferential conditions in a continuous casting apparatus according to an embodiment of the present invention, for each casting position.

Hereinafter, a slab manufacturing method according to an embodiment of the present invention will be described in detail. The terms used below are appropriately selected terms in consideration of functions in the present invention, and definitions of these terms should be made based on the contents throughout this specification.

FIG. 1 is a view showing a part of a continuous casting apparatus according to an embodiment of the present invention, and FIG. 2 is a conceptual diagram illustrating components of a continuous casting apparatus according to an embodiment of the present invention.

1, the continuous casting machine includes a ladle containing molten steel (M) refined in a steelmaking process, a tundish receiving molten steel through an injection nozzle connected to the ladle, temporarily storing the molten steel, A mold for temporarily storing molten steel temporarily stored in a dish through an immersion nozzle and performing initial solidification in a predetermined shape and a plurality of segments provided at a lower portion of the mold so as to perform a series of molding operations while cooling the non- And a cooling line 290 that is continuously arranged. At this time, a certain region of the lower portion of the cooling line 290 is referred to as a secondary cooling zone. On the other hand, the stopper can adjust the amount of molten steel moving to the immersion nozzle. In the secondary cooling zone, the casting 100, which is primarily cooled in the mold and escapes from the mold, is quickly cooled.

Referring to FIG. 2, it takes some time until the solidified molten steel begins to solidify and completely solidify in the course of cooling out from the mold. In the continuous casting process, since the solidification casting 100 continues to move, the moving distance of the casting slab is considerable until a completely solidified casting slab is obtained. Metallurgical length is sometimes referred to as the distance traveled from the casting to completion of solidification.

An electromagnetic stirring apparatus 230 is disposed on the casting 100 over a region where solidification is almost completed in a continuous casting apparatus according to an embodiment of the present invention. That is, the electromagnetic stirring device 230 is disposed over the region where the molten steel 110, the solid-liquid coexisting zone 120, and the solidification shell 130 coexist. The solid-liquid coexisting region 120 is a region where the liquid phase and the solid phase are coexisted, and the liquid phase (L) having a solid phase fraction of 0 is a region where the liquid phase and the solid phase coexist, whereas the molten steel 110 is a liquid phase, And a solid phase interface S having a solid phase fraction of 1.

When the molten steel 110 solidifies, for example, in a dendrite form, the electromagnetic stirring apparatus 230 includes a liquid phase and shakes the liquid phase in the solid-liquid mixed phase region to break the dendritic structure, When the structure is solidified in the crushed state, the crushed dendrite becomes a new nucleation site and solidification can proceed in an equiaxed form.

In the continuous casting apparatus according to an embodiment of the present invention, the electromagnetic stirring apparatus 230 is an apparatus for controlling the internal structure by applying an electromagnetic field from the outside to generate a rotating current in the internal molten steel, And may be arranged so as to cover an area in which at least two selected from the molten steel (110), the high-coexistence zone (120) and the solidification shell (130) coexist together.

Preferably, the electromagnetic stirring apparatus 230 may be a F-EMS (Final Electromagnetic Stirrer) apparatus, and may be disposed on a region where the liquid molten steel 110 and the solid-liquid rich region 120 exist .

3 is a diagram illustrating the relative positions of an electromagnetic stirring apparatus and a coagulation profile interlocked in accordance with the variable operating conditions of a continuous casting process in a continuous casting apparatus according to an embodiment of the present invention.

FIG. 3 (a) is a case where the main velocity is relatively low, and the point of completion of solidification is formed relatively close to the mold. FIG. 3 (b) shows a case where the velocity of the main velocity is relatively high, 3 (c) is a case in which the main flux is relatively middle speed, and the coagulation completion point is formed between the case of (a) and the case of (b).

On the other hand, the operating conditions of the continuous casting process for determining the solidification completion point of the casting may include at least one selected from the group consisting of the steel grade, the cooling water quantity, the arrangement of the rolls, and the number and arrangement of the cooling nozzles.

In addition, the heat resistance between the mold and the cooling water, the heat resistance of the mold, the thermal resistance between the mold and the mold solvent, the air resistance between the mold and the casting, the thermal resistance of the mold solvent, And operating conditions such as heat radiation resistance may affect the solidification completion point of the cast steel.

Therefore, although the initial mounting position of the electromagnetic stirring apparatus 230 is determined based on the operating conditions of the specific continuous casting process, the position of the electromagnetic stirring apparatus 230 may not be appropriate depending on the change in conditions occurring during operation.

The continuous casting apparatus according to an embodiment of the present invention may control the electromagnetic stirring device 230 to apply a predetermined electromagnetic field to the cast 100 according to the coagulation profile interlocked according to the fluctuating operating conditions of the continuous casting process, This problem can be solved by introducing the control device 220 which can transmit to the stirring device 230.

On the other hand, the coagulation profile interlocked in accordance with the fluctuating operating conditions of the continuous casting process can be grasped through an arithmetic unit 210 which calculates various operating conditions and the like by a method such as simulation. Of course, the solidification profile according to various operating conditions may be provided in the form of a lookup table by making a database in advance.

FIG. 4 is a graph showing the amount of internal molten steel according to the circumferential conditions in the continuous casting apparatus according to an embodiment of the present invention, according to each casting position. Referring to FIG. 4, it can be seen that the amount of internal molten steel is relatively large at the same casting position as the casting speed increases.

FIG. 5 is a graph showing the thickness of the solidified shell according to the circumferential conditions in the continuous casting apparatus according to an embodiment of the present invention, according to each casting position. Referring to FIG. 5, it can be seen that the coagulating shell thickness is relatively thin at the same casting position as the casting speed increases.

FIG. 6 is a graph showing the size of an applied electromagnetic field according to circumferential conditions in a continuous casting apparatus according to an embodiment of the present invention, for each casting position. Referring to FIG. 6, it can be seen that the applied current value of the electromagnetic stirring apparatus can be smaller at the same casting position as the main casting speed increases.

In consideration of these results, in the continuous casting apparatus according to the embodiment of the present invention, when the ratio of the molten steel 110 is relatively high and the ratio of the high-coexistence zone 120 is relatively low, A low electromagnetic field is applied and a control signal can be transmitted to the electromagnetic stirring device 230 that applies a relatively high electromagnetic field when the proportion of the molten steel 110 is relatively low and the proportion of the solid solution coexisting region 120 is relatively high have.

Meanwhile, in the continuous casting apparatus according to an embodiment of the present invention, the controller 220 applies a relatively low electromagnetic field when the ratio of the molten steel 110 is relatively high and the ratio of the solidifying shell 130 is relatively low A relatively high electromagnetic field may be applied to the electromagnetic stirring device 230 when the proportion of the molten steel 110 is relatively low and the proportion of the solidifying shell 130 is relatively high.

Further, in the continuous casting apparatus according to an embodiment of the present invention, the controller 220 applies a relatively low electromagnetic field in the case where the peripheral speed of the continuous casting process is relatively fast, and when the peripheral speed of the continuous casting process is relatively slow, To the electromagnetic stirring device 230, a control signal for applying a high electromagnetic field to the electromagnetic stirring device 230. [

It is to be understood that the invention includes various modifications and equivalent embodiments that can be derived from the disclosed embodiments as well as those of ordinary skill in the art to which the present invention pertains. Accordingly, the technical scope of the present invention should be defined by the following claims.

100: Casting
110: molten steel
120: High cost coexistence station
130: Solidification shell
210:
220: Control device
230: electromagnetic stirrer

Claims

An electromagnetic stirring device disposed on a casting movement path of the continuous casting process, the electromagnetic stirring device being disposed so as to cover an area in which at least two of the molten steel, the coexisting solid phase and the solidifying shell coexist together; And
A control device capable of transmitting a control signal to the electromagnetic stirring device so that the electromagnetic stirring device applies a predetermined electromagnetic field to the cast according to the coagulation profile interlocked with the fluctuating operating conditions of the continuous casting process;
And a continuous casting apparatus.

The method according to claim 1,
Wherein the electromagnetic stirring apparatus is arranged to cover an area in which molten steel, a solid-liquid coexisting zone and a solidification shell all coexist.

The method according to claim 1,
Wherein the electromagnetic stirring apparatus is a F-EMS (Final Electromagnetic Stirrer) apparatus.

The method according to claim 1,
The control device applies a relatively low electromagnetic field when the ratio of the molten steel is relatively high and the ratio of the solid-liquid coexisting region is relatively low. When the proportion of the molten steel is relatively low and the ratio of the solid-liquid coexisting region is relatively high, And transmits a control signal to the electromagnetic stirring device, to which an electromagnetic field is applied.

The method according to claim 1,
The control device transmits a control signal to the electromagnetic stirring device, which applies a relatively low electromagnetic field when the peripheral speed of the continuous casting process is relatively fast and applies a relatively high electromagnetic field when the peripheral speed of the continuous casting process is relatively slow Lt; / RTI >

The method according to claim 1,
Wherein the variable operating conditions of the continuous casting process include at least one selected from the group consisting of a peripheral speed, a steel grade, a cooling water quantity, and a number and arrangement of cooling nozzles.