Title of Invention: Casting Equipment and Casting Method
technical field
[One]
The present invention relates to a casting facility and a casting method, and more particularly, to a casting facility and a casting method capable of improving the quality of a product by controlling the flow of the melt to secure the cleanliness of the melt.
background
[2]
In general, the continuous casting process injects molten steel into a mold having a certain internal shape, and continuously draws the solid reacted slab in the mold to the lower side of the mold to manufacture slabs, blooms, billets, beam blanks, etc. of various shapes. can do. The surface quality and internal quality of the cast steel manufactured in this way are affected by various factors, and in particular, the surface quality of the cast steel is greatly affected by the flow of molten steel in the mold.
[3]
When the melt is injected into the mold using the submerged nozzle in the continuous casting process, the melt discharged from the outlet of the submerged nozzle forms a jet and flows in the width direction of the mold. The melt flowing in the width direction of the mold collides with the inner surface of the mold, for example, the inner surface of the short side plate to form an upward flow and a part to form a downward flow. And the upward flow moves toward the center of the mold, for example, in the vicinity of the hot water surface of the melt, to which the submerged nozzle is installed. In this way, the melt moving toward the center of the mold collides with the melt moving in opposite directions and the immersion nozzle to form a vortex near the molten water surface around the immersion nozzle, thereby destabilizing the flow of the molten water. At this time, the faster the flow rate of the upward flow is, the more unstable the flow of the molten material is on the molten material, so there is a problem in that heterogeneous materials such as mold slag or mold flux located on the upper portion of the molten material are mixed into the melt.
[4]
In addition, the downflow flows downward along the edge of the mold to form a secondary upward flow that rises from the center of the mold. In this case, the inclusions contained in the molten steel may be removed by moving in the casting direction along the downward flow, floating along the secondary upward flow, and flowing into the mold slag or the mold flux. However, the movement distance of the inclusions varies according to the flow rate of the downflow, and when the flow rate of the downflow is fast, there is a problem in that the inclusions penetrate into the solidification cell and cause surface defects of the subsequently manufactured slab.
[5]
In order to solve this problem, a method of controlling the flow of molten steel in the mold by installing a magnetic field generator in the mold is used. In this way, by controlling the upward flow in the vicinity of the molten steel molten steel, the inflow of the mold flux into the molten steel is suppressed, and by controlling the downward flow at the bottom of the immersion nozzle, the movement distance of inclusions is controlled, thereby suppressing the occurrence of surface defects of the cast steel. are doing However, in the process of controlling the downflow, the formation of the secondary upflow caused by the downflow is also suppressed. For this reason, there is a problem in that the inclusions moving in the casting direction along the downflow are not properly floated and remain in the molten steel, thereby still reducing the quality of the cast steel.
[6]
(Prior Document 1) KR10-1176816 B
[7]
(Prior Document 2) JP4411945 B
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[8]
The present invention provides a casting equipment and a casting method capable of controlling the flow of a melt.
[9]
The present invention provides a casting equipment and a casting method capable of smoothly removing inclusions contained in a melt and improving the quality of a product by suppressing mixing of different substances into the melt.
means of solving the problem
[10]
A casting facility according to an embodiment of the present invention is a casting facility for casting a slab,
[11]
a mold providing a space for accommodating the melt therein; a nozzle provided on the mold to supply the melt to the mold; a static magnetic field generator provided outside the mold in the width direction to control directions of magnetic fields in different directions at both edge portions in the width direction of the mold; and a control unit capable of controlling the operation of the static magnetic field generator.
[12]
The mold includes a pair of long-side plates spaced apart from each other, and a pair of short-side plates connecting both sides of the pair of long-side plates, respectively, and the static magnetic field generator is spaced apart from the center in the width direction of the mold. a plurality of static magnetic field generators provided at a lower portion of the nozzle in the width direction of the long side plate; and a first current supply capable of supplying a direct current to the plurality of static magnetic field generators so as to form a magnetic field passing through both sides of the nozzle in the thickness direction of the mold in the width direction of the mold.
[13]
Each of the plurality of static magnetic field generators may include: a core extending along a portion of a width direction of the long side plate and disposed to be spaced apart from each other; and a coil wound on the outside of the core.
[14]
The plurality of static magnetic field generators may include: a first static magnetic field generator; a second static magnetic field generator disposed to be spaced apart from one side of the first static magnetic field generator such that the nozzle is disposed between the first static magnetic field generator; a third static magnetic field generator disposed to face the second static magnetic field generator; and a fourth static magnetic field generator disposed to be spaced apart from one side of the third static magnetic field generator such that the nozzle is disposed between the third static magnetic field generator and disposed to face the first static magnetic field generator, and , the first current supplier forms opposite polarities in a direction opposite to each other in the thickness direction of the mold, and forms opposite polarities in a width direction of the mold, the first static magnetic field generator and the second static electricity supply A direct current may be supplied to the field generator, the third static magnetic field generator, and the fourth static magnetic field generator.
[15]
The first static magnetic field generator and the second static magnetic field generator are spaced apart from each other by a first distance, the third static magnetic field generator and the fourth static magnetic field generator are spaced apart by a second distance, and the first static field generator and the second static magnetic field generator are spaced apart from each other by a second distance. The distances may have the same size.
[16]
When the total width of the slab is 100, the first distance and the second distance may be 4 to 36.
[17]
At least one of the first static magnetic field generator, the second static magnetic field generator, the third static magnetic field generator, and the fourth static magnetic field generator may be provided to be movable along a width direction of the mold.
[18]
a first connection core for connecting the first static magnetic field generator and the second static magnetic field generator; and a second connection core configured to connect the third static magnetic field generator and the fourth static magnetic field generator.
[19]
The static magnetic field generator may form a magnetic field that rotates in a circumferential direction of the mold.
[20]
and a moving magnetic field generator provided on an upper portion of the static magnetic field generator and capable of forming a moving magnetic field to control the flow of the melt, wherein the controller moves the moving magnetic field to adjust at least one of the strength and direction of the moving magnetic field The operation of the magnetic field generator can be controlled.
[21]
The moving magnetic field generator may include a plurality of moving magnetic field generators capable of generating a moving magnetic field from both sides of the nozzle in a width direction of the mold.
[22]
The moving magnetic field generator may be disposed in parallel with the static magnetic field generator, and may control the flow of the melt in different directions from the static magnetic field generator.
[23]
A casting method according to an embodiment of the present invention includes a process of injecting a melt into a mold using a nozzle; controlling the flow of the melt in the longitudinal direction of the mold by forming a static field applied region and a static magnetic field unapplied region in the width direction of the mold; and the process of drawing the slab; may include.
[24]
Before the process of injecting the melt, the process of arranging the nozzle at the center in the width direction of the mold, and the process of controlling the flow of the melt, includes a region where a static magnetic field is not applied at the center in the width direction of the mold. and forming the static magnetic field applied area on both sides of the static magnetic field unapplied area.
[25]
The process of controlling the flow of the melt may include forming the static field applied region and the static magnetic field unapplied region below the nozzle.
[26]
The process of controlling the flow of the melt includes forming a static magnetic field along a thickness direction of the mold, and the forming of the static field application region includes a magnetic field direction from both sides of the nozzle in a width direction of the mold. It may include a process of forming a static field so that these are formed in opposite directions.
[27]
The process of controlling the flow of the melt may include forming the static magnetic field unapplied region in a portion of a central portion in a width direction of the mold in which the nozzle is disposed.
[28]
The process of controlling the flow of the melt may include controlling the range of the static magnetic field applied region so that the static magnetic field unapplied region has a magnetic field of 0 to 100 Gauss.
[29]
The process of controlling the flow of the melt may include the process of adjusting the distance between the static field application areas according to the width of the cast steel.
[30]
In the process of controlling the flow of the melt, the static magnetic field application regions are formed on both edges of the mold in the width direction to reduce the flow velocity of the downward flow of the melt, and the static magnetic field is not applied between the static magnetic field application regions. It may include forming a region to form an upward flow of the melt.
[31]
The process of controlling the flow of the melt may further include controlling the flow of the melt in the width direction of the mold by forming a moving magnetic field applied region and a moving magnetic field non-applied region in the width direction of the mold.
[32]
The process of controlling the flow of the melt in the width direction of the mold may include forming a moving magnetic field applied region and a moving magnetic field non-applied region between the molten water surface and the lower end of the nozzle.
[33]
The forming of the moving magnetic field application region may include forming a moving magnetic field in the width direction of the mold at both sides of the nozzle in the width direction of the mold.
[34]
The forming of the moving magnetic field application region may include adjusting at least one of a magnetic field strength and a direction of the moving magnetic field.
Effects of the Invention
[35]
According to an embodiment of the present invention, it is possible to locally control the flow of the melt contained in the vessel. That is, it is possible to selectively control the flow of the melt in the longitudinal direction of the mold by selectively applying a static magnetic field in the width direction of the mold. Accordingly, it is possible to reduce the distance that the inclusions contained in the melt move downward along the melt, and at the same time facilitate the upward movement, thereby suppressing deterioration in product quality due to the inclusions. In addition, by forming a moving magnetic field in the width direction of the mold to control the flow of the melt in the vicinity of the melt surface, it is possible to suppress mixing of different materials such as mold flux or mold slag into the melt. Through this, the cleanliness of the melt can be secured and the quality of the product manufactured using the melt can be improved.
Brief description of the drawing
[36]
1 is a perspective view of a casting facility according to an embodiment of the present invention.
[37]
Fig. 2 is a cross-sectional view of the casting plant taken along line AA' shown in Fig. 1;
[38]
3 is a view for explaining the principle of controlling the flow of the melt using a static magnetic field generator.
[39]
4 is a cross-sectional view of a casting facility according to a modified example of the present invention.
[40]
5 is a view showing a state of controlling the flow of the melt by the casting method according to an embodiment of the present invention.
[41]
6 is a view showing the flow analysis results of the secondary upward flow in the mold according to whether or not a static magnetic field is not applied in the width direction of the mold.
[42]
Fig. 7 is a sectional view of the casting plant taken along the line BB' shown in Fig. 1;
[43]
8 is a view showing an example of controlling the flow of a melt using a moving magnetic field generator.
Modes for carrying out the invention
[44]
Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art completely It is provided to inform you. In the description, the same reference numerals are assigned to the same components, and the sizes of the drawings may be partially exaggerated in order to accurately describe the embodiments of the present invention, and the same reference numerals refer to the same elements in the drawings.
[45]
1 is a perspective view of a casting facility according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of the casting facility taken along line AA' shown in FIG. 1 .
[46]
1 and 2, the casting equipment according to an embodiment of the present invention, a mold 100 that provides a space for accommodating the melt therein, and at least a part to supply the melt to the mold 100 The nozzle 130 provided to be inserted into the mold 100, and the direction of the magnetic field at both edges in the width direction of the mold 100 to control in different directions, outside the width direction of the mold 100 It may include the provided static magnetic field generating unit 200 and the control unit 400 capable of controlling the operation of the static magnetic field generating unit 200 .
[47]
The mold 100 may include a plurality of plates 110 and 120 for providing a space for accommodating the melt, for example, molten steel therein. In this case, the plurality of plates 110 and 120 may include a long side plate 110 and a short side plate 120 .
[48]
The long side plate 110 , for example, the first long side plate 111 and the second long side plate 113 are disposed to face each other and spaced apart from each other, and the short side plate 120 , for example, the first short side plate 121 and the second short side plate 113 . The plate 123 may be disposed to contact both sides of the first long side plate 111 and the second long side plate 113 to form a space capable of accommodating the melt therein. In this case, the upper and lower portions of the mold 100 may be opened, and the long-side plate 110 and the short-side plate 120 may be in close contact with each other so that the melt does not flow out to the contact portion.
[49]
Here, a horizontal length of the long side plate 110 is referred to as a width of the long side plate 110 , and a direction thereof is referred to as a width direction of the long side plate 110 . In this case, the width direction of the long side plate 110 may mean the width direction of the mold 100 . In addition, the vertical length of the long side plate 110 is referred to as the length of the long side plate 110 , and the direction is referred to as the longitudinal direction of the long side plate 110 . In this case, the longitudinal direction of the long side plate 110 may mean the longitudinal direction of the mold 100 or the drawing direction of the cast slab. In addition, the horizontal length of the short side plate 120 is referred to as the width of the short side plate 120 , and the direction is referred to as the width direction of the short side plate 120 . In this case, the width direction of the short-side plate 120 may mean a thickness direction of the mold 100 .
[50]
A flow path (not shown) through which a cooling medium moves is formed inside the long side plate 110 and the short side plate 120 , and the melt injected into the mold 100 is cooled by the cooling medium moving along the flow path. can be Accordingly, the molten material may be solidified from a portion in contact with the inner surface of the mold 100 and cast into a solidification cell or slab, and may be drawn into the lower portion of the mold 100 .
[51]
The nozzle 130 may be provided on the mold 100 to inject the melt into the mold 100 . The nozzle 130 is disposed so that at least a portion, for example, a lower portion, is inserted into the mold 100 , and the melt accommodated in a tundish (not shown) provided on the mold 100 can be injected into the mold 100 . . The nozzle 130 may include a nozzle body 132 having an inner portion through which the melt can move, and a discharge port 134 through which the melt can move from the inner portion to the outside, that is, to the mold 100 . At this time, the nozzle body 132 has an open upper portion and a closed lower end, and an inner portion (not shown) may be formed therein to form a passage through which the melt can move. In addition, at least two or more, for example, two or four, may be formed on the lower side of the nozzle body 132 to discharge the melt into the mold 100 . In this case, the discharge port 134 may be formed on the lower side of the nozzle body 132 opposite to the short side plate 120 so as to discharge the melt in the width direction of the mold 100 .
[52]
The static magnetic field generator 200 may be provided outside the mold 100 in the width direction to apply a magnetic field, for example, a static magnetic field to the melt. In this case, the static magnetic field generator 200 may be provided below the lower end of the nozzle 130 to control the downward flow of the melt discharged to the discharge port 134 . In addition, the static magnetic field generator 200 may be formed at both edges in the width direction of the mold 100 in which the downward flow is formed, thereby forming a static magnetic field application region. The static magnetic field generator 200 may apply a static magnetic field in the width direction of the mold 100 to reduce the flow rate of a downflow of the melt formed at the edge of the mold 100 in the width direction. Here, the static field is a magnetic field formed by using a DC power source in a magnetic field generator, and may serve to reduce the flow rate of the fluid by suppressing the flow or overall behavior of the fluid in the magnetic field. As such, when a static magnetic field is applied to the mold 100 by the static magnetic field generator 200 , the movement of the downflow is suppressed by the static field, and the flow rate of the downflow may be reduced. Accordingly, the movement distance of the inclusions in the downward direction may be shortened, and thus the penetration depth of the inclusions in the melt may be reduced.
[53]
Conventionally, a method of controlling downflow by installing a static magnetic field generator in a mold has been used. In this case, since the static field generator was installed in the mold to apply the static field along the entire width direction of the mold, the flow rate of the downflow could be reduced. However, the flow of the melt is suppressed by the static magnetic field formed along the entire width direction of the mold, and the secondary upward flow is also reduced, so there is a problem in that it is difficult to remove the inclusions contained in the melt by floating upward.
[54]
Accordingly, in the present invention, a static magnetic field applied region and a static magnetic field non-applied region are selectively formed along the width direction of the mold 100 using the static magnetic field generator 200 . and to minimize the influence of the magnetic field in the non-static field, to form a secondary upward flow.
[55]
The static magnetic field generator 200 may form a static magnetic field so that the directions of the magnetic fields on both sides in the width direction of the mold 100 are different from each other in the thickness direction of the mold 100 , for example, opposite directions. Accordingly, the static magnetic field generator 200 forms static field application regions at both edges in the width direction of the mold 100 , and the strength of the magnetic field formed in the static field application region in the central portion in the width direction of the mold 100 is offset. A region in which a static magnetic field is not applied may be formed. Accordingly, since the inclusions having a reduced penetration depth in the static magnetic field applied region can easily float upward by the secondary upward flow formed in the static magnetic field unapplied region, defects on the surface of the cast steel caused by the inclusions can be suppressed.
[56]
The static magnetic field generator 200 can reduce the flow velocity of a downflow formed in the longitudinal direction of the mold 100 at both edges in the width direction of the mold 100 in which the static field application region is formed, and the static magnetic field is not applied. In the central portion in the width direction of the mold 100 in which the region is formed, the flow rate of the secondary upward flow formed in the longitudinal direction of the mold 100 may be increased or the secondary upward flow may be smoothly formed.
[57]
Here, the static magnetic field application region is a region where a static magnetic field or a magnetic field is formed by the static magnetic field generator 200, and may mean a region to which a static magnetic field or magnetic field of a strength sufficient to apply the flow of the melt is applied. there is. In addition, the static field non-applied region may mean a region to which a static or magnetic field having an intensity that does not affect the flow of the melt is applied, or to which a static or magnetic field is not applied at all. For example, the static field non-applied region may mean a region to which a static magnetic field or a magnetic field of about 0 to 100 Gauss is applied.
[58]
Referring to FIG. 2 , the static magnetic field generator 200 includes a plurality of static magnetic field generators 210 , 220 , 230 , 240 provided in the width direction of the long side plate 110 below the lower end of the nozzle 130 , A first current supply 250 capable of supplying a DC current to the plurality of static magnetic field generators 210 , 220 , 230 , and 240 may be included.
[59]
The plurality of static magnetic field generators 210, 220, 230 and 240 includes a first static magnetic field generator (210) such that a nozzle 130 is disposed between the first static magnetic field generator 210 and the first static magnetic field generator 210 Between the second static magnetic field generator 220 disposed to be spaced apart from 210 and the third static magnetic field generator 230 and the third static magnetic field generator 230 disposed to face the second static magnetic field generator 220 The nozzle 130 may be disposed to be spaced apart from the third static magnetic field generator 230 and may include a fourth static magnetic field generator 240 disposed to face the first static magnetic field generator 210 . The first static magnetic field generator 210 and the second static magnetic field generator 220 may be disposed to be spaced apart from each other on the outer surface of the first long side plate 111 , and the third static magnetic field generator 230 and the fourth static magnetic field generator 240 may be disposed on the outer surface of the second long side plate 113 to be spaced apart from each other. At this time, the separation distance D between the first static magnetic field generator 210 and the second static magnetic field generator 220 , for example, the first distance, and the third static magnetic field generator 230 and the fourth static magnetic field generator 240 . The separation distance D, for example, the second distance may have the same size. This is so that the static magnetism non-applied region is formed at the center in the width direction of the mold 100 . The first distance and the second distance may be changed according to the width of the cast slab, and when the total width of the slab is 100, the first distance and the second distance may be adjusted in the range of 4 to 36. Alternatively, when the total width of the cast slab is 100, the first distance and the second distance may be adjusted in the range of 10 to 25 or 15 to 20. At this time, if the first distance and the second distance are too short than the suggested range, it is not possible to sufficiently secure a space for the secondary upward flow to be formed. Accordingly, there is a problem in that it is difficult to sufficiently remove the inclusions contained in the melt because the secondary upward flow is hardly formed or is formed in a relatively narrow area even if the secondary upward flow is formed. On the other hand, when the first distance and the second distance are excessively longer than the suggested range, the downflow with reduced flow velocity at both edges in the width direction of the mold 100 does not move sufficiently to the center of the mold 100 , and thus Accordingly, there is a problem in that the flow rate of the secondary upward flow is reduced, making it difficult to float the inclusions upward.
[60]
Accordingly, the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 are provided to be movable along the width of the mold 100 . By doing so, the inclusions contained in the melt can be efficiently removed by appropriately adjusting the first distance and the second distance according to the width of the cast steel. At this time, the first distance and the second distance may be affected by the casting speed, for example, when the width of the slab is 1100 mm or less and the casting speed is 0.7 to 2.8 m/min, the first distance and the second distance are 50 to It can be adjusted to about 250mm. In addition, when the width of the cast slab is 1100 to 1500 mm, and the casting speed is 0.7 to 2.8 m/min, the first distance and the second distance can be adjusted to about 100 to 350 mm, and the width of the cast slab is 1500 to 1900 mm, and , when the casting speed is 0.7 to 2.8 m/min, the first distance and the second distance may be adjusted to about 100 to 500 mm.
[61]
First, the first static magnetic field generator 210 is provided to be biased toward one side of the first long side plate 111 , and the second static magnetic field generator 220 is spaced apart from the first static magnetic field generator 210 , and the first long side plate 111 . It may be provided to be biased toward the other side of the plate 111 . In this case, the first static magnetic field generator 210 may include a first core 212 and a first coil 214 wound outside the first core 212 . The second static magnetic field generator 220 may include a second core 222 and a second coil 224 wound on the outside of the second core 222 . Here, one side of the mold 100 or one side of the long side plate 110 means the direction in which the first short side plate 121 is located, and the other side of the mold 100 or the other side of the long side plate 110 is the second short side plate. It may mean the direction in which (123) is located.
[62]
The first core 212 and the second core 222 may be provided outside the mold 100 to be spaced apart from each other in the width direction of the mold 100 . The first core 212 and the second core 222 may be formed in a plate shape extending in one direction. For example, the first core 212 and the second core 222 may be formed in a plate shape in which the length in the width direction of the mold 100 is longer than the length in the width direction of the mold 100 . The first core 212 and the second core 222 may be arranged in a line on the outer surface of the first long side plate 111 to extend along a portion of the width direction of the first long side plate 111 . At this time, the first core 212 and the second core 222 may be disposed to be spaced apart from each other at the center in the width direction of the mold 100 in which the nozzle 130 is disposed so that the nozzle 130 may be disposed therebetween. can
[63]
In addition, the first coil 214 may be wound outside the first core 212 in a direction in which the first core 212 extends, for example, in the width direction of the mold 100 . In addition, the second coil 224 may be wound on the outside of the second core 222 in a horizontal direction in a direction in which the second core 222 extends, for example, in a width direction of the mold 100 .
[64]
In addition, the third static magnetic field generator 230 is provided so as to be biased toward the other side of the second long side plate 113 , and the fourth static magnetic field generator 240 is spaced apart from the third static magnetic field generator 230 and the second long side plate 113 . It may be provided to be biased toward one side of the plate 113 . In this case, the third static magnetic field generator 230 may be disposed to face the second static magnetic field generator 220 , for example, to face it, and the fourth static magnetic field generator 240 is connected to the first static magnetic field generator 210 and 210 . They can be placed facing each other. The third static magnetic field generator 230 may include a third core 232 and a third coil 234 wound on the outside of the third core 232 . The fourth static magnetic field generator 240 may include a fourth core 242 and a fourth coil 244 wound outside the fourth core 242 . The third core 232 and the fourth core 242 may be provided outside the mold 100 to be spaced apart from each other in the width direction of the mold 100 . The third core 232 and the fourth core 242 may be arranged in a line on the outer surface of the second long side plate 113 to extend along a portion of the width direction of the second long side plate 113 . At this time, the third core 232 and the fourth core 242 may be disposed to be spaced apart from each other at the center in the width direction of the mold 100 in which the nozzle 130 is disposed so that the nozzle 130 may be disposed therebetween. can
[65]
In addition, the third coil 234 may be wound on the outside of the third core 232 in the width direction of the mold 100 in the direction in which the third core 232 extends. In addition, the fourth coil 244 may be wound on the outside of the fourth core 242 in the width direction of the mold 100 , which is the direction in which the fourth core 242 extends.
[66]
The first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 may be electrically connected to the first current supply 250 . . The first current supply 250 may supply a direct current to the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 . . The first current supply 250 is controlled by the controller 400 , the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 . ) can be supplied with direct current at the same time or selectively. The first current supply 250 includes a first static magnetic field generator 210 , a second static magnetic field generator 220 , a third static magnetic field generator 230 and a fourth so that the magnetic field is formed in the thickness direction of the mold 100 . A direct current may be supplied to the static magnetic field generator 240 . In this case, the first current supply 250 may supply a direct current so that magnetic fields are formed in opposite directions to each other at the center, for example, both sides of the nozzle 130 in the width direction of the mold 100 . That is, in the first current supply 250 , the magnetic field direction is formed from the first static magnetic field generator 210 to the fourth static magnetic field generator 240 on one side of the mold 100 , and the magnetic field direction from the other side of the mold 100 . The first static magnetic field generator 210, the second static magnetic field generator 220, the third static magnetic field generator 230, and the fourth static magnetic field generator 210 are formed from the third static magnetic field generator 230 toward the second static magnetic field generator 220. A direct current may be supplied to the static magnetic field generator 240 . At this time, the control unit 400 controls the strength or strength of the magnetic field, the first static magnetic field generator 210,
[67]
Here, the direction of the magnetic field formed on one side of the nozzle 130 in the width direction of the mold 100 , for example, one side of the mold 100 is referred to as a first direction, and the other side of the nozzle 130 in the width direction of the mold 100 . , for example, the direction of the magnetic field formed on the other side of the mold 100 is referred to as a second direction. For example, the direction of the magnetic field formed between the first static magnetic field generator 210 and the fourth static magnetic field generator 240 is referred to as a first direction, and the direction between the second static magnetic field generator 220 and the third static magnetic field generator 230 is referred to as a first direction. The direction of the formed magnetic field is referred to as a second direction. In this case, the first direction and the second direction may be opposite to each other. And the direction facing the mold 100 in the first core 212 , the second core 222 , the third core 232 , and the fourth core 242 is referred to as one side, and faces the outside of the mold 100 . The direction is called the other side. Accordingly, the first current supply 250 may supply a direct current so that one side of the first core 212 and one side of the fourth core 242 facing each other have opposite polarities. In addition, the first current supply 250 may supply a direct current so that one side of the second core 222 and one side of the third core 232 facing each other have opposite polarities. At this time, the first current supply 250 may supply a direct current so that one side of the first core 212 and one side of the second core 222 have opposite polarities, and one side of the third core 232 and the first side of the third core 232 . A direct current may be supplied so that one side of the four cores 242 has opposite polarities.
[68]
For example, in the first current supply 250 , one side of the first core 212 and one side of the third core 232 have an N pole, and one side of the second core 222 and one side of the fourth core 242 are connected to each other. Direct current can be supplied to have an S pole. In this case, when a direct current is formed in each of the static magnetic field generators 210 , 220 , 230 and 240 from the first current supply 250 , a static magnetic field is formed in each of the static magnetic field generators 210 , 220 , 230 and 240 . can be In each of the static magnetic field generators 210 , 220 , 230 , and 240 , a static magnetic field with a magnetic field direction from the S pole to the N pole may be formed. At this time, the static magnetic field generated by the first static magnetic field generator 210 has a magnetic field direction from the other side of the first core 212 to one side of the first core 212 , and the static magnetic field generated by the fourth static magnetic field generator 240 is a magnetic field The direction may be formed such that one side of the fourth core 242 faces the other side of the fourth core 242 . A magnetic field having a first direction, for example, from the first static magnetic field generator 210 to the fourth static magnetic field generator 240 may be formed on one side of the mold 100 . And the static magnetic field generated from the third static magnetic field generator 230 has a magnetic field direction from the other side of the third core 232 to one side of the third core 232 , and the static magnetic field generated from the second static magnetic field generator 220 has a magnetic field direction One side of the second core 222 may be formed to face the other side of the second core 22 . A magnetic field having a second direction, for example, from the third static magnetic field generator 230 to the second static magnetic field generator 220 may be formed on one side of the mold 100 . Here, the first direction is from the first static magnetic field generator 210 to the fourth static magnetic field generator 240, The second direction is described as meaning the third static magnetic field generator 230 to the second static magnetic field generator 220, but in the first current supply 250, the first static magnetic field generator 210 and the second static magnetic field The first direction and the second direction may be changed according to a state in which DC current is supplied to the generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 . However, even in this case, the first direction and the second direction may be opposite to each other.
[69]
[70]
3 is a view for explaining the principle of controlling the flow of the melt using the static magnetic field generator.
[71]
First, the melt may be injected into the mold 100 using the nozzle 130 . Before injecting the melt into the mold 100 , the nozzle 130 may be positioned at the center in the width direction of the mold 100 . And by using the static magnetic field generator 200 to form a static magnetic field applied region and a static magnetic field unapplied region in the width direction of the mold 100 to control the flow of the melt in the longitudinal direction of the mold 100, the slab can be drawn out. can In this case, the process of forming the static magnetic field applied region and the static magnetic field unapplied region in the width direction of the mold 100 may be performed before the melt is injected into the mold 100 , or after the melt is injected into the mold 100 . It may be performed, or it may be performed simultaneously with the injection of the melt into the mold 100 .
[72]
The flow of the melt can be controlled as follows.
[73]
Referring to FIG. 3 , a first static magnetic field generator 210 , a second static magnetic field generator 220 , a third static magnetic field generator 230 , and a fourth static magnetic field generator 240 through the first current supply 250 . When a DC current is supplied to there is. In this case, the first static magnetic field generator 210 and the third static magnetic field generator 230 disposed to be shifted from each other about the nozzle 130 may have the same polarity, and the second static magnetic field generator 210 disposed to be shifted from each other ( 220) and the fourth static magnetic field generator 240 may have the same polarity. For example, one side of the first core 212 and one side of the third core 232 form the same polarity, for example, an N pole, and one side of the second core 222 and one side of the fourth core 242 have the same polarity , for example, an S pole may be formed. In addition, the static magnetic field formed by each of the static field generators 210 , 220 , 230 , and 240 has a magnetic field direction from the S pole to the N pole along each of the cores 212 , 222 , 232 , and 242 . At this time, the magnetic field around each of the cores 212, 222, 232, 242 also has a magnetic field direction from the S pole to the N pole. A magnetic field may be formed in the thickness direction of the mold 100 by the direction. In addition, the magnetic field strength gradually decreases as the magnetic field moves away from each of the cores 212 , 222 , 232 , and 242 . Accordingly, a magnetic field is canceled between the first static magnetic field generator 210 and the fourth static magnetic field generator 240 facing each other, so that a section in which no magnetic field is applied or a very weak magnetic field strength may be formed. This is because one side of the first core 212 and one side of the fourth core 242 facing each other have opposite polarities. In addition, even between the second static magnetic field generator 220 and the third static magnetic field generator 230 facing each other, a section in which no magnetic field is applied or the magnetic field strength is very weak may be formed. This is because one side of the second core 222 and one side of the third core 232 facing each other have opposite polarities. Also, no magnetic field is applied or a magnetic field is applied between the first static magnetic field generator 210 and the second static magnetic field generator 220 and between the third static magnetic field generator 230 and the fourth static magnetic field generator 240 adjacent to each other. A section in which the intensity is very weak may be formed. Accordingly, between the static fields generated by the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 , for example, the mold 100 is formed. A section in which no magnetic field is applied to the center in the thickness direction and the center in the width direction of the mold 100 in the thickness direction or in which the magnetic field strength is very weak, that is, a region in which a static magnetic field is not applied may be formed. Here, that the magnetic field is not applied or the magnetic field strength is very weak may mean that the magnetic field strength is 0 to 100 Gauss or less. Even between the second static magnetic field generator 220 and the third static magnetic field generator 230 facing each other, a section in which no magnetic field is applied or a very weak magnetic field strength may be formed. This is because one side of the second core 222 and one side of the third core 232 facing each other have opposite polarities. Also, no magnetic field is applied or a magnetic field is applied between the first static magnetic field generator 210 and the second static magnetic field generator 220 and between the third static magnetic field generator 230 and the fourth static magnetic field generator 240 adjacent to each other. A section in which the intensity is very weak may be formed. Accordingly, between the static fields generated by the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 , for example, the mold 100 is formed. A section in which no magnetic field is applied to the center in the thickness direction and the center in the width direction of the mold 100 in the thickness direction or in which the magnetic field strength is very weak, that is, a region in which a static magnetic field is not applied may be formed. Here, that the magnetic field is not applied or the magnetic field strength is very weak may mean that the magnetic field strength is 0 to 100 Gauss or less. Even between the second static magnetic field generator 220 and the third static magnetic field generator 230 facing each other, a section in which no magnetic field is applied or a very weak magnetic field strength may be formed. This is because one side of the second core 222 and one side of the third core 232 facing each other have opposite polarities. Also, no magnetic field is applied or a magnetic field is applied between the first static magnetic field generator 210 and the second static magnetic field generator 220 and between the third static magnetic field generator 230 and the fourth static magnetic field generator 240 adjacent to each other. A section in which the intensity is very weak may be formed. Accordingly, between the static fields generated by the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 , for example, the mold 100 is formed. A section in which no magnetic field is applied to the center in the thickness direction and the center in the width direction of the mold 100 in the thickness direction or in which the magnetic field strength is very weak, that is, a region in which a static magnetic field is not applied may be formed. Here, that the magnetic field is not applied or the magnetic field strength is very weak may mean that the magnetic field strength is 0 to 100 Gauss or less. For example, a section in which no magnetic field is applied to the center in the thickness direction of the mold 100 and the center in the width direction of the mold 100 or in which the magnetic field strength is very weak, that is, a region in which a static magnetic field is not applied may be formed. Here, that the magnetic field is not applied or the magnetic field strength is very weak may mean that the magnetic field strength is 0 to 100 Gauss or less. For example, a section in which no magnetic field is applied to the center in the thickness direction of the mold 100 and the center in the width direction of the mold 100 or in which the magnetic field strength is very weak, that is, a region in which a static magnetic field is not applied may be formed. Here, that the magnetic field is not applied or the magnetic field strength is very weak may mean that the magnetic field strength is 0 to 100 Gauss or less.
[74]
In this way, the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 are installed on the outside of the mold 100 , so that the first A static magnetic field application region is formed in an area where the static magnetic field generator 210, the second static magnetic field generator 220, the third static magnetic field generator 230, and the fourth static magnetic field generator 240 are disposed, and the first static magnetic field A static magnetic field unapplied region may be selectively formed between the generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator and the fourth static magnetic field generator 240 . Therefore, in the region to which a static magnetic field is applied, the flow velocity of the downflow of the melt can be reduced by using the magnetic field, and in the region where the static magnetic field is not applied, the effect of the magnetic field can be minimized to smoothly form a secondary upward flow. At this time, the width of the non-static field can be adjusted according to the width of the cast slab. As described above, it is possible to smoothly form a secondary upward flow by adjusting the width of the non-static field area according to the width of the cast steel.
[75]
Herein, an example in which the first core 212 and the second core 222 , the third core 232 and the fourth core 242 are spaced apart in the width direction of the mold 100 will be described, and the mold ( 100), an example of forming a static field unapplied region and a static magnetic field applied region in the width direction has been described. However, in the width direction of the mold 100 , a static field non-applied area and a static magnetic field applied area may be formed.
[76]
4 is a cross-sectional view of a casting facility according to a modified example of the present invention. In the casting facility according to a modified example of the present invention, the first static magnetic field generator 210 and the second static magnetic field generator 220 are connected by a first connecting core 272 , and the third static magnetic field generator 230 and the fourth static magnetic field generator 230 are connected to each other. Except for connecting the static magnetic field generator 240 to each other with the second connection core 274, it may be formed to have substantially the same structure as the casting equipment of the above-described embodiment.
[77]
The first connecting core 272 connects the first core 212 of the first static magnetic field generator 210 and the second core 222 of the second static magnetic field generator 220 to each other along the width direction of the mold 100 . can connect At this time, the first connection core 272 may connect the other side of the first core 212 and the other side of the second core 222 to each other, and the outer surface of the first long side plate 111 constituting the mold 100 and It may be arranged to be spaced apart. The second connection core 274 connects the third core 232 of the third static magnetic field generator 230 and the fourth core 242 of the fourth static magnetic field generator 240 to each other along the width direction of the mold 100 . can connect At this time, the second connecting core 274 may connect the other side of the third core 232 and the other side of the fourth core 242 to each other, and the second long side plate 113 constituting the mold 100 may It may be arranged to be spaced apart.
[78]
In this way, the first core 212 and the second core 222 are connected with the first connecting core 272 , and the third core 232 and the fourth core 242 are connected with the second connecting core 274 . and supplying a direct current to the first static magnetic field generator 210, the second static magnetic field generator 220, the third static magnetic field generator 230, and the fourth static magnetic field generator 240, the first static magnetic field generator ( 210), the second static magnetic field generator 220, the third static magnetic field generator 230, and the fourth static magnetic field generator 240 may each form a static magnetic field. In this case, a static field may be formed from the outside of the mold 100 along the width direction of the mold 100 , and a static field may be formed along the thickness direction of the mold 100 . For example, an S pole may be formed on one side of the first core 212 and the third core 232 , and an N pole may be formed on one side of the second core 222 and one side of the fourth core 242 . In this case, the static magnetic field formed by each of the static magnetic field generators 210 , 220 , 230 , and 240 has a magnetic field direction from the S pole to the N pole along each of the cores 212 , 222 , 232 , and 242 . At this time, the magnetic field around each of the cores 212, 222, 232, 242 also has a magnetic field direction from the S pole to the N pole. A magnetic field may be formed in the thickness direction of the mold 100 by the direction. In the thickness direction of the mold 100 , the magnetic field is directed from the fourth magnetic field generator 240 to the first magnetic field generator 210 , and the second magnetic field generator 220 to the third magnetic field generator 230 is directed toward the can be formed. In addition, the magnetic field is applied to each of the cores 212, 222, 232, 242), the magnetic field strength gradually decreases. Accordingly, a magnetic field is canceled between the first static magnetic field generator 210 and the fourth static magnetic field generator 240 facing each other, so that a section in which no magnetic field is applied or a very weak magnetic field strength may be formed. This is because one side of the first core 212 and one side of the fourth core 242 facing each other have opposite polarities.
[79]
In addition, even between the second static magnetic field generator 220 and the third static magnetic field generator 230 facing each other, a section in which no magnetic field is applied or the magnetic field strength is very weak may be formed. This is because one side of the second core 222 and one side of the third core 232 facing each other have opposite polarities. Also, no magnetic field is applied or a magnetic field is applied between the first static magnetic field generator 210 and the second static magnetic field generator 220 and between the third static magnetic field generator 230 and the fourth static magnetic field generator 240 adjacent to each other. A section in which the intensity is very weak may be formed. Accordingly, between the static fields generated by the first static magnetic field generator 210 , the second static magnetic field generator 220 , the third static magnetic field generator 230 , and the fourth static magnetic field generator 240 , for example, the mold 100 is formed. A section in which no magnetic field is applied to the center in the thickness direction and the center in the width direction of the mold 100 in the thickness direction or in which the magnetic field strength is very weak, that is, a region in which a static magnetic field is not applied may be formed.
[80]
In addition, in the first connection core 272 connecting the first core 212 and the second core 222 , a static magnetic field having a magnetic field direction from the first static magnetic field generator 210 to the second static magnetic field generator 220 is provided. can be formed, and a static magnetic field having a magnetic field direction from the third static magnetism generator 230 to the fourth static magnetism generator 240 may be formed in the second connection core 274 . In this case, the magnetic field directions of the static fields formed in the first connection core 272 and the second connection core 274 may be formed to have opposite directions.
[81]
Accordingly, the magnetic field direction of the static field may be formed to rotate along the width direction and the thickness direction of the mold 100 . Accordingly, a region having a very weak magnetic field strength or no magnetic field in the width direction of the mold 100 may be formed between the static fields formed on both sides in the width direction of the mold 100 . Also, a region having a very weak magnetic field strength or no magnetic field may be formed between the magnetic fields formed on both sides in the thickness direction of the mold 100 along the thickness direction of the mold 100 . Accordingly, the region where the magnetic field formed along the thickness direction of the mold 100 and the region in contact with the magnetic field along the width direction intersect each other, for example, a region where the magnetic field strength is very weak or there is no magnetic field at the center of the mold 100 . , that is, a static magnetic field unapplied region may be formed.
[82]
[83]
5 is a view showing a state of controlling the flow of the melt by the casting method according to an embodiment of the present invention.
[84]
Figure 5 (a) is a view showing the flow state of the melt in the mold 100 before controlling the flow of the downward flow and the secondary upward flow using the static magnetic field generator 200, Figure 5 ( b) is a view showing the flow state of the melt when a static magnetic field is applied along the entire width direction of the mold 100, and FIG. It is a diagram showing the flow state of the melt when a static magnetic field applied region and a static magnetic field unapplied region are formed along the width direction.
[85]
The discharge flow of the melt M discharged through the discharge port 134 of the nozzle 130 collides with both inner surfaces of the mold 100 in the width direction of the mold 100 to form an upward flow and a downward flow. . In FIG. 5 , MF may mean mold flux, and MS may mean mold slag in which the mold flux is dissolved.
[86]
Referring to FIG. 5 (a), when the flow of the melt is not controlled using the static magnetic field generator 200, it can be seen that the movement distance of the inclusions, that is, the penetration depth, is very deep because the flow rate of the downflow is relatively fast. can In this case, it can be seen that the secondary upward flow is smoothly formed because the flow of the melt is not controlled using the static magnetic field generator 200 . However, the inclusions contained in the melt move far along the longitudinal direction of the mold 100, that is, in the drawing direction of the slab by the downward flow, and cannot sufficiently float upward by the secondary upward flow, so that a large amount of inclusions remain in the melt. indicates that
[87]
Referring to (b) of FIG. 5 , when a magnetic field is applied along the entire width direction of the mold 100, the flow velocity of the downflow is reduced by the magnetic field, and thus it can be seen that the moving distance of the inclusions downward is shortened. In addition, the formation of the secondary upward flow is suppressed by the magnetic field and the secondary upward flow is not properly formed, so the inclusions that have moved in the longitudinal direction of the mold 100, that is, in the drawing direction of the cast steel by the downward flow, are not floated upward. It can be seen that it remains as it is in the melt.
[88]
On the other hand, referring to FIG. 5C , when the flow of the melt is controlled using the static magnetic field generator 200, the flow velocity of the downflow is It can be seen that the reduced movement distance of the inclusions to the lower side is shortened. In addition, it can be seen that a static field unapplied area is formed in the center in the width direction of the mold 100, which is a non-static field unapplied area, so that the secondary upward flow is sufficiently formed, so that inclusions contained in the melt are smoothly floated upward and removed. there is.
[89]
6 is a view showing the flow analysis results of the secondary upward flow in the mold according to whether or not a static magnetic field is not applied in the width direction of the mold. Fig. 6 (a) is a view showing the flow state of the melt when a static magnetic field is applied over the entire width direction of the mold, and Fig. 6 (b) is a view showing a non-static field region in the center in the width direction of the mold. It is a diagram showing the flow state of the melt.
[90]
Referring to (a) of FIG. 6 , it can be seen that when a static field is applied over the entire width direction of the mold, the secondary upward flow is hardly formed. On the other hand, referring to FIG. 6 (b), when the non-static field is formed at the center in the width direction of the mold, the secondary upward flow is smoothly formed at the center in the width direction of the mold to which the static field is not applied. can be checked
[91]
As described above, by selectively forming a static magnetic field applied region and a static magnetic field unapplied region along the width direction of the mold, the flow of the melt can be locally controlled to secure the cleanliness of the melt. In addition, it is possible to improve the quality of the cast slab using such a melt.
[92]
On the other hand, in the casting facility according to an embodiment of the present invention, a moving magnetic field provided above the static magnetic field generator 200 from the outside of the mold 100 to control the flow of the melt in the upper part of the static magnetic field generator 200 . The generator 300 may be included. In this case, the controller 400 may control the operation of the moving magnetic field generator 300 to adjust at least one of the intensity and direction of the moving magnetic field.
[93]
A portion of the melt discharged from the nozzle 130 may form an upward flow after colliding with the short-side plate 120 . And, the moving direction of the upward flow is changed in the vicinity of the hot water surface of the melt to horizontally move toward the center in the width direction of the mold 100 . In this way, the flow of the melt moving toward the central side of the width direction of the mold 100, for example, the flow in the horizontal direction collides with the flow of the melt moving from the nozzle 130 and the opposite direction to form a vortex in the vicinity of the nozzle 130. there is. At this time, when the flow rate of the horizontal flow is too fast, there is a problem in that heterogeneous materials such as mold flux or mold slag on the top of the melt are mixed into the melt. On the other hand, when the flow rate of the horizontal flow is too slow, the temperature of the melt in the mold 100 may become non-uniform. Therefore, by controlling the horizontal flow of the melt in the vicinity of the hot water surface of the melt using the moving magnetic field generator 300, it suppresses mixing of heterogeneous materials such as mold flux or mold slag into the melt, and the melt in the mold 100 The temperature can be controlled uniformly. The flow speed of the horizontal flow of the melt is affected by the flow speed of the melt discharged to the discharge port 134 of the nozzle 130 , that is, the flow speed of the discharge flow. Therefore, by controlling the flow velocity of the discharge flow using the moving magnetic field generator 300 , it is possible to control the flow velocity of the horizontal flow of the melt formed near the molten water surface.
[94]
FIG. 7 is a cross-sectional view of the casting equipment taken along line BB′ shown in FIG. 1 .
[95]
The moving magnetic field generating unit 300 is provided on the upper portion of the static magnetic field generating unit 200 , for example, between the hot water surface of the melt and the lower end of the nozzle 130 , and directs the flow of the melt in different directions from the static magnetic field generating unit 200 . can be controlled Referring to FIG. 7 , the moving magnetic field generator 300 includes a plurality of moving magnetic field generators 310 , 320 , 330 and 340 provided to be spaced apart from each other in the width direction of at least the long side plate, and an alternating current to the plurality of moving magnetic field generators. A second current supply 350 that can be selectively supplied may be included. The plurality of moving magnetic field generators 310 , 320 , 330 , 340 includes a first moving magnetic field generator 310 provided on an upper portion of the first static magnetic field generator 210 in parallel with the first static magnetic field generator 210 ; The first moving magnetic field generator 310 and the nozzle 130 are disposed to be spaced apart from the first moving magnetic field generator 310 so that the nozzle 130 is disposed between the first moving magnetic field generator 310 and parallel to the second static magnetic field generator 220 on the upper part of the second static magnetic field generator The provided second moving magnetic field generator 320 and the second moving magnetic field generator 320 are disposed to face each other, and the second static magnetic field generator 230 is provided on an upper portion of the third static magnetic field generator 230 in parallel with the second moving magnetic field generator 230 The third moving magnetic field generator 330 and the third moving magnetic field generator 330 are disposed to be spaced apart from the third moving magnetic field generator 330 so that the nozzle 130 is disposed between the third moving magnetic field generator 330 and the fourth static magnetic field generator 240 . A fourth moving magnetic field generator 340 provided in parallel with the fourth static magnetic field generator 240 may be included on the upper portion. That is, the first moving magnetic field generator 310 and the second moving magnetic field generator 320 are provided outside the first long side plate 111 , and in the width direction of the mold 100 , a moving magnetic field applied region and a moving magnetic field non-applied region are provided. can form. In addition, The third moving magnetic field generator 330 and the fourth moving magnetic field generator 340 are provided on the outside of the second long side plate 113 to form a moving magnetic field applied area and a moving magnetic field non-applied area in the width direction of the mold 100 . can do. Each of the first moving magnetic field generator 310 , the second moving magnetic field generator 320 , the third moving magnetic field generator 330 , and the fourth moving magnetic field generator 340 includes a plurality of cores and a coil wound on the outside of the core. may include Each moving magnetic field generator 310, 320, 330, 340 may include three, four, five or more cores, wherein each moving magnetic field generator 310, 320, 330, 340 is An example including four cores will be described.
[96]
For example, the first moving magnetic field generator 310 extends in the thickness direction of the mold 100 , and the first core 312a , the second core 312b , and 3 are arranged in parallel with each other along the width direction of the mold 100 . No. core 312c and No. 4 core 312d, and No. 1 coil 314a, No. 2 coil 314b, and No. 3 coil 314c wound on the outside of each of the cores 312a, 312b, 312c, and 312d. ) and a fourth coil 314d. And the second current supply 350 is electrically connected to the first coil 314a, the second coil 314b, the third coil 314c, and the fourth coil 314d, each of the coils 314a, 314b, An alternating current may be selectively supplied to 314c and 314d). In this case, the second current supply 350, as shown in Table 1 below, each coil (314a, 314b, 314c, 314d) at the phase difference of 0 °, 90 °, 180 ° and 270 ° degrees S pole and A cosine current may be applied to each of the coils 314a, 314b, 314c, and 314d to have an N pole.
[97]
[Table 1]
1 coil 2 coil 3 coil 4 coil
0° S - N -
90° - S - N
180° N - S -
270° - N - S
[98]
Referring to Table 1, when AC power having a phase of 0° is supplied to the No. 1 coil 314a and the No. 3 coil 314c, the No. 1 coil 314a has an S pole, and the No. 3 coil 314c has an S pole. It can have an N pole. And when AC power having a phase of 90° is supplied to the second coil 314b and the fourth coil 314d, the second coil 314b has an S pole and the fourth coil 314d has an N pole. there is. When AC power having a phase of 180° is supplied to the No. 1 coil 314b and the No. 3 coil 314d, the No. 1 coil 314b may have an N pole and the No. 3 coil 314d may have an S pole. . In addition, when AC power having a phase of 270° is supplied to the second coil 314b and the fourth coil 314d, the second coil 314b has an N pole and the fourth coil 314d has an S pole. can When AC power is supplied to each coil in this way, the polarity of each coil is periodically changed according to the phase of the supplied AC current. Accordingly, in the first moving magnetic field generator 310 , the magnetic field moves in the direction in which the coils are arranged, that is, in the width direction of the mold 100 , that is, a moving magnetic field may be formed.
[99]
The second moving magnetic field generator 320 , the third moving magnetic field generator 330 , and the fourth moving magnetic field generator 340 may form a moving magnetic field in the same manner as the first moving magnetic field generator 310 . Accordingly, a moving magnetic field applied region and a moving magnetic field unapplied region may be formed along the width direction of the mold 100 . 7, 322a to 322d and 324a to 324d refer to the core and coil of the second moving magnetic field generator 320, and 332a to 332d and 334a to 334d refer to the core and coil of the third moving magnetic field generator 330, , 342a to 342d and 344a to 344d refer to the core and coil of the fourth moving magnetic field generator 340 .
[100]
The second current supply 350 includes a first moving magnetic field generator 310 , a second moving magnetic field generator 320 , a third moving magnetic field generator 330 and a fourth so that the magnetic field is formed in the width direction of the mold 100 . An alternating current may be supplied to the moving magnetic field generator 340 . In this case, the second current supply 350 may control the horizontal flow formed by the upward flow by controlling the flow velocity of the discharge flow in the mold 100 . To this end, the second current supply 350 includes the first moving magnetic field generator 310 and the second moving magnetic field generator so that the magnetic field direction is formed along a horizontal direction similar to the moving direction of the discharge flow, that is, along the width direction of the mold 100 . An alternating current may be supplied to 320 , the third moving magnetic field generator 330 , and the fourth moving magnetic field generator 340 . In this case, the second current supply 350 may supply an alternating current so that at least a portion of each of the moving magnetic field generators 310 , 320 , 330 , and 340 forms moving magnetic fields in different directions. For example, in the second current supply 350 , the first moving magnetic field generator 310 and the second moving magnetic field generator 320 provided on the outside of the first long side plate 111 have a moving magnetic field in the same direction, for example, a third direction. An alternating current is supplied to the third moving magnetic field generator 330 and the fourth moving magnetic field generator 340 provided on the outside of the second long side plate 113 to form a moving magnetic field in the same direction, for example, the fourth direction. can In this case, the third direction and the fourth direction may be opposite to each other. Alternatively, in the second current supply 350, a moving magnetic field in the same direction, for example, a third direction, is formed in the first moving magnetic field generator 310 and the fourth moving magnetic field generator 340 provided to face each other, An alternating current may be supplied so that a moving magnetic field in the same direction, for example, a fourth direction, is formed in the second moving magnetic field generator 320 and the third moving magnetic field generator 330 provided to face each other. At this time, the direction of the magnetic field formed by the first moving magnetic field generator 310 , the second moving magnetic field generator 320 , the third moving magnetic field generator 330 , and the fourth moving magnetic field generator 340 is the outlet of the nozzle 130 . It may be changed according to the flow rate of the discharge flow discharged in (134).
[101]
8 is a view showing an example of controlling the flow of a melt using a moving magnetic field generator. As shown in (a) of FIG. 8 , when the flow velocity of the discharge flow is excessively high, the flow velocity of the horizontal flow increases in the vicinity of the molten water surface. In this case, the second current supply 350 includes a first moving magnetic field generator 310 , a second moving magnetic field generator 320 , and a third moving magnetic field generator 330 such that a moving magnetic field is formed in a direction opposite to the moving direction of the discharge flow. ) and the fourth moving magnetic field generator 340 may be supplied with an alternating current. At this time, the second current supply 350 includes a first moving magnetic field generator 310, a second moving magnetic field generator 320, and a third moving magnetic field generator so that the direction of the moving magnetic field is formed from the edge of the mold 100 toward the center. 330) and the fourth moving magnetic field generator 340 may be supplied with an alternating current. Accordingly, the flow velocity of the discharge flow formed by being discharged from the discharge port 134 of the nozzle 130 is reduced, so that the molten water surface can be controlled stably.
[102]
On the other hand, when the flow velocity of the discharge flow is too slow as shown in FIG. In this case, the second current supply 350 includes the first moving magnetic field generator 310 , the second moving magnetic field generator 320 , and the third moving magnetic field generator 330 so that a moving magnetic field is formed in the same direction as the moving direction of the discharge flow. ) and the fourth moving magnetic field generator 340 may be supplied with an alternating current. At this time, the second current supply 350 includes a first moving magnetic field generator 310, a second moving magnetic field generator 320, and a third moving magnetic field generator so that the direction of the moving magnetic field is formed from the center to the edge of the mold 100. 330) and the fourth moving magnetic field generator 340 may be supplied with an alternating current. Accordingly, the flow rate of the discharge flow formed by being discharged from the discharge port 134 of the nozzle 130 is accelerated to smoothly form a flow such as a downward flow, an upward flow, and a secondary upward flow, thereby lowering the temperature of the melt in the mold 100 . can be controlled uniformly.
[103]
Meanwhile, the second current supply 350 includes a first moving magnetic field generator 310 , a second moving magnetic field generator 320 , and a third moving magnetic field generator to form a moving magnetic field rotating in the circumferential direction of the mold 100 . An alternating current may be supplied to the 330 and the fourth moving magnetic field generator 340 . If a moving magnetic field rotating along the circumferential direction of the mold 100 is formed in this way, when the temperature of the melt is not uniform or low near the molten water surface, the temperature of the melt can be uniformly controlled in the vicinity of the melt by stirring the melt. there is. Here, it has been described that the discharge flow and the horizontal flow of the melt are controlled by controlling the direction of the magnetic field, that is, the direction of the moving magnetic field. can be controlled In this case, the magnetic field strength may be changed by adjusting the current amount of the alternating current supplied to each of the moving magnetic field generators 310 , 320 , 330 , and 340 .
[104]
In this way, by controlling the discharge flow and the horizontal flow of the melt in the mold 100 using the moving magnetic field generator 300 in this way, the melt surface is stabilized, such as mold slag or mold flux disposed on the melt surface. Incorporation of the same heterogeneous material into the melt can be suppressed or prevented.
[105]
[106]
Although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and common knowledge in the field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims Those having the above will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the technical protection scope of the present invention should be defined by the following claims.
Industrial Applicability
[107]
According to the present invention, by selectively applying a static magnetic field in the width direction of the mold to selectively control the flow of the melt in the longitudinal direction of the mold, mixing of different materials such as mold flux or mold slag into the melt is suppressed and high quality product can be manufactured. can do. Through this, the cleanliness of the melt can be secured and the quality of the product manufactured using the melt can be improved.
Claims
[Claim 1]
A casting equipment for casting a slab, comprising: a mold providing a space for accommodating a molten material therein; a nozzle provided on the mold to supply the melt to the mold; a static magnetic field generator provided outside the mold in the width direction to control directions of magnetic fields in different directions at both edge portions in the width direction of the mold; and a control unit capable of controlling the operation of the static magnetic field generator.
[Claim 2]
The method according to claim 1, wherein the mold comprises a pair of long-side plates provided to be spaced apart and a pair of short-side plates connecting both sides of the pair of long-side plates, respectively, wherein the static magnetic field generator comprises: a width of the mold a plurality of static magnetic field generators provided in the width direction of the long side plate under the nozzle so as to be spaced apart from the center in the direction; and a first current supply capable of supplying a direct current to the plurality of static magnetic field generators so as to form a magnetic field passing in the thickness direction of the mold from both sides of the nozzle in the width direction of the mold.
[Claim 3]
3. The method according to claim 2, wherein each of the plurality of static magnetic field generators comprises: a core extending along a portion of a width direction of the long side plate and disposed to be spaced apart from each other; and a coil wound on the outside of the core.
[Claim 4]
The method according to claim 3, wherein the plurality of static magnetic field generators include: a first static magnetic field generator; a second static magnetic field generator disposed to be spaced apart from one side of the first static magnetic field generator such that the nozzle is disposed between the first static magnetic field generator; a third static magnetic field generator disposed to face the second static magnetic field generator; and a fourth static magnetic field generator disposed to be spaced apart from one side of the third static magnetic field generator such that the nozzle is disposed between the third static magnetic field generator and disposed to face the first static magnetic field generator, and , the first current supplier forms opposite polarities in a direction opposite to each other in the thickness direction of the mold, and forms opposite polarities in a width direction of the mold, the first static magnetic field generator and the second static electricity supply A casting facility capable of supplying a direct current to a field generator, the third static magnetic field generator, and the fourth static magnetic field generator.
[Claim 5]
5. The method of claim 4, wherein the first static magnetic field generator and the second static magnetic field generator are spaced apart by a first distance, the third static magnetic field generator and the fourth static magnetic field generator are spaced apart by a second distance, and the first static magnetic field generator is spaced apart from each other by a second distance. The distance and the second distance are the same size of the foundry.
[Claim 6]
The method according to claim 5, When the total width of the slab is 100, the first distance and the second distance is 4 to 36 casting equipment.
[Claim 7]
The casting according to claim 6, wherein at least one of the first static magnetic field generator, the second static magnetic field generator, the third static magnetic field generator, and the fourth static magnetic field generator is movable along the width direction of the mold. equipment.
[Claim 8]
The apparatus of claim 7 , further comprising: a first connecting core for connecting the first static magnetic field generator and the second static magnetic field generator; and a second connecting core for connecting the third static magnetic field generator and the fourth static magnetic field generator.
[Claim 9]
The casting facility according to claim 8, wherein the static magnetic field generator is capable of generating a magnetic field rotating in a circumferential direction of the mold.
[Claim 10]
10. The method according to any one of claims 1 to 9, further comprising a moving magnetic field generator provided above the static magnetic field generator and capable of generating a moving magnetic field to control the flow of the melt, wherein the control unit includes the strength of the moving magnetic field. and a casting facility capable of controlling the operation of the moving magnetic field generator to adjust at least one of the directions.
[Claim 11]
The casting facility according to claim 10, wherein the moving magnetic field generator includes a plurality of moving magnetic field generators capable of forming a moving magnetic field in the width direction of the mold at both sides of the nozzle.
[Claim 12]
The casting facility according to claim 11 , wherein the moving magnetic field generator is arranged in parallel with the static magnetic field generator, and the flow of the melt can be controlled in different directions from the static magnetic field generator.
[Claim 13]
The process of injecting the melt into the mold using a nozzle; controlling the flow of the melt in the longitudinal direction of the mold by forming a static field applied region and a static magnetic field unapplied region in the width direction of the mold; And the process of drawing the slab; casting method comprising a.
[Claim 14]
The method according to claim 13, wherein before the process of injecting the melt, comprising the process of arranging the nozzle in the center in the width direction of the mold, and the process of controlling the flow of the melt is located in the center in the width direction of the mold A casting method comprising the steps of forming a static magnetic field unapplied area, and forming the static magnetic field applied area on both sides of the static magnetic field unapplied area.
[Claim 15]
The casting method of claim 14 , wherein the controlling of the flow of the melt includes forming the static magnetic field applied region and the static magnetic field unapplied region below the nozzle.
[Claim 16]
The method according to claim 15, wherein the controlling of the flow of the melt comprises forming a static magnetic field along a thickness direction of the mold, and the forming of the static magnetic field applying region includes forming the static magnetic field in the width direction of the mold. A casting method comprising the step of forming a static magnetic field so that the magnetic field directions are formed in opposite directions on both sides of the .
[Claim 17]
The casting method of claim 16 , wherein the controlling of the flow of the melt includes forming the static magnetic field unapplied region in a portion of a central portion in the width direction of the mold in which the nozzle is disposed.
[Claim 18]
The casting method of claim 17 , wherein the controlling of the flow of the melt includes controlling the range of the static magnetic field applied region so that the static magnetic field unapplied region has a magnetic field of 0 to 100 Gauss.
[Claim 19]
The casting method according to claim 18, wherein the controlling of the flow of the melt comprises adjusting the distance between the static field application regions according to the width of the cast slab.
[Claim 20]
The method according to claim 19, wherein the controlling of the flow of the melt comprises forming the static field application regions on both edges in the width direction of the mold to reduce the flow velocity of the downflow of the melt, and between the static field application regions. and forming an upward flow of the molten material by forming the static magnetic field unapplied region in the molten metal.
[Claim 21]
The method of claim 20, wherein the controlling of the flow of the melt further comprises a process of controlling the flow of the melt in the width direction of the mold by forming a moving magnetic field applied region and a moving magnetic field non-applied region in the width direction of the mold. A casting method comprising.
[Claim 22]
The casting method according to claim 21, wherein the controlling of the flow of the melt in the width direction of the mold comprises forming a moving magnetic field applied region and a moving magnetic field non-applied region between the molten water surface and the lower end of the nozzle. .
[Claim 23]
The casting method according to claim 22, wherein the forming of the moving magnetic field application region includes forming a moving magnetic field in the width direction of the mold at both sides of the nozzle in the width direction of the mold.
[Claim 24]
The casting method of claim 23 , wherein the forming of the moving magnetic field application region includes adjusting at least one of a magnetic field strength and a direction of the moving magnetic field.