JPS645985B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a horizontal continuous casting apparatus.

In conventional horizontal continuous casting equipment, the tundish nozzle made of refractory material and the water-cooled mold are fixed to each other in order to prevent molten metal from flowing out between the tundish nozzle and the water-cooled mold. It was configured. Therefore, the portion of the tundish nozzle adjacent to the water-cooled mold is cooled, and a solidified shell is formed at the molten metal contact area, which is fixed to the tundish nozzle. Furthermore, since the molten metal enters the pores of the refractory material constituting the tundish nozzle and solidifies as it is, the adhesion force increases. Therefore, when the cast body is pulled out, the solidified shell sometimes ruptures and a so-called breakout occurs.

In the prior art to solve this problem, a non-porous silicon nitride ring or boron nitride ring with excellent lubricity is hermetically connected between the tundish nozzle and the mold. These silicon nitride rings and boron nitride rings have a short lifespan and are expensive.
Moreover, even if these materials are used, although they have the effect of alleviating the sticking of the tundish nozzle and the coagulating shell, it is not possible to completely avoid the sticking of the mold tube and the coagulating shell.
As seen in 15332, intermittent extraction is forced.

In order to solve these drawbacks of the prior art, an electromagnetic field generating means that generates a higher magnetic flux density at the bottom than at the top of the molten metal is placed near the boundary between the tundish nozzle and the mold. A horizontal continuous casting facility has been proposed in which the casting is constricted near the boundary (Japanese Patent Application No. 56-94333). By squeezing the molten metal in this way, the molten metal does not come into contact with the tundish nozzle, preventing the solidified shell from sticking to the tundish nozzle as described above, and preventing continuous drawing. It becomes possible.
Furthermore, since it is not necessary to fix the tundish nozzle and the mold, it is possible to vibrate the mold, which also prevents the coagulation shell from sticking to the tundish nozzle or the mold.

However, since the amount of molten metal stored in the tundish changes, the static pressure acting on the surface layer of the molten metal in the tundish nozzle and the mold also changes. In particular, during unsteady conditions such as at the end of casting or when replacing the ladle, the liquid level of the molten metal in the tundish changes greatly, and the static pressure of the molten metal in the tundish nozzle and mold changes accordingly. In such a case, the position where the molten metal squeezed by the electromagnetic field generating means comes into contact with the inner surface of the mold moves in response to fluctuations in static pressure. As the position of contact of the molten metal with the inner surface of the mold changes, the total length of the cooling zone within the mold changes. Since the solidified thickness changes accordingly, it becomes impossible to obtain a good slab. Furthermore, in the mold, the static pressure is greater at the lower part of the molten metal, so even with the electromagnetic field generating means, the contact pressure of the molten metal against the inner surface of the mold tends to be greater at the lower part. Therefore, the cooling effect of the lower part of the molten metal becomes large and uneven cooling makes it impossible to obtain a good slab. This means that
The same is true in the prior art, as shown in Japanese Utility Model Application No. 52-160615, in which an electromagnetic force is generated to apply a restriction to the molten metal from a tundish nozzle toward the center.

Another prior art is JP-A-53-76130. In this prior art, in order to perform gravity compensation of the molten metal, an electrode is immersed in the molten metal in a tundish nozzle, and a longitudinal current is passed through the molten metal.
It is configured to compensate for the gravity of the slab by generating a magnetic field perpendicular and horizontal to the longitudinal direction of the slab. In such prior art, the electrodes are immersed in the molten metal and a current is supplied to the molten metal, so maintenance thereof is troublesome.

An object of the present invention is to provide a horizontal continuous casting apparatus in which the thickness of the solidified shell produced on the surface layer of molten metal cooled on the inner surface of the mold is uniform along the circumferential direction.

The first invention of the present invention is constructed by surrounding at least a portion of the tundish nozzle near the mold, and winding the tundish nozzle at intervals in the radial direction, and having an axis above the axis of the tundish nozzle and the mold. A coil that is provided eccentrically so as to have a coil, is excited by AC power, and applies electromagnetic force toward the center of the molten metal so that the diameter of the molten metal is reduced near the boundary between the tundish nozzle and the mold. a detection means for detecting the contact start positions of the reduced diameter molten metal on the inner surface of the mold in the upper and lower directions; a drive means for moving the coil up and down; and a contact start position in response to the detection output of the detection means. and control means for controlling the driving means so as to displace the coil upward when the coil is located at the upper part of the molten metal and is downstream in the drawing direction than the lower part.

In addition, the second invention of the present invention is constructed by surrounding at least a portion of the tundish nozzle near the mold and winding the tundish nozzle at intervals in the radial direction, and the axis of the tundish nozzle is above the axis of the tundish nozzle. The molten metal is provided eccentrically so as to have a tundish nozzle, and is excited by alternating current power to apply an electromagnetic force to the molten metal toward the center so that the diameter of the molten metal decreases near the boundary between the tundish nozzle and the mold. a coil; a detection means for detecting the thickness of the solidified shell above and below the cast body at the mold exit; a driving means for moving the coil up and down; and a thickness of the solidified shell in response to a detection output of the detection means. control means for controlling the driving means to displace the coil upward when the coil is larger at the lower part than at the upper part.

According to the first invention, the coil is provided so as to be movable up and down so as to reduce the diameter of the molten metal near the boundary between the tundish nozzle and the mold. The detection means detects the upper and lower contact start positions of the reduced diameter molten metal with the inner surface of the mold. Therefore, the contact start position is at the upper part and downstream of the lower part in the pulling direction (backward in the pulling direction 45, that is, at the second
5 and 7), the coil is displaced upward. As a result, a larger electromagnetic force acts on the lower part of the molten metal toward the center. Therefore, the contact start position where the molten metal contacts the inner surface of the mold can be adjusted to be approximately the same vertically, or so that the lower part of the molten metal is on the downstream side in the drawing direction than the upper part. By this,
The thickness of the solidified shell of the casting at the mold exit can be made approximately equal between the upper and lower parts.

Further, according to the second invention, the thickness of the solidified shell above and below the cast body at the mold exit is detected,
When the thickness of the solidification shell is greater at the bottom than at the top, the coil can be displaced upward, thereby exerting a larger electromagnetic force on the bottom of the molten metal toward the center, and the thickness of the solidification shell can be made approximately equal at the top and bottom of the cast body.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall system diagram showing the basic configuration of the present invention. In this horizontal continuous casting equipment, the tundish 1 is
A heating device 2 is provided to stabilize the temperature of the molten metal within. Cast body 4 from mold 3
is pulled out from the cooling zone 5 by a drawing device 6 and cut by a cutting device 7 to obtain an ingot 9. This ingot 9 is conveyed by a roller table 10.

FIG. 2 is an enlarged sectional view of the vicinity of the mold 3.
The tundish 1 is lined with a refractory material 11 and stores molten metal 12. A tundish nozzle 14 made of a refractory material is fixed to the tundish 1 by a mounting hardware 13. The mold 3 has a coolant passage 15 in which a copper mold tube 33 is cooled, and a passage 16 for the cast body 4 of the mold 3 communicates coaxially with the tundish nozzle 14 . This mold 3 is fixed to a tundish nozzle 14. Near the boundary 17 between the tundish nozzle 14 and the mold 3, an electromagnetic field generating means 18 is provided which is made of a coil surrounding the boundary 17 and is energized by AC power from a power source 19. Due to the electromagnetic field of this electromagnetic field generating means 18,
The molten metal 12 flowing near the boundary 17 is reduced in diameter and narrowed inward in the radial direction. Therefore boundary 17
Nearby, the molten metal 12 is prevented from coming into contact with the portion of the tundish nozzle 14 near the mold 3. Therefore, the tandate nozzle 14
This prevents the solidified shell from adhering to the cast body 4, making it possible to continuously pull out the cast body 4.

The electromagnetic field generating means 18 includes a first coil 20 surrounding the tundish nozzle 14 and the vicinity of the boundary 17.
and a second coil 21 surrounding at least a portion of the tundish nozzle 14 closer to the mold. The coil wires of both of these coils 20 and 21 are wound around the tundish nozzle 14 and a portion of the mold 3 at intervals in the radial direction. When an excitation current is passed through each coil 20, 21, an electromagnetic force acts on the molten metal 12 toward its center, and the molten metal 12 is thereby constricted near the boundary 17. The first coil 20 is arranged so as to be substantially concentric with the tundish nozzle 14, and the second coil 21 is arranged eccentrically so that its center position is located above the axis of the tundish nozzle 14. The first coil 20 applies an almost uniform electromagnetic force toward the center of the molten metal 12 over the entire circumference of the tundish nozzle 14, and the second coil 21 applies an electromagnetic force that increases toward the bottom of the molten metal 12.
Act toward the center of the In the tundish nozzle 14, a static pressure that increases downwardly acts on the surface layer of the molten metal 12, so as mentioned above, the electromagnetic force that increases downwardly is applied by the second coil 21. By acting, molten metal 1
2 is narrowed so that the gap with the inner surface of the tundish nozzle 14 is substantially uniform along the circumferential direction. Note that when the excitation current decreases, an induced current opposite to that when the excitation current increases flows in the molten metal 12, and a negative squeezing force acts on the molten metal 12, so that the radial direction of the first coil 20 and the second coil 21 An induced current absorbing plate 18' is provided inside to absorb the reverse induced current.

A ring-shaped header 41 is formed in the tundish nozzle 14. A nozzle 42 is formed in this header 41 so as to face inward in the radial direction of the tundish nozzle 14 . A lubricant 46 is pumped into the header 41 via a conduit 43. The nozzle 42 is a tundish nozzle 1 in which the molten metal 12 is
It is located at a position further forward in the drawing direction 45 than a position 44 which is farther away from 4. The lubricant 46 is Cao, SiO ₂ ,
The main component is Al ₂ O ₃ powder, and powders with good electrical conductivity such as pure iron and Co are also mixed in. In the lubricant 46 mixed with powder having good electrical conductivity, an electromagnetic force directed inward in the radial direction of the tundish nozzle 14 and the mold 3 acts on the powder having good electrical conductivity. This ensures that the lubricant 46 adheres to the entire outer circumferential surface of the reduced diameter molten metal 12. Therefore, the lubricity with the portion where the diameter-reduced molten metal 12 first comes into contact with the casting passageway 16 is improved. The lubricant 46 may be made of rapeseed oil as a main component, with powder of pure iron, cobalt, etc. mixed therein.

In such horizontal continuous casting equipment, when the amount of molten metal 12 stored in the tundish 1 changes, the position 23 at which the reduced diameter portion 22 of the molten metal 12 starts contacting the inner surface of the mold tube 33 in the mold 3 changes. . Then, molten metal 1
The distance l at which the solidified shell 24 contacts the inner surface of the mold tube 33 changes, and the solidified thickness of the solidified shell 24 at the surface layer of the molten metal 12 changes, making it impossible to obtain a good slab.

Therefore, the electromagnetic force of the electromagnetic field generating means 18 is adjusted so that the contact start position 23 is maintained at a desired position. That is, the position detection means 25 is provided near the desired contact start position 23. As the position detection means 25, as shown in FIG. 3, a plurality of thermocouples 26 may be embedded in the mold tube 33 at intervals in the axial direction. The compensation conductors 27 of these thermocouples 26 are connected to the mold 3
It liquid-tightly penetrates the stopper 25a fixed to the outer wall 3a of the container and is pulled out. As the position detection means 25, in addition to the above-mentioned thermocouple 26, a temperature-sensitive magnetic material may be used, or the contact start position may be detected using gamma rays. Note that if the magnetic field force is large enough to affect detection of the contact position, the supply of power to the electromagnetic force generating coil may be stopped for a very short time at a position where the current value is 0, and detection may be performed during that time.

The contact start position of the molten metal 12 detected by the position detection means 25 is given to the control means 28, and the control means 28 receives a signal from the power supply 19 so that the contact start position 23 is at a preset substantially constant position. The power supplied to the second coil 21 is adjusted. That is, when the amount of molten metal 12 stored in the tundish 1 becomes relatively large and the static pressure acting on the molten metal 12 near the boundary 17 becomes large, the diameter of the reduced diameter portion 22 increases as shown by the imaginary line 29. becomes. Accordingly, the position at which the molten metal 12 starts contacting the inner surface of the mold tube 33 is located in front of the desired contact start position 23 along the drawing direction 45 of the molten metal 12 (i.e., on the upstream side in the drawing direction 45, at the second position).
(left side of the figure) position. Therefore, the control means 28
By increasing the power supplied from the power source 19, the second coil 2
Increase the electromagnetic force due to 1. As a result, the increased static pressure is compensated by the increased electromagnetic force, and the reduced diameter portion 22 returns to its original state as shown by the solid line in FIG.
The contact start position 23 is held at the desired position.
Further, when the amount of molten metal 12 stored in the tundish 1 becomes relatively small and the static pressure near the boundary 17 becomes small, the diameter of the reduced diameter portion 22 becomes smaller than the imaginary line 30 in FIG.
The contact start position becomes smaller as shown by , and the contact start position is located behind the desired contact start position 23 along the pull-out direction 45 (downstream side of the pull-out direction 45, right side in FIG. 2). Therefore, the control means 28
The electromagnetic force generated by the second coil 21 is reduced by reducing the power supplied from the second coil 21. As a result, the reduced diameter portion 22 returns to its original position, and the contact start position 23 is maintained at a desired position.

In this way, the contact start position 23 of the molten metal 12 with the inner surface of the mold tube 33 is maintained at a predetermined constant position, so that the solidified thickness of the solidified shell 24 is maintained at a substantially constant value, resulting in a good condition. This makes it possible to obtain slabs.

Note that since the diameter of the reduced diameter portion 22 is substantially constant, the position 44 where the molten metal 12 begins to separate from the inner surface of the tundish nozzle 14 is also maintained at a substantially constant position. Therefore, the nozzle 42 for supplying the lubricant 46 is not blocked by the molten metal 12, and the lubricant 46 can be stably supplied.

The above-described configuration is an example in which the power supplied from the power source 19 to the second coil 21 is controlled according to the contact start position of the molten metal 12. The electromagnetic force from the second coil 21 may be adjusted so that the contact start positions of the second coil 21 are detected and the contact start positions become the same set position along the axial direction. In that case, the second coil 21 is controlled to move up and down.

Next, an embodiment in which the second coil 21 is moved up and down will be described with reference to FIGS. 4, 5, and 6. In this embodiment, the second coil 2
1 is moved up and down by the driving means 31. Moreover, the amount of movement is such that the contact start position of the molten metal 12 detected by the position detection means 34 and 35 provided at the upper and lower parts of the mold tube 33 near the contact start position 23 is aligned with the axis of the mold tube 33. the control means 32 so as to be at substantially the same position along the
controlled by.

A pedestal 36 is fixedly provided below the boundary 17 between the tundish nozzle 14 and the mold 3. Supports 37 and 38 are provided on the pedestal 36 and extend upwardly on both sides of the tundish nozzle 14, and support stands 39 and 40 are provided at the upper ends of the supports 37 and 38, respectively. The first coil 20 is housed in a first storage box 47 having a rectangular cross section perpendicular to the axes of the tundish nozzle 14 and the mold 3, and the first storage box 47 is fixedly provided within the first cooling box 48. . In the first storage box 47, an inert gas is sealed or an insulating cooling liquid is circulated, and in the first cooling box 48, cooling water flows. The first storage box 47 and the first cooling box 48 are integrally fixed to the first support frame 49.
Support stands 39, 40 are provided on both sides of the first support frame 49.
Projections 50 and 51 are integrally provided above and project outward. Bolts 52 and 53 that extend downward and abut against the upper surfaces of the supports 39 and 40 are screwed into these protrusions 50 and 51, respectively.
Bolts 54 and 55 extending in the lateral direction and abutting on the sides of the protrusions 50 and 51 are screwed into the first support frame 49 by adjusting the amount of protrusion of each of the bolts 52 to 55, respectively. That is, the first coil 20
The vertical and lateral positions of are arbitrarily and fixedly adjusted.

The second coil 21 is connected to the tundish nozzle 14.
and the first coil 20, the second storage box 56 surrounds the tundish nozzle 14, has a rectangular cross section perpendicular to the axis, and is filled with an inert gas or circulated with an insulating coolant. Ru. The second storage box 56 is fixedly provided in a second cooling box 57 through which cooling water flows, and the second storage box 56 and the second cooling box 57 are integrally fixed to the second support frame 58. be done. Guide members 59 and 6 extending inward at both ends along the pulling direction 45 are provided on both sides of the first support frame 49.
0 are fixed respectively, and sliding pieces 6 that slide on the respective guide members 59 and 60 are provided on both sides of the second support frame 58.
1 and 62 are respectively fixed. By these guide members 59, 60 and sliding pieces 61, 62,
The second support frame 58 and the second coil 21 are guided in the vertical direction.

The driving means 31 includes first swing pieces 63 and 64, a connecting rod 65, a second swing piece 66, and a hydraulic cylinder 6.
7 and a hydraulic pressure supply means 68. The first swing pieces 63 and 64 are approximately L-shaped, and rollers 69 and 70 are rotatably supported at one end of the first swing pieces 63 and 64 so as to be rotatable around an axis along the drawing direction 45. 70 is brought into contact with the lower surface of the second support frame 58. The bent portions of each of the first swinging pieces 63 and 64 are supported by pivots 71 and 72 having axes parallel to the rotation axes of the rollers 69 and 70, and these pivots 71 and 72 are mounted on the pedestal 36. Legs 7 erected on
3,74.

The connecting rod 65 extends below the first support frame 49 along the pulling direction 45, and has shafts 75, 7 extending parallel to the pivot shafts 71, 72 at one end and in the middle thereof.
6 are connected. These shafts 75 and 76 are connected to the other ends of the first swing pieces 63 and 64. The second swing piece 66 is approximately L-shaped, and its bent portion is connected to the support column 38.
A pin 7 parallel to the pivot shafts 71 and 72 is placed in a fixed position.
It is supported by 7. The second swinging piece 66 has one end attached to the other end of the connecting rod 65 and a pin 7 parallel to the pin 77.
8.

The hydraulic cylinder 67 has an axis extending in the vertical direction and is supported by the column 38, and the tip of the piston rod 79 is connected to the other end of the second swing piece 66 via a pin 80 parallel to the pin 78. connected to.

In such a driving means 31, when the hydraulic cylinder 67 is driven to expand and contract, the second swinging piece 66 swings around the pin 77 as shown by the arrow 81, and the connecting rod 65 moves as shown by the arrow 82. As shown, the first rocking piece 6 is reciprocated in the axial direction.
3 and 64 swing around pivots 71 and 72 as shown by arrow 83. Therefore, the second support frame 58
The second coil 21 is moved up and down by rollers 69 and 70. Note that a spring 84 is interposed between the upper surface of the upper part of the second support frame 58 and the lower surface of the upper part of the first cooling box 48, and the second support frame 58 is moved downward by the spring force of the spring 84. is being energized towards.

As shown in FIG. 7, the position detecting means 34 and 35 are provided to detect the position at which the molten metal starts contacting the upper and lower inner surfaces of the mold tube 33 at the end near the tundish nozzle 14. These position detecting means 34, 35 are constructed by embedding a plurality of thermocouples 85, 86 in the mold tube 33 at intervals in the axial direction, similar to the position detecting means 25 in the configuration of FIGS. 1 to 3, for example. It consists of The contact start positions at the upper and lower parts of the molten metal 12 detected by the position detection means 34 and 35 are provided to the control means 32.

FIG. 8 is a block diagram showing the configuration of the control means 32. Signals from the position detection means 34 and 35 are applied to a comparator 88 via a calculation section 87 of the control means 32. A signal from a setter 89 is input to the comparator 88 , and the comparator 88 provides a signal corresponding to the difference between the signal voltages from the arithmetic unit 87 and the setter 89 to the control unit 90 . The control unit 90 is a comparator 88
The hydraulic pressure supply means 68 is controlled in response to a signal from the hydraulic pressure supply means 68. The control means 32 controls the second drive means 31 so that the contact start position of the molten metal 12 with the inner surface of the mold tube 33 is the same position along the axial direction at the upper and lower parts, and at a preset position. The vertical position of the coil 21 is controlled. That is, the contact start position is the position detection means 3.
When the upper part detected by 4 is on the downstream side in the drawing direction 45 (to the right in FIG. 7) than the lower part detected by another position detecting means 35, the second coil 21 moves upward. Displaced. Therefore, a large electromagnetic force in the center direction acts on the lower part of the molten metal 12, so that the contact start position is the same on the upper and lower sides as described above, or the upper part 167 is lower than the lower part 166 as shown in FIG. It is also arranged to be on the upstream side in the drawing direction 45 (to the left in FIG. 9).

As described above, when the contact start position of the molten metal 12 to the inner surface of the mold tube 33 is maintained at the same position set at the upper and lower parts, both sides of the molten metal 12 are also necessarily at the same position. Therefore, the molten metal 12 starts to come into contact with the inner surface of the mold tube 33 at the same set position along the axial direction over the entire circumference of the inner surface of the mold tube 33. Thereby, mold tube 33
Since the length of the cooling zone in the molten metal becomes uniform over the entire circumference of the molten metal and the solidification thickness becomes uniform over the entire circumference, a good slab can be obtained.

As another embodiment of the present invention, as shown in FIG. 7, solidification thickness gauges 91 and 92 may be provided at the outlet of the mold 3 to measure the thickness of the solidified shell in the upper and lower surface layer portions of the molten metal 12. The values detected by these solidification thickness gages 91 and 92 are provided to a comparator 88 via a calculation section 93 of the control means 32, as shown in FIG. In this way, the thickness of the solidified shell at the exit of the mold 3 is fed back to the control of the driving means 31,
More precise control becomes possible. Note that the solidification thickness gauges 91 and 92 may be replaced with radiation surface thermometers. That is, when the thickness of the solidified shell is greater at the bottom than at the top, the second coil 21 is displaced upward. Therefore, a large electromagnetic force in the center direction acts on the lower part of the molten metal 12, and the contact start position can be moved downstream in the drawing direction, or the contact pressure of the lower part of the molten metal 12 with the inner surface of the mold tube 33 can be reduced. Can be made smaller. In this way, the thickness of the solidified shell can be made equal in the upper and lower parts at the exit of the mold 3.

As yet another embodiment of the present invention, the first coil 20 may be omitted in the embodiments of FIGS. 4-8.

In another embodiment of the invention, the electromagnetic field generating means may be movable along the withdrawal direction 45. Thereby, the contact start position of the molten metal 12 can be changed, and the cooling conditions can be changed.

As a further embodiment of the present invention, as shown in FIG. 9 in a simplified manner, the contact start position 166 at the lower part of the mold tube 33 is controlled to a position further forward in the drawing direction 45 than the contact start position 167 at the upper part. You may also do so. In this way, the contact length of the molten metal 12 with the mold tube 33 is different in the upper and lower parts, and the contact length in the lower part is smaller, but the contact pressure with the mold tube 33 in the lower part of the molten metal 12 is greater. . Therefore, even if the contact length is relatively short, the cooling conditions are equal to the upper part,
Therefore, the solidified thickness can be made uniform over the entire circumference of the molten metal 12.

As another embodiment of the invention, each hydraulic cylinder 6
7 may be a pneumatic cylinder or a motor. Further, in each of the above-described embodiments, the tundish nozzle 14 and the mold 3 have a rectangular cross-section perpendicular to the axis, but the tundish nozzle 14 and the mold 3 may have a circular cross-section perpendicular to the axis. Tandate nozzle 14
The inner surfaces of the mold 3 and the mold 3 may be flush with each other,
It doesn't have to be flush.

As described above, according to the first invention, the coil is displaced up and down so that the contact start position of the molten metal with the mold is a preset position, so that gravity compensation of the molten metal can be reliably performed. As a result, cooling can always be achieved under stable cooling conditions regardless of fluctuations in the static pressure acting on the surface layer of the molten metal, and a good slab can be obtained. Further, since the position where the molten metal leaves the tundish nozzle is also held at a set position, the lubricant can be stably supplied.

Furthermore, according to the second invention, the thickness of the upper and lower solidified shells of the cast body at the mold exit can be made almost equal, thereby making the solidified thickness uniform over the entire circumference of the molten metal. I can do it.
In this way, cooling can always be achieved under stable cooling conditions, and good slabs can be obtained.

[Brief explanation of drawings]

FIG. 1 is an overall system diagram showing the basic structure of the present invention, FIG. 2 is an enlarged sectional view of the vicinity of the mold 3,
3 is an enlarged sectional view showing the vicinity of the position detection means 25, FIG. 4 is a sectional view of an embodiment of the present invention, FIG. 5 is a sectional view taken from the cutting plane line - in FIG.
The figure is a sectional view taken from the cutting plane line - in FIG. 4, FIG. 7 is an enlarged sectional view of the vicinity of the mold 3 in FIG. 4, FIG. 8 is a block diagram showing the configuration of the control means 32, and FIG. Figure 3 is a simplified cross-sectional view of another embodiment of the invention. 3...mold, 12...molten metal, 14...
Tandate nozzle, 17... Boundary, 18...
Electromagnetic field generating means, 19...Power supply, 20...First coil, 21...Second coil, 23...Contact start position, 24...Coagulation shell, 25, 34, 35...
Position detection means, 28, 32... Control means, 31...
...Driving means, 45...Drawing direction, 67...Hydraulic cylinder, 91, 92...Coagulation thickness gauge.

Claims (1)

[Scope of Claims] 1. The coil is wound around at least a portion of the tundish nozzle near the mold and is wound at intervals in the radial direction, and the axis is above the axis of the tundish nozzle and the mold. The molten metal is provided eccentrically so as to have a tundish nozzle, and is excited by alternating current power to apply an electromagnetic force to the molten metal toward the center so that the diameter of the molten metal decreases near the boundary between the tundish nozzle and the mold. a coil; a detection means for detecting the contact start positions of the reduced diameter molten metal on the inner surface of the mold; a drive means for moving the coil up and down; and a contact start position in response to a detection output of the detection means. 1. A horizontal continuous casting apparatus comprising: a control means for controlling the driving means to displace the coil upward when the coil is located at the upper part of the molten metal and downstream from the lower part in the drawing direction. 2. It is configured by surrounding at least the part of the tundish nozzle near the mold and is wound at intervals in the radial direction, and is eccentric so that it has an axis above the axes of the tundish nozzle and the mold. A coil is provided at the mold outlet and is excited by AC power to apply an electromagnetic force to the molten metal toward the center so that the molten metal contracts in diameter near the boundary between the tundish nozzle and the mold; a detection means for detecting the thickness of the solidified shell on the upper and lower sides of the cast body; a driving means for moving the coil up and down; and control means for controlling the drive means to displace the coil upward when the coil is large.