JP2004314097A - Mold for continuous casting, and continuous casting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cast a slab in which tapers are imparted to four faces, and thereby, inner defects are reduced, and capable of improving product quality and yield. <P>SOLUTION: The mold 14 for continuous casting is provided with four movable molds 20, 22, 24 and 26 arranged in a mutually orthogonal relation. The four movable molds 20, 22, 24 and 26 are abutted on the inner faces of another movable molds 20, 22, 24 and 26 orthogonally crossed with the one side face thereof, so that a casting space S is closely defined. The respective movable molds 20, 22, 24 and 26 are moved forwards and downwards parallel to the confronted movable molds 20, 22, 24 and 26 by a first fluid-pressure cylinder 36. The respective movable molds 20, 22, 24 and 26 are energized by the first fluid-pressure cylinder 36 so as to always be abutted on the insides of the another movable molds 20, 22, 24 and 26 orthogonally crossed with the one side face thereof. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous casting mold and a continuous casting method in which a slab in a state where only a surface portion is solidified by cooling in a mold (a state in which a shell is formed) is continuously drawn from a lower portion.
[0002]
[Prior art]
In the field of non-ferrous materials such as steel materials and aluminum, molten steel is cast into a vertically open mold (mold), and is cooled in the mold by a dummy head of an elevating table that can be moved up and down below the mold. With the lower end of the slab having a shell formed on the surface supported, the slab is vertically pulled down at a predetermined speed to pull out the slab vertically from the lower part of the mold to cast a slab of a predetermined length. Continuous casting devices are known.
[0003]
Here, internal defects such as center porosity, center segregation, and V-shaped segregation that occur inside the slab are defined as the angle of the solidification front surface of the molten steel in the slab (the angle with respect to the center line of the solidification interface of the molten steel = V segregation angle). ) Is believed to have affected the situation. In this case, the mold used in the conventional continuous casting apparatus is of a fixed type in which the internal dimensions are not changed during continuous casting, and the shape of a cast piece drawn from the lower part of the mold is constant (straight). Since the angle is small and the suction of molten steel in which C, S, P, etc. are concentrated is promoted, many internal defects described above are generated, and there is a problem that the product quality is reduced and the yield is reduced. I was
[0004]
Therefore, the slab drawn from the mold is deformed by applying light or strong pressure reduction using a reduction device, thereby suppressing concentrated molten steel generated at the end of solidification and reducing internal defects, or casting with an electromagnetic stirring device. Attempts have been made to reduce the internal defects by dispersing segregation by electromagnetically stirring molten steel in a piece.
[0005]
However, when the slab is rolled down, if the rolling timing and amount are not proper, internal cracks may be induced or indentation flaws may remain due to the rolling down. Further, in the case of a steel type having a high deformation resistance and a low hot ductility (for example, tool steel), an extremely large rolling capacity is required, and there is a problem that the equipment becomes heavy and the equipment cost increases. On the other hand, when using an electromagnetic stirrer, there is no induction of internal cracks and surface flaws, but when the solidified shell thickness or slab cross-sectional size is increased, the attenuation of the magnetic flux density increases, so as with the rolling down device. A high-performance device is required, which leads to an increase in equipment cost due to heavy equipment.
[0006]
As a countermeasure for the above problem, a pair of opposing movable dies constituting a mold are moved away from each other during continuous casting, so that a pair of surfaces (two surfaces) of a slab to be pulled out from a lower portion of the mold are tapered. Has been proposed by the present applicant (for example, Patent Document 1). This apparatus is designed to suppress the occurrence of internal defects such as center porosity, center segregation or V-shaped segregation by increasing the V segregation angle by imparting a taper to two surfaces of the slab, Unlike the case of using the rolling-down device or the electromagnetic stirring device, the equipment cost does not increase due to the heavy work of the device itself.
[0007]
[Patent Document 1]
JP-A-2002-361374
[Problems to be solved by the invention]
The technique disclosed in Patent Document 1 can suppress the occurrence of internal defects such as the center porosity, center segregation, and V-shaped segregation, and can be highly evaluated as such. However, in the case of steel grades that require stricter product quality, for example, special steels including high alloy steels and tool steels, the current situation is that the demands have not been sufficiently met.
[0009]
Therefore, the inventor of the present invention sought various ways to solve the above-mentioned problem, and found that the generation of internal defects could be further suppressed by imparting a taper to the four surfaces of the slab. Although Patent Document 1 discloses that it is possible to impart a taper to four surfaces of a slab, a pair of opposing movable molds constituting a mold disclosed in the document is disclosed. However, it is not possible to impart a taper to the four surfaces of the slab by a technique of simply moving the slabs away from each other, which is not feasible.
[0010]
Here, the occurrence of the internal defect also depends on the cross-sectional dimension of the cast slab, and the dimension (optimum dimension) at which the internal defect is unlikely to occur is roughly known for each steel type. For this reason, the mold used is one whose internal dimensions are set in accordance with the type of steel. If the optimum dimensions change when the steel type is changed, the mold itself is replaced. In addition, the mold exchange is also performed according to the required size of the product, and the cast slab is then processed by slab rolling, forging, etc. to a product size such as a mold steel, a flat rectangle, a bar, a wire, a plate. You. However, in the current situation where many kinds and small lots are required as in recent years, a problem is pointed out that the downtime due to the replacement of the mold becomes long and the casting ability is reduced. Therefore, if it is possible to cast a slab equivalent to the required size of various products without changing the mold, it is possible to improve the casting ability and shorten the steps of slab rolling, forging, or omit the steps. As a matter of fact, such a mold and a casting method have not been proposed yet.
[0011]
[Object of the invention]
The present invention has been proposed in view of the above-described problems inherent in the conventional technology, and has been proposed to appropriately solve the problem.The center porosity, the center segregation or the internal defects such as the V-shaped segregation are few, It is an object of the present invention to provide a continuous casting mold and a continuous casting method that can cast a slab having a tapered surface on four sides that can improve product quality and yield, and that can easily respond to dimensional changes. .
[0012]
[Means for Solving the Problems]
In order to solve the above-described problems and appropriately achieve the intended purpose, the continuous casting mold according to the present invention is:
A continuous casting mold in which molten steel is cast into a casting space defined in a square shape that opens up and down, and a slab with a shell formed on the surface is drawn from a lower portion,
The casting space is defined in such a manner that each of the four movable dies arranged in a mutually orthogonal relationship is in contact with an inner surface of another movable die having one side orthogonal to the other,
Each of the movable molds is configured to be able to advance and retreat in parallel with an actuating means with respect to the opposing movable molds,
Each of the movable dies is configured to be urged by urging means so that the one side surface is always in contact with the inner surface of another movable dies that is orthogonal to the other side surface.
[0013]
In order to solve the above-described problems and appropriately achieve the intended purpose, a continuous casting method according to another invention of the present application is:
Using the continuous casting mold, while pulling out a slab having a shell formed on the surface from the lower part of the mold, moving each pair of the four movable dies arranged in a mutually orthogonal relation to each other. Then, the four surfaces of the slab are tapered such that the opposite side dimension becomes smaller as going from the upper part to the lower part.
[0014]
In order to solve the above-described problems and appropriately achieve the intended purpose, a continuous casting method according to still another invention of the present application is provided.
Using the continuous casting mold, after positioning the relative positions of the four movable dies arranged in a mutually orthogonal relationship so that the opening dimension of the casting space has a desired cross-sectional dimension, the casting space It is characterized by casting molten steel into a steel plate and pulling out a slab having a shell formed on a surface from a lower portion to cast slabs having various desired cross-sectional dimensions.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a continuous casting mold and a continuous casting method according to the present invention will be described below with reference to the accompanying drawings by way of preferred embodiments.
[0016]
FIG. 1 shows a continuous casting mold according to an embodiment, and FIG. 4 schematically shows a continuous casting apparatus in which the continuous casting mold is implemented. The continuous casting apparatus 10 includes a continuous casting mold (hereinafter, also simply referred to as a mold) 14 that is provided on a casting bed 12 and that defines a rectangular casting space S that opens up and down. In the casting space S, molten steel is cast via a ladle 16 and a tundish 18 provided above the casting space S.
[0017]
As shown in FIG. 1, the mold 14 includes four movable dies 20, 22, 24, and 26 arranged in a mutually orthogonal relationship, and each of the four movable dies 20, 22, 24, and 26 includes: The casting space S is defined without any gap by abutting one side surface on the inner surface (the casting space S side) of another movable mold 20, 22, 24, 26 which is orthogonal. Of the four movable dies 20, 22, 24, 26, the first movable dies 20 and the second movable dies 22 facing each other in the width direction of the cast piece 28 to be cast are maintained in a parallel posture. The third movable mold 24 and the fourth movable mold 26, which are configured to be movable toward and away from each other, and are opposed to each other in the thickness direction of the slab 28, approach and separate from each other while maintaining a parallel posture. It is configured to be movable. Each of the four movable dies 20, 22, 24, 26 is movable in a direction (biasing direction) along its inner surface.
[0018]
Since the configurations of the four movable dies 20, 22, 24, and 26 and the associated mechanisms are the same, the configuration related to the first movable die 20 will be mainly described, and the other movable dies 22, 24 will be described. , 26 are denoted by the same reference numerals, and detailed description is omitted. In the embodiment, in FIG. 1, the third movable mold 24, the second movable mold 22, and the fourth movable mold 26 are arranged in the order clockwise with respect to the first movable mold 20.
[0019]
On the outer surface of the first movable die 20, a slider 30 that is movable in a biasing direction (direction along the inner surface of the second movable die 22) orthogonal to the moving direction of the movable die 20 is provided. . The slider 30 is connected to a screw jack 32 as operating means disposed on the casting bed 12, and by rotating a drive motor 34 of the jack 32 forward and backward, the first movable mold 20 is opposed to the first movable mold 20. To move back and forth in parallel with the second movable mold 22. That is, by moving each pair of the first movable mold 20 and the second movable mold 22 and the third movable mold 24 and the fourth movable mold 26 away from each other, the opening dimension of the casting space S is increased. Can be gradually increased (see FIG. 2).
[0020]
On the outer surface of the first movable mold 20, a first hydraulic cylinder 36 using a hydraulic pressure or the like as an urging means is provided in a posture in which a piston rod 36a extends and contracts in the urging direction. The distal end of the rod 36a is connected to the slider 30. When the first fluid pressure cylinder 36 is urged in a predetermined direction, the first movable mold 20 moves in the urging direction with respect to the slider 30, and the one side surface is moved to another movable mold (first In the case of the movable mold 20 of the fourth embodiment, the movable mold 20 is configured to be able to always contact the inner surface of the fourth movable mold 26). Incidentally, one side surface of the second movable die 22 is the inner surface of the third movable die 24, one side surface of the third movable die 24 is the inner surface of the first movable die 20, and one side surface of the fourth movable die 26 is The second movable mold 22 is set so as to come into contact with the inner surface thereof. That is, when the fourth movable die 26 moves away from the third movable die 24 so as to increase the opening dimension of the casting space S, the fourth movable die 26 is moved from one side surface of the first movable die 20. Although the inner surface is separated to form a gap, in the embodiment, the first side surface is always in contact with the inner surface of the fourth movable mold 26 by moving the first movable mold 20 in the biasing direction with respect to the slider 30. Gaps can be prevented. The first fluid pressure cylinder 36 may be configured such that the cylinder 36 is disposed on the slider 30 and the piston rod 36a is connected to the first movable die 20.
[0021]
The pressure at which one side surface of the first movable mold 20 is brought into contact with the inner surface of the fourth movable mold 26 by the first fluid pressure cylinder 36 is set so that the first movable mold 20 is close to the second movable mold 22. When moving in the separating direction (forward / backward direction), the value is set to a value that does not cause a gap between one side surface and the inner surface and does not cause a large resistance of the movement of the first movable mold 20. At least the inside of each of the movable dies 20, 22, 24, 26 that defines the casting space S is made of, for example, copper, which has good heat conduction and heat resistance, and has a smooth sliding surface. It is formed to be movable and flat.
[0022]
Then, as will be described later, while pulling the cast piece 28 from the lower part of the mold 14, each pair of the four movable dies 20, 22, 24, 26 is moved away from each other, and the movable dies 20, 22, 24, 26 By energizing one side surface so as to abut against the inner surfaces of the other movable dies 20, 22, 24, 26, the opening size of the casting space S gradually increases without gaps at the corners. A taper is applied to both sides (two opposing surfaces) in the width direction and the thickness direction of the slab 28 drawn from the mold 14 so that the width and the thickness dimension (the opposite side dimension) of both sides decrease from the upper part to the lower part. (See FIG. 5). The taper applied to the slab 28 is in the range of 4 to 30 mm per meter in actual operation.
[0023]
As shown in FIG. 3, the lower part of the first movable mold 20 approaches and separates from the surface of the slab 28, which is primarily cooled in the mold 14 and has an outer shell formed on the surface. A regulating member 38 that can be tilted in the direction is provided, and a plurality of rolls 40 are freely rotatably arranged on a surface of the regulating member 38 facing the surface of the slab 28. A second hydraulic cylinder 42 using hydraulic pressure or the like as a second urging means is disposed on an outer surface at a lower end portion of the first movable mold 20, and its piston rod 42 a is connected to the regulating member 38. The second fluid pressure cylinder 42 is urged in a direction in which the piston rod 42a extends, so that the roll 40 of the regulating member 38 is brought into contact with the surface of the cast piece 28. That is, the rolls 40 of the regulating members 38 disposed on the respective movable dies 20, 22, 24, 26 are pressed against the four surfaces of the slab 28 immediately after being pulled out from the lower part of the mold 14, whereby the slab 28 is pressed. The bulging of the slab 28 can be prevented. During the continuous casting, the second hydraulic cylinder 42 is controlled so that the regulating member 38 always contacts the slab 28 at a predetermined pressure.
[0024]
Each of the movable dies 20, 22, 24, and 26 is formed to be hollow, and has a water cooling structure in which cooling water is supplied from an external supply source. The mold 14 is vertically moved by an oscillation device (not shown) so as to reduce friction between the casting piece 28 drawn from the lower part of the mold 14 and the mold 14 and prevent seizure. Have been.
[0025]
As shown in FIG. 4, a plurality of nozzles 44 vertically spaced apart from each other are disposed below the mold 14 so as to face each other in the width direction with the slab 28 interposed therebetween. By spraying cooling water (water) directly toward the slab 28, secondary cooling for promoting solidification of the slab 28 is performed. The nozzle 44 is configured to be retractable to a position that does not interfere with a lifting table 48 described later, and allows the lifting table 48 to move up and down between the nozzles 44 facing each other in the width direction.
[0026]
Below the mold 14, an elevating table 48 provided with a dummy head 46 for supporting the lower end of the cast piece 28 is arranged vertically vertically. In addition, pulleys 50, 50 are rotatably disposed on both sides of the slab 28, and a wire 52 having one end connected to an appropriate fixing portion is wound around the pulleys 50, 50, and the other end is free. It is connected to a winch 54 that can be shifted. The elevator 48 is suspended and supported by a wire 52 facing between the pulleys 50, 50, and the elevator 48 made of the wire 52 and the winch 54 is moved up and down. That is, by rotating and driving the winch 54 in the direction in which the wire 52 is wound up, the lift 48 is raised via the wire 52, and conversely, by rotating and driving the winch 54 in the direction in which the wire 52 is fed out, the wire The elevating platform 48 is configured to move down via 52.
[0027]
Operation of the embodiment
Next, the operation of the continuous casting mold according to the above-described embodiment will be described in connection with the continuous casting method in a case where the four surfaces of the slab 28 drawn by the mold 14 are tapered. The respective pairs of the first movable mold 20 and the second movable mold 22 and the third movable mold 24 and the fourth movable mold 26 in the mold 14 are brought close to each other (see FIG. 1), and the casting is performed. While reducing the opening size of the space S, the winch 54 is driven to rotate in a predetermined direction to raise the elevating table 48, and the ladle 16 and the tundish are closed with the dummy head 46 closing the lower part of the mold 14. The molten steel is cast into the casting space S of the mold 14 via 18. A shell is formed on the surface of the molten steel cast into the mold 14 by primary cooling by the mold 14. In addition, the winch 54 is driven in reverse to vertically lower the elevating table 48 at a predetermined casting speed, whereby the cast piece 28 whose lower end is supported by the dummy head 46 is pulled out from the lower part of the mold 14.
[0028]
The slab 28 immediately after being pulled out from the mold 14 is pressed from four directions by the roll 40 of the regulating member 38 disposed on the movable dies 20, 22, 24, 26, thereby causing bulging. Is prevented. Further, cooling water is sprayed onto the slab 28 from the plurality of nozzles 44, 44, and the slab 28 is secondarily cooled.
[0029]
Each pair of the first movable mold 20 and the second movable mold 22 and the third movable mold 24 and the fourth movable mold 26 constituting the mold 14 is The first fluid pressure cylinders 36 move away from each other under the urging force, and the opening size of the casting space S gradually increases (see FIG. 2). At this time, each of the first fluid pressure cylinders 36 disposed on each of the movable dies 20, 22, 24, and 26 is urged to move the corresponding one of the movable dies 20, 22, 24, and 26 with respect to the slider 30. Is moved in the biasing direction, so that one side thereof abuts against the inner surfaces of the other movable dies 20, 22, 24, 26. That is, when each of the movable dies 20, 22, 24, and 26 moves in the forward and backward directions, one side surface of the movable dies 20, 22, 24, and 26 always moves in contact with the inner surface of the other movable dies 20, 22, 24, and 26. There is no gap at each corner of the space S.
[0030]
As described above, the slab 28 drawn from the lower part of the mold 14 that moves the four movable dies 20, 22, 24, 26 to gradually increase the opening size of the casting space S has a width direction and a thickness direction. Each of the two side surfaces is provided with a required taper whose width and thickness decrease from the upper part to the lower part (see FIG. 5). In the slab 28 having four surfaces tapered, the occurrence of internal defects such as center porosity, center segregation and V-shaped segregation is suppressed, and high quality and improved yield are obtained. It has become. That is, the mold 14 of the embodiment is particularly effective in casting of a steel type requiring strictness, such as special steel including high alloy steel and tool steel. It should be noted that other steel grades are also suitably improved in quality. Further, since the mold 14 of the embodiment has a simple configuration in which only four movable dies 20, 22, 24, 26 are combined, the equipment cost does not increase.
[0031]
Here, as described above, since the occurrence of internal defects also depends on the cross-sectional dimension of the slab 28, it is necessary to optimize the BOT dimension and the TOP dimension of the slab 28 for each steel type. In this case, the mold 14 of the embodiment can move the four movable dies 20, 22, 24, and 26 to an arbitrary position. Therefore, it is possible to cast the slab 28 of the optimum size without replacing the mold itself. Can be. Also, regarding the taper, an arbitrary taper angle can be given to the cast piece 28 by variably controlling the amount of movement of the movable molds 20, 22, 24, 26 during casting. Furthermore, regarding the cross section of the cast piece 28, if the positional relationship between the movable dies 20, 22, 24, and 26 is changed, the cross section can be made not only a square but also a rectangle. Furthermore, the amount of movement of the first movable mold 20 and the second movable mold 22 facing each other in the width direction of the slab 28 during casting, and the third movable mold 24 and the fourth movable mold 24 facing each other in the thickness direction. By changing the amount of movement during casting with the movable mold 26, the angle of the taper applied to the surface opposing the width direction of the slab 28 is different from the angle of the taper applied to the surface opposing the thickness direction. It can also be done.
[0032]
As described above, the mold 14 of the embodiment can move and move the four movable dies 20, 22, 24, and 26 to an arbitrary position. In the case of casting a piece, when the optimum dimensions are changed due to the change of the steel type, or when the required product size is changed, the four movable dies 20, 22, 24, 26 are moved to change the relative position, This can be dealt with simply by positioning the casting space S at a position where the opening dimension of the casting space S has a desired cross-sectional dimension such as an optimum dimension or a required size. That is, a single mold 14 can be used to cast slabs 28 of various cross-sectional dimensions without having to replace a mold set in accordance with the optimum dimensions and the required size of the product as in the prior art. It is possible to cope with requests for many kinds and small lots without lowering the casting ability. In addition, since it is possible to cast slabs 28 corresponding to the required sizes of various products without replacing the mold 14, it is possible to shorten the subsequent steps of slab rolling, forging, or omit the steps. Furthermore, since it is not necessary to prepare different molds for each required size of the steel type or the required product size, the equipment cost can be reduced and the storage and management can be simplified.
[0033]
[Experimental example]
As described above, the occurrence of internal defects such as the center porosity, center segregation and V-shaped segregation is affected by the angle of the solidification front surface of molten steel in the slab (the angle with respect to the center line of the solidification interface of molten steel = V segregation angle). Is believed to be. Therefore, the V segregation angle with respect to the distance from the slab TOP was measured for each of Conventional Examples 1 and 2 where the slab was not tapered and Conventional Examples 2 and 4 where the tapered surface was provided. The result is shown in FIG. The taper applied to the slab was 4 mm / m.
[0034]
From the above results, in the case of Conventional Example 1, the V segregation angle was small, and the suction of molten steel in which C, S, P and the like were concentrated was promoted, and thus the internal defects were generated in large numbers. On the other hand, when the taper is applied to two or four surfaces as in Conventional Example 2 or Invention Example, the V segregation angle increases because the upper width increases near the solidification interface. It was confirmed that the suction of molten steel in which S, P, etc. were concentrated was reduced, and the occurrence of the internal defects was suitably suppressed.
[0035]
Next, with respect to the conventional example 1, the conventional example 2, and the invention example, the temperature gradient inside the billet was measured, and the result is shown in FIG. From these results, in the case of the invention example in which the four surfaces of the slab are tapered, a large vertical temperature gradient is formed due to the decrease in the cross-sectional area of the bottom end (BOT) of the slab, and the upper directivity is increased. Solidification (laminated solidification) is promoted and side solidification is avoided. Thus, it was confirmed that the continuation of the Zaku and V-shaped segregation in the center direction was suppressed, and further suppression of internal defects was achieved as compared with Conventional Example 2.
[0036]
[Modification example]
The actuating means for moving the movable mold in the mold is not limited to the screw jack of the embodiment, but may be an actuator such as a fluid pressure cylinder. Further, the biasing means for abutting one side surface of the movable mold on the inner surface of another movable mold and the second biasing means for abutting the regulating member on the surface of the cast piece are also limited to the fluid pressure cylinder of the embodiment. Instead, various mechanisms such as a ball screw and a screw screw or a rack-pinion operated by a motor can be employed. In the embodiment, a roll is disposed on the regulating member, and the roll is configured to abut on the slab. However, if the slab is smoothly pulled out and the surface thereof is not damaged, the regulating member is directly connected to the slab. May be contacted.
[0037]
【The invention's effect】
As described above, according to the continuous casting mold and the continuous casting method according to the present invention, there are few internal defects such as center porosity, center segregation or V-shaped segregation, and high-quality and tapered four surfaces capable of improving the yield. Can be cast. In addition, since the opening size of the casting space is configured to be arbitrarily changeable by moving the four movable dies, the opening size of the casting space can be easily changed to an optimum size according to the type of steel. The taper angle given to the piece can also be set arbitrarily. In the case of casting a straight slab without imparting a taper to the slab, when the optimum dimensions are changed or when the required product size is changed, a short time without replacing the mold itself is required. And the casting ability can be improved, and the post-process can be shortened or omitted. Furthermore, bulging can be prevented from occurring by configuring the regulating member to contact the surface of the slab that is drawn from the lower part of the mold.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing a continuous casting mold according to a preferred embodiment of the present invention in a state where the casting space is reduced.
FIG. 2 is a schematic plan view showing a continuous casting mold according to an example in a state where a casting space is enlarged;
FIG. 3 is a main part front view showing a movable mold and a regulating member of the continuous casting mold according to the embodiment.
FIG. 4 is a schematic configuration diagram showing a continuous casting apparatus in which a continuous casting mold according to an embodiment is implemented.
FIG. 5 is a schematic perspective view showing a slab cast by a continuous casting mold according to an example.
FIG. 6 is a graph showing a result of measuring a V segregation angle.
FIG. 7 is a graph showing a result of measuring an internal temperature gradient of a slab.
[Explanation of symbols]
Reference Signs List 20 first movable die 22 second movable die 24 third movable die 26 fourth movable die 28 slab 32 screw jack (operating means)
36 first fluid pressure cylinder (biasing means)
38 regulating member 42 second fluid pressure cylinder (second urging means)
S casting space

Claims (4)

A continuous casting mold in which molten steel is cast into a casting space (S) defined in a square shape that opens up and down, and a slab (28) having a shell formed on the surface is drawn from a lower portion,
In the casting space (S), each of the four movable dies (20, 22, 24, 26) arranged in a mutually orthogonal relationship has another movable die (20, 22, 24, 26) is defined in contact with the inner surface of
Each of the movable dies (20, 22, 24, 26) is configured to be able to advance and retreat in parallel to the opposing movable dies (20, 22, 24, 26) by operating means (32),
Each of the movable molds (20, 22, 24, 26) is biased by a biasing means (36) so that the one side surface is always in contact with the inner surface of another movable mold (20, 22, 24, 26) orthogonal to the movable mold. A continuous casting mold characterized by being configured to be energized. A regulating member (38) urged by a second urging means (42) to always contact the surface of the slab (28) is provided below the movable dies (20, 22, 24, 26). 2. The continuous casting mold according to claim 1, wherein the casting mold is tiltably disposed. 3. The four movable dies (4) which are arranged in a mutually orthogonal relationship while pulling a slab (28) having a shell formed on a surface thereof from a lower part of the mold using the continuous casting mold according to claim 1 or 2. 20, 22, 24, and 26), the four surfaces of the slab (28) are tapered so that the paired sides become smaller in size from the upper part to the lower part by moving away from each other. A continuous casting method characterized by the following. The relative position of the four movable dies (20, 22, 24, 26) arranged in a mutually orthogonal relationship using the continuous casting mold according to claim 1 or 2 is set to the position of the casting space (S). After positioning so that the opening dimension has a desired cross-sectional dimension, molten steel is cast into the casting space (S), and a cast slab (28) having a shell formed on the surface is pulled out from a lower portion to obtain a desired shape. A continuous casting method characterized by casting slabs (28) having various cross-sectional dimensions.

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