JP7172432B2 - Partition plate for continuous casting of different steel grades and method for continuous casting of different steel grades - Google Patents

Description

TECHNICAL FIELD The present invention relates to a partition plate for continuous casting of different steel grades, which is used when continuously casting molten steel of different grades, and a continuous casting method for different steel grades using the partition plate for continuous casting of different steel grades.

In the continuous casting process of steel production, it is used to remove inclusions such as oxides from the molten steel that cause deterioration in the strength, workability, fatigue resistance, etc. of steel materials, and to facilitate processing in the rolling process. A semi-finished product with a certain shape is produced. In such continuous casting, when two types of molten steel of different steel grades are continuously injected into the mold, the components of the two molten steels are mixed at the interface between the respective molten steels, and none of the steel grades satisfy the product standards, resulting in scrap as scrap. A mixed zone is created that must be discarded.

Conventionally, in order to suppress the mixing of components in the continuous casting of molten steel of different steel types, it has been practiced to insert a partition plate between each molten steel in the mold to partition the molten steel and to make the mixing area as small as possible. It is

In Patent Document 1, as a continuous casting method for molten steel of different steel types, after the injection of the previous molten steel (first molten steel) is completed, a V-shaped partition plate for partitioning different steel types is inserted into the mold, A method of injecting post-molten steel (second molten steel) into the mold through the partition plate is disclosed. This eliminates the need to replace the tundish (an intermediate vessel between the ladle and the mold) when continuously casting molten steel of different steel grades, enabling continuous casting of different steel grades, reducing costs and operating time. be able to.

JP-A-2-197355

The partition plate for continuous casting of different steel grades described in Patent Document 1 is designed to prevent the partition plate from contacting the inner wall of the mold and to prevent interference with the solidified shell formed in the mold. It is formed in such a size that a gap is generated between the inner wall surface of the mold and the partition plate. When the second molten steel is injected in a state in which the gap exists in this way, the second molten steel advances below the partition plate through the gap and becomes easier to mix with the first molten steel. As a result, the mixed region where the first molten steel and the second molten steel are mixed becomes longer, that is, the defective part as a product may become longer. Therefore, there is room for improvement in the partition plate for continuous casting of different steel grades described in Patent Document 1.

The present invention has been made in view of this point, and an object of the present invention is to shorten the length of the mixing zone where the components of the molten steel are mixed when continuously casting different types of molten steel.

In order to achieve the above object, the present invention provides a partition plate for continuous casting of different steel grades, which is used in a mold when continuously casting molten steels of different steel grades, comprising a main body portion extending in the horizontal direction; and a vertical plate portion extending vertically upward from the main body, wherein one end of the support is connected to the main body. The other end of the support is located above the bottom surface of the main body, and the support is inclined upward from the longitudinal end of the main body. provided, the inclination angle of the support from the horizontal direction is 30 to 60 degrees, and the support has a flow rate of molten steel flowing through the gap between the other end of the support and the mold, The point of maximum flow velocity of the molten steel in the mold is shifted upward from the bottom surface of the main body, and is smaller than the opening of the mold in plan view.

According to the present invention, the other end of the support provided at both ends of the main body is located above the bottom surface of the main body. The flow velocity of the molten steel flowing through the gap between the other end of the mold and the short side wall of the mold) can be shifted upward. As a result, the length of the downward flow from the maximum flow velocity point can be shortened, that is, the mixing area of the first molten steel injected earlier and the second molten steel injected later can be narrowed. The details of the flow of molten steel in the mold in the present invention will be described in the embodiments.

The body portion may have a V-shape in a cross section perpendicular to the longitudinal direction.

The support portion may be detachably attached to the main body portion.

The body portion may be detachably suspended from the bottom portion of the tundish.
Further, the other end of the support may be located 100 mm or more above the bottom surface of the main body.

According to another aspect of the present invention, there is provided a partition plate for continuous casting of different steel grades, which is used in a mold when continuously casting molten steels of different grades, comprising a main body portion extending in the horizontal direction and a longitudinal direction of the main body portion. It has a plate-shaped support provided at both ends in the direction, and a vertical plate provided by extending vertically upward from the main body, and one end of the support is provided on a side surface of the vertical plate. The other end of the support is located 100 mm or more above the bottom surface of the main body, and the support flows through the gap between the other end of the support and the mold. and the maximum flow velocity point of the molten steel in the mold is shifted upward from the bottom surface of the main body and is smaller than the opening of the mold in plan view.
According to another aspect of the present invention, there is provided a method for continuous casting of different steel grades, in which molten steels of different steel grades are continuously cast using the partition plate for continuous casting of different steel grades, the step of pouring a first molten steel into the mold. a step of inserting the partition plate for continuous casting of different steel grades into the mold; and a step of pouring a second molten steel into the mold.

ADVANTAGE OF THE INVENTION According to this invention, the length of the mixing area|region where the component of molten steel mixes can be shortened in casting the molten steel of a different steel grade continuously.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which showed typically the outline of a structure of the continuous casting equipment provided with the partition plate concerning this embodiment. It is an explanatory view of a cross section showing an outline of a structure of a casting mold and an immersion nozzle. It is an explanatory view of a longitudinal section showing an outline of a configuration of a partition plate, a mold, an immersion nozzle and a tundish. It is an explanatory view of a longitudinal section showing an outline of a configuration of a partition plate, a mold, an immersion nozzle and a tundish. FIG. 2 is a perspective view schematically showing the outline of the configuration of the partition plate according to the embodiment; FIG. 4 is an explanatory view schematically showing a step of inserting a partition plate into a mold in continuous casting of molten steel of different steel grades; It is an explanatory view showing the flow of molten steel in the mold. It is a graph which shows the mixing ratio of the 2nd molten steel with respect to the 1st molten steel in a mold. It is a graph which shows the depth which the mixing ratio of 2nd molten steel with respect to 1st molten steel becomes 0.2 in a mold. FIG. 11 is a perspective view schematically showing the outline of the configuration of a partition plate according to another embodiment; FIG. 11 is a perspective view schematically showing the outline of the configuration of a partition plate according to another embodiment; FIG. 11 is a perspective view schematically showing the outline of the configuration of a partition plate according to another embodiment; FIG. 11 is a perspective view schematically showing the outline of the configuration of a partition plate according to another embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, thereby omitting redundant description.

<Configuration of continuous casting equipment>
First, the configuration of a continuous casting facility 1 equipped with a partition plate for continuous casting of different steel grades (hereinafter referred to as a partition plate) according to an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram showing the outline of the configuration of a continuous casting facility 1. As shown in FIG. In addition, in the following description, in the continuous casting equipment 1, the case where the molten steel (the 1st molten steel 4a and the 2nd molten steel 4b which are mentioned later) which differ in steel grades is continuously cast is demonstrated.

As shown in FIG. 1, a continuous casting facility 1 includes a tundish 2 for storing molten steel, an immersion nozzle 5 for injecting a first molten steel 4a and a second molten steel 4b of different steel grades from the bottom of the tundish 2 into a mold 3, A pair of roll groups 7, 7 are provided for passing the cast slab 6 pulled out from the mold 3. In the roll group 7 , a plurality of reduction rolls 8 for guiding the slab 6 are arranged side by side in the casting direction of the slab 6 .

The tundish 2 is provided with an elevating mechanism (not shown) such as an actuator for moving the tundish 2 in the thickness direction of the mold 3, that is, in the vertical direction. As a result, the tundish 2 is integrated with the submerged nozzle 5 provided at the bottom so as to be movable in the vertical direction, and the submerged nozzle 5 is configured to move forward and backward with respect to the mold 3 .

As shown in FIG. 2, the mold 3 has, for example, a substantially rectangular horizontal cross-sectional shape with a pair of long side walls 10,10 and a pair of short side walls 11,11. An immersion nozzle 5 and a partition plate 100, which will be described later, are inserted into the mold 3, and the first molten steel 4a and the second molten steel 4b are discharged from a discharge port 50, which is formed near the lower end of the immersion nozzle 5. injection is performed.

As shown in FIGS. 3 and 4, the upper portion of the mold 3 is provided with an immersion nozzle 5 communicating with the bottom portion of the tundish 2 . Two discharge ports 50 for discharging the first molten steel 4a and the second molten steel 4b obliquely downward into the mold 3 are provided near the lower end of the side surface of the submerged nozzle 5 so as to face the short side wall 11 of the mold 3. formed. The molten steel flow F1 discharged obliquely downward from the discharge port 50 collides with the solidified shell 30 solidified on the short side wall 11 of the mold 3 by cooling the molten steel, for example, and forms an ascending molten steel flow F2 and a descending molten steel flow. Branch to F3. The molten steel flow F1 contains inclusions 31 such as alumina and slag. The inclusions 31 float to the vicinity of the meniscus 32 by, for example, the rising molten steel flow F2. A molten powder 33 having a molten oxide is supplied onto the meniscus 32 .

Below the immersion nozzle 5, a partition plate 100 is provided which is inserted substantially horizontally into the mold 3 and which suppresses mixing of the first molten steel 4a and the second molten steel 4b. As shown in FIG. 5 , the partition plate 100 has a body portion 101 , a support portion 102 and a vertical plate portion 103 .

The body portion 101 extends in the horizontal direction in its longitudinal direction and has, for example, a V-shape in a cross section perpendicular to the longitudinal direction. Then, the body portion 101 is inserted into the mold 3 substantially horizontally. Here, if there is an inclusion 31 below the main body portion 101, there is a risk that the connectivity in the first molten steel 4a or the second molten steel 4b will deteriorate. In this respect, in this embodiment, the main body portion 101 has a V shape, so the inclusions 31 can be removed. However, the lateral side shape of the body portion 101 is not limited to the V shape, and may be, for example, a semicircular shape or a flat plate shape.

The support portions 102 are provided at both ends in the longitudinal direction of the main body portion 101 . One end portion 102 a of the support portion 102 is connected to the longitudinal end portion of the main body portion 101 . The other end portion 102 b of the support portion 102 is located above the bottom surface of the main body portion 101 . The support portion 102 is provided so as to be inclined upward from the end portion of the main body portion 101 in a longitudinal side view. The angle of inclination of the support 102 from the horizontal direction is preferably 30 to 60 degrees as will be described later. In addition, the supporting body part 102 has, for example, a V-shaped shape in a cross section perpendicular to the longitudinal direction, similarly to the main body part 101 . However, the lateral side shape of the support portion 102 is not limited to the V shape, and may be, for example, a semicircular shape or a flat plate shape.

The vertical plate portion 103 extends vertically upward from the main body portion 101 in a state of being inserted into the mold 3 . The vertical plate portion 103 is suspended from an attachment jig 20 provided on the bottom of the tundish 2 via a suspension shaft 104 and a suspension tool 105 . The suspension shaft 104 and the suspension tool 105 are provided above the vertical plate portion 103 (on the mounting jig 20 side). The mounting jig 20 has a fixing member 21 , a support member 22 that is rotatable with respect to the fixing member 21 , a hollow member 23 that holds the suspension shaft 104 , and a hook 24 that suspends the suspension tool 105 . The partition plate 100 is configured to be rotatable and detachable between the mounting jig 20 and the vertical plate portion 103 .

As shown in FIG. 2, the partition plate 100 (main body portion 101, supporting body portion 102) is arranged at the opening of the mold 3 (a pair of long sides It is formed to be smaller than the range surrounded by the walls 10, 10 and the pair of short side walls 11, 11). Between the ends of the partition plate 100 and the long side walls 10, 10 of the mold 3, gaps 10a, 10a are formed. Further, gaps 11a, 11a are formed between the other end portion 102b of the support portion 102 and the short side walls 11, 11. As shown in FIG.

<Continuous casting method for molten steel of different steel types>
Next, a method of continuously casting the first molten steel 4a and the second molten steel 4b of different steel grades using the continuous casting facility 1 configured as described above will be described. Specifically, the process of pouring the first molten steel 4a and the second molten steel 4b from the tundish 2 into the mold 3 will be described.

First, the first molten steel 4a is poured while the partition plate 100 is retracted outside the mold 3 as shown in FIG. 6(a). Subsequently, when the injection of the first molten steel 4a is completed, the tundish 2 is lifted by a lifting mechanism (not shown) as shown in FIG. 6(b) before the injection of the second molten steel 4b. The partition plate 100 attached to the jig 20 is lifted together, and the partition plate 100 is arranged above the opening of the mold 3 . After that, the tundish 2 is lowered by the lifting mechanism and the partition plate 100 is inserted into the mold 3 as shown in FIG. 6(c). When the partition plate 100 is inserted to a predetermined position in the mold 3, the partition plate 100 is removed from the mounting jig 20 as shown in FIG. Injection of molten steel 4b is started. Also, the removed partition plate 100 descends at the casting speed.

Next, based on FIG. 7, the flow in the mold 3 of the second molten steel 4b injected from the discharge port 50 will be described. 7(a) and 7(b) show the conventional partition plate 500, that is, the partition plate 500 consisting of only the main body portion 501 without the support portion and the vertical plate portion 503, immediately after being inserted into the mold 3 (FIG. 7(a)). )), and the state (FIG. 7B) after a certain period of time has passed since the partition plate 500 was inserted. 7C and 7D show the partition plate 100 according to the present embodiment, that is, immediately after the partition plate 100 having the main body portion 101, the support portion 102 and the vertical plate portion 103 is inserted into the mold 3 (FIG. 7D). 7(c)), and a state (FIG. 7(d)) after a certain period of time has elapsed since the partition plate 100 was inserted.

First, as a comparative example of the present embodiment, the flow of the second molten steel 4b when the conventional partition plate 500 is put into the mold 3 will be described with reference to FIGS. 7(a) and 7(b).

As shown in FIG. 7A, the molten steel flow G1 of the second molten steel 4b discharged from the discharge port 50 of the submerged nozzle 5 is discharged obliquely downward into the mold 3, and the molten steel rises by the vertical plate portion 503. It branches into a flow G11 and a molten steel flow G12 that descends and diffuses toward the center. The molten steel flow G12 advances below the partition plate 500 through the gap 10a formed between the long side of the main body portion 501 of the partition plate 500 and the long side wall 10 of the mold 3 to form the molten steel flow G13. .

After a certain period of time has passed since the injection of the second molten steel 4b was started, the partition plate 500 descends inside the mold 3 as shown in FIG. 7(b). In this state, the molten steel flow G1 discharged from the submerged nozzle 5 reaches the short side wall 11 of the mold 3, where it branches into an ascending molten steel flow G2 and a descending molten steel flow G3. become. The molten steel flow G3 advances below the partition plate 500 through the gap 11a formed between the short side wall 11 and the partition plate, and forms a molten steel flow G4 along the short side wall 11.

The flow velocity of the second molten steel 4b is highest in the gap 11a between the longitudinal end of the partition plate 500 and the short side wall 11, that is, in the gap 11a where the flow path is restricted, and attenuates after passing through the partition plate 500. While moving downward, it advances to the side of the first molten steel 4a. That is, the first molten steel 4a and the second molten steel 4b are mixed by the molten steel flow G4, and a mixed region that becomes a defective portion is generated.

A part of the molten steel flow G4 advances below the partition plate 500 and then diffuses toward the center of the mold 3 along the longitudinal direction (horizontal direction) of the partition plate 500 (molten steel flow G5). In the vicinity of the center of the side wall 10, the molten steel flows upward through the gap 10a (molten steel flow G6), and the molten steel flow G6 contributes to the shortening of the mixing zone.

Next, the flow of the second molten steel 4b when the partition plate 100 according to the present embodiment is put into the mold 3 will be described with reference to FIGS. 7(c) and 7(d).

As shown in FIG. 7(c), the flow of the second molten steel 4b immediately after the partition plate 100 is inserted into the mold 3 is substantially the same as the flow of the second molten steel 4b shown in FIG. 7(a). . That is, as shown in FIG. 7(c), the molten steel flow F1 by the second molten steel 4b discharged from the discharge port 50 of the submerged nozzle 5 is discharged obliquely downward into the mold 3 and rises by the vertical plate portion 103. It branches into a molten steel flow F11 and a molten steel flow F12 that descends and diffuses toward the center. The molten steel flow F12 advances below the partition plate through the gap 10a formed between the long side of the main body 101 of the partition plate 100 and the long side wall 10 of the mold 3 to form the molten steel flow F13.

After a certain period of time has elapsed since the injection of the second molten steel 4b was started, the partition plate 100 descends inside the mold 3 as shown in FIG. 7(d). In this state, the molten steel flow F1 discharged from the submerged nozzle 5 reaches the short side wall 11 of the mold 3, where it branches into an ascending molten steel flow F2 and a descending molten steel flow F3. become. The molten steel flow F3 advances below the partition plate 100 through the gap 11a formed between the short side wall 11 and the other end portion 102b of the support portion 102 of the partition plate 100, and reaches the short side wall 11. A molten steel flow F4 is formed along.

The flow velocity of the second molten steel 4b is highest between the other end portion 102b of the support portion 102 and the short side wall 11, that is, in the gap 11a where the flow path is restricted, and after passing through the partition plate 100 It advances toward the lower first molten steel 4a side while attenuating. At this time, in this embodiment, since the supporting body portion 102 is inclined with respect to the main body portion 101, the height position of the gap 11a is moved upward compared to the conventional case. As a result, the maximum flow velocity point of the second molten steel 4b can be moved upward, that is, the flow of the second molten steel 4b can be damped from above, and the first molten steel 4a and the second molten steel 4b can be shortened.

Further, part of the molten steel flow F4 advances below the partition plate 100 and then diffuses toward the center of the mold 3 along the inclination of the support portion 102 of the partition plate 100 (molten steel flow F5). In the vicinity of the center of the long side wall 10, the molten steel flows upward through the gap 10a (molten steel flow F6). Here, since the second molten steel 4b is diffused toward the central portion along the inclination, the molten steel flow F5 toward the center of the mold 3 can be formed vertically upward compared to the conventional molten steel flow G5. As a result, the mixing region of the first molten steel 4a and the second molten steel 4b can be shortened.

In addition, as described above, it is preferable that the supporting body 102 is arranged with an inclination angle of 30 to 60 degrees from the horizontal direction with respect to the main body 101 . If the inclination angle of the support body 102 is less than 30 degrees, the relative position between the position of the gap 11a between the partition plate 100 and the mold 3 and the bottom surface of the main body 101, that is, the height difference cannot be increased. , the molten steel flow F4 after passing through the gap 11a separates from the supporting body 102, making it difficult to guide the second molten steel 4b toward the center along the slope. On the other hand, if the inclination angle of the support portion 102 is greater than 60 degrees, the molten steel flow F5 tends to flow along the inclination of the support portion 102. The distance from the other end portion 102b increases, and the effect of damping the molten steel flow F4 decreases. Therefore, by setting the inclination of the support portion 102 in the range of 30 to 60 degrees, the mixing region of the first molten steel 4a and the second molten steel 4b can be further shortened.

<Effects of this embodiment>
Next, a verification example for confirming the effect of the partition plate 100 according to the above embodiment will be shown. In this verification example, the partition plate 100 in which the horizontal range of the support portion 102 in the partition plate 100 is 100 mm and the inclination angle of the support portion 102 from the horizontal direction is 45 degrees is used as the present embodiment. Then, the first molten steel 4a and the second molten steel 4b were continuously cast, and the component mixture of the molten steel was investigated. In addition, as a conventional example which is a comparative example, the partition plate 500 was used to investigate the compositional mixture of different types of molten steel. For the investigation, simulation was performed using general-purpose fluid analysis software.

FIG. 8 is a line graph showing the results of this verification. The vertical axis of each graph in FIGS. 8A to 8D is the mixing ratio of the second molten steel 4b to the first molten steel 4a 5 minutes after the start of pouring, and the horizontal axis is the main body of the partition plate 100. It is the distance from the bottom surface of 101 to the vertically downward direction. "Width" in FIG. 8 represents the width in the longitudinal direction of the mold 3. For example, "width center" is the center of the long side wall 10, and "width 3/8", "width 1/4", "width 1/8" indicates the position on the long side wall 10 with reference to the width center (long side wall 1/2).

As shown in FIG. 8, it can be seen that the mixing ratio is lower at any point on the long side wall 10 in the mold 3 in this embodiment than in the conventional case. For example, looking at the distance from the partition plate 100 where the mixing ratio at the width center is 0.1 (the mixing ratio of the second molten steel 4b is 10%), that is, the length of the mixing zone, the conventional mixing ratio is 0.1. was about 1.3 m, in this embodiment it is about 0.8 m. Thus, by providing the partition plate 100 with an inclined portion like the support portion 102, the mixing area can be shortened.

9(a) and 9(b) show the results of this verification, the depth at which the mixing ratio is 0.2 (the distance from the bottom of the partition plate 100) five minutes after the start of pouring the second molten steel 4b. ) is a bar graph. 9(a) shows that the distance from the short side wall 11 of the mold 3 to the other end 102b of the support 102 (in the conventional example, the distance from the short side wall 11 to the end of the partition plate 500) is 75 mm, and FIG. 9B shows the results when the distance is 175 mm. Note that the mixing ratio of 0.2 is, for example, a permissible mixing ratio as a product standard.

As shown in FIG. 9A, when the distance from the short side wall 11 to the end of the support 102 is 75 mm in this embodiment, the mixing ratio becomes 0.2 after 5 minutes from the start of injection. The depth is reduced by about 0.35 m compared to the case where the conventional partition plate 500 is used, that is, compared to the case where the support body 102 is not provided. Further, as shown in FIG. 9B, when the distance from the short side wall 11 to the end of the support portion 102 is set to 175 mm in the present embodiment, compared with the case where the conventional partition plate 500 is used, approximately Shortened by more than 0.41m.

According to this result, by providing the partition plate 100 with the inclined support portion 102, the mixing region of the first molten steel 4a and the second molten steel 4b can be shortened. It was found that the effect of shortening the mixing zone can be further improved by adjusting the distance. Also, as in this verification example, for example, the length of the mixed region, that is, the length of the defective portion can be shortened, so the yield can be improved. A further potential advantage is the ability to reduce pre-cutting after slab analysis.

<Other embodiments>
According to the above-described embodiment, by providing the partition plate 100 with inclinations (supporting body portions 102) at both end portions of the main body portion 101, the mixing region can be shortened. This effect is due to the fact that the height direction position of the gap 11a has moved upward compared to the conventional art. In other words, the shape of the partition plate 100 is not limited to the above-described embodiment, as long as the height direction position of the gap 11a can be positioned above the bottom surface of the main body portion 101 .

For example, as shown in FIG. 10, the partition plate 200 may be configured to have a support portion 201 extending toward the short side wall 11 at the upper end of the vertical plate portion 103 extending vertically upward. By adopting such a shape, the gap 11a can be positioned above the bottom surface of the main body 101 as in the above-described embodiment, and the length of the mixing region can be shortened.

In this embodiment, the supporting body part 201 may be configured to have a V-shaped cross section perpendicular to the longitudinal direction, or may be configured in a circular shape or a flat plate shape. Moreover, the partition plate 200 may be configured to further have another support portion (not shown) extending from the main body portion 101 below the support portion 201 .

Further, according to the verification example described above, by adjusting the distance between the short side wall 11 and the other end portion 102b of the support portion 102, that is, the size of the gap 11a, it is possible to adjust the shortening of the mixing zone. Do you get it. For this reason, as shown in FIG. 11, the partition plate 300 may be configured such that an attachment portion 301 capable of adjusting the distance from the short side wall 11 can be connected to the tip of the support portion 102, for example. The attachment portion 301 is provided extending in the extending direction of the support portion 102 . Also, the shape of the attached portion 301 in a cross section perpendicular to the longitudinal direction is the same as that of the support portion 102, and is, for example, a V shape. By extending the attached portion 301 from the support portion 102, the length of the mixing region can be further shortened.

Further, for example, in a partition plate 400 as shown in FIGS. The shape of these support parts 401 and 402 can be designed arbitrarily. As shown in FIG. 12, the support 401 may have substantially the same shape as the support 102 of the above-described embodiment, ie, a shape inclined upward from the main body 101 . Alternatively, as shown in FIG. 13, the support 402 may have a horizontal portion 402a horizontally extending from the body portion 101 and an inclined portion 402b inclined upward from the horizontal portion 402a. Further, the shape of the cross section of the support members 401 and 402 perpendicular to the longitudinal direction may be V-shaped as in the illustrated example, or may be circular or flat.

Although the embodiments of the present invention have been described above, the present invention is not limited to such examples. It is obvious that a person skilled in the art can conceive various modifications or modifications within the scope of the technical idea described in the claims, and these are also within the technical scope of the present invention. be understood to belong to

INDUSTRIAL APPLICABILITY The present invention is useful when continuously casting molten steel of different steel grades.

1 Continuous Casting Equipment 2 Tundish 3 Mold 4a First Molten Steel 4b Second Molten Steel 5 Immersion Nozzle 6 Slab 7 Roll Group 8 Reduction Roll 10 Long Side Wall 10a Gap 11 Short Side Wall 11a Gap 20 Mounting Jig 21 Fixing Member 22 support member 23 hollow member 24 hook 30 solidified shell 31 inclusion 32 meniscus 33 molten powder 50 discharge port 100 partition plate 101 body portion 102 support portion 102a one end portion 102b other end portion 103 vertical plate portion 104 hanging shaft 105 hanging tool 200 Partition plate 201 Support body portion 300 Partition plate 301 Attachment portion 400 Partition plate 401, 402 Support body portion 402a Horizontal portion 402b Inclined portion

Claims (7)

A partition plate for continuous casting of different steel grades used in a mold when continuously casting molten steel of different steel grades,
a horizontally extending main body;
a plate-shaped support provided at both ends in the longitudinal direction of the main body;
a vertical plate portion extending vertically upward from the main body portion;
one end of the supporting body is connected to a longitudinal end of the main body;
the other end portion of the support portion is positioned above the bottom surface of the main body portion;
The support portion is provided so as to be inclined upward from a longitudinal end portion of the main body portion,
The inclination angle of the support from the horizontal direction is 30 to 60 degrees,
The support body displaces the maximum flow velocity point of the molten steel in the mold, which is the flow velocity of the molten steel flowing through the gap between the other end of the support body and the mold, above the bottom surface of the main body,
A partition plate for continuous casting of different steel grades, characterized by being smaller than the opening of the mold in plan view. 2. The partition plate for continuous casting of different steel grades according to claim 1, wherein the main body has a V-shaped cross section perpendicular to the longitudinal direction. 3. The partition plate for continuous casting of different steel grades according to claim 1 or 2 , wherein said support portion is detachably attached to said main body portion. The partition plate for continuous casting of different steel grades according to any one of claims 1 to 3 , characterized in that the main body is detachably suspended from the bottom of the tundish. The partition plate for continuous casting of different steel grades according to any one of claims 1 to 4, characterized in that the other end portion of the support portion is located 100 mm or more above the bottom surface of the main body portion. A partition plate for continuous casting of different steel grades used in a mold when continuously casting molten steel of different steel grades,
a horizontally extending main body;
a plate-shaped support provided at both ends in the longitudinal direction of the main body;
a vertical plate portion extending vertically upward from the main body portion;
one end of the support portion is connected to a side surface of the vertical plate portion ;
the other end of the supporting body is located 100 mm or more above the bottom surface of the main body,
The support body displaces the maximum flow velocity point of the molten steel in the mold, which is the flow velocity of the molten steel flowing through the gap between the other end of the support body and the mold, above the bottom surface of the main body,
A partition plate for continuous casting of different steel grades, characterized by being smaller than the opening of the mold in plan view. A method for continuous casting of different steel grades in which molten steels of different grades are continuously cast using the partition plate for continuous casting of different steel grades according to any one of claims 1 to 6 ,
pouring a first molten steel into the mold;
Then, a step of inserting the partition plate for continuous casting of different steel grades into the mold;
and then pouring a second molten steel into the mold.

Images