JP2006239731A - Partition implement used during connection of different kinds of steel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a partition implement used during the connection of different kinds of steel which, even when used for a vertical bending type continuous casting machine, has no possibility of steel leakage at a straightening point, further when dropped to a mold, is guided by a solidified shell and is inserted therein in a fixed direction, and provides remarkably improved rate of success by the formation of cavities. <P>SOLUTION: The partition implement is constituted in such a way that the inside of each angle steel 3 is longitudinally provided with a support 4, and angle steels 5 with the same cross-sectional shape are heaped on each angle steel 3 between the supports 4, and each support 4 is horizontally provided with a horizontal bar 6 caught in each solidified shell 7 and performing the positioning of insertion quantity. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a partitioning jig used for the purpose of reducing the mixing of hot water of different steel types in continuous casting of steel, and provided at the lower end of the support column and the support column, and stacked vertically on a plurality of sheets. And V-shaped steel material.

  In continuous casting of steel, when different steel types are continuously cast, a mixing jig is put into a mold to reduce the mixing of molten steel of the front and rear steel types.

Conventionally, H-shaped steel has been used as the partitioning jig, but the following Patent Document 1 discloses one made of a V-shaped steel material 11 as shown in FIG.
JP 2004-174515 A

  The H-section steel can partition different steel types with a high probability with the strength of the section steel itself. However, when used in a vertical bending type continuous casting machine, the H-section steel has a correction point where bending stress is applied. However, there was a risk of breaking the solidified slab and leaking steel from the fracture.

  For V-shaped steel, there is no risk of steel leakage at the correction point, and when the partition jig is dropped, it is guided by the solidified shell and can be inserted into the molten steel in a certain direction. The upper part of the slab where solidification has started is connected to the rear steel grade, so that when the oxygen is blown to prevent solidification or the next molten steel is injected, the partition jig melts, and the lower part of the partition jig However, there was a problem that the success rate of the different steel type partition that succeeded by forming a cavity was low.

  The above-mentioned cavity is formed by rapidly cooling and solidifying the molten steel in the mold by dropping the partitioning jig into the mold, and the formation of the cavity means that there is no mixing of different steel types. Is confirmed by cutting the slab of the connecting portion after connecting different steel types.

  In the present invention, a partition jig made of a V-shaped steel material is improved so that different steel types can be partitioned with a high success rate.

  The invention according to claim 1 is a partitioning jig used for the purpose of reducing hot water mixing of different steel types when carrying out connection of different steel types in continuous casting of steel, and is provided at a support column and a lower end of the support column. It is characterized by comprising a plurality of V-shaped steel members stacked one above the other.

  Here, the V-shaped steel materials may have different cross-sectional shapes, but preferably have the same cross-sectional shape. Each V-shaped steel material may be simply stacked, but is preferably integrally connected by, for example, welding or bolts.

  The width of the V-shaped steel material is preferably about 85 to 92% of the mold width. When the width of the V-shaped steel exceeds 92% of the mold width, the V-shaped steel interferes with the solidified shell and cannot be inserted. When the width of the V-shaped steel is less than 85%, the molten steel of the rear steel type is in contact with the solidified portion of the slab and the V-shaped steel. It enters from between the steel and mixes with the unsolidified part of the previous steel type.

  The thickness of the V-shaped steel material is preferably about 62 to 66% of the mold thickness. When the thickness of the V-shaped steel exceeds 66% of the mold thickness, the V-shaped steel interferes with the solidified shell and cannot be inserted. When the thickness of the V-shaped steel is less than 62%, the molten steel of the rear steel type becomes the solidified portion of the slab and the V-shaped steel. It enters from between the steel and mixes with the unsolidified part of the previous steel type.

  Therefore, the invention according to claim 2 is characterized in that, in the invention according to claim 1, the width of the V-shaped steel material is 85 to 92% of the mold width and the thickness is 62 to 66% of the mold thickness.

  The invention according to claim 3 is the invention according to claim 1 or 2, in which the horizontal bar that is hooked on the solidified shell when the partition jig is dropped to prevent further insertion of the partition jig and restricts the insertion amount is attached to the support column. It is provided.

  In the present invention, the mounting position of the horizontal bar is 300 to 400 mm above the V-shaped steel material, preferably about 350 mm.

  According to the invention according to claim 1, even when used in a vertical bending type continuous casting machine, there is no risk of steel leakage at the correction point, and when the partition jig is dropped, the V-shaped steel material is guided to the solidified shell, In addition to the effect of being able to be inserted in a certain orientation, since there are a plurality of V-shaped steel materials, even if one part melts, if all does not melt, The molten steel around the shape steel material is quenched and a cavity is formed by solidification shrinkage. Therefore, the success rate of the different steel type partition can be significantly increased.

  According to the second aspect of the present invention, the V-shaped steel material can be inserted without interfering with the solidified shell, and the molten steel of the rear steel grade enters between the solidified portion of the slab and the V-shaped steel material, and the unsolidified portion of the front steel grade. Less likely to mix with

  If the partitioning jig is inserted shallowly, there is a possibility that the melting of the V-shaped steel material may proceed when oxygen is blown for connection with the subsequent steel type. The deep insertion of the V-shaped steel material interferes with the solidified shell, Although it is difficult to insert horizontally, the amount of hot water mixed increases and the yield decreases due to hot water mixing. However, as in the invention according to claim 3, the horizontal bar is solidified when a jig is inserted and a jig is inserted. If it is hooked on the shell so that no further insertion is possible, the partitioning jig can be positioned and inserted at an appropriate position.

Hereinafter, a partitioning jig according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a front view of a partition jig 1 according to the present invention, FIG. 2 shows a cross section taken along line AA of FIG. 1, and FIG. 3 shows a cross section taken along line BB of FIG. As the angle steel 2, steel pillars 4 are vertically provided by steel plates 3 on both sides of the angle steel 2, and the angle steel 2 between the pillars 4 has the same cross-sectional shape as the angle steel 2. Steel 5 is stacked and connected integrally with a bolt (not shown). In the illustrated example, two angle steels 2 and 5 are used, but three or more angle steels may be stacked and connected.

  A horizontal bar 6 made of copper is also provided on the column 4 at a height of 350 mm from the steel plate 3 and slightly shorter than the mold width. When the partitioning jig 1 is dropped into the mold, the horizontal bar 6 is hooked on the upper end of the solidified shell 7 shown in FIG. 1 to position the partitioning jig so that the partitioning jig 1 can be inserted into an appropriate position. ing.

Example 1
Using the partition jig 1 in which the width a of the partition jig 1 shown in FIG. 1 is 85 to 92% of the mold width and the thickness b of the partition jig 1 shown in FIG. 2 is 62 to 66% of the mold thickness, vertical bending is performed. FIG. 4 shows a connection between a low carbon steel having a carbon content of 0.006% and a medium carbon steel having a carbon content of 0.11 to 0.12% by dropping into the mold of a continuous casting machine of the mold. As described above, the carbon C value of the slab fluctuated in the range of 0.006% to 0.11 to 0.12% in the range of slab length of 2400 mm from the dissimilar steel joint, and the range of hot water mixing was 2400 mm in slab length. . Of the 276 connections, a cavity was formed under the partitioning jig after 262 times, and the success rate was 95%.

Comparative Example Using a conventional partitioning jig 11 shown in FIG. 5 and connecting low and medium carbon steel under the same conditions as in the example, the carbon C value was 0.006% in the range of 6800 mm from the joint of different steel types. From 0.11 to 0.12%, the hot water mixing range reaches 6800mm in slab length, and the formation of cavities is detected only once out of 17 connections, and the success rate is It was 6%.

  As described above, in the example, the range of hot water mixing was 2400 mm in slab length, whereas the range of hot water mixing in the comparative example was 6800 mm in slab length. In the example, compared to the comparative example, The range could be greatly reduced.

  Moreover, the success rate of the Example was 95%, and the success rate was significantly improved as compared with the comparative example of 6%.

  The partition jig according to the present invention is used when connecting different steel types in a continuous casting machine, particularly a vertical bending type continuous casting machine.

Front view of the partition jig according to the present invention AA line sectional view of FIG. BB sectional view of FIG. Graph showing range of hot water mixing Sectional view of a conventional partitioning jig

Explanation of symbols

1. ・ Partition jig 2,5 ・ ・ Angle 3 ・ ・ Steel 4 ・ ・ Post 6 ・ ・ Horizontal bar 7 ・ ・ Solidified shell

Claims (3)

  In continuous casting of steel, it is a partitioning jig used for the purpose of reducing the mixing of hot water of different steel types when connecting different steel types, and is provided at the lower end of the support column and the lower end of the support column, and is a V-shaped piled up and down A partitioning jig used when connecting different steel types, characterized by comprising a steel material.   The partition jig used for connecting different steel types according to claim 1, wherein the dimensions of the V-shaped steel material are 85 to 92% of the mold width and 62 to 66% of the mold thickness.   3. A heterogeneous steel type connection according to claim 1 or 2, wherein a horizontal bar is provided on the support column, which is hooked to the solidified shell when the partitioning jig is dropped to prevent further insertion of the partitioning jig and restricts the amount of insertion. A partitioning jig used sometimes.

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