JPH0631403A - Continuous casting mold - Google Patents

Abstract

PURPOSE:To uniformly deprive heat from a solidified shell by arranging a partition wall plate for dividing a cooling chamber into two in the radius direction and forming multiple number of through-holes, from which plugs can be attached/detached to/from the wall part in the partition wall plate. CONSTITUTION:The partition wall 7 is arranged in the cooling chamber 8 outside of the inner wall 2 of a mold and the cooling chamber 8 is vertically divided into two by a flange 6. In the partition wall 7, the multiple number of the screw holes 10 penetrated so as to match to the plug 9 are arranged. Cooling water flows into the lower part of the cooling chamber 8 from an introducing hole 17 and then into a cooling water flowing passage 15 from the screw holes 10 in the partition wall 7 and the lower end of the partition wall 7, and ascends while cooling the inner wall 2 of the mold and come to a drainage hole 18. By screwing the plugs 9 into the screw holes 10 in the partition wall 7, the flow rate in the cooling water flowing passage 15 can partially be controlled and made to cope with the change of conditions, such as kind of steel, casting speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous casting mold (hereinafter also referred to as a mold). More specifically, the heat removal from molten steel in the mold during continuous casting is controlled to traverse the slab in the mold. The present invention relates to a continuous casting mold that can uniformly form a solidified shell on a surface.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, a continuous casting mold 21 has a mold inner wall formed of a copper plate having a good heat transfer coefficient.
A cooling water flow path 23 is formed on the back surface of 22 so that the cooling water flows from bottom to top. And in continuous casting,
Molten steel is poured into the mold 21 from a tundish (not shown) through a dipping nozzle 24 or directly, and the poured molten steel is cooled by a mold inner wall 22 to form a solidified shell, and the inside of the mold 21 is also cooled. Is further drawn in the process of being drawn downward, the solidified shell is grown to have a predetermined thickness, and then drawn under the mold 21.

By the way, the inner wall 22 of the mold during continuous casting
Is known to have the largest heat load in the vicinity of the meniscus where the molten steel is poured, and to decrease as the solidified shell grows below the meniscus. On the other hand, conventionally, the cooling of the back surface of the mold inner wall 22 is performed by flowing a cooling water with a substantially uniform amount of water from the bottom to the top, and it can be said that cooling of the mold inner wall 22 near the meniscus where the heat load is large is not always sufficient. Instead, the mold inner wall 22 may be deformed. When the mold inner wall 22 is deformed, the gap between the surface of the mold inner wall 22 and the solidified shell becomes non-uniform, so that the thickness of the molten slag that also serves as lubrication and flows into this gap becomes non-uniform, and the heat removal from the solidified shell occurs. Becomes uneven and the thickness of the solidified shell becomes uneven,
This may cause internal cracking of the slab, breakout during casting, and various troubles.

In order to solve the above-mentioned problems, a mold having a structure in which a cooling chamber is formed on the back surface of the inner wall of the mold and a cooling water injection nozzle is arranged in the cooling chamber, and disclosed in JP-A-3-42144. As described above, a vertical cooling water passage formed on the back surface of the inner wall of the mold is formed so that the vicinity of the meniscus is narrow and wide below it, and a mold having improved cooling capacity near the meniscus is proposed. .

[0005]

By the way, the above-mentioned molds are all excellent in that they can improve the cooling ability in the vicinity of the meniscus, but the former has never been equipped with a conventional mold. The structure of the cooling water injection nozzle is complicated because it is installed in the cooling chamber, and when nozzle clogging occurs and nozzle clogging occurs, there is a high risk that hot spots will occur and the same problems as in the conventional mold described above will occur. Become. On the other hand, the latter is uneconomical because the shape of the cooling water flow path is fixed, and it is not possible to deal with it when conditions such as steel type and casting speed are changed, and the number of molds held increases.

The present invention has been made in view of the above circumstances, and an object thereof is to improve the cooling ability in the vicinity of the meniscus and to uniformly remove heat from the solidified shell with a relatively simple structure. It is to provide a continuous casting mold which can be made and can cope with changes in conditions such as steel type and casting speed.

[0007]

In order to achieve the above object, the continuous casting mold of the present invention is a continuous casting mold in which a cooling chamber is formed on the back surface of the inner wall of the mold. A partition plate that divides the cooling chamber into two parts in the radial direction is provided at a distance, and a shielding plate that divides the cooling chamber on the back side of the partition plate into two parts is provided, and a plug can be attached to and detached from the wall part of the partition plate. A large number of through holes are formed.

[0008]

In the above mold of the present invention, since the through hole is formed in the partition plate, the cooling water passage formed between the back surface of the inner wall of the mold and the partition plate has a through hole from behind the partition plate. The flow of cooling water flows in, and the amount of inflow becomes maximum and the flow velocity becomes faster at the portion corresponding to the mounting position of the shield plate, so that the amount of heat removed increases and the cooling capacity can be improved. Further, since the plug is formed so that the through hole of the partition plate can be attached and removed, the inflow amount of the cooling water can be controlled by attaching the plug to the through hole of the predetermined portion, and the solidified shell formed in the mold can be made uniform. In addition to being able to control the thickness, it is possible to easily respond to changes in conditions such as steel type and casting speed.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a vertical sectional view of a continuous casting mold according to the present invention, and FIG. 2 is a sectional view taken along line XX of FIG.

In the figure, reference numeral 1 denotes a tubular frame for supporting a tubular mold inner wall (for example, a copper tube) 2 forming a casting surface. The tubular frame is provided with flange portions 3 and 4 at its upper and lower ends. A flange 6 for fixing the frame 1 itself to a mold vibrating device body (not shown) is provided at a predetermined position of the portion 5. The flange 6 projects in and out of the tubular portion 5 of the frame 1, and a quadrangular tubular partition 7 extending coaxially with the tubular portion 5 is fixed around the inside thereof. A cooling chamber 8 is formed between the partition wall 7 and the tubular portion 5, and the cooling chamber 8 is divided into upper and lower parts by a flange 6. Further, in the partition wall 7 below the mounting position of the flange 6, a female screw hole which penetrates in accordance with the male screw of the plug 9 is formed.
10 are drilled.

The inner wall 2 of the mold, like the partition wall 7, has a rectangular tubular shape and is housed in the cylinder of the frame 1, and flanges 11 and 12 are fixed around the upper and lower ends thereof, and a joint portion between them is formed. The sealing rings 13, 14 are fitted.
Further, a cooling water flow path 15 is formed in the vertical direction between the mold inner wall 2 and the partition wall 7. The flanges 11 and 12 are in sliding contact with the upper and lower surfaces of the upper and lower flange portions 3 and 4 of the frame 1, respectively, and are fixed to them with bolts 16 and 16 ---.

Reference numeral 17 denotes an inlet for cooling water which is partitioned by the flange 6, and is opened at a lower portion of the cooling chamber 8 which is also partitioned by the flange 6. Further, reference numeral 18 denotes a cooling water discharge port partitioned by the flange 6, which is opened at an upper portion of the cooling chamber 8 similarly partitioned by the flange 6.

Since the mold according to the present invention is constructed as described above, the cooling water during the continuous casting is introduced from the introduction port 17 into the lower part of the cooling chamber 8 defined by the flange 6, and then the partition wall 7. While flowing into the cooling water channel 15 from the female screw hole 10 and the lower end of the partition wall 7, the cooling water channel 15 rises while cooling the inner wall 2 of the mold, and is divided by the flange 6 from the upper part of the cooling water channel 15. It is guided to the upper part of the cooling chamber 8 and flows to reach the discharge port 18. In this flow, since there is cooling water flowing into the cooling water flow passage 15 from the female screw hole 10 of the partition wall 7, the flow rate in the cooling water flow passage 15 increases toward the upper position close to the mounting position of the flange 6, and as a result, the casting The cooling capacity at the position of the molten steel meniscus is improved, and the mold inner wall 2
The deformation due to the heat load can be prevented, and the heat removal from the solidified shell can be made uniform. Further, by screwing the plug 9 into the female screw hole 10 of the partition wall 7, the flow rate in the cooling water flow path 15 can be easily controlled, and it is possible to deal with a change in conditions such as steel grade and casting speed.

In the above embodiment, an example in which the female screw hole 10 is formed only in the lower portion of the partition wall 7 has been described, but the present invention is not limited to this example, and in particular the molten steel meniscus at the upper portion. The female screw hole 10 may be provided above the position. In this case, the cooling ability above the position of the molten steel meniscus can be adjusted and troubles such as solidification of the molten slag can be prevented.

[0015]

As described above, in the continuous casting mold according to the present invention, the cooling water between the inner wall of the mold and the partition plate has a simple structure in which the partition plate is provided with the plug hole. It is possible to control the flow rate, which can absorb the heat load from the molten steel meniscus to the inner wall of the mold during casting and prevent the inner wall of the mold from being deformed. As a result, the thickness of the solidified shell becomes uniform, and it is possible to prevent various problems such as internal cracking of the slab and further breakout during casting. further,
It is possible to easily cope with changes in conditions such as steel type and casting speed.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a continuous casting mold according to the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a vertical cross-sectional explanatory view of a conventional continuous casting mold.

[Explanation of symbols]

1: Cylindrical frame 2: Mold inner wall
3, 4: Flange part 5: Cylindrical part 6: Flange
7: Partition wall 8: Cooling chamber 9: Plug 1
0: Female screw hole 11, 12: Flange 13, 14: Sealing ring 15: Cooling water flow path 16: Bolt 1
7: Inlet port 18: Outlet port

Claims (1)

[Claims] 1. A continuous casting mold in which a cooling chamber is formed on the back surface of the inner wall of the mold, and a partition plate which divides the cooling chamber into two parts in the radial direction at a distance from the inner wall of the mold in the cooling chamber. A continuous casting mold characterized in that a shielding plate that divides the cooling chamber on the back side of the partition into two parts is provided, and a large number of through holes through which plugs can be attached and detached are formed in the wall portion of the partition plate.