JPH05253651A - Method for casting clad steel sheet by twin roll type continuous casting - Google Patents

Abstract

PURPOSE:To provide a casting method for producing a clad steel sheet having a high accuracy by giving oscillation in the vertical direction and stably casting in a twin roll type continuous casting. CONSTITUTION:By perpendicularly inserting a parting plate into a molten metal pouring basin part formed between the rolls 1 and side weirs 2, the molten metal pouring basin part is divided into two parts, such as 3a, 3b and also, the side weirs 2 and the parting plate 4 are integrated, and at the time of casting by pouring the different kinds of the molten metals into each molten metal pouring basin part, by giving the oscillation in the perpendicular direction to the integrative side weir 2 and the parting plate 4, so as to satisfy 5 <= frequency (1/sec) X amplitude (mm) <=100(mm/sec), the clad steel sheet is cast. By this method, mixing of the molten metals and the stickness of the metal between mutual molten metal pouring basin parts are prevented and further, splash and waving of the molten metal surface are prevented and the solidified starting point position is kept constant and the clad steel sheet having the accurate thickness can be produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting method for continuously producing a clad steel plate by injecting different kinds of molten metals by twin roll type continuous casting for producing a thin plate slab.

[0002]

2. Description of the Related Art A method for casting a thin plate slab by twin rolls is
Known as the Bessemer method, this casting method is, for example, as shown in FIG. 2, side weirs 12 are attached to opposite side surfaces of the upper part of the roll 11, and a molten metal pool 13 is formed between the side dam 12. Form.

The molten steel injected from the pouring nozzle 14 into the basin 13 is cooled from the solidification start point 15 in contact with the roll 11 to start solidification to form a shell 16 and roll kiss points 17 at both ends. The solidified shell 16 formed on the roll surface is integrated and drawn downward to form a cast piece 18.

A method of casting a clad steel plate with twin rolls is, for example, as disclosed in Japanese Patent Laid-Open No. 4-9251, two rolls 21 and a roll 21 as shown in FIGS. 3 (a) and 3 (b). The side dams 22 provided on both side surfaces form a basin 23, and a partition plate 24 is vertically inserted between the side basins to divide the basin into right and left like 23a and 23b.

Next, different molten metals are injected from the injection nozzles 25a and 25b into the divided pools 23a and 23b, respectively, and solidification shells 27a and 2b from the solidification start points 26a and 26b contacting the rolls 21 in the pools respectively.
7b is formed.

The solidified shells 27a and 27b are integrated at the roll kiss point 28 and are drawn downward to form a clad slab 29 in which different kinds of molten metals are superposed.

In this case, depending on the type of molten metal, a large amount of slag or metal adheres to the side dam 22 depending on the wettability. Therefore, in the process of forming the solidified shells in the pools 23a, 23b, the solidified shells 27a, 2
An imbalance such as thickness occurs between 7b. Therefore, the side dam 22 is normally subjected to lateral vibration to prevent slag and metal from adhering.

[0008]

In the conventional method for casting a clad steel plate, the side dam 22 and the partition plate 24 are not fixed to each other in order to give lateral vibration to the side dam 22. Both hot water pools 23
The molten metals a and 23b are mixed.

The present invention has been made in view of the above problems,
Provided is a twin roll casting method for a clad steel plate by a twin roll type continuous casting to obtain a highly accurate clad steel by stable casting.

[0010]

According to the present invention, a hot water pool is formed by two rolls and side weirs provided on both side surfaces of the roll, and a partition plate is inserted vertically between the side weirs to form a hot water pool. In a method for casting a clad steel plate in which parts are divided and different molten metals are respectively injected into the divided pools, the side dam and the partition plate are integrated, and the integrated side dam and partition plate have the following formula 2 Is a method of casting a clad steel plate by twin roll type continuous casting, characterized in that the casting is performed while applying vibration in the vertical direction so as to satisfy the above condition.

[0011]

[Equation 2] 5 ≦ f · a ≦ 100 (mm / sec) (2) where f: frequency (1 / sec) a: amplitude (mm)

[0012]

According to the present invention, the partition plate inserted between the side dams is integrated with the side dams to prevent the molten metal from mixing in the divided pools, and the integrated side dams and the partition plates are perpendicular to each other. Providing vibration in the direction prevents slag and ingots from adhering and prevents splashes and ripples on the surface of the molten metal due to the partition plate, keeps the surface of the molten metal stable and keeps the clad of the correct thickness. It forms a steel plate.

Here, f × given to the side weir and the partition plate
The reason that the value of a is 5 to 100 (mm / sec) is to keep the relative velocity with the molten metal due to vibration at this value, and the values of f and a are different depending on the volume and size of the pool. Select a value.

If f × a is less than 5, the effect of preventing the adhesion of slag and metal is not sufficient, and if it exceeds 100, the side weir and the partition plate are mechanically unreasonable, and the adhesion is further prevented. Can not be expected to be effective. Therefore, 5 ≦ f · a ≦
It was set to 100 (mm / sec).

[0015]

FIG. 1 is a drawing showing an example of a twin roll type continuous casting apparatus for producing a clad steel plate suitable for carrying out the present invention. FIG. 1 (a) is a side view and FIG. 1 (b) is a drawing. It is a top view.

In this continuous casting apparatus, a molten metal pool 3 is formed by two rolls 1 and side dams 2 provided on both side surfaces of the rolls, and a partition plate 4 is vertically inserted between the side dams to pool the molten metal. The part is divided into left and right like 3a and 3b.

The side dam 2 and the partition plate 4 are integrated so that the molten metal injected between the pools 3a and 3b does not flow in the range of the depth where the partition plate 4 is inserted. There is.

Next, different molten metals are injected from the injection nozzles 5a and 5b into the divided pools 3a and 3b, respectively. To form.

The solidified shells 7a and 7b are integrated at the roll kiss point 8 and are pulled out downward to form a clad slab 9 in which different kinds of molten metals are superposed.

During this time, the side dam 2 and the partition plate 4 are integrated.
Gives a vibration in the vertical direction under the condition of the frequency and the amplitude shown in the above-mentioned equation 2.

By vibrating in the direction perpendicular to the molten metal surface in this way, it is possible to prevent the slag and the metal from adhering to the side dam 2 and the partition plate 4, and also to prevent the molten metal surface from splashing and waviness. And the stability of the surface of the bath can be maintained.

[0022]

As described above, according to the present invention, the side dam and the partition plate are integrated with each other, and the integrated side dam and the partition plate are vertically vibrated to melt each other between the pools. Prevents metal from mixing, prevents slag and ingots from adhering, and prevents splashes and ripples on the molten metal surface. A thick clad steel plate can be manufactured.

[Brief description of drawings]

FIG. 1 is a drawing showing an example of a twin-roll type continuous casting apparatus for producing a clad steel sheet suitable for carrying out the present invention,
1A is a side view and FIG. 1B is a plan view.

FIG. 2 is a side view showing an example of a conventional twin roll type continuous casting apparatus for producing a general thin plate cast piece.

FIG. 3 is a drawing showing an example of a twin-roll type continuous casting apparatus for producing a conventional clad steel plate, FIG. 3 (a) is a side view, and FIG. 3 (b) is a plan view.

[Explanation of symbols]

 1 Casting roll 2 Side weirs 3a, 3b Hot water pool 4 Partition plates 5a, 3b Injection nozzles 6a, 3b Solidification start point 7a, 7b Solidification shell 8 Roll kiss point 9 Cast piece

Claims (1)

[Claims] 1. A hot water pool portion is formed by two rolls and side weirs provided on both side surfaces of the roll, and a partition plate is vertically inserted between the side weirs to divide the hot water pool portion. In a method for casting a clad steel plate in which different kinds of molten metals are injected into the pool, the side dam and the partition plate are integrated, and the integrated side dam and the partition plate are vertically aligned so that the following formula 1 is satisfied. A method for casting a clad steel plate by twin roll type continuous casting, which is characterized in that the casting is performed while applying vibration. [Formula 1] 5 ≦ f · a ≦ 100 (mm / sec) (1) However, f: Frequency (1 / sec) a: Amplitude (mm)