JP2621949B2 - Rear weir in single belt continuous casting machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rear weir capable of manufacturing thin cast slabs having different sheet widths by a single belt type continuous casting apparatus.

[Conventional technology]

Recently, a continuous casting method for directly producing a thin cast slab having a thickness of several mm to several tens mm close to the final shape from molten metal such as molten steel has attracted attention. According to this method, the hot-rolling step can be simplified or omitted, and the rolling for obtaining the final shape can be light, so that the steps and equipment can be simplified.

One of the continuous casting methods is a single belt method. FIG. 3 shows an apparatus proposed by the present inventors as Japanese Patent Application No. 60-155247. In this device, a metal belt 1 is stretched over a pair of pulleys 2a and 2b,
It runs as an endless track. By keeping one pulley 2a high, the endless track of the belt 1 rises toward the pulley 2a. A plurality of heat-resistant blocks 3 connected by a chain or the like are arranged around the belt 1, and these heat-resistant blocks 3 move in synchronization with the running of the belt 1.

The heat-resistant block 3 serves as a side weir 5 that partitions both sides of the pool 4 at the upper portion where the belt 1 travels linearly. On the other hand,
A rear weir 6 is provided upstream of the basin 4.
As a result, a basin 4 in which only the traveling direction of the belt 1 is opened is formed. The molten metal 8 is poured into the pool 4 from a pouring device 7.

The poured molten metal 8 is removed through the belt 1 by the cooling device 9 arranged on the back surface of the belt 1, cooled and solidified to form a solidified shell 10. The solidified shell 10 is transported rightward in FIG. 3 as the belt 1 travels. Since the heat removal continues during this transport process, the solidified shell 10
Grows into a thin cast slab 11 having a predetermined thickness, and is sent out from the basin 4. The cast slab 11 is then rolled to a target thickness by a pressure roll 12 and wound up by a winding device 13 as a thin coil 14.

The width of the thin cast slab 11 manufactured by this method is regulated by the mutual interval between the pair of side weirs 5. At this time, since the rear weir 6 is disposed between the side weirs 5, if the interval between the side weirs 5 is changed to manufacture thin cast slabs 11 having different plate widths, the rear weir 6 is changed to the plate after the change. It was replaced with the one corresponding to the width, and the work of adjusting the interval between the side weirs 5 was performed. Therefore, the work of changing the plate width is troublesome and time-consuming, and reduces the operation efficiency of the apparatus.

Therefore, the present inventors have developed a device using a rotary rear weir to easily change the plate width, and filed an application as Japanese Patent Application No. 62-257907.

FIG. 4 shows a state in which the board width is changed using the rotary rear weir. When manufacturing the thin cast slab 11 having the maximum plate width, the rear weir 6 is arranged parallel to the width direction of the belt 1 as shown by a solid line. At this time, the surface of the basin 4 is partitioned by A ₁ B ₁ C ₁ D ₁ . On the other hand, when manufacturing a thin cast slab 11 having a small width, the rear weir 6 is rotated as shown by a dashed line to form a pool 4 having a bath surface sectioned by A ₂ B ₂ C ₂ D _2. . In this case, different from the distance A ₂ -D ₂ and the distance B ₂ -C _2, the thickness of the solidified shell 10 to grow on the surface of the belt 1 can vary in the width direction. Then, if necessary, the belt 1 is inclined in the width direction, and the distance A ₂ -D ₃ and the distance B ₂ -C ₃
By forming the pool section 4 having the molten metal surface A ₂ B ₂ C ₃ D ₃ having the same value as above, it is possible to manufacture the thin cast slab 11 having no wall thickness variation.

[Problems to be solved by the invention]

As described above, when the width of the pool portion 4 is changed by rotating the rear weir 6, the thin cast slab 11 having no thickness variation in the width direction.
In order to manufacture the device, a device for inclining the belt 1 in the width direction is required, and the equipment becomes complicated accordingly.
In addition, when the rear weir 6 is rotated at a large angle in order to produce the thin cast slab 11 having a small plate width, it is required that the inclination angle in the width direction of the belt 1 is also increased, and the pool portion 4 becomes unstable. . Further, a gap is formed between the side weir 5 and the rear weir 6 in the vicinity of both side edges 6a and 6b of the rear weir 6, and a defect for the intrusion and solidification of the molten metal into the gap is caused by the thin cast slab 11.
At both ends.

In view of this, the present invention makes the length of the rear weir itself in the belt width direction variable, always maintains the rear weir at a right angle to the side weir, and does not need to incline the belt in the width direction. It is an object of the present invention to provide a rear weir capable of forming a reservoir.

[Means for solving the problem]

In order to achieve the object, the rear weir of the present invention is a single-belt continuous belt for manufacturing thin cast slabs by cooling and solidifying molten metal injected into a pool provided on a running metal belt. In the casting apparatus, a rear weir partitioning an upstream side of the pool is constituted by a plurality of members, and these members are slidably arranged in the width direction of the metal belt.

〔Example〕

FIG. 1 shows an example in which the rear weir 6 is divided into two parts and the parts are slid together.

The basin 4 in this embodiment has side dams 5a and 5 on both sides.
At b, the upstream side is formed on the belt 1 partitioned by the rear weir 6. The rear weir 6 is composed of divided pieces superimposed on each other.
6a and 6b are slidably arranged in the width direction of the belt 1.
When the split piece 6b is slid relative to the split piece 6a as shown by the arrow, the rear weir 6 in the width direction of the belt 1 is moved.
Is changed. Therefore, by moving the side weirs 5a and 5b close to and away from each other in accordance with the length, the width of the pool portion 4 is changed according to the target plate width of the thin cast slab to be manufactured.

As the divided pieces 6a and 6b, a material having excellent heat resistance such as alumina, silica, zirconia, and alumina graphite is used. When the surfaces of the divided pieces 6a and 6b are finished smoothly and they are brought into close contact with each other, it is possible to prevent molten metal from entering the pool portion 4 between the divided pieces 6a and 6b. Also, when a coating of alumina, zirconia, boron nitride or the like having excellent heat resistance, wear resistance and lubricity is applied to the surfaces of the divided pieces 6a and 6b, the sliding between the divided pieces 6a and 6b is smoothly performed.

It is preferable that the tip 15 of the divided piece 6b arranged on the side of the basin 4 is processed into a knife edge shape. This tip 15
Is pressed against the surface of the divided piece 6a under the pressure of the molten metal from the basin 4. Therefore, when sliding, generation of a gap between the divided pieces 6a and 6b is suppressed.

As described above, the relative sliding of the divided piece 6b with respect to the divided piece 6a is performed in the width direction of the belt 1, that is, the side dams 5a and 5b.
Along a direction perpendicular to Therefore, the rear weir 6 are always side weirs 5a, perpendicular to 5b, the distance A ₂ -D ₂ and the distance B ₂ -C ₂ and no to be different as explained in Figure 4,
There is no need to tilt the belt 1 in the width direction. Therefore, the side weirs 5a, 5b correspond to the sliding of the divided pieces 6a, 6b.
The basin portion 4 having a predetermined width is formed simply by moving the nozzles close to and away from each other. For example, compared to the case where the split pieces 6a and 6b are opened to the maximum, by maximizing the overlap of the split pieces 6a and 6b,
The width of the basin 4 can be reduced to almost half. The approach and separation of the side weirs 5a and 5b are partially
Either a method in which a and 5b are moved in the width direction of the belt 1 or a method in which they are moved as a whole can be adopted.

FIG. 2 shows an example in which the rear weir 6 is divided into three parts. In this embodiment, the split pieces 6 are provided on both sides of the split piece 6c located at the center.
d and 6e are arranged. In this case, the divided piece 6c is fixed, and the divided pieces 6d and 6e at both ends are slid in the direction of the arrow. As a result, the width of the basin 4 can be changed. Further, by designing the belt 1 on both sides in the width direction in such a manner that the divided pieces 6d and 6e are arranged under the same conditions, the both side edges of the cast thin-walled cast piece 11 have the same properties. Become.

The case where the thin cast pieces 11 having different plate widths are cast while changing the width of the well portion 4 has been described above. A change in the thickness of the thin cast slab 11 can be combined with the change in the plate width. For example, by changing the angle of inclination of the belt 1 with respect to the running direction, the length of the pool portion 4 is adjusted to control the growth of the solidified shell, and the thickness of the thin cast slab 11 carried out matches the target thickness. Let it. By combining the adjustment of the sheet width and the sheet thickness, it becomes possible to manufacture thin cast pieces 11 of various sizes according to demand with one continuous casting machine.

〔The invention's effect〕

As described above, in the present invention, the rear weir has a divided structure, and the length of the rear weir in the belt width direction is changed by sliding the divided pieces together.
Therefore, even when the width of the basin is changed, the rear weir is always maintained at a right angle to the side weir, and the molten metal surface shape of the basin is stabilized. As described above, according to the present invention, a pool portion having a width corresponding to a target plate thickness of a thin cast slab can be obtained by a simple operation, so that thin cast slabs of various sizes can be manufactured by one continuous casting machine. Becomes possible,
The operating efficiency of the equipment is improved.

[Brief description of the drawings]

FIG. 1 is a view for explaining a state in which a thin-walled slab is being cast using a rear weir divided into two parts, and FIG. 2 is a view illustrating a state in which a thin-walled slab is cast using a rear weir divided into three parts. It is a figure explaining a state. On the other hand, FIGS. 3 and 4 show a single-belt type continuous casting apparatus proposed by the present inventors. 1: belt, 2a, 2b: pulley, 3: heat-resistant block 4: pool, 5.5a, 5b: side weir, 6: rear weir 6a-6e: split piece, 7: pouring device, 8: molten metal 9: Cooling device, 10: Solidified shell, 11: Thin cast slab 12: Pressure roll, 13: Winding device, 14: Thin coil 15: Tip of split piece

Claims (1)

(57) [Claims] 1. A single-belt continuous casting apparatus for producing thin cast slabs by cooling and solidifying molten metal injected into a basin provided on a running metal belt. A rear weir in a single-belt type continuous casting apparatus, wherein a rear weir partitioning an upstream side is constituted by a plurality of members, and these members are slidably arranged in the width direction of the metal belt.