JPS61212452A - Twin drum type continuous casting machine - Google Patents

Abstract

PURPOSE:To eliminate the protrusion of a solidified shell to the outside and to improve the sliding life of side dams by forming the end parts of drum bodies to have the diameter smaller than the diameter in the central part of the drums. CONSTITUTION:A molten metal is poured between the two drums 1, 15 and the side dams 20 and when the molten metal is cooled, the solidified shells are formed on the drum surfaces. The two solidified shells 30, 31 are press welded when the shells arrive at the narrowest space part on rotation of the twin drums 1, 15. Tapered recesses 50 are provided at the drum ends and therefore the shells 30, 31 are not strongly compressed at the ends of the drum bodies and are prevented from projecting laterally. The side pressure against the side dams is consequently slight and the generation of the sliding wear of the dams is prevented. The life of the side dams is extended and the operation of the twin drum type continuous casting is stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention provides a method for pooling molten metal between two rotating drums,
This is cooled while rotating the drum to continuously form a thin plate t.
- Concerning a twin-drum continuous casting machine for g-casting.

[Background of the invention]

Generally speaking, twin drum type continuous casting machines are
As seen in the publication, the molten metal is pooled between two drums, the molten metal is cooled and solidified on the surfaces of the two drums, and the two drums are then driven to rotate to press the two solidified shells together to form a thin plate. This is a continuous manufacturing device.

In the thin plate manufacturing method using such an apparatus, as pointed out in the above-mentioned publication, solidification inevitably progresses more easily at the width edges of the plate than at the center of the plate.

- 10,000, Solidified shells 30, 31f generated on the two drums 1.15 shown in FIG. 5: At the narrowest inter-drum crimping portion 12 to be crimped, a pressure P for crimping the solidified shells is generated. When the solidified shell is pressed in this manner, a pressure P is generated on the surface of the drum, but at the same time, pressure Pa is also generated in the lateral and vertical directions as shown in FIG.

Pυ occurs. That is, the material compressed by the drum tries to escape laterally and vertically, creating pressure in each direction as described above.

FIG. 4 is a vertical cross-sectional view of the center shown in FIG. A force acts to open outward at Ps. As shown in the above-mentioned publication, this force becomes correspondingly large when solidification progresses excessively at the width edges of the plate.

Generally, when manufacturing 1 ft of steel material, the temperature of the molten metal is 1
The temperature is extremely high, such as 500C, and the side dam (Fig. 4) is made of refractory bricks that can withstand such high temperatures.

However, since the temperature of the solidified steel is close to 1350 to 1400C, the pressure P1 generated in the crimping part 12 that crimps the solidified steel is equal to the deformation resistance of the high temperature steel material, and is a large pressure of about 200 to 100 d/d. has.

On the other hand, the side dam 20 described above and shown in FIG.
Since it is made of refractory bricks, its strength is extremely low at high temperatures as described above, and as the thin plate 19 is pulled downward due to the pressure Pg shown in Figure 4, it rapidly wears out and the double drum This prevents continuous casting from being put to practical use on an industrial scale.

Further, the side dam 20 shown in FIG. 4 is fixedly disposed from the outside and is slidably attached to the rotating drums 1 and 15 (not shown). Therefore, if the mounting force of the side dam 20 is weak, the mounting force of the side dam 20 will be defeated by the pressure P- shown in the same figure, and the side dam 20 will retreat outward, causing an accident of leakage and moving to the side of the solidified shell. Protrusion occurs.

As a means of solving the above problems, in the example of the above publication,
It has been proposed that both ends of the drum's outer peripheral surface be made of a material with low thermal conductivity. In areas with low thermal conductivity, the thickness of the solidified shell formed is thin, so even if the refractories are crimped, the pressure will be lower than that of the other central parts, resulting in the effect of extending the life of the side refractories. It is assumed that. however,
Even with such means, it is difficult to effectively solve all of the above problems.

[Purpose of the invention]

In view of these circumstances, the present invention has developed a twin drum crimping part that eliminates the protrusion of the solidified shell to the outside, significantly improves the sliding life of the side dam, and enables stable casting. The purpose is to provide a drum type continuous casting machine.

[Summary of the invention]

In order to achieve the above object, the present invention provides a drum for a twin-drum continuous casting machine, in which the diameter of the drum surface that forms the solidified shell and faces the widthwise end of the slab is adjusted to the center of the drum. This is applied to at least one of the station drums.

By configuring the diameter of the drum surface in this way, even if the solidified shell formed on the surfaces of the two drums is crimped and rolled at the narrowest part of the twin drums, the reduction rate at the end of the drum can be around zero. Therefore, no protrusion occurs due to lateral pressure bonding of the solidified shell,
Therefore, the lateral pressure on the side dam is small, and it is possible to prevent the dam from sliding.

The present invention will be explained in detail below based on illustrated embodiments.

[Embodiments of the invention]

FIG. 1 is a schematic view of the twin-drum continuous casting machine of this embodiment seen from above, and FIGS. 2 and 3 show the state of crimping of the solidified shell.

The drum shape, an example of which is shown in FIG. 1, has tapered recesses 5o at both ends of the drum 1.degree. 150 mm.

First, molten metal is poured between the two drums 1 and 15 and the side dam 2°, and when it is cooled, a solidified shell is formed on the drum surface. Such a solidified shell will be in the state shown in FIG. 2 just before the twin drums 1, 15 are rotated and reach the narrowest armpit. That is, each drum 1.15 has a solidified shell 30.
．． 31 is attached, and the molten metal 2 is interposed between them.

However, as the rotation progresses further and reaches the narrowest gap between the twin drums, the two solidified shells 30 and 31 are pressed together, as shown in Figure M3.

In this way, in the present invention, the tapered recess 5 is provided at the end of the drum.
0, the solidified shell 30 is formed at the end of the drum body.
, 31 are not strongly compressed and can be prevented from protruding in any direction.

That is, depending on the selection of the amount of the tapered recess 50 at the end of the drum body shown in FIG.
As shown in the figure, it is possible to create a slight gap 51. Figure 1 shows an example in which a tapered recess 5o is provided at the end of the drum. Since it is sufficient that the diameter is smaller than the diameter at the center of the drum, the shape of the drum may be as shown in FIG. The effects of the present invention can be fully obtained.

Also, as shown in FIG. 7, the effects of the present invention can be obtained even with the drum 56 having a gentle convex curve.

In addition, although FIG. 1 shows a case in which each of the two drums has a tapered recess at the body end, the tapered recess is, of course,
It may be provided on the side of one drum in the twin rolls, and the other drums may be of a thousand rows.

Furthermore, if the present invention is used in combination with a twin-drum continuous casting machine that uses a devised two-stage side dam as shown in Figs. is obtained.

That is, even if the solidified shell is crimped with the taper provided, there is a probability that it will protrude to the side. The arrangement shown in FIG. 8 can also deal with such a case.

This point will be explained below with reference to FIGS. 8 and 9.

First, molten metal 2 is pooled in two drums 1 and 15 (
Figure 9). This molten metal 2 is placed on the 150° side of the drum and is prevented from leaking to the side by a nine-sided dam.

The side dam is divided into two parts: a molten metal pool side dam 5 and a solidified shell compression bonding side dam 3.

Note that the drums 1 and 15 are supported by a stand 7.11 (by a bearing tube 9.10 into which the shaft 8 and the shaft 40GC are inserted), and the drums 1 and 15'i are moved in the directions of the arrows (Fig. 9). The thin plate 18 is manufactured only by rotating the shaft 8.

The side dam 5 that pools 2 tons of molten metal is pressed tightly against the sides of the drums 1 and 15 by the brackets 6 attached to the stands 7 and 11, and prevents the molten metal 2 from leaking to the sides. prevent.

On the other hand, since the side dam 3 is provided below the side dam 5 and is pressed against the sides of the drums 1 and 15 by the spring 4 at the solidified shell crimping part 12, the material is moved laterally at the solidified shell crimping part 12. If pressure Ps is generated as the side dam 3 tries to protrude, the side dam 3 escapes to the side, and the pressure generated in this portion corresponds to the force of the spring 4. Therefore, if the force of the spring 4 is appropriately selected to be sufficiently small, the pressure P- acting on the side surface of the side dam 3 can be reduced, so the sliding wear on the side surface of the side dam is small and the wear life is shortened. can be significantly improved.

FIG. 10 shows an example in which a fireproof box 14 is installed above the drums 1 and 15. In this case as well, the lateral length id dam is composed of the tid dam 5 that pools the molten metal 16 and the side dam 3 of the crimped portion 12 of the solidified shell 41, 42, and the latter side dam can be retracted to the side. ing.

In both the cases shown in FIGS. 8 and 9 and the case shown in FIG. 10, the drum has the first rj! J.I.C.
As shown, a drum having a tapered recess at the end of the body is used.

As another application example, when the present invention is applied to a device that moves two drums point-symmetrically to change the plate width, as shown in Japanese Utility Model Application No. 58-152350, , may be performed as shown in FIG.

That is, the taper 50t of the above embodiment is provided only on one side of the end of the drum that can move in the axial direction (in the direction of the arrow in the figure),
The side dam 62t may be pressed against the end surface of the drum provided with the taper 5o.

In addition, the actual specifications of the thin plate continuous casting machine implemented in the present invention will be shown below.

The drum is approximately 600-1200mφ and width 600-160m
0 favor is used. As a result, the thickness is 2 to 5 m,
@ Casting speed of 20~ for thin plates with dimensions of 600~1600m
It can be manufactured at 60m/-.

The material of the thin plate to be cast is ordinary steel, stainless steel,
Various materials such as aluminum are possible.

The taper 50 at the end of the drum body shown in FIG. 1 may be selected, for example, as follows.

In other words, if the thickness of the cast product is h, and the sum of the thicknesses of the two solidified shells before crimping formed using the twin drums is H, then the rolling amount ΔH due to the crimping of the solidified shells at the center of the drum is H - h.
It is.

ΔH/H is expressed in mm and is called the rolling reduction ratio, and the rolling reduction ratio r is usually set at 0.05 to 0.28 degrees.

Therefore, the amount of the tapered recess may be set so that the rolling reduction ratio r=o at the end of the body.

H”:5wa%h=4tea, ΔH=:1m,
If r=0.2, in this case, the amount of the taper recess on one side of the end of the drum body should be around 0.5 cm.

In this way, sufficient reduction is achieved in the center of the drum, but
At the end of the body, r=o, that is, there is almost no rolling down, so no lateral protrusion occurs.

〔Effect of the invention〕

As detailed above, in the present invention, for at least one of the drums used in the twin-drum continuous casting machine, the surface of the drum that forms the solidified shell and faces the widthwise end of the slab. Since the drum diameter on the drum surface is smaller than the drum diameter on the drum center side, even if the solidified shell formed on the surfaces of the two drums is crimped and rolled at the narrowest gap between the twin drums, the rolling reduction rate at the end of the drum body is small. can be kept around zero, so there is no lateral protrusion due to crimping of the solidified shell.Therefore, the lateral pressure on the side dam is slight, and the occurrence of sliding wear on the dam can be prevented, extending the life of the side dam. The work of twin-drum continuous casting can be stabilized.

[Brief explanation of the drawing]

1 to 3 are diagrams showing examples of the shape of a drum used in a twin-drum Dalian #j machine according to an embodiment of the present invention and examples of its use, and FIG. 1 is a schematic plan view of the drum shape. , second
Figures 4 and 5 are explanatory diagrams showing the crimping situation of the solidified shell, Figures 4 and 5 are diagrams explaining all the causes of pressure acting on the side dam in a conventional twin-drum continuous casting machine, and Figures 6 and FIG. 7 is a diagram showing an example of the shape of a drum according to another embodiment of the present invention;
Fig. 8 and Fig. 9 are diagrams showing a case in which the present invention is applied to a two-stage type dam. Fig. 8 is a front view, Fig. 9 is a side view, and Fig. 10 is a case where the present invention is applied to a box fireproof Figure 11 is an explanatory diagram showing the pressure generation situation when the solidified shell is crimped, and Figure M12 is a side view showing the case where the present invention is applied to a rolling type double drum continuous casting machine. FIG. 3A is a schematic plan view, and FIG. 2B is a cross-sectional view of FIG. 1.15... Drum, 2.16... Molten metal, 3.5°20... Side dam, 4... Spring, 12...
- Solidified shell crimping part, 14... Fireproof box, 17-19
... Slab, 30, 31, 40, 41 ... Solidified shell, 5
0... Taper (dent), 53... Taper, 54...
・Parallel part, 55.56, 60.61...Drum, 62
,63...Side dam.

Claims (1)

[Claims] 1. Side dams are provided on the sides of two rotating drums,
During this time, the molten metal is pooled, and while the two drums are rotated to faces facing each other, the pooled molten metal is cooled and a solidified shell is formed on the surfaces of the two drums, and furthermore, a solidified shell is formed on the surface of each drum. In a continuous casting machine that produces a thin plate by pressing the solidified shells together at the narrowest gap between the two drums, for at least one drum, the surface of the drum that forms the solidified shell and the end in the width direction of the slab A twin-drum continuous casting machine characterized by using a drum in which the diameter of the drum surface facing the drum is smaller than the diameter of the drum on the center side of the drum. 2. The twin-drum continuous casting machine according to claim 1, wherein a tapered recess is provided at an end of the at least one drum to reduce the drum diameter.