JPS6240956A - Casting device for thin sheet - Google Patents

Abstract

PURPOSE:To produce a thin metallic sheet having an excellent surface characteristic and uniform thickness by providing a rear surface stationary gate and side face moving gates lined with a refractory heat insulating material on the inside on an endless metallic melt, pouring a molten metal to the prescribed position of a molten metal pool formed of both gates and cooling the same. CONSTITUTION:The metallic belt 11 is put on pulleys 12 to form an endless track rising on a casting direction and a cooler 13 is installed to the lower part. The rear surface stationary gate 15 is brought into elastic contact with the surface of the belt 11 and the side face moving gates 14 are brought into contact with the belt so as to move in synchronization with the belt 11. The surfaces of both gates 14, 15 which contact with the molten metal are lined with the refractory heat insulating meterial 24. The molten metal pouring flow 17 from a pouring device 16 is poured into the molten metal pool 18 formed of both gates 14, 15 in the position spaced by a prescribed distance from the gate 15 (at least about 100mm apart from an ingot ejection side and within about 80% of the length of the molten metal pool). The solidification start point is thereby made uniform and a solidified layer 19 from the pool 18 is rolled by rolling rolls 20 and is coiled by a coiler 21, by which a thin sheet coil 22 is produced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a single-sided solidification continuous casting apparatus for producing sheet metal such as copper strip.

BACKGROUND OF THE INVENTION Conventionally, in order to produce a thin metal plate, such as a thin steel plate, a steel ingot is bloomed to obtain a slab with a thickness of 200 to 250 mm, and this slab is hot rolled in a hot strip mill, or molten steel is rolled. The process involves continuous casting to obtain a slab, which is then hot rolled.

However, since these conventional techniques require large-scale hot strip mills and energy to heat the slab, it is desired to develop a technique for directly obtaining thin plates by continuous casting of molten steel.

Conventionally, when continuously casting molten steel, a method has generally been used in which the molten steel is poured into a mold, solidified around the cross section, and then pulled out with f force. However, with this method, it is difficult to obtain slabs with a thickness of several tens of centimeters or less due to the relationship between the diameter of the nozzle for injecting molten steel into the mold and the cross-sectional dimensions of the mold. Due to the friction between the walls, it is difficult to increase the slab drawing speed above 2m/1lin;
There was a problem that if the temperature was lower than 7, there was a risk that the solidified shell would break and a flow of molten steel would blow out (breakout).

In order to solve these problems in the conventional continuous casting process and provide an efficient manufacturing method by continuous casting of thin plates and an apparatus therefor, the present inventors previously filed a patent application filed in Japanese Patent Application No. 58-1
In No. 88882, a method and apparatus for manufacturing thin metal sheets by single-sided casting was proposed.

In other words, it is a method of casting thin steel plates by pouring molten steel onto a flat plate forming an inclined endless track, in which the casting direction and the direction of the poured molten steel flow are reversed, that is, the flat plate forming an endless track moves upward on the slope. A method for continuous casting in which molten steel is poured onto a flat plate under such conditions that the lower end of the molten steel (molten metal) flow on the tilted moving flat plate is self-held by the surface tension of the molten steel, and a method in which the molten steel is driven by a drive wheel. A belt e structure having an endless track and an inclined plane, a means for supplying molten metal downward onto the inclined plane, a device for extracting slabs on the side of the inclined surface, and a driving wheel for the belt. This is a continuous casting device for molten metal, which consists of a device that is driven upward through a slope.

With this technique, steel plates with a thickness of 2 to 20 mm, for example, can be produced by continuous casting. According to this technology, molten steel (molten metal) solidifies on a track plane that is inclined and moves upward, and the extraction speed of the solidified shell (slab) and the moving speed of the track plane (belt) are synchronized. If so, breakout due to friction between the belt surface and the slab will not occur, so the casting speed can be dramatically increased.

In addition, since it is one-sided solidification, the bottom surface of the slab is in contact with the belt surface during casting, but the top surface is in contact with the molten steel or the atmosphere, and since there is no space constraint such as a mold, the molten steel is transferred from the tundish to the molten steel. There are no problems with the nozzle arrangement for supplying the water.

The present inventors have further improved this technique and installed a fixed weir extending in the width direction of the metal belt at the lower end of the molten metal injection flow so as to be in elastic contact with the metal belt. )
-1- A patent application filed in 1983 to solve the problem of wrinkling of slabs caused by the uneven planar shape of the tip of the molten metal injection flow in metal belts by forming a molten metal pool in -1-.
It was proposed in No. 120588.

However, in these techniques, the side edges that regulate the side edges of the slab are fixed and made of metal.

In a continuous thin plate casting apparatus of a single-sided solidification type having such a fixed side surface, the slab being solidified is restrained by the side surface and, as shown in FIG. 3, its back surface is cooled with cooling water 4. In the pool 2 formed on the endless metal belt 3, solidification of the portion in contact with the side surface 1 progresses, forming a so-called "ear" 5 in the cast thin plate.

When "ears" are formed on the side edges of a cast sheet, it not only becomes extremely difficult to roll up the cast sheet, but the uneven thickness must be removed after casting, which reduces yield. There were problems such as a decrease in

Problems to be Solved by the Invention The present invention solves the problems in the prior art described above, and makes it possible to obtain a thin metal plate having a uniform thickness.
The purpose of this project was to provide a continuous thin plate casting device of one-sided solidification type.

Means for Solving the Problem The gist of this invention is to provide a molten metal pool externally supplied to an endless metal bell (h) with a cooling device inclined so that the casting direction is -1- upward. This is a track-type single-sided coagulating device that is equipped with a fixed rear weir and a moving side weir to form an endless metal belt. It extends in the width direction of the belt and is lined with a refractory heat insulating material on the side in contact with the cast metal, and the molten metal injection flow is positioned at a predetermined distance in the casting direction from the rear fixed weir, and the side movable weir is a lower end surface of the endless metal belt is in contact with the "-" surface of the endless metal belt;
It is located in a thin plate casting machine that moves in synchronization with an endless metal belt and is lined with a refractory heat insulating material on the side that comes into contact with the cast metal.

The present invention will be explained in detail below with reference to the embodiments shown in FIGS. 1 and 2.

FIG. 2 shows an overall view of this inventive device.

In Figure 2, II is a metal belt and pulley 1
2 to form an endless track. Reference numeral 13 denotes a cooling device that cools the metal belt II during the casting process from its back side. 14 is a lateral moving layer (hereinafter referred to as lateral part)
It is composed of a chain of heat-resistant blocks that are wound around a sprocket wheel (not shown) to form an endless track, and is driven in synchronization with the metal pels 1-11.

Reference numeral 15 denotes a rear fixed weir (hereinafter referred to as the rear surface part) whose lower surface is in contact with the upper surface of the metal belt and is elastically pressed against the surface of the metal belt by, for example, a spring. Reference numeral 16 denotes an injection device, which is disposed at a predetermined distance from the rear bottle 15 in the casting direction so that an injection stream 17 is positioned therein.

Reference numeral 18 denotes a water reservoir, which is formed on the surface of the metal belt 11 in a space surrounded by the rear surface portion 15 and the side surface portions 14 with molten metal supplied from the injection device 16.

18 is a solidified thin plate, that is, a slab, which is extracted from the pool 18 on one side of the slope formed by the metal belt 11, and is rolled or surface-shaped by a rolling roll 20;
It is wound up by a winding device 21 to form a thin plate (strip) coil 22.

In Fig. 1, a side view of the device shown in Fig. 2! 4 is shown.

In FIG. 1, reference numeral 24 denotes a heat insulating refractory lining, which is disposed on the side of the side surface 14 that contacts the molten metal (pool 18).

The inventors of the present invention, in the process of researching a single-sided solidification type thin plate casting process as shown in FIG. It has been discovered that this method can effectively solve the problem of "ear" formation in M-shaped strips (thin plates).

Preferably, the side of the rear portion 15 shown in FIG. 2 that is in contact with the sump 18 is also lined with an insulating refractory material. Because of this, the rear section 15 is called "cold shut".
It is possible to eliminate the occurrence of sharp grooves (discontinuities) extending in the width direction of the cast thin plate due to the adhesion of solidified shells to the cast thin plate.

The working metal belt 11 is for example 70
It is driven at a speed of m/ll1in. At the same time, the side portion 14 is also driven in synchronization with the metal belt 11 by a sprocket wheel (not shown).

Molten metal, such as molten steel, is injected from a pouring device 16 into a space formed on the inclined surface H of the metal bell 11 by the rear surface portion 15 and the side surface portions 14, thereby forming a pool 18.

The back surface of the metal bell [1 is water-cooled by a cooling device 13 during the casting process starting from the rear surface portion 15.

Then, solidification begins on the surface of the metal belt 11 that has passed through the lower surface of the rear surface part i5 at the lower part of the molten metal pool 18, and a solidified layer develops under the surface of the molten metal, and the metal belt is formed as a thin plate (slab). 1
1 is extracted in the side-L direction.

In this invention, the technical problem in the invention is
The position of the injection stream 17 is important as a means of solving the problem of obtaining a thin plate with excellent surface properties (no wrinkles, double skin, etc.) and uniform thickness by continuous casting with high productivity. .

That is, as shown in FIG. 2, coagulation starts immediately after the rear surface portion 15 of the metal belt 11. Due to the existence of this rear surface portion 15, the solidification start point on the entire surface 1- of the metal belt 11 becomes uniform, and the solidification start point is caused by non-uniformity of the solidification start point.
The formation of hot water wrinkles, double skin, non-uniform coagulation layer thickness, etc. can be prevented.

If the injection flow 17 is located at or near the rear surface portion 15, the solidification start point will be disturbed, and since the solidified shell thickness is thin, the solidified shell once solidified will be remelted and the surface quality will be improved. It also makes it difficult to extract thin plates (slabs) of uniform thickness.

Furthermore, after the solidified layer (slabs) have been extracted from the molten metal pool 18, or if the injection stream 17 is located at the end of the molten metal pool 18 on the slab extraction side, the heat of the injection stream 17 will be reduced. The energy of the fall overturns the solidified layer that has developed up to that point, damaging the surface quality of the thin plate (#8 piece) and making the thickness non-uniform.

According to the research of the present inventors, injection yk17
For the reasons stated above, it is necessary to locate the metal sump 18 at least 100+adi from the slab extraction side surface of No. 5 and within 90% of the length of the metal belt moving direction of the sump 18.

Now, the thin plate (slab) I8 extracted from the tundish 18 is further rolled or shaped by a pair of rolling rolls 20,
The winding device 21 winds up the thin plate (strip).
A coil 22 is used.

Effects of the Invention This invention enables manufacturing thin metal sheets with excellent surface quality and uniform thickness with high productivity without any fear of breakouts or fractures. This greatly simplifies the process, resulting in significant energy savings and cost savings.

[Brief explanation of the drawing]

FIG. 1 is an elevational sectional view showing the side base of the thin plate casting apparatus of the present invention, FIG. 2 is an elevational view showing the entire thin plate casting apparatus of the present invention, and FIG. 3 is an elevational sectional view showing the conventional side base. It is. 1-- Side group, 2... Reservoir, 3... Belt, 4
...cooling water, 5Φ...ear, 11...metal belt, 1
2... Pulley, 13... Cooling device, 14... Side base, 15... Rear base, 16... Injection device, 17...
... Injection flow, 18... Hot water pool, 1906. solidified thin plate,
2o...rolling roll, 21...winding device, 22...
...Thin plate coil, 24...Insulation 1 Refractory lining.

Claims (1)

[Claims] 1. An endless track type with a fixed rear weir and a movable side weir to form a pool of molten metal supplied from the outside on an endless metal belt equipped with a cooling device that is inclined so that the casting direction is upward. In the single-sided solidification device, at least a part of the lower surface of the rear fixed weir is in elastic contact with the upper surface of the endless metal belt, extends in the width direction of the endless metal belt, and is lined with a fireproof heat insulating material on the side in contact with the cast metal. The molten metal injection flow is positioned at a predetermined distance from the rear fixed weir in the casting direction, and the side movable weir has its lower end surface in contact with the upper surface of the endless metal belt, and is synchronously moved with the endless metal belt. Sheet casting equipment that moves and is lined with refractory insulation on the side that comes into contact with the cast metal.