JPS6238739A - Method and apparatus for producing vertically short sheet ingot - Google Patents

Abstract

PURPOSE:To improve production efficiency, yield, etc. by pulling up a tundish nossle simultaneously upon completion of casting, then removing a partition side plate and executing rapping while moving a casting mold in an opposite direction. CONSTITUTION:The tundish 5 is vertically movably disposed via a supporting stand 6 and four hydraulic cylinders 7 to the position above the end of the horizontally moving mold 1. Plural supporting device 10 which can successively support the bottom surface of a slab S detached from the mold 1 are disposed below the mold. The tundish 5 is raised simultaneously upon completion of casting of the slab S. A refractory board 8A and a heat insulating material 11 are then removed and the partition side plate 1D is removed. A driving carriage 2 is moved backward and the ejected slab S is supported by successively floating the supporting members 10A, by which the rapping is executed. The improved production efficiency, yield, safety, etc. are attained from the shortened time for the rapping, the reuse of parts, etc.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention uses a mold with a large horizontal cross-sectional area and a low height to solidify molten steel in one direction from the bottom surface to the top surface to form a vertical and short steel ingot. It relates to a manufacturing method and an apparatus for carrying out this method.

(Prior art and its problems) This type of mold mainly heats the plate from the bottom surface, rather than cooling from the side, and solidifies the molten steel in one direction from the bottom surface to the top surface, resulting in final solidification. Various methods have been implemented because the edges can be limited to the very surface, and steel ingots without center segregation or hollow defects can be produced with good yield.

As a method for manufacturing such vertically short steel ingots, a variable casting space is formed by providing a weir that partitions the inside of the mold in a horizontally movable mold that is freely movable in the horizontal direction. There is a method in which molten steel is injected from a tundish nozzle into the molding space, and the molten steel is solidified in one direction from the bottom surface to the top surface while moving a horizontally moving mold.
After casting was completed and the slab had completely solidified, the tundish and weir were removed, the mold was then lifted up by a crane, the mold was turned over at a location away from the casting equipment, and the slab was removed. There were some problems.

(a) Removal of the tandish and weir is all carried out using a crane, which takes a lot of time.

('b) It takes time to transport.

(C) The mold is severely damaged during reversal.

(d) For the above reasons, the heat of the slab cannot be used effectively.

This invention was proposed to solve these problems, and its purpose is to improve productivity, yield, workability, and safety by easily and quickly cutting out slabs.
Moreover, it is an object of the present invention to provide a method for manufacturing a vertically short steel ingot and an apparatus for manufacturing the same, which can effectively utilize the heat of the slab.

(Means for Solving the Problems) The method for manufacturing a vertically short steel ingot according to the present invention is that, at the same time as casting is completed, the tundish nozzle is pulled up from the molten steel, and the heat insulating agent is removed using a dry slag remover or the like. The mold partition side plate on the casting side was removed, the horizontally moving mold was moved in the opposite direction to the direction used during casting, and the lower surface of the extruded slab was successively supported so that the mold could be easily and quickly removed. It is something.

The apparatus for producing vertical and short steel ingots according to the present invention is formed into a box shape with four surrounding side plates and a surface plate at the bottom, and the mold partition side plate, which is the short side on the casting side, is removable. A movable horizontally movable mold, a weir that partitions the inside of the mold to form a variable casting space, and a fireproof board that is vertically removable at the front of the casting side, and a tundish nozzle located near the fireproof board. a tundish installed above the weir so as to be vertically movable by a hydraulic cylinder, etc., and a mold moving device that horizontally moves the horizontally moving mold in the casting direction and in the opposite direction. and a plurality of support devices disposed below the horizontally movable mold, which are movable up and down and capable of sequentially supporting the lower surface of the slab detached from the horizontally movable mold when running in reverse in the opposite direction to the casting direction, At the same time as casting is completed, the tundish nozzle is lifted out of the molten steel by raising the tundish, the weir remains in place, and only the fireproof board is pulled out, the heat insulator is removed, the mold partition side plate is removed, and complete solidification is achieved. After confirming this, the mold is moved in the opposite direction to the casting direction, the lower surface of the extruded slab is successively supported by a support device, and the mold is removed.The slab is then lifted up by a crane equipped with a special jig. It is designed to be sent to the process.

(Embodiment) The present invention will be described below based on an illustrative embodiment.

As shown in Fig. 1, the horizontally movable mold 1 is formed into a box shape by four surrounding side plates IA, IB, IC, LD and a bottom surface plate IE, and the mold partition side plate ID is the short side on the casting side. can be attached and detached in the vertical direction by the engagement grooves and hanging rings of the side plates IA and IB.

Such a horizontally moving mold is driven by a drive carriage 2. A mold moving device comprising wheels 3 and guide rails 4 allows the mold to move in two directions: the sand casting direction and the opposite direction.

Above the end of the horizontally movable mold 2, a tundish 5 is straddled by a support pedestal 6 and can be moved up and down by four hydraulic cylinders 7.At the bottom of the tundish 5, there is a tundish 5 that can be moved vertically by partitioning the inside of the mold. a weir 8 forming a casting space;
A tundish nozzle 9 located near this weir 8 is attached.

The weir 8 is vertically movably connected to the tundish 5 and is pressed against the surface plate IE by a spring or the like. This weir 8 is made of cast steel or the like, and a fireproof board 8A made of a 5in2 type refractory is attached to the front part on the casting side via a fireproof board jig 8B made of a Cu alloy or the like (see Figure 3). ).

The fireproof board jig 8B and the weir 8 are connected to the T-study section by a single-shaped groove, and the fireproof board 8A is vertically removable.

A plurality of supporting devices 10 are disposed below the horizontally movable mold 2 and can sequentially support the lower surface of the slab S that is separated from the horizontally movable mold 1 during reverse running in the opposite direction to the casting direction.

This support device 10 consists of a support member 10A in the shape of a mouth along the width direction of the slab, and hydraulic cylinders 10B arranged at both ends of the support member 10A to move the member 10A up and down. Still, this support device 10 is operated sequentially in synchronization with the mold movement speed by a timer or limit switch (not shown).

During casting, an initial casting space is set, and molten steel is poured into the tundish nozzle 9. When the molten steel is poured to a certain height, the horizontally movable mold 1 is moved. The upper surface of the molten steel in the mold is kept warm by a heat insulating agent 11 such as SiO2, cooled by a water cooling nozzle 12 at the lower part, and solidified in one direction from the lower surface to the upper surface.

Once the casting is complete, the mold is removed using the following process.

(1) Raise the tundish 5 at the same time as casting is completed. In conventional tundish nozzles, the tundish nozzle was forcibly broken and removed after complete solidification, but this was disadvantageous in terms of slab yield, and It takes time to remove it.

Therefore, in the present invention, the entire tundish 5 is floated by the hydraulic cylinder 7 or the like at the same time as the casting is completed.

Note that this provides sufficient space between the tandish and the mold, making it easier to pull out the next fireproof board.

Φ) Remove fireproof board 8A.

The conventional fireproof board was directly attached with bolts, but since it can be easily removed using the jig 8B, the fireproof board 8A can be reused. Moreover, by removing the fireproof board 8A, there is no unnecessary material between the weir and the slab, and extrusion can be easily performed.

(E) Heat insulating agent 11 for well-known dry suction sludge remover 13, etc.
remove. The heat insulating agent 11 exists between the top surface of the slab, the side plate, and the slab, and by removing it, foreign matter is prevented from being caught between the weir and the surface plate, and smooth extrusion is possible.

Remove the mold partition side plate ID using a crane.

(V) The drive motor of the drive truck 2 is reversed to move the horizontally movable mold 1 in the opposite direction to the casting direction, and the slab S is pushed out of the mold 1.

At this time, since warping occurs as a characteristic of the slab, the contact area between the surface plate and the slab is less than 1/4, and sufficient extrusion is possible with approximately 1.2 times the force required during casting. be.

In addition, it is necessary to select a material with sufficient strength and hardness for the roaring part of the slab of the weir.

(b) The support member 1 of the support device 10 is synchronized with the reverse feeding of the mold.
0A is floated one by one to support the lower surface of the extruded slab.

(vii) The slab is 90% or completely bearing device 1.
When it reaches zero, it is transferred to the next process using a crane equipped with a special jig.

A tongs type jig, which is normally used for conveying slabs, is sufficient.

Note that thin slabs are directly charged into the heating furnace (thin segregation areas are removed as scale), and thick slabs are hot-scarved at the surface segregation areas, charged into the heating furnace, and rolled (hot charge). .

(Effect of the invention) As described above, according to the present invention, upon completion of casting, the tundish nozzle is pulled up from the molten steel, the heat insulating agent is removed, the partition side plate is removed, the mold is run backwards, and the extruded steel is extruded. Since the lower surface of the slab is successively supported and die cut is performed, the following effects are achieved.

(i) Conventionally, from the time a slab is taken out to the time it is sent to the next process,
However, in the present invention, mold removal can be completed in about 30 minutes after complete solidification, so the amount of time needed to send it to the next process can be reduced to about IHr. This enables hot charging by direct delivery or hot scarfing.

(ii) Most of the work that has traditionally been done by humans in hot conditions has become automated, making it possible to perform the work safely.

(L]■ By floating the tanditsh, the nozzle part can also be used fully as a finished product, so the yield was improved by about 10%.

Since there is no longer a need to remove the mold, the preparation time has been significantly shortened, and the production efficiency has tripled from 1 charge per 8 hours to 3 charges.

(v) If the fireproof board is made removable, it becomes fully possible to reuse the fireproof board, and the board has actually withstood 15 charges.

A: Through the above steps, a stable slab can be obtained.

The manufacturing apparatus according to the present invention has a relatively simple configuration, and has the following features:
The die cutting described above may be performed.

[Brief Description of the Drawings] Figures 1 and 2 are longitudinal and cross-sectional views showing the manufacturing apparatus according to the present invention, Figure 3 is a plan view showing a weir, and Figure 4 is a state in which the slab is being drawn. FIG. 1...Horizontal movement mold LA, IB, IC, ID...Side plate, IE...Surface plate 2...
Drive truck, 3...Wheels 4...Guide rail 5...Tandish, 6...Support frame 7...Hydraulic cylinder, 8...Weir 8A...Fireproof board, 8B...Fireproof board jig 9...Tandish Nozzle 10...Support device 10A...Support member, IOB...Hydraulic cylinder 11...
Heat insulator, 12...Water cooling nozzle 13...Suction sludge remover

Claims (2)

[Claims] (1) In a horizontally movable mold that can be moved freely in the horizontal direction,
A variable casting space is formed by providing a weir that partitions the inside of this mold, and molten steel is injected into this variable casting space from a tandate nozzle, and the molten steel is poured from the bottom surface to the top surface while moving the horizontally moving mold. In the method of manufacturing vertical and short steel ingots by solidifying in one direction, at the same time as casting is completed, the tandate nozzle is pulled up from the molten steel, the heat insulator is removed, and the mold partition side plate on the casting side is removed. A method for manufacturing a vertically short steel ingot, characterized by moving a horizontally movable mold in the opposite direction to the direction of casting, and sequentially supporting the lower surface of an extruded slab to perform mold cutting. (2) It is formed into a box shape from the four surrounding side plates and the bottom surface plate, and the mold partition side plate, which is the short side on the casting side, is removable.
A horizontally movable mold that can move freely in the horizontal direction, a weir that partitions the inside of the mold to form a variable casting space and has a refractory board that can be attached and removed in the vertical direction at the front of the casting side, and a tandate nozzle. a tundish which is installed vertically so as to be located near the fireproof board, and which is installed above the weir so as to be vertically movable; and a mold moving device that horizontally moves the horizontally moving mold in the casting direction and in the opposite direction. , A plurality of support devices are disposed below the horizontally movable mold, are movable up and down, and are capable of sequentially supporting the lower surface of the slab detached from the horizontally movable mold during reverse movement in the opposite direction to the casting direction. An apparatus for producing vertical and short steel ingots.