JP2000272751A - Underwater casting conveyor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an underwater casting conveyor capable of stably operating a mold conveyor when filling high-temperature molten object beyond the treatment capacity of the mold conveyor immersed in water. SOLUTION: An underwater casting conveyor is provided for cooling and coagulating high-temperature molten object containing metal and slag with a plurality of molds mounted in series to an endless conveyor immersed in water. Each of the molds is formed of a front wall and side walls of a mold frame 10 at the front side in the direction of moving the conveyor, followed by part of a front wall of a mold frame 10' at the rear side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an underwater casting conveyor used for cooling and solidifying molten metal or slag in water.

[0002]

2. Description of the Related Art Generally, in an ironworks, etc., dust is charged into a reduction melting furnace such as a rotary kiln for reduction melting in order to recycle dust containing metal components generated in iron making. 2. Description of the Related Art It has been practiced to cool and solidify discharged valuable metals and slags into required shapes. There is a method of cooling and solidifying by immersing a conveyor in which a number of molds are continuously mounted in water, and such a conveyor is called an underwater casting conveyor. In the underwater casting conveyor, it is required that the mold release of the solidified material from the mold is good, and that it can be operated stably regardless of the amount of the molten material. Needless to say, the use of such an underwater casting conveyor is not limited to steel works, but is applied to all fields in which molten metal or slag is cooled and solidified in water.

As an example of using the above-described underwater casting conveyor, Japanese Patent Application No. 9-129501 proposes a "metal recovery method and recovery apparatus". In this example,
An endless mold conveyor equipped with a large number of molds is continuously immersed in a water tank storing the stored water at a predetermined water level, and a device for sequentially transporting the melted water is provided, and the melt is continuously dropped from above the water tank. Thereby, cooling and solidification is performed. In this mold conveyor, the open end of the mold is the upper part, and the mold is a concave integral body. The problem in this case occurs when a large amount of molten material more than the volume of one mold is injected at a time. That is, since the speed of cooling and solidification of the melt in water is much faster than in the atmosphere, the melt solidifies over a plurality of molds that are continuous in the traveling direction of the mold conveyor. In this case, solidified matter prevents the relative change in the relative position with the adjacent mold, such as a rotating part of a sprocket that drives the mold conveyor, causing mechanical parts such as conveyor chains to bend. Or breakage may hinder continuous stable operation.

In addition, for example, the drop between the upper open end of the mold immersed in water and the discharge end of the melt is 800 to 18
When the distance from the opening end of the mold to the water surface (water depth) is 50 to 200 mm, the depth of the upper opening end of the mold becomes large when a large amount of molten material is injected as described above. Since the object itself has a large amount of heat, welding between the mold and the molten material may occur and the mold may not be separated.

[0005]

The above problems will be described below with reference to the drawings. FIG. 8 shows an example of using an underwater casting conveyor. In FIG. 8A, the stored water 8
An endless mold conveyor 83 on which a number of molds 82 are mounted is immersed in a water tank 80 in which 1 is stored at a predetermined water level. The mold conveyor 83 is driven in one direction.
Cooling and solidification is performed by dropping and injecting a high-temperature melt from above the water tank 80 continuously into the mold conveyor 83.

When the high-temperature molten material is injected into the mold 82 of the mold conveyor 83, if the injection amount can be controlled to a constant amount, the size of the mold 82 and the moving speed of the mold 82, that is, the conveyor speed, etc. are arbitrarily set. By doing so, a stable casting can be manufactured. However, when the injection amount is not constant, for example, when the ratio between the maximum amount and the minimum amount is 10 times or more, it is not possible to cope only with the conveyor speed. In other words, when a high-temperature melt exceeding the processing amount is injected into the mold 82 immersed in water, the high-temperature melt overflowing from the mold 82 flows out from the adjacent mold 82 or the side walls at both ends of the mold 82. To try. However, in water, the solidification by cooling is fast, and the solidified material in each frame may not be cut off at the upper end of the wall constituting the mold 82 and solidified as an integrated material.

In this case, as shown in an enlarged manner in FIG. 9, the solidified material 84 is solidified across a plurality of molds 82 in the conveyor traveling direction. In this case, in the conveyor head portion 86 that drives the conveyor chain 85, the adjacent mold 82 must change its relative position at the bent portion 87, whereas the solidified material 84 may hinder the change. . In this bent portion 87, the solidified material 84 is 88
When it is impossible to break or bend as shown by, the conveyor chain 85 stops, and continuous stable operation cannot be performed.

The same applies to the other bent portions 89 of the mold conveyor 83 shown enlarged in FIG. 8B, and the solidified material 84 solidified over a plurality of molds 82.
Prevent the relative position change of the adjacent mold 82.
As a result, the conveyor chain 85 is
There is also a situation in which the terminal rises from zero and derails.

When the strength of the conveyor chain 85 and the mold 82 constituting the mold conveyor 83 is weaker than the force of bending or breaking the solidified material 84, the conveyor chain 85 and the mold 82 are damaged.

On the other hand, when the unit weight and dimensions of the casting are set to a desired size, as shown in FIGS.
01 in the width direction of the conveyor, that is, in the direction perpendicular to the traveling direction of the conveyor, as appropriate.
Put 2 and divide. However, when the height of the middle partition 102 is the same as or higher than the side walls 103 at both ends of the mold 101 in the conveyor width direction, as shown in FIG. A situation occurs in which only a small amount flows into the other sections. And, at that time, the casting shape of the section into which only a small amount has flowed, the ratio of the desired weight and the ratio deviating from the allowable range of the dimensions,
The height of the middle partition 102 is higher than when the height is lower than the side walls 103 at both ends. Therefore, the yield of the cast article is deteriorated.

In FIG. 10, when a high-temperature molten material having a capacity larger than the above-mentioned mold conveyor processing capacity is injected,
Since the heat capacity of the mold itself is small at the upper end portion 104 of the side wall of the mold 101, when heat is supplied one after another from a large amount of high-temperature molten material, the temperature of the mold 101 locally becomes close to the temperature of the molten material. When the melting point of the material is exceeded, the supplied high-temperature molten material and the mold 101 are fused. When the high-temperature molten material and the mold 101 are fused, the solidified material does not separate from the mold 101, and the stable operation of the conveyor becomes impossible. This phenomenon is related to the depth at which the mold 101 is disposed in the water, and the shallower the phenomenon, the more frequently the phenomenon occurs.

Further, when supplying the molten metal and the slag to the mold conveyor immersed in the water, the above-mentioned “metal recovery method and recovery apparatus” simultaneously supplies the molten metal and the slag. Since the cooling rate is high, slag is likely to be mixed into the metal. Further, the slag separated in specific gravity is in contact with the metal surface solidified at the upper end opening of the mold. However, depending on the cooling rate, there are many cases where the entire surface is not covered well and a cavity is formed in the metal or the solidified metal contains moisture.

The present invention is directed to a submerged conveyor which is capable of operating the conveyor stably even when a high temperature molten material exceeding its processing capacity is injected by a conveyor immersed in water and continuously immersed in a large number of molds. It is to provide a casting conveyor.

[0014]

SUMMARY OF THE INVENTION The present invention relates to an underwater casting conveyor in which a high-temperature melt containing metal and slag is cast and cooled and solidified in a plurality of molds continuously mounted on an endless conveyor immersed in water. Each mold is characterized by comprising a front wall and a side wall of a mold frame on a front side with respect to a conveyor traveling direction and a part of a front wall of a mold frame on a rear side subsequent thereto.

The mold frame has a bottom wall, a plurality of side walls, and a front wall on the front side with respect to the traveling direction of the conveyor.
The rear wall of the mold frame is constituted by the front wall of the rear mold frame following the mold frame, and the cross-sectional shape of the front wall is chevron-shaped, and the front wall of the mold frame immediately before the mold frame is formed. One mold frame is fixedly arranged on one conveyor chain so as to overlap with the bottom wall.

The front shape of the front wall of the mold frame has a radius r larger than a distance R from a pin center C1 on the rear side of the conveyor chain to which the mold frame is fixed to the front surface of the front wall, The conveyor chain has an arc shape centered on a point C2 that is eccentric downward from the pin center C1.

The mold frame is divided by at least one partition in a direction perpendicular to the conveyor traveling direction, and the plurality of side walls and the front surface of the rear mold frame adjacent to the partition in the conveyor traveling direction. The partition is located proximate to a wall, and the partition is lower in height than the plurality of side walls.

In the mold frame, a raised portion is formed on the bottom wall adjacent to the lower end of the front wall of the rear mold frame at a portion overlapping the front wall of the rear mold frame following the mold frame. Provided.

The arrangement of the mold frame is such that adjacent molds can proceed without changing their relative positions from the position where the high-temperature melt is injected until the solidified material is released from the mold. .

It is preferable to provide a cooling means for injecting water at a flow rate of 1 m / sec or more to cool the part of the mold at and near the position where the high-temperature melt is injected.

[0021]

The underwater casting conveyor according to the present invention cools and solidifies a high-temperature molten material containing metal and slag with a plurality of molds mounted on an endless conveyor immersed in water to form one casting. 2 adjacent molds for
It is composed of two mold frames, and the water depth at which they are arranged is not particularly limited, and is determined by the relationship between the maximum supply amount of the high-temperature molten material, the temperature and the melting point of the mold, and the desired casting shape and yield, etc. In order to prevent the phenomenon, the back surface of the mold where the high-temperature melt is injected is water-cooled with cooling water having a flow rate of 1 m / sec or more.

[0022]

Embodiments of the present invention will be described below. FIG. 1 shows a partial cross section of an underwater casting conveyor according to the present embodiment in the conveyor traveling direction. Describing one mold, the mold frame 10 includes a partition 11 having a mountain-shaped (substantially triangular) cross section as a front front wall with respect to the traveling direction of the conveyor, and the rear wall is provided in the subsequent mold frame 10 '. It is constituted by the front surface 12 of the partition 11 '. Mold frame 1
Each of 0, 10 'is firmly attached to the conveyor chain 13 by a plurality of attachment bolts 14.
The bolt insertion hole on the mold frame side may be finished smoothly by welding. As shown in FIG. 2, one or more partitions 15 (here, two partitions) are inserted and divided in the conveyor width direction of the mold frame 10, that is, in a direction perpendicular to the conveyor traveling direction. . The partition 15 is
The height is made lower than the partition 11 and the side walls 16 at both ends. The upper end of the partition 15 may be inclined rearward with respect to the traveling direction of the conveyor. Also, the mold frame 10
The partition 15 and the side walls 16 are used for the subsequent mold frame 10.
′.

Next, a chevron-shaped partition 1 in front of the mold frame.
The shape of the front surface 12 will be described with reference to FIGS. In the conveyor head section 20 having a sprocket for feeding the conveyor chain, adjacent mold frames are places where the relative positions of the mold frames change, and the mold frame 10 is moved from the surface 31 of the solidified material 30 straddling a plurality of mold frames.
However, it is necessary to make it come out without being hindered by the surface 31 of the solidified matter 30. For this purpose, the front 1 of the partition 11
The shape of No. 2 is formed by an arc 23 having a radius r centered on a position C2 shifted downward by the amount of eccentricity e downward from the rotation center C1 of the conveyor chain 13 (position of the pin on the rear side of the conveyor chain 13). I do. The rotation locus 22 of a point P1 on the front surface 12 of the partition 11 in front of the mold frame 10 is a locus whose radius is the distance R from the rotation center C1 of the conveyor chain 13, and the radius of curvature of the surface of the front surface 12 of the partition 11 is r, and the relationship is R <r. The rotation locus 22 intersects with the arc 23 at the position P2 above the mold. When the conveyor chain 13 rotates by θ as shown by the imaginary line in FIG. 4, the mold frame 10 also opens as the mold frame 10 rotates downward. Becomes larger.

Returning to FIG. 1, a raised portion 17 is provided on the bottom wall of the mold frame 10 in a portion where the subsequent mold frame 10 'overlaps the front surface 12, and the shape thereof is mountain-shaped. Then, as shown in FIG. 4 (b), the raised portion 17 has an arc shape with the center at C2, similar to the front partition 11 of the mold frame 10, and the radius r1 is r1>
The curved surface satisfies R1. R1 is the radius of the rotation locus drawn by a point of the raised portion 17, and is a locus whose radius is the distance R1 from the rotation center C1 of the conveyor chain 13.

Further, a partition 11 in front of the mold frame 10 is provided.
It is desirable to form a cavity 18 so that water can be cooled by passing water through the inside. As for the inner surface shape of the mold frame 10, it is desirable that the corner portion of the inner surface be a curved surface having a large curvature so that the releasability of the solidified material is improved.

As shown in FIG. 5, the arrangement of the mold on the underwater casting conveyor is such that the adjacent mold frames are positioned relative to each other between the melt supply position S and the bending start point D, that is, within the range of the distance L. Arrange them so that their positions do not change. The envelope shape of the arrangement may be a straight line or a curve. For example, as shown in FIG. 6, an arc-shaped arrangement having a center C3 may be adopted. However, the backlash due to the mechanical clearance of the rollers and the receiving part that receives the conveyor chain,
Obviously, it does not matter if it fluctuates.

Returning to FIG. 5, the distance (water depth) H from the water surface 32 of the water tank 31 to the upper end of the mold is not particularly limited, and the maximum amount of the melt supplied to the mold and the temperature are not particularly limited. It should be determined from the viewpoint of preventing fusion between the molten material and the mold, the required shape of the recovered casting, the yield, and the like, from the conveyor speed, the material of the mold, and the like.

The recovered cast article is released from the mold in the water tank 31, and can be taken out of the water tank 31 by a slag pan conveyor 30 or the like arranged at the bottom of the water tank 31.

As shown in FIG. 5, the mold is provided with a plurality of cooling water nozzles 33 on the back side (lower side) of the mold at and near the position where the melt is injected, so that the cooling water flows at a flow rate of 1%. (M / sec) or more to jet and cool. For example, as shown in FIG. 7A, the cooling water nozzle 33 is disposed on the back side of the mold and has three upwardly directed cooling water outlets 33-1 to 33-3. Further, in order to cool through the cavity (18 in FIG. 1) in the partition 11 in front of the mold frame, one or more cooling water outlets for blowing the cooling water in the lateral direction as shown in FIG. Is disposed.

If the primary purpose is metal recovery, it is desirable to first supply the molten metal to the empty mold at location S, and then supply the slag thereover. This is because when the rotary kiln 40 is combined with the apparatus shown in FIG. 5 as a reduction melting furnace, the outlet of the high-temperature melt is set to the position indicated by S in FIG. 5, and the rotation direction of the rotary kiln 40 is set in the counterclockwise direction. Can be realized. That is, in such a combination, since the metal component contained in the high-temperature melt is heavier than the slag component, the metal component comes out of the rotating rotary kiln 40 earlier and is injected into the mold. A light slag component will be injected into the mold.

[0031]

EXAMPLE A submerged casting conveyor of the present invention was immersed in a water tank in a supply system in which a supply amount of a melt containing metal and slag at a temperature of about 1300 ° C. varied in a range of 0 to 50 (t / h). As a result of operating with the distance from the upper end of the mold to the water surface set to 300 mm, even if solidified material straddling a plurality of molds in the direction of travel of the conveyor is formed, it operates stably without disturbing the conveyor operation. I was able to.

The mold has a width of about 800 mm in a direction perpendicular to the direction of travel of the conveyor and has four divisions in the width direction (intermediate partition 3).
), Conveyor width 180mm, side wall height 80m
m, the material is cast steel. The recovered metal castings are 15
It has a rectangular shape of 0 × 50 × 80 (mm ³ ), and a shape yield of 80% was obtained.

[0033]

As described above, when a large amount of melt is supplied to the underwater casting conveyor and the melt solidifies over a plurality of molds in the conveyor traveling direction, first, from the melt supply point S, In the transport path to the casting discharge point D, the plurality of mounted mold frames do not need to change their relative positions, so that the problems of floating and derailment of the mold and the conveyor chain have been solved.

Second, when the conveyor chain and the mold are rotated by the sprocket at the conveyor head, the mold frame can come out of the solidified material without competing with each other. Conveyor stoppage due to load has been eliminated, and stable operation has become possible.

Third, since the mold is divided into a plurality of sections by a plurality of partitions having a height lower than the surrounding wall in a direction perpendicular to the traveling direction of the conveyor,
The yield of the desired collection product size is improved. In addition, by inclining the middle partition to the rear side, the molten material can easily flow between the adjacent sections easily even in the water with fast solidification, and the yield of the recovered product size is improved.

Fourth, at the overlapping portion of the rear portion of the bottom wall of the mold frame and the front surface of the front partition of the mold frame disposed subsequently to the lower end of the front partition of the subsequent mold frame. The raised bottom wall has a raised shape,
In addition, because of cooling in water, there is almost no leakage of the melt from the overlapping portion, and the specific gravity required for solidification of the melt in which metal and slag are mixed can be sufficiently achieved.

Fifth, since the position where the melt is injected and the back surface of the mold in the vicinity thereof are cooled by a water flow having a flow rate of 1 m / sec or more, the material temperature of the mold does not rise to the melting point, and Since no welding occurs, the release of the solidified material is easily performed.

Sixth, regarding the supply of the molten metal and the slag to the underwater casting conveyor, the molten metal is supplied to an empty mold, and then the slag is supplied. The molten metal on the opening surface is kept warm, and is cooled more slowly than when cooling and solidifying is only water cooling. Therefore, it is ensured that the material having a low specific gravity such as slag mixed in the molten metal floats on the surface of the metal, more completely separate the specific gravity of the slag, and the solidified surface of the upper opening surface of the mold of the molten metal is removed. Smoothness and, in addition, cooling are relatively slow, so that shrinkage due to solidification is sufficiently performed, and a metal lump having few water bubbles and voids inside the metal can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a part of a submerged casting conveyor according to the present invention with respect to a mold part.

FIG. 2 is a perspective view (FIG. 2A) showing the shape of a mold frame for forming the mold shown in FIG.
It is a sectional view by a -C '(Drawing (b)).

FIG. 3 is a view for explaining movements of a mold frame and a conveyor chain in a conveyor head of the underwater casting conveyor shown in FIG. 1;

FIG. 4 is a diagram for explaining movement of the mold frame and the conveyor chain shown in FIG. 3 in more detail;

FIG. 5 is a view for explaining a schematic configuration of a metal recovery apparatus to which the underwater casting conveyor according to the present invention is applied.

FIG. 6 is a view for explaining another example of the underwater casting conveyor according to the present invention.

FIG. 7 is a view for explaining the structure of a cooling water nozzle used for cooling an underwater casting conveyor according to the present invention.

FIG. 8 shows a schematic configuration of a conventional metal recovery apparatus using an underwater casting conveyor (FIG. 8A) and a partially enlarged view thereof (FIG. 8B).

9 is a diagram for explaining movement of a mold and a conveyor chain in a conveyor head portion of the underwater casting conveyor shown in FIG. 8;

FIG. 10 is a perspective view (FIG. 10A) showing the shape of the mold of the underwater casting conveyor shown in FIG. 8, and its line AA ′.
FIG. 5 is a cross-sectional view (FIG. 7B).

FIG. 11 is a diagram showing a state in which a solidified product is injected into a cross section taken along line BB ′ of FIG.

[Explanation of symbols]

 10, 10 'Mold frame 11, 11' partition 13 Conveyor chain 14 Mounting bolt 15 Middle partition 16 Side wall 17 Rising portion 30 Solidified material

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kijo Ueno 5-9-1, Kita Shinagawa, Shinagawa-ku, Tokyo Sumitomo Heavy Industries, Ltd. (72) Inventor Seiji Sugimori 5-2 Sokaicho, Niihama-shi, Ehime No. Sumitomo Heavy Industries, Ltd. Niihama Works (72) Inventor Shigeru Morishita 1850 Minato, Wakayama City, Wakayama Prefecture Sumitomo Metal Industries, Ltd.Wakayama Works (72) Inventor Hiroshi Koide 1850 Minato, Wakayama City, Wakayama Prefecture Sumitomo Metal (72) Yasuhiro Tashiro 1850 Minato, Wakayama City, Wakayama Prefecture Sumitomo Metal Industries, Ltd.Wakayama Steel Works F-term (reference) 3F034 AC01 DA05 DB02 DB07 DD01 EA05

Claims (7)

[Claims] 1. An underwater casting conveyor in which a high-temperature melt containing metal and slag is cast and cooled and solidified in a plurality of molds continuously mounted on an endless conveyor immersed in water. An underwater casting conveyor comprising a front wall and a side wall of a front mold frame and a part of a front wall of a rear mold frame following the front wall. 2. The underwater casting conveyor according to claim 1, wherein the mold frame has a bottom wall, a plurality of side walls, and a front wall on the front side with respect to the traveling direction of the conveyor. The front wall of the rear mold frame following the mold frame, the cross section of the front wall is angled, and one of the front walls is overlapped with the bottom wall of the mold frame immediately before the mold frame. An underwater casting conveyor, wherein a mold frame is fixedly arranged on one conveyor chain. 3. The underwater casting conveyor according to claim 2, wherein the front shape of the front wall of the mold frame is changed from a pin center C1 on the rear side of the conveyor chain to which the mold frame is fixed. An underwater casting conveyor, wherein the conveyor chain has a radius r larger than a distance R to the front surface and has an arc shape centered on a point C2 eccentric below the pin center C1 of the conveyor chain. 4. The underwater casting conveyor according to claim 2, wherein the mold frame is divided by at least one partition in a direction perpendicular to a traveling direction of the conveyor, and the plurality of side walls and the partition are separated from each other. An underwater casting conveyor, which is arranged close to a front wall of a rear mold frame adjacent to the conveyor in the direction of travel of the conveyor, wherein the partition has a lower height than the plurality of side walls. 5. The underwater casting conveyor according to claim 2, wherein the mold frame has a front wall of the rear mold frame at an overlapping portion with a front wall of a rear mold frame following the mold frame. An underwater casting conveyor, wherein a raised portion is provided on the bottom wall adjacent to a lower end of the casting. 6. The underwater casting conveyor according to claim 1, wherein the arrangement of the mold frames is such that the adjacent molds are separated from each other until the solidified material is released from the mold from the position where the hot melt is injected. An underwater casting conveyor characterized in that it can proceed without changing its relative position. 7. The underwater casting conveyor according to claim 1, wherein a cooling means for injecting water having a flow rate of 1 m / sec or more to cool a part of the mold at a position where the high-temperature melt is injected and in the vicinity thereof is provided. An underwater casting conveyor characterized by being provided.