JPH0722818B2 - Metal melting and casting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims to solve the following problems.

(Industrial field of application) The present invention continuously melts various metals, raw materials of various shapes, for example, granular sponge titanium, granular alloy base material, or scraps scraped in the processing process as raw materials, and then The present invention relates to a metal melting and casting apparatus which is capable of continuously solidifying to produce various ingots such as titanium or titanium alloy.

(Prior Art) In the conventional metal melting and casting apparatus, the raw material cut out from the hopper is weighed and divided into a large number, and the divided small portions are successively placed on the belt conveyor 60 as shown in FIG. 21, The conveyor 60 is moved in the direction of the arrow to continuously feed the above-mentioned large number of divided raw materials 61, 61 ... into the melting crucible of the melting chamber, which is the first divided portion cut out from the hopper. Each raw material and each of the later subdivided raw materials are uneven in the size of the raw material particles and the proportion of the alloy component, and each raw material 61 is subdivided by vibration in the process of moving the belt conveyor, etc. 61
.. move to each other, and the mountain becomes large in some parts and becomes small in some parts. When such a material is continuously fed into the melting chamber, the contents of the raw material fed at the beginning and the contents fed at the latter may change, or the time may change as indicated by the chain double-dashed line in Fig. 9. There is a problem that the amount of the raw material fed into the melting chamber fluctuates randomly with the passage of time. Such a large fluctuation causes unevenness in the melting of the raw materials in the melting chamber, and as a result, there is a defect that the ingot obtained by solidifying the melted raw material becomes coarse and dense. Further, in the case of manufacturing an alloy ingot, when the raw materials classified as described above are mixed with each other on the conveyer, a variation occurs in the mixing ratio of the raw materials at the place, resulting in that In the ingot obtained by melting and solidifying, there is also a defect that segregation of components occurs.

There is also known one in which the raw material is supplied by a feeder such as a slide (for example, JP-A-57-97863).
(See the official gazette). However, such a structure also has many problems similar to those of the conventional belt conveyor.

Further, the tubular body is fixed in a horizontal state, the rotary shaft is arranged around this internal shaft, the spiral blade is fixed around the shaft, and the rotary shaft is rotated to rotate the raw material in the cylinder in the axial direction. There are also known technical matters relating to screw feeders that are pushed forward (for example, Japanese Patent Laid-Open No. 58-17006 and Japanese Utility Model Laid-Open No. 58-1).
See each publication of No. 87526).

However, the screw-type feeder described above is "a cylindrical body is fixed and the internal spiral blades rotate". Therefore, firstly, it is suitable for transferring powder and fine powder, but it is a relatively large raw material. , A raw material containing a crushed piece of lump, the inner surface of the cylinder,
And the outer edge of the spiral blade to stop the rotation of the spiral blade to make the transfer difficult.

Secondly, the raw material is pushed forward in a pressing (compressing) state in the cylinder core direction by the spiral blade. Therefore, when different kinds of raw materials are charged at the same time in succession, there is also a problem that they proceed without being mixed (without being mixed) and are sent out in the order of charging. There is a problem that deteriorates the property.

(Problems to be Solved by the Invention) In the present invention, except for the above-mentioned conventional problems, firstly, different raw materials that are sent one after another at different times do not mix with each other,
It can be continuously transferred in a separated state. Secondly, sufficient mixing is performed in the process of feeding a plurality of heterogeneous raw materials that have been fed almost simultaneously, and thirdly, even if the raw material is granular. Even if it is a crushed piece, it can be sent out in a flowing state along with the peripheral surface of the cylindrical body as it is by using its own weight without compressing it. Fourthly, the raw material is fed to the melting chamber. When sending out,
For example, a non-oxidizing atmosphere and communication with the atmosphere when receiving raw materials can be alternately performed.
In addition, on the melting chamber side, the raw materials can be continuously received in a switchable manner, for example, from the transporting means composed of a plurality of cylindrical bodies in a non-oxidizing atmosphere.

By providing a transporting means for a metal melting and casting apparatus having many excellent characteristics, a good quality ingot can be produced in a melting chamber, and as a result, a high quality ingot with less coarse and dense and less segregation of components. It is an object of the present invention to provide a metal melting and casting apparatus capable of obtaining the above.

The configuration of the present invention is as follows.

(Means for Solving Problems) The invention of the present application employs means as described in the claims, and its operation is as follows.

(Operation) The raw material cut out from the raw material cutting means enters the cylindrical body through the raw material receiving port. The raw material contained in the tubular body moves toward the raw material delivery port along the spiral raw material passage formed on the inner surface of the peripheral wall of the tubular body along with the rotation of the tubular body,
It is delivered from the raw material delivery port.

(Example) Hereinafter, drawings showing an example of the present application will be described. In FIG. 1, the melting and casting apparatus, as shown in FIG. 1, is a raw material supply facility A, a plasma melting apparatus B,
And a casting apparatus C. First, in the raw material supply facility A, the bucket conveyor 11 has 13 buckets 12, and the raw material weighed by a weighing device (not shown) is received in the bucket 12 and then conveyed to the hopper 13 above. . The weighing device is composed of a combination of a storage hopper and an electromagnetic feeder separately provided for the particle size and type of raw material,
For example, titanium and two types of alloy base materials are cut out from their respective storage hoppers by their respective electromagnetic feeders, and each load cell is weighed in small units of 20 kg in total so that a predetermined mixing ratio is achieved. The raw material that weighed is 3
The brands are mixed and cut out at one place on the belt conveyor,
It is conveyed on the floor surface and guided to one of the buckets 12 on the bucket conveyor 11. After 20 kg is stored in one bucket, weigh the above again and carry out the next 20
Guide kg to the next bucket of the bucket on the bucket conveyor 11. Repeat this process and store 20 kg in each of the 13 buckets. In the present specification,
The weighing device, belt conveyor and bucket conveyor 11
The part consisting of is called a measuring and cutting means. A drum feeder 15 used as a conveying means is provided on a frame 14 constructed next to the conveyor. The two drum feeders 15 are provided side by side in parallel (the other one is hidden behind the one shown in FIG. 1). A charging port 16 is provided at one end of each drum feeder 15 so that the raw material can be received from the hopper 13. Further, the hopper 13 is located above the bucket conveyor so as to receive the total amount of the raw materials dropped by the turning of the bucket which is turned when the bucket conveyor is driven by one bucket. The charging port 16 of the drum feeder is closed by a door when the raw material is not charged. A chute 17 is connected to the other end of the drum feeder 15.

Next, in the plasma melting apparatus B, a melting chamber 20 is fixed to the frame 14 at a position below the drum feeder 15. A raw material charging section 21 is provided at the center of the upper portion of the melting chamber 20, and the chute 17 is in communication therewith. Six plasma torches 24 are attached to the melting chamber 20 around the charging portion 21.

Next, the casting apparatus C has an ingot chamber 36. A crucible 37 is provided in the upper part of the ingot chamber 36, and the crucible 37 is fitted in a through hole formed in the lower part of the melting chamber 20. As is well known, the crucible 37 forms a molten metal pool therein. An ingot lowering device 38 is provided inside the ingot chamber 36. The pull-down device 38 has a multi-stage cylinder. A stub clamp 39 is provided at the upper end of the pulling device 38,
Inside the crucible 37, there is attached a stub 40 which forms the bottom of the crucible.

In the above configuration, when the raw materials are successively supplied from the measuring and cutting means to the drum feeder 15, the supplied raw materials are sequentially sent to the chute 17 side by the feeder 15, and the melting chamber is passed through the chute 17. Sent to 20. In the melting chamber 20, the raw material is dropped into the crucible 37 through the charging section 21. Then, the raw material is heated by the plasma arc emitted from the plasma torch 24 and melted to become a molten metal. Supply of raw materials to the pot and torch 24
The melting of the raw material is carried out continuously. Then, as the amount of molten metal increases, the stub 40 is pulled down by the pulling device 38, and the molten metal located in the lower part inside the crucible 37 is sequentially solidified into an ingot, which is sequentially drawn out downward from the crucible 37. To be done.

Next, the drum feeder 15 will be described in detail with reference to FIGS. The hollow casing 41 is configured so as to be hermetically sealed so as to be shielded from the outside air, and has a raw material inlet 42 at one end and a connection port 43 to the chute 17 at the other end. Inside the casing 41, a cylindrical tubular body 44 is rotatably provided. The tubular body 44 is supported by three support rollers 47 at two places indicated by reference numerals 45 and 46, respectively. A contact plate 48 is provided around the cylindrical body 44, and a support roller 47 is in contact with the contact plate 48. The tubular body 44 is provided with an inner collar-shaped collar 49 on the inlet side of the casing 41, and the inside thereof is the raw material inlet 50. On the other hand, the other end of the cylindrical body 44 is open and serves as a raw material delivery port 51. Partition walls 52 are spirally attached to the inner surface of the peripheral wall of the cylindrical body 44, and a spiral raw material passage 53 is formed along the inner surface of the cylindrical body 44 between adjacent partition walls 52. . The partition wall 52 is an example
It has 13 pitches. It should be noted that the number of the raw materials in one section fed from the receiving port 50 is changed by the rotation of the tubular body 44.
It suffices that the number of pitches allows sufficient mixing until reaching the delivery port 51 by 53, and it may be less than the above 13. Further, the height of the partition wall 52 is preferably set so that the raw material of each section put in the raw material passage 53 does not get over the wall 52 and move to another. It should be determined according to the amount, the diameter of the tubular body 44, and the like. As an example, when the diameter of the cylindrical body 44 is about 1100 mm, the raw material for one section is about 20 kg, and the size of one pitch is 225 mm,
The height of the partition wall 52 is, for example, about 300 mm. With this size, scraps up to 80 mm cube can be smoothly transported. Further, although the cylindrical body 44 is arranged in a substantially horizontal state in this example, it may be inclined within a range of up to about 5 ° so that the side of the delivery port 51 becomes higher.

In the case of the above configuration, when charging the raw material into the raw material inlet 50, first, the bucket conveyor is driven by one bucket so that the total amount of the raw material in one section is moved to the portion of the raw material passage 53 located closest to the raw material inlet 50. Charge. Next, the cylindrical body 44 is rotated 360 degrees, and the above-mentioned one section of raw material is delivered along the passage 53.
Move forward one pitch to side 51. Then, in that state, the bucket conveyor is driven again by one bucket in the same manner as above, and the entire amount of the raw material of the next one section is charged. In the same manner, the divided raw materials are successively charged by the number of pitches of the partition wall while repeating the forward movement of the raw material by one pitch.

Next, when the raw material is delivered toward the melting chamber 20, the cylindrical body 44 is continuously rotated in a state where the charging port 42 is closed and the inside of the casing is replaced with a non-oxidizing atmosphere such as argon,
The raw material is delivered from the raw material delivery port 51 toward the connection port 43. While the melting by one drum feeder is in progress, operate the weighing and cutting device and the bucket conveyor, load the raw material into the other drum feeder, and switch when the raw material of the previously used drum feeder is supplied. This is repeated to continuously supply all the raw materials necessary for melting.

Next, the state of feeding the raw material while rotating the cylindrical body 44 as described above will be described with reference to FIGS. 4 to 8. In these figures, (A) shows the cylindrical body 44 as a delivery port.
The state viewed from the side of 51 is shown, and (B) shows the state where the tubular body 44 in each state is cut at the uppermost position and expanded. Each divided raw material 55 contained in the raw material passage 53 is rotated by the rotation of the tubular body 44 as shown by the arrow.
It is repeatedly lifted by the inner wall surface of the tubular body 44, moved upward, and then collapsed downward. By repeating this, each divided raw material 55 is sequentially moved to the delivery port 51 side along the spiral raw material passage 53. Then, in the process, each of the divided raw materials is sufficiently mixed. In FIG. 4 (B), reference numeral 56 shows contour lines of the raw material 55 for one section in the raw material passage 53. As described above, when the divided raw materials 55 move to the delivery port 51 by the rotation of the tubular body 44, the dividing wall
At the time when the end 52a of 52 passes the lowermost position as shown in FIG.
From the state shown in FIG. 4 to the state in which the cylindrical body 44 has rotated about 90 degrees, that is, the state shown in FIG. Resulting in. Then, as shown in FIG. 6, from the state of FIG.
Almost all of the divided raw materials of the above-mentioned one division fall from the delivery port 51 at the time when the rotation is about 180 degrees. After that, the state shown in FIG. 8 is passed through the state shown in FIG. That is, a state similar to that shown in FIG. By repeating such operations one after another, the divided raw materials are sequentially supplied to the melting chamber from the delivery port 51 without intermingling with each other. If this state is shown in a graph, the state shown by the solid line in FIG. 9 is obtained. That is, with the passage of time, a constant amount of raw material is delivered at regular intervals. As a result, in the melting chamber, the supply amount of the raw material does not change between the beginning and the end of the melting, so that the amount of the raw material is not too large or too small. Therefore, even in the ingot obtained in the casting apparatus C, a large density cannot be achieved.

In the above case, if the tubular body 44 is inclined so that the side of the delivery port 51 becomes higher, the delivery port 51 accompanying the rotation of the tubular body 44
It is possible to feed out a single section of the raw material from the above in small steps over a relatively long time period of one rotation of the tubular body 44. As a result, the fluctuation of the amount of raw material in the melting chamber can be further reduced, and the density of the ingot can be further reduced.

Next, FIGS. 10 to 14 show examples in which the partition walls are arranged differently. In the example shown here, the spiral of the partition wall 52e is made slightly larger in the vicinity of the raw material delivery port 51e, and the width of the raw material passage 53e is gradually increased in the vicinity of the delivery port 51e. By gradually increasing the width of the raw material passage 53e in this manner, the cylindrical body 44 near the raw material delivery port is formed.
The rapid collapse of the raw material 55e due to the rotation of the can be prevented.
As shown in FIGS. 14 to 14, the raw material 55e of one section can be continuously and gradually delivered over the entire process of one rotation of the tubular body 44e, and it can be continued over a large number of section raw materials. That is, as shown in FIG. 15, a constant amount of the raw material can be constantly supplied to the melting chamber over time. As a result, the supply amount of the raw material is always constant in the melting chamber, and the whole ingot formed in the casting apparatus has a uniform density. That is, an ingot without segregation can be obtained. It should be noted that the section W in which the spiral of the partition wall 52e is increased is within a range corresponding to a quarter rotation of the cylindrical body 44e, and the degree of the spiral of the partition wall 52e at that point is It will be about twice as large as other places. However, the extent of increasing the advance of the spiral in the above range W or at that location depends on the amount of raw material in one section, the size of the tubular body 44e, the height and pitch of the partition wall 52e, and the tubular body 44e.
It is preferable to experimentally determine in accordance with the rotation speed of the. That is, as described above, it is preferable that the raw material of one section is gradually and continuously delivered from the delivery port 51e over the entire process of one rotation of the cylindrical body 44e.

In addition, parts that are considered to be the same or equivalent in configuration to those in the previous figure in terms of function are denoted by the same reference numerals as those in the previous figure with the letter e added to omit redundant description. (Also in the following drawings, the alphabets f, g, and h are added in order based on the same idea in order to omit redundant description.) Next, in FIGS. 16 to 18, the cylindrical shape near the delivery port is shown. An example is shown in which the shape of the body is made different from that described above, and the width of the raw material passage there is widened. That is, the partition wall
The length of the tubular body 44f is made slightly longer at the end portion 52af of the 52f, and a protruding portion 56 further protruding from the end portion 52af is provided. By doing so, the raw material can be continuously fed little by little over the entire process of one rotation of the cylindrical body 44f, as in the above embodiment. The overhanging dimension of the overhanging portion 56 is about half of the spiral pitch of the partition wall 52f, but the size may be experimentally determined as in the case of the above-described embodiment.

Next, FIG. 19 shows an example in which the height of the partition wall 52g is gradually reduced in the vicinity of the outlet 51g. By doing so, the raw material can be continuously delivered little by little as in the case described above. The height of the end portion 52ag of the partition wall 52g is formed to be, for example, about 1/4 of the height of the other portions, and the range W'where the height of the partition wall 52g is successively lowered is, for example, 180 degrees or It is set in the range of 270 degrees. However, as described above, the degree to which the height of the partition wall is gradually lowered and the range thereof should be determined experimentally as in the above case. For example, a range of about 90 degrees indicated by W ″ in FIG. 19 (A). It is preferable that the divided raw material is set so as to get over the partition wall 52g in that range.

Next, FIG. 20 shows a further different example of the structure near the delivery port. In this example, the push plate 57 is provided at a position one pitch before the end 52ah of the partition wall. In addition, the degree of inclination of the push plate 57 (the degree of inclination in the rotation direction) is set to an intermediate level between the portion 52′h in which the inclination (progress of the spiral) of the partition wall 52h is large and the other portions. is there.

With this configuration, it is possible to prevent the peaks of the raw material in one section from collapsing and spreading too much in the vicinity of the delivery port 51h, thereby further reducing the peak of the raw material delivery amount per one rotation of the tubular body 44h. You can

To prevent the sudden collapse of the raw material 55 near the raw material delivery port,
The effect is also exhibited when the side of the delivery port 51 is raised and the cylindrical body 44 is inclined by about 5 °. Therefore, in any of the methods shown in FIGS. 10 to 20, the peak of the raw material delivery amount can be further reduced by inclining the tubular body 44.

(Effect of the invention) As described above, in the present invention, the raw material is weighed in small portions by the measuring and cutting means, and the weighed subdivided raw material 55 is delivered to the tubular body 44 as it is, and the inner peripheral wall of the tubular body 44. With respect to the melting chamber 20 through the spirally arranged raw material passage, the first point is that one section of raw material once weighed and entered into the raw material passage does not mix with other raw materials, The cylindrical body 44 has a feature that it advances in a column shape in the cylinder center direction. This means that the raw material properties of each raw material (mixing ratio of multiple raw materials) do not change the raw material properties by partially mixing with other raw materials. There is an effect that can be made.

As a second point, the raw materials for each section are each provided with an inner surface (concave curved surface) of the tubular body 44 in the raw material passage 53 in a direction intersecting with the cylinder center.
Therefore, the mixing effect with respect to each of the divided raw materials is great, and the excellent effect of homogenizing the hot water in the next stage is brought about.

Thirdly, the tubular body rotates. The spiral partition wall is fixed to and integrated with the inner surface of the tubular body. Therefore, regardless of whether the raw material is granules or crushed pieces, there is no fear of biting into the inside of the tubular body, and there is also an effect of moving along the inner surface of the tubular body in a natural state and delivering.

Fourthly, the supply of the raw material from the plurality of tubular bodies to the melting chamber has the effect that it can be delivered under an adapted atmosphere at the time of each supply, and when the raw material is supplied to the melting chamber by one tubular body, Others are effective in maintaining the continuity of the entire melting operation, such as being able to receive raw materials from the metering and cutting means.

Furthermore, in the present invention, the raw material passage 53e in the tubular body 44e is replaced by the raw material passage 53e in the raw material delivery port 51e.
The width of the raw material passage 53e of the raw material delivery port 51e is made wide so that the raw material 55e of one section passing through the 53e and appearing at the delivery port 51e is delivered little by little by the rotation of the cylindrical body 44e at the raw material delivery port. Alternatively, by forming the height of the partition wall 52g forming the raw material passage to be low, the raw materials addressed to the one section do not collectively go to the melting chamber 20,
It is poured out in a scattered and small amount over a relatively long time within the rotation time range, and exhibits an excellent effect of facilitating the dissolution in the dissolution chamber 20.

[Brief description of drawings]

The drawings show the embodiments of the present application. FIG. 1 is a schematic vertical sectional view of a melting and casting apparatus, FIG. 2 is a partially cutaway front view of a drum feeder, and FIG. 3 is only a casing of the drum feeder. Diagrams broken away at line III, FIGS. 4 to 8
FIG. 9 is a diagram for explaining the operation, FIG. 9 is a graph showing the relationship between the passage of time and the amount of raw material delivered, and FIGS. 10 to 14 are diagrams for explaining the operation of different embodiments (corresponding to FIGS. Figure), No.
FIG. 15 is a graph showing the relationship between the passage of time and the amount of raw material delivery in what is shown in FIGS. 10 to 14, and FIG. 16 is a view showing a further different embodiment of the tubular body, FIG. 17 and Figure 18 shows
FIG. 16 is a plan view and a right side view, respectively, of FIGS. 16A and 16B, and FIGS. 19 and 20 are views showing further different embodiments of the tubular body, respectively.
FIG. 21 is a schematic view of a conventional conveying means. 44 …… Cylindrical body, 50 …… Raw material inlet, 51 …… Raw material outlet,
52 …… compartment wall, 53 …… raw material passage, 55 …… raw material.

Claims (4)

[Claims] 1. A measuring / cutting-out means adapted to deliver a fixed amount of raw material to the next stage, and a raw material being received from said measuring / cutting-out means and transferred to the melting chamber of the next stage. In a metal melting and casting apparatus provided with a conveying means and a melting chamber for converting the raw material fed from the conveying means into a molten metal for casting, the conveying means comprises at least two hollow hollow structures having a closed structure capable of blocking the outside air. A casing is provided, and a raw material inlet for receiving the raw material from the measuring and cutting means is provided at one end of each casing, and a connection port connected to a hollow chute communicating with the melting chamber is provided at each other end. Each of the casings is further provided with the raw material inlet at one end facing the charging inlet side, the raw material feeding outlet at the other end facing the connection opening side, and the cylinder core is rotated in a horizontal state. Rotate as the center Each of the hollow cylindrical bodies arranged as described above is arranged on the inner surface of the peripheral wall of each of the cylindrical bodies, and the raw material introduced from the raw material receiving port at one end through the charging port causes rotation of the cylindrical body. Along with the inner surface of the peripheral wall, the inner wall is relatively moved in the circumferential direction toward the raw material delivery port at the other end so that the partition wall is fixed spirally to form a spiral raw material passage on the inner surface of the cylindrical body. A metal melting and casting device characterized by being formed. 2. A measuring / cutting-out means for sending a fixed amount of the raw material to the next stage, and a raw material from the measuring / cutting-out means for transferring the raw material to the melting chamber of the next stage. In a metal melting and casting apparatus provided with a conveying means and a melting chamber for converting the raw material fed from the conveying means into a molten metal for casting, the conveying means comprises at least two hollow hollow structures having a closed structure capable of blocking the outside air. A casing is provided, and a raw material inlet for receiving the raw material from the measuring and cutting means is provided at one end of each casing, and a connection port connected to a hollow chute communicating with the melting chamber is provided at each other end. Each of the casings is further provided with the raw material inlet at one end facing the charging inlet side, the raw material feeding outlet at the other end facing the connection opening side, and the cylinder core is rotated in a horizontal state. Rotate as the center Each of the hollow cylindrical bodies arranged as described above is arranged on the inner surface of the peripheral wall of each of the cylindrical bodies, and the raw material introduced from the raw material receiving port at one end through the charging port causes rotation of the cylindrical body. Along with the inner surface of the peripheral wall, the inner wall is relatively moved in the circumferential direction toward the raw material delivery port at the other end so that the partition wall is fixed spirally to form a spiral raw material passage on the inner surface of the cylindrical body. In addition, the raw material passage in the tubular body is formed in the raw material delivery port by passing through the raw material passage in the tubular body and appearing in the delivery port. A metal melting and casting apparatus, characterized in that the raw material passage has a wide raw material passage width so that the raw material can be delivered little by little, or the height of a partition wall forming the raw material passage is low. 3. The metal melting and casting apparatus according to claim 1 or 2, wherein the measuring and cutting means comprises a weighing device, a belt conveyor and a bucket conveyor. 4. The metal melting and casting apparatus according to claim 1 or 2, wherein the cylindrical body is inclined so that the side of the raw material delivery port is raised.