JPH0798265B2 - Method and apparatus for manufacturing ingot - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an ingot having a dense composition by solidifying while applying a high pressure, which is called a high strength material, and an apparatus therefor. In particular, it is a new proposal regarding a pressure casting method and an apparatus therefor using an electromagnetic pump.

[0002]

2. Description of the Related Art Conventionally, a casting method using an electromagnetic pump has been generally known. For example, Japanese Patent Application Laid-Open No. 61-129267 proposes a uniform pressure type casting apparatus utilizing electromagnetic force, and Japanese Patent Application Laid-Open No. 63-58.
In JP 61, an example is proposed in which an electromagnetic pump is used as a means for transferring the molten metal to the mold cavity.
However, most of these technologies were considered in consideration of being applied to a device for producing a small-sized and relatively thin-walled cast product, and additionally, the force of an electromagnetic pump is used as an auxiliary. In most cases Because the device described in the former publication is
As is clear from the figure, it is premised that the molten metal is used to inject into the mold using its own weight, and the device described in the latter publication is the pressure applied to the molten metal in the final mold cavity. Is assumed to be obtained by the plunger.

Conventionally, in the case of making a relatively large ingot, most of the methods are continuous casting. Needless to say, continuous casting is a method in which molten metal is introduced into a belt wrapper or the like while being guided by rollers, and the surroundings are forcibly cooled and drawn downward to form an ingot. In this continuous casting production method, the pressure at the time of solidification of the molten metal is only due to its own weight, and the depth of the molten metal is at most about 20 cm, so it is impossible to solidify while applying sufficient pressure.

When a high-strength material is cast as an ingot, it is necessary to cool and solidify the molten metal while applying a high pressure before the solidification. In addition, casting by pressurization is an important technique to prevent the formation of cavities inside the ingot when it is completed. On the other hand, when pouring the molten metal into the mold, it is required to fill the molten metal from below the mold at a low speed and with a low pressure so that the molten metal surface does not dance. Heretofore, a casting method and its apparatus capable of satisfying such contradictory workability have not been proposed.

Although there is a pressure type or suction type casting method using gas, the former pressure type method requires the preparation of a melting furnace having a strength capable of withstanding the pressure, and Since the expansion coefficient is large, it is difficult to control the pressure fluctuation during operation, especially when cooling and solidifying the ingot by a numerical value for the purpose. In the latter case of the suction type, the pressure applied to the molten metal during solidification is only due to its own weight, and it cannot be expected to apply a large pressure to the ingot as in the continuous casting method described above.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, enables pressurization conditions during solidification, and enables low-pressure low-speed pouring when filling a mold with molten metal. The present invention has been invented for the purpose of providing an optimal ingot production method for producing ingots and an apparatus therefor.

[0007]

[Means for Solving the Problems] That is, in order to achieve the above-mentioned object, the present invention sends a molten metal in a melting furnace into a mold using an electromagnetic pump, and cools and solidifies it while pressurizing it to form an ingot. In the manufacturing method, while gradually increasing the output of the electromagnetic pump, the molten metal is supplied into the mold, and the output of the electromagnetic pump is further increased from the state where the molten metal is filled in the mold to add the molten metal in the mold. We propose a method for producing an ingot, which comprises pressing and cooling the mold while maintaining the pressurization state to solidify the molten metal in the mold.

Further, in the present invention, a melting furnace for melting the molten metal , a mold having an inner chamber for molding the ingot therein, a cooler for cooling the inner chamber of the mold, and the molten metal discharged from the melting furnace. In an ingot manufacturing apparatus having an electromagnetic pump and a connecting pipe for guiding the molten metal from the discharge port of the electromagnetic pump to the bottom of the mold, a detecting means for detecting that the inner chamber of the mold is filled with the molten metal, The valve 12 that opens and closes the upper portion of the inner chamber and the detection unit detects that the inner chamber of the mold is filled with the molten metal, so that the valve 12 is closed and the output of the electromagnetic pump is maintained at a high output. And a controller for operating a cooler, and an ingot manufacturing apparatus is proposed.

In this case, the inner chamber of the mold is filled with the molten metal.
The inner chamber of the mold is the detection means for detecting the filling
A level meter can be used to detect the level of molten metal injected into the
Wear. In addition, as the detection means, it is provided at the top of the mold.
It is also possible to use a sensor for detecting molten metal.

[0010]

The operation of the ingot according to the present invention having the above structure
According to the manufacturing method, the electromagnetic pump fills the inner chamber of the mold with molten metal.
In doing so, gradually increasing the output of the electromagnetic pump
Since the molten metal is poured into the mold, the molten metal is rapidly poured into the mold.
Will not be trapped in the molten metal and will cause porosity.
It can be prevented. Furthermore, the molten metal was completely filled in the mold.
After that, maintain the output of the electromagnetic pump at a high output and
As the hot water is pressurized while being solidified, it has a precise internal structure.
A woven ingot can be stably manufactured. Furthermore
In the ingot manufacturing apparatus according to the present invention, the above-described manufacturing method
Can be performed automatically with simple components
The device can be excellent in safety and safety.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing an ingot according to the present invention and an apparatus for carrying out the method will be described below with reference to the drawings. FIG. 1 shows the overall configuration of an apparatus to which the method of the present invention is applied. In the figure, 1 is a melting furnace, and a molten metal 2 is inside.
Is stored. 3 is an electromagnetic pump. Reference numeral 4 is a connecting pipe for supplying molten metal to the mold 5 from the discharge port of the electromagnetic pump 3. Reference numeral 6 is an inner chamber capable of forming an ingot, and 7 is a cooler . The molten metal 2 is sucked by the electromagnetic pump 3, passes through the connection pipe 4 from the discharge port, is supplied into the mold 5, and finally an ingot is manufactured.

Reference numeral 8 denotes a pipe which is branched in the middle of the above-mentioned connecting pipe 4 and extends upright so that a level meter 9 is formed inside the pipe and the valve 1 which can be opened at the top.
A pressure gauge 11 with 0 is constructed. On the other hand, a valve 1 capable of opening the inner chamber 6 of the mold at the top of the mold 5 described above.
There are two. The height of the extension pipe 8 is almost equal to that of the inner chamber 6 of the mold 5.
It is constructed to a position slightly higher than the top of the
It is necessary that the level of the molten metal 2 injected inside does not exceed the position where the valve 10 provided on the extension pipe 8 side, that is, the pressure gauge 11 is attached. Level meter 9
Is in the extension tube 8 and constantly monitors the level of the molten metal.
For this reason, the molten metal 2 flowing into the extension pipe 8 is devised so as not to solidify there. For that purpose, it is necessary to constantly heat the periphery of the extension tube 8 to a temperature at which the molten metal 2 does not solidify or to maintain a perfect heat retention state during the casting operation. Reference numeral 13 is a controller. The controller 13 controls the electromagnetic pump 3, the level gauge 9, the pressure gauge 11, and the valves 10 and 12. This control will be described later.

A method of manufacturing an ingot by the present apparatus having this type and structure will be described below with reference to FIGS. 2 and 3. Figure 3
[Fig. 4] is a graph showing how the output of the electromagnetic pump 3 is executed with time in the device of the present invention.
The molten metal 2 is stored in the melting furnace 1, and the electromagnetic pump 3
Although it is sucked by (not shown), at the start of the casting operation, the output of the electromagnetic pump (that is, supply current value, hereinafter referred to as current) is at point A shown in FIG. That is, the current is zero. In addition, prior to the operation of the electromagnetic pump,
The valves 10 and 12 are opened so as to communicate with the outside air, and the cooler 7 formed on the outer periphery of the mold 5 is in a stopped state.

The electromagnetic pump supplied with the electric current applies an electromagnetic force proportional to the electric current value to the molten metal forming the secondary side.
Therefore, the molten metal flows into the connecting pipe, and its flow is the mold 5
Flows into the inner chamber 6 of. The current value of the inflow speed at this time is controlled so that the molten metal can be slowly injected into the inner chamber 6. At the same time, the molten metal is an extension pipe 8
It also flows into the inside, and the level meter 9 outputs an output proportional to the amount of the inflow to inform the amount of the molten metal in the inner chamber 6 of the mold 5.
By controlling as described above, the dance of the molten metal can be suppressed, and since the molten metal that has flowed into the mold 5 does not entrain the gas that causes the porosity, a dense composition is maintained,
The inner chamber 6 is filled with the molten metal.

The electromagnetic pump increases its current value over time. The rate of increase is proportional to the amount of molten metal supplied to the mold. The reason is that the melt itself has a weight, and in order to feed the melt into the mold while maintaining the same speed, it is necessary to add a counter pressure amount due to the weight. Eventually, the molten metal fills the mold and reaches the top of the inner chamber 6. This state is determined by monitoring the instruction of the level meter 9. That point is point B shown in the graph of FIG. When the operation has reached this point, the control for closing the valves 10 and 12 is performed as the next work procedure. Valves 10, 12
When is closed, the inner chamber 6 of the mold 5 and the inside of the extension pipe 8 are sealed. The electromagnetic pump is controlled so that the molten metal is supplied to the mold with the maximum output current after confirming that the valves 10 and 12 are closed. As a result, the pressure in the mold rises and reaches the pressure peak point shown in the graph. This pressurization situation is displayed by the pressure gauge 11 provided with the valve 10,
The operator can control the control current of the electromagnetic pump based on the display. Then, when the pressure gauge has reached the target value, the cooling medium is controlled to pass through the cooler 7 to start cooling the molten metal in the mold. At this time, the output of the electromagnetic pump is such that a force necessary to maintain the pressure in the mold is produced, and the electromagnetic force and the applied pressure are in a balanced state. As a result, the molten metal starts to solidify from the surroundings while maintaining a sufficiently pressurized state, and becomes an ingot while maintaining the condition as a high strength material.

Incidentally, as described above, it is not preferable that the molten metal in the connecting pipe 4 and the extension pipe 8 is solidified during this work. For that purpose, a separate heating means 20 will be required to prevent the molten metal from solidifying in the vicinity of the molten metal injection port. Most, for example, when the metal to be cast is aluminum, the heating means described above is not required, and it is possible to prevent solidification sufficiently by simply performing heat retention. When the solidification is completed by cooling, the operation of the electromagnetic pump is terminated, and the molten metal remaining in the connecting pipe 4 and the extension pipe 8 is returned to the melting furnace 1 and completed. Point C in the graph represents the time point.

The work procedure described above can be treated as a series of automated controls by the controller 13 already described above. That is, the control of the electromagnetic pump is the control of the current value given to the electromagnetic pump, the indication of the level gauge and the pressure gauge is the display output of the instrument, and the opening / closing operation of the valve is performed electrically by using the solenoid valve. It is possible to operate. If the construction of the entire apparatus is completed while taking such technical measures, the ingot manufacturing method according to the present invention can easily achieve automation.

FIGS. 4 and 5 are an apparatus configuration diagram and a partially enlarged view for explaining another embodiment of the present invention. The reference numeral is FIG.
The same components as those used in the above are used as they are for the description. Generally, the current level meter 9 has been put into practical use only when the measuring length is about 50 cm. However, there are many large ingots required as products that exceed the limit of the level meter. In such a case, the demand can be met by the device of the present invention having the structure described below. The apparatus of FIG. 4 comprises a sensor 22 capable of detecting the arrival of the molten metal at a valve 12 formed at the top of the mold 5 having a top higher than the measurement range of the level meter 9. That is, as shown in the example in FIG. 5, a recess 23 for mounting a sensor is formed on the top of the inner chamber 6 of the mold 5, and the sensor 24 and the communication pipe 25 for the valve 12 are formed in the recess 23. Specifically, as a result of using a spark plug for an automobile as this sensor, a result that can sufficiently achieve the purpose was obtained.

The operation when the sensor 22 of this kind is incorporated is slightly different from the operation procedure of the apparatus of the present invention described in FIG. Specifically, as the molten metal 2 flowing into the mold rises above the molten metal surface, it rises to a state where it exceeds the measurement range of the level meter 9, so that the valve 10 provided in the extension pipe 8 before that rises. It is closed when the measured value of the level meter 9 reaches a value regulated in advance. At this time, the valve 12 provided on the side of the other inner chamber 6 is still in the open state. as a result,
The extension pipe 8 is hermetically sealed while a certain amount of gas remains, and even if the molten metal 2 is subsequently supplied into the mold 5, the molten metal in the inner chamber 6 rises. The level rise beyond the compression does not occur, the level gauge 9 does not shake off, and the molten metal does not flow into the pressure gauge 10. Instead, the molten metal surface rising in the inner chamber 6 senses the time when the molten metal is filled when it comes into contact with the sensor 22, so the valve 12 is immediately closed with the output display, and thereafter. The control from point B shown in the graph of FIG. 3 may be performed. It should be noted that the operation described above can be automated in this embodiment as well, and there is no work procedure that hinders automation of a series of operations.

[0020]

INDUSTRIAL APPLICABILITY The method and apparatus for producing an ingot according to the present invention make full use of the characteristics of an electromagnetic pump, and a casting method for always stably producing an ingot having a dense composition as a high-strength material. Exert its effect as. That is, in order to prevent the occurrence of porosity required for the high-strength material, the molten metal is supplied to the mold at a low speed and at a low pressure to sufficiently prevent the problem of the molten metal from dancing. is doing. Furthermore, after the mold is filled with the molten metal, the pressure required to densify the composition of the molten metal is obtained by controlling the exciting current of the electromagnetic pump, so at least in comparison with conventional continuous casting, it is sufficient. Pressure can be applied.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an ingot manufacturing apparatus of the present invention.

FIG. 2 is a schematic configuration diagram for explaining a method for manufacturing an ingot according to the present invention.

FIG. 3 is a graph for explaining control characteristics of the electromagnetic pump according to the present invention.

FIG. 4 is a configuration diagram of an ingot manufacturing apparatus for explaining another embodiment of the present invention.

5 is an example of a sensor applied to the example of FIG. 4. FIG.

[Explanation of symbols]

1 Melting Furnace 3 Electromagnetic Pump 4 Connection Pipe 5 Mold Cavity 7 Cooler 8 Extension Pipe 9 Level Meter 11 Pressure Gauge 10, 12 Valve 13 Controller 22 Sensor

Claims (4)

[Claims] 1. A method for producing molten metal in a melting furnace by using an electromagnetic pump to feed the molten metal into a mold, cooling and solidifying the molten metal while pressurizing the molten metal, and gradually increasing the output of the electromagnetic pump.
While feeding, the molten metal is supplied into the mold, and the molten metal fills the mold.
The output of the electromagnetic pump from the
Pressurizes the melt in the mold and casts while maintaining the pressurized state.
A method for producing an ingot, which comprises cooling a mold and solidifying a molten metal therein . 2. A melting furnace for melting the molten metal , a mold having an inner chamber for molding an ingot, a cooler for cooling the inner chamber of the mold, and an electromagnetic pump for discharging the molten metal from the melting furnace. In the ingot manufacturing apparatus having a connecting pipe for guiding the molten metal from the discharge port of the electromagnetic pump to the bottom of the mold, a detection means for detecting that the molten metal is filled in the inner chamber of the mold, and the inner chamber of the mold A valve 12 that opens and closes the upper part and the detection means detects that the inner chamber of the mold is filled with the molten metal, so that the valve 12 is closed and the output of the electromagnetic pump is maintained at a high output and the cooling is performed. And a controller for operating the vessel. 3. The mold according to claim 2, which is melted in the inner chamber of the mold.
The detection means that detects the filling of hot water is the inner chamber of the mold.
An ingot manufacturing apparatus, which is a level meter for detecting the level of molten metal injected into a container . 4. The mold according to claim 2 , which is melted in the inner chamber of the mold.
The detection means that detects the filling of hot water is the upper part of the mold.
An ingot manufacturing apparatus comprising a sensor for detecting a molten metal provided in the .