JP2004108725A - Pressurization induction melting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressurization induction melting device capable of preventing a water cooled cable connecting an induction coil in a melting furnace incorporated in a pressure vessel with external power supply from being deformed even when pressurizing it and circulating cooling water inside the device securely. <P>SOLUTION: This pressurization induction melting device 1 comprises a pressure vessel 2 capable of being tightly closed, an induction melting furnace 6 incorporated in the vessel 2, a gas supply part 16 pressurizing the inside of the vessel 2, and the water cooling type cables 12a, 12b for conducting the induction coil 9 in the melting furnace 6 and high frequency power supply 10. A pair of metallic pipes 20a, 20b having a flange 24 overhanging on an outer peripheral side and a water passing passage 22 passing through along the longitudinal direction pass through an opening 5 in which the cables 12a, 12b pass through the vessel 2. A pair of insulation plates 30, 32 nipping the inside and outside of the flange 24 pass through the metallic pipes 20a, 20b. The insulation plates 30, 32 are fixed to a lid plate 44 which blocks the opening part 5 and through which the metallic pipes 20a, 20b pass. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pressure induction melting apparatus for producing, for example, high nitrogen steel.
[0002]
[Prior art]
[Patent Document 1]
In recent years, attempts have been made to improve corrosion resistance and hardness by adding nitrogen to stainless steel. In order to produce such a high-nitrogen-containing stainless steel, a melting casting apparatus disclosed in Japanese Patent Application Laid-Open No. 2000-202611 is known.
[0003]
In order to obtain the high nitrogen steel, for example, a pressure induction melting apparatus 60 as shown in FIG. 5A is also used. The melting apparatus 60 includes the pressure vessel 2, the induction melting furnace 6 disposed inside the pressure vessel 2, and the external high-frequency power supply 10. As shown in FIG. 5A, the pressure vessel 2 includes a hemispherical lid 3 made of a thick metal plate and a cylindrical main body 4, and the main body 4 has an opening 5 communicating with the outside. It has been established as possible.
As shown in FIG. 5A, the induction furnace 6 has an upward opening and an induction coil 9 provided spirally on the outside. Between both ends of the coil 9 and the high-frequency power supply 10, a pair of water-cooling cables 12a and 12b penetrating the opening 5 of the main body 4 are wired.
[0004]
FIG. 5B is an enlarged view of the vicinity of the opening 5 of the main body 4 in the pressure vessel 2. As shown in the figure, the water-cooled cables 12a and 12b are made up of a synthetic rubber insulating tube 13 covering the outer periphery, a conducting wire (cable) 14 penetrating the center, and a water supply unit 15 for circulating cooling water between the two. Multiplex structure. The cooling water is used to prevent the induction coil 9 and the conductive wire 14 from being overheated due to the current-carrying resistance and the surrounding magnetic field. As shown in FIG. 5B, a disc-shaped lid plate 62 is fixed to a flange 5 b at the tip of a cylindrical portion 5 a surrounding the opening 5 with bolts 65 and nuts 66. The cover plate 62 has a built-in hollow portion 63 for circulating cooling water, and has a pair of upper and lower through holes 64 formed therein.
[0005]
Outside the lid plate 62, a pair of insulating plates 68 and 70 are fixed by bolts 74 penetrating therethrough. In the insulating plates 68 and 70, a pair of through holes 69 and 71 that individually communicate with the pair of through holes 64 are formed.
As shown in FIG. 5B, the water cooling cables 12a and 12b individually pass through a pair of through holes 64, 69 and 71 which are coaxial with each other. The insulating tubes 13 located in the through holes 64, 69, 71 are fixed to the insulating ring 72, and the insulating ring 72 is supported between the insulating plates 68, 70. .
[0006]
As shown in FIG. 5A, a raw material for stainless steel (not shown) is charged into an induction melting furnace 6 in a closed pressure vessel 2, and a high-frequency current is applied to an induction coil 9. The raw material is induction-heated and melted by the magnetic field formed around it. The inside of the pressure vessel 2 is previously set to a nitrogen gas atmosphere of about 4 atm.
Next, the raw material melted in the induction melting furnace 6 is cast into a mold (not shown) arranged beforehand in the pressure vessel 2, and then solidifies to form the stainless steel ingot. Prior to such solidification, the nitrogen in the nitrogen gas atmosphere dissolves into the molten metal, so that the above-described ingot of high-nitrogen-containing stainless steel can be obtained.
[0007]
By the way, when the inside of the pressure vessel 2 is pressurized to the high pressure as described above, the insulating tube 13 of the water-cooled cables 12a, 12b is pressed, so that the water supply section 15 contracts. As a result, it becomes difficult for the cooling water to flow, and the reduced cooling water is heated by the heat from the induction melting furnace 6 to become steam. As a result, the induction coil 9 and the conductive wire 14 are overheated, and there is a problem that they may be damaged.
When the water supply section 15 contracts, as shown in FIG. 5 (B), the insulating ring 72 fixed to the water-cooled cables 12a, 12 breaks the fixed portion k. There is also a problem that the nitrogen gas atmosphere leaks rapidly to the outside.
[0008]
[Problems to be solved by the invention]
The present invention solves the problems in the conventional technology described above, and a water-cooled cable that connects an induction coil of an induction melting furnace built in a pressure vessel to an external high-frequency power source does not deform even when pressurized. It is another object of the present invention to provide a pressure induction melting apparatus capable of reliably circulating cooling water inside.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention has been conceived by forming a portion of a water-cooled cable that penetrates a pressure vessel with a metal pipe.
That is, a pressurized induction melting apparatus of the present invention (claim 1) comprises a sealable pressure vessel, an induction melting furnace built in the pressure vessel and provided with an induction coil around the pressure vessel, and a gas for pressurizing the inside of the pressure vessel. The supply unit includes a pair of water-cooled cables that conduct between the induction coil and the high-frequency power supply outside the pressure vessel, and the pair of water-cooled cables has an intermediate portion in an opening that penetrates the pressure vessel. A pair of metal pipes having a flange protruding on the outer peripheral side and a water passage penetrating along the longitudinal direction penetrates, and a pair of insulating plates sandwiching the inside and outside of the flange penetrate the metal pipe and a pair of insulating plates. The plate is fixed to a lid plate that closes the opening and penetrates the metal pipe.
[0010]
According to this, in the pair of water-cooled cables, at positions penetrating through the opening of the pressure vessel, metal pipes for circulating the cooling water in the inner hollow portion are individually arranged, and the metal pipes are connected via the flange. Supported by the lid plate while being sealed between a pair of insulating plates. As a result, even if the inside of the pressure vessel is pressurized, there is no problem in circulation of the cooling water, and no gap is formed between each metal pipe and each insulating plate, so that the pressure in the pressure vessel is maintained at a predetermined level. In addition, it can be reliably dissolved in a target metal or alloy. Therefore, it is possible to reliably and safely induce and melt a metal or alloy containing an alloy component which becomes a gas at normal temperature under a pressurized atmosphere.
A sealing material such as an O-ring is sandwiched between the flange of the metal pipe and the pair of insulating plates or between the outer insulating plate and the cover plate. The insulating plate is made of, for example, a synthetic resin such as a phenol resin (trade name: Bakelite) or an organic or inorganic insulating material such as mica.
[0011]
In addition, according to the present invention, a pressure induction melting device is provided in which at both ends of the metal pipe, a coupler having a conductor connection part for connecting to a conductor of the water-cooled cable and a water hole are arranged. Is also included. According to this, the cooling water that has passed through the hollow part in the metal pipe is sent to the water supply part located between the conductive wire (cable) and the insulating tube in the water-cooled cable via the water hole of the coupler, and the metal pipe The high-frequency current that has conducted itself is conducted to the conductor located at the center of the water-cooled cable via the conductor connection of the coupler. Therefore, the circulation of the cooling water and the conduction of the high-frequency current can be reliably achieved between the metal pipe and the water-cooled cables on both sides thereof.
[0012]
Further, according to the present invention, a gap is formed between the pair of metal pipes and the lid plate that penetrates the metal pipe, and an insulating tape is wound around the outer periphery of the metal pipe in the gap. A pressure induction melting device (claim 3) is also included.
According to this, since the insulation between the metal pipe and the cover plate is further secured, it is possible to reliably prevent a situation in which a current flowing through the metal pipe itself is inadvertently leaked.
[0013]
Further, the present invention also includes a pressure induction melting apparatus (claim 4) in which the pressure vessel is provided with a mold for casting the metal melted in the induction melting furnace into a predetermined shape. According to this, by casting the molten metal or alloy melted in the induction furnace in the pressure vessel into the mold, the molten metal is solidified while being pressurized by the gas atmosphere in the pressure vessel. As a result, an ingot containing an alloy component in an amount that cannot be obtained at atmospheric pressure can be reliably obtained. In addition, a press frame, a tundish, or the like according to a conventional method may be arranged in the opening of the mold.
[0014]
Further, according to the present invention, the gas supply unit for pressurizing the inside of the pressure vessel is connected to a vacuum device for pre-evacuating or depressurizing the inside of the pressure vessel. Is also included. According to this, after the inside of the pressure vessel is once evacuated or depressurized by the vacuum device, the gas of the desired component to be added to the metal or alloy is switched by switching the flow path of the gas supply unit to a predetermined pressure in the pressure vessel. It can be supplied under pressure. Therefore, it is possible to reliably obtain a molten metal or an ingot of a metal or an alloy containing a desired amount of an alloy component. In addition, as said vacuum apparatus, a vacuum pump is mentioned, for example.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. In the following, the same reference numerals are used for the same parts and elements as those in the conventional technique shown in FIG.
FIG. 1A schematically shows a pressure induction melting apparatus 1 of the present invention. The melting apparatus 1 includes a sealable pressure vessel 2, an induction melting furnace 6 built in the inside thereof, a gas supply unit 16 for pressurizing the inside of the pressure vessel 2, and a high-frequency power source 10 located outside the vessel 2. And.
As shown in FIG. 1A, the pressure vessel 2 includes a hemispherical lid 3 made of a stainless steel metal plate such as SUS304 and a cylindrical main body 4, and a lower part of the main body 4. An opening 5 communicating with the outside is provided. The lid 3 can be opened and closed, and one end of a pipe 17 of the gas supply unit 16 is connected.
[0016]
As shown in FIG. 1 (A), the induction furnace 6 includes an induction coil 9 which opens upward and is spirally provided outside the opening. Between both ends of the coil 9 and the high-frequency power supply 10, a pair of water-cooling cables 12a and 12b penetrating the opening 5 of the main body 4 are wired. Note that the pair of water-cooled cables 12a, 12b may each be in the form of a plurality of two or more cables.
Further, in the pressure vessel 2, a mold 50 that opens upward adjacent to the induction melting furnace 6, a press frame 56 made of a refractory above the mold 50, and a tundish 54 are arranged. In addition, as shown in FIG. 1 (A), the gas supply unit 16 includes a gas storage unit 19 and a vacuum pump (vacuum device) 18, which are connected to the ends, and have a pressure via a three-way switching valve 17a. It has a three-pronged pipe 17 connected to the lid 3 of the container 2.
[0017]
FIG. 1B is an enlarged view of the vicinity of the opening 5 of the main body 4 in the pressure vessel 2.
As shown in FIG. 1 (B), a pair of water-cooling cables 12a, 12b are wired inside and outside the pressure vessel 2, respectively, and these are individually connected by metal pipes 20a, 20b. Each of the water-cooled cables 12a and 12b is a multiplex structure including a synthetic rubber insulating tube 13 covering the outer periphery, a conducting wire (cable) 14 penetrating the center, and a water supply unit 15 for circulating cooling water between the two. is there. Such cooling water is used to prevent the induction coil 9 and the conductive wire 14 from being overheated by the internal conduction resistance and the surrounding magnetic field.
[0018]
The metal pipes 20a and 20b are made of, for example, oxygen-free copper. As shown in FIGS. 1 (B) and 2 (A), the metal pipes 20a and 20b extend along the entire length in the longitudinal direction as a cooling water passage. And a disk-shaped flange 24 projecting to the outer peripheral side in the middle of the pipe main body 21. The flange 24 is fixed, for example, by welding to a predetermined position of the pipe body 21.
As shown in FIG. 1 (B), couplers 25 and 26 made of the same oxygen-free copper as described above are welded to both ends of the pipe main body 21 of the metal pipes 20a and 20b. The couplers 25 and 26 are provided with a water hole 28 communicating between the hollow portion 22 of the metal pipes 20a and 20b and the water supply portion 15 of the water cooling cables 12a and 12b, and an end of the conducting wire 14 of the water cooling cables 12a and 12b. A conductor connecting portion 29 for connection is built in.
[0019]
Further, as shown in FIG. 1B, the flanges 24 of the metal pipes 20a, 20b are sandwiched between a pair of insulating plates 30, 32 from both inside and outside. The insulating plates 30 and 32 are made of, for example, a urea resin (trade name: Bakelite). As shown in FIG. 2B, a disc-shaped main body 31 and surfaces 30a and 32a where the main bodies 31 face each other are provided. A pair of upper and lower recesses 34 for receiving half of the thickness of the flanges 24 and 24 and a through hole 36 penetrating from the center of the recess 34 to the outer surfaces 30b and 32b are provided symmetrically. A plurality of bolt holes 38 are drilled around each body 31.
As shown in FIG. 1B, in the metal pipes 20a and 20b, the respective pipe main bodies 21 are inserted into the through holes 36 of the insulating plates 30 and 32, and the respective flanges 24 are formed in the recesses 34 and 34 of the insulating plates 30 and 32. Are sandwiched via an O-ring (sealant) 40.
[0020]
As shown in FIG. 1B, the pair of insulating plates 30 and 32 supporting the metal pipes 20a and 20b with the respective flanges 24 interposed therebetween are formed by bolts 42 passing through the bolt holes 38 and 38 of the cover plate 44. By screwing into the female screw hole 45, the pressure vessel 2 is fixed to the cover plate 44 that closes the opening 5.
As shown in FIG. 1B, the opening 5 is closed by a plurality of sets of bolts 46 and nuts 47 on a ring-shaped flange 5b welded to the tip of a cylindrical portion 5a surrounding the opening 5 of the pressure vessel 2. The metal cover plate 44 is fixed.
[0021]
The cover plate 44 has a pair of upper and lower through holes 48 that penetrate the pipe bodies 21 of the metal pipes 20a and 20b through a gap, and a female threadedly connected to a bolt 42 that penetrates the pair of insulating plates 30 and 32. And a screw hole 45.
The cover plate 44 has a disk shape made of the same stainless steel as described above, and has a hollow portion 49 in which cooling water is circulated independently. Further, the cover plate 44 sandwiches the inner and outer double O-rings 40, 40 having different diameters between the flange plate 5b and the adjacent insulating plate 32, respectively. An insulating tape T is wound around each of the pipe bodies 21 of the metal pipes 20a and 20b that penetrate through the through hole 48 of the cover plate 44 through a gap, and a gap between the metal cover plate 44 and each of the pipe bodies 21 is formed. Insulated.
[0022]
The above-described pressure induction melting apparatus 1 is operated as follows.
After the lid 3 is opened and the raw material corresponding to the target alloy component is charged into the induction melting furnace 6, the lid 3 is closed and the pressure vessel 2 is sealed as shown in FIG. In this state, after the vacuum pump 18 is driven to evacuate the pressure vessel 2 once through the pipe 17, for example, nitrogen gas is supplied from the gas storage unit 19 of the gas supply unit 16 into the pressure vessel 2 via the pipe 17. The pressure is increased to about several to several tens of atmosphere by forcibly blowing.
[0023]
Next, a high-frequency current of several kHz is transmitted from the high-frequency power supply 10 to the induction coil 9 of the induction melting furnace 6 via the inner and outer water-cooled cables 12a and 12b and the metal pipes 20a and 20b. A magnetic field penetrating the induction melting furnace 6 from the induction coil 9 is formed by the high-frequency current, and the raw material charged into the induction melting furnace 6 is heated by the eddy current by the magnetic field and gradually melts into molten metal. At the same time, the molten metal is stirred by the magnetic field.
Next, the induction melting furnace 6 is tilted toward the tundish 54 in the pressure vessel 2 shown in FIG. 1A by tilting means (not shown). Pour the water inside. As a result, for example, an ingot made of stainless steel containing a large amount of nitrogen can be obtained.
[0024]
Through the above-described steps of energization, melting, and casting, the inside of the force-transmitting vessel 2 is pressurized to a pressure of several atmospheres or more, but the portions of the water-cooled cables 12a and 12b that penetrate through the opening 5 of the pressure vessel 2 include metal. Since the pipes 20a and 20b are arranged, the cooling water can be reliably circulated through the water supply sections 15 of the water cooling cables 12a and 12b inside and outside the pressure vessel 2. As a result, it is possible to reliably prevent the conductor 14 of the water cooling cables 12a and 12b in the pressure vessel 2 and the induction coil 9 from being overheated as in the related art. In addition, since the metal pipes 20a and 20b have the flange 24 sandwiched between the insulating plates 30 and 32 via the O-ring 40 as a sealing material, there is no gap caused by shrinkage deformation as in the related art, and the pressure vessel The pressurized state in 2 can be reliably maintained. Therefore, according to the pressurized induction melting apparatus 1 described above, it is possible to safely and reliably perform the induction melting of the metal and the ingot casting under the pressurized atmosphere.
[0025]
【Example】
Here, specific examples of the present invention will be described together with comparative examples.
Two pressure vessels 2 each formed by a main body 2 made of a thick plate of stainless steel (SUS304) having a plate thickness of 20 mm and a lid 3 and having an internal volume of 4.0 m ³ were prepared. Such a pressure vessel 2 can withstand an internal pressure of about 1 MPa.
One pressure vessel 2 includes the induction melting furnace 6, the gas supply unit 16, the mold 50, the water-cooled cables 12a and 12b, the high-frequency power source 10, and the opening of the pressure vessel 2 as shown in FIG. 5, the pressure induction melting apparatus 1 of the embodiment in which metal pipes 20a and 20b and insulating plates 30 and 32 were arranged inside and outside.
[0026]
The other pressure vessel 2 includes the induction melting furnace 6, the gas supply unit 16, the mold 50, the water-cooled cables 12a and 12b, the high-frequency power source 10, and the opening of the pressure vessel 2 as shown in FIG. 5, a pressure induction melting apparatus of a comparative example in which insulating plates 68 and 70 through which the water-cooled cables 12a and 12b penetrate was disposed inside and outside.
In each example, the induction melting furnace 6, the mold 50, and the water-cooled cables 12a, 12b are common, and the cross-sectional area of the hollow portion 22 of the metal pipes 20a, 20b in the embodiment is determined by cutting off the water supply section 15 of the water-cooled cables 12a, 12b. It was the same as the area.
[0027]
After loading 50 kg of raw material for stainless steel (SUS304) into the induction melting furnace 6 of each example, closing the lid 3 and sealing the pressure vessel 2, the inside of the pressure vessel 2 of each example is closed by the gas supply unit 16. Once a vacuum was established, nitrogen gas was gradually filled and pressurized.
In addition, a high-frequency current of 2 kHz is supplied to the induction coil 9 of the induction melting furnace 6 from the high-frequency power supply (70 kW) 10 of each example via the water-cooled cables 12a and 12b or the metal pipes 20a and 20b on the way, thereby supplying the above-mentioned raw material. Was heated and dissolved. At this time, the temperature at the time of dissolution was 1600 ° C. and kept for 70 minutes.
Then, in each example, the flow rate and temperature of the cooling water in the water-cooled cables 12a and 12b were measured with respect to changes in the pressure (internal pressure) in the pressure vessel 2. The results are shown in the graph of FIG.
[0028]
As shown in the graph of FIG. 3, in the pressurized induction melting apparatus 1 of the embodiment, even if the internal pressure of the pressure vessel 2 increases from 0.1 MPa to 0.9 MPa, the flow rate of the cooling water slightly decreases and the cooling is performed. The temperature of the water rose only about 10 ° C.
On the other hand, in the pressurized induction melting apparatus of the comparative example, as shown in the graph of FIG. 3, as the internal pressure of the pressure vessel 2 increases from 0.1 MPa to 0.8 MPa, the flow rate of the cooling water is about 21 liters. / Min and the temperature of the cooling water increased by about 38 ° C. In this comparative example, the flow rate and the temperature at an internal pressure of 0.9 MPa could not be measured because the temperature of the cooling water was too high to be dangerous.
The above results show that, in the embodiment, the metal pipes 20a and 20b are disposed near the opening 5 of the pressure vessel 2, so that even if the pressure vessel 2 is pressurized, the flow rate of the cooling water hardly decreases. This indicates that the rise in the temperature of the cooling water is also suppressed. These results confirmed the effect of the pressure induction melting apparatus 1 of the present invention.
[0029]
FIG. 4 shows a modification of the vicinity of the metal pipes 20a and 20b in the pressure induction melting apparatus 1. In FIG. 4, the flanges 24 of the metal pipes 20a and 20b are sandwiched between a pair of insulating plates 33a and 33b from both inside and outside.
The insulating plates 33a and 33b are also made of the same resin as described above. As shown in FIG. 4, the inner insulating plate 33a has a pair of upper and lower through-holes 36 having a flat disk shape on both sides. The outer insulating plate 33b has, on its inner surface, a pair of upper and lower deep recesses 34 for receiving the entire thickness of the flanges 24, 24, and through holes 36, 36 penetrating from the center of these recesses 34 to the outer surface. have.
[0030]
Further, a plurality of bolt holes 38 are formed around the insulating plates 33a and 33b. As shown in FIG. 4, the metal pipes 20a and 20b allow the respective pipe bodies 21 to pass through the respective through holes 36 of the insulating plates 33a and 33b, and the flanges 24 thereof are inserted into the concave portions 34 and 34 of the insulating plate 33b. It is inserted and sandwiched via an O-ring (sealant) 40. An O-ring 40 is also interposed between each flange 24 and the insulating plate 33a.
[0031]
As shown in FIG. 4, the pair of insulating plates 33 a and 33 b are fixed to a cover plate 44 that closes the opening 5 of the pressure vessel 2 by bolts 42 penetrating the bolt holes 38 and 38. Reference numeral 44 denotes a plurality of sets of bolts 46 and nuts 47 fixed to a ring-shaped flange 5b provided at the end of a cylindrical portion 5a surrounding the opening 5 of the pressure vessel 2. An insulating tape T is wound around each of the pipe bodies 21 of the metal pipes 20a and 20b that penetrate through the through hole 48 of the cover plate 44 through a gap, and the gap between the metal cover plate 44 and the pipe body 21 is formed. Insulated.
Even in the embodiment using the insulating plates 33a and 33b, the same airtightness as the insulating plates 30 and 32, water permeability of the cooling water in the metal pipes 20a and 20b, and the like can be ensured.
[0032]
The present invention is not limited to the embodiments described above.
For example, as long as the lid 3 can be opened and closed, the pressure vessel 2 may have a configuration in which the cylindrical main body 4 is arranged horizontally long.
Further, the metal pipes 20a and 20b are not limited to the oxygen-free copper and may be made of various copper alloys or aluminum alloys. For example, when the pipe body 21 is made of an extruded aluminum alloy, a plurality of hollow portions (22) can be integrally formed at substantially the same radial position as the water passage portion 15 of the water-cooled cables 12a and 12b. A disk-shaped flange 24 may be welded to the middle outer peripheral side of the pipe body 21 for assembly.
[0033]
Further, the pipe body 21 is not limited to a circular cross section, and may be a form having a cross section of a regular polygon or a deformed polygon having a quadrangle or more. The flange 24 is not limited to a disk shape and may have a regular shape having a quadrangle or more. The shape may be a polygon or a deformed polygon.
Further, the pair of insulating plates sandwiching the flange 24 may be made of a plate material having flat both side surfaces like the insulating plate 33a.
The gas to be pressurized in the pressure vessel 2 is not limited to the above-mentioned nitrogen, but can be appropriately selected according to the target metal or alloy component.
[0034]
【The invention's effect】
According to the above-described pressurized induction melting apparatus of the present invention (claim 1), a metal pipe for circulating cooling water through an inner hollow portion is individually provided at a position penetrating an opening of a pressure vessel in a water-cooled cable. And the metal pipe is supported by the lid plate while being sandwiched between a pair of insulating plates via a flange. As a result, even if the inside of the pressure vessel is pressurized, there is no problem in circulation of the cooling water, and no gap is formed between each metal pipe and each insulating plate, so that the pressure in the pressure vessel is maintained at a predetermined level. Thus, it can be reliably dissolved in a target metal or alloy. Therefore, it is possible to reliably and safely induce and melt an alloy containing an alloy component which becomes a gas at normal temperature under a pressurized atmosphere.
[0035]
According to the pressurized induction melting apparatus of the second aspect, the circulation of the cooling water and the conduction of the high-frequency current can be reliably achieved between the metal pipe and the water cooling cables on both sides thereof.
Furthermore, according to the pressure induction melting apparatus of the third aspect, the insulation between the metal pipe and the cover plate is further secured, so that the current flowing through the metal pipe itself is prevented from inadvertently leaking. it can.
[0036]
According to the pressure induction melting apparatus of claim 4, when the molten metal of the metal melted in the induction furnace in the pressure vessel is cast into the mold, the molten metal is pressurized by the gas atmosphere in the pressure vessel. Because of solidification, an ingot containing an alloy component in an amount that cannot be obtained under atmospheric pressure can be reliably obtained.
Further, according to the pressurized induction melting apparatus of claim 5, after the inside of the pressure vessel is once evacuated or depressurized by the vacuum device, the desired gas to be added to the metal is switched by switching the flow path of the gas supply unit. It can be supplied in a predetermined pressurized state in the pressure vessel.
[Brief description of the drawings]
FIG. 1A is a schematic view showing a pressure induction melting apparatus of the present invention, and FIG. 1B is an enlarged view of a dashed line portion B in FIG.
FIGS. 2A and 2B are perspective views of a metal pipe or an insulating plate shown in FIG. 1B.
FIG. 3 is a graph showing the relationship between the internal pressure of a pressure vessel, the flow rate of cooling water, and the temperature in each of the pressurized induction melting apparatuses of Examples and Comparative Examples.
FIG. 4 is a partial cross-sectional view showing a modification of the portion shown in FIG.
FIG. 5A is a schematic view showing a conventional pressure induction melting apparatus, and FIG. 5B is an enlarged view of a dashed line portion B in FIG.
[Explanation of symbols]
1 ……………………………………………………………………………………………………………………… Pressure vessel 5 ……………………………… Opening 6 Induction melting furnace 9 Induction coil 10 High frequency power supplies 12a, 12b … Water-cooled cable 14… Conductor 16… Gas supply unit 18… Vacuum pump (vacuum device)
20a, 20b Metal pipe 22 Hollow part (water passage)
24 Flange 25, 26 Coupler 28 Coupler hole 29 Water passage hole 29 …………………………………………………… ... Conducting wire connecting portions 30, 32, 33a, 33b Insulating plate 44... Lid plate 50... …………… Insulation tape

Claims (5)

A sealable pressure vessel;
An induction melting furnace built in the pressure vessel and provided with an induction coil around;
A gas supply unit for pressurizing the inside of the pressure vessel,
A pair of water-cooled cables that conduct between the induction coil and the high-frequency power supply outside the pressure vessel,
In the opening through which the pair of water-cooled cables penetrates the pressure vessel, a pair of metal pipes having a flange projecting to an intermediate outer peripheral side and a water passage penetrating along the longitudinal direction penetrates, and the inside and outside of the flange are pierced. A pair of insulating plates sandwiching the metal pipe penetrates the metal pipe, and the pair of insulating plates is fixed to a lid plate that closes the opening and penetrates the metal pipe.
A pressure induction melting apparatus characterized by the above-mentioned. At both ends of the metal pipe, a coupler incorporating a conductor connection portion and a water hole connected to the conductor of the water-cooled cable are arranged.
The pressurized induction melting apparatus according to claim 1, wherein: A gap is formed between the pair of metal pipes and the lid plate that penetrates the insulating pipe, and an insulating tape is wound around the outer circumference of the metal pipe in the gap.
The pressure induction melting apparatus according to claim 1 or 2, wherein: In the pressure vessel, a mold for casting the metal melted in the induction melting furnace into a predetermined shape is arranged,
The pressure induction melting apparatus according to any one of claims 1 to 3, wherein: The gas supply unit for pressurizing the inside of the pressure vessel, the inside of the pressure vessel is previously evacuated, or is also connected to a vacuum device for reducing the pressure,
The pressurized induction melting apparatus according to any one of claims 1 to 4, wherein:

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