Method and apparatus for producing oxygen-free copper or oxygen-free copper alloy

Abstract

The present invention relates to a method and an apparatus for producing oxygen-free copper or an oxygen-free copper alloy. Specifically, the present invention can suppress the generation of holes, cracks, etc. in an ingot through a sufficient and uniform deoxidation reaction, and can produce high-quality oxygen-free copper or an oxygen-free copper alloy with good surface quality during rolling. At the same time, it can produce oxygen-free copper or an oxygen-free copper alloy at low cost through fuel cost savings, and relates to a method and an apparatus for producing oxygen-free copper or an oxygen-free copper alloy that can reduce the damage of the lining material of a melting furnace and the fire risk.

Description

Technical Field

[0001] The present invention relates to a method and apparatus for manufacturing oxygen-free copper or an oxygen-free copper alloy. Specifically, the present invention can suppress the generation of holes, cracks, etc. in an ingot through a sufficient and uniform deoxidation reaction, and can manufacture high-quality oxygen-free copper or an oxygen-free copper alloy with good surface quality during rolling. At the same time, the oxygen-free copper or the oxygen-free copper alloy can be manufactured at low cost through fuel cost reduction, and the present invention relates to a method and apparatus for manufacturing an oxygen-free copper or an oxygen-free copper alloy that can reduce the damage of the lining material of a melting furnace and the fire risk.

Background Art

[0002] When there is oxygen in copper (Cu), hydrogen embrittlement occurs due to the reaction of Cu 2 O with hydrogen to generate H 2 O, and the corrosion resistance also decreases. Therefore, copper (Cu) removed of oxygen with a deoxidizer to reduce the oxygen content to about 10 ppm or less is called oxygen-free copper (OFC).

[0003] In recent years, oxygen-free copper (OFC) wire has been used to improve performance and reliability in windings of electric vehicle motors, wires for solar cell modules, windings for transformers, submarine cables, etc. In particular, with the growth of the electric vehicle and solar power markets, an increase in the demand for oxygen-free copper (OFC) is expected, and due to the miniaturization of electronic devices, the thinning of oxygen-free copper (OFC) wire is required, and thus, improvements in the softness and workability of oxygen-free copper (OFC) have attracted attention.

[0004] As methods for manufacturing oxygen-free copper (OFC) wire, there are a dip forming method in which oxygen-free copper is solidified on the outer periphery of a core rod and continuously rolled, an up-cast method in which an oxygen-free copper mold is vertically arranged and an ingot solidified through cooling in the mold is continuously pulled up, a horizontal continuous casting method in which a mold is horizontally installed on the side wall of a casting furnace and an ingot solidified through cooling of oxygen-free copper in the mold is continuously drawn out, and the like.

[0005] However, in such a conventional method for producing oxygen-free copper, since the production rate is as low as 10 ton / hr or less, when producing tough pitch copper wire rod materials containing 100 ppm or more of oxygen, the belt & wheel type continuous casting and rolling method, so-called SCR (Southwire Continuous Rod) method with a production rate of 30 ton / hr or more is used.

[0006] The belt & wheel type continuous casting and rolling method manufactures an ingot by injecting molten copper flowing out from a vertical continuous melting furnace (shaft furnace) into a rotating mold formed between a wheel and a belt, solidifying it through cooling, continuously pulling it out, and manufacturing it into a wire rod while continuously rolling it as it is.

[0007] In particular, Japanese Registered Patent Publication No. 4593397 discloses a continuous casting and rolling method using a rotating moving mold that performs deoxidation treatment with a reducing gas and adjusts the hydrogen concentration with an inert gas from melting to casting in a melting furnace. Japanese Registered Patent Publication No. 3552043 discloses a belt & wheel type continuous casting and rolling method in which a solid reducing agent is arranged in a cylinder for transferring molten copper flowing out from a melting furnace and a tundish for injecting this into a rotating moving mold.

[0008] However, in the case of a method of performing deoxidation using a reducing gas, in order to increase the concentration of carbon monoxide (CO) as a reducing gas in the melting furnace, incomplete combustion must be induced. However, due to such incomplete combustion, there is a problem that the fuel cost increases and the manufacturing cost of the produced oxygen-free copper wire rod increases. At the same time, the inventors have confirmed through literature that when performing a deoxidation reaction with a reducing gas in the melting furnace for a long period of time, carbon monoxide (CO) as a reducing gas can damage the interior material of the inner wall of the melting furnace, and have confirmed that the wear of the interior material progresses rapidly when actually working for a long period of time.

[0009] In addition, when a solid reducing agent is placed in a cylinder for transferring molten copper discharged from a melting furnace and a tundish for injecting the molten copper into a rotary moving mold, since the contact time between the molten copper and the solid deoxidizing agent is short, it is difficult to ensure deoxidation performance, and a large oxygen deviation appears. In addition, since there is a high possibility that foreign substances such as solid deoxidizing agents will flow into the produced oxygen-free copper wire rod, as a result, there is a high possibility that holes, cracks, etc. will occur in the ingot, and the surface quality of the wire rod may deteriorate during rolling.

[0010] Therefore, it is possible to suppress the generation of holes, cracks, etc. in the ingot through a sufficient and uniform deoxidation reaction, and it is possible to produce high-quality oxygen-free copper or oxygen-free copper alloy with good surface quality during rolling. At the same time, it is possible to produce oxygen-free copper or oxygen-free copper alloy at low cost through fuel cost savings, and there is an urgent need for a manufacturing method and apparatus for oxygen-free copper or oxygen-free copper alloy that can reduce the damage of the lining material of the melting furnace and the fire risk.

Summary of the Invention

Problems to be Solved by the Invention

[0011] An object of the present invention is to provide a method and apparatus for producing oxygen-free copper or oxygen-free copper alloy that can suppress the generation of holes, cracks, etc. in the ingot through a sufficient and uniform deoxidation reaction, and can produce high-quality oxygen-free copper or oxygen-free copper alloy with good surface quality during rolling.

[0012] Another object of the present invention is to provide a method and apparatus for producing oxygen-free copper or oxygen-free copper alloy that can produce oxygen-free copper or oxygen-free copper alloy at low cost through fuel cost savings, and can reduce the damage of the lining material of the melting furnace and the fire risk.

Means for Solving the Problems

[0013] To solve the above problems, the present invention A method for manufacturing oxygen-free copper or an oxygen-free copper alloy, comprising the steps of: charging a copper or copper alloy material and a solid deoxidizer into a melting furnace, melting and deoxidizing the copper or copper alloy material; transferring the deoxidized copper or copper alloy molten metal through a transfer pipe; discharging the copper or copper alloy molten metal transferred through a pour pot into a casting machine; and producing an ingot from the copper or copper alloy molten metal in the casting machine.

[0014] Here, the solid deoxidizer includes one or more selected from the group consisting of graphite, charcoal, activated carbon, and coke, and a method for manufacturing oxygen-free copper or an oxygen-free copper alloy is provided.

[0015] Also, the charging amount of the solid deoxidizer is 1 kg / ton or more and 6 kg / ton or less based on the charging amount of the copper or copper alloy material, and a method for manufacturing oxygen-free copper or an oxygen-free copper alloy is provided.

[0016] And, the size of the solid deoxidizer is 0.5 mm or more and 30 mm or less, and a method for manufacturing oxygen-free copper or an oxygen-free copper alloy is provided.

[0017] Furthermore, a dust collector is further provided at the upper part of the melting furnace, and a method for manufacturing oxygen-free copper or an oxygen-free copper alloy is provided.

[0018] On the other hand, the concentration of carbon monoxide (CO) inside the melting furnace is adjusted to 3.5% by volume or less, and a method for manufacturing oxygen-free copper or an oxygen-free copper alloy is provided.

[0019] Also, the residence time of the solid deoxidizer inside the melting furnace is 5 minutes to 2 hours, and a method for manufacturing oxygen-free copper or an oxygen-free copper alloy is provided.

[0020] And, at the discharge port of the pu-pot, there is provided a spout torch for applying a flame to seal (sealing) the molten copper or copper alloy discharged to the casting machine from the outside, and a spout burner for applying a flame to remelt and remove the molten copper or copper alloy fixed to the outer surface of the discharge part, and there is provided a method for producing oxygen-free copper or oxygen-free copper alloy, characterized in that.

[0021] Here, the transfer pipe includes an upper slag vessel for removing impurities generated during melting of the copper or copper alloy material or slag of the solid deoxidizer, and a holding furnace functioning as a buffer for compensating for the difference between the production rate and the melting rate of the ingot while maintaining the temperature of the molten copper or copper alloy, and a lower slag vessel for removing impurities floating on the molten copper or copper alloy, and there is provided a method for producing oxygen-free copper or oxygen-free copper alloy, characterized in that.

[0022] Here, the upper slag vessel is characterized in that the width of the shape of the discharge port connected to the holding furnace is longer than the height, or a partition wall is provided above the discharge port, and there is provided a method for producing oxygen-free copper or oxygen-free copper alloy.

[0023] Further, there is provided a method for producing oxygen-free copper or oxygen-free copper alloy, characterized in that the concentration of carbon monoxide is adjusted to more than 2.5% by volume and not more than 4.0% by volume at one or more positions selected from the group consisting of the holding furnace, the lower slag vessel, and the pu-pot.

[0024] And, the lower slag vessel is provided with a bubbler for injecting an inert gas into the molten copper or copper alloy, and there is provided a method for producing oxygen-free copper or oxygen-free copper alloy, characterized in that.

[0025] Here, the inert gas includes argon gas or nitrogen gas, and there is provided a method for producing oxygen-free copper or oxygen-free copper alloy, characterized in that.

[0026] Furthermore, the casting machine includes a moving mold casting machine including a rotating casting wheel and a belt provided at a certain distance from the surface of the casting wheel, and further includes a step of continuously rolling the ingot produced by the casting machine through a rolling mill. A method for producing oxygen-free copper or an oxygen-free copper alloy is provided, which is characterized in that.

[0027] On the other hand, an oxygen-free copper or an oxygen-free copper alloy produced by the method for producing an oxygen-free copper or an oxygen-free copper alloy is provided.

[0028] Here, an oxygen-free copper or an oxygen-free copper alloy is provided, which is characterized in that the alloy is in the form of a rod, a slab, or an ingot.

[0029] On the other hand, as a manufacturing apparatus for oxygen-free copper or an oxygen-free copper alloy, a melting furnace for melting a copper or copper alloy material; a transfer pipe for transferring the molten copper or copper alloy melted in the melting furnace; a pouring pot for discharging the molten copper or copper alloy transferred through the transfer pipe; and a casting machine for producing an ingot while cooling the molten copper or copper alloy discharged from the pouring pot; are included. In the melting furnace, a solid deoxidizer is charged together with the copper or copper alloy material. A manufacturing apparatus for oxygen-free copper or an oxygen-free copper alloy is provided.

[0030] Here, a manufacturing apparatus for oxygen-free copper or an oxygen-free copper alloy is provided, which is characterized in that the solid deoxidizer includes one or more selected from the group consisting of graphite, charcoal, activated carbon, and coke.

[0031] Also, a manufacturing apparatus for oxygen-free copper or an oxygen-free copper alloy is provided, which is characterized in that the charging amount of the solid deoxidizer is 1 kg / ton or more and 6 kg / ton or less based on the charging amount of the copper or copper alloy material.

[0032] Furthermore, a manufacturing apparatus for oxygen-free copper or an oxygen-free copper alloy is provided, which is characterized in that the size of the solid deoxidizer is 1 mm or more and 30 mm or less.

[0033] Provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy, characterized in that a dust collector is further provided above the melting furnace.

[0034] Also provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy, characterized in that the concentration of carbon monoxide (CO) inside the melting furnace is adjusted to 3.5% by volume or less.

[0035] Also provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy, characterized in that the residence time of the solid deoxidizer inside the melting furnace is 5 minutes to 2 hours.

[0036] On the other hand, at the discharge port of the pour pot, a spout torch that applies a flame to seal the molten copper or copper alloy discharged to the casting machine from the outside, and a spout burner that applies a flame to remelt and remove the molten copper or copper alloy adhering to the outer surface of the discharge part are provided. Provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy.

[0037] The transfer pipe also includes an upper slag vessel that removes impurities generated during the melting of the copper or copper alloy material or slag of the solid deoxidizer, a holding furnace that functions as a buffer to compensate for the difference between the production rate and the melting rate of the ingot while maintaining the temperature of the molten copper or copper alloy, and a lower slag vessel that removes impurities floating on the molten copper or copper alloy. Provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy.

[0038] Here, the upper slag vessel is characterized in that the width of the discharge port shape connected to the holding furnace is longer than the height, or a partition wall is provided above the discharge port. Provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy.

[0039] Also provided is a production apparatus for oxygen-free copper or an oxygen-free copper alloy, characterized in that the concentration of carbon monoxide is adjusted to more than 2.5% by volume and 4.0% by volume or less at one or more positions selected from the group consisting of the holding furnace, the lower slag vessel, and the pour pot.

[0040] And a bubbler for injecting an inert gas into the molten copper or copper alloy is provided in the lower slag vessel, and a manufacturing apparatus for oxygen-free copper or oxygen-free copper alloy is provided.

[0041] Furthermore, an inert gas contains argon gas or nitrogen gas, and a manufacturing apparatus for oxygen-free copper or oxygen-free copper alloy is provided.

[0042] On the other hand, the casting machine includes a moving mold casting machine including a rotating casting wheel and a belt provided at a certain interval from the surface of the casting wheel, and further includes a rolling mill for continuously rolling the ingot produced by the casting machine, and a manufacturing apparatus for oxygen-free copper or oxygen-free copper alloy is provided.

Effect of the Invention

[0043] The method and apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to the present invention apply a solid deoxidizer in a melting furnace instead of a cylinder or a tundish, and can suppress the generation of holes, cracks, etc. in the ingot through a sufficient and uniform deoxidation reaction, and can manufacture high-quality oxygen-free copper or oxygen-free copper alloy with good surface quality during rolling, showing an excellent effect.

[0044] In addition, the method and apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to the present invention have less deoxidation reaction by reducing gas in the melting furnace, so it is possible to prevent an increase in fuel cost and manufacturing cost due to incomplete combustion for generating reducing gas, and at the same time, it shows an excellent effect of suppressing damage to the interior materials of the melting furnace by reducing gas.

Brief Description of the Drawings

[0045]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0046] Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced here are provided in order to thoroughly and completely disclose the disclosed content and to fully convey the idea of the present invention to those skilled in the art. The same reference numerals throughout the specification indicate the same components.

[0047] FIG. 1 is a diagram schematically showing the configuration of an apparatus for manufacturing oxygen-free copper or an oxygen-free copper alloy according to the present invention.

[0048] The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to the present invention using the apparatus shown in FIG. 1 includes the steps of charging a copper or copper alloy material and a solid deoxidizer into a melting furnace 100, melting and deoxidizing the copper or copper alloy material, transferring the deoxidized copper or copper alloy molten metal through a transfer pipe 200, discharging the copper or copper alloy molten metal transferred through a poor pot 300 to a casting machine 400, and manufacturing an ingot from the copper or copper alloy molten metal with the casting machine 400. Further, it can include the step of continuously rolling the ingot through a rolling mill 500.

[0049] FIG. 2 is a diagram showing the melting furnace 100 in FIG. 1 in an enlarged manner.

[0050] Specifically, in the step of melting and deoxidizing the copper or copper alloy material, the copper or copper alloy material, preferably an electrolytic copper plate and a solid deoxidizer, is introduced through the inlet 120 at the upper part of the shaft furnace 110 shown in FIG. 2, and the electrolytic copper plate and the solid deoxidizer are alternately laminated and then melted and deoxidized by using the combustion heat of the combustion gas to maintain the temperature at about 1090°C to 1150°C through the burner 130 provided as one or more layers at the lower part.

[0051] In addition, at the upper part of the melting furnace 110, a dust collector 140 for sucking in dust generated by melting inside the melting furnace 110 and a scattering prevention device for preventing the scattering of relatively small solid deoxidizers among the solid deoxidizers may be further provided.

[0052] Conventionally, when a solid deoxidizer is introduced into a vertical continuous melting furnace, the solid deoxidizer floats on the upper part of the copper melt due to the difference in specific gravity. Also, on the upper part of the copper melt, copper or copper alloy materials that are not melted or only partially melted are introduced and laminated. Therefore, a sufficient deoxidation reaction due to sufficient contact between the copper melt and the solid deoxidizer hardly occurs. The solid deoxidizer has been applied to the transfer pipe through which the copper or copper alloy melt discharged from the melting furnace is transferred or the pouring pot discharged to the casting machine. However, the inventors of the present invention have completed the present invention by experimentally confirming that, rather, when the solid deoxidizer is applied to the melting furnace, a sufficient and uniform deoxidation reaction can be induced.

[0053] The solid deoxidizer may be introduced into the melting furnace 100 together with the copper or copper alloy material or alternately and repeatedly introduced. Also, the input amount of the solid deoxidizer can be adjusted to be 1 kg / ton or more and 6 kg / ton or less based on the input amount of the copper or copper alloy material. Also, the introduced solid deoxidizer stays in the melting furnace 100 for about 5 minutes to 2 hours.

[0054] Here, when the input amount of the solid deoxidizer is less than 1 kg / ton, the deoxidation reaction by the solid deoxidizer becomes insufficient, and the oxygen content in the produced ingot becomes excessive. As a result, holes, cracks, etc. may be induced, and the surface quality may deteriorate during rolling.

[0055] On the other hand, when the input amount of the solid deoxidizer exceeds 6 kg / ton, not only can an excessive amount of the solid deoxidizer that does not disappear in the melting furnace 100 and is transferred together with the copper melt in the transfer pipe 200 induce a backflow (overflow) of the copper melt in the transfer pipe 200, but also excessive smoke is generated when the excessive amount of the solid deoxidizer disappears by combustion in the melting furnace 100, and the burned fine sparks may be inhaled into a dust collector that may be further provided above the melting furnace 100 to induce a fire.

[0056] The solid deoxidizer can have a size of 30 mm or less, for example, 0.5 mm to 30 mm, preferably 1 mm to 30 mm. Preferably, the solid deoxidizer can be selected from one or more of the group consisting of graphite or graphite, charcoal, activated carbon, and coke, and more preferably can contain graphite or graphite. For reference, the size of the solid deoxidizer means the diameter of a sphere converted to have the same volume.

[0057] Here, when the size of the solid deoxidizer is less than 1 mm, due to the gas pressure rising upward in the melting furnace 100, the solid deoxidizer may be sucked into a dust collector provided above the melting furnace 100, inducing a fire or a failure of the dust collector. On the other hand, when the size of the solid deoxidizer exceeds 30 mm, it is not burned in the melting furnace 100 and partially blocks the transfer passage while being transferred together with the copper melt, so it may induce a backflow of the copper melt.

[0058] The melting furnace 100 generates combustion gas during fuel combustion through burners provided as one or more layers at the lower part. By adjusting the concentration of carbon monoxide (CO) generated by incomplete combustion to 1.5% by volume or less based on the total volume of the combustion gas, damage to the interior material of the inner wall of the melting furnace 100 caused by the carbon monoxide (CO) can be prevented or minimized.

[0059] On the other hand, in the step of transferring the deoxidized molten copper or copper alloy through the transfer pipe 200, the temperature is maintained at 1100°C to 1200°C using the combustion heat generated by burning fuel in the transfer pipe 200, and the molten copper or copper alloy discharged from the melting furnace 100 is transferred to the pure pot 300 while maintaining it in a molten state.

[0060] For example, the transfer pipe 200 can include an upper slag vessel 210 that removes impurities generated during the melting of the copper or copper alloy material or slag of the solid deoxidizer, a heat-insulating furnace 220 that functions as a buffer to compensate for the difference between the production rate and the melting rate of the ingot while maintaining the temperature of the molten copper or copper alloy, and a lower slag vessel 230 that removes impurities floating on the molten copper or copper alloy.

[0061] Figure 3 is an enlarged view showing the shape of the upper slag vessel.

[0062] In particular, the upper slag vessel 210 is provided with a discharge port 211 that is open at a portion connected to the holding furnace 220 so that the molten copper or copper alloy can be transferred to the holding furnace 220. Above the discharge port 211, a partition wall 212 may be provided to block the transfer of the solid deoxidizer to the holding furnace 220 so that the solid deoxidizer floating on the upper part of the molten copper or copper alloy does not move to the holding furnace 220. On the other hand, instead of providing the partition wall 212, it is also possible to form the width of the shape of the discharge port 211 longer than the height. In this way, it is important to prevent the solid deoxidizer from moving to the holding furnace 220 because if the solid deoxidizer is transferred after the holding furnace 220, it may induce a backflow in the transfer path of the molten copper or copper alloy. Here, the upper surface of the discharge port 211 may be on the same line as or lower than the lower surface of the opening part 213 described later.

[0063] Here, the reason for providing the opening part 213 as described above in front of the upper slag vessel 210 is that the gas generated during the production of the molten copper or copper alloy is discharged through the opening part 213, and a part of the solid deoxidizer can be discharged. Thus, it is possible to suppress the backflow of the molten copper or copper alloy in the upper slag vessel 210.

[0064] In particular, the solid deoxidizer floating on the upper part of the molten copper or copper alloy is stacked in the opening part 213, and together with the positive pressure of the internal gas of the upper slag vessel 210, it can prevent air from penetrating into the inside of the upper slag vessel 210 from the outside.

[0065] Also, by adjusting the concentration of carbon monoxide (CO) to more than 1.5% by volume and not more than 4.0% by volume through incomplete combustion of fuel at one or more positions selected from the group consisting of the upper slag vessel 210, the holding furnace 220, and the lower slag vessel 230, an additional deoxidation reaction by carbon monoxide (CO), which is a reducing gas, can be induced, and the oxygen concentration of the ingot can be further limited.

[0066] Furthermore, one or more selected from the group consisting of the upper slag vessel 210, the holding furnace 220, and the lower slag vessel 230, preferably, the lower slag vessel 230 may further be provided with a bubbler 231 for injecting an inert gas into the molten copper or copper alloy, as shown in FIG. 4. Further, the bubbler 231 is provided in a direction perpendicular to the ground on the upper surface of the lower slag vessel 230, whereby the structural stability and workability of the lower slag vessel 230 can be improved.

[0067] By injecting an inert gas such as argon (Ar) or nitrogen (N 2 ) into the molten copper or copper alloy through the bubbler 231, hydrogen (H 2 ) remaining in the molten copper or copper alloy can be discharged. When the concentration of the remaining hydrogen (H 2 ) is high, there is a problem that holes, cracks, etc. may occur in the ingot, or surface defects may be induced during rolling. Therefore, since the concentration of oxygen (O 2 ) and the concentration of hydrogen (H 2 ) in the molten copper or copper alloy are in an inverse proportional relationship, the concentration of oxygen (O 2 ) is maintained at the lowest level through a deoxidation reaction, and the concentration of hydrogen (H 2 ) is maintained at the highest level. It is preferable to inject an inert gas in the lower slag vessel 230 to reduce the concentration of the remaining hydrogen (H 2 ).

[0068] On the other hand, the step of discharging the molten copper or copper alloy transferred through the puapot 300 to the casting machine 400 is to inject the molten copper or copper alloy transferred through the transfer pipe 200 into the casting machine 400. The puapot 300, like the transfer pipe 200, uses the combustion heat generated by burning fuel to maintain the molten copper or copper alloy in a molten state and inject it into the casting machine 400.

[0069] Here, after being discharged from the discharge port of the poor pot 300 and before being poured into the casting machine 400, the molten copper or copper alloy may be contaminated with oxygen or other impurities by being exposed to external air. Therefore, as shown in FIG. 5, a spout torch 320 for applying a flame to the periphery of the molten copper or copper alloy to seal the molten copper or copper alloy poured into the casting machine 400 from the outside air may be further provided at the discharge port of the poor pot 300.

[0070] In addition, at the discharge port of the poor pot 300, since the discharged molten copper or copper alloy may adhere to and solidify on the external surface while scattering, a spout burner 330 for applying a flame to the surface of the discharge port to remelt and remove the adhered molten copper or copper alloy may be further provided. Further, the direction of the flame applied from the spout burner 330 may be provided such that, while being perpendicular to the direction of the flame applied from the spout torch 320, the respective flames do not directly interfere with each other.

[0071] In the step of manufacturing a copper or copper alloy ingot with the casting machine 400, the casting machine 400 may include a moving mold casting machine including a rotating casting wheel 410 and a belt 420 provided at a certain distance from the surface of the casting wheel. The molten copper or copper alloy discharged from the poor pot 300 is formed into an ingot by being cooled and solidified while being poured into the space provided between the casting wheel 410 and the belt 420. The formed ingot is transferred to a rolling mill 500 while being maintained at a temperature of 900 °C or higher and may be manufactured in the form of a wire by continuous rolling.

[0072] On the one hand, in one embodiment of the present invention, a casting method using a belt & wheel type moving mold casting machine composed of a belt 420 and a wheel 410 shown in FIG. 1 is mentioned. However, the present invention is not limited to such a casting method, and various casting methods can be used, such as a casting method using a so-called double belt type moving mold casting machine composed of two belts (see Japanese Registered Patent Publication No. 5137642), and a casting method using a continuous casting machine (see U.S. Registered Patent Publication No. 5037471).

[0073] Accordingly, the method and apparatus for manufacturing oxygen-free copper or an oxygen-free copper alloy according to the present invention can suppress the generation of holes, cracks, etc. in the ingot through a sufficient and uniform deoxidation reaction by applying a solid deoxidant in the melting furnace 100 instead of the transfer pipe 200 or the pu pot 300, and can produce high-quality oxygen-free copper or an oxygen-free copper alloy with good surface quality during rolling, showing an excellent effect.

[0074] In addition, the method and apparatus for manufacturing oxygen-free copper or an oxygen-free copper alloy according to the present invention do not perform a deoxidation reaction with a reducing gas in the melting furnace 100, so it is possible to prevent an increase in fuel cost and manufacturing cost due to incomplete combustion, and at the same time, it shows an excellent effect of suppressing damage to the interior materials of the melting furnace by the reducing gas.

Example

[0075] 1. Evaluation of backflow and oxygen concentration according to the input amount of solid deoxidant As described in Table 1 below, while varying the input amount of the solid deoxidant input into the melting furnace, the presence or absence of backflow of the copper melt in the transfer pipe and the oxygen concentration of the produced oxygen-free copper were evaluated.

[0076]

Table 1

[0077] As described in Table 1 above, when the input amount of the solid deoxidizer is less than 1 kg / ton, the oxygen concentration of the ingot increases and oxygen-free copper cannot be produced. On the other hand, when the input amount of the solid deoxidizer exceeds 6 kg / ton, it was confirmed that while an excessive amount of the solid deoxidizer is transferred to the transfer pipe together with the molten copper, at least partially blocks the passage, and induces backflow of the molten copper.

[0078] On the other hand, in the cases of Examples 1 to 6 where the input amount of the solid deoxidizer is 1 kg / ton or more and 6 kg / ton or less, the oxygen concentration can be maintained at 10 ppm or less, satisfying the conditions for oxygen-free copper wire. Since the input amount is appropriately adjusted, high-quality oxygen-free copper wire can be stably produced without backflow of the molten copper.

[0079] 2. Evaluation of Backflow due to Particle Size of Solid Deoxidizer and Failure of Dust Collector Filter As described in Table 2 below, while varying the average particle size of the solid deoxidizer charged into the melting furnace, the presence or absence of backflow of the molten copper in the transfer pipe, particularly in the upper slag vessel, and the presence or absence of failure of the dust collector filter provided at the upper part of the melting furnace were evaluated.

[0080]

Table 2

[0081] As described in Table 2 above, when the average particle size of graphite as the solid deoxidizer exceeds 30 mm, backflow is observed in the upper slag vessel. Further, when the average particle size of graphite is 1 mm or less, the solid deoxidizer is sucked into the dust collector, which may induce failure of the dust collector filter.

[0082] This specification has been described with reference to preferred embodiments of the present invention. However, those skilled in the art can variously modify and implement the present invention without departing from the spirit and scope of the present invention described in the claims set forth below. Therefore, if the modified implementations basically include the components of the claims of the present invention, they should all be regarded as being included in the technical scope of the present invention.

Claims

1. A method for manufacturing oxygen-free copper or an oxygen-free copper alloy, comprising: feeding copper or a copper alloy material and a solid deoxidizer into a melting furnace, and melting and deoxidizing the copper or copper alloy material; transferring the deoxidized copper or copper alloy molten metal through a transfer pipe; discharging the copper or copper alloy molten metal transferred through a pu pot into a casting machine; and manufacturing the copper or copper alloy molten metal into an ingot by the casting machine.

2. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to claim 1, wherein the solid deoxidizer contains one or more selected from the group consisting of graphite, charcoal, activated carbon, and coke.

3. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to claim 2, wherein the input amount of the solid deoxidizer is 1 kg / ton or more and 6 kg / ton or less based on the input amount of the copper or copper alloy material.

4. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to claim 2, wherein the size of the solid deoxidizer is 0.5 mm or more and 30 mm or less.

5. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to any one of claims 1 to 4, wherein a dust collector is further provided above the melting furnace.

6. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to any one of claims 1 to 4, wherein the concentration of carbon monoxide (CO) inside the melting furnace is adjusted to 3.5% by volume or less.

7. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to any one of claims 1 to 4, wherein the residence time of the solid deoxidizer inside the melting furnace is 5 minutes to 2 hours.

8. The method for manufacturing oxygen-free copper or an oxygen-free copper alloy according to any one of claims 1 to 4, wherein a spout torch for applying a flame to seal the copper or copper alloy molten metal discharged into the casting machine from the outside and a spout burner for applying a flame to remelt and remove the copper or copper alloy molten metal adhering to the outer surface of the discharge part are provided at the discharge port of the pu pot.

9. The transfer pipe includes an upper slag vessel that removes impurities generated during the melting of the copper or copper alloy material or the slag of the solid deoxidizer, a holding furnace that functions as a buffer to compensate for the difference between the production rate and the melting rate of the ingot while maintaining the temperature of the copper or copper alloy molten metal, and a lower slag vessel that removes impurities floating on the copper or copper alloy molten metal. The method for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 1 to 4 is characterized by including the above.

10. The method for producing oxygen-free copper or oxygen-free copper alloy according to claim 9, wherein the upper slag vessel has a width of the shape of the discharge port connected to the holding furnace that is longer than the height, or a partition wall is provided above the discharge port.

11. The method for producing oxygen-free copper or oxygen-free copper alloy according to claim 9, wherein the concentration of carbon monoxide is adjusted to more than 2.5% by volume and not more than 4.0% by volume at one or more positions selected from the group consisting of the holding furnace, the lower slag vessel, and the pu pot.

12. The method for producing oxygen-free copper or oxygen-free copper alloy according to claim 9, wherein the lower slag vessel is provided with a bubbler for injecting an inert gas into the copper or copper alloy molten metal.

13. The method for producing oxygen-free copper or oxygen-free copper alloy according to claim 12, wherein the inert gas includes argon gas or nitrogen gas.

14. The casting machine includes a moving mold casting machine including a rotating casting wheel and a belt provided at a certain interval from the surface of the casting wheel. The method for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 1 to 4 further includes a step of continuously rolling the ingot produced by the casting machine through a rolling mill.

15. An oxygen-free copper or oxygen-free copper alloy produced by the method for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 1 to 4.

16. The oxygen-free copper or oxygen-free copper alloy according to claim 15, wherein the alloy is in the form of a rod, a slab, or an ingot.

17. An apparatus for producing oxygen-free copper or oxygen-free copper alloy, comprising: A melting furnace for melting a copper or copper alloy material; A transfer pipe for transferring the copper or copper alloy molten metal melted in the melting furnace; A pu pot for discharging the copper or copper alloy molten metal transferred through the transfer pipe; and A casting machine for producing an ingot while cooling the molten copper or copper alloy discharged from the pu pot; An apparatus for producing oxygen-free copper or oxygen-free copper alloy, in which a solid deoxidizer is charged into the melting furnace together with the copper or copper alloy material.

18. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to claim 17, wherein the solid deoxidizer contains one or more selected from the group consisting of graphite, charcoal, activated carbon, and coke.

19. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to claim 18, wherein the charging amount of the solid deoxidizer is 1 kg / ton or more and 6 kg / ton or less based on the charging amount of the copper or copper alloy material.

20. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to claim 18, wherein the size of the solid deoxidizer is 1 mm or more and 30 mm or less.

21. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 17 to 20, wherein a dust collector is further provided above the melting furnace.

22. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 17 to 20, wherein the concentration of carbon monoxide (CO) inside the melting furnace is adjusted to 3.5% by volume or less.

23. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 17 to 20, wherein the residence time of the solid deoxidizer inside the melting furnace is 5 minutes to 2 hours.

24. The apparatus for producing oxygen-free copper or oxygen-free copper alloy according to any one of claims 17 to 20, wherein a spout torch for applying a flame to seal the molten copper or copper alloy discharged from the pu pot to the casting machine from the outside, and a spout burner for applying a flame to remelt and remove the molten copper or copper alloy fixed to the outer surface of the discharge part are provided.

25. The transfer pipe includes an upper slag vessel that removes impurities generated during the melting of the copper or copper alloy material or slag of the solid deoxidizer, a holding furnace that functions as a buffer for compensating for the difference between the production rate and the melting rate of the ingot while maintaining the temperature of the copper or copper alloy molten metal, and a lower slag vessel that removes impurities floating on the copper or copper alloy molten metal. The apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to any one of claims 17 to 20 is characterized by including these components.

26. The upper slag vessel is characterized in that the width of the shape of the discharge port connected to the holding furnace is longer than the height, or a partition wall is provided above the discharge port. The apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to claim 25 is characterized by this.

27. The concentration of carbon monoxide is adjusted to more than 2.5% by volume and 4.0% by volume or less at one or more positions selected from the group consisting of the holding furnace, the lower slag vessel, and the puapot. The apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to claim 25 is characterized by this.

28. The lower slag vessel is provided with a bubbler for injecting an inert gas into the copper or copper alloy molten metal. The apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to claim 25 is characterized by this.

29. The inert gas includes argon gas or nitrogen gas. The apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to claim 25 is characterized by this.

30. The casting machine includes a moving mold casting machine including a rotating casting wheel and a belt provided at a certain distance from the surface of the casting wheel. The apparatus for manufacturing oxygen-free copper or oxygen-free copper alloy according to any one of claims 17 to 20 further includes a rolling mill for continuously rolling the ingot produced by the casting machine.

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