JP2006153362A - Metal melting and tapping device, and its casting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal melting and tapping device and a casting device using the same capable of repeatedly and smoothly melting and tapping metal without contaminating molten metal. <P>SOLUTION: This metal melting and tapping device comprises a levitation melting furnace 11, and a tapping nozzle 21 constituted similarly as the levitation melting furnace and connected with a hearth part of the levitation melting furnace, and the tapping nozzle comprises a nozzle main body having an inverted circular conical portion and a nozzle portion 26 connected with the inverted circular conical portion and having the approximately funnel-shape as a whole, and a coil 24 mounted around an outer periphery of the nozzle main body. The metal is floated and melted in the levitation melting furnace, and the molten metal is tapped from the tapping nozzle. The coil around the outer periphery of the nozzle main body is projected downward with respect to a lower end of a nozzle portion of the nozzle main body. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal melting and pouring apparatus and a casting apparatus using the same, and more specifically, a levitation melting furnace and a tapping nozzle connected to the hearth of the furnace, and floating and melting the metal in the levitation melting furnace. Next, the present invention relates to a metal melting and pouring apparatus in which the molten metal is discharged from the pouring nozzle and a metal casting apparatus in which the molten metal thus discharged is further solidified by a mold.

  Conventionally, as the above-described metal melting and hot water supply apparatus, a levitation melting furnace (also referred to as a cold crucible melting furnace) is configured in the same manner as the levitation melting furnace and connected to the hearth of the levitation melting furnace. The thing provided with the hot water nozzle is known (for example, refer patent document 1 and 2). In this conventional apparatus, the levitation melting furnace includes a furnace body composed of a plurality of water-cooled copper segments that are insulated from each other and arranged in a cylindrical shape, and a coil disposed around the outer periphery of the furnace body. The hot water nozzle includes a nozzle body configured in the same manner as the furnace body of the levitation melting furnace, and a coil disposed around the outer periphery of the nozzle body. The nozzle body is formed in a substantially funnel shape as a whole having an inverted conical portion and a nozzle portion connected thereto.

  In the above-described conventional apparatus, first, the metal charged into the furnace body is induction-heated by flowing a high-frequency current through a coil disposed around the outer periphery of the furnace body, and is levitated and melted by the Lorentz repulsive force generated at this time. At this stage, the molten metal is floated in the furnace body, but a solidified shell is formed on the hearth of the furnace body and the inverted conical part of the nozzle body connected thereto. Next, the solidified shell formed on the inverted conical portion of the nozzle body is melted by inductively heating the coil disposed around the outer periphery of the nozzle body by flowing high frequency current, and the molten metal in the furnace body is melted into the nozzle. The hot water comes out of the main body.

However, in the above-mentioned conventional apparatus, at the end of the molten metal discharge, particularly at the end, the solidified product of the molten metal is generated at the nozzle portion of the nozzle body, particularly at the lower portion of the nozzle portion, and hangs down in an icicle shape. There is a problem of blocking the part. In the conventional apparatus, since the coil is disposed only around the outer periphery of the nozzle body, the magnetic field formed by flowing a high-frequency current through the coil is generated at the lower part of the inverted conical part that forms the central part of the nozzle body or the nozzle. Strong in the upper part of the nozzle, but weak in the upper part of the inverted conical part that forms both ends of the nozzle body and in the lower part of the nozzle part, and in the nozzle part, a plurality of water-cooled copper segments forming the nozzle body are close to each other Therefore, the molten metal tends to solidify from the bottom of the nozzle portion. In the initial and middle stages of the molten metal, the hot molten metal is sufficiently replenished in sequence, so the molten metal in the molten metal does not solidify even at the bottom of the nozzle, but at the end of the molten metal, especially at the end, Since there is little or almost no replenishment of the molten metal, the molten metal in the tapping is solidified at the lower part of the nozzle part, and the nozzle part is blocked as described above. If the nozzle part of the nozzle body is blocked by the solidified product of the molten metal, the next molten metal outflow cannot be performed as it is. In order to prevent the nozzle part of the nozzle body from being clogged with molten solidified material, a heat insulating layer, a heat insulating layer, etc. are provided on the inner surface of the nozzle body including the nozzle part to make it difficult for the molten metal solidified material to be generated. Although it thinks, if it does in this way, it will be inevitable that a molten metal will be contaminated by such a heat insulation layer or a heat generation heat insulation layer.
JP 2000-274951 A JP 2001-41661 A

  The problem to be solved by the present invention is to provide a metal melted hot water apparatus that can smoothly and repeatedly perform metal melted hot water without causing contamination of the molten metal, and such metal melted hot water apparatus. It is in the place which provides the metal casting apparatus using this.

  The present invention for solving the above-mentioned problems includes a levitation melting furnace, and a tapping nozzle configured in the same manner as the levitation melting furnace and connected to the hearth of the levitation melting furnace. The nozzle includes a nozzle body formed in a substantially funnel shape as a whole having an inverted conical portion and a nozzle portion connected to the inverted cone portion, and a coil disposed around the outer periphery of the nozzle body, and the metal is added to the levitation melting furnace. In the metal melting and pouring device in which the molten metal is levitated and melted and then discharged from the pouring nozzle, the coil disposed around the outer periphery of the nozzle body projects downward from the lower end of the nozzle portion of the nozzle body. The present invention relates to a metal melting and pouring device characterized in that it is arranged.

  Further, the present invention includes the above-described metal melting and pouring device according to the present invention and a mold connected to the melting and pouring device, so that the molten metal discharged from the pouring nozzle of the melting and pouring device is solidified by the mold. An apparatus for casting a metal, wherein the upper part of the mold is configured in the same manner as the levitation melting furnace of the molten hot water apparatus, and a hot water is formed on the upper part. Concerning.

  First, the metal melted hot water apparatus according to the present invention will be described. The metal melting and pouring apparatus according to the present invention also includes a levitation melting furnace and a hot water nozzle configured in the same manner as the levitation melting furnace and connected to the hearth of the levitation melting furnace. The levitation melting furnace includes a furnace body composed of a plurality of water-cooled copper segments that are insulated from each other and arranged in a cylindrical shape, and a coil that is disposed around the outer periphery of the furnace body. The nozzle main body comprised similarly to the furnace main body of this levitation melting furnace, and the coil arrange | positioned around the outer periphery of this nozzle main body is provided. The nozzle body is formed in a substantially funnel shape as a whole having an inverted conical portion and a nozzle portion connected thereto.

  In the metal melted hot water apparatus according to the present invention, the coil disposed around the outer periphery of the nozzle body is disposed so as to protrude downward from the lower end of the nozzle portion of the nozzle body. The coil disposed around the outer periphery of the nozzle body is disposed not only around the outer periphery of the nozzle body but also projects downward from the lower end of the nozzle portion of the nozzle body. The degree of protrusion is preferably 20% or more of the inner diameter of the coil at the lower part of the nozzle part, and more preferably 20 to 50%.

  In the metal melted hot water apparatus according to the present invention, as in the conventional apparatus, first, the metal charged into the furnace body is induction-heated by flowing a high-frequency current through a coil arranged around the outer periphery of the furnace body. Levitates and dissolves due to Lorentz repulsive force At this stage, the molten metal is floated in the furnace body, but a solidified shell is formed on the hearth of the furnace body and the inverted conical part of the nozzle body connected thereto. Next, the solidified shell formed on the inverted conical portion of the nozzle body is melted by inductively heating the coil disposed around the outer periphery of the nozzle body by flowing high frequency current, and the molten metal in the furnace body is melted into the nozzle. The hot water comes out of the main body.

  In the metal melted hot water apparatus according to the present invention, the coil is arranged not only around the outer periphery of the nozzle body but also downward from the lower end of the nozzle portion of the nozzle body, so that a high-frequency current flows through the coil. The magnetic field formed by is not only lower at the lower part of the inverted conical part and the upper part of the nozzle part forming the nozzle body but also at the lower part of the nozzle part. In the nozzle part of the nozzle body, a plurality of water-cooled copper segments forming the nozzle body are close to each other, and at the lower part of the nozzle part, is there a small amount of replenishment of high temperature molten metal at the end of the molten metal discharge, especially at the end? Or, since there is almost no melting of the molten metal in the tapping water, the lower portion of the nozzle portion is likely to be blocked due to such solidification. Can be induction-heated to a correspondingly high temperature, so that the lower part of the nozzle part, and thus the nozzle part, can be prevented from being blocked by the solidified material of the molten metal.

  In the molten metal tapping apparatus according to the present invention, the solidification of the molten metal in the lower part of the nozzle part of the nozzle body and the clogging of the nozzle part due to this can be prevented more reliably. For this purpose, it is preferable that the minimum inner diameter of the nozzle portion of the nozzle body is formed to be correspondingly wide. The minimum inner diameter of the nozzle part is preferably formed to be at least twice the minimum thickness of the solidified shell formed on the hearth part of the furnace body, and more preferably 2 to 5 times. .

  Next, the metal casting apparatus according to the present invention will be described. A metal casting apparatus according to the present invention includes the above-described metal melting and pouring apparatus according to the present invention and a mold connected to the melting and pouring apparatus, and the upper part of the mold is levitation melting of the melting and pouring apparatus. The structure is the same as that of the furnace, and when the molten metal discharged from the hot water discharge nozzle of the molten hot water apparatus is solidified by the mold, the hot water is formed at the upper part of the mold. The upper part of the mold is like the levitation melting furnace of the melting and hot water supply apparatus, and a mold frame made up of a plurality of water-cooled copper segments that are insulated from each other and arranged in a cylindrical shape, and a coil disposed around the outer periphery of the mold frame It is equipped with. The upper part of such a mold can be directly connected to the molten hot water apparatus, but the molten hot water apparatus is connected to the molten hot water apparatus via a connecting frame that can maintain the inside of the mold in, for example, an argon gas atmosphere. It can also be connected to the hearth of the smelting furnace.

  When the molten metal discharged from the hot water discharge nozzle of the molten hot water apparatus is solidified with the mold, if the solid is simply solidified as it is, the resulting casting will have a large shrinkage in the center. When induction heating is performed by flowing a high-frequency current to a coil arranged around the outer periphery of the frame, a hot water is formed here, and a casting having no shrinkage can be obtained by the hot water.

  According to the metal melting and pouring apparatus according to the present invention, the metal melting and pouring hot water can be repeatedly and smoothly performed without causing contamination of the molten metal, and the metal casting apparatus according to the present invention can further reduce shrinkage. No desired casting can be obtained.

  FIG. 1 is a longitudinal cross-sectional view illustrating a metal melted hot water apparatus according to the present invention. 1 includes a levitation melting furnace 11 and a hot water nozzle 21 that is configured in the same manner as the levitation melting furnace 11 and connected to the hearth 12 of the levitation melting furnace 11. ing. The levitation melting furnace 11 includes a furnace body 14 composed of a plurality of water-cooled copper segments 13, 13... That are insulated from each other and arranged in a cylindrical shape, and a coil 15 disposed around the outer periphery of the furnace body 14. I have. Further, the hot water nozzle 21 includes a nozzle body 23 composed of a plurality of water-cooled copper segments 22, 22... That are insulated from each other and arranged radially upward, and a coil 24 that is disposed around the outer periphery of the nozzle body 23. ing.

  The nozzle body 23 is formed in a substantially funnel shape as a whole comprising an upper inverted cone portion 25 and a lower nozzle portion 26 connected to the upper inverted cone portion 25, and the inverted cone portion 25 is connected to the hearth 12 of the furnace body 14. Has been. The coil 24 is disposed not only around the outer periphery of the nozzle body 23, that is, around the outer periphery of the inverted conical portion 25 and the nozzle portion 26, but also protrudes downward from the lower end of the nozzle portion 26. In the case of the metal melted hot water apparatus illustrated in FIG. 1, the degree of protrusion of the coil 24, that is, the protrusion width H is 30% of the inner diameter D of the coil 24 at the lower portion of the nozzle portion 26. 1, the minimum inner diameter d of the nozzle portion 26 is twice the minimum thickness h of the solidified shell B formed on the hearth portion 12.

  FIG. 1 shows a state in which the metal charged into the furnace body 14 is induction-heated by flowing a high-frequency current through the coil 15 and is floated and melted by the Lorentz repulsive force generated at this time. At this stage, the molten metal A is floated in the furnace body 14, and the solidified shell B is formed on the hearth 12 including the lower end of the furnace body 14 and the inverted conical part 25 of the nozzle body 23. ing. When the molten metal A is discharged, a portion of the solidified shell B formed on the inverted conical portion 25 of the nozzle body 23 is melted by induction heating by flowing a high-frequency current through the coil 24, and the inside of the furnace body 14 is melted. And the inside of the nozzle part 26 are communicated. Thus, the molten metal A in the furnace body 14 is discharged from the nozzle portion 26 of the nozzle body 23.

  As described above, the coil 24 is disposed not only around the outer periphery of the nozzle body 23 but also below the lower end of the nozzle portion 26, and by passing a high-frequency current through the coil 24, the lower portion of the nozzle portion 26 is disposed. Therefore, the molten metal in the middle of the molten metal can be induction-heated to a corresponding high temperature at the lower portion of the nozzle portion 26, so that the molten metal solidifies at the lower portion of the nozzle portion 26 and closes the nozzle portion 26. Can be prevented.

  FIG. 2 is a longitudinal sectional view illustrating a metal casting apparatus according to the present invention. The metal casting apparatus illustrated in FIG. 2 includes the metal melting and pouring apparatus according to the present invention described above with reference to FIG. 1 and a mold 31 connected to the melting and pouring apparatus. The casting mold 31 is formed by an upper part 32 and a lower part 33 connected to the upper part 32, and the upper part 32 is connected to the hearth 12 of the levitation melting furnace 11 constituting the melting hot water apparatus through a connecting frame 34. . The upper part 32 of the casting mold 31 is configured in the same manner as the levitation melting furnace 11, and a casting mold frame 36 comprising a plurality of water-cooled copper segments 35, 35,. And a coil 37 disposed around the outer periphery of 36, and the lower portion 33 is an ingot case.

  As described above, when the metal is levitated and melted in the furnace main body 14 of the levitation melting furnace 11 and the molten metal A is discharged from the nozzle portion 26 of the hot water nozzle 21, the molten metal flows down into the mold 31 sequentially by its own weight. And then solidify. Such solidification is fast at the wall surface portion of the mold 31 and slow at the central portion, and if left as it is, it becomes a casting having a large shrinkage cavity in the central portion. In the metal casting apparatus according to the present invention illustrated in FIG. 2, by passing a high-frequency current to the coil 37 from the last stage to the end of the above-described hot water, the molten metal and a part thereof surrounded by the mold frame 36 are The solidified product is heated by induction heating and melted by floating, and the melted and melted is made to act as a hot water. 3 and 4 are longitudinal sectional views showing the operating state of the metal casting apparatus according to the present invention illustrated in FIG. Among these, FIG. 3 shows a state in which a high-frequency current flows through the coil 37 from the end to the end of the hot water as described above, and FIG. 4 stops the high-frequency current from flowing through the coil 37 thereafter. Indicates the state. 3 and 4, C indicates a solidified substance, and D indicates a molten metal that is levitated and melted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view illustrating a metal melted hot water apparatus according to the present invention. The longitudinal cross-sectional view which illustrates the casting apparatus of the metal which concerns on this invention. The longitudinal cross-sectional view which shows the action state of the casting apparatus of FIG. The longitudinal cross-sectional view which shows the other action state of the casting apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Levitation melting furnace 12 Hearth part 13,22,35 Water-cooled copper segment 14 Furnace main body 15,24,37 Coil 21 Hot water nozzle 23 Nozzle main body 25 Reverse cone part 26 Nozzle part 31 Mold 32 Upper part 33 Lower part 34 Connection frame 36 Mold Frame A, D Molten metal B Solidified shell C Solidified material

Claims (3)

  A levitation melting furnace, and a hot water nozzle configured in the same manner as the levitation melting furnace and connected to a hearth of the levitation melting furnace, the hot water nozzle being an inverted conical portion and a nozzle connected thereto And a coil body disposed around the outer periphery of the nozzle body, the metal is levitated and melted in the levitation melting furnace, and then the molten metal is In the metal melting and pouring apparatus for discharging hot water from the hot water nozzle, the coil disposed around the outer periphery of the nozzle body is disposed so as to protrude downward from the lower end of the nozzle portion of the nozzle body. Metal melting and tapping equipment.   The metal melted hot water apparatus according to claim 1, wherein the minimum inner diameter of the nozzle portion of the nozzle body is formed to be at least twice the minimum thickness of the solidified shell formed on the hearth portion. A metal casting comprising the metal melted hot water apparatus according to claim 1 and a mold connected to the melted hot water apparatus, and the molten metal discharged from the hot water nozzle of the melted hot water apparatus is solidified by the mold. An apparatus for casting a metal, characterized in that the upper part of the mold is configured in the same manner as the levitation melting furnace of the molten hot water apparatus, and the hot water is formed on the upper part.

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